Facial nerve recording from the eardrum: a possible method for evaluating idiopathic facial nerve paralysis

A noninvasive technique has been developed for recording from the the facial nerve within the fallopian canal. Following transcutaneous stimulation of the nerve on the face, an antidromic nerve potential can be detected with electrodes placed on the eardrum and enhanced by the technique of averaging. In studies conducted on cats and normal human subjects it has been determined that the primary recording site of the nerve potential is along the tympanic segment of the nerve just distal to the geniculate ganglion. Disturbances in nerve conduction caused by an experimental lesion produced changes in the recorded nerve potential. Thus it seems likely that this technique could assess a developing lesion in a patient with idiopathic facial nerve paralysis. A more accurate and earlier prognosis could be obtained than with conventional peripheral nerve testing techniques, since the severity of the developing lesion itself could be assessed.     

A study of post-operative sensitivity in class I and class II restorations with self-etching adhesive and nanofilled composite

AIM: The aim of the study was to determine the type, intensity and duration of post operative sensitivity (POS) in class I and II cavity restorations with self-etching adhesive and nanofilled composite. PATIENTS AND METHODS: The clinical study included 34 patients, who received a total of 76 restorations by undergraduate dental students. The restorations were made in medium and deep cavities. Self-etching adhesive Adper Promp L-Pop and nanocomposite Filtek Supreme (3MESPE Dental products USA) were placed. The type, the magnitude and the duration of postoperative sensitivity were examined on days 1, 3, 5, 7, 14 and 30. Intensity of sensitivity perceptions were recorded on a visual analogue scale using the method of self-observation. Parametric and non-parametric analyses were employed at a significance level of P < 0.05. RESULTS: Pressure-dependent POS was present in most of the cases (15.78% +/- 4.209), followed by discomfort (9.21% +/- 3.340) and pressure- and cold-induced pain (1.33% +/- 1.147). A statistically significant difference was found between days 1 and 3, and between days 5 and 30, as well as between days 7 and 30 (Wilcoxon Signed Ranks Test, P < 0.05). Rapidly disappearing POS (within 1 week) had the highest percentage: 75% +/- 9.934. CONCLUSIONS: Following restoration of class I and II cavities with self-etching adhesive and nanofilled composite POS was established in 26.3% of the cases.     

Flt3L therapy following localized tumor irradiation generates long-term protective immune response in metastatic lung cancer: its implication in designing a vaccination strategy

Flt3 ligand (Flt3L) therapy that expands dendritic cells in vivo in combination with local tumor radiotherapy (RT) significantly improved survival and induced a long-term tumor-specific immune response in a murine model of Lewis lung carcinoma (3LL). The irradiated tumor cells were able to significantly restimulate the splenocytes of the RT + Flt3L cohort in vitro. The restimulated splenocytes demonstrated increased cytotoxic response, lymphocytic proliferation and elevated levels of Th type I cytokines (IL-2, IL-12, IFN-gamma and TNF-alpha). The combination therapy of RT + Flt3L induced a long-term protective immunity in the disease-free animals. The protective effect was further enhanced when the disease-free animals were vaccinated with irradiated tumor cells. The vaccinated animals had significantly greater protection compared to the nonvaccinated group against subsequent challenge with 3LL cells. Taken together, these results indicate that the release of tumor antigens by irradiated dying tumors and concomitant administration of Flt3L was able to facilitate the generation of a tumor-specific long-term immune response against a poorly immunogenic tumor. This effect was further boosted by vaccination with irradiated tumor cells.     

Intratumoral cytokines/chemokines/growth factors and tumor infiltrating dendritic cells: friends or enemies?

The tumor microenvironment consists of a variable combination of tumor cells, stromal fibroblasts, endothelial cells and infiltrating leukocytes, such as macrophages, T lymphocytes, and dendritic cells. A variety of cytokines, chemokines and growth factors are produced in the local tumor environment by different cells accounting for a complex cell interaction and regulation of differentiation, activation, function and survival of multiple cell types. The interaction between cytokines, chemokines, growth factors and their receptors forms a comprehensive network at the tumor site, which is primary responsible for overall tumor progression and spreading or induction of antitumor immune responses and tumor rejection. Although the general thought is that dendritic cells are among the first cells migrating to the tumor site and recognizing tumor cells for the induction of specific antitumor immunity, the clinical relevance of dendritic cells at the site of the tumor remains a matter of debate regarding their role in the generation of successful antitumor immune responses in human cancers. While several lines of evidence suggest that intratumoral dendritic cells play an important role in antitumor immune responses, understanding the mechanisms of dendritic cell/tumor cell interaction and modulation of activity and function of different dendritic cell subtypes at the tumor site is incomplete. This review is limited to discussing the role of intratumoral cytokine network in the understanding immunobiology of tumor-associated dendritic cells, which seems to possess different regulatory functions at the tumor site.     

Monitoring protein stability and aggregation in vivo by real-time fluorescent labeling

In vivo fluorescent labeling of an expressed protein has enabled the observation of its stability and aggregation directly in bacterial cells. Mammalian cellular retinoic acid-binding protein I (CRABP I) was mutated to incorporate in a surface-exposed omega loop the sequence Cys-Cys-Gly-Pro-Cys-Cys, which binds specifically to a biarsenical fluorescein dye (FlAsH). Unfolding of labeled tetra-Cys CRABP I is accompanied by enhancement of FlAsH fluorescence, which made it possible to determine the free energy of unfolding of this protein by urea titration in cells and to follow in real time the formation of inclusion bodies by a slow-folding, aggregationprone mutant (FlAsH-labeled P39A tetra-Cys CRABP I). Aggregation in vivo displayed a concentration-dependent apparent lag time similar to observations of protein aggregation in purified in vitro model systems.     

Significant differences in B-cell subpopulations characterize patients with chronic graft-versus-host disease-associated dysgammaglobulinemia

Manifestations of chronic graft-versus-host disease (cGVHD) can resemble those seen in immunodeficiency states and autoimmune disorders. Reports by us and others suggest an involvement of B cells in the pathogenesis of cGVHD. We investigated B-lymphocyte subpopulations in cGVHD cohorts defined by serum immunoglobulin G (IgG) levels to characterize novel biomarkers for impairment of humoral immunity after allogeneic hematopoietic stem cell transplantation. Seventy-six patients were enrolled a median of 46 months after hematopoietic stem cell transplantation. The hypogammaglobulinemia group had significantly diminished CD19(+) B cells (165 vs 454 vs 417 × 10?L) with elevated CD19(+)CD21(low) immature (16.5%, 7.7%, and 9.1%) and CD19(+)CD21(int-high)CD38(high)IgM(high) transitional (10.5% vs 4.2% vs 6.3%) B-cell proportions compared with the normogammaglobulinemia and hypergammaglobulinemia groups. CD19(+)CD10(-)CD27(-)CD21(high) naive B cells were highly elevated in all patients with cGVHD. CD19(+)CD27(+)IgD(+) non-class-switched (4 vs 12 vs 11 × 10?/L) and class-switched (7 vs 35 vs 42 × 10?/L) memory B cells were significantly lower in the hypogammaglobulinemia group compared with the others. Besides significantly higher B-cell activation factor/B-cell ratios, significantly more cGVHD patients with hypergammaglobulinemia had autoantibodies compared with the hypogammaglobulinemia subgroup (68% vs 24%, P = .024). In conclusion, B-cell subpopulations can serve as novel cellular biomarkers for immunodeficiency and autoimmunity indicating different pathogenetic mechanisms of cGVHD and encouraging future prospective longitudinal studies.     

The Arabidopsis homolog of trithorax, ATX1, binds phosphatidylinositol 5-phosphate, and the two regulate a common set of target genes

The Arabidopsis homolog of trithorax, ATX1, regulates numerous functions in Arabidopsis beyond the homeotic genes. Here, we identified genome-wide targets of ATX1 and showed that ATX1 is a receptor for a lipid messenger, phosphatidylinositol 5-phosphate, PI5P. PI5P negatively affects ATX1 activity, suggesting a regulatory pathway connecting lipid-signaling with nuclear functions. We propose a model to illustrate how plants may respond to stimuli (external or internal) that elevate cellular PI5P levels by altering expression of ATX1-controlled genes.     

Predicting the likelihood of an isocitrate dehydrogenase 1 or 2 mutation in diagnoses of infiltrative glioma

Background

Several variables are associated with the likelihood of isocitrate dehydrogenase 1 or 2 (IDH1/2) mutation in gliomas, though no guidelines yet exist for when testing is warranted, especially when an R132H IDH1 immunostain is negative.

Methods

A cohort of 89 patients was used to build IDH1/2 mutation prediction models in World Health Organization grades II–IV gliomas, and an external cohort of 100 patients was used for validation. Logistic regression and backward model selection with the Akaike information criterion were used to develop prediction models.

Results

A multivariable model, incorporating patient age, glioblastoma multiforme diagnosis, and prior history of grade II or III glioma, was developed to predict IDH1/2 mutation probability. This model generated an area under the curve (AUC) of 0.934 (95% CI: 0.878, 0.978) in the external validation cohort and 0.941 (95% CI: 0.918, 0.962) in the cohort of The Cancer Genome Atlas. When R132H IDH1 immunostain information was added, AUC increased to 0.986 (95% CI: 0.967, 0.998). This model had an AUC of 0.947 (95% CI: 0.891, 0.995) in predicting whether an R132H IDH1 immunonegative case harbored a less common IDH1 or IDH2 mutation. The models were also 94% accurate in predicting IDH1/2 mutation status in gliomas from The Cancer Genome Atlas. An interactive web-based application for calculating the probability of an IDH1/2 mutation is now available using these models.

Conclusions

We have integrated multiple variables to generate a probability of an IDH1/2 mutation. The associated web-based application can help triage diffuse gliomas that would benefit from mutation testing in both clinical and research settings.     

Diagnosing breast cancer using diffuse reflectance spectroscopy and intrinsic fluorescence spectroscopy

Using diffuse reflectance spectroscopy and intrinsic fluorescence spectroscopy, we have developed an algorithm that successfully classifies normal breast tissue, fibrocystic change, fibroadenoma, and infiltrating ductal carcinoma in terms of physically meaningful parameters. We acquire 202 spectra from 104 sites in freshly excised breast biopsies from 17 patients within 30 min of surgical excision. The broadband diffuse reflectance and fluorescence spectra are collected via a portable clinical spectrometer and specially designed optical fiber probe. The diffuse reflectance spectra are fit using modified diffusion theory to extract absorption and scattering tissue parameters. Intrinsic fluorescence spectra are extracted from the combined fluorescence and diffuse reflectance spectra and analyzed using multivariate curve resolution. Spectroscopy results are compared to pathology diagnoses, and diagnostic algorithms are developed based on parameters obtained via logistic regression with cross-validation. The sensitivity, specificity, positive predictive value, negative predictive value, and overall diagnostic accuracy (total efficiency) of the algorithm are 100, 96, 69, 100, and 91%, respectively. All invasive breast cancer specimens are correctly diagnosed. The combination of diffuse reflectance spectroscopy and intrinsic fluorescence spectroscopy yields promising results for discrimination of breast cancer from benign breast lesions and warrants a prospective clinical study.