Posterior open wound healing in immediate implant placement using reactive soft tissue versus absorbable collagen sponge: a retrospective cohort study

The soft and hard tissue healing of open wounds in immediate implant placement are yet to be explored. The aim of this study was to compare the clinical outcomes of open wound healing using reactive soft tissue (RST) and absorbable collagen sponge (ACS). Forty implants placed immediately in posterior sockets were included; autologous RST was used in 20 and ACS substitute was used in 20. Soft tissue healing was primarily assessed through a novel scoring system and the evaluation of gingival recession. The horizontal bone width (HBW) and interproximal marginal bone level (MBL) were measured on radiographs to observe the hard tissue healing. No significant difference in total soft tissue healing score was observed at 2 weeks postoperatively. Notably, the ACS group showed better tissue colour (P = 0.016) but worse fibrous repair (P = 0.043) scores than the RST group. Gingival recession levels were comparable in the two groups, both before tooth extraction and after placement of the restoration. Regarding hard tissue, HBW and MBL changes showed no intergroup differences. Within the limitations of this study, both RST and ACS seemed effective for open wound closure, achieving ideal soft and hard tissue healing in immediate implant placement.

Combined brain topological metrics with machine learning to distinguish essential tremor and tremor-dominant Parkinson's disease

BACKGROUND

Essential tremor (ET) and Parkinson's disease (PD) are the two most prevalent movement disorders, sharing several overlapping tremor clinical features. Although growing evidence pointed out that changes in similar brain network nodes are associated with these two diseases, the brain network topological properties are still not very clear.

OBJECTIVE

The combination of graph theory analysis with machine learning (ML) algorithms provides a promising way to reveal the topological pathogenesis in ET and tremor-dominant PD (tPD).

METHODS

Topological metrics were extracted from Resting-state functional images of 86 ET patients, 86 tPD patients, and 86 age- and sex-matched healthy controls (HCs). Three steps were conducted to feature dimensionality reduction and four frequently used classifiers were adopted to discriminate ET, tPD, and HCs.

RESULTS

A support vector machine classifier achieved the best classification performance of four classifiers for discriminating ET, tPD, and HCs with 89.0% mean accuracy (mACC) and was used for binary classification. Particularly, the binary classification performances among ET vs. tPD, ET vs. HCs, and tPD vs. HCs were with 94.2% mACC, 86.0% mACC, and 86.3% mACC, respectively. The most power discriminative features were mainly located in the default, frontal-parietal, cingulo-opercular, sensorimotor, and cerebellum networks. Correlation analysis results showed that 2 topological features negatively and 1 positively correlated with clinical characteristics.

CONCLUSIONS

These results demonstrated that combining topological metrics with ML algorithms could not only achieve high classification accuracy for discrimination ET, tPD, and HCs but also help to reveal the potential brain topological network pathogenesis in ET and tPD.

Using histogram analysis of the intrinsic brain activity mapping to identify essential tremor

Background

Essential tremor (ET) is one of the most common movement disorders. Histogram analysis based on brain intrinsic activity imaging is a promising way to identify ET patients from healthy controls (HCs) and further explore the spontaneous brain activity change mechanisms and build the potential diagnostic biomarker in ET patients.

Methods

The histogram features based on the Resting-state functional magnetic resonance imaging (Rs-fMRI) data were extracted from 133 ET patients and 135 well-matched HCs as the input features. Then, a two-sample t-test, the mutual information, and the least absolute shrinkage and selection operator methods were applied to reduce the feature dimensionality. Support vector machine (SVM), logistic regression (LR), random forest (RF), and k-nearest neighbor (KNN) were used to differentiate ET and HCs, and classification performance of the established models was evaluated by the mean area under the curve (AUC). Moreover, correlation analysis was carried out between the selected histogram features and clinical tremor characteristics.

Results

Each classifier achieved a good classification performance in training and testing sets. The mean accuracy and area under the curve (AUC) of SVM, LR, RF, and KNN in the testing set were 92.62%, 0.948; 92.01%, 0.942; 93.88%, 0.941; and 92.27%, 0.939, respectively. The most power-discriminative features were mainly located in the cerebello-thalamo-motor and non-motor cortical pathways. Correlation analysis showed that there were two histogram features negatively and one positively correlated with tremor severity.

Conclusion

Our findings demonstrated that the histogram analysis of the amplitude of low-frequency fluctuation (ALFF) images with multiple machine learning algorithms could identify ET patients from HCs and help to understand the spontaneous brain activity pathogenesis mechanisms in ET patients.

Identification of essential tremor based on resting-state functional connectivity

Currently, machine-learning algorithms have been considered the most promising approach to reach a clinical diagnosis at the individual level. This study aimed to investigate whether the whole-brain resting-state functional connectivity (RSFC) metrics combined with machine-learning algorithms could be used to identify essential tremor (ET) patients from healthy controls (HCs) and further revealed ET-related brain network pathogenesis to establish the potential diagnostic biomarkers. The RSFC metrics obtained from 127 ET patients and 120 HCs were used as input features, then the Mann-Whitney U test and the least absolute shrinkage and selection operator (LASSO) methods were applied to reduce feature dimensionality. Four machine-learning algorithms were adopted to identify ET from HCs. The accuracy, sensitivity, specificity and the area under the curve (AUC) were used to evaluate the classification performances. The support vector machine, gradient boosting decision tree, random forest and Gaussian naïve Bayes algorithms could achieve good classification performances with accuracy at 82.8%, 79.4%, 78.9% and 72.4%, respectively. The most discriminative features were primarily located in the cerebello-thalamo-motor and non-motor circuits. Correlation analysis showed that two RSFC features were positively correlated with tremor frequency and four RSFC features were negatively correlated with tremor severity. The present study demonstrated that combining the RSFC matrices with multiple machine-learning algorithms could not only achieve high classification accuracy for discriminating ET patients from HCs but also help us to reveal the potential brain network pathogenesis in ET.

Combined brain network topological metrics with machine learning algorithms to identify essential tremor

BACKGROUND AND OBJECTIVE

Essential tremor (ET) is a common movement syndrome, and the pathogenesis mechanisms, especially the brain network topological changes in ET are still unclear. The combination of graph theory (GT) analysis with machine learning (ML) algorithms provides a promising way to identify ET from healthy controls (HCs) at the individual level, and further help to reveal the topological pathogenesis in ET.

METHODS

Resting-state functional magnetic resonance imaging (fMRI) data were obtained from 101 ET and 105 HCs. The topological properties were analyzed by using GT analysis, and the topological metrics under every single threshold and the area under the curve (AUC) of all thresholds were used as features. Then a Mann-Whitney U-test and least absolute shrinkage and selection operator (LASSO) were conducted to feature dimensionality reduction. Four ML algorithms were adopted to identify ET from HCs. The mean accuracy, mean balanced accuracy, mean sensitivity, mean specificity, and mean AUC were used to evaluate the classification performance. In addition, correlation analysis was carried out between selected topological features and clinical tremor characteristics.

RESULTS

All classifiers achieved good classification performance. The mean accuracy of Support vector machine (SVM), logistic regression (LR), random forest (RF), and naïve bayes (NB) was 84.65, 85.03, 84.85, and 76.31%, respectively. LR classifier achieved the best classification performance with 85.03% mean accuracy, 83.97% sensitivity, and an AUC of 0.924. Correlation analysis results showed that 2 topological features negatively and 1 positively correlated with tremor severity.

CONCLUSION

These results demonstrated that combining topological metrics with ML algorithms could not only achieve high classification accuracy for discrimination ET from HCs but also help us to reveal the potential topological pathogenesis of ET.

Outcomes of a quality improvement project aimed at improving delivery of new anticancer drug education to nursing in an academic-community hybrid model

50

Background: Educating staff on new anticancer medications is imperative for patient safety. Infusion nurses at Dana Farber Cancer Institute (DFCI) satellite infusion centers were surveyed on their comfort level administering newer oncology drugs. Results revealed only 57% of nurses were “extremely comfortable or somewhat comfortable,” while 32% of nurses were “somewhat uncomfortable or very uncomfortable.” This project aimed to increase percentage of nurses at the satellites indicating they are “extremely comfortable” or “somewhat comfortable” from baseline of 57% to ≥75%. Methods: An interdisciplinary team including pharmacy, medical oncology, and nursing was formed to analyze workflows around new drug onboarding, staff education, and satellite communication. The team utilized Plan-Do-Study-Act (PDSA) cycle methodology. Tools included process maps and fishbone to identify areas of improvement. Intervention development tools included a Pareto chart and a priority matrix. Results were analyzed using statistical process control charts. Results: PDSA cycle 1 consisted of making the pharmacy driven education sheet, At-A-Glance (AAG), more accessible for new drugs. AAGs for drugs approved by the FDA in the previous 18 months were posted on the DFCI pharmacy intranet page. Nurses were educated on how to access AAG weekly. For PDSA cycle 2, the survey was modified to target individual nurses administering new drugs rather than all nurses. A “Nursing consideration” section was added to the AAG template and workflow developed; Navigation and review of AAG was added to nursing competency. Monthly nursing/pharmacy huddles were established to optimize communication. These interventions increased the percentage of nurses indicating they are “extremely comfortable” or “somewhat comfortable” to ≥75% which was sustainable through PDSA cycle 2 (see Table). Conclusions: Making an easy-to-use nursing education resource accessible improved nursing comfort level. There were challenges with nursing survey due to COVID-19 surge and staff shortages. Routine huddles are essential for sustainability.[Table: see text]

Evaluation of the use of COVID-19 vaccines in patients treated with immunotherapy

e18781

Background: Immunotherapy can boost a patient’s immune system to bring about anti-tumor activity and may theoretically exaggerate the inflammatory immune response to infection or vaccinations. Conversely, vaccination may enhance immune activity in patients on immunotherapy. Currently, there are limited safety data in patients treated with immunotherapy who received COVID-19 vaccines. Methods: An IRB-approved retrospective review of Dana-Farber Cancer Institute patients treated with PD-1 checkpoint inhibitors and received COVID-19 vaccines was performed. The primary endpoint was the incidence rate of immune-related adverse events (irAEs) pre- and post- COVID-19 vaccinations. An Electronic Health Record search identified all patients who completed COVID-19 vaccines between 12/1/2020 and 3/31/2021 and received anti-PD-1 monotherapy between 10/1/2020 and 5/31/2021. Medical record review identified timing, occurrence, and grading of irAEs as defined by clinicians or Common Terminology Criteria for Adverse Events (CTCAE), version 5.0. Results: A total of 229 patients were included in the study. The most common underlying cancers were lung (32%) and melanoma (26%). The majority of patients had Pfizer-BioNTech COVID-19 vaccine; 64% of all patients received the third dose of vaccine. The median duration of treatment was 15 months, and median duration of follow-up was 19 months. Among the study cohort, 120 irAEs occurred before vaccination (any grade); 30 (25%) were grade 1, 35 (29%) were grade 2, 11 (9%) were grade 3 or 4, and 44 (37%) were ungraded. The main types of irAEs were skin toxicities (37% of all irAEs) followed by thyroid dysfunction (22%) and colitis (11%). Of the 75 irAEs that occurred after vaccination, 24 (32%) were grade 1, 16 (21%) were grade 2, 16 (21%) were grade 3 or 4, and 19 (26%) were ungraded. The main irAEs types were skin toxicity (31% of all irAEs) followed by thyroid dysfunction (13%) and hepatic toxicity (12 %). The all-grade pre- and post-vaccine irAE incidence rates per 100 patient-months were 4.13 and 5.09, respectively. Within this cohort, there were 0.96 (95% CI -0.362-2.284, p = 0.15) more irAEs post vaccine per 100 patient-months of anti-PD-1 therapy. Conclusions: The data weakly suggested that there is a higher incidence of irAEs post COVID-19 vaccine; however, the comparison did not achieve statistical significance. Further analysis of other patient characteristics will help to determine if any specific patterns are observed.[Table: see text]

Combined Intrinsic Local Functional Connectivity With Multivariate Pattern Analysis to Identify Depressed Essential Tremor

Background

Although depression is one of the most common neuropsychiatric symptoms in essential tremor (ET), the diagnosis biomarker and intrinsic brain activity remain unclear. We aimed to combine multivariate pattern analysis (MVPA) with local brain functional connectivity to identify depressed ET.

Methods

Based on individual voxel-level local brain functional connectivity (regional homogeneity, ReHo) mapping from 41 depressed ET, 43 non-depressed ET, and 45 healthy controls (HCs), the binary support vector machine (BSVM) and multiclass Gaussian Process Classification (MGPC) algorithms were used to identify depressed ET patients from non-depressed ET and HCs, the accuracy and permutations test were used to assess the classification performance.

Results

The MGPC algorithm was able to classify the three groups (depressed ET, non-depressed ET, and HCs) with a total accuracy of 84.5%. The BSVM algorithm achieved a better classification performance with total accuracy of 90.7, 88.64, and 90.48% for depressed ET vs. HCs, non-depressed ET vs. HCs, and depressed ET vs. non-depressed ET, and the sensitivity for them at 80.49, 76.64, and 80.49%, respectively. The significant discriminative features of depressed ET vs. HCs were primarily located in the cerebellar-motor-prefrontal gyrus-anterior cingulate cortex pathway, and for depressed ET vs. non-depressed ET located in the cerebellar-prefrontal gyrus-anterior cingulate cortex circuits. The partial correlation showed that the ReHo values in the bilateral middle prefrontal gyrus (positive) and the bilateral cerebellum XI (negative) were significantly correlated with clinical depression severity.

Conclusion

Our findings suggested that combined individual ReHo maps with MVPA not only could be used to identify depressed ET but also help to reveal the intrinsic brain activity changes and further act as the potential diagnosis biomarker in depressed ET patients.

[Application of face scanning in implant-supported restoration treatment of dentition defect]

In recent years, the increasingly mature oral digital technology has opened a new era of implant treatment. Before implant treatment, digital information is collected from various aspects and virtual patients are constructed based on three-dimensional (3D) scanning technology, and this greatly optimizes the preoperative virtual tooth arrangement, esthetic design and implant treatment plan, and brings great clinical convenience to patients and doctors. In this review, the application and new progress of facial 3D scanning technology in the field of implantology will be described, and the opportunities and challenges brought by digitalization technology to clinicians will be deeply discussed, in order to provide a reference for implantologists to fully understand the application of digitalization in the field of implantology.

Blood Flow Velocimetry in a Microchannel During Coagulation Using Particle Image Velocimetry and Wavelet-Based Optical Flow Velocimetry

This article describes novel measurements of the velocity of whole blood flow in a microchannel during coagulation. The blood is imaged volumetrically using a simple optical setup involving a white light source and a microscope camera. The images are processed using particle image velocimetry (PIV) and wavelet-based optical flow velocimetry (wOFV), both of which use images of individual blood cells as flow tracers. Measurements of several clinically relevant parameters such as the clotting time, decay rate, and blockage ratio are computed. The high-resolution wOFV results yield highly detailed information regarding thrombus formation and corresponding flow evolution that is the first of its kind.

Incidence of hypertension and proteinuria in patients treated with bevacizumab versus bevacizumab biosimilar

83

Background: Biosimilar products are proven to have no clinically meaningful differences in terms of safety and effectiveness with the reference product, however, to our knowledge, there is limited comparative analysis regarding adverse events for the bevacizumab biosimilars and the reference product. The purpose of this study was to evaluate the incidence of hypertension and proteinuria in patients treated with reference versus biosimilar bevacizumab to potentially streamline clinical management. Methods: A retrospective study was conducted with data consisting of gastrointestinal cancer patients who initiated either reference bevacizumab or biosimilar bevacizumab between January 2019 and July 2020 at Roswell Park Comprehensive Cancer Center. For the primary composite endpoint, Electronic Health Records were searched for the presence or absence of hypertension and proteinuria, as well as time to event analysis. In patients treated with bevacizumab biosimilar, demographics, hypertension and proteinuria related risk factors, bevacizumab containing chemotherapy regimen, and bevacizumab dosing were also identified to assess the risk association with hypertension and proteinuria. Results: 75 patients were included with 42 patients received bevacizumab and 33 patients received bevacizumab biosimilar. Hypertension occurred in 52.4% of reference bevacizumab group versus 36.4% of bevacizumab biosimilar group. Median time to hypertension is 84 days (bevacizumab) versus 24.5 days (bevacizumab biosimilar) following the first treatment (p= 0.0064). Proteinuria developed in 35.7% of reference bevacizumab patients compared to 30% of bevacizumab biosimilar patients. Median onset of proteinuria was 213 days (bevacizumab) versus 53.5 days (bevacizumab biosimilar) (p= 0.0022). In patients with a history of hypertension or underlying renal dysfunction, there was an increased risk of further hypertension and proteinuria, respectively. Conclusions: Higher risk of hypertension and proteinuria was associated with the bevacizumab reference product group, although not statistically significant. A shorter onset of hypertension and proteinuria was associated with the bevacizumab biosimilar group. Our results need further validation in larger cohorts, especially due to the more recent implementation of bevacizumab biosimilar products. [Table: see text]

Neural peptide promotes the angiogenesis and osteogenesis around oral implants

Generally, impaired bones heal by bone repair and bone regeneration. These two processes are necessary during the healing period of dental implant. Vasculature plays a crucial role in bone healing because bones are highly vascularized tissue. Osteogenesis and angiogenesis are highly coupled processes and can be regulated by Hippo-YAP signaling pathway. Recent studies have demonstrated Hippo-YAP pathway may be regulated by alpha calcitonin gene-related peptide. However, the regulatory effects of αCGRP-YAP pathway on angiogenesis and osteogenesis during bone healing around implants remain unclear. Four groups of mice were established: KO Group: αCGRP ^-/- mice; KO + αCGRP group: αCGRP ^-/- mice with αCGRP overexpressing lentiviral transfection; KO + YAP group: αCGRP ^-/- mice with YAP overexpressing lentiviral transfection; WT group: wildtype mice. After 14 or 28 days, animals were sacrificed and tested. Results showed αCGRP deficiency hampered osteogenesis and angiogenesis. In addition, the impaired bone healing can be rescued by overexpressing αCGRP and YAP in αCGRP ^-/- mice. In-vivo results indicate αCGRP-YAP pathway promotes angiogenesis and osteogenesis in bone healing, especially at the early stage. Taken together, present study demonstrated αCGRP up-regulate the expression of YAP, and down-stream genes to promote the osteogenesis and angiogenesis around the implants.

Herpes zoster during arsenic trioxide therapy for acute promyelocytic leukemia

Historically, arsenic exposure has been associated with herpes zoster (HZ) infection, however the risk is not well characterized in arsenic trioxide (ATO) treated patients with acute promyelocytic leukemia (APL). We aimed to characterize the risk of HZ in 112 ATO treated patients with APL with and without antiviral prophylaxis (AVP). HZ occurred in 13/112 (11.6%) within 6 months of completing ATO, including one case of HZ encephalitis. AVP reduced the incidence of HZ (17.5% vs. 4.1%, RR 0.24 [95% CI 0.05-1.0, p = .025]) with a number needed to treat of 7.7. HZ despite AVP occurred later than HZ in patients without AVP (7.8 vs. 2.3 months from starting ATO, p = .11). Older age and prior HZ increased the risk of HZ in patients not receiving AVP. Routine AVP should be considered in patients with APL receiving ATO, particularly in older patients and those with a history of HZ.

Pesticide-derived bright chlorine-doped carbon dots for selective determination and intracellular imaging of Fe(III)

Inspired by the conversion from organics or biomass to fluorescent carbon dots (C-dots), the use of pesticide 4-chlorophenol (4-CP) as a precursor to prepare C-dots has been reported. The as-prepared chlorine-doped C-dots display a brightly blue emission at ∼445 nm with ∼22.8% quantum yield. Also, the surface of C-dots enriches functional groups, such as phenolic hydroxyl and carboxylic acid, etc., which can capture ferric ion (Fe(III)), resulting in the quenching of blue fluorescence of C-dots through an inner filter effect. The quantitative assay for Fe(III) was therefore realized by this probe with a 0.36 μM detection limit in the 0.6-25 μM concentration range. Most significantly, the cytotoxicity on Hela cells indicates the 4-CP-derived C-dots have a negligible cytotoxicity. The C-dots were applied in detection in environmental samples and imaging in Hela cells of Fe(III), demonstrating their good applicability, low toxicity and good biocompatibility, and providing an alterative approach to totally eliminate the harm of chlorophenols (CPs).

[Value of dual-energy CT-based volumetric iodine-uptake in the evaluation of chemotherapy efficacy in advanced gastric cancer]

Objective: To explore the value of dual-energy CT-based volumetric iodine-uptake (VIU) in the evaluation of chemotherapy efficacy in advanced gastric cancer. Methods: Inclusion criteria of subjects: (1) without previous systematic therapy; (2) with complete clinical information before and after chemotherapy; (3) without contraindications of chemotherapy. Exclusion criteria of subjects: (1) unfinished duration and times of chemotherapy; (2) unmeasurable primary lesions; (3) poor imaging quality or poor gastric filling. Clinical and image data of 52 patients with advanced gastric cancer who were diagnosed by pathology from gastroscopic biopsy, and needed chemotherapy evaluated by imaging and clinical information in the First Affiliated Hospital of Wenzhou Medical University from February 2017 to February 2018 were collected and analyzed. Of 52 patients, 38 were male and 14 were female with the median age of 65 (31-88) years old. All the patients underwent a dual-energy, dual phase-enhanced CT scanning before chemotherapy and after the third chemotherapy session. The parameters of the lesions measured before and after chemotherapy in portal vein phase were as follows: the maximum diameter (the largest diameter among those measured in the cross-sectional, coronal, and sagittal planes), average CT value (the regions of interest were manually pinpointed under cross-sectional planes with largest diameter of the tumor, which did not include regions less than 2 mm to the edge of the tumor) and VIU (lesion volume × iodine concentration). The change rates of maximum lesion diameter, average CT value and VIU before and after chemotherapy were calculated [(post-chemotherapy parameters-pre-chemotherapy parameters)/ pre-chemotherapy parameters]. The efficacy of chemotherapy was evaluated by RECIST 1.1 (the change of maximum tumor diameter after chemotherapy), Choi (the change of average CT value after chemotherapy) and VIU (the change of VIU after chemotherapy), respectively, which was categorized by complete response (CR), partial response (PR), stable disease (SD) and progressive disease (PD). Patients with CR, PR, and SD were assigned to the effective group, while those with PD were classified as the ineffective group. Paired t - test or Wilcoxon signed ranks test was used to compare the changes of parameters before and after chemotherapy, whereas Spearman correlation analysis and Kappa test were used for the correlation analysis and the consistency test between the three evaluation criteria (Kappa≥0.75 indicated good consistency). Results: After chemotherapy, the average CT value [(74.01±16.75) HU vs. (81.06±15.87) HU, t=2.202, P=0.030] and median VIU (668.53×10(2) μg vs. 272.52×10(2) μg, Z=4.761, P<0.001) decreased significantly, while the difference of the maximum diameter was not statistically significant [(66.71±34.49) mm vs. (78.45±35.62) mm, t=1.708, P=0.091]. The median change rate of VIU (-53.33%) was greater than that of CT values (-5.75%) with significant difference (Z=-5.408, P<0.001). According to the RECIST 1.1 criteria, 47 patients (90.4%, including 19 with PR and 28 with SD) were effective and 5 patients (9.6%) were ineffective. According to the Choi criteria, 45 patients (86.5%, including 37 with PR and 8 with SD) were effective and 7 patients (13.5%) were ineffective. According to the VIU criteria, 46 patients (88.5%, including 41 with PR and 5 with SD) were effective and 6 patients (11.5%) were ineffective. Efficacy comparison among these three criteria showed no significant difference (χ(2)=0.377, P=0.828). As compared to RECIST 1.1 evaluation, the proportion of PR evaluated by Choi and VIU was significantly higher (χ(2)=16.861, P<0.001), whereas the proportion of SD was significantly lower (χ(2)=24.089, P<0.001). There was no significant difference in the proportions of PR and SD between VIU and Choi criteria (χ(2)=0.887, P=0.346). Consistency and correlation analysis showed that the VIU and Choi evaluation criteria presented the highest consistency and correlation (Kappa=0.912, P<0.001; r=0.916, P<0.001). Conclusion: VIU is a feasible parameter for the evaluation of chemotherapy efficacy in advanced gastric cancer, and may be more sensitive than the evaluation criteria based on maximum diameter or change of CT value in the tumor.

Apical U-shape splitting technique for undercut areas of the anterior alveolar ridge: a prospective non-randomized controlled study

The aim of this study was to investigate a novel apical U-shape splitting technique for horizontal bone augmentation in undercut areas and to compare its efficacy with that of guided bone regeneration (GBR). This was a prospective non-randomized controlled clinical trial. A total of 36 patients, who presented with a labial undercut that was not able to house a normally inclined implant, underwent the new technique or GBR. Radiographic and clinical data were obtained preoperatively, immediately after surgery, and 12 months after surgery. Pairwise comparisons of changes in ridge width gain, marginal bone loss, and pink aesthetic score were performed; correlations with pristine ridge morphology were investigated. The results showed similar marginal bone loss in the two groups. The overall ridge width gains in the new technique group (2.56±1.92mm) and GBR group (0.73±1.21mm) differed significantly (P<0.05). The pink aesthetic score was higher for the new technique group (11.75±1.22) than for the GBR group (9.25±1.86) (P<0.01). The morphology of the concavity had different impacts on regeneration in the two groups. The apical U-shape splitting technique, as a safe and effective alternative to GBR, provided a significant increase in bone volume gain where labial fenestration was inevitable during implant placement.

A palatal roll envelope technique for peri-implant mucosa reconstruction: a prospective case series study

The aim of this study was to evaluate peri-implant soft tissue changes after performing a palatal roll envelope technique. Twelve patients, presenting a labial flat or concave profile before second-stage surgery, underwent soft tissue augmentation using the palatal roll envelope technique with papilla reservation design. The convex profile on the facial aspect, Jemt papilla index, facial mucosal level, marginal bone level, proximal bone levels of the adjacent teeth, and surgical/prosthetic complications were evaluated before surgery as the baseline, and then reevaluated at 1 week, 3 months, and 6 months after surgery. Data were analyzed using the Friedman test and Wilcoxon signed-rank test. Results indicated that the convex profile and the average papilla index score were improved, while the facial mucosal level was adjusted to a level similar to that of the contralateral tooth at 3 months and then remained stable for the follow-up visit. With the limitations identified in this report, the palatal roll envelope technique can be considered an alternative method to augment the soft tissue during second-stage surgery. This technique obviates the need for another surgical site and papillae area, and also reduces the risks of graft shrinkage and scarring on the labial site.

Knockdown of AXL receptor tyrosine kinase in osteosarcoma cells leads to decreased proliferation and increased apoptosis

Dysregulation of the Axl receptor tyrosine kinase (RTK) has been implicated in the development and progression of a variety of malignancies. Axl is known to activate strong anti-apoptotic signaling pathways that promote oncogenesis. However, the role of Axl plays in osteosarcoma (OS) remains elusive. The present study aimed to investigate the clinical significance and function of Axl in human OS. Forty cases of OS and corresponding adjacent non-cancerous tissues (ANCT) were collected. The expression of Axl was assessed using immunohistochemical assay through tissue microarray procedure. A loss-of-function experiment was performed to investigate the effects of small hairpin RNA (shRNA)-mediated knockdown of Axl on the expression of p-AKT, poly ADP-ribose polymerase (PARP) and Ki-67, the proliferative activities, indicated by MTT assay, and the apoptotic index in OS MG-63 cells. As a result, the expression of Axl was found in OS tissues with higher strong reactivity rate, compared with the ANCT (75.0 percent vs 20.0 percent, P=0.000), but it did not associate with the age, gender, tumor size, TNM staging and distant metastases (each Pgreater than0.05). Furthermore, knockdown of Axl inhibited the proliferative activities and induced apoptosis in MG-63 cells with decreased expression of p-AKT, and Ki-67 and increased expression of PARP. In conclusion, our findings suggest that Axl is highly expressed in most of the OS tissues compared with the ANCT, and knockdown of Axl inhibits proliferation and induces apoptosis of OS cells possibly through downregulation of the AKT pathway, suggesting that our findings may provide new insights into the potential therapeutic target for cancer.

Defect modes in one-dimensional granular crystals

We study the vibrational spectra of one-dimensional statically compressed granular crystals (arrays of elastic particles in contact) containing light-mass defects. We focus on the prototypical settings of one or two spherical defects (particles of smaller radii) interspersed in a chain of larger uniform spherical particles. We present a systematic measurement, using continuous noise, of the near-linear frequency spectrum within the spatial vicinity of the defect(s). Using this technique, we identify the frequencies of the localized defect modes as a function of the defect size and the position of the defects relative to each other. We also compare the experimentally determined frequencies with those obtained by numerical eigenanalysis and by analytical expressions based on few-site considerations. These approximate analytical expressions, based on normal-mode analysis, are found to be in excellent agreement with numerics for a wide range of mass ratios. We also observe that the experimentally measured frequencies of the localized defect modes are uniformly upshifted, compared to the numerically and theoretically predicted values.

CAPC expression correlates with breast tumor progression and invasion

Abstract #4044

Background: Recent studies identified a uncharacterized gene that encodes a molecule named as cytokeratin-associated protein in cancer (CAPC). RT-PCR analysis detected significant elevation of CAPC mRNA in 26 of 33 human breast cancers. Our current study attempted to elucidate CAPC protein expression profile in human breast tissues, to assess: [1] if CAPC expression is associated with tumor progression and invasion, and [2] if CAPC is co-expressed with BP1 and c-erbB2, two known invasiveness and aggressiveness-related proteins.&#x2028; Materials and Methods: Consecutive sections were prepared from paraffin-embedded breast tissues from 100 female patients with breast tumors that harbored co-existing normal, hyperplastic, in situ, and invasive components. Sets of four adjacent sections from each case were subjected to immunohistochemistry for CAPC, BP1, c-erbB2, and Ki-67. The expression status of these molecules in different tissue components were statistically compared.&#x2028; Results: In normal breasts and hyperplastic or in situ breast lesions, CAPC positive cells were generally distributed as duct or acinar clusters with a distinct boundary with their CAPC negative counterparts. Under low magnification of H&E stained sections, these CAPC positive duct or acinar clusters were morphologically indistinguishable from their CAPC negative counterparts. Under high magnification, however, the myoepithelial cell layers of these CAPC positive clusters were focally disrupted, and the associated epithelial cells often showed malignancy-associated nuclear alterations. Both the number of CAPC positive cells and the intensity of CAPC immunostaining linearly increased with tumor progression and invasion. In invasive lesions, a vast majority of cancer cells in over 80% of the cases expressed high levels of CAPC. A majority of the normal, benign, and malignant tumors with high levels of CAPC showed substantially higher expression of BP1 and c-erbB2, along with a higher proliferation index, compared to their morphologically similar CAPC negative counterparts . In non-mitotic cells, CAPC was localized mainly in the cytoplasm. In malignant mitotic cells, high levels of CAPC expression were localized close to the cell membrane, forming a ring-like structure surrounding condensed chromosomes. In contrast, no distinct CAPC was detected in normal or hyperplastic mitotic cells.&#x2028; Discussion: These findings suggest CAPC might be a tumor specific marker that could be used for the development of diagnostic and/or therapeutic agents.&#x2028; Acknowledgment: Supported in part by grant BCTR0706983 from The Susan G. Komen Breast Cancer Foundation and grant 2006CB910505 from the Ministry of Chinese Science and Technology Department.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 4044.

Maintenance of the epithelial barrier in a bronchial epithelial cell line is dependent on functional E-cadherin local to the tight junctions

Tight junctions (TJ) are essential components of polarized epithelia, and E-cadherin is important for their formation and maintenance. The bronchial epithelial cell line, 16HBE14o-expresses E- and P-cadherin, but not N-cadherin. E- and P-cadherin levels changed during culture, the former increasing after confluence, and the latter were markedly reduced. All detectable E-cadherin was bound to beta- and gamma-catenins. We investigated involvement of E-cadherin with epithelial integrity using an E-cadherin specific, function-blocking antibody, SHE78-7. Surprisingly, apical SHE78-7 exposure caused a prompt fall in transepithelial resistance (TER), while TER remained unchanged for 8 hrs after basal exposure then dropped. SHE78-7 exposure increased epithelial permeability to mannitol, inulin, and 9.5 kDa and 77 kDa dextrans and caused fragmentation and loss of the tight junction protein, ZO-1, from the cell borders in some areas. Ultrastructural studies showed that all junctional intercellular contact was lost in the center of SHE78-7 induced lesions. Near the lesion periphery, epithelial structure was maintained, but TJs were dysfunctional as shown by ruthenium red penetration. Analysis of epithelial penetration by SHE78-7 revealed discrete, local defects in the apical barrier at the top of some cell hills that permitted rapid access of the antibody to E-cadherin near the apical surface. In contrast, after basal exposure, antibody initially engaged with E-cadherin nearer the basal surface and only accessed apical E-cadherin later. Taken together with the TER measurements, these data suggest compartmentalization of E-cadherin function within 16HBE14o-cells, with only the apical E-cadherin adjacent to the tight junctions contributing to the function of the latter.

Allelic losses at 3p and 11p are detected in both epithelial and stromal components of cervical small-cell neuroendocrine carcinoma

Microdissected epithelial and stromal cells from 15 cervical small-cell carcinoma patients and 9 healthy control subjects were assessed for loss of heterozygosity with polymorphic DNA markers at chromosomes 3p and 11p. Among malignant lesions assessed with 7 markers at 3p, 21 allelic losses were detected from 193 informative samples. Of losses, 20 were in epithelial and 1 was in normal-appearing stromal cells. Among losses in epithelial cells, 16 were from 44 samples informative for 3 markers within 3p21.2-p14.2 (0.36 loss/sample), whereas only 4 were from 54 samples informative for 4 markers outside the region (0.09 loss/sample), suggesting a "hot spot" of genetic alterations within 3p21.2-p14.2. Among malignant lesions assessed with 2 markers within 11p14-p12, 15 losses were seen in 52 informative samples. Of losses, 10 were in epithelial and 5 were in normal-appearing stromal cells. Of 10 epithelial samples showing losses within 11p14-p12, 8 also displayed losses within 3p21.2-p14.2, suggesting a concurrent involvement of these loci in tumor development or progression. The five losses in stromal cells were in four cases that showed no loss in epithelial cells with same markers, suggesting that stromal cells might play initiative roles in tumor development.

Loss of epithelial integrity resulting from E-cadherin dysfunction predisposes airway epithelial cells to adenoviral infection

Epithelial intercellular adhesion is fundamental to the formation of the airway epithelial protective barrier. In this respect, cadherins are important because these adhesion molecules regulate formation and maintenance of epithelial intercellular junctions. To study the importance of airway epithelial integrity in determining susceptibility to virus infection, we used a replication-incompetent adenovirus, RAd35, and an E-cadherin specific function-blocking antibody, SHE78-7, to disrupt intercellular contacts in human bronchial epithelial cell line 16HBE14o- and primary bronchial epithelial cells. After exposure of 16HBE14o- cell cultures to SHE78-7, disruption of the transepithelial permeability barrier was indicated by a loss of transepithelial electrical resistance and an associated increase of mannitol, inulin, and dextran paracellular flux. Subsequent exposure of SHE78-7-treated cell cultures to RAd35 showed a remarkable increase in adenoviral infection as assessed by beta-galactosidase reporter gene expression. In cultures exposed to SHE78-7, disruption of E-cadherin function resulted in infection equivalent to that in control cultures using 16-fold lower viral titers. These studies show that manipulation of E-cadherin function provides a specific means of altering epithelial integrity that in turn determines resistance of airway epithelia to adenoviral infection.

Five useful approaches for generating more valid gel images of loss of heterozygosity and clonality analysis with an automated 377 DNA sequencer

The recently introduced fluorescence-based gene scan system for assessment of loss of heterozygosity (LOH) and clonality with an automated DNA sequencer has several advantages over the traditional method. However, the production of gel images with this system is subjected to more technical challenges, including the interference of autofluorescence, weaker and less consistent signals that result from the restricted well size and difficulties in sample loading. To minimize the impact of these technical difficulties, several unique strategies were used, including the following: elimination of fabrics or paper towels in the cleaning of gel plates and containers; use of a modified loading buffer; use of more concentrated gels; use of an innovative apparatus to clean gel wells before and after the prerun; and covering the black printer cartridge with a sheet of scotch tape. With these strategies, the authors have been able to consistently obtain gel images that can be presented as either densitometric graphs or as band patterns for direct visual assessment.

Loss of heterozygosity is detected at chromosomes 1p35-36 (NB), 3p25 (VHL), 16p13 (TSC2/PKD1), and 17p13 (TP53) in microdissected apocrine carcinomas of the breast

INTRODUCTION

Apocrine carcinomas of the breast are an unusual special category of predominantly AR+, ER-, and PR- breast cancer, characterized by cells with abundant, eosinophilic cytoplasm and nuclei with often prominent nucleoli. To further investigate these lesions, loss of heterozygosity (LOH) was evaluated at multiple chromosomal loci, including loci frequently mutated in breast cancer.

MATERIALS AND METHODS

Twenty-five intraductal apocrine carcinomas, 11 invasive apocrine carcinomas, and six apocrine hyperplasias were retrieved from the files of the Armed Forces Institute of Pathology (Washington, DC) and Fairfax Hospital (Fairfax, VA). Cells from lesional as well as normal tissues were microdissected. LOH was performed at a number of chromosomal loci, including loci commonly altered in breast cancer: 1p35-36 (NB), 3p25.5 (VHL), 8p12 (D8S136), 9p21 (p16), 11p13 (D11S904), 11q13 (INT-2 and PYGM), 16p13.3 (TSC2/PKD1 gene region), 17p13 (TP53), 17q13 (NM23), and 22q12 (D22S683).

RESULTS

Among informative in situ and invasive apocrine carcinomas, LOH was present in 33% of 15 cases for 17p13 (TP53), as well as 36% of 14 cases for 3p25 (VHL), 30% of 10 cases for 1p35-36 (NB), and 27% of 11 cases for 16p13.3 (TSC2/PKD1). A higher frequency of LOH was noted among invasive apocrine carcinomas (30 to 50%) compared with in situ apocrine carcinomas (23 to 33%) at these loci. LOH was present simultaneously for TP53 and either VHL or NB in five cases. Infrequent (< or =12%) or absent LOH was detected at the remaining loci, including several loci commonly mutated in breast cancer (i.e., INT2, PYGM, and NM23). LOH was not detected in any of the six apocrine hyperplasias.

CONCLUSION

An intermediate frequency of allelic loss was detected at multiple tumor suppressor gene loci, including 17p13 (TP53), as well as 1p35-336 (NB), 3p25 (VHL), and 16p13 (PKD1/ TSC2), in apocrine carcinomas of the breast, with a higher overall frequency of LOH noted among invasive tumors compared with in situ tumors. Aside from LOH at p53, LOH was infrequent or absent at several other loci commonly mutated in breast cancer. This preliminary molecular evidence supports immunohistochemical data that apocrine carcinomas of the breast may possess unique mechanisms of carcinogenesis, compared with ordinary ductal carcinomas. However, further study is needed to support this assertion and to determine if the LOH detected is truly etiologic or if it is the result of genetic progression.

Picumeterol: dissociation of improvement in lung function and reduction of airways hyperresponsiveness in asthmatics

AIMS

The new potent and selective beta 2-adrenoceptor agonist, GR 114297A (picumeterol) is the R-enantiomer of the racemic form, GR 63411B. Picumeterol has been shown to produce long-lasting relaxation of airways smooth muscle both in vitro and in vivo. We assessed the intrinsic activity of picumeterol by increasing intracellular levels of c-AMP and compared this with isoprenaline and salbutamol.

METHODS

In human atopic asthmatics, we have investigated the duration of action and efficacy of picumeterol and GR 63411B with regard to improvement in resting lung function (i.e. FEV1) and airways responsiveness (i.e. PC20) to methacholine (MCh). The study design consists of two clinical parts each for one drug. Different asthmatics participated in the two studies, seven in the first part and eight in the second part. In human bronchial smooth muscle cells in vitro, we have investigated the intrinsic activity of picumeterol in increasing intracellular levels of cyclic AMP and compared it with isoprenaline and salbutamol.

RESULTS

In vivo, both drugs caused bronchodilatation with similar potency, but, their effects were short-lasting. Despite their bronchodilator activity, neither drug improved PC20, when compared with placebo. In vitro, picumeterol was found have intrinsic activity lower than the other beta 2-adrenoceptor agonists tested.

CONCLUSIONS

In the clinical studies, the bronchodilator potencies of picumeterol and GR 63411B were similar. However, both drugs were short-acting, which is at odds with their activity in vitro. Our data suggest that these compounds display dissociation between bronchodilator activity and protection against MCh-induced bronchoconstriction. These findings may be explained by low intrinsic activity and need further conformation.

Two nonradioactive assays for phosphotyrosine phosphatases with activity toward the insulin receptor

Two highly sensitive, nonradiolabeled assays for protein phosphotyrosine phosphatase (PTPase) have been developed. The first assay is based on the use of chemically synthesised phosphotyrosine-containing peptides that can be separated from the dephosphorylated peptide products by HPLC. In this assay, partially purified placental PTPase 1B dephosphorylated three dodecaphosphopeptides (corresponding to insulin receptor autophosphorylation sites at positions PY1146, PY1150, and PY1151) with approximately equal affinity (Km 1.3-2.5 microM), indicating that PTPase 1B shows no distinct preference for the site of dephosphorylation in these peptides. The second assay employs either a phosphopeptide or an autophosphorylated tyrosine kinase domain immobolized on microtiter plate wells. After reaction with PTPase, the remaining unconverted phosphosubstrate is detected in an ELISA using anti-phosphotyrosine antibodies. The latter assay was used to monitor PTPase activity during purification procedures and for characterizing PTPases. Modulation of PTPase activity by orthovanadate, heparin, Zn2+, and EDTA gave similar results in both assays. The immobilized autophosphorylated IR tyrosine kinase domain was a poor substrate for bovine liver alkaline phosphatase and seminal fluid acid phosphatase. The second assay also offers the potential for comparing PTPase activity toward several autophosphorylated tyrosine kinase domains, including those of the insulin, epidermal growth factor, and platelet-derived growth factor receptors.