[Clinicopathological study in 28 cases of oral basaloid squamous cell carcinomas].

OBJECTIVE: To investigate the clinicopathologic features and prognostic factors in oral basaloid squamous cell carcinoma. METHODS: Retrospective analysis of oral basaloid squamous cell carcinomas patients who underwent tumor resection during the period from January 2002 to December 2020 in the authors' hospital, especially the clinicopathologic characteristics of 28 cases with confirmed diagnosis and follow-up data. Immunohistochemistry was performed to define the helpful markers for differentiation diagnosis. The factors influencing the prognosis were evaluated based on Kaplan-Meier method. RESULTS: The tongue and mouth floor (11 cases, 39.3%) were the most frequently involved sites, followed by gingiva (6 cases, 21.4%), buccal (5 cases, 17.9%), palate (4 cases, 14.3%), and oropharynx (2 cases, 7.1%). The majority of basaloid squamous cell carcinomas were in advanced stage, with 12 cases in stage Ⅱ and 16 cases in stages Ⅲ-Ⅳ. Twelve of 28 patients were identified to have cervical lymph node metastasis, which was confirmed by histopathological examination. The incidence rate of lymph node metastasis was 42.9% (12/28). Nine tumors recurred, with one metastasized to the lung. At the meantime, the 28 conventional squamous cell carcinomas were matched with the same stage, among which 13 cases were identified with cervical lymph node metastasis. The incidence rate of lymph node metastasis was 46.4% (13/28). Five cases recurred, with two cases that metastasized to the lung and one to the brain. The 5-year overall survival rates of the basaloid squamous cell carcinoma and conventional squamous cell carcinoma patients were 54.6% and 53.8%, respectively. Histopathologically, basaloid cells consisted of tumor islands without evident keratinization but frequently with comedo-like necrosis within the tumor islands. CK5/6 and P63 exhibited strongly positive in all the 28 cases, whereas neuroendocrine markers, CgA and Syn, were negative. Eight cases positively expressed P16; one case showed focal SOX10 positive but CK7 negative. CONCLUSION: The majority of oral basaloid squamous cell carcinomas present in advanced stage with a high tendency to lymph node metastasis, but the overall survival rates are not significantly different from conventional squamous cell carcinomas matched with the same stage. The human papilloma virus (HPV), as HPV-positivity rate is high, correlates to good prognosis. In addition, CK7 & SOX10 immunohistochemistry could contribute to differential diagnosis for basaloid squamous cell carcinoma with solid adenoid cystic carcinoma.

[Analysis of non-bacterial respiratory pathogens in children in Ningbo City from 2019 to 2021].

Objective: To investigate the distribution characteristics of respiratory non-bacterial pathogens in children in Ningbo from 2019 to 2021. Methods: A retrospective analysis was performed on 23 733 children with respiratory tract infection who visited the department of pediatrics of Ningbo Women and Children's Hospital from July 2019 to December 2021. There were 13 509 males (56.92%) and 10 224 females (43.08%), with an age range of 1 day to 18 years old. There were 981 cases in the neonatal group (younger than 1 month old), 5 880 cases in the infant group (1 month to younger than 1 year old), 6 552 cases in the toddler group (1 to younger than 3 years old), 7 638 cases in the preschool group (3 to younger than 7 years old), and 2 682 cases in the school-age group (7 to 18 years old). Thirteen respiratory pathogens were detected by multiple polymerase chain reaction (PCR) based on capillary electrophoresis, and SPSS 23.0 software was used for statistical analysis of the results, the count data were expressed as percentages, and the χ2 test was used for comparison between groups. Results: Of the 23 733 specimens, 13 330 were positive for respiratory pathogens, with a total positive rate of 56.17%. The positive rates of human rhinovirus (HRV) 24.05% (5 707/23 733), human respiratory syncytial virus (HRSV) 10.45% (2 480/2 3733) and mycoplasma pneumoniae (Mp) 7.03% (1 668/23 733) were in the first three. The positive rates of pathogens in the male and female children were 57.47% (7 763/13 509) and 54.45% (5 567/10 224), respectively, and the difference was statistically significant (χ2=21.488, P<0.001). The positive rates in the neonatal group, infant group, toddler group, preschool group, and school-age group were 31.80% (312/981), 54.71% (3 217/5 880), 63.23% (4 143/6 552), 59.83% (4 570/7 638), 40.57% (1 088/2 682), respectively, and the difference among the groups was statistically significant (χ2=681.225, P<0.001). The single infection rate was 47.43% (11 256/23 733), the mixed infection rate of two or more pathogens was 8.74% (2 074/23 733), most of which were mixed infections of two pathogens. HRV, HADV, HCOV, Ch disseminated in the whole year. HRSV, HMPV, Boca, HPIV occurred mostly in fall and winter. The positive rates of FluA, FluB, Mp were at a low level after the corona virus disease 2019 (COVID-19) epidemic (2020 and 2021). The positive rates of FluA, H1N1, H3N2, FluB, HADV, Mp in 2020 were significantly lower than in 2019 (P<0.05). The positive rates of HPIV, HRV, HCOV, Ch in 2020 were significantly higher than in 2019 (P<0.05). The positive rates of FluA, H1N1, H3N2, HPIV, HCOV, Mp, Ch in 2021 were significantly lower than in 2020 (P<0.05). The positive rates of Boca, HMPV, HRSV in 2021 were significantly higher than in 2020 (P<0.05). Conclusion: From 2019 to 2021, the main non-bacterial respiratory pathogens of children in Ningbo City were Mp and HRV, and the detection rates of respiratory pathogens varied among different ages, seasons and genders.

[Cervical lymph node metastasis in adenoid cystic carcinoma of the salivary glands: A clinicopathologic study].

OBJECTIVE: To investigate the incidence and clinicopathologic features of cervical lymph node metastasis in salivary gland adenoid cystic carcinoma (AdCC). METHODS: Retrospective analysis was made in 798 AdCC patients who underwent tumor resection during January, 2001 to January, 2019 in Peking University School and Hospital of Stomatology, especially the clincopathologic characteristics of 82 cases with lymph node metastasis. RESULTS: In the study, 82 of the 798 patients were identified with cervical lymph node metastasis, which was confirmed by histopathological examination. The palate, the region of sublingual gland and mouth floor, and the parotid were the frequently involved primary sites for AdCCs. The general incidence rate of lymph node metastasis was approximately 10%. The submandibular gland, the region of sublingual gland and mouth floor, and the mobile tongue were the most frequent sites of lymph node metastasis with the incidence rates of 20.8%, 16.1%, and 15.1%, respectively; while lymph node metastasis was uncommon in the tumors which were the origin from the palate and parotid, with incidence rates of 6.1% and 3.4%, respectively. Most AdCC cases (70.7%) showed the classic "tunnel-style" metastatic pattern of occurrence, and the level I and II regions were the most frequently involved areas. The 5-year and 10-year overall survival rates of the patients with lymph node metastasis were 77.4% and 20.6% respectively, while the 5-year and 10-year overall survival rates of the patients with no lymph node metastasis were 83.5% and 57.6%, respectively. The univariate analysis demonstrated that statistically significant differences in the overall survival for the presence of lymph node metastasis (P<0.001). In the meantime, the 5-year disease-free survival rate of the patients with lymph node metastasis also showed statistically significant differences to that of the AdCC patients with no lymph node metastasis. In addition, the primary site and histological grade were significantly associated with lymph node metastasis, and the high-grade solid growth pattern was identified as a strong predictor for the occurrence of lymph node metastasis. CONCLUSION: Cervical lymph node metastasis has a high tendency of occurrence in submandibular gland and tongue-mouth floor complex, and the high-grade solid growth pattern could be taken as a strong predictor for the occurrence of lymph node metastasis, which correlates to poor prognosis of AdCC patients. A selective neck dissection should be considered as a management in such patients.

Lithium enhances alveolar bone formation during orthodontic retention in rats.

OBJECTIVE: To investigate the effect of lithium on alveolar bone formation during orthodontic retention in rats. MATERIALS AND METHODS: After 2 weeks of orthodontic tooth movement (OTM), 42 8-week-old male Wistar rats were randomly divided into two orthodontic retention groups: one without (control) and the other with LiCl treatment (LiCl group). Samples were collected on days 0, 3, 7 and 14 during the retention period. We evaluated the bone volume/total volume (BV/TV) ratio and new bone formation in the region of interests (ie, the root, the periodontal ligament and the adjacent alveolar bone around the distal buccal surface of the distal root of the maxillary first molar). We performed quantitative analyses, including histology, histomorphometry and immunohistochemistry to identify Runx2 and Osterix expression. RESULTS: The density of trabecular bone, the quantity of osteoblasts and the expression of osteogenic markers, Runx2 and Osterix, were significantly higher in the LiCl group than in the control group during the orthodontic retention period. CONCLUSION: LiCl enhances alveolar bone formation during orthodontic retention in rats.

[Risk analysis and preventive strategies of implant placement in patients with hypertension].

Recently, among the edentulous patients who undergo dental implants, the proportion of hypertensive patients remains high, which poses a greater challenge for clinicians to operate and to maintain the therapeutic effect. The present review comprehensively summarized clinical researches about the adverse effects on dental implants, outlined molecular mechanisms of the positive effects of various antihypertensive drugs on bone metabolism, and proposed that clinicians should select preventive strategies during preoperative and intraoperative procedures according to the blood pressure of patients with hypertension.

Virtual Reality for Hypertension in Tooth Extraction: A Randomized Trial.

Tooth extraction is one of the most common causes of dental anxiety and pain, leading to the elevation of blood pressure (BP) and heart rate (HR). Such effects may be exaggerated and cause life-threatening accidents in patients with hypertension. Therefore, the pain and anxiety management of these patients is imperative. Virtual reality (VR) has been demonstrated to be a distraction method to relieve anxiety and pain in clinical operations. Thus, we hypothesized that VR can control the elevation of BP and HR in patients with hypertension. In this study, 96 eligible patients with controlled hypertension who needed tooth extraction were randomized to the VR or standard care group by stratified randomization of anxiety grade and gender. Their BP and HR were dynamically monitored. The corresponding systolic and diastolic BP and HR values were selected when systolic BP was at the highest point of the process. BP was converted into mean arterial pressure (MAP) for comparison per the following formula: MAP = (systolic BP + 2 × diastolic BP)/3. Statistical analyses were by intention to treat and conducted in SPSS. Nonparametric rank sum tests were used to compare the difference of ΔMAP and ΔHR between the VR and standard care groups. Multivariate linear regression was applied to evaluate the effect of VR on ΔMAP and ΔHR. The results showed that the VR technique significantly decreased the elevation of MAP (P < 0.001) and HR (P < 0.001), and this effect was found even after adjusting for baseline characteristics and additional surgical procedures (ΔMAP, P < 0.001, R2 = 0.276; ΔHR, P < 0.001, R2 = 0.152). VR did not increase the incidence of adverse events (P = 0.677). In conclusion, the VR technique was effective in controlling BP and HR within an acceptable range and can help manage BP and HR during tooth extraction for patients with hypertension (Chinese Clinical Trial Registry: ChiCTR2100042132).

[Effects of different surface treatments on the bonding strength between the lithium disilicate glass ceramic and resin cements].

Objective: To investigate the effects of different surface treatments protocol on the bonding strength between lithium disilicate glass ceramic and resin cements. Methods: Ceramic specimens of 15 mm×13 mm×3 mm were used to evaluate the effects of different surface treatments of hydrofluoric acid etching and silane coupling in current research. Firstly, the standard lithium ceramic specimens were divided into 8 groups (n=16), and were etched by 4.5% hydrofluoric acid for 0, 10, 20, 30, 40, 60, 120 and180 s. Then specimens in each group was further divided into two sub-groups. In one sub-group specimens were coated with coupling agents and in the other were not. Shear bonding strength (SBS) and failure mode were tested and analyzed. The surface morphologies of hydrofluoric acid-etched ceramic specimens were observed by the scanning electron microscopy (SEM). Secondly, after being etched by 4.5% hydrofluoric acid for 30 s, the lithium ceramic specimens were coated with coupling agents at different temperatures: room temperature (12 ℃) for 60 s, 60 ℃ hot air for 60 s and 100 ℃ hot air for 60 s (n=8). SBS and fracture mode were tested and analyzed. The infrared spectrum analysis was used to characterize the coupled surfaces of the ceramic samples. Results: The maximum SBS values were obtained after the specimens were etched for 30 s. The silane coupled group showed a higher SBS value [(25.91±4.30) MPa, P<0.05] than the no-silane-coupled group [(20.27±4.92) MPa]. SBS decreased with extended etching time (>30 s) and the SEM photos showed over-etching morphologies. The 60 ℃ hot air treatment resulted in the maximum SBS value [(28.70±5.32) MPa] than that of the room temperature [(20.08±3.64) MPa] or 100 ℃ hot air [(25.64±4.86) MPa, P<0.05]. And the cohesive failure mode was found in 60 ℃ hot air treatment group. The infrared spectroscopy analysis showed the highest amount of silicon oxide bond in the 60 ℃ hot air treatment group. Conclusions: In this study, for this product, the optimum etching time of 4.5% hydrofluoric acid was 30 s. Furthermore, an ideal SBS value could be obtained when the silane coupling agents were applied additionally. SBS could be increased substantially when the 30 s-etched-ceramic product was coated with silane coupling agents at 60 ℃ hot air for 60 s.

The rag locus of Porphyromonas gingivalis might arise from Bacteroides via horizontal gene transfer.

Porphyromonas gingivalis is regarded as one of the risk factors of periodontitis. P. gingivalis exhibits a wide variety of genotypes. Many insertion sequences (ISs), located in their chromosomes, made P. gingivalis differentiate into virulent and avirulent strains. In this research, we investigated the prevalence of P. gingivalis in the gingival crevicular fluid (GCF) among periodontitis patients from Zhenjiang, China, detected the P. gingivalis rag locus distributions by multiplex polymerase chain reaction (PCR), and analyzed the origin of the P. gingivalis rag locus based on evolution. There were three rag locus variants co-existing in Zhenjiang. The results showed that the rag locus may be associated with severe periodontitis. This work also firstly ascertained that the rag locus might arise, in theory, from Bacteroides sp. via horizontal gene transfer.

[Mechanisms and regulations in tooth root development].

Tooth loss caused by trauma, periodontitis or inherited disorders severely affects human physical and mental health. As an essential part of the tooth, tooth root is connected to periodontal tissues to maintain the tooth in the alveolar socket. To figure out the molecular mechanisms regulating tooth root development will contribute to the discovery of new approaches in tooth root regeneration. The development of tooth root is a complicated process involving communication between the epithelial and mesenchymal tissues and the regulation of multiple signaling pathways. The present article reviewed the research progress of the signaling pathways in tooth root development.

Antiadipogenesis and Osseointegration of Strontium-Doped Implant Surfaces.

The decreased bone density and increased marrow adiposity that occur with aging may influence the outcome of dental implants. Strontium (Sr), an anabolic agent for the treatment of osteoporosis, has an inhibitory effect on adipogenesis but favors osteogenesis of bone marrow-derived mesenchymal stem cells (BMSCs). However, little is known about the effects and mechanisms of local Sr release on adipogenesis during bone formation in aged bone. In this study, a potential dental implant material, Sr-doped titanium, was developed via a sandblasted, large-grit, and acid-etched (SLA) method combined with a hydrothermal process. The effects of Sr-SLA on initial adhesion, proliferation, intracellular redox state, and adipogenic differentiation of senescent BMSCs were investigated. The in vitro results showed that Sr-SLA promoted spreading of senescent BMSCs via upregulation of the gene and protein expression of integrin ß1. In addition, it was revealed that Sr-SLA could reduce intracellular oxidative stress by decreasing the levels of reactive oxygen species and oxygen radicals and increasing the content of glutathione peroxidase. More important, Sr-SLA suppressed lipid droplet production and adipokines expression via downregulation of transcription peroxisome proliferator-activated receptor γ (PPARγ) and signal transducer and activator of transcription 1, thus inhibiting adipogenesis. Finally, the Sr-SLA implants were implanted in tibiae of aged (18-mo-old) Sprague-Dawley rats for 2 and 8 wk. Histomorphometric analysis demonstrated that Sr-SLA implants significantly enhanced osseointegration, and the inhibition effect on marrow adipose tissue formation was moderate. All these results suggest that due to the multiple functions produced by Sr, antiadipogenesis capability and rapid osseointegration were enhanced by the Sr-SLA coatings, which have potential application in dental implantation in the aged population.

[Clinical analysis of 555 outpatients with hand, foot and mouth diseases caused by different enteroviruses].

Objective: To study the clinical characteristics of outpatients with hand, foot and mouth disease (HFMD) caused by different serotypes of enteroviruses. Methods: This was a prospective study. From February 2017 to March 2018, 563 outpatients with HFMD were enrolled by systematic sampling in the Department of Infectious Diseases, Henan Children's Hospital. Throat swabs were collected to determine the serotypes via PCR. Demographic, clinical, and laboratory data were collected by standard questionnaire. All cases were followed up twice at 2 and 9 weeks after the initial outpatient visit through telephone interview. A total of 563 cases were enrolled and 555 (98.6%) cases were positive for human enteroviruses, including 338 (60.9%) males. Analyses were stratified by enterovirus serotypes, Chi square test or Fisher's exact test, Rank sum test was used for comparison among different groups. Results: The age of 555 cases was 24.2 (16.4, 41.3) months. Among them 44.0% (224 cases) were identified as coxsackievirus (CV)-A6, while 189 cases, 35 cases, 14 cases and 73 cases were identified as CV-A16, enterovirus (EV)-A71, CV-A10 and other serotypes, respectively. Fever (≥37.5 ℃) was present in 51.4% (285/555) of laboratory confirmed cases. The proportions of fever in cases of CV-A6 (68.9%(168/244)) and CV-A10 (12/14) were significantly higher than those in cases of CV-A16 (31.7%(60/189),χ(2)=57.344,14.313,both P=0.000), other serotypes (43.8%(32/73),χ(2)=15.101 and 8.242, P=0.000 and 0.004) and EV-A71 (37.1%(13/35), χ(2)=13.506 and 9.441, P=0.000 and 0.002) respectively. There was no significant difference between CV-A6 and CV-A10 in presentation of fever (χ(2)=1.785, P=0.182). There were 359 cases (64.7%) with eruptions in mouth, hands, feet and buttocks. Cases infected with EV-A71 had the highest proportions (74.3%(26/35)) of rash emerging simultaneously in mouth, hands, feet, and buttocks. The proportion in cases of CV-A16, CV-A6, CVA10 and other serotype were 73.5% (139/189), 61.9% (151/244), 7/14 and 49.3% (36/73), respectively. The proportion of rash on other parts of body, such as face, limbs or torso in cases infected with CV-A6 (16.8% (41/244)) was the higherest and the proportion in cases of CV-A16, EV-A71, CV-A10 or other serotypes were 8.5% (16/189) , 5.7% (2/35) , 1/14, 6.8% (5/73) , respectively. None of these cases developed serious complications. Desquamation occurred in 45.5% (179/393) cases 7.5 (5.0, 9.0) days after disease onset and 13.5% (53/393) cases showed onychomadesis 31.0 (18.0, 33.5) days after disease onset. The proportion of desquamation and onychomadesis associated with CV-A6 (64.2% (95/148) and 31.8% (47/148)) was significantly higher than CV-A16 (31.8% (49/154) and 1.3% (2/154), χ(2)=33.601 and 52.482, both P=0.000) and other serotypes (38.0%(19/50) and 6.0%(3/50),χ(2)=10.236 and 12.988, P=0.001 and 0.000). Desquamation appeared more in cases of CV-A6 than in cases of CV-A10 (2/11,χ(2)=9.386, P=0.002), with the proportion of onychomadesis higher in CV-A6 than in EV-A71 (3.3% (1/30),χ(2)=11.088, P=0.001). Conclusion: Clinical manifestation such as fever, rash emerging parts, desquamation and onychomadesis are different among outpatient HFMD cases infected with CV-A16, CV-A6, EV-A71, CV-A10 and other enteroviruses.

Comparison of toluidine blue-mediated photodynamic therapy and conventional scaling treatment for periodontitis in rats.

BACKGROUND AND OBJECTIVE: Periodontitis is a disease caused by bacterial infection accompanied with the inflammation of connected tissues and resorption of alveolar bone. The aim of this study was to investigate the in vivo photosensitization of periodontal bacteria in rats and to compare its efficacy with that of routine scaling and root planing. MATERIAL AND METHODS: Periodontitis was developed by submerging ligatures at the subgingival region of maxillary molars in 16 rats. Six weeks later, the infection sites were treated either with 1 mg/mL of toluidine blue plus 12 J/cm2 red laser irradiation, or by routine scaling and root planing. The therapeutic efficacy was assessed by evaluating the reduction of total bacterial flora and histological changes of periodontal tissues. RESULTS: Significant reduction of total bacterial flora was achieved by both photodynamic therapy and conventional therapy. The signs of inflammation that accompanied periodontitis, such as redness, increased plaque index and gingival index values, bleeding on probing and inflammatory cell infiltration, were greatly reduced without any obvious detectable injury to host tissues. Both photodynamic therapy and conventional therapy showed similar therapeutic results. CONCLUSION: Toluidine blue-mediated photodynamic therapy could effectively treat periodontitis in vivo and has high potential in clinical application.

Real-time detection of dental calculus by blue-LED-induced fluorescence spectroscopy.

Successful periodontal therapy requires sensitive techniques to discriminate dental calculus from healthy teeth. The aim of the present study was to develop a fluorescence-based procedure to enable real-time detection and quantification of dental calculus. Thirty human teeth--15 teeth with sub- and supragingival calculus and 15 healthy teeth--covered with a layer of physiological saline solution or blood were illuminated by a focused blue LED light source of 405 nm. Autofluorescence spectra recorded along a randomly selected line stretching over the crown-neck-root area of each tooth were utilized to evaluate a so called calculus parameter R, which was selected to define a relationship between the integrated intensities specific for healthy teeth and for calculus in the 477-497 nm (S(A)) and 628-685 nm (S(B)) wavelength regions, respectively. Statistical analysis was performed and a cut-off threshold of R=0.2 was found to distinguish dental calculus from healthy teeth with 100% sensitivity and specificity under various experimental conditions. The results of the spectral evaluation were confirmed by clinical and histological findings. Automated real-time detection and diagnostics for clinical use were implemented by a corresponding software program written in Visual Basic language. The method enables cost-effective and reliable calculus detection, and can be further developed for imaging applications.

[Complications analysis of adenoidectomy and tonsillectomy assisted with ablation on children].

Objective:To analyze the complications of adenotonsilectomy assisted with coblation in children. Method:Complications of 2 089 cases of children with adenoid and tonsil surgery assisted with coblation, in our hospital nearly 10 years, were analyzed by epidemiological methods through the method of retrospective analysis. Result:①the sex ratio of male to female was 2.08：1, average age (5.87±3.12) years old, and most of 2 089 cases 76.35% (1 595/2 089) were 3-7 years old; ②all cases underwent adenoidectomy. Different surgery methods of tonsil consisted of three groups as partial resection associated with ablation was 69.17% (1 445/2 089), ablation (channeling) alone was 22.26% (465/2 089) and total resection was 8.57% (179/208). The amount of bleeding in operation was (8.52±3.18)ml, average operation time was (30.15±8.26) minutes, the postoperative pain score was (3.77±1.61); ③The incidence of postoperative complications: postoperative bleeding (all were secondary bleeding cases) rate was 0.24% (5/2 089), recurrence rate was 0.14% (3/2 089), prevertebral lymphadenitis was 0.96% (20/2 089), the other was 0.29% (torus hyperplasia in 2 cases, dyspnea in 2 cases, 1 cases of angle of mouth burned, nasopharyngeal adhesion in 1 cases). Postoperative fever rate was 9.81% (205/2 089). Conclusion:coblation technique is a good method for the treatment of children's adenoids and tonsil diseases with high efficiency and low complications. But improving the operation procedure proficiency level and skills of operation is an important link to reduce complications.

Embolisation for life-threatening haemoptysis complicated by systemic artery-pulmonary circulation shunts.

SETTING: Tertiary referral centre. OBJECTIVE: To retrospectively observe the characteristics of bronchial angiograms in the setting of systemic artery-pulmonary circulation shunts (SPS), and to evaluate the safety and effectiveness of bronchial artery embolisation (BAE) for these patients with life-threatening haemoptysis. DESIGN: The records of life-threatening haemoptysis patients with SPS who presented to a tertiary referral centre from January 2009 to March 2014 were reviewed. RESULTS: SPS consisted of bronchial artery-pulmonary artery shunt (AAS) in 30 cases, bronchial artery-pulmonary vein shunt (AVS) in 4 cases, non-bronchial systemic artery-pulmonary circulation shunt (n-BPS) in 7 cases and more than one type of SPS in 4 cases (AAS and AVS in 3 cases, three types of SPS in 1 case). BAE using polyvinyl alcohol (PVA) was successful in 97.8% (44/45) of the patients. Cumulative rates of freedom from recurrence at 1 month, 1 year and 2 years were respectively 97.8%, 93.2% and 85.4%. No major procedure-related complications occurred. No significant differences were found in recurrence rates or cumulative haemoptysis control rates among patients with different types of SPS complications (P = 0.55 and 0.46, respectively). CONCLUSION: BAE with PVA was safe and effective for life-threatening haemoptysis complicated by SPS.

Diacylglycerol partitioning and mixing in detergent micelles: relevance to enzyme kinetics.

For many of the enzymes that utilize or produce diacylglycerols, detergent mixed micelles are often used in assay systems to solubilize the lipophilic substrates or products. The assumption is often made that the diacylglycerol (DAG) is solubilized and well mixed throughout the population of micelles during the time course of the assay. In the present work the partitioning and exchange dynamics of diacylglycerols (from dihexanoyl-DAG to didecanoyl-DAG) in a variety of detergent micelles have been studied by NMR and fluorescence methods. In all detergents, the longer the DAG chain lengths, the more detergent is required for solubilization. However, efficiency of solubilization varies tremendously with Triton X-100 the most efficient (i.e. the least detergent is required), and deoxycholate the least efficient in solubilizing DAG. The mixing and exchange dynamics of pyrene-labeled DAG molecules in these micelles (measured by stopped-flow fluorescence) were fastest for Triton X-100 and slowest with charged bile salt micelles. Of the detergent systems characterized, Triton X-100 appears to be the optimal detergent for use in assays of enzymes that interact with DAG (beta-octylglucoside and diheptanoylphosphatidylcholine have good exchange dynamics, but higher amounts of these detergents are needed to solubilize DAG). Bile salt micelles provide the least solubilization and the slowest exchange kinetics (so slow that this could be a significant problem in some enzyme assays). This information on DAG behavior in micelles is discussed with respect to assays of an enzyme that generates DAG as product (phospholipase C) and one that uses DAG as substrate (DAG kinase). Although slow exchange of DAG occurs in some micelle systems, this does not appear to be a rate-limiting step in the kinetics for either of these enzymes.

Effects of isoproterenol and forskolin on carbachol- and fluoroaluminate-induced polyphosphoinositide hydrolysis, inositol trisphosphate production, and contraction in bovine iris sphincter smooth muscle: interaction between cAMP and IP3 second messenger systems.

We have investigated the effects of isoproterenol (ISO) and forskolin on carbachol(CCh)- and fluoroaluminate (AlF4-)-induced phosphatidylinositol 4,5-bisphosphate (PIP2) hydrolysis, myo-inositol 1,4,5-trisphosphate (IP3) production, 1,2-diacylglycerol, measured as phosphatidic acid (PA) formation, and contraction in the bovine iris sphincter smooth muscle. The data from these studies can be summarized as follows. (1) CCh (20 microM) stimulated significantly PIP2 hydrolysis, IP3 production, PA formation, and contraction. (2) Addition of ISO (0.1-25 microM), which raises the tissue cAMP level, to muscle precontracted with CCh attenuated PIP2 hydrolysis, IP3 production, PA formation and contraction in a time- and dose-dependent manner. (3) AlF4- (10 microM) induced a slow but progressive hydrolysis of PIP2, accompanied by parallel production of IP3, formation of PA, and contraction of the smooth muscle. The effects of AlF4- were dose-dependent and inhibited by deferoxamine, an Al3+ ion chelator. (4) Both forskolin (1-25 microM), which directly stimulates adenylate cyclase, and ISO inhibited the responses induced by AlF4- (10 microM) in a dose-dependent manner. (5) NaF (1-5 mM) had no effect on the activity of phospholipase C (PLC), purified from bovine iris sphincter. Furthermore, phosphorylation of the enzyme by catalytic subunit of protein kinase A had no inhibitory effect on PLC activity against PIP2. In conclusion, neither the muscarinic receptor nor PLC are the target sites for cAMP inhibition; instead the putative G-protein, which couples the activated muscarinic receptor to PLC, may be phosphorylated by cAMP-dependent protein kinase. This could attenuate the stimulation of PLC by the G-protein, thus resulting in inhibition of PIP2 hydrolysis and consequently leading to muscle relaxation. These results demonstrate cross-talk between the cAMP and IP3-Ca2+ second messenger systems and suggest that this could constitute a regulatory mechanism for the process of contraction-relaxation in smooth muscle.

Molecular cloning of ERp29, a novel and widely expressed resident of the endoplasmic reticulum.

We have isolated a full-length cDNA clone for a novel 29 kDa protein that is highly expressed in rat enamel cells. The clone encodes a 259-residue protein, here named ERp29, with structural features (signal peptide and a variant endoplasmic reticulum-retention motif, KEEL) that indicate it is a reticuloplasmin. ERp29 has limited homology with protein disulfide isomerase and its cognates, but lacks their characteristic thioredoxin-like catalytic moiety and calcium-binding motifs. ERp29 mRNA was expressed in all rat tissues tested, and a homologous transcript was detected in other animal livers (primate, ruminant, marsupial). In human hepatoma cells, ERp29 mRNA expression was not increased by stresses (tunicamycin, calcium ionophore) that induced other reticuloplasmins. We conclude that ERp29 is a new, highly conserved member of the reticuloplasmin family which is widely expressed. The apparent lack of both calcium binding properties and stress responsiveness distinguish ERp29 from all major reticuloplasmins characterised to dates.

Blood-compatibility of polyurethane/liquid crystal composite membranes.

Polyurethane/liquid crystal composite membranes were first suggested to be used as biomaterials. In our work, three series of polyurethane/liquid crystal composite membranes based on three different kinds of liquid crystal compounds [N-(-4-methyoxybenzylidene)-4'-heptylaniline, 4-pentyl-4'-nitrile-biphenyl and cholesteryl oleyl carbonate] were prepared by casting on glass plates from a tetrahydrofuran (THF) solution of polymer and liquid crystal at room temperature. In our opinion, the formation of liquid crystal phase on the composite membrane surface is the basic requirement for getting better biomaterial. The result of this work is in accordance with our opinion. The effect of liquid crystal content on the formation of liquid crystal phase was identified by the observation of optical polarization microscopy (OPM). The results showed that the content of liquid crystal in composite membrane must be more than 30% (wt) in order to form liquid crystal phase on the composite membrane surface. The blood-compatibility of the composite membranes was assessed from SEM observation of the platelet's adhesion to membrane's surface, blood clotting time and haemolysis ratio. The observation of platelet's adhesion showed that the platelets gathered together on the pure polyurethane films, but the amount of platelets which were adherent on the surface covered by the liquid crystal phase was fewer than that of pure polyurethane film when platelet-rich plasma was allowed to be in contact with the membranes for 1 h at room temperature. The determination of blood clotting time and haemolysis ratio showed that these polyurethane/liquid crystal composite membranes, in which the content of liquid crystal was more than 30% (wt), appear to be beneficial in improving the blood compatibility and reducing the thrombogenicity.

Preparation and blood compatibility of polysiloxane/liquid-crystal composite membranes.

Polysiloxane/liquid crystal composite membrane was first suggested to be used as biomaterials. In this work, the polydimethyl-methylhydrosiloxane and polydimethyl-methylethylenesilosiane, as a substrate, were blended with cholesteryl oleyl carbonate (COC) in tetrahydrofuran, and then crosslinked into membranes on glass plates by means of the platinum catalyst at 110 degrees C for 20 min. The effects of the liquid-crystal content in composite membranes on the formation of liquid-crystal phase were verified by the observation of optical polarization microscopy. The relationship between the morphology of the composite membranes and blood compatibility was identified by the dynamic blood-clotting tests, haemolysis ratio measurement, platelet adhesion and SEM observation. The results show that the blood-compatibility of composite membranes with the concentration of liquid crystal 20, 30% (wt) is more excellent than that of other composite membranes.