[The imaging presentations of the fallopian canal cerebrospinal fluid leaking]

Objective: To summarize the imaging presentations of the fallopian canal cerebrospinal fluid leaking (FCCFL). Methods: The high resolution CT (HRCT)and MRI materials of 4 patients (4 ears) with FCCFL confirmed by surgery between August 2016 to November 2023 were retrospectively analyzed. Among these, there were 2 males and 2 females, their ages ranged from 6 to 69 years. Results: All of the FCCFL were unilateral, including 2 on the left and 2 on the right.Clinically, the patients with FCCFL suffered from clear nasal fluid flow, ear tightness, and hearing loss. On CT, all of the affected ears were depicted markedly dilatation of the proximal portion of fallopian canal(FC), the labyrinthine segment and geniculate fossa were involved in 4 cases, and involvement of tympanic segment in 1 case at the same time. The geniculate fossa in the affected side were significantly enlarged, protruding upwards into the tympanic cavity, with one case simultaneously involving the cochlea. On MRI, the hyposignal on T1WI and hypersignal on T2WI or water sequence like cerebrospinal fluid (CSF) were shown in the enlargement FC, without diffusion restriction, and non-enhancing with administration Gadolinium contrast.CSF-like signal effusion was shown in all of the affected tympanum, of which, the CSF-like signal effusion was demonstrated in the area along the superficial petrosal nerve, the right pterygopalatine fossa and the parapharyngeal space. The adjacent intracranial meninges were presented thickening in 3 cases. Conclusion: The imaging appearances of FCCFL present some characteristics:on HRCT, the proximal portions of the affected FC depicts markedly enlargement,especially the geniculate fossa.While they present CSF-like signal, no diffusion restriction, and no enhancement administration, Gadolinium contrast on MRI, accompanying the CSF-like signal effusion in the affected tympanum.

[Clinical analysis of retropharyngeal lymph node metastasis in patients with hypopharyngeal squamous cell carcinoma]

Objective: To analyze the incidence and the related risk factors of retropharyngeal lymph node metastasis in patients with hypopharyngeal squamous cell carcinoma, evaluate the accuracy of preoperative enhanced CT in judging retropharyngeal lymph node metastasis, and investigate the impact of retropharyngeal lymph node metastasis on the prognosis. Methods: Retrospective analyses were made on 398 patients with hypopharyngeal squamous cell carcinoma who underwent surgery as the primary therapy and accepted retropharyngeal lymph node exploration and clearance during surgery in Shandong Provincial ENT Hospital from January 2014 to December 2019. Multivariate logistic regression analysis was used to clarify the related risk factors of retropharyngeal lymph node metastasis. Multivariate Cox regression analysis was used to investigate the impact of retropharyngeal lymph node metastasis on prognosis. The retropharyngeal lymph nodes of 218 cases with available preoperative enhanced CT images were evaluated by two experienced radiologists and compared with postoperative pathological results. Results: Retropharyngeal lymph node metastasis were confirmed in 54 of 398 (13.6%) cases according to postoperative pathology. The sensitivity and specificity of preoperative enhanced CT in the diagnosis of retropharyngeal lymph node metastasis were 34.6% and 91.1%, respectively, and the overall accuracy was 84.4%. Multivariate logistic regression analysis showed that the site of the primary lesion and pathological N stage were independent risk factors for retropharyngeal lymph node metastasis in hypopharyngeal squamous cell carcinoma. Patients with primary lesion located in the posterior wall of hypopharynx (OR=4.83, 95% CI: 1.27-18.40), N2 stage (OR=6.30, 95% CI: 2.25-17.67), and N3 stage (OR=26.89, 95% CI: 5.76-125.58) were prone to retropharyngeal lymph node metastasis. The 5-year overall survival rate of the 398 patients was 50.4%, and the 5-year disease-free survival rate was 48.3%. Multivariate Cox regression analysis showed that T stage, N stage, retropharyngeal lymph node metastasis, and radiotherapy were independent influencing factors for overall survival (T stage: HR=1.28, 95% CI: 1.06-1.54; N stage: HR=1.26, 95% CI: 1.14-1.40; retropharyngeal lymph node metastasis: HR=2.13, 95% CI: 1.47-3.08; radiotherapy: HR=0.54, 95% CI: 0.38-0.76) and disease-free survival of patients with hypopharyngeal squamous cell carcinoma (T stage: HR=1.26, 95% CI: 1.06-1.51; N stage: HR=1.25, 95% CI: 1.13-1.37; retropharyngeal lymph node metastasis: HR=2.24, 95% CI: 1.56-3.21; radiotherapy: HR=0.55, 95% CI: 0.40-0.77). Conclusions: Metastasis of retropharyngeal lymph nodes in hypopharyngeal squamous cell carcinoma is not rare. Enhanced CT is of low accuracy and limited value in diagnosing retropharyngeal lymph node metastasis. Primary lesions located in the posterior wall of the hypopharyngx, N2 stage, and N3 stage are independent high-risk factors for retropharyngeal lymph node metastasis. The prognosis of hypopharyngeal cancer patients with retropharyngeal lymph node metastasis is worse, and active surgical exploration and clearance can effectively reduce the mortality caused by retropharyngeal lymph node metastasis.

[Risk factors of intracranial hemorrhage with 125I seeds for the treatment of brain tumors]

Objective: To analyze the risk factors of intracranial hemorrhage after implanting 125-iodine seeds for brain tumors. Methods: A total of 234 patients with intracranial tumors receiving treatment of 125-iodine seeds from March, 2013 to November, 2020 were retrospectively analyzed. Patients were divided into bleeding group and non-bleeding group according to whether postoperative intracranial hemorrhage was reported. Univariate and multivariate analysis was performed by logistic regression to determine the independent risk factors of intracranial hemorrhage. Result: A total of 22 cases (9.4%) reported postoperative intracranial hemorrhage in 234 patients treated with 125-iodine seeds. Univariate analysis showed that the type of tumor and the history of anti-angiogenic drug within one month were possible risk factors (P<0.1). Multivariate logistic regression analysis showed that anti-angiogenic drug within one month was the independent risk factor for intracranial hemorrhage (P<0.05). Conclusions: The application of anti-angiogenic drugs within one month is the independent risk factor of intracranial hemorrhage with 125-iodine seeds for the treatment of brain tumors.

Takotsubo Syndrome: Finally Emerging From the Shadows?

It is now 30 years since Japanese investigators first described Takotsubo Syndrome (TTS) as a disorder occurring mainly in ageing women, ascribing it to the impact of multivessel coronary artery spasm. During the intervening period, it has become clear that TTS involves relatively transient vascular injury, followed by prolonged myocardial inflammatory and eventually fibrotic changes. Hence symptomatic recovery is generally slow, currently an under-recognised issue. It appears that TTS is induced by aberrant post-β₂-adrenoceptor signalling in the setting of "surge" release of catecholamines. Resultant activation of nitric oxide synthases and increased inflammatory vascular permeation lead to prolonged myocardial infiltration with macrophages and associated oedema formation. Initially, the diagnosis of TTS was made via exclusion of relevant coronary artery stenoses, plus the presence of regional left ventricular hypokinesis. However, detection of extensive myocardial oedema on cardiac MRI imaging offers a specific basis for diagnosis. No adequate methods are yet available for definitive diagnosis of TTS at hospital presentation. Other major challenges remaining in this area include understanding of the recently demonstrated association between TTS and antecedent cancer, the development of effective treatments to reduce risk of short-term (generally due to shock) and long-term mortality, and also to accelerate symptomatic recovery.

Structure of a two-dimensional superparamagnetic system in a quadratic trap

Ground-state structures of a two-dimensional (2D) system composed of superparamagnetic charged particles are investigated by means of molecular dynamics simulation. The charged particles trapped in a quadratic potential interact with each other via the repulsive, attractive, and magnetic dipole-dipole forces. Simulations are performed within two regimes: a one-component system and a two-component system where the charged particles have the identical charge-to-mass ratio. The effects of magnetic dipole-dipole interaction, mixing ratio of the two species and confinement frequency on the ground-state structures are discussed. It is found that as the strength of the magnetic dipole increases, the charged particles tend to self-organize into chainlike structures. The two species particles exhibit different structural features, depending on the competition of electrostatic repulsive interaction, magnetic dipole-dipole interaction and confinement force. The potential lanes are observed through analyzing the global potential of the magnetic particles, which guide the unmagnetic particles aligning themselves in the direction of the potential lanes.

[Feasibility of the determination of plasma vardenafil level in rat by performance liquid chromatography-tandem mass spectrometry]

Objective: To develope and validate a reliable and sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for determination of vardenafil concentration in plasma of rat. Methods: Plasma samples of normal Sprague-Dawley rats were collected. A Phenomenex Synergi Polar-RP 80A column (2.0 mm×50 mm, 4 µm) was used. Column temperature was set at 30 ℃. Mobile phase A was 0.1% formic acid in water; mobile phase B was 0.1% formic acid in acetonitrile. The flow rate was 0.4 ml/minutes. Quantitative determination was performed by electrospray ionization, operating in positive ion multiple reaction monitoring (MRM) mode. Cisapride was used as the internal standard. The feasibility of the method was evaluated by examining its specificity, linearity and quantitative range, precision and accuracy, matrix effects, and stability. Results: Under the selected chromatographic and mass spectrometry conditions, the monitoring ions of vardenafil and internal standard were mass-to-charge ratio（m/z) 489.3/151.2 and 466.4/234.2, the retention times of vardenafil and internal standard were 2.62 and 2.80 minutes, respectively, and the peak shape was satisfactory. The method has good linearity in the concentration range of 0.2-200 ng/ml. The intra-batch precision (%CV) and accuracy (%DEV) of vardenafil were 1.5%-9.7% and -6.8%-6.6%, respectively. The inter-batch precision and accuracy of vardenafil were 3.1% -8.4% and -3.7%-4.6%, respectively. In this sample processing method, the extraction recovery rate of vardenafil was obtained at range of 88.2%-104.6%, which met the requirements for the investigation of extraction recovery rate. In this sample processing method, the normalized matrix factor of each quality control concentration of vardenafil was 1.04, 0.85, and 1.04, and the coefficient of variation (%CV) was in the range of 1.7%-10.7%, which met the requirements for the investigation of matrix effects. Variations of short-term stability, long-term stability, and stability of 4 freeze-thaw cycles of vardenafil was within ±15%, and the coefficient of variation were within 5%. Conclusion: The high performance liquid chromatography-tandem mass spectrometry method established in this study is feasible for the measurement of concentration of vardenafil in rat plasma and this method has good specificity and high accuracy, and can be used to detect the concentration of vardenafil in rat plasma.

[Analysis of spatial-temporal distribution of pesticide poisoning in Quzhou, 2013-2017]

Objective: To analysis the epidemic and spatial characteristics of pesticide poisoning in Quzhou during 2013-2017, and to provide scientific basis for the prevention and control of influenza in Quzhou in the future. Methods: The incidence data of pesticide poisoning from January 1, 2013 to December 31, 2017 in Quzhou collected from China Information System For Disease Control And Prevention. The descriptive analysis conducted by using SPSS18.0 software, and the Sa T Scan 9.2 software was used to complete space-time scan. Finally, ArcMap10.2 software was used to visualize the results. Results: There were 1819 cases of pesticide poisoning in Quzhou from 2007 to 2016, among which 298 cases were reported for productive poisoning, the incidence peak was from August to September, the highest number of patients in productive poisoning was in the age group of 46-60 years old and over 61 years old, with 109 patients in each group, and the number of male patients was significantly higher than that of female (χ(2)=63.857, P<0.01) . 1521 cases of non-productive pesticide poisoning were reported, among which the proportion of suicide poisoning (57.65%) was far higher than that of accidental poisoning (28.97%) , the number of female suicide poisoning was higher than that of male (χ(2)=5.510, P=0.019) , the proportion of accidental poisoning was the highest in the ≤15 years age group (89.00%, 89/100) , furthermore the number of suicide poisoning was the highest in the ≥61 years age group (314) . The incidence of pesticide poisoning could be detected by temporal-spatial scanning statistics, the time clustering is from August to September, the spatial clustering is in Jiangshan city, there are consistent with the descriptive of pesticide poisoning. Conclusion: The pesticide poisoning in Quzhou is mainly caused by non-productive suicide poisoning, and the spatial clustering is in Jiangshan city. Relevant departments should carry out targeted prevention and control measures according to the different characteristics of pesticide poisoning in clustered and non-clustered areas.

[Characteristics of HIV-infected persons without long term disease progress and related factors in Guangxi Zhuang Autonomous Region]

Objective: To understand the characteristics of HIV infected persons without long term disease progress [also known as long term non-progressors (LTNPs)], and related factors in Guangxi Zhuang Autonomous Region (Guangxi). Methods: Data of persons living with HIV and receiving no antiretroviral therapy in Guangxi by the end of 2016 were collected from the national HIV/AIDS comprehensive control and prevention information system of China. Results: By the end of 2016, there were 313 LTNPs in Guangxi, accounting for 2.3% of those being reported for more than 10 years, 5.4% of those being reported for more than 10 years and surviving, and 26.6% of those being reported for more than 10 years, surviving and receiving no antiretroviral therapy. Among the LTNPs, 87.2%(273) were men, 94.9% (297) were aged ≤ 40 years, 32.3% (101) were farmers, 55.6% (174) were single, divorced or widowed, 69.3% (217) were of Han ethnic group, 68.1% (213) were injecting drug users, and 52.1% (163) were from custody facilities. Multiple logistic regression analysis indicated that factors associated with delayed disease progression included age ≤40 years (compared with age >40 years, aOR=1.55, 95%CI: 1.31-3.12) and injection drug use (compared with sexual transmission, aOR=1.23, 95%CI: 1.10-1.74). Conclusions: A number of LTNPs existed in HIV-infected individuals in Guangxi. Further research are needed to identify the related factors, and it is necessary to conduct large sample size studies on host immunology, genetics and the virology of HIV to explore the related mechanism.

Loss at 16q22.1 identified as a risk factor for intrahepatic recurrence in hepatocellular carcinoma and screening of differentially expressed genes

Copy number alteration (CNA) of chromosome 16, a frequent genetic event in tumors including hepatocellular carcinoma (HCC), has been associated with HCC etiology of hepatitis B virus (HBV) and with clinical outcomes in multiple types of cancer. This study identified CNAs in chromosome 16 in relation to intrahepatic recurrence of HCC in a population with high HBV prevalence, and further screened for differentially expressed genes in recurrence-related CNAs. Array comparative genomic hybridization and expression arrays were used to detect CNAs and gene expression differences, respectively. The associations between CNAs and intrahepatic recurrence were analyzed on 66 patients, follow-up period of 3-73 months. One hundred and nine cases were further evaluated regarding the differentially expressed genes. Losses at 16q and 16p were detected in 62.1% and 51.5% of the 66 cases, respectively. The most recurrent CNAs (with frequency >20%) were losses at 16p13.3-13.2, 16p13.11, 16q11.2-22.1, 16q22.1, 16q22.2-24.2 and 16q24.2. Of the CNAs, 16q22.1 loss was significantly associated with unfavorable intrahepatic recurrence-free survival (P = 0.025). Multivariate Cox analysis identified 16q22.1 loss as an independent risk factor for intrahepatic recurrence (HR = 2.32, 95% CI = 1.26-4.27). A panel of 21 genes, including TRADD, PSMB10, THAP11, CTCF and ESRP2, were significantly downregulated in HCCs with 16q22.1 loss compared to those without the loss. These results suggest that loss at 16q22.1 was associated with increased risk for intrahepatic recurrence of HCC, at least in the HBV-prevalence population. Multiple downregulated genes correlated with the loss were screened.

[Effect of dexmedetomidine on perioperative stress and postoperative pain in patients with radical resection of esophageal cancer under combined thoracoscope and laparoscope]

Objective: To investigate the effects of dexmedetomidine on perioperative stress and postoperative pain in patients with radical resection of esophageal cancer under combined thoracoscope and laparoscope. Methods: In this prospective study, one hundred patients undergoing radical resection of esophageal cancer in Affiliated Cancer Hospital of Zhengzhou University from January 2016 to October 2017, were randomly divided into control group (group C) and dexmedetomidine group (group D), n=50. All patients were anaesthetized (induced and maintained) with intravenous target-controlled infusion(TCl) of propofol and remifentanil, and intermittent intravenous injection of cisatracuriumbesylate. Bispectral index(BIS) was used to monitor the depth of anesthesia and maintained between 45-60 during operation.All patients received sufentanil (0.3 μg/kg) 30 min before the end of the operation and then received intravenous analgesia pump for postoperative patient controlled analgesia(PCA). Patients in group D received intravenous infusion of dexmedetomidine(1 μg/kg) 20 min before anesthesia induction, followed by intravenous pumping of dexmedetomidine(0.2 μg·kg(-1)·h(-1)) intraoperatively.Postoperative intravenous patient-controlled analgesia(PCA) was performed in all patients, with background doses of sufentanil 0.04 μg· kg(-1)·h(-1) for patients in group C, and sufentanil 0.025 μg·kg(-1)·h(-1) plus dexmedetomidine 0.1 μg· kg(-1)·h(-1) for patients in group D. The operation time, liquid input and output during operation, the number of PCA pressings after operation were recorded. At these time points: T(0)(the day before operation), T(1)(immediate before anesthesia induction), T(2)(1 h after emergence), T(3)(24 h after operation), T(4)(3 d after operation), T(5)(7 d after operation), T(6)(one month after operation), T(7)(3 months after operation) and T(8)(6 month after operation) , venous blood samples of patients were collected for detection of epinephrine, norepinephrine and corticosterone. The pain visual analogue scale(VSA) was used to assess pain levels in patients at T(2), T(3), T(4), T(5), T(6), T(7), T(8). Results: The age, sex ratio, body mass index (BMI) and ASA grading ratio in two groups were not significantly different(all P>0.05). There were no Significant differences in operation time, liquid input and blood output between group C and group D(all P>0.05). Within 24 h after operation, the sufentanil consumption in group D[(35.86±8.65)μg]was significantly less than that in group C[(59.53±15.26) μg, t=7.061, P<0.05], and the number of PCA pressing in group D(2.15±1.38) was obviously less than that in group C(5.85±2.16, t=4.971, P<0.05). Compared with group C, serum norepinephrines in group D was significantly less (t=13.276, 16.027, 14.319, 12.771, 12.296, respectively; all P<0.05) at T(1), T(2), T(3), T(4), T(5).And there were no difference between these two groups at T(0), T(6), T(7), T(8)(all P>0.05). Serum epinephrine in group D were significantly lower than them in group C at T(2), T(3), T(4), T(5) (t=6.153, 8.774, 9.127, 8.409, respectively; all P<0.05), but there were no difference between these two groups at T(0), T(1), T(6), T(7), T(8)(all P>0.05). Serum corticosterone in group D were sharply less than them in group C at T(2), T(3), T(4), T(5) (t=16.364, 15.306, 12.153, 12.592, respectively; all P<0.05), but at T(0), T(1), T(6), T(7), T(8), there were no difference between these two groups (all P>0.05). Compared with group C, the number of patients with postoperative pain(VAS score≥4) in group D was obviously less at T(6), T(7), T(8)(10 vs 20, 4 vs 12, 3 vs 10; χ(2)=4.762, 4.762, 4.332, respectively; all P<0.05). Conclusion: Perioperative application of dexmedetomidine can effectively decrease the perioperative stress response, obviously cut down the perioperative opioid consumption, and prevent the transition from postoperative acute pain to chronic pain in patients with radical resection of esophageal cancer under combined thoracoscope and laparoscope.

[Clinical applications of intelligent pressure control flexible ureteroscope for the treatment of renal calculi ≤2 cm]

Objective: To evaluate the effectiveness and safety of intelligent pressure control flexible ureteroscope for management of renal stones ≤2 cm. Methods: The clinical data of 267 cases of renal calculi treated with flexible ureteroscope lithotripsy at Department of Urology, Ganzhou People's Hospital from June 2015 to December 2017 were analyzed retrospectively. There were 129 male and 138 female patients, with a mean age of 51.2 years (ranging from 19 to 76 years). Among them, 145 patients underwent intelligent pressure control flexible ureteroscope (intelligent control group) and 122 patients underwent flexible ureteroscope ordinary (ordinary group). The t test, χ² test or Fisher exact test were used for statistical analysis. The success rate of stone seeking, the stone free rates, the incidence of complications, the average operation time, the average hospital stay after operation were compared between the two groups. Results: The average mean operative time of the patients with intelligent control group was (26.17 ± 8.64) minutes, significantly shorter than (47.23±18.35) minutes of the ordinary group (t=1.968, P=0.000). The stone free rate of the patients with intelligent control group was 97.2%, it was higher than 86.0% of ordinary group (χ²=0.069, P=0.004). The complication rate of the patients with intelligent control group was 2.7%, which was significantly shorter than 18.0% of the ordinary group (χ²=17.586, P=0.000). However, there was no significant difference between the two groups in the success rate of stone seeking and postoperative hospital stay (P>0.05). Conclusion: Intelligent controlled pressure ureteral flexible ureteroscope has the advantages of short operation time, high stone free rate and less complications in the treatment of renal calculi ≤2 cm compared with flexible ureteroscope ordinary.

Time-dependent Expression of MT1A mRNA and MT2A mRNA in the Contused Skeletal Muscle of Rats

OBJECTIVES

To investigate the time-dependent expression of metallothionein （MT） 1A mRNA and MT2A mRNA in contused skeletal muscle of rats.

METHODS

A total of 54 Sprague-Dawley rats were used in this study. The rats were divided into two parts: control group （n=6） and contusion groups （0.5, 1, 6, 12, 18, 24, 30, and 36 h after contusion, n=6）. Total RNA was extracted from skeletal muscle. The expression levels of MT1A mRNA and MT2A mRNA were detected by SYBR Green I real-time PCR.

RESULTS

The expression trends of the two potential marker genes were related to wound age. In addition to 0.5 h, there were significant contrasts between the control group and contused group （P<0.05）, about the expression levels of MT1A mRNA and MT2A mRNA in different phases. As the extension of wound age, the relative expression of MT1A mRNA and MT2A mRNA at 1 h, 6 h, 12 h and 18 h after contusion demonstrated upgrade tendency until its expression levels in 18 h peak with 239.41±15.20 and 717.42±50.76, respectively. When time extends to 24 h after injury, the expression of above two marks decreased, respectively. The MT1A mRNA and MT2A mRNA expression levels increased at 30 h and then decreased.

CONCLUSIONS

Determination of MT1A mRNA and MT2A mRNA levels by real-time PCR may be useful for the estimation of wound age.

A comprehensive review of microRNA-related polymorphisms in gastric cancer

MicroRNAs (miRNAs) are a class of small non-coding RNA molecules of about 22 nucleotides in length. miRNAs are highly conserved in both plants and animals, and function as gene regulators by binding to the 3'-untranslated region of target mRNAs for cleavage and/or translational repression. miRNA biogenesis, stability, and regulation of expression are strongly sequence dependent. Sequence variants, such as single nucleotide polymorphisms (SNPs) in pri-miRNA, pre-miRNA, promoter regions, or miRNA-target sites, can influence miRNA function, thereby contributing to the pathological features of human disease. In this review, we focus on miRNA-related SNPs in gastric cancer and comprehensively analyze some commonly studied SNPs.

LONG-TERM PRECONDITIONING OF PLANTLETS: A PRACTICAL METHOD FOR ENHANCING SURVIVAL OF PINEAPPLE (Ananas comosus Merr.) SHOOT TIPS CRYOPRESERVED USING VITRIFICATION

BACKGROUND

The purpose of this study was to develop an efficient cryopreservation protocol for pineapple (Ananas comosus Merr.) shoot tips.

OBJECTIVE

The optimal state of pineapple plantlets was investigated by using sucrose preconditioning to enhance survival after cryostorage.

METHODS

To achieve a suitable state of plantlets before cryopreservation, 0.2 M to 0.4 M sucrose concentrations combined with short- (0-7 days), medium- (15-30 days), and long-term (75-150 days) preconditioning periods were compared.

RESULTS AND CONCLUSION

The highest survival (100 %) was achieved using the following procedure: intact plantlets underwent long-term preconditioning with 0.2 M sucrose for 135 days, dissected shoot tips were treated with a loading solution containing 2.0 M glycerol + 0.4 M sucrose for 60 min at 25 degree and the shoot tips were dehydrated in PVS2 for 2h at 0 degree C before being plunged in liquid nitrogen. Rewarming was conducted in a water-bath for 30 s at 40 degree C and PVS2 was replaced with a 1.2 M sucrose solution for 30 min at 25 degree C. The shoot tips were transferred on semisolid medium and left in the dark for 1 week, then in dim light for 3 weeks.

Polymorphic microsatellite markers in the false kelpfish Sebastiscus marmoratus: isolation, characterization, and cross-species amplification

A (GT/CA)13-microsatellite-enriched genomic library of the false kelpfish Sebastiscus marmoratus was constructed, and 20 polymorphic microsatellite loci were isolated and characterized. The polymorphisms were investigated in 48 wild individuals from a single population collected from the northern Yellow Sea. The numbers of alleles per locus varied from 4-22 with an average of 9. The observed and expected heterozygosities of each locus ranged from 0.196-0.958 and from 0.487-0.942, with an average of 0.693 and 0.765, respectively. One locus significantly deviated from Hardy-Weinberg equilibrium, and one pair of loci was in linkage disequilibrium determined by Bonferroni's correction. Cross-species amplification was also conducted in the related species Inimicus japonicus, collected from East China Sea. The result showed that six loci could be amplified from I. japonicus DNAs. These polymorphic markers would be useful for assessment of genetic variation and population structure of scorpionfish.

Chronic intermittent hypoxia induces atherosclerosis by NF-κB-dependent mechanisms

Chronic intermittent hypoxia (CIH) causes atherosclerosis in mice fed a high cholesterol diet (HCD). The mechanisms by which CIH promotes atherosclerosis are incompletely understood. This study defined the mechanistic role of NF-κB pathway in CIH+HCD induced atherosclerosis. Wild type (WT) and mice deficient in the p50 subunit of NF-κB (p50-KO) were fed normal chow diet (ND) or HCD, and exposed to sham or CIH. Atherosclerotic lesions on the en face aortic preparation and cross-sections of aortic root were examined. In WT mice, neither CIH nor HCD exposure alone caused, but CIH+HCD caused evident atherosclerotic lesions on both preparations after 20weeks of exposure. WT mice on ND and exposed to CIH for 35.6weeks did not develop atherosclerotic lesions. P50 gene deletion diminished CIH+HCD induced NF-κB activation and abolished CIH+HCD induced atherosclerosis. P50 gene deletion inhibited vascular wall inflammation, reduced hepatic TNF-α level, attenuated the elevation in serum cholesterol level and diminished macrophage foam cell formation induced by CIH+HCD exposure. These results demonstrate that inhibition of NF-κB activation abrogates the activation of three major atherogenic mechanisms associated with an abolition of CIH+HCD induced atherosclerosis. NF-κB may be a central common pathway through which CIH+HCD exposure activates multiple atherogenic mechanisms, leading to atherosclerosis.

Synthesis of GaN nanotip triangle pyramids on 3C–SiC epilayer/Si substrates via an in situ In-doping technique

GaN nanotip triangle pyramids were synthesized on 3C-SiC epilayer via an isoelectronic In-doping technique. The synthesis was carried out in a specially designed two-hot-boat chemical vapor deposition system. In (99.999%) and molten Ga (99.99%) with a mass ratio of about 1:4 were used as the source, and pieces of Si (111) wafer covered with 400-500 nm 3C-SiC epilayer were used as the substrates. The products were analyzed by x-ray diffraction, field emission scanning electron microscopy, high-resolution transmission electron microscopy, selected area electron diffraction, Raman spectroscopy, and photoluminescence measurements. Our results show that the as-synthesized GaN pyramids are perfect single crystal with wurtzite structure, which may have potential applications in electronic/photonic devices.

Characteristics of patients suffering from tuberculous pleuritis with pleural effusion culture positive and negative for Mycobacterium tuberculosis, and risk factors for fatality

SETTING

A 2500-bed hospital.

OBJECTIVES

To clarify characteristics of tuberculous pleuritis (TP) with pleural effusion culture positive and negative for Mycobacterium tuberculosis (PECP-MT and PECN-MT) and to identify risk factors for fatality.

PATIENTS AND METHODS

Retrospective analysis of TP patients with PECP-MT and PECN-MT, and review of medical charts of deceased patients.

RESULTS

Of 126 patients enrolled (28 PECP-MT and 98 PECN-MT), those with PECP-MT had a higher prevalence of steroid use (SU) (14.3% vs. 2.0%; P = 0.022) and concurrent tuberculosis involving another site (7.2% vs. 0.0%; P = 0.048), increased neutrophils (36.4% vs. 16.6%; P = 0.020) and decreased glucose levels (mean 88.7 vs. 127.6 g/dl; P = 0.012) in pleural effusion, and a higher fatality rate (28.0% vs. 3.1%; P < 0.001). Deceased patients (n = 10) were older (mean 74.2 vs. 64.4 years; P = 0.047), had a higher incidence of acute renal failure (ARF) (50.0% vs. 11.7%; P = 0.007), and a higher prevalence of malignancy (40.0% vs. 6.3%; P = 0.006), history of stroke (30.0% vs. 7.2%; P = 0.048) and SU (20.0% vs. 1.8%; P = 0.034).

CONCLUSION

SU, concurrent tuberculosis involving another site, increased neutrophils and decreased glucose levels in pleural effusion may be predictive factors for PECP-MT. Malignancy, ARF and SU, and perhaps being elderly or history of stroke, are risk factors for fatality in patients with TP.

[Rapid identification of human testis spermatocyte apoptosis-related gene, TSARG2, by nested PCR and draft human genome searching]

Cloning apoptosis-related novel genes is a key to further understanding of apoptosis mechanism and the biology process of germ cells, and is of momentous significance on clarifying physiological and pathological process of spermatogenesis. To rapidly attain human novel gene full-length cDNA sequence, the gene-specific primers and the vector-specific primers were designed for nested PCR, and draft human genome searching was performed to rapidly identify the TSARG2 (GenBank accession number AY040204) 5' end from a human testis cDNA library, by using a cDNA fragment (GenBank accession number BE644542) as an electronic probe, which was significantly changed in cryptorchidism and represented a novel gene. Furthermore, a mouse homologue of this gene was identified (GenBank accession number AF395083) by lab on-line. TSARG2 with a 1 233 bp length was composed of 6 exons and spanned about 115 kb of genomic DNA, The putative protein encoded by this gene was 305 amino acid with a theoretical molecular weight of 34 751 dalton and did not share significant homology with any known protein in databases. TSARG2 was expressed in many tissues and mapped to chromosome 4q33-34.1 by database analyses. Therefore, we propose that nested-PCR and draft human genome searching are rapid, sensitive, accurate and efficient method for isolating gene 5' end, even full-length gene from cDNA library.

Renal effects of nitric oxide in endotoxemia

Nitric oxide (NO) is postulated to play a key role in the pathophysiology of renal failure in sepsis. Whether the renal effects of increased NO are beneficial or harmful remains unclear. In a porcine model of lipopolysaccharide (LPS)-induced shock, we evaluated the effect of LPS on glomerular filtration rate (GFR) and renal blood flow (RBF). We then administered the nonselective nitric oxide synthase (NOS) inhibitor N(G)-L-arginine methyl ester (L-NAME), and compared its effects on GFR and RBF with those of S-methylisothiourea (SMT), a selective NOS inhibitor, and those of saline. We postulated that SMT, by maintaining constitutive NO, would be more beneficial than either L-NAME or saline. LPS infusion decreased mean arterial pressure (MAP), and increased cardiac output, RBF, and medullary NO content. The increased RBF was diverted to the medulla. There was no evidence of renal dysfunction in the saline-resuscitated group. Both NOS inhibitors increased MAP but decreased RBF, but only L-NAME reduced GFR and increased sodium excretion and renal oxygen extraction. We conclude that NO in endotoxemia is beneficial because it maintains RBF and GFR. Additionally, selective NOS inhibition did not offer any advantages over saline resuscitation.

Lipopolysaccharide regulates constitutive and inducible transcription factor activities differentially in vivo in the rat

The pathophysiology of septic shock is characterized by the induction of multiple proinflammatory genes and their products. Transcription factors play key roles in the transcription of these genes. Transcription factors may play important roles in the pathophysiology of septic shock. However, little information is available regarding the in vivo transcription factor activities during sepsis. We have studied the in vivo effects of LPS on the DNA binding activities of transcription factors Sp1 (promoter selective transcription factor), AP-2 (activating protein-2), AP-1 (activating protein-1), NF-kappaB (nuclear factor kappa B), and CREB (cAMP response element binding protein). We found that LPS up-regulated the DNA binding activity of inducible transcription factors AP-1, NF-kappaB, and CREB in a time-dependent manner, but down-regulated the DNA binding activity of constitutive transcription factors Sp1 and AP-2. Thus, LPS regulates the inducible and constitutive transcription factors differentially under in vivo conditions.

Structure and topology of a peptide segment of the 6th transmembrane domain of the Saccharomyces cerevisae alpha-factor receptor in phospholipid bilayers

A detailed analysis of the structure of an 18-residue peptide AQSLLVPSIIFILAYSLK [M6(252-269, C252A)] in 1,2-dimyristoyl-sn-glycero-phosphocholine bilayers was carried out using solid state NMR and attenuated total reflection Fourier transform infrared spectroscopy. The peptide corresponds to a portion of the 6th transmembrane domain of the alpha-factor receptor of Saccharomyces cerevisiae. Ten homologs of M6(252-269, C252A) were synthesized in which individual residues were labeled with (15)N. One- and two-dimensional solid state NMR experiments were used to determine the chemical shifts and (1)H-(15)N dipolar coupling constants for the (15)N-labeled peptides in oriented dimyristoylphosphatidylcholine bilayers on stacked glass plates. These parameters were used to calculate the structure and orientation of M6(252-269, C252A) in the bilayers. The results indicate that the carboxyl terminal residues (9-14) are alpha-helical and oriented with an angle of about 8 degrees with respect to the bilayer normal. Independently, an attenuated total reflection Fourier transform infrared spectroscopy analysis on M6(252-269, C252A) in a 1,2-dimyristoyl-sn-glycero-phosphocholine bilayer concluded that the helix tilt angle was about 12.5 degrees. The results on the structure of M6(252-269, C252A) in bilayers are in good agreement with the structure determined in trifluoroethanol/water solutions (B. Arshava et al. Biopolymers, 1998, Vol. 46, pp. 343-357). The present study shows that solid state NMR spectroscopy can provide high resolution information on the structure of transmembrane domains of a G protein-coupled receptor.

Investigation of protein-styrene oxide adducts as a molecular biomarker of human exposed to styrene

Hemoglobin-styrene oxide adducts in blood have been studied as a molecular biomarker of worker exposed to styrene. Determination of protein-styrene oxide adducts in different biological samples with modified Raney-Ni procedure is described in this paper. The following biological samples have been investigated: fresh rat blood reacted with styrene oxide in vitro; rat blood reacted with styrene or styrene oxide in vivo; vein blood from workers exposed to styrene in two factories. The data showed that there was a good linear dose-response relationship between reacting dose of styrene oxide or styrene and amount of protein-styrene oxide adducts in both in vitro and in vivo experiments. For human samples, a dose-response relationship between protein adducts and styrene exposure can be found in glass fiber factory, but not in piano manufacture plant.

[Research of cryosurgery in the treatment of maxillo-facial deepish hemangioma]

OBJECTIVE

To observe the effect of cryosurgery on maxillofacial deepish hemangioma, and the facial nerve recovery.

METHODS

Twelve hemangioma patients were observed for the effect of cryosurgery on hemangiomaa in maxillo-facial deepish expose lesion after flapping and four rabbits were used for the observation of the recovery of the facial nerve after cryosurgery.

RESULTS

The facial nerve function of rabbits recovered within six to eight weeks, the twelve hemangioma patients'-facial nerve also recovered with six to eight weeks, only one reoccured in five years.

CONCLUSIONS

Cryosurgery after flapping is an effective; little-traumatic, recover-quickly and spreadingworth method for treatment of maxillo-facial deepish hemangioma.

Preparation and characterization of hCG-loaded polylactide or poly(lactide-co-glycolide) microspheres using a modified water-in-oil-in-water (w/o/w) emulsion solvent evaporation technique

A modified w/o/w emulsion solvent evaporation technique was adopted to prepare human Chorionic Gonadotropin (hCG)-loaded polylactide (PLA) or poly(lactide-co-glycolide) (PLGA) microspheres. The effects of preparative parameters, such as stirring rate, polymer MW and concentration, and the composition of both the inner aqueous phase and oil phase etc., on hCG entrapment efficiency and microsphere characteristics were investigated. It was found that by adding 20% glycerol into the inner aqueous phase and 40% acetone into the oil phase, smooth microspheres approximately 1 microm in diameter could be produced with high hCG entrapment efficiency (>90%). In vitro release test showed a burst release of hCG from PLGA (75:25) microspheres, followed by sustained release of 55% hCG over 2 months. The initial hCG burst from PLGA microspheres increased with the glycerol concentration in the inner aqueous phase, but decreased to a low value (ca. 20%) with the addition of acetone into the oil phase, which could be attributed to the associated changes in surface morphology of the microspheres. In vivo experiments demonstrated that a single shot of hCG-loaded PLGA microspheres could produce a comparable antibody response with the inoculation of free hCG four times.

Synthesis and biophysical analysis of transmembrane domains of a Saccharomyces cerevisiae G protein-coupled receptor

The Ste2p receptor for alpha-factor, a tridecapeptide mating pheromone of the yeast Saccharomyces cerevisiae, belongs to the G protein-coupled family of receptors. In this paper we report on the synthesis of peptides corresponding to five of the seven transmembrane domains (M1-M5) and two homologues of the sixth transmembrane domain corresponding to the wild-type sequence and a mutant sequence found in a constitutively active receptor. The secondary structures of all new transmembrane peptides and previously synthesized peptides corresponding to domains 6 and 7 were assessed using a detailed CD analysis in trifluoroethanol, trifluoroethanol-water mixtures, sodium dodecyl sulfate micelles, and dimyristoyl phosphatidyl choline bilayers. Tryptophan fluorescence quenching experiments were used to assess the penetration of the membrane peptides into lipid bilayers. All peptides were predominantly (40-80%) helical in trifluoroethanol and most trifluoroethanol-water mixtures. In contrast, two of the peptides M3-35 (KKKNIIQVLLVASIETSLVFQIKVIFTGDNFKKKG) and M6-31 (KQFDSFHILLINleSAQSLLVPSIIFILAYSLK) formed stable beta-sheet structures in both sodium dodecyl sulfate micelles and DMPC bilayers. Polyacrylamide gel electrophoresis showed that these two peptides formed high molecular aggregates in the presence of SDS whereas all other peptides moved as monomeric species. The peptide (KKKFDSFHILLIMSAQSLLVLSIIFILAYSLKKKS) corresponding to the sequence in the constitutive mutant was predominantly helical under a variety of conditions, whereas the homologous wild-type sequence (KKKFDSFHILLIMSAQSLLVPSIIFILAYSLKKKS) retained a tendency to form beta-structures. These results demonstrate a connection between a conformational shift in secondary structure, as detected by biophysical techniques, and receptor function. The aggregation of particular transmembrane domains may also reflect a tendency for intermolecular interactions that occur in the membrane environment facilitating formation of receptor dimers or multimers.

The role of cellular trace elements in oral carcinogenesis induced by 4-nitroquinoline 1-oxide(4NQO)

The aim of this study was to define the changes of cellular trace element concentration during the carcinogenesis process of Wistar rat palatine mucosa squamous epithelial cell induced by 4-nitroquinoline-1-oxide (4NQO). 4NQO was painted three times weekly for nineteen weeks on the palatine mucosae of 28 Wistar rats. Histologically normal, precancerous and squamous epithelial cell carcinoma tissues were obtained, and were studied by electron probe X-ray microanalysis. The measured elements were copper (Cu), zinc (Zn), selenium (Se), and molybdenum (Mo). The results were that both copper and zinc in the cellular nucleus and cytoplasm of the squamous epithelial carcinoma cells were significantly decreased. The concentration of cytoplasmic molybdenum significantly decreased in precancerous cells and significantly increased in squamous epithelial carcinoma cells. Minor changes in the concentration of selenium were observed in the process of normal to precancerous and then to cancerous cells. Cu/Zn increased in squamous epithelial carcinoma cells and Cu/Se and Zn/Se decreased in squamous epithelial carcinoma cells. These results suggest that the changes in intracellular copper, zinc, molybdenum are distinctly related to experimental oral carcinogenesis.

[Examination and significance of ABR in non-deafness tinnitus patients]

OBJECTIVE

Research on examination and significance of the auditory brain stem response (ABR) in non-hearing loss tinnitus patients.

METHOD

Recording from forehead-mastoid comparing ABR of non-hearing loss tinnitus patients with normal hearing youths.

RESULT

In the tinnitus patients, the prolongate latency percentage of wave I was 51.6%; the wave III was 20.9%; wave V was 17.9%.

CONCLUSION

Although hearing-loss was not founded in the patients, but the cochlea of some patients had been damaged.

Inhibition of NF-kappaB activation by pyrrolidine dithiocarbamate prevents In vivo expression of proinflammatory genes

Background-The inability to inhibit multiple mediators of septic shock represents a major hurdle in the treatment of septic shock. In vivo inhibition of nuclear factor (NF)-kappaB activation, a transcription factor regulating expression of many proinflammatory genes, could provide a useful strategy for the treatment of septic shock. Methods and Results-In rats challenged with lipopolysaccharide (LPS) 8 mg/kg IV, we determined the time course of NF-kappaB activation and expression of multiple inflammatory signals: tumor necrosis factor-alpha (TNF-alpha), cyclooxygenase-2 (COX-2), cytokine-inducible neutrophil chemoattractant (CINC), and intercellular adhesion molecule-1 (ICAM)-1. We studied the effects of in vivo inhibition of NF-kappaB activation using pyrrolidine dithiocarbamate (PDTC) on the expression of these mediators. NF-kappaB activation preceded the induction of TNF-alpha, COX-2, CINC, and ICAM-1 mRNAs. PDTC prevented the LPS-induced NF-kappaB activation but did not inhibit activation of the transcription factors AP-1, Sp-1, and CREB. PDTC inhibited the LPS-induced expression of TNF-alpha, COX-2, CINC, and ICAM-1 mRNA and proteins and reduced the LPS-induced increases in plasma TNF-alpha, 6-keto-prostaglandin F(1alpha), and CINC concentrations. Inhibition of expression of these mediators prevented the increases in myeloperoxidase activity (a measure of neutrophil sequestration) in the heart, lungs, and liver. Conclusions-NF-kappaB activation correlates with LPS-induced expression of TNF-alpha, COX-2, CINC, and ICAM-1 genes in vivo. PDTC inhibits NF-kappaB activation and expression of these proinflammatory genes and their products. Thus, blocking NF-kappaB activation may be an effective strategy in the treatment of septic shock.

Pyrrolidine dithiocarbamate prevents I-kappaB degradation and reduces microvascular injury induced by lipopolysaccharide in multiple organs

Lipopolysaccharide (LPS) is a key mediator of multiple organ injury observed in septic shock. The mechanisms responsible for LPS-induced multiple organ injury remain obscure. In the present study, we tested the hypothesis that the LPS-induced injury occurs through activation of the transcription factor, nuclear factor-kappaB (NF-kappaB). We examined the effects of inhibiting NF-kappaB activation in vivo in the rat on LPS-induced: 1) gene and protein expression of the cytokine-inducible neutrophil chemoattractant (CINC) and intercellular adhesion molecule-1 (ICAM-1); b) neutrophil influx into lungs, heart, and liver; and c) increase in microvascular permeability induced by LPS in these organs. LPS (8 mg/kg, i.v.) challenge of rats activated NF-kappaB and induced CINC and ICAM-1 mRNA and protein expression. Pretreatment of rats with pyrrolidine dithiocarbamate (50, 100, and 200 mg/kg, i.p.), an inhibitor of NF-kappaB activation, prevented LPS-induced I-kappaBalpha degradation and the resultant NF-kappaB activation and inhibited, in a dose-related manner, the LPS-induced CINC and ICAM-1 mRNA and protein expression. Pyrrolidine dithiocarbamate also markedly reduced the LPS-induced tissue myeloperoxidase activity (an indicator of tissue neutrophil retention) and the LPS-induced increase in microvascular permeability in these organs. These results demonstrate that NF-kappaB activation is an important in vivo mechanism mediating LPS-induced CINC and ICAM-1 expression, as well as neutrophil recruitment, and the subsequent organ injury. Thus, inhibition of NF-kappaB activation may be an important strategy for the treatment of sepsis-induced multiple organ injury.

Structure of segments of a G protein-coupled receptor: CD and NMR analysis of the Saccharomyces cerevisiae tridecapeptide pheromone receptor

Peptides representing both loop and the sixth transmembrane regions of the alpha-factor receptor of Saccharomyces cerevisiae were synthesized by solid-phase procedures and purified to near homogeneity. CD, nmr, and modeling analysis indicated that in aqueous media the first extracellular loop peptide E1(107-125), the third intracellular loop peptide I3(231-243), and the carboxyl terminus peptide I4(350-372) were mostly disordered. In contrast, the second extracellular loop peptide E2(191-206) assumed a well-defined structure in aqueous medium and the sixth transmembrane domain peptide receptor M6(252-269, C252A) was highly helical in trifluoroethanol/water (4:1), exhibiting a kink at Pro258. A synthetic peptide containing a sequence similar to that of the sixth transmembrane domain of a constitutively active alpha-factor receptor M6(252-269, C252A, P258L) in which Leu replaces Pro258 exhibited significantly different biophysical properties than the wild-type sequence. In particular, this peptide had very low solubility and gave CD resembling that of a beta-sheet structure in hexafluoroacetone/water (1:1) whereas the wild-type peptide was partially helical under identical conditions. These results would be consistent with the hypothesis that the constitutive activity of the mutant receptor is linked to a conformational change in the sixth transmembrane domain. The study of the receptor segments also indicate that peptides corresponding to loops of the alpha-factor receptor do not appear to assume turn structures.

The role of endogenous nitric oxide in modulating ischemia-reperfusion injury in the isolated, blood-perfused rat lung

Ischemia-reperfusion (IR) lung injury occurs after various clinical procedures, including cardiopulmonary bypass. It is not clear whether endogenous nitric oxide (NO) is protective or injurious in lungs subjected to IR. Thus, in this study we examined the contribution of endogenous NO to IR injury in isolated, blood-perfused rat lungs. Lungs of male Wistar rats (300 g) were subjected to 30 min ischemia and 180 min reperfusion (I30R180). Lungs were sampled for inducible nitric oxide synthase (i-NOS) mRNA expression (each n = 3) and NOS enzyme activity (each n = 4) at different time points. NOS inhibitors NG-nitro-L-arginine-methyl ester (10[-4] M) and aminoguanidine (10[-4] M) were used to study the contribution of NO to IR injury in lungs subjected to I30R30 and I30R180. The contribution of i-NOS to IR lung injury was studied by inducing i-NOS enzyme with Salmonella lipopolysaccharide, followed by I30R30. We found that ischemia-reperfusion alone can upregulate i-NOS mRNA and i-NOS enzyme activity (p < 0.05, ANOVA), but downregulate constitutive NOS enzyme activity over 180 min reperfusion. Endogenously produced NO is protective against lung injury in I30R180 in normal rats and lung injury in I30R30 in septic rats. NO is also pivotal in maintaining pulmonary vascular homeostasis in septic rat lungs undergoing IR.

Quantitative fluorescence image analysis of DNA content and nuclear morphology on esophageal balloon cytology smears and subsequent development of esophageal and gastric cardia cancer in Linxian, China

The highest incidences of esophageal and gastric cardia cancer in the world occur in northern China. Chinese scientists have developed esophageal balloon cytology screening to detect these cancers, but traditional cytology is sometimes inadequate to find some early, curable lesions. Several studies suggest that quantitative fluorescence image analysis (QFIA) of DNA ploidy and nuclear morphology may be able to improve upon traditional cytology results. In October 1987, esophageal balloon cytology was performed on 1331 adults in Linxian, China, and all samples were evaluated both by traditional cytology and QFIA. From 1987 to May 1991, 62 new squamous esophageal cancers and 44 new adenocarcinomas of the cardia were identified in this cohort. Proportional hazards models were used to evaluate the relationship of cytological diagnoses and six QFIA variables to subsequent cancer risk. These models showed significant trends for increasing esophageal cancer risk, with increasing values in five of the QFIA variables and with increasing severity of the traditional cytological diagnoses. A comparison of models with only cytology variables versus models with both cytology and QFIA variables indicated that the QFIA provided an important additional predictive value. Persons with both cytological dysplasia and high cellular DNA were 8 times more likely to develop esophageal cancer than were individuals with neither of these conditions. For cardia cancer, associations between QFIA variables or cytological diagnoses and later cancer were more limited. This study suggests that the QFIA variables evaluated here are independent predictors of squamous esophageal cancer and that combining QFIA with traditional cytology can improve prediction of esophageal cancer risk.

Cytologic detection of esophageal squamous cell carcinoma and precursor lesions using balloon and sponge samplers in asymptomatic adults in Linxian, China

BACKGROUND

The principal reason for the poor prognosis of esophageal carcinoma is that most tumors are asymptomatic and go undetected until they are unresectable. Previous studies have shown that cytologic screening of asymptomatic high risk individuals can detect curable esophageal carcinomas and precursor lesions, but the sensitivity of such screening is not well documented. The current study evaluated the sensitivity and specificity of currently available balloon and sponge cytologic samplers for detecting biopsy-proven squamous dysplasia and carcinoma in asymptomatic individuals from a high risk population in Linxian, China.

METHODS

Asymptomatic adults were examined with both balloon and sponge samplers, in random order, followed by endoscopy with mucosal iodine staining and biopsy of all unstained lesions. The cytology slides were interpreted using the criteria of the Bethesda System. The balloon and sponge cytologic diagnoses (test) were compared with the biopsy diagnosis (truth) in each patient to estimate the sensitivity and specificity of each sampler.

RESULTS

Of the 439 patients with adequate biopsies, 123 (28%) had histologic squamous dysplasia and 16 (4%) had an invasive squamous carcinoma. The sensitivities/specificities of the balloon and sponge were 44%/99% and 18%/100%, respectively, for detecting biopsy-proven squamous cell carcinoma, and 47%/81% and 24%/92%, respectively, for identifying squamous dysplasia or carcinoma.

CONCLUSIONS

In this study, the balloon sampler was more sensitive than the sponge sampler for detecting esophageal squamous disease, but both techniques were less than optimal. Improved samplers and/or cytologic criteria should increase the sensitivities observed in this baseline study.

Cytologic detection of esophageal squamous cell carcinoma and precursor lesions using balloon and sponge samplers in asymptomatic adults in Linxian, China

BACKGROUND

The principal reason for the poor prognosis of esophageal carcinoma is that most tumors are asymptomatic and go undetected until they are unresectable. Previous studies have shown that cytologic screening of asymptomatic high risk individuals can detect curable esophageal carcinomas and precursor lesions, but the sensitivity of such screening is not well documented. The current study evaluated the sensitivity and specificity of currently available balloon and sponge cytologic samplers for detecting biopsy-proven squamous dysplasia and carcinoma in asymptomatic individuals from a high risk population in Linxian, China.

METHODS

Asymptomatic adults were examined with both balloon and sponge samplers, in random order, followed by endoscopy with mucosal iodine staining and biopsy of all unstained lesions. The cytology slides were interpreted using the criteria of the Bethesda System. The balloon and sponge cytologic diagnoses (test) were compared with the biopsy diagnosis (truth) in each patient to estimate the sensitivity and specificity of each sampler.

RESULTS

Of the 439 patients with adequate biopsies, 123 (28%) had histologic squamous dysplasia and 16 (4%) had an invasive squamous carcinoma. The sensitivities/specificities of the balloon and sponge were 44%/99% and 18%/100%, respectively, for detecting biopsy-proven squamous cell carcinoma, and 47%/81% and 24%/92%, respectively, for identifying squamous dysplasia or carcinoma.

CONCLUSIONS

In this study, the balloon sampler was more sensitive than the sponge sampler for detecting esophageal squamous disease, but both techniques were less than optimal. Improved samplers and/or cytologic criteria should increase the sensitivities observed in this baseline study.

Cytologic detection of esophageal squamous cell carcinoma and precursor lesions using balloon and sponge samplers in asymptomatic adults in Linxian, China

BACKGROUND

The principal reason for the poor prognosis of esophageal carcinoma is that most tumors are asymptomatic and go undetected until they are unresectable. Previous studies have shown that cytologic screening of asymptomatic high risk individuals can detect curable esophageal carcinomas and precursor lesions, but the sensitivity of such screening is not well documented. The current study evaluated the sensitivity and specificity of currently available balloon and sponge cytologic samplers for detecting biopsy-proven squamous dysplasia and carcinoma in asymptomatic individuals from a high risk population in Linxian, China.

METHODS

Asymptomatic adults were examined with both balloon and sponge samplers, in random order, followed by endoscopy with mucosal iodine staining and biopsy of all unstained lesions. The cytology slides were interpreted using the criteria of the Bethesda System. The balloon and sponge cytologic diagnoses (test) were compared with the biopsy diagnosis (truth) in each patient to estimate the sensitivity and specificity of each sampler.

RESULTS

Of the 439 patients with adequate biopsies, 123 (28%) had histologic squamous dysplasia and 16 (4%) had an invasive squamous carcinoma. The sensitivities/specificities of the balloon and sponge were 44%/99% and 18%/100%, respectively, for detecting biopsy-proven squamous cell carcinoma, and 47%/81% and 24%/92%, respectively, for identifying squamous dysplasia or carcinoma.

CONCLUSIONS

In this study, the balloon sampler was more sensitive than the sponge sampler for detecting esophageal squamous disease, but both techniques were less than optimal. Improved samplers and/or cytologic criteria should increase the sensitivities observed in this baseline study.

In vivo inhibition of nuclear factor-kappa B activation prevents inducible nitric oxide synthase expression and systemic hypotension in a rat model of septic shock

We determined the in vivo function of LPS-induced nuclear factor-kappa B (NF-kappa B) activation in mediating inducible nitric oxide synthase (iNOS) mRNA and protein expression, and systemic arterial hypotension in a rat model of septic shock. LPS (8 mg/kg i.v.) challenge of rats activated NF-kappa B within 15 min in lung tissue, and the response persisted up to 4 h. NF-kappa B activation preceded the induction of iNOS mRNA. Pyrrolidine dithiocarbamate (PDTC), an inhibitor of NF-kappa B effective in cellular studies, prevented NF-kappa B activation in vivo and reduced iNOS mRNA expression and the increase in iNOS activity activated by LPS. At PDTC concentrations of 50, 100, and 200 mg/kg, the reductions of iNOS mRNA were 20, 46, and 48%, and the reductions in iNOS activity were 59, 66, and 75%, respectively. The PDTC concentration-dependent reductions in iNOS activity produced similar decreases in plasma nitrite/nitrate concentrations. PDTC also prevented the decrease in arterial blood pressure induced by LPS. These results demonstrate that activation of NF-kappa B is a critical in vivo regulatory mechanism mediating LPS-induced iNOS expression and the resultant systemic hypotension.

In vivo inhibition of nuclear factor-kappa B activation prevents inducible nitric oxide synthase expression and systemic hypotension in a rat model of septic shock

We determined the in vivo function of LPS-induced nuclear factor-kappa B (NF-kappa B) activation in mediating inducible nitric oxide synthase (iNOS) mRNA and protein expression, and systemic arterial hypotension in a rat model of septic shock. LPS (8 mg/kg i.v.) challenge of rats activated NF-kappa B within 15 min in lung tissue, and the response persisted up to 4 h. NF-kappa B activation preceded the induction of iNOS mRNA. Pyrrolidine dithiocarbamate (PDTC), an inhibitor of NF-kappa B effective in cellular studies, prevented NF-kappa B activation in vivo and reduced iNOS mRNA expression and the increase in iNOS activity activated by LPS. At PDTC concentrations of 50, 100, and 200 mg/kg, the reductions of iNOS mRNA were 20, 46, and 48%, and the reductions in iNOS activity were 59, 66, and 75%, respectively. The PDTC concentration-dependent reductions in iNOS activity produced similar decreases in plasma nitrite/nitrate concentrations. PDTC also prevented the decrease in arterial blood pressure induced by LPS. These results demonstrate that activation of NF-kappa B is a critical in vivo regulatory mechanism mediating LPS-induced iNOS expression and the resultant systemic hypotension.

Inducible nitric oxide synthase after sensitization and allergen challenge of Brown Norway rat lung

1. We studied the effects of ovalbumin (OA) sensitization and challenge on inducible nitric oxide synthase (iNOS) gene and protein expression in Brown-Norway rats in vivo. 2. By use of Northern analysis, a 4.4-kb iNOS mRNA transcript was weakly observed in control rat lung but there was a 3 fold increase in lungs sensitized to OA alone (P<0.05). In sensitized rats, four hours after exposure to OA aerosol, there was a 6 fold increase in iNOS mRNA transcript (P<0.05), which returned to baseline at 24 h. 3. Immunostaining with an anti-mouse iNOS antibody revealed some patchy staining of airway epithelium in naive rats. There were no changes in sensitized rats exposed to saline, but sensitized and OA-exposed rats showed increased expression in iNOS staining in macrophages. 4. Electrophoretic mobility shift assays of lung nuclear extracts showed a marked increase in nuclear factor-kappaB (NF-kappaB)-binding activity at 2 h after allergen exposure with return to baseline at 6, 12 and 24 h. 5. We concluded that there is increased iNOS gene and protein expression associated with increased NF-kappaB DNA-binding in lungs of sensitized and challenged rats. The increase in iNOS expression may underlie the increase in exhaled NO found after allergen challenge and may contribute to the development of allergen-induced airway hyperresponsiveness.

Alternate COX-2 transcripts are differentially regulated: implications for post-transcriptional control

Prostaglandin (PG) synthesis during inflammation occurs mainly via the transcriptionally regulated cyclooxygenase, COX-2. In pulmonary type II A549 cells, Northern analysis identified multiple IL-1 beta-inducible COX-2 mRNA transcripts. Amplification of 3'-cDNA ends by anchored PCR revealed products corresponding to the predominant 4.5 and 2.7 kb transcripts. Sequence analysis of amplification products indicated that these transcripts arose by alternate consensus and non-consensus polyadenylation site usage. The predominant 4.5 kb transcript showed a half-life in excess of two hours that was further stabilized by IL-1 beta. In addition, the COX-2 3'-untranslated region (UTR), which contains 22 copies of the putative RNA instability motif, AUUUA, when cloned downstream of a constitutively expressed luciferase gene, was found to confer partial IL-1 beta responsiveness in LA-4 cells. Finally, in vivo in LPS-treated rats, differential expression of similar COX-2 mRNA isoforms was also observed. Taken together these data suggest a functional role for post-transcriptional mechanisms, including alternate polyadenylation, in the control of COX-2.

Time course and cellular localization of lipopolysaccharide-induced inducible nitric oxide synthase messenger RNA expression in the rat in vivo

OBJECTIVES

The role of nitric oxide in mediating the early phase of hypotension and cardiovascular hyporeactivity in sepsis, and the cellular sources of inducible nitric oxide synthase expression under in vivo conditions, remain unclear. The objective of this study was to elucidate the time course and cellular location of inducible nitric oxide synthase messenger RNA (mRNA) expression in rats treated with lipopolysaccharide in vivo.

DESIGN

Prospective, placebo-controlled, laboratory study.

SETTING

Experimental laboratory of a postgraduate medical research institution.

SUBJECTS

Normal, anesthetized rats.

INTERVENTIONS

Animals were treated with lipopolysaccharide (15 mg/kg i.p.), saline (1 mL/kg i.p.), or lipopolysaccharide plus dexamethasone (3 mg/kg i.p., 50 mins before lipopolysaccharide administration) in vivo 4 hrs before the removal of tissues.

MEASUREMENTS AND MAIN RESULTS

Total RNA and mRNA were extracted. Total RNA was used for reverse transcription polymerase chain reaction. Poly-(A)+ mRNA was isolated for Northern blot analysis. Cryostat sections of heart and lung were prepared for in situ hybridization to elucidate the cellular location of the inducible nitric oxide synthase gene. Hearts, lungs, aortae, and pulmonary arteries from lipopolysaccharide-treated animals expressed inducible nitric oxide synthase mRNA, which was markedly inhibited by pretreatment with dexamethasone (except in aorta). The threshold time point for inducible nitric oxide synthase mRNA induction was between 20 and 40 mins after lipopolysaccharide administration. The quantity of mRNA increased progressively thereafter, reaching a plateau between 4 and 8 hrs and decreasing markedly by 24 hrs. These findings are consistent with the time course of lipopolysaccharide-induced hypotension and cardiovascular hyporeactivity in animal models of septic shock and in man. Inducible nitric oxide synthase mRNA was mainly detected in vascular and airway smooth muscle cells, cardiac myocytes, pneumocytes, and infiltrated inflammatory cells, but was also identified in airway epithelial and vascular endothelial cells. Vascular smooth muscle represented the predominant cell type expressing inducible nitric oxide synthase under these conditions.

CONCLUSIONS

These results provide further molecular evidence for the involvement of nitric oxide in the early phase of hypotension and cardiovascular hyporeactivity seen in septic shock. They also suggest that nitric oxide derived from vascular smooth muscle cells may contribute significantly to this hypotension and cardiovascular reactivity.

Studies of esophageal balloon cytology in Linxian, China

Esophageal cancer is the second leading cause of cancer death in China. Esophageal cancer has a very poor prognosis, principally because most tumors are asymptomatic until they are unresectable. Esophageal balloon cytology is an early detection method developed by Chinese scientists to identify resectable early cancers and precursor lesions. Previous studies have reported high sensitivities for detecting esophageal cancer in symptomatic patients. The current report describes several studies evaluating this diagnostic technique in asymptomatic individuals. A comparison of Chinese and U. S. cytological diagnoses of the same esophageal samples showed that the Chinese categories of precancerous neoplasia were more inclusive than the corresponding U. S. categories. Comparisons of both Chinese and U. S. cytological diagnoses with concurrent histological findings showed low (14-36%) sensitivities for the cytological detection of biopsy-proven cancers. Prospective follow-up studies of several screened cohorts showed a consistent progression of risk for developing esophageal cancer with increasing severity of initial cytological diagnosis. These preliminary studies suggest that esophageal balloon cytology is a useful technique that can benefit from additional research to improve its optimal performance.

Differential regulation of the constitutive and inducible nitric oxide synthase mRNA by lipopolysaccharide treatment in vivo in the rat

OBJECTIVE

Endotoxin and cytokines have been reported to have both stimulatory and inhibitory effects on endothelial cell-derived nitric oxide release. The discrepancy may be explained by differential regulation of the endothelial and inducible type of nitric oxide synthase gene expression. This study aimed to investigate the differential effect of lipopolysaccharide treatment in vivo on the three isoforms (endothelial, brain-type, and inducible) of nitric oxide synthase gene expression in the rat.

DESIGN

Prospective, controlled, animal trial.

SETTING

Experimental laboratory of a postgraduate medical research institution.

SUBJECTS

Normal, anesthetized rats.

INTERVENTIONS

Animals were treated with lipopolysaccharide (15 mg/kg iP), saline (1 mL/kg ip), or lipopolysaccharide plus dexamethasone (3 mg/kg ip, 50 mins before lipopolysaccharide administration) in vivo 4 hrs before experimentation.

MEASUREMENTS AND MAIN RESULTS

The expression of endothelial, brain-type, and inducible nitric oxide synthase mRNAs was quantified by Northern blot analysis using bovine, rat, and mouse cDNA probes, respectively. An endothelial nitric oxide synthase mRNA was detected at 4.3 kilobase in the heart, lung, and aorta, and a 10-kilobase brain-type nitric oxide synthase mRNA was detected in the brain. The endothelial and brain-type signals were strong in tissues from animals treated with saline, but were reduced by three- to four-fold in tissues from lipopolysaccharide-treated rats as estimated by optical density ratio. The 4.4-kilobase inducible nitric oxide synthase mRNA detected using the murine cDNA probe was absent or negligible in the heart, lung, and brain from saline-treated rats, but was markedly increased in the same tissues from lipopolysaccharide-treated animals. Dexamethasone significantly inhibited lipopolysaccharide-induced inducible nitric oxide synthase mRNA expression, but had no effect on the down-regulation of endothelial and brain nitric oxide synthase mRNAs.

CONCLUSIONS

Rats treated with lipopolysaccharide in vivo display down-regulation of endothelial nitric oxide mRNA in the heart, lung, and aorta, and brain-type nitric oxide synthase mRNA in the brain There was a parallel up-regulation of inducible nitric oxide synthase mRNA in all tissues except in the aorta. Dexamethasone prevents the induction of inducible nitric oxide synthase mRNA. but has no effect on the down-regulation of endothelial and brain-type nitric oxide synthase mRNAs induced by lipopolysaccharide. Thus, endotoxin regulates constitutive and inducible nitric oxide synthase mRNA differentially.