Dynamic behaviour of the soft palate during nasal positive pressure ventilation under anaesthesia and paralysis: comparison between patients with and without obstructive sleep-disordered breathing.

BACKGROUND: Difficult mask ventilation is common and is known to be associated with sleep-disordered breathing (SDB). It is our hypothesis that the incidence of expiratory retropalatal (RP) airway closure (primary outcome) during nasal positive pressure ventilation (PPV) is more frequent in patients with SDB (apnea hypopnea index ≥5 h-1) than non-SDB subjects. METHODS: The severity of SDB was assessed before surgery using a portable sleep monitor. In anaesthetized and paralysed patients with (n=11) and without SDB (n=9), we observed the behaviour of the RP airway endoscopically during nasal PPV with the mouth closed and determined the dynamic RP closing pressure, which was defined as the highest airway pressure above which the RP airway closure was reversed. The static RP closing pressure was obtained during cessation of mechanical ventilation in patients with dynamic RP closure during nasal PPV. RESULTS: The expiratory RP airway closure accompanied by expiratory flow limitation occurred more frequently in SDB patients (9/11, 82%) than in non-SDB subjects (2/9, 22%; exact logistic regression analysis: P=0.022, odds ratio 3.6, 95% confidence interval 1.1-15.4). Receiver operating characteristic curve analyses indicated AHI >10h-1 and presence of habitual snoring as clinically useful predictors for the occurrence of RP closure during PPV. Dynamic RP closing pressure was greater than the static RP closing pressure by approximately 4-5 cm H2O. CONCLUSIONS: Valve-like dynamic RP closure that limits expiratory flow during nasal PPV occurs more frequently in SDB patients.

Comparison of electrochemiluminescence immunoassay and latex agglutination turbidimetric immunoassay for evaluation of everolimus blood concentrations in renal transplant patients.

WHAT IS KNOWN AND OBJECTIVE: For analysis of blood concentrations of everolimus, many hospital laboratories use either latex agglutination turbidimetric immunoassay (LTIA) or electrochemiluminescence immunoassay (ECLIA). However, no studies have compared both immunoassay methods under the same conditions. Accordingly, in this study, we compared everolimus blood concentrations obtained by LTIA and ECLIA in renal transplant patients. METHODS: Blood samples (n = 230) from 60 renal transplant patients (19 female and 41 male) were evaluated using both immunoassays. Subsequently, we switched the assay for detection of everolimus blood concentrations from LTIA to ECLIA as a clinical application. Three quality control (QC) samples for LTIA were analysed using ECLIA, and 3 QC samples for ECLIA were analysed using LTIA. RESULTS: The Deming regression of ECLIA versus LTIA generated the following parameters: slope, 1.0067 and intercept, 1.7489 ng/mL, in the analysis of 230 samples. Bland-Altman analysis showed an average positive bias of 1.73 ng/mL between ECLIA and LTIA. When the clinical apparatus was switched from LTIA to ECLIA, the average everolimus blood concentration assayed by LTIA before switching was 3.57 ng/mL, whereas that by ECLIA after switching in the same patients taking the same daily dose (mean: 1.43 mg/day) was 5.85 ng/mL. The QCs assayed using LTIA were lower by an average of 67.3% (range: 55.8%-79.5%) for ECLIA, and in the same 230 samples from patients, the everolimus blood concentrations assayed by LTIA were lower by an average of 67.4% (range: 37.1%-114.5%) of ECLIA. WHAT IS NEW AND CONCLUSION: Analysis of everolimus concentrations by immunoassays with high precision and accuracy is required to ensure long-term survival of transplant recipients. Although the concentrations of QCs and calibrators of everolimus in LTIA were previously corrected to 70% concentration because of cross-reactivity with everolimus metabolites, these adjustments may need to be reviewed.

A multicenter retrospective study of the risk factors associated with medication-related osteonecrosis of the jaw after tooth extraction in patients receiving oral bisphosphonate therapy: can primary wound closure and a drug holiday really prevent MRONJ?

Root amputation, extraction of a single tooth, bone loss or severe tooth mobility, and an unclosed wound were significantly associated with increased risk of developing medication-related osteonecrosis of the jaw (MRONJ). We recommend a minimally traumatic extraction technique, removal of any bone edges, and mucosal wound closure as standard procedures in patients receiving bisphosphonates. INTRODUCTION: Osteonecrosis of the jaws can occur following tooth extraction in patients receiving bisphosphonate drugs. Various strategies for minimizing the risk of MRONJ have been advanced, but no studies have comprehensively analyzed the efficacy of factors such as primary wound closure, demographics, and drug holidays in reducing its incidence. The purpose of this study was to retrospectively investigate the relationships between these various risk factors after tooth extraction in patients receiving oral bisphosphonate therapy. METHODS: Risk factors for MRONJ after tooth extraction were evaluated using univariate and multivariate analysis. All patients were investigated with regard to demographics; type and duration of oral bisphosphonate use; whether they underwent a discontinuation of oral bisphosphonates before tooth extraction (drug holiday), and the duration of such discontinuation; and whether any additional surgical procedures (e.g., incision, removal of bone edges, root amputation) were performed. RESULTS: We found that root amputation (OR = 6.64), extraction of a single tooth (OR = 3.70), bone loss or severe tooth mobility (OR = 3.60), and an unclosed wound (OR = 2.51) were significantly associated with increased risk of developing MRONJ. CONCLUSIONS: We recommend a minimally traumatic extraction technique, removal of any bone edges, and mucosal wound closure as standard procedures in patients receiving bisphosphonates. We find no evidence supporting the efficacy of a pre-extraction short-term drug holiday from oral bisphosphonates in reducing the risk of MRONJ.

Assessing the progression of chronic periodontitis using subgingival pathogen levels: a 24-month prospective multicenter cohort study.

BACKGROUND: The diagnosis of the progression of periodontitis presently depends on the use of clinical symptoms (such as attachment loss) and radiographic imaging. The aim of the multicenter study described here was to evaluate the diagnostic use of the bacterial content of subgingival plaque recovered from the deepest pockets in assessing disease progression in chronic periodontitis patients. METHODS: This study consisted of a 24-month investigation of a total of 163 patients with chronic periodontitis who received trimonthly follow-up care. Subgingival plaque from the deepest pockets was recovered and assessed for bacterial content of Porphyromonas gingivalis, Prevotella intermedia, and Aggregatibacter actinomycetemcomitans using the modified Invader PLUS assay. The corresponding serum IgG titers were measured using ELISA. Changes in clinical parameters were evaluated over the course of 24 months. The sensitivity, specificity, and prediction values were calculated and used to determine cutoff points for prediction of the progression of chronic periodontitis. RESULTS: Of the 124 individuals who completed the 24-month monitoring phase, 62 exhibited progression of periodontitis, whereas 62 demonstrated stable disease. The P. gingivalis counts of subgingival plaque from the deepest pockets was significantly associated with the progression of periodontitis (p < 0.001, positive predictive value = 0.708). CONCLUSIONS: The P. gingivalis counts of subgingival plaque from the deepest pockets may be associated with the progression of periodontitis.

Systematic review and assessment of systematic reviews examining the effect of periodontal treatment on glycemic control in patients with diabetes.

OBJECTIVES: There have been several systematic reviews(SRs) on whether periodontal treatment for an individual with both periodontal disease and diabetes can improve diabetes outcomes. The purpose of this investigation was to conduct a systematic review (SR) of previous meta-analyses, and to assess the methodological quality of the SRs examining the effects of periodontal treatment and diabetes. (PROSPERO Registration # CRD 42015023470). STUDY DESIGN: We searched five electronic databases and identified previous meta-analyses of randomized controlled trials published through July 2015. In cases where the meta-analysis did not meet our criteria, the meta-analyses were recalculated. General characteristics of each included trial were abstracted, analyzed, and compared. The mean difference, 95% confidence intervals (CIs) and the I2 statistic were abstracted or recalculated. The Assessment of Multiple Systematic Reviews Instrument (AMSTAR) was used to assess methodological quality. RESULTS: Of the 475 citations screened, nine systematic reviews were included. In total, 13 meta-analyses included in nine SRs were examined. In comparability analyses, meta-analyses in four SRs did not meet our criteria, and were recalcuated. Of these 13 meta-analyses, 10 suggested significant effects of periodontal treatment on HbA1c improvement. Mean differences found in the 13 meta-analyses ranged from -0.93 to 0.13. AMSTAR assessment revealed six SRs with moderate and three with high overall quality. CONCLUSIONS: We can conclude that there is a significant effect of periodontal treatment on improvement of HbA1c in diabetes patients, although the effect size is extremely small. In addition to the small effect size, not all SRs could be considered of high quality.

Salivary pathogen and serum antibody to assess the progression of chronic periodontitis: a 24-mo prospective multicenter cohort study.

BACKGROUND AND OBJECTIVE: A diagnosis of periodontitis progression is presently limited to clinical parameters such as attachment loss and radiographic imaging. The aim of this multicenter study was to monitor disease progression in patients with chronic periodontitis during a 24-mo follow-up program and to evaluate the amount of bacteria in saliva and corresponding IgG titers in serum for determining the diagnostic usefulness of each in indicating disease progression and stability. MATERIAL AND METHODS: A total of 163 patients with chronic periodontitis who received trimonthly follow-up care were observed for 24 mo. The clinical parameters and salivary content of Porphyromonas gingivalis, Prevotella intermedia and Aggregatibacter actinomycetemcomitans were assessed using the modified Invader PLUS assay, and the corresponding serum IgG titers were measured using ELISA. The changes through 24 mo were analyzed using cut-off values calculated for each factor. One-way ANOVA or Fisher's exact test was used to perform between-group comparison for the data collected. Diagnostic values were calculated using Fisher's exact test. RESULTS: Of the 124 individuals who completed the 24-mo monitoring phase, 62 exhibited periodontitis progression, whereas 62 demonstrated stable disease. Seven patients withdrew because of acute periodontal abscess. The ratio of P. gingivalis to total bacteria and the combination of P. gingivalis counts and IgG titers against P. gingivalis were significantly related to the progression of periodontitis. The combination of P. gingivalis ratio and P. gingivalis IgG titers was significantly associated with the progression of periodontitis (p = 0.001, sensitivity = 0.339, specificity = 0.790). CONCLUSIONS: It is suggested that the combination of P. gingivalis ratio in saliva and serum IgG titers against P. gingivalis may be associated with the progression of periodontitis.

Follicular dendritic cell-secreted protein is decreased in experimental periodontitis concurrently with the increase of interleukin-17 expression and the Rankl/Opg mRNA ratio.

BACKGROUND AND OBJECTIVE: T-helper type 17 (Th17) cells produce interleukin-17 (IL-17) and help to protect against inflammation and infection in periodontal disease. Furthermore, while follicular dendritic cell-secreted protein (FDC-SP) may be involved in the inflammation of periodontal tissue, the biological role of FDP-SP in periodontal disease is still unknown. The purpose of the present study was to clarify the expression of IL-17 and FDC-SP in experimental periodontitis in rats. MATERIAL AND METHODS: Seven-week-old male Wistar rats were divided into baseline control, sham and test groups. Experimental periodontitis was induced by placing a ligature in the mesiopalatal area, and untreated rats served as a baseline control group. Morphological changes in alveolar bone were investigated 7, 14 and 28 d after treatment. Expression of the Rankl, osteoprotegerin (Opg) and Il17 genes was analyzed 5 and 7 d after the induction of experimental periodontitis. RESULTS: Alveolar bone resorption progressed in the test group for 7 d, but not thereafter. At 5 d after the induction of periodontitis, the Rankl/Opg mRNA ratio and the expression of IL-17 in the test group were significantly increased compared with the respective values in the baseline control group; however, there were no significant differences between the test and control groups at 7 d. The expression of FDC-SP was significantly decreased in the test group compared with the baseline control group at 5 and 7 d after the induction of periodontitis, and this value had returned to normal levels at 14 and 28 d. CONCLUSION: These results suggest that both IL-17 and FDC-SP could be involved in the inflammatory response, and FDC-SP in the junctional epithelium might play an important role in the Th17 cell-related immune response.

Geometric morphometric evaluations of a randomized prospective split-mouth study on modes of ligation and reverse-curve mechanics.

OBJECTIVES: To evaluate tooth position after six and 9 months of orthodontics with conventional brackets on one side of the dentition and ligature-less brackets on the other. SETTING AND SAMPLE POPULATION: Orthodontic Division, Vienna Medical University. Twenty patients aged 22.5 ± 5.7 years, symmetrical malocclusion and arch form, no premolar extraction. MATERIAL AND METHODS: Prospective split-mouth study, 0.022-inch SmartClip self-ligating brackets assigned randomly to the left or right dentition, conventional 0.018-inch brackets on the other side. 52 dental landmarks, digitized on plaster casts, represented dental arches at baseline (t0), 6 months and 9 months (t1, t2). During t0-t1, we used 0.016 and 0.014 x 0.025 inch superelastic wires, during t1-t2 connected reverse-curve hemiarch wires: 0.017 x 0.025 inch ß-titanium on the ligature-less side, and 0.016 x 0.022 inch Elgiloy multiloop wires on conventional brackets. Morphometric analyses were used to assess differences in dental arch shapes. RESULTS: Neither initial alignment nor the reverse-curve phase showed statistically significant differences between ligature-less and conventional brackets in moving teeth. CONCLUSION: Morphometric shape analyses corroborated current evidence that self-ligating brackets were no more effective than conventional brackets with steel ligatures after 6-month initial alignment. From months 6-9 treatment with ß-titanium reverse-curve wires on 0.022-inch ligature-less brackets resulted in similar tooth positions as accomplished by Elgiloy multiloop wires on 0.018-inch steel-ligature-tied brackets.

Antimicrobial photodynamic therapy using a diode laser with a potential new photosensitizer, indocyanine green-loaded nanospheres, may be effective for the clearance of Porphyromonas gingivalis.

BACKGROUND: Antimicrobial photodynamic therapy (aPDT) is a new treatment method for the removal of infectious pathogens using a photosensitizer and light of a specific wavelength, e.g., toluidine blue with a wavelength of about 600 nm. We explored a new photosensitizer and focused on indocyanine green (ICG), which has high absorption at a wavelength of 800-805 nm. We investigated the bactericidal effect of PDT on Porphyromonas gingivalis using a new photosensitizer, ICG-loaded nanospheres with an 805 nm wavelength low-level diode laser irradiation. METHODS: We designed ICG-loaded nanospheres coated with chitosan (ICG-Nano/c) as a photosensitizer. A solution containing Porphyromonas gingivalis (10(8)  CFU/mL) with or without ICG-Nano/c (or ICG) was prepared and irradiated with a diode laser or without laser irradiation as a negative control. The irradiation settings were 0.5 W with a duty ratio of 10%, for 3-100 ms in repeated pulse (RPT) or continuous wave mode. CFU were counted after 7 d of anaerobic culture. RESULTS: We observed that ICG-Nano/c could adhere to the surface of P. gingivalis. When ICG-Nano/c was used for aPDT, irradiation with RPT 100 ms mode gave the lowest increase in temperature. Laser irradiation with ICG-Nano/c significantly reduced the number of P. gingivalis (i.e., approximately 2-log10 bacterial killing). The greatest bactericidal effect was found in the RPT 100 ms group. However, laser irradiation (RPT 100 ms) with ICG, as well as without photosensitizer, had no effect on the number of bacteria. CONCLUSIONS: Within the limits of this study, ICG-Nano/c with low-level diode laser (0.5 W; 805 nm) irradiation showed an aPDT-like effect, which might be useful for a potential photodynamic periodontal therapy.

In vivo evaluation of a metronidazole-containing gel for the adjuvant treatment of chronic periodontitis: preliminary results.

The present study developed an experimental metronidazole-based gel and evaluated its efficacy for the adjuvant treatment of chronic periodontitis. Sixteen patients were randomly allocated into two groups of eight subjects according to the following proposed treatments: (1) scaling and root planing (active control) or (2) scaling and root planing and direct periodontal intrapocket application of 15% metronidazole-based gel in two sites (≥5 mm in depth) (experimental group). Potential changes in the subgingival microbiota were assessed using a DNA Checkerboard method at three proposed times: baseline and following 7 or 30 days of drug administration. High-performance liquid chromatography (HPLC) monitored metronidazole concentrations in the crevicular fluid during treatment. The metronidazole experimental group presented lower bacterial counts than the control group at the three evaluated times (p<0.01 for baseline, p<0.001 for 7 or 30 days) when the target species were analyzed as a pool of bacteria. Samples revealed significantly lower counts 7 days after drug administration compared with baseline or after 30 days (p<0.05). HPLC analysis detected gel 1 h after application. The metronidazole-based gel significantly decreased the total bacterial count at the three evaluated times. Periodontopathogenic species were not different after gel administration.

Cervical sympathectomy causes alveolar bone loss in an experimental rat model.

BACKGROUND AND OBJECTIVE: Periodontal disease, a pathological destructive inflammatory condition, is characterized by alveolar bone loss. Recent studies have suggested a correlation between the sympathetic nervous system and bone remodeling. To confirm the importance of the sympathetic nervous system in bone resorption, we investigated the effects of superior cervical ganglionectomy and oral challenge with Porphyromonas gingivalis on alveolar bone loss in rats. MATERIAL AND METHODS: Rats were divided into three groups: group A underwent a sham operation as the control group; group B underwent superior cervical ganglionectomy; and group C underwent a sham operation and oral challenge with P. gingivalis. Horizontal alveolar bone loss was evaluated by measuring the distance between the cemento-enamel junction and the alveolar bone crest. Cytokine gene expression in the gingival tissues was assessed using reverse transcription-polymerase chain reaction analyses. The furcation areas of the mandibular molars were examined histologically. RESULTS: Both superior cervical ganglionectomy and oral challenge with P. gingivalis resulted in accelerated alveolar bone loss. Gingival tissues in the superior cervical ganglionectomy group showed increased expression of the cytokines interleukin-1 alpha, tumor necrosis factor-alpha and interleukin-6. The density of neuropeptide Y-immunoreactive fibers was decreased following superior cervical ganglionectomy. Osteoclasts were observed in the superior cervical ganglionectomy and P. gingivalis-challenged groups. CONCLUSION: Both superior cervical ganglionectomy and oral challenge with P. gingivalis induced alveolar bone loss. These results provide new information on the occurrence of alveolar bone loss, in that both oral challenge with P. gingivalis and superior cervical ganglionectomy are important accelerating factors for alveolar bone loss. Thus, we suggest that the sympathetic nervous system is linked with the prevention of alveolar bone loss.

Dynorphin-A immunoreactive terminals on the neuronal somata of rat mesencephalic trigeminal nucleus.

Dynorphin-A-like immunoreactivity was investigated in the rat mesencephalic trigeminal nucleus (Mes 5) at the light and electron microscopic levels. Dynorphin-A immunoreactive fibers and puncta, likely representing nerve terminals, were observed throughout rostrocaudal extension of the Mes 5 at the light microscopic level. Within the rostrocaudal extension, more abundant fibers and puncta were localized in the midbrain-pontine junction and pontine areas than in the midbrain area. At the electron microscopic level, dynorphin-A immunoreactive synapses were observed on the somata of Mes 5. Dynorphin-A-like immunoreactivity tended to be restricted to dense-cored vesicles in the synapses. These results suggest that dynorphin-A-containing fiber systems affect mastication through the Mes 5.

Comparative analysis of putative periodontopathic bacteria by multiplex polymerase chain reaction.

BACKGROUND AND OBJECTIVE: The polymerase chain reaction (PCR) has been applied for the rapid and specific detection of periodontopathic bacteria in subgingival plaque and is potentially of clinical benefit in the diagnosis and treatment of periodontitis subjects. However, several technical points need to be modified before the conventional PCR detection system can be used by clinicians. MATERIAL AND METHODS: To develop a PCR-based technique more applicable for clinical use than conventional PCR, we established a multiplex PCR for five putative periodontopathic (Treponema denticola, Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Prevotella intermedia and Tannerella forsythia) and two nonperiodontopathic (Streptococcus sanguinis and Streptococcus salivarius) species of bacteria using whole-plaque suspension as templates, and detected bacteria in subgingival plaque taken from 85 subjects at the supportive periodontal therapy stage after active periodontal treatments. RESULTS: Among putative periodontopathic bacteria, the detection frequency of T. denticola and P. gingivalis was elevated in parallel with higher probing pocket depth and clinical attachment loss, and had 4.2-14.1 times increasing odds of the clinical parameters tested. Detection of any of the five species of putative periodontopathic bacteria markedly increased the odds ratio of a higher probing pocket depth, clinical attachment loss and bleeding on probing. CONCLUSION: The multiplex PCR system developed in this study enabled the detection of all the bacteria under investigation in one reaction tube in a less time- and labor-intensive manner than conventional PCR. These results support the potential clinical use of multiplex PCR for detecting periodontopathic bacteria and for evaluating therapeutic strategies and predicting the prognosis for each subject.

DNA Checkerboard method for bacterial detection of microbiota from teeth and tongue biofilms. A preliminary study.

AIM: The aim of this study was to determine the prevalence of 13 bacterial species in the dorsum tongue biofilm and compare its microbiota to that of subgingival samples in healthy adult subjects using DNA Checkerboard hybridization. METHODS: A total of 40 samples, from subgingival and tongue biofilm, were enrolled into the study. All the samples were harvested and analyzed by DNA Checkerboard method for their content of 13 species of bacteria. Bacterial scores from each subject and location were averaged and the results of both sites were compared using the Wilcoxon signed ranks test. RESULTS: All the microorganisms evaluated were detected in both tongue and subgingival samples, without significant differences in their prevalence. CONCLUSIONS: The dorsum of the tongue was colonized by various microorganisms with similar prevalence as found in the subgingival biofilm of healthy individuals, suggesting that the tongue could be a potential microbial reservoir and may play a role in the recolonization of teeth surfaces.

Stimulatory effects of induced phagocytosis on the function of isolated thyroid cells.

Stimulation of endocytosis is a very early effect of thyrotropin on thyroid. However, the relationship of the endocytotic process to the many other thyrotropin effects on thyroid is not clearly defined. Since phagocytosis in isolated thyroid cells is a presumed model for in vivo endocytosis of colloid, we induced phagocytosis in isolated thyroid cells by incubating them at 37 degrees C with 0.109-mu diameter polystyrene microbeads; phagocytosis was confirmed in each experiment by electron microscopy and/or spectrophotometric analysis of dioxane cell extracts. Cells incubated with 50-100-mu diameter polystyrene macrobeads (too large to ingest) served as controls. Microbead-induced phagocytosis in isolated thyroid cells was consistently accompanied by increases in: (a) cyclic 3',5'-adenosine monophosphate-(14)C formation from adenine-8-(14)C (66%); (b) iodide-(131)I trapping (40%); (c) protein and RNA synthesis (30%); (d) phospholipogenesis (50%); (e) alpha-aminoisobutyric acid-1-(14)C uptake (15%). 50- to 100-mu diameter polystyrene macrobeads did not influence cell function in any of these experiments. Aminotriazole, 5 x 10(-3) (M), a peroxidase inhibitor, blocked the stimulatory effect of microbead-induced phagocytosis on phospholipogenesis only. These studies indicate that in isolated thyroid cells the phagocytotic process, per se, may alter activity of the membrane-bound adenyl cyclase enzyme. The resultant increase in cyclic 3',5'-adenosine monophosphate may be a triggering mechanism for (some) subsequent metabolic changes occuring during phagocytosis. Since these changes mimic those induced by thyrotropin, it is suggested that a variety of thyrotropin effects on thyroid may be secondary to stimulation of colloid resorption and hormone secretion.

Antitumor effects of the MIG and IP-10 genes transferred with poly [D,L-2,4-diaminobutyric acid] on murine neuroblastoma.

The number of tumor-infiltrating lymphocytes is known to be related to outcomes in patients with a variety of malignancies. Interferon (IFN) gamma-inducible protein-10 (IP-10) and monokine induced by IFNgamma (MIG) have chemotactic effects on activated T lymphocytes and natural killer (NK) cells. The aim of this study was to evaluate the antitumor effects of exogenous expression of the MIG and IP-10 genes delivered to solid tumors by poly [D,L-2,4-diaminobutyric acid] (PDBA). The murine MIG and IP-10 genes were transfected into mouse neuroblastoma cells with PDBA. MIG and IP-10 levels in supernatants of transfected cells were measured by enzyme-linked immunosorbent assay. The chemotactic activities of MIG and IP-10 in the supernatants of cell cultures were measured by chemotaxis assay. Tumors were injected in vivo with PDBA/pmMIGColon, two colonsIP-10 complexes to evaluate the effects of these genes on tumor volume and survival time of mice. Transfected PDBA/pmMIGColon, two colonsIP-10 complexes produced MIG and IP-10 protein in vitro. MIG and IP-10 proteins secreted into the culture medium showed chemotactic activity. MIG and IP-10 gene therapy with the PDBA system in vivo significantly inhibited tumor growth and prolonged survival time of mice. In conclusion, PDBA-mediated MIG and IP-10 gene therapy may be useful for treatment of solid tumors.

Immobilization stress induces BDNF in rat submandibular glands.

Brain-derived neurotrophic factor (BDNF) promotes survival and differentiation of the cells of the central and peripheral nervous systems. BDNF has been identified in non-neural tissue, including the heart, lung, platelets, lymphocytes, and lacrimal glands. Immobilization stress modifies BDNF mRNA expression in some organs. The present study examines the effect of immobilization stress on BDNF, and its receptor TrkB, in male rat submandibular glands. Increased BDNF mRNA and protein expression were observed in duct cells as a result of immobilization stress, as demonstrated by real-time PCR, Western blot, immunohistochemistry, and analysis by microdissection. TrkB mRNA was not detected in salivary gland tissue, or oral or esophageal mucosa, by RT-PCR. Rat submandibular gland was thus identified as an organ which expresses BDNF. Furthermore, the results of this study suggest that increased salivary BDNF expression occurs following immobilization stress.

The efficiency of X-ray microanalysis in low-vacuum scanning electron microscope: deposition of calcium on the surface of implanted hydrogel intraocular lens (IOL).

To examine the calcification of implanted hydrogel IOL by X-ray microanalysis, we compared conventional transmission electron microscopy (TEM) with low-vacuum scanning electron microscopy (SEM). We also compared metal coating with non metal coating in low-vacuum SEM. Calcification of IOL showed deposits which were located in the superficial substance of lens. In conventional TEM and X-ray microanalysis, calcium, phosphate and silicon were detected in the deposits. In low-vacuum SEM, the deposits detected in metal coating were calcium, phosphorus, sodium and magnesium, but not silicon. However, in non metal coating, the deposits contained not only calcium, phosphorus, silicon, sodium and magnesium, but also fluoride, aluminum and argentums. It was concluded that in conventional TEM where a specimen is fixed and dehydrated in ethanol, various elements leak out. On the other hand, when a specimen is coated with carbon and gold palladium for SEM, light elements might not be detected in X-ray microanalysis. Low-vacuum SEM preparation does not need metal coating and low-vacuum SEM appears to provide a highly efficient method for X-ray microanalysis.

A factor in human saliva that induces differentiation of mouse myeloid leukemia cells.

The differentiated functions of phagocytosis, locomotion, and morphological changes into cells resembling granulocytes and macrophages were induced in cultured mouse myeloid leukemic cells, M1 clone 34, by treatment with human saliva. The rates of induction of these differentiated phenotypes were proportional to the concentration of saliva added and the period of treatment. The factor inducing differentiation was nondialyzable and heat labile. This factor was purified 70-fold by fractionation with Diaflo membranes and DE52 column chromatography. The activities inducing the three differentiated characters examined were purified together, suggesting that they were all due to the same factor.