[Associations between serum GDF15 and glycolipid metabolism disorder in metabolic associated fatty liver patients]

Objective: To investigate relationships between serum growth differentiation factor 15 (GDF15) and glycolipid metabolism in patients with metabolic associated fatty liver disease (MAFLD). Methods: The current investigation was a cross-sectional study. A total of 333 patients from the Fengxian District Central Hospital were recruited into the study after physical examination from February 2020 to February 2021. There were 107 patients with MAFLD and type 2 diabetes mellitus (T2DM), including 54 males and 53 females with a mean age of (57±11) years. There were 65 patients with simple MAFLD only, including 32 men and 33 women with a mean age of (49±5) years. There were 105 patients with T2DM only, including 53 men and 52 women, with a mean age of (56±10) years. A control group of 56 people without MAFLD or diabetes,28 male, 28 female, mean age (48±6) years, was also included in the study. Serum GDF15 was measured via enzyme-linked immunosorbent assays. IBM SPSS 26.0 was used for statistical analysis. Logistic regression was used to evaluate relationships between GDF15 and metabolic abnormalities in MAFLD patients. Results: GDF15 progressively increased in the control [385 (296, 484) ng/L], nonobese MAFLD [388 (319, 435) ng/L], obese MAFLD [426 (354, 527) ng/L], T2DM [664 (483, 900) ng/L], and MAFLD+T2DM groups [770 (560, 1 074) ng/L](H=113.82, P=0.001). There was no significant difference in serum GDF15 between the simple MAFLD [406 (339, 524) ng/L] and control group (U=1 505.50, P=0.132). GDF15 was significantly higher in the MAFLD+T2DM group than in the T2DM-only group (U=4 573.50, P=0.019). In logistic regression analysis increased GDF15 was associated with increased risks of simple MAFLD [odds ratio (OR)=2.202], T2DM (OR=29.656), and MAFLD+T2DM(OR=58.197). In patients with MAFLD, serum GDF15 was higher in the FIB4 index>1.45 group [773 (534, 1 162) ng/L] than in the FIB4 index<1.45 group [527 (389, 787) ng/L] (U=1 709.50, P<0.001). Increased GDF15 was associated with an increased risk of advanced liver fibrosis (OR=2.388). Conclusion: In patients with simple MAFLD, GDF15 level was not significantly higher than in the control group. In the T2DM-only group and the MAFLD+T2DM group GDF15 was significantly higher than in the control group. Increased serum GDF15 was associated with increased risk and severity of MAFLD complicated with abnormal glucose and lipid metabolism. High GDF15 increased the risk of advanced fibrosis in MAFLD patients.

[Response characteristics of tislelizumab combined with chemotherapy in first-line treatment of locally advanced or metastatic non-squamous non-small cell lung cancer]

Objective: To investigate the response characteristics of patients with locally advanced/metastatic non-squamous non-small cell lung cancer (nsq-NSCLC) treated with tislelizumab in combination with chemotherapy in the first line. Methods: Patients with nsq-NSCLC who achieved complete or partial remission after treatment with tislelizumab in combination with chemotherapy or chemotherapy alone in the RATIONALE 304 study, as assessed by an independent review board, were selected to analyze the response characteristics and safety profile of the responders. Time to response (TTR) was defined as the time from randomization to the achievement of first objective response. Depth of response (DpR) was defined as the maximum percentage of tumor shrinkage compared with the sum of the baseline target lesion length diameters. Results: As of January 23, 2020, 128 patients treated with tislelizumab in combination with chemotherapy achieved objective tumor response (responders), representing 57.4%(128/223) of the intention-to-treat population, with a TTR of 5.1 to 33.3 weeks and a median TTR of 7.9 weeks. Of the responders (128), 50.8%(65) achieved first remission at the first efficacy assessment (week 6), 31.3%(40) at the second efficacy assessment (week 12), and 18.0%(23) at the third and subsequent tumor assessments. The percentages of responders who achieved a depth of tumor response of 30% to <50%, 50% to <70% and 70% to 100% were 45.3%(58/128), 28.1%(36/128) and 26.6%(34/128), respectively, with median progression-free survival (PFS) of 9.0 months (95% CI: 7.7 to 9.9 months), 11.5 months (95% CI: 7.7 months to not reached) and not reached (95% CI: 11.8 months to not estimable), respectively. Tislelizumab plus chemotherapy were generally well tolerated in responders with similar safety profile to the overall safety population. Conclusion: Among responders to tislelizumab in combination with chemotherapy for nsq-NSCLC, 82.0%(105/128) achieves response within the first two tumor assessments (12 weeks) and 18.0%(23/128) achieves response at later (18 to 33 weeks) assessments, and there is a trend toward prolonged PFS in responders with deeper tumor response.

[Clinical efficacy analysis of functional rhinoplasty assisted by nasal endoscopy]

Objective: To analyse the clinical effect of endoscopy-assisted functional rhinoplasty. Methods: Twenty-one patients with congenital or traumatic deviated nose with nasal obstruction admitted to Qilu Hospital (Qingdao) from January 2018 to December 2021, including 8 males and 13 females, aged 22 to 46 years, were retrospectively analysed. Endoscopy-assisted functional rhinoplasty was performed in all patients. Deviated nasal septum was corrected, nasal septum cartilage graft was prepared through open approach assisted by endoscopy, the nasal frame structure was adjusted with the endoscopy-assisted rhinoplasty combined with middle and inferior turbinoplasty, and the patient's nasal ventilation function and external nose cosmetology were restored. Visual Analogue Scale (VAS), Nasal Obstruction Symptom Evaluation (NOSE), nasal acoustic reflex and nasal resistance were examined preoperatively and 6 months postoperatively. The minimum cross-sectional area of the first two nasal cavities (MCA) MCA1 and MCA2 and their distance between nostrils to the minimum cross-sectional area (MD) MD1 and MD2 were recorded, and the ratio of both sides (expressed in a/b) was calculated. The nasal volume of 5 cm depth from nostril (NV5) and nasal resistance total (RT) were recorded to evaluate the nasal ventilation function to analyse the clinical effect of functional rhinoplasty assisted by nasal endoscope. SPSS 25.0 software was used for statistical analysis. Results: At 6 months after the operation, for nasal ventilation evaluation, the VAS and NOSE scores of nasal obstruction decreased significantly than those before the operation ((1.81±0.81) points vs (6.71±1.38) points, (4.19±2.06) points vs (12.05±2.67) points, all P<0.05). In the objective indexes, MCA1, MCA2 and NV5 were significantly increased whereas RT, MCA1a/MCA1b, MCA2a/MCA2b, MD1a/MD1b and MD2a/MD2b were significantly decreased compared with those before the operation (all P<0.05). The MD1 and MD2 levels before and after operation had no significant differences (all P>0.05). In the evaluation of external nose morphology, postoperative ROE was significantly increased, and the deviation value of nasal appearance was significantly decreased ((16.19±2.56) points vs (10.24±3.24) points, (1.55±1.16) mm vs (5.63±2.41) mm, all P<0.05). In terms of postoperative patient satisfaction, 19 cases (90.5%) were very satisfied with nasal ventilation function, 2 cases (9.5%) were satisfied with nasal ventilation function; 15 cases (71.4%) were very satisfied with nasal appearance, and 6 cases (28.6%) were satisfied with nasal appearance. Conclusions: Nasal endoscopy-assisted functional rhinoplasty can improve the nasal ventilation function and external nasal morphology at the same time, with good clinical effect and high patient satisfaction.

[Analysis of the feasibility and prognostic value of circulating tumor DNA in detecting gene mutations in small cell lung cancer]

Objective: To investigate the feasibility of circulating tumor DNA (ctDNA) in detecting small cell lung cancer (SCLC) gene mutations and its prognostic value in chemotherapy and/or radiotherapy for SCLC patients. Methods: A total of 77 SCLC patients who were admitted to the Department of Thoracic Medical Oncology and the Department of Thoracic Radiation Oncology of Zhejiang Cancer Hospital from July 2016 to November 2019 were included. There were 66 males and 11 females, with a median age of 60 years. Among them, 42 cases were in limited stage (LS) and 35 cases were in extensive stage (ES). Next-generation sequencing (NGS) of patients' plasma ctDNA was performed before treatment. The differences of mutated genes and signaling pathways between LS and ES patients were analyzed and compared. Blood-based tumor mutation burden (bTMB) was calculated according to detected somatic cell mutations. Patients were divided into the high bTMB and the low bTMB groups according to the optimal threshold calculated by R software. Log-rank tests were used to compare progression-free survival (PFS) between the high bTMB and the low bTMB groups. Results: Among the 77 patients, 76 patients had gene mutations detected in their plasma, and the positive rate of ctDNA test was 98%. Among the 76 patients, the genes with the highest mutation frequency were TP53 (89%), RB1 (70%), LRP1B (34%), CREBBP (21%), MLL3 (21%), MLL2 (16%), NOTCH1 (13%), ROS1 (13%), BRCA2 (12%), and PTPRD (12%). The most common mutated genes in LS patients were TP53 (90%), RB1 (68%), LRP1B (24%), MLL2 (22%), and BRCA2 (17%); the most common mutated genes in ES patients were TP53 (89%), RB1 (71%), LRP1B (46%), CREBBP (31%), and MLL3 (29%). The mutation rates of NOTCH1 and CREBBP genes were significantly higher in ES patients (31.4% and 22.9%) than those in LS patients (11.9% and 4.8%) (both P<0.05). Signaling pathway analysis showed that there were more NOTCH pathway gene variations in ES patients. Among LS patients, patients in the high bTMB group (≥ 6.96 mutations/Mb) had a longer PFS than that in the low bTMB group (<6.96 mutations/Mb) (P=0.033); but no such difference was noted in ES patients. Conclusion: Plasma ctDNA sequencing detected SCLC gene mutation profiles similar to those reported in previous literature, thus ctDNA could be used as a tool to study SCLC genomics; the mutation spectra of ES-SCLC and LS-SCLC were different. bTMB has potential prognostic value in LS-SCLCs treated with chemoradiotherapy.

[Prognostic value of myocardial injury in patients with COVID-19]

Objective: To analyze the prognostic value of myocardial injury in patients with COVID-19. Method: Confirmed cases of COVID-19 patients admitted from January 31st to February 5th at isolation ward of Renmin Hospital of Wuhan University were divided into non-survival group and survival group according to the clinical outcomes 5 weeks after admission. Data including demographics, comorbidities, vital signs, laboratory results were obtained. Cardiac injury was defined as serum concentration of high sensitivity cardiac troponin I (hs-cTnI) above 0.04 μg/L. Univariate and multivariate Cox regression were used to analyze the prognostic value of myocardial injury in patients with COVID-19. Kaplan-Meier analysis was used to plotted survival curve and analyze the impact of myocardial injury on the survival outcome of COVID-19 patients. Results: A total of 202 patients were included, the age was 63 (51, 70) years old, 88 (43.6%) of them were male, 85 (42.1%) of them had comorbidities, 125 (61.9%) of them were severely to critically ill. Till March 11, 33 patients died, all of them were critically ill patients. The age, proportion of males, comorbidities, respire rate, serum levels of hs-cTnI and incidence of heart failure in the non-survival group were significantly higher than those in the survival group (all P<0.05). The hospitalization time of non-survival group was significantly shorter than that of survival group (6(4, 9) vs. 32(23, 36), P<0.001). Myocardial injury was an important prognostic factor of COVID-19 (HR=5.382, 95%CI 2.404-12.05, P<0.001). Kaplan-Meier survival analysis showed that the presence of myocardial injury was significantly associated with the reduced survival rate among COVID-19 patients (P<0.001). Conclusion: Myocardial injury is an important prognostic factor of COVID-19, COVID-19 patients with myocardial injury face a significantly higher risk of death.

[Study on the correlation between meteorological factors and acute otitis media in outpatients of children in Beijing]

Objective: To explore the characteristics of acute otitis media(AOM) in children in Beijing and its correlation with meteorological factors. Methods: Data were collected in 2011-2013 in the Otolaryngology Department of Capital Institute of Pediatrics. AOM in children with relevant information, such as age, sex and season, with the same period of the Beijing municipal meteorological data (the average temperature, average pressure, average wind speed, humidity and PM2.5) were compared to analysis the relationship of meteorological environmental parameters and the onset of AOM in children. Results: Annual morbidity of AOM was 7 589, 8 245, 7 242 respectively, no obvious difference(P=0.761). It was noted that one peak could be seen in December, and a valley in February, followed by August. Summer was less than the other three seasons (P<0.05). The morbidity of AOM had a small peak within one year after birth, then reached peak at the age of about 4, and then reduced gradually. In different age groups, male patients were higher than those of female. The incidence of AOM was positively correlation tendency with air pressure and PM2.5 (r=0.333, 0.093, P=0.000, 0.002), which was negatively correlation tendency with daily temperature or humidity (r=-0.327, -0.195, P=0.000, 0.000). Conclusions: The incidence of AOM of children in Beijing changes with age, and has obvious seasonal variation. There may be some correlation between the meteorological factors and the incidence of AOM in children.

[Surgical treatment of external auricular cholesteatoma involving tympanum and papilloma]

Objective:To explore the operation treatments and their outcomes of external auditory canal cholesteatomas involving the tympanic cavity and mastoid process. Method:Forty-two patients (45 ears) with external auditory canal cholesteatomas were included in this study who were operated. All lesions invaded the tympanic cavity and mastoid process. Excision of cholesteatoma, external auditory canal angioplasty and concha formation were performed. Ossicular chain reconstruction was performed in 3 ears. Mastoidectomy with close technique were performed in 4 ears. Open radical mastoidectomy was performed in 5 ears. Posterior bone-wall of auricular meatus reconstruction was performed in 3 ears. Tympanoplasty was performed in 21 ears. Pure tone audiogram and aural endoscope were carried out after the operation (3 months, 6months, 1 year, 2 years, 3 years…). Result:Stricture of external auditory meatus were occured in 2 ears in 2 and 3 months after surgery respectively. Cholesteatoma recurrence was observed in 2 ears in 1 year after operation. Wet ear was observed in 1 patient and then another operation was performed after 7 months. Besides the patients above, the epitheliums of the cavity were well in all other patients with complete tympanic membranes. Hearing was improved in all patients (hearing by air conduction:5－30 dB HL). Conclusion:According to the range of the external auditory canal cholesteatoma, we took different operation methods including tympanoplasty, open or close radical mastoidectomy and reconstruction of posterior wall of external auditory canal etc. Those methods, including external auditory canal angioplasty, cavity plasty of concha and skin grafting of external auditory canal, could help to prevent scar formation and stricture of external auditory canal, prevent cholesteatoma recurrence and improve hearing.

Analysis of allopolyploidy-induced rapid genetic and epigenetic changes and their relationship in wheat

We used the conventional and methylation-sensitive randomly amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) analyses to assess genome-wide changes and explore the relationships between genetic and epigenetic variations among individuals of a newly synthesized allohexaploid wheat line whose genomic constitution is identical to that of the natural common wheat, compared with its parent plants and a natural counterpart named Chinese Spring. We found rapid, extensive, and predominantly consistent non-Mendelian changes in the form of genetic and DNA methylation variations in the allohexaploid individuals. Specifically, at least 30-40% of the epigenetic component was truly independent of genetic changes, which answered a critical question, i.e. its autonomy in relation to the genetic context. Striking correlations were detected between genetic and epigenetic changes. Interestingly, as previously reported, the paternally donated nuclear genomes showed more genetic changes than the maternally donated ones; the loss of paternal bands was significantly correlated with the hypomethylation of CG or CHG sequences, suggesting an unknown link between genetic instability and hypomethylation. Sequence analysis indicated that most variations occurred in the cellular genes and sequences related to transposable elements. Based on these findings, the possible mechanisms and effects of the genomic changes in allopolyploid speciation and evolution were discussed.

Significant concentration changes of chemical components of PM1 in the Yangtze River Delta area of China and the implications for the formation mechanism of heavy haze-fog pollution

Since the winter season of 2013, a number of persistent haze-fog events have occurred in central-eastern China. Continuous measurements of the chemical and physical properties of PM1 at a regional background station in the Yangtze River Delta area of China from 16 Nov. to 18 Dec., 2013 revealed several haze-fog events, among which a heavy haze-fog event occurred between 6 Dec. and 8 Dec. The mean concentration of PM1 was 212μgm(-3) in the heavy haze-fog period, which was about 10 times higher than on clean days and featured a peak mass concentration that reached 298μgm(-3). Organics were the largest contributor to the dramatic rise of PM1 on heavy haze-fog days (average mass concentration of 86μgm(-3)), followed by nitrate (58μgm(-3)), sulfate (35μgm(-3)), ammonium (29μgm(-3)), and chloride (4.0μgm(-3)). Nitrate exhibited the largest increase (~20 factors), associated with a significant increase in NOx. This was mainly attributable to increased coal combustion emissions, relative to motor vehicle emissions, and was caused by short-distance pollutant transport within surrounding areas. Low-volatility oxidized organic aerosols (OA) (LV-OOA) and biomass-burning OA (BBOA) also increased sharply on heavy haze-fog days, exhibiting an enhanced oxidation capacity of the atmosphere and increased emissions from biomass burning. The strengthening of the oxidation capacity during the heavy pollution episode, along with lower solar radiation, was probably due to increased biomass burning, which were important precursors of O3. The prevailing meteorological conditions, including low wind and high relative humidity, and short distance transported gaseous and particulate matter surrounding of the sampling site, coincided with the increased pollutant concentrations mainly from biomass-burning mentioned above to cause the persistent haze-fog event in the YRD area.

Glyphosate biodegradation and potential soil bioremediation by Bacillus subtilis strain Bs-15

Glyphosate and glyphosate-containing herbicides have an adverse effect on mammals, humans, and soil microbial ecosystems. Therefore, it is important to develop methods for enhancing glyphosate degradation in soil through bioremediation. We investigated the potential of glyphosate degradation and bioremediation in soil by Bacillus subtilis Bs-15. Bs-15 grew well at high concentrations of glyphosate; the maximum concentration tolerated by Bs-15 reached 40,000 mg/L. The optimal conditions for bacterial growth and glyphosate degradation were less than 10,000 mg/L glyphosate, with a temperature of 35°C and a pH of 8.0. Optimal fermentation occurred at 180 rpm for 60 h with an inoculum ratio of 4%. Bs-15 degraded 17.65% (12 h) to 66.97% (96 h) of glyphosate in sterile soil and 19.01% (12 h) to 71.57% (96 h) in unsterilized soil. Using a BIOLOG ECO plate test, we observed no significant difference in average well color development values between the soil inoculated with Bs-15 and the control soil before 72 h, although there was a significant difference (P < 0.01) after 72 h. In the presence of Bs-15, the 5 functional diversity indices (Shannon index, Shannon uniformity, Simpson index, McIntosh index, and McIntosh uniformity) were greater (P < 0.01) compared with the control soil. These results indicate that Bs-15 could be used to alleviate contamination from glyphosate-containing herbicides, increasing the microbial functional diversity in glyphosate-contaminated soils and thus enhancing the bioremediation of glyphosate-contaminated soils.

Exploring laccase genes from plant pathogen genomes: a bioinformatic approach

To date, research on laccases has mostly been focused on plant and fungal laccases and their current use in biotechnological applications. In contrast, little is known about laccases from plant pathogens, although recent rapid progress in whole genome sequencing of an increasing number of organisms has facilitated their identification and ascertainment of their origins. In this study, a comparative analysis was performed to elucidate the distribution of laccases among bacteria, fungi, and oomycetes, and, through comparison of their amino acids, to determine the relationships between them. We retrieved the laccase genes for the 20 publicly available plant pathogen genomes. From these, 125 laccase genes were identified in total, including seven in bacterial genomes, 101 in fungal genomes, and 17 in oomycete genomes. Most of the predicted protein models of these genes shared typical fungal laccase characteristics, possessing four conserved domains with one cysteine and ten histidine residues at these domains. Phylogenetic analysis illustrated that laccases from bacteria and oomycetes were grouped into two distinct clades, whereas fungal laccases clustered in three main clades. These results provide the theoretical groundwork regarding the role of laccases in plant pathogens and might be used to guide future research into these enzymes.

Expression of claudin-1 and its relationship with lymphatic microvessel generation in hypopharyngeal squamous cell carcinoma

We investigated the relationship between claudin-1 and micro-lymphatic vessel density (MLVD) by detecting claudin-1 and protein D2-40 expression in cancer tissue specimens obtained from 97 patients with hypopharyngeal squamous cell carcinoma (HSCC). We also explored the correlation between the expression of these proteins and clinical tumor stage, pathological grading, and clinical prognosis in the patients. Moreover, we studied the mechanism of lymph node metastasis in HSCC, thereby providing information for treating HSCC and inhibiting lymph node metastasis. We detected levels of claudin-1 and protein D2-40 expression in cancer tissue from 97 patients with HSCC and para-tumor tissue from 90 patients by immunohistochemistry; we analyzed the correlation between markers and clinicopathological features by using the Pearson chi-square test and conducted survival analysis by the log-rank test. Claudin-1 expression was high in HSCC and was related to tumor differentiation and lymph node metastasis; Kaplan-Meier analysis showed that claudin-1 expression was related to patient survival rate (P = 0.012). There was a significant relationship between MLVD in the tissues adjacent to the carcinoma and the indices of histopathological grade, clinical stage, and lymph node metastasis. There was also a positive correlation between claudin-1 expression and MLVD. High expression of claudin-1 might induce the generation of tumor lymphatic vessels, which increases metastasis in the lymph node. Because claudin-1 is related to patient survival rate, it may be useful as a monitoring index for postoperative HSCC and might be a new target for treating the disease.

First Report of Streptomyces galilaeus Associated with Common Scab in China

During a survey of potato scab pathogens in China from 2003 to 2012, a new pathogen was found in Shanxi and Neimenggu provinces. The incidence was approximately 20% of all recovered strains. The lesions caused by the pathogen were slightly raised and similar to those caused by Streptomyces scabies (3). Lesions were excised (approximately 10 mm³) from 40 infected tubers, surface-disinfested with 0.3% NaOCl for 30 s, rinsed in sterile water three times, cut into 5 mm³, then sliced into 1-mm pieces, and plated on water agar amended with ampicillin (50 μg/ml). Plates were incubated at 28°C in the dark for 4 days. The spores of Streptomyces sp. strains growing from the tuber pieces were collected from single bacterial colonies and cultured on oatmeal agar. To fulfill Koch's postulates, one strain, CPS-2, was grown at 28°C for 10 days and the spores were washed from the plates as inoculum. One hundred milliliters of inoculum (1 × 10⁵ CFU/ml) was mixed with autoclaved soil and vermiculite (1:1) in each pot (15 cm in diameter). Cut tubers were planted in the pots (potato cv. Favorita, one plant per pot, five replicates) and grown under greenhouse conditions (22 ± 5°C). Typical common scab symptoms consisting of small, brown, raised lesions developed on potato tubers 12 weeks after planting. The same strain was re-isolated from the lesions of the new scabby tubers. Non-inoculated plants, treated as described above, but without strain CPS-2, remained healthy. The CPS-2 strain was identified based on morphological and physiological characterization and 16S rDNA sequence. On yeast-malt extract agar, the test strain produced grayish-white aerial hypha, reddish brown substrate mycelium and pigments, and loose spiral spore chains. Spores were smooth and were 0.8 to 0.9 × 1.1 to 1.2 μm in size (diameter and length). The ability of the strain to use single sources of carbon and nitrogen was verified according to the International Streptomyces project (4). The strain grew in media supplemented with L-arabinose, D-fructose, D-glucose, rhamnose, raffinose, meso-inositol, sucrose, and D-xylose, but not D-mannitol. It used L-hydroxyproline, L-methionine, and L-histidine, and produced melanin on tyrosine and peptone yeast extract agar. The strain did not grow at a pH less than 5.0 and was sensitive to streptomycin (20 μg/ml), phenol (0.1%), and crystal violet (0.5 μg/mL), but not to penicillin (10 IU/ml). The strain also produced hydrogen sulfide. The biological characteristics of strain CPS-2 were in accord with Streptomyces galilaeus. CPS-2 produced thaxtomin A in oatmeal liquid medium and the txt AB gene fragment was successfully amplified using specific primers (2). The 16S rDNA sequence of CPS-2 was amplified by PCR with primers 16S1-F: 5'-CATTCACGGAGAGTTTGATCC-3' and 16S1-R: 5'-AGAAAGGAGGTGATCCAGCC-3' (1) and sequenced. A BLAST search of the 16S rDNA sequence for CPS-2 was conducted using the NCBI GenBank database, resulting in 99.8% similarity to S. galilaeus (NR_040857). The 16S rDNA sequence for CPS-2 (1,388 bp) was deposited in GenBank (AY621378). To our knowledge, this is the first report of S. galilaeus causing common scab of potato in China. References: (1) R. A. Bukhalid et al. Appl. Environ. Microbiol. 68:738, 2002. (2) R. Flores-González et al. Plant Pathol. 57:162, 2008. (3) D. H. Lambert and R. Loria. Int. J. Syst. Bacteriol. 39:387, 1989. (4) E. B. Shirling and D. Gottlieb. Int. J. Syst. Bacteriol. 16:313, 1966.

Inheritance and fine mapping of a restorer-of-fertility (Rf) gene for the cytoplasmic male sterility in soybean

The cytoplasmic male sterility (CMS) line FuCMS5A and its restorer line FuHui9 were crossed to produce a segregating F(2) population for pollen fertility assay and the genetic mapping of restorer-of-fertility (Rf) gene. Results showed that the individual F(2) plants were fertile or semi-fertile based on their pollen fertility characteristics. The average ratios of viable pollen were 96.90% and 50.00% for each class of individuals. The segregation of F(2) plants showed a good fit to a 1:1 ratio, which reflects a typical heredity pattern of gametophytic CMS with fertility restorer being controlled by a single dominant gene. Using bulk segregation analysis (BSA) and genetic mapping, the Rf gene was mapped on molecular linkage group J (chromosome 16), between the simple sequence repeat (SSR) makers BARCSOYSSR-16-1064 and BARCSOYSSR-16-1082 with the distances of 0.59 and 0.83 cM, respectively. Four SSR markers (BARCSOYSSR-16-1070, Sctt011, BARCSOYSSR-16-1076 and BARCSOYSSR-16-1077) were cosegregating with this Rf gene in the mapping population. These makers will greatly facilitate the maker assisted selection procedures in CMS breeding programs and it lays a foundation for further map-base cloning of the Rf gene.

First Report of Potato Scab Caused by Streptomyces turgidiscabies in China

Potato scab, caused by several plant pathogenic Streptomyces species, is known to occur in potato-planting areas worldwide. Symptoms of disease on potato tubers are shallow, raised, or pitted corky lesions (2). In 1998, Streptomyces turgidiscabies was reported as a new potato scab pathogen from Hokkaido, Japan (3). Potato scab has been observed in many potato-cultivation areas in China and incidence of the disease was approximately 6 to 10% in some fields in 2006 (in our survey). To investigate the casual agent of scab disease, isolations were made from scabby potato tubers collected from different areas using oatmeal agar. Identification of an isolate from Shaanxi Province was based on morphological and physiological characterization followed by 16S rRNA confirmation. Characteristics were gray, aerial hypha, rectiflexuous spore chains, a smooth spore surface, and spores that were 0.5 to 0.7 × 1.0 to 1.2 μm. The strain did not produce melanin on tyrosine-peptone-yeast extract agar media, did not produce diffusible pigments, used all the International Streptomyces Project (ISP) sugars (4) as single carbon sources, used l-hydroxyproline, l-tyrosine, and l-histidine as single nitrogen sources but not l-methionine, grew at pH 4.5, was susceptible to streptomycin (20 μg ml^-1), phenol (0.1%), and penicillin (10 IU ml^-1) but not to crystal violet (0.5 μg ml^-1), and produced H₂S. The identification was confirmed by comparison of its 16S rRNA sequence with the GenBank database using the BLAST program. The 16S rRNA sequence was amplified by PCR with primers S1: 5'-CATTCACGGAGAGTTTGATCC-3' and S2: 5'-AGAAAGGAGGTGATCCAGCC-3' and sequenced. BLASTn analysis of the sequence obtained showed the highest similarity (99.9%) with S. turgidiscabies type strain ATCC 700248 (GenBank Accession No. AB026221). The sequence was submitted to GenBank (Accession No. AM889495). Pathogenicity of the strain was tested in the greenhouse on potato tubers of cv. Favorita grown in pots (one plant per pot, three replicates). One hundred milliliters of inoculum (1 × 10⁵ CFU ml^-1) of the strain was mixed with sterile soil and vermiculite (1:1) in each pot. Potato plants were grown at 25°C and the soil was allowed to dry between waterings. The immature potato tubers were used to evaluate scab symptoms 10 weeks after planting. All tubers inoculated with the pathogen developed typical common scab symptoms consisting of erumpent, brown, corky lesions, which is different from the symptoms caused by S. reticuliscabiei (1). The noninoculated control tubers did not show scab symptoms. S. turgidiscabies was reisolated from lesions of diseased immature tubers. The pathogenicity test indicates that S. turgidiscabies caused scab disease on potato tubers. To our knowledge, this is the first report of S. turgidiscabies causing potato scab disease in China. References: (1) K. Bouchek-Mechiche et al. Int. J. Syst. Evol. Microbiol. 56:2771, 2006. (2) R. Loria et al. Plant Dis. 81:836, 1997. (3) K. Miyajima et al. Int. J. Syst. Bacteriol. 48:495, 1998. (4) E. B. Shirling and D. Gottlieb. Int. J. Syst. Bacteriol. 16:313, 1966.

Platelet phospholipid n-3 PUFA negatively associated with plasma homocysteine in middle-aged and geriatric hyperlipaemia patients

Studies showed that increased dietary intake of n-3 polyunsaturated fatty acids (PUFA) has a cardiovascular beneficial effect. Increased plasma phospholipid (PL) docosahexaenoic acid (22:6n-3) is associated with decreased plasma homocysteine (Hcy). The aim of this study was to investigate the relationship between platelet PL fatty acid and plasma Hcy in middle-aged and geriatric hyperlipaemia patients (50 males, 31 females) and 65 healthy subjects (43 males, 22 females) in Hangzhou, China. Plasma Hcy demonstrated significant positive correlation with adrenic acid (22:4n-6) (r = 0.188, P = 0.018) and negative correlation with 22:6n-3 (r = -0.277, P = 0.001) and the ratio of n-3/n-6 (r = -0.231, P = 0.003) in sex-, age- and BMI-controlled partial correlation analysis. The present results suggest that increased ratio of n-3/n-6 PUFA in platelet PL is associated with decreased thrombotic risks such as plasma Hcy in middle-aged and geriatric hyperlipaemia patients in Hangzhou.

Ethylene induces antifreeze activity in winter rye leaves

Antifreeze activity is induced by cold temperatures in winter rye (Secale cereale) leaves. The activity arises from six antifreeze proteins that accumulate in the apoplast of winter rye leaves during cold acclimation. The individual antifreeze proteins are similar to pathogenesis-related proteins, including glucanases, chitinases, and thaumatin-like proteins. The objective of this study was to study the regulation of antifreeze activity in response to ethylene and salicyclic acid, which are known regulators of pathogenesis-related proteins induced by pathogens. Nonacclimated plants treated with salicylic acid accumulated apoplastic proteins with no antifreeze activity. In contrast, when nonacclimated plants were exposed to ethylene, both antifreeze activity and the concentration of apoplastic protein increased in rye leaves. Immunoblotting revealed that six of the seven accumulated apoplastic proteins consisted of two glucanases, two chitinases, and two thaumatin-like proteins. The ethylene-releasing agent ethephon and the ethylene precursor 1-aminocyclopropane-1-carboxylate also induced high levels of antifreeze activity at 20 degrees C, and this effect could be blocked by the ethylene inhibitor AgNO(3). When intact rye plants were exposed to 5 degrees C, endogenous ethylene production and antifreeze activity were detected within 12 and 48 h of exposure to cold, respectively. Rye plants exposed to drought produced both ethylene and antifreeze activity within 24 h. We conclude that ethylene is involved in regulating antifreeze activity in winter rye in response to cold and drought.

[Establishment of symbiotic system for Anoectochilus roxburghii (Wall.) Lindl. and endophytic fungi]

OBJECTIVE

Setting up a symbiotic system for Anoectochilus roxburghii and endophytic fungi, so as to study the relationship between them and try to set up new cultural methods for A. roxburghii.

METHOD

A. roxburghii and its endophytic fungi were cultured together on five kinds of media in flasks. The growth of the plantlets and fungi were observed. Symbiotic conditions were selected according to symbiotic characteristics.

RESULTS

A symbiotic system for A. roxburghii and endophytic fungi was set up. The optimum composition of the system induded NH4NO3 825 mg.L-1, KNO3 950 mg.L-1, MgSO4 185 mg.L-1, and inositol 100 mg.L-1, other organic components being 2/3 times those of MS medium, sugrose 15 g.L-1, and other components being the same as those of MS medium, agar 9 g.L-1, pH 5.8. The culture was effected at 24-25 degrees C under cool white fluorescent light (150 lx) for a photoperiod of 11 hours.

CONCLUSION

A. roxburghii and endophytic fungi can grow well together and form endomycorrhiza in the symbiotic system. Moreover, endophytic fungi help stimulate the growth and development of A. roxburghii.

Direct protein-protein coupling enables cross-talk between dopamine D5 and gamma-aminobutyric acid A receptors

GABA(A) (gamma-aminobutyric-acid A) and dopamine D1 and D5 receptors represent two structurally and functionally divergent families of neurotransmitter receptors. The former comprises a class of multi-subunit ligand-gated channels mediating fast interneuronal synaptic transmission, whereas the latter belongs to the seven-transmembrane-domain single-polypeptide receptor superfamily that exerts its biological effects, including the modulation of GABA(A) receptor function, through the activation of second-messenger signalling cascades by G proteins. Here we show that GABA(A)-ligand-gated channels complex selectively with D5 receptors through the direct binding of the D5 carboxy-terminal domain with the second intracellular loop of the GABA(A) gamma2(short) receptor subunit. This physical association enables mutually inhibitory functional interactions between these receptor systems. The data highlight a previously unknown signal transduction mechanism whereby subtype-selective G-protein-coupled receptors dynamically regulate synaptic strength independently of classically defined second-messenger systems, and provide a heuristic framework in which to view these receptor systems in the maintenance of psychomotor disease states.

Snow-mold-induced apoplastic proteins in winter rye leaves lack antifreeze activity

During cold acclimation, winter rye (Secale cereale L.) plants secrete antifreeze proteins that are similar to pathogenesis-related (PR) proteins. In this experiment, the secretion of PR proteins was induced at warm temperatures by infection with pink snow mold (Microdochium nivale), a pathogen of overwintering cereals. A comparison of cold-induced and pathogen-induced proteins showed that PR proteins accumulated in the leaf apoplast to a greater level in response to cold. The PR proteins induced by cold and by snow mold were similar when separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and examined by immunoblotting. Both groups of PR proteins contained glucanase-like, chitinase-like, and thaumatin-like proteins, and both groups exhibited similar levels of glucanase and chitinase activities. However, only the PR proteins induced by cold exhibited antifreeze activity. Our findings suggest that the cold-induced PR proteins may be isoforms that function as antifreeze proteins to modify the growth of ice during freezing while also providing resistance to the growth of low-temperature pathogens in advance of infection. Both functions of the cold-induced PR proteins may improve the survival of overwintering cereals.

Src, a molecular switch governing gain control of synaptic transmission mediated by N-methyl-D-aspartate receptors

The N-methyl-D-aspartate (NMDA) receptor is a principal subtype of glutamate receptor mediating fast excitatory transmission at synapses in the dorsal horn of the spinal cord and other regions of the central nervous system. NMDA receptors are crucial for the lasting enhancement of synaptic transmission that occurs both physiologically and in pathological conditions such as chronic pain. Over the past several years, evidence has accumulated indicating that the activity of NMDA receptors is regulated by the protein tyrosine kinase, Src. Recently it has been discovered that, by means of up-regulating NMDA receptor function, activation of Src mediates the induction of the lasting enhancement of excitatory transmission known as long-term potentiation in the CA1 region of the hippocampus. Also, Src has been found to amplify the up-regulation of NMDA receptor function that is produced by raising the intracellular concentration of sodium. Sodium concentration increases in neuronal dendrites during high levels of firing activity, which is precisely when Src becomes activated. Therefore, we propose that the boost in NMDA receptor function produced by the coincidence of activating Src and raising intracellular sodium may be important in physiological and pathophysiological enhancement of excitatory transmission in the dorsal horn of the spinal cord and elsewhere in the central nervous system.

Involvement of trigeminal subnucleus caudalis (medullary dorsal horn) in craniofacial nociceptive reflex activity

We have previously shown that an increase in electromyographic (EMG) activity of digastric (DIG) and masseter (MASS) muscles can be reflexly evoked by injection into the rat's temporomandibular joint (TMJ) region of the small-fibre excitant and inflammatory irritant mustard oil (MO). Since the trigeminal (V) subnucleus caudalis (Vc, i.e. medullary dorsal horn) has traditionally been viewed as an essential brainstem relay site of nociceptive information from craniofacial tissues, an EMG study was carried out in 45 anaesthetized rats to determine if Vc is involved in the MO-evoked increases in jaw muscle EMG activity. The effects of histologically confirmed surgical or chemical lesions of Vc on this evoked EMG activity were tested in different groups of rats. MO injection into the left TMJ region of intact rats evoked bilateral increases in EMG activity of DIG and MASS which could be significantly reduced by surgical transection of the left caudal brainstem at the obex level; MO injection into the right TMJ region in these same rats still readily evoked increases in EMG activity. A sagittal section medial to Vc or transection at the level of the second cervical spinal segment did not produce any significant reduction in the reflexly evoked EMG activity. Neurones in Vc, as opposed to fibres of passage, appear to be important for the MO-evoked EMG activity, since injection into Vc of the neurotoxic chemical ibotenic acid significantly reduced the mustard oil-evoked EMG activity. The Vc also appears to play a role in the activation of contralateral V motoneurons, as evidenced by the activation of the contralateral DIG and MASS muscles by the injection of MO into the left TMJ region of intact rats and by the reduction of this evoked EMG activity in the contralateral DIG and MASS of rats with a surgical transection or ibotenic acid lesion of the left Vc. These findings suggest that Vc may be a critical element in the neural pathways underlying the reflex responses evoked bilaterally in DIG and MASS muscles by noxious stimulation of the TMJ region.

Antifreeze proteins in winter rye leaves form oligomeric complexes

Antifreeze proteins (AFPs) similar to three pathogenesis-related proteins, a glucanase-like protein (GLP), a chitinase-like protein (CLP), and a thaumatin-like protein (TLP), accumulate during cold acclimation in winter rye (Secale cereale) leaves, where they are thought to modify the growth of intercellular ice during freezing. The objective of this study was to characterize the rye AFPs in their native forms, and our results show that these proteins form oligomeric complexes in vivo. Nine proteins were separated by native-polyacrylamide gel electrophoresis from apoplastic extracts of cold-acclimated winter rye leaves. Seven of these proteins exhibited multiple polypeptides when denatured and separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. After isolation of the individual proteins, six were shown by immunoblotting to contain various combinations of GLP, CLP, and TLP in addition to other unidentified proteins. Antisera produced against individual cold-induced winter rye GLP, CLP, and TLP all dramatically inhibited glucanase activity in apoplastic extracts from cold-acclimated winter rye leaves, and each antiserum precipitated all three proteins. These results indicate that each of the polypeptides may be exposed on the surface of the protein complexes. By forming oligomeric complexes, AFPs may form larger surfaces to interact with ice, or they may simply increase the mass of the protein bound to ice. In either case, the complexes of AFPs may inhibit ice growth and recrystallization more effectively than the individual polypeptides.

Gain control of NMDA-receptor currents by intracellular sodium

The influx of Na+ is fundamental to electrical signalling in the nervous system and is essential for such basic signals as action potentials and excitatory postsynaptic potentials. During periods of bursting or high levels of discharge activity, large increases in intracellular Na+ concentration ([Na+]i) are produced in neuronal soma and dendrites. However, the intracellular signalling function of raised postsynaptic [Na+]i is unknown. Here we show that [Na+]i regulates the function of NMDA (N-methyl-D-aspartate) receptors, a principal subtype of glutamate receptor. NMDA-receptor-mediated whole-cell currents and NMDA-receptor single-channel activity were increased by raising [Na+]i and channel activity decreased upon lowering [Na+]i; therefore, the activity of NMDA channels tracks changes in [Na+]i. We found that the sensitivity of the channel to Na+ was set by a Src kinase that is associated with the channel. Raising [Na+]i selectively increased synaptic responses mediated by NMDA receptors, but not by non-NMDA receptors. Thus, the change in postsynaptic [Na+]i that occurs during neuronal activity is a signal for controlling the gain of excitatory synaptic transmission. This mechanism may be important for NMDA-receptor-dependent plasticity and toxicity in the central nervous system.

[Studies on clinical epidemiology of Tsutsugamushi disease of the autumn-winter type in the easten suburbs of Jinan]

This paper reported the epidemiological characteristics of 154 cases under investigation for tsutsugamushi disease of autumn-winter type in the eastern suburb of Jinan. Results showed that the characteristics differed greatly from those in the southern part of China. Majority of patients had toxic symptoms due to infections but specific characteristics were less obvious. Eschars and ulcers appeared only in 14.94% of the cases and occurred only in autumn-winter season. Clinically mild cases constituted the majority. Cases not only distributed sporadically, but also had multi-organ lesions (MOL). Young peasants seemed to be most vulnerable. The pathogen of the disease belonged to low virulent strain. Serological typing belonged to the Gilliam type. The diagnosis and the treatment of the disease were discussed. Specific serum IgG of the disease was detected 6 years after convalescence.

NMDA channel regulation by channel-associated protein tyrosine kinase Src

The N-methyl-D-aspartate (NMDA) receptor mediates synaptic transmission and plasticity in the central nervous system (CNS) and is regulated by tyrosine phosphorylation. In membrane patches excised from mammalian central neurons, the endogenous tyrosine kinase Src was shown to regulate the activity of NMDA channels. The action of Src required a sequence [Src(40-58)] within the noncatalytic, unique domain of Src. In addition, Src coprecipitated with NMDA receptor proteins. Finally, endogenous Src regulated the function of NMDA receptors at synapses. Thus, NMDA receptor regulation by Src may be important in development, plasticity, and pathology in the CNS.

[Study on the mode of transmission of EHFV among host animals and its epidemiologic significance]

In our study, IFA was adopted to detect the epidemic haemorrhagic fever virus (EHFV) antigen and antibody. We studied on the mode of transmission of EHFV in mice and its epidemiologic significance. The results demonstrated that both horizontal and vertical modes of transmission existed in mice under natural circumstances. Horizontal transmission was noticed as the major mode of transmission of EHFV in mice which played an important role in the spread and development of EHF natural foci. Vertical transmission seemed to act merely on the maintenance of EHF natural foci in mice.

Ca(2+)-independent reduction of N-methyl-D-aspartate channel activity by protein tyrosine phosphatase

Regulation of ion channel function by intracellular processes is fundamental for controlling synaptic signaling and integration in the nervous system. Currents mediated by N-methyl-D-aspartate (NMDA) receptors decline during whole-cell recordings and this may be prevented by ATP. We show here that phosphorylation is necessary to maintain NMDA currents and that the decline is not dependent upon Ca2+. A protein tyrosine phosphatase or a peptide inhibitor of protein tyrosine kinase applied intracellularly caused a decrease in NMDA currents even when ATP was included. On the other hand, pretreating the neurons with a membrane-permeant tyrosine kinase inhibitor occluded the decline in NMDA currents when ATP was omitted. In inside-out patches, applying a protein tyrosine phosphatase to the cytoplasmic face of the patch caused a decrease in probability of opening of NMDA channels. Conversely, open probability was increased by a protein tyrosine phosphatase inhibitor. These results indicate that NMDA channel activity is reduced by a protein tyrosine phosphatase associated with the channel complex.

The major transcriptional transactivation domain of simian virus 40 large T antigen associates nonconcurrently with multiple components of the transcriptional preinitiation complex

Simian virus 40 (SV40) large T antigen (Tag) is a promiscuous transcriptional transactivator; however, its mechanism of transactivation remains unknown. Recent studies have suggested the possible involvement of protein-protein interactions with TBP, the TATA box-binding protein of TFIID, and TEF-1, an enhancer-binding factor. We show here that (i) the Tag domain containing amino acids 133 to 249 directly interacts with the general transcription factor TFIIB, the activator protein Sp1, and the 140-kDa subunit of RNA polymerase II, as well as with TBP and TEF-1; (ii) these interactions can also occur when these transcription factors are present in their functional states in cellular extracts; (iii) binding of Tag to TBP is eliminated by preincubation of TBP either at 48 degrees C or with the adenovirus 13S E1a protein; (iv) this domain of Tag cannot bind concurrently to more than one of these transcription factors; and (v) the substitution of Tag amino acid residues 173 and 174 inactivates the ability of this Tag domain both to associate with any of these transcription factors and to transactivate the SV40 late promoter. Thus, we conclude that SV40 Tag probably does not transactivate via the concurrent interaction with multiple components of the preinitiation complex. Rather, we hypothesize that transactivation by Tag may primarily occur by removing or preventing the binding of factors that inhibit the formation of preinitiation complexes.

Photosynthetic Carbon Metabolism and Translocation in Wild-Type and Starch-Deficient Mutant Nicotiana sylvestris L

A high rate of daytime export of assimilated carbon from leaves of a starch-deficient mutant tobacco (Nicotiana sylvestris L.) was found to be a key factor that enabled shoots to grow at rates comparable to those in wild-type plants under a 14-h light period. Much of the newly fixed carbon that would be used for starch synthesis in leaves of wild-type plants was used instead for sucrose synthesis in the mutant. As a result, export doubled and accumulation of sucrose and hexoses increased markedly during the day in leaves of the mutant plants. The increased rate of export to sink leaves appeared to be responsible for the increase in the proportion of their growth that occurred during the day compared to wild-type plants. Daytime growth of source leaves also increased, presumably as a result of the increased accumulation of recently assimilated soluble carbon in the leaves. Even though starch accumulation did not occur in the leaves of mutant plants, nearly all the sugar that accumulated during the day was exported in the period of decreasing irradiance at the end of the diurnal light period. Changes in carbon allocation that occurred in leaves of wild-type and mutant plants near the end of the light period appeared to result from endogenous diurnal regulation associated with the day-night transition.

Amino- and carboxyl-terminal domains specify the identity of the delta subunit in assembly of the mouse muscle nicotinic acetylcholine receptor

We have used transient expression in COS cells of the subunits of the nicotinic acetylcholine receptor (AChR) from mouse skeletal muscle to investigate the role of transmembrane and cytoplasmic domains of the delta subunit in assembly of the AChR. When chimeric subunits whose extracellular amino- and carboxyl-terminal domains were from the delta subunit and whose transmembrane and cytoplasmic domains were from either the beta, gamma, or epsilon subunit were expressed with alpha, beta, and epsilon subunits, alpha-bungarotoxin-binding activity appeared on the surface of the transfected cells. The resulting receptor complexes each had sedimentation constants resembling those of the native AChR, consistent with a pentameric structure. Further investigation of the delta beta chimeric subunit showed that it formed a heterodimer with the alpha subunit and that the resulting subunit bound d-tubocurarine with an affinity similar to that of the alpha delta heterodimer; delta beta also formed a heterodimer with a form of the alpha subunit that is truncated after the first transmembrane domain. A heterodimer formed from the epsilon beta and alpha subunits also bound d-tubocurarine with an affinity similar to that of the alpha epsilon heterodimer. When both epsilon beta and delta beta subunits were substituted for the epsilon and delta subunits, respectively, a receptor complex was formed whose structure appeared to be alpha 2 beta(epsilon beta)(delta beta). These results show that, as with the epsilon subunit, the identity of the delta subunit in AChR assembly arises from the extracytoplasmic domains of the subunit.

[Detection of cervical human papillomavirus infection from women with external genital condyloma acuminata]

Cervical biopsy specimens were taken from 36 women with external genital condyloma acuminata in order to diagnose a concomitant cervical human papillomavirus (HPV) infection. Positive HPV infection rate of cervix was 16% (6/36) by routine visual examination, 69% (25/36) by colposcopy and 56% (18/32) by pathology. Among those patients 31% (10/32) have grade I-II cervical intraepithelial neoplasia (CIN) according to pathology. In 8 cases, both vulva and cervical specimens were examined by Southern blot, dot blot and polymerase chain reaction (PCR) technique. HPV DNA positive was detected in 7 of 8 cervical specimens. It is concluded cervical HPV infection was rather common in women with external genital condyloma acuminata and it is valuable to examine cervical HPV infection by colposcopy and biopsy to detect the concomitant CIN.

Administration of opiate antagonist naloxone induces recurrence of increased jaw muscle activities related to inflammatory irritant application to rat temporomandibular joint region

1. Our recent studies in rats have demonstrated that the small-fiber excitant and inflammatory irritant mustard oil injected into the temporomandibular joint (TMJ) region can evoke a sustained and reversible increase of electromyographic (EMG) activity in jaw muscles and an acute inflammatory response. The aim of the present study was to test if opioid mechanisms are involved in modulating the EMG increase evoked by mustard oil. 2. Mustard oil injected into the rat TMJ region evoked significant increases of jaw muscle EMG activity; the vehicle mineral oil had no such effect. The increased EMG activity lasted up to 20 min, and by 30 min after the mustard oil injection had returned to control (preinjection) levels, at which time administration of the opiate antagonist naloxone (1.3 mg/kg i.v.) induced a significant recurrence of the increase in EMG activity. This "rekindling" of EMG activity appeared at 5 to 10 min after the naloxone administration and lasted for 10 to 20 min. In contrast, naloxone administration in the animals receiving mineral oil injection into the TMJ region did not "rekindle" the EMG activity, nor did the administration of the peripherally acting opiate antagonist methylnaloxone or the vehicle of naloxone. 3. These findings reveal that the application of the opiate antagonist naloxone produces a recurrence of increased jaw muscle activity reflexively evoked by mustard oil injection into the rat TMJ region. They suggest that central opioid depressive mechanisms activated by the mustard oil-induced afferent barrage limit the duration of the evoked EMG changes.

Vasopressin and vasopressin-receptor immunoreactivity in small-cell lung carcinoma (SCCL) cell lines: disruption in the activation cascade of V1a-receptors in variant SCCL

Four classical and three variant small-cell carcinoma of the lung (SCCL) cell lines were examined for vasopressin and vasopressin V1a-receptor immunoreactivity. One of these classical cell lines, NCI-H345, and one variant cell line, NCI-H82, were further investigated for binding of V1 and V2 vasopressin-receptor antagonists, vasopressin-induced calcium mobilization, and vasopressin-induced thymidine uptake. All classical and variant SCCL cell lines examined contained vasopressin and vasopressin-receptors as determined by immunocytochemistry. Both NCI-H82 and NCI-H345 demonstrated similar binding patterns with the V1 and V2 vasopressin-receptor antagonists, indicating the presence of both receptor subtypes. For the classical cell line (NCI-H345), vasopressin (1 microM) induced an increase in cytosolic free calcium, while the peptide was ineffective at increasing cytosolic calcium in the variant cell line (NCI-H82). However, vasopressin (0.1 or 1 microM) was unable to stimulate thymidine uptake in the classical (NCI-H345) or variant (NCI-H82) cell lines for the conditions used. These results indicate that both classical and variant SCCL produce vasopressin, and vasopressin V1a and V2 receptors. In the variant cell line, there appears to be a disruption in the activation cascade for V1a receptors as indicated by the lack of vasopressin-induced calcium mobilization.

A sequence in the main cytoplasmic loop of the alpha subunit is required for assembly of mouse muscle nicotinic acetylcholine receptor

We have investigated the role of intracellular cytoplasmic sequences in the assembly of the mouse muscle nicotinic acetylcholine receptor (AChR) transiently expressed in COS cells. A chimeric protein in which the region from M1 to M4 of the alpha subunit was replaced by the corresponding region in the beta subunit was unable to support AChR assembly when substituted for the alpha subunit; a chimeric alpha subunit containing only the long cytoplasmic loop from the beta subunit was likewise inactive. Systematic mutation of short segments of the loop identified a sequence of 17 amino acids near the C-terminal end of the loop for which the beta sequence could not be substituted. Each of the inactive chimeric and mutated alpha subunits bound alpha-bungarotoxin when expressed alone and formed a heterodimer when expressed with the delta subunit. An alpha subunit truncated after M1 formed both an alpha delta heterodimer and an alpha delta beta heterotrimer, demonstrating that the cytoplasmic loop is dispensable for the early steps of assembly. A sequence in the long cytoplasmic loop of the alpha subunit thus appears to play a role in a late step of AChR assembly.

Products of vasopressin gene expression in small-cell carcinoma of the lung

Small-cell neuroendocrine carcinoma of the lung is known to express products related to the vasopressin gene, although these products have been reported to sometimes differ from those generated by neurones of the hypothalamo-neurohypophyseal system. To further investigate vasopressin gene expression in neuroendocrine carcinomas, we performed immunohistochemistry on 24 histologically classified small-cell carcinomas using antibodies directed against different regions of the vasopressin precursor. All of the tumours examined contained at least two parts of the vasopressin precursor, suggesting that vasopressin might have a biological role in these tumours and indicating a role for these products in tumour diagnosis and treatment. Sixty-seven per cent of the tumours contained immunoreactivity for all major regions of the precursor: vasopressin, vasopressin-associated human neurophysin, the bridging region between the hormone and the neurophysin, and vasopressin-associated human glycopeptide. However, 33% of the tumours examined appeared to express only part of the vasopressin precursor, as evidenced by the absence of immunoreactivity for the neurophysin and/or the glycopeptide. These results support the proposition that both normal and abnormal vasopressin gene expression occurs in small-cell carcinoma of the lung.

The role of the cytoplasmic domains of individual subunits of the acetylcholine receptor in 43 kDa protein-induced clustering in COS cells

The 43 kDa protein, a cytoplasmic peripheral membrane protein, is closely associated with the acetylcholine receptor (AChR) at the neuromuscular junction, where it is thought to anchor the receptor in the postsynaptic membrane. We have used the 43 kDa protein-induced clustering of AChRs that occurs when both proteins are transiently expressed in COS cells to investigate which parts of the AChR might interact with the 43 kDa protein. By constructing chimeric subunits, we showed that the cytoplasmic domains of neither the epsilon nor delta subunits are required for 43 kDa protein-induced clustering. Systematic mutational analysis of the long cytoplasmic loops of the alpha and beta subunits showed that most of the loops can be altered without affecting the ability of the AChR to be clustered; in each case, however, one or more sequences could not be tested, because mutation in these regions prevented AChR assembly. Our results suggest either that these regions are involved in clustering or that the 43 kDa protein can interact with multiple, alternative sites on the cytoplasmic surface of the AChR. Our experiments also show that the postulated sites of tyrosine phosphorylation in the beta subunit and of serine phosphorylation in the alpha subunit can be mutated without affecting 43 kDa protein-induced AChR clustering.

[A comparable study of microwave tissue coagulation (MTC) and CO2 laser in treatment of cervical erosion]

In a randomized study, 300 patients with cervical erosion were allocated to either MTC(154) or CO2 Laser(146). The patients were treated on an outpatient basis without anesthesia. In the case of initial treatment failure the same method was to be used for retreatment. All the patients were followed-up for an average of 11 weeks (8-12). 142 of 154 microwave-coagulated patients (92.20%) and 116 of 146 Laser-evaporated patients (79.45%) were cured after one treatment, and there was significant difference between MTC and Laser group (P < 0.005). Bleeding during operation occurred in 5 of 154 MTC group (3.25%) and 32 of 146 Laser group (21.92) (P < 0.005). The result suggested that MTC had higher cure rate and less complications. It is easy to handle, safe and economic.

Differential effects of cutaneous and deep application of inflammatory irritant on mechanoreceptive field properties of trigeminal brain stem nociceptive neurons

1. The aim of this study was to determine whether there are differential neuroplastic effects of cutaneous and deep stimuli on the mechanoreceptive field (RF) properties of nociceptive brain stem neurons recorded in trigeminal (V) subnucleus caudalis. 2. A total of 31 caudalis neurons were functionally identified in anesthetized rats as nociceptive neurons receiving convergent cutaneous and deep afferent inputs, and the effects of the small-fiber excitant and inflammatory irritant mustard oil applied to either tongue muscle or facial skin were tested on their cutaneous and deep RFs. 3. The expression of neuroplasticity on the cutaneous and deep RFs of the neurons was found to depend on the site of application of this irritant. Mustard oil injected into the tongue muscle produced a significant and reversible expansion of both the cutaneous and deep RFs. In contrast, application of mustard oil to facial skin resulted in a significant and reversible expansion of the cutaneous RF, but no deep RF expansion occurred. 4. These findings suggest that considerable functional neuroplasticity of the cutaneous and deep RF properties of V nociceptive neurons can be induced by a peripheral inflammatory irritant and that deep inputs are especially effective in evoking these neuroplastic changes.

The properties of an HBV surface antigen protein carrying the binding site for the receptor of hepatocytes--its formation of surface antigen particles and secretion from discrete cell lines

A human hepatitis B virus (HBV) gene, which encodes the major surface antigen protein (S protein) carrying the hepatocyte receptor-binding site, was constructed with site-directed mutagenesis and in vitro recombination. When expressed in monkey kidney cell line COS-M6, this gene product (S309 protein) formed surface antigen (HBsAg) particles and secreted from the cells. It was stable within the cells and in the culture medium and could be immunoprecipitated with antisera directed against plasma-derived HBsAg or synthetic preS1 polypeptide. Isopycnic CsCl gradient centrifugation showed that the density of S309 protein particles (1.25 g/ml) was slightly higher than that of S protein particles. The S309 protein was readily secretable from hepatoma cell lines, and the amount secreted was comparable to that of the S protein. By contrast, only about 10% of the S309 protein was secreted from COS-M6 cells, and its appearance in culture medium was delayed. The efficiency of the secretion of the S309 protein can be improved when it is coexpressed with the S protein.

Biosynthesis of vasopressin by gastrointestinal cells of Brattleboro and Long-Evans rats

The distribution of vasopressin, provasopressin, vasopressin-associated neurophysin, and vasopressin-associated glycopeptide was determined immunohistochemically in the gastrointestinal system of Brattleboro and Long-Evans rats. Cells containing immunoreactivity for vasopressin, provasopressin, neurophysin, and glycopeptide were detected in the same cell types of the stomach and duodenum, while selected cells in the duodenum contained only immunoreactive glycopeptide. Unlike that in the hypothalamus, staining for neurophysin in the gastrointestinal tract was sensitive to fixation. These findings indicate that vasopressin is produced by cells in the rat gastrointestinal system and suggest the existence of synthetic pathways different from those found in hypothalamic neurons.

Appearance of new receptive fields in rat dorsal horn neurons following noxious stimulation of skeletal muscle: a model for referral of muscle pain?

To test the hypothesis that painful stimuli to skeletal muscle lead to a widespread unmasking of synaptic connections in dorsal horn neurons, intramuscular injections of bradykinin (BKN) were made outside the receptive fields (RFs) of these cells in the rat. Following BKN injections, new RFs all of which were located in the deep tissues and had high mechanical thresholds appeared in 9 out of 21 (42.8%) nociceptive dorsal horn neurons which originally had a single RF in deep tissues or in the skin. The appearance of new RFs may lead to a mislocation of the source of pain if in fact the impulse activity of a nociceptive dorsal horn neuron contains information on the site of the stimulus.

Vasopressin mRNA and neurophysin-related cell-surface antigen (NRSA) in small-cell carcinoma

Production by small-cell carcinoma (SCCL) of neurophysins (HNPs) and neurophysin-related cell-surface antigen (NRSA) was examined for two cell lines, for mouse xenografts, and for a resected human tumor, using polyclonal and monoclonal antibodies to vasopressin-associated human neurophysin (VP-HNP) and polyclonal antibodies to vasopressin (VP). The nature of the mRNA responsible for giving rise to these neurophysin-related products was investigated by performing Northern analysis on preparations of poly A+RNA and cDNA probes complimentary to portions of the exon A, exon B, and exon C regions of the human VP gene. SDS-electrophoresis and Western analysis revealed two prominent proteins of 42,000 and 20,000 Da in acid extracts from all SCCL sources when the monoclonal anti-HNP or one of the two polyclonal anti-HNP preparations were used. These antibodies also disclosed the presence of a minor component of 10,000 Da. A second polyclonal anti-HNP preparation reacted with one prominent protein of 30,000 Da and, for one cell line and mouse xenografts, another protein of 32,000 Da. Both of two anti-VP preparations reacted with proteins of 42,000, 30,000, 25,000, and 20,000 Da in extracts from all SCCL source material. The immunoreactive proteins of 42,000, 30,000, and 20,000 Da were all components of a membrane fraction from SCCL cells and tissues. In Northern analysis, a single RNA of about 900 bases hybridized with exon A and exon B probes, but not with the cDNA probe complimentary to exon C of the VP gene.(ABSTRACT TRUNCATED AT 250 WORDS)

[An epidemiological survey of blindness and low vision in Shandong Province]

An epidemiological survey of blindness and low vision was carried out in a sample population of 115 167 in Shandong Province to find that the prevalence of binocular blindness was 0.34%, that of unilateral blindness 0.65%, that of binocular low vision 0.46%, and that of unilateral low vision 0.64%. The prevalence rates increased with age and the leading causes of blindness, in order of importance, were cataract, corneal diseases and glaucoma in urban areas, and cataract, corneal diseases and retinal diseases in rural areas.

An HBV large surface antigen protein which can be secreted from mammalian cells

The N-terminal 54 base pairs (encoding amino acid residues 2-19) within the preS1 region of the human hepatitis B virus surface antigen gene were deleted by site-directed mutagenesis. Unlike the wild type large surface antigen protein, when this mutated gene was expressed in monkey kidney cell line COS-M6, the protein product (S301 protein) could be secreted from the cells. Moreover, the inhibition of the secretion of the major surface antigen protein by this altered large surface antigen protein was greatly reduced, suggesting that the deleted region contained a retention sequence which prevented the secretion of the large surface antigen. However, the coexpression of the major S protein was essential for the secretion of the S301 protein. When coexpressed, the secretion of these two proteins was synchronous. Like the wild type large surface antigen protein, the S301 protein could be translocated into endoplasmic reticulum and glycosylated after its synthesis in COS cells. The S301 protein was thermostable and proteinase-resistant. It also retained the antigenicity of the large S and major S proteins. Given the fact that the S301 protein is readily secretable, stable and identical to the large S protein in terms of their antigenicity, it may be developed into a new generation of recombinant vaccine for the prevention of viral hepatitis.

Expression from herpesvirus promoters does not relieve the intron requirement for cytoplasmic accumulation of human beta-globin mRNA

Expression plasmids were constructed in which the human beta-globin gene or a variant of it precisely lacking its two introns was transcribed from its own promoter, the herpes simplex virus type 1 thymidine kinase (HSV-tk) promoter, or the immediate early promoter of human cytomegalovirus (CMV-IE). Forty two hours after transfection of these plasmids into monkey kidney cells, nuclear and cytoplasmic RNA were isolated. Quantitative S1 nuclease mapping and primer extension analysis were used to determine the relative abundances, cellular locations, and leader sizes of the accumulated beta-globin RNAs. Whereas transcripts of all of the intron-containing genes accumulated in the cytoplasm to high levels, transcripts of their cDNA variants were neither stably maintained in the nucleus nor accumulated in the cytoplasm, irrespective of the promoter from which transcription was driven. We conclude that the intron requirement for cytoplasmic accumulation of beta-globin RNA can not be circumvented by synthesis from either the promoter of the intronless HSV-tk gene or the CMV-IE promoter.