[Clinical effect of endoscopic transnasal sphenoidal approach with simple muscle packing for intrasellar arachnoid cyst]

Objective: To examine the clinical effect of simple muscle packing through transnasal sphenoid approach in the treatment of intrasellar arachnoid cyst. Methods: The clinical data of 11 patients with intrasellar arachnoid cyst treated by transnasal sphenoidal approach with simple muscle packing at the Neurosurgery Department of the First Affiliated Hospital of Zhengzhou University from January 2014 to February 2020 were retrospectively analyzed. There were 5 males and 6 females, with a median age of 48 years (range: 23 to 75 years). The clinical manifestations included headache in 6 cases, dizziness in 4 cases, hypo-libido in 1 case, disturbance of consciousness in 1 case, visual impairment in 7 cases and mixed pituitary dysfunction in 5 cases. The enlargement of the sellar fossa was seen in the preoperative MRI images. The enhanced MRI images showed that the cyst wall of the intrasellar arachnoid cyst was not enhanced, and the compression and thinning of the sellar base was seen in the CT images. In 9 cases, the cyst extended suprasellar and the sellar septum was "arched". In 7 cases, the cyst compressed the optic chiasm upward. The cyst walls of all patients were incised through the nasal sphenoid approach under the endoscope, and the muscle was packed after sufficient drainage. The postoperative symptoms, pituitary endocrine function and recurrence of patients were followed up. Results: MRI images of the sellar region in all patients showed significant reduction or disappearance of cysts. Intracranial infection occurred in 1 case and electrolyte disorder in 2 cases, which were relieved after symptomatic treatment. No cerebrospinal fluid rhinorrhea occurred. Postoperative clinical symptoms were completely relieved in 6 cases and partially relieved in 5 cases. Pituitary endocrine function recovered completely in 2 cases and improved significantly in 4 cases. All patients were followed up for 10 to 40 months. One patient found to have a partial recurrence of the cyst 3 months after surgery. Because there were no new symptoms appeared, the follow-up was continued without second operation. Conclusion: Transnasal sphenoidal approach is a feasible method for the treatment of intrasellar arachnoid cyst.

[Correlation between the pre-and post-operative sagittal parameters and the quality of life in patients with degenerative and isthmic spondylolisthesis]

Objective: To assess the relationship between health-related quality of life (HRQOL) and spinal sagittal parameters in patients with degenerative and isthmic spondylolisthesis before and after surgery, and to provide a biomechanical basis for improving the clinical prognosis of such patients. Methods: A retrospective analysis of 63 patients with lumbar spondylolisthesis who received lumbar fusion surgery in the Department of Spine Surgery, Tianjin Union Medical Center from December 2017 to June 2020 was carried out. There were 16 males and 47 females with a mean age of (59±8) years. Subgroup analyses were conducted based on disease type (degenerative lumbar spondylolisthesis (DS) and the isthmic spondylolisthesis (IS)) and HRQOL scores. Patients were evaluated post-operatively to observe the improvement of symptoms and quality of life. The relationship between operative related factors, HRQOL scores before and after surgery, and spino-pelvic sagittal parameters (including sagittal axis of the spine, lumbar lordosis angle, pelvic incidence angle, pelvic tilt angle (PT), sacral tilt angle, matching degree of pelvic incidence angle (PI) and lumbar lordosis angle (LL), lumbar 1 vertebra plumb line, upper lumbar curve, lower lumbar curve) in the two groups were analyzed. The correlation between the improvement of HRQOL scores and spino-pelvic sagittal parameters in the DS group and the IS group was analyzed and compared. Results: There were significant differences between postoperative HRQOL scores compared with those before the operation in both the DS and IS groups at three times of follow-up after the operation (all P<0.05). There was no difference in the last HRQOL score, the number of surgical segments, operation time and intraoperative blood loss between the two groups (all P>0.05). The parameters of PT and PI-LL in DS patients with VAS back pain score>3 and ≤3 were statistically different (13.7°±6.4° vs 26.6°±7.4°, 5.1°±8.2° vs 18.2°±13.1°, respectively, both P<0.05), similar results were obtained in IS patients (14.1°±6.9° vs 16.4°±8.7°, 2.9°±9.7° vs 6.8°±9.8°, respectively, both P<0.05). In addition, the parameters of PT and PI-LL between patients with ODI>20 and ≤20 were all statistically different in the two groups at the last follow-up after surgery (all P<0.05). The improvement of VAS back pain score in DS and IS groups was significantly related to the improvement of PT value, respectively (r=0.76, 0.78, both P<0.05). The PT, LL and PI-LL were significantly correlated with the ODI in the DS group (r=0.60, 0.62, 0.50, all P<0.05). There was also a correlation between the improvement of ODI and PT, LL and PI-LL in the IS group, respectively (r=0.22, 0.41, 0.76, all P<0.05). Conclusions: Certain correlation exists between the HRQOL and spinal sagittal parameters in patients with degenerative and isthmic spondylolisthesis before and after surgery. For the treatment of lumbar spondylolisthesis and improvement of quality of life, the primary goal is to reconstruct the matching degree of the lumbar lordosis angle and PI, and to reduce the PT value to the normal range by tilting the pelvis forward.

miR-140-3p Knockdown Suppresses Cell Proliferation and Fibrogenesis in Hepatic Stellate Cells via PTEN-Mediated AKT/mTOR Signaling

PURPOSE

Liver fibrosis is a major cause of morbidity and mortality and the outcome of various chronic liver diseases. Activation of hepatic stellate cells (HSCs) is the key event in liver fibrosis. Studies have confirmed that miR-140-3p plays a potential regulatory effect on HSC activation. However, whether miR-140-3p mediates the liver fibrosis remains unknown.

MATERIALS AND METHODS

Expression of miR-140-3p was detected by real-time quantitative PCR (qPCR). Cell proliferation was measured by MTT, while cell apoptosis rate was determined via flow cytometry. Western blot assay was used to detect the expression of cleaved PARP. The fibrogenic effect was evaluated by expression of α-smooth muscle actin and desmin. Functional experiments were performed in transforming growth factor β1 (TGF-β1)-induced HSC-T6 cells with transfection of anti-miR-140-3p and/or siPTEN. Target binding between miR-140-3p and PTEN was predicted by the TargetScan database and identified using luciferase reporter assay and RNA immunoprecipitation.

RESULTS

TGF-β1 induced the activation of HSC-T6 cells, and miR-140-3p expression varied according to HSC-T6 cell activation status. Knockdown of miR-140-3p reduced cell proliferation and the expressions of α-SMA and desmin, as well as increased apoptosis, in TGF-β1-induced HSC-T6 cells, which could be blocked by PTEN silencing. Additionally, inactivation of the AKT/mTOR signaling pathway stimulated by miR-140-3p knockdown was abolished when silencing PTEN expression. PTEN was negatively regulated by miR-140-3p via direct binding in HSC-T6 cells.

CONCLUSION

miR-140-3p is an important mediator in HSC-T6 cell activation, and miR-140-3p knockdown suppresses cell proliferation and fibrogenesis in TGF-β1-induced HSC-T6 cells, indicating that miR-140-3p may be a potential novel molecular target for liver fibrosis.

[Clinical characteristics and microsurgical strategy of intracranial posterior circulation aneurysms]

Objective: To explore the clinical characteristics and microsurgical strategies of intracranial posterior circulation aneurysms. Methods: The clinical manifestations, imaging data, surgical approaches and follow-up results of 35 patients with circulating aneurysms (37 aneurysms) treated by microsurgery in the First Affiliated Hospital of Zhengzhou University from January 2013 to January 2018 were analyzed retrospectively. Results: A total of 22 aneurysms were clipped, 13 were clipped and resected, 1 case was clipped and together with AVM resection and 1 case was isolated. Of 37 aneurysms in 35 patients, 11 aneurysms were at the basilar artery apexes, 10 at the posterior cerebral arteries, 6 at the posterior inferior cerebellar arteries, 3 at the basilar arteries, 3 at the vertebral arteries (including 1 case of vertebral arterial dissecting aneurysm), 2 at the anterior inferior cerebellar arteries and 2 at the superior cerebellar arteries. The surgical approaches included pterional approach, extensive pterional approach, infratemporal fossa approach, retrosigmoid approach and far-lateral approach. The Glasgow Outcome Scale (GOS) scores showed good recovery in 24 cases, moderate neurological dysfunction in 6 cases, severe neurological dysfunction in 2 cases, persistent vegetative state in 1 case and 2 cases of death 6 months after their discharge from hospital. Conclusions: Posterior circulation aneurysms are adjacent to important structures. They are deep in position, with small operation space and difficult to operate. Full preoperative evaluation of the condition, selection of appropriate surgical methods are the key factors to benefit the patients.

[Study on the state of Chinese medicine practitioner in the middle and lower classes of Shanghai in the Republic of China: the case of Yao Xinyuan]

During the period of the Republic of China, Shanghai, with its multicultural communities and a chaos medical market, gathered many traditional Chinese medicine practitioners from all over the country. In addition to a few numbers of famous Chinese medicine practitioners, there were a large number of middle and lower class Chinese medicine practitioners who were not famous in the communities at that time, Yao Xinyuan was most representative one. Although the history of their life is hard to find out in detail, we can dig out some fragments of their medical activities, relying on the many publications from that time's Shanghai. After studying the literatures, we found some characteristics. Although they are faced with fierce medical competition, and it was hard to for them in the long-term survival of Shanghai, they still cherish the ambition to make contribution to the country, and strive to carry the traditional Chinese medicine forward by studying the ancient and seeking the new, integrating Chinese and Western medicine.

Differences in expression of serum protein in patients with psoriasis vulgaris and blood heat syndrome and healthy volunteers

To explore the mechanism of psoriasis vulgaris (PV), serum protein expression profiles between PV patients with blood-heat syndrome and healthy volunteers were detected by isobaric tags for relative and absolute quantitation (iTRAQ). First, sera from 15 PV patients with blood-heat syndrome and 10 healthy volunteers were collected; then, serum proteins were separated and hydrolyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and a specific iTRAQ marker enzyme respectively after further purification and protein abundance treatment. Compared with the control group, differentially expressed proteins in PV patients with blood-heat syndrome were identified and analyzed by tandem mass spectrometry. A total of 787 proteins were identified and 718 proteins had a functional annotation with gene ontology (GO) by iTRAQ in the current study. Significant differences (P &lt;0.05) and great differences (P &lt;0.01) were found in 681 proteins and 536 proteins respectively between the patient group and healthy group. ). Different protein expression profiles in serum existed between PV patients with blood-heat syndrome and healthy volunteers; the differences largely involved immune-related proteins and lipoproteins. The proteins specific for PV with blood-heat syndrome deserves further investigation.

Biocompatibility study on Ni-free Ti-based and Zr-based bulk metallic glasses

Safety and reliability are crucial issues for medical instruments and implants. In the past few decays, bulk metallic glasses (BMGs) have drawn attentions due to their superior mechanical properties, good corrosion resistance, antibacterial and good biocompatibility. However, most Zr-based and Ti-based BMGs contain Ni as an important element which is prone to human allergy problem. In this study, the Ni-free Ti-based and Zr-based BMGs, Ti₄₀Zr₁₀Cu₃₆Pd₁₄, and Zr₄₈Cu₃₆Al₈Ag₈, were selected for systematical evaluation of their biocompatibility. Several biocompatibility tests, co-cultural with L929 murine fibroblast cell line, were carried out on these two BMGs, as well as the comparison samples of Ti6Al4V and pure Cu. The results in terms of cellular adhesion, cytotoxicity, and metallic ion release affection reveal that the Ti₄₀Zr₁₀Cu₃₆Pd₁₄ BMG and Ti6Al4V exhibit the optimum biocompatibility; cells still being attached on the petri dish with good adhesion and exhibiting the spindle shape after direct contact test. Furthermore, the Ti₄₀Zr₁₀Cu₃₆Pd₁₄ BMG showed very low Cu ion release level, in agreement with the MTT results. Based on the current findings, it is believed that Ni-free Ti-based BMG can act as an ideal candidate for medical implant.

A comparative study of loratadine syrup and cyproheptadine HCL solution for treating perennial allergic rhinitis in Taiwanese children aged 2-12 years

We assessed the efficacy of loratadine syrup compared with cyproheptadine HCl solution for treating children aged from 2 to 12 years with perennial allergic rhinitis (PAR) in Taiwan. Sixty children with mite-induced PAR were enrolled and randomly placed into two treatment groups: loratadine syrup or cyproheptadine HCl solution. Treatment efficacy and symptom changes from baseline to post-treatment were evaluated by total symptom scores and visual analogue scales (VAS) during a 2-week period. There were no differences in age, gender, height, or weight between the two groups. After 2 weeks of treatment, there was a significantly greater reduction in symptom scores in the loratadine group than in the cyproheptadine group (p&#x003C;0.001). Clinical and subjective VAS showed significant differences in percentage changes from baseline between the loratadine and cyproheptadine groups at all time points (all p&#x003C;0.001, in favor of loratadine). Clinical VAS change at week 1: 95.1 vs 11.3; subjective VAS change at week 1: 88.6 vs 13.6; clinical VAS change at week 2: 125.5 vs 18.3; subjective VAS change at week 2: 101.4 vs 7.1. Thus, loratadine was superior to cyproheptadine for alleviating both nasal and non-nasal symptoms of perennial allergic rhinitis in Taiwanese children aged 2-12 years.

Oxygen vacancy density-dependent transformation from infrared to Raman active vibration mode in SnO2 nanostructures

Raman spectra acquired from spherical, cubic, and cuboid SnO2 nanocrystals (NCs) reveal a morphologically independent Raman mode at ∼302 cm(-1). The frequency of this mode is slightly affected by the NC size, but the intensity increases obviously with decreasing NC size. By considering the dipole changes induced by oxygen vacancies and derivation based on the density functional theory and phonon confinement model, an oxygen vacancy density larger than 6% is shown to be responsible for the transformation of the IR to Raman active vibration mode, and the intensity enhancement is due to strong phonon confinement.

Green light stimulates terahertz emission from mesocrystal microspheres

The discovery of efficient sources of terahertz radiation has been exploited in imaging applications, and developing a nanoscale terahertz source could lead to additional applications. High-frequency mechanical vibrations of charged nanostructures can lead to radiative emission, and vibrations at frequencies of hundreds of kilohertz have been observed from a ZnO nanobelt under the influence of an alternating electric field. Here, we observe mechanical resonance and radiative emission at ∼ 0.36 THz from core-shell ZnO mesocrystal microspheres excited by a continuous green-wavelength laser. We find that ∼ 0.016% of the incident power is converted into terahertz radiation, which corresponds to a quantum efficiency of ∼ 33%, making the ZnO microspheres competitive with existing terahertz-emitting materials. The mechanical resonance and radiation stem from the coherent photo-induced vibration of the hexagonal ZnO nanoplates that make up the microsphere shells. The ZnO microspheres are formed by means of a nonclassical, self-organized crystallization process, and represent a straightforward route to terahertz radiation at the nanoscale.

Longitudinal optical phonon-plasmon coupling in luminescent 3C-SiC nanocrystal films

Glycerol-passivated 3C-SiC nanocrystal (NC) solid films with tunable blue photoluminescence show abnormal longitudinal optical (LO) phonon behavior. As the NC size increases, the LO phonon intensity increases in the Raman spectra of the solid films and is even larger than that of the transverse optical mode. The Raman spectra cannot be fitted by using only the phonon confinement model. When further considering the coupling between the LO phonon and plasmon induced by the surface deformation potential in the glycerol layer, good agreement is achieved between the experiments and theory. This indicates that the coupled LO phonon-plasmon effect arising from the surface bonding structure plays a crucial role in the modified LO phonon behavior.

Crystalline core/shell Si/SiO2 nanotubes formed via interfacial stress imbalance

Crystalline core/shell Si/SiO2 nanotubes (NTs) with outer diameters of 130-220 nm and lengths of approximately 1 microm have been synthesized using thermal evaporation. High resolution scanning electron microscopy reveals that the NT formation stems from the intrinsic interfacial stress imbalance in the strained Si/SiO2 bilayered film, consequently leading to NTs with different orifice levels. The NT diameters depend strongly on the bilayer film thicknesses and crystal orientations of the Si and SiO2 layers. A modified Timoshenko formula is derived to calculate the dependence of the tube diameter on the bilayer film thickness. The obtained results are consistent well with experimental data.

Optimization of selected cultivation parameters for Cordyceps guangdongensis

AIMS

To increase the fruit body production of Cordyceps guangdongensis, selected cultivation conditions, especially nutritional parameters were optimized.

METHODS AND RESULTS

Cordyceps guangdongensis was inoculated on potato dextrose agar slants with pH values from 4.5 to 9.0 and cultivated in artificial media with different carbon and nitrogen supplements. Primordium formation in C. guangdongensis was favoured by slightly acidic conditions. Fruit body yields and biological efficiency (BE) recorded were all highest in cultures of C. guangdongensis supplemented with sucrose and KNO3 as carbon and nitrogen supplements, respectively. Highest fruit body yields and BE values were recorded with C : N ratio of 12 : 1. The optimal medium consisted of (g l(-1)) 20.0 sucrose, 4.0 soya bean powder, 5.0 beef extract and 10.0 KNO3. Cultivation experiments using this medium confirmed its reliability; 18.35% of BE was obtained, compared with a calculated maximum BE of 18.65% based on orthogonal test data.

CONCLUSIONS

Cordyceps guangdongensis preferred sucrose and potassium nitrate as best carbon and nitrogen supplements. It produced satisfying yield of fruit body with optimized medium.

SIGNIFICANCE AND IMPACT OF THE STUDY

Optimized artificial cultivation conditions could promote the yield of C. guangdongensis and decreased the cost of production.

Glycerol-bonded 3C-SiC nanocrystal solid films exhibiting broad and stable violet to blue-green emission

We have produced glycerol-bonded 3C-SiC nanocrystal (NC) films, which when excited by photons of different wavelengths, produce strong and tunable violet to blue-green (360-540 nm) emission as a result of the quantum confinement effects rendered by the 3C-SiC NCs. The emission is so intense that the emission spots are visible to the naked eyes. The light emission is very stable and even after storing in air for more than six months, no intensity degradation can be observed. X-ray photoelectron spectroscopy and absorption fine structure measurements indicate that the Si-terminated NC surfaces are completely bonded to glycerol molecules. Calculations of geometry optimization and electron structures based on the density functional theory for 3C-SiC NCs with attached glycerol molecules show that these molecules are bonded on the NCs causing strong surface structural change, while the isolated levels in the conduction band of the bare 3C-SiC NCs are replaced with quasi-continuous bands that provide continuous tunability of the emitted light by changing the frequencies of exciting laser. As an application, we demonstrate the potential of using 3C-SiC NCs to fabricate full-color emitting solid films by incorporating porous silicon.

Size-independent low-frequency Raman scattering in Ge-nanocrystal-embedded SiO2 films

The peak position and linewidth of the low-frequency Raman mode observed from amorphous silica films embedded with Ge nanocrystals doped with Si show a size-independent behavior. Spectral analysis reveals the formation of a thin amorphous GeSi layer on the surface of the Ge nanocrystal. Theoretical calculation based on a modified three-region model discloses that the acoustic impedance of the interfacial GeSiO layer is responsible for the size-independent behavior. During high-temperature annealing, Ge atoms are segregated from the interface into the core, and the GeSiO interface layer is converted to SiO(2), leading to disappearance of the size-independent vibration mode.

Construction and analysis of cDNA library of Necator americanus third stage larvae

OBJECTIVE

To obtain the genetic information on Necator americanus and to search for the purpose genes.

METHODS

mRNA was isolated from the third stage larvae of Necator americanus maintained in hamsters. Double strand cDNA was synthesized and ligated to lambda ZAPII vector to construct the cDNA library. Expressed sequence tages (ESTs) were obtained by single pass sequencing of randomly isolated cDNA clones from the established library.

RESULTS

A cDNA library of N. americanus was successfully constructed with high recombinant efficiency. The titer of unamplified library was 1 x 10(7). The insert size was about 750-3,000 bp. Of 11 ESTs obtained from the library, 7 have a significant homology with certain functional genes.

CONCLUSION

A high quality and high representative cDNA library of N. americanus was constructed at the first time and some functional genes were identified from the library by ESTs.

Tissue injury following inhalation of fine particulate matter and hydrogen peroxide is associated with altered production of inflammatory mediators and antioxidants by alveolar macrophages

Hydrogen peroxide (H(2)O(2)) is present in the atmosphere at concentrations known to induce cell and tissue damage. However, inhaled H(2)O(2) vapor should not reach the lower lung due to its high water solubility. It has been suggested that hygroscopic components of particulate matter (PM) may transport H(2)O(2) into the lower lung and induce tissue injury and this was investigated. Ammonium sulfate [(NH(4))(2)SO(4)] was selected as a model for fine atmospheric PM. Treatment of female Sprague-Dawley rats with (NH(4))(2)SO(4) (429 or 215 microg/m(3); 0.3-0.4 microm mass median diameter) or H(2)O(2) (10, 20, or 100 ppb) alone or in combination for 2 h had no major effect on bronchoalveolar lavage fluid cell number or viability or on protein content or lactate dehydrogenase levels, either immediately or 24 h after exposure, relative to air-exposed rats. However, electron microscopy revealed increased numbers of neutrophils in pulmonary capillaries adhered to the vascular endothelium in rats treated with the combination of (NH(4))(2)SO(4) + H(2)O(2). Exposure of rats to (NH(4))(2)SO(4) + H(2)O(2) also resulted in tumor necrosis factor-alpha (TNF-alpha) production by alveolar macrophages. This was observed immediately and 24 h after exposure. Immediately after inhalation of (NH(4))(2)SO(4) + H(2)O(2), a transient increase in production of superoxide anion by alveolar macrophages was observed. In contrast, nitric oxide production by cells from rats exposed to (NH(4))(2)SO(4) + H(2)O(2) or H(2)O(2) alone was decreased, and this persisted for 24 h. Decreases in nitric oxide may be due to superoxide anion-driven formation of peroxynitrite. In this regard, nitrotyrosine, an in vivo marker of peroxynitrite, was detected in lung tissue after exposure of rats to (NH(4))(2)SO(4) + H(2)O(2) or H(2)O(2). We also found that expression of the antioxidant enzyme heme oxygenase-1 by stimulated alveolar macrophages was increased following exposure of rats to (NH(4))(2)SO(4) + H(2)O(2). Taken together, these studies demonstrate that the biological effects of inhaled fine PM are augmented by H(2)O(2). Moreover, tissue injury induced by fine PM may be related to altered production of cytotoxic mediators by alveolar macrophages.

Differential stress induction of individual Alu loci: implications for transcription and retrotransposition

While human Alu repeats can be considered to be members of an extremely large, globally regulated, multigene family, each member of this family resides within a different sequence context that might uniquely modulate its transcription. Unique 3' flanking sequences for several transcriptionally active human Alu elements were identified by cDNA cloning and used for primer extension analysis to compare the basal and stress-induced expression of the corresponding Alu loci. Each of six Alu loci investigated exhibits a unique pattern of expression in three different human cell lines and in response to stress induction. The sequence context surrounding each Alu member uniquely determines its transcriptional regulation. In many cases, the individual Alu loci and total Alu RNA exhibit opposing patterns of expression implying that local rather than global regulation ultimately determines the expression of individual members. Some of the stresses, which induce Alu transcription, increase co-expression of LINE1 RNA, another requirement for Alu retrotransposition.

Incidence of gastroesophageal malignancy in patients with dyspepsia in Hong Kong: implications for screening strategies

BACKGROUND

A "test-and-treat" strategy for H pylori infection has been recommended in Europe and North America as safe and cost-effective for management of patients with dyspepsia. The primary aim of this study was to determine the frequency of gastroesophageal cancer in 2 groups of patients with dyspepsia: those 45 years of age or younger without "alarm" symptoms (low-risk group) and patients over 45 years of age or any patient with "alarm" symptoms (high-risk group). A secondary aim was to determine the frequency of gastric cancer among patients in the low-risk group with or without a positive serology for H pylori.

METHODS

Patients with persistent dyspepsia were recruited from 4 regional hospitals in Hong Kong. Those in the low-risk group were evaluated for H pylori by using a whole blood serology test; they underwent endoscopy within 1 week. Those in the high-risk group and those taking nonsteroidal anti-inflammatory drugs (NSAIDs) underwent endoscopy promptly. Alarm symptoms were as follows: weight loss (10 or more pounds over 8 weeks), recurrent vomiting, dysphagia, bleeding, or anemia.

RESULTS

Of 2627 patients enrolled, 1017 were in the low-risk group and 1610 in the high-risk group. Twenty-three patients (0.9%) had gastroesophageal cancers (20 gastric, 3 esophageal). Four patients with cancer (17.4%) were in the low-risk group (3 gastric, 1 esophageal); all except the patient with esophageal cancer had a positive serology test. In the high-risk group, 19 patients had cancer (17 gastric, 2 esophageal).

CONCLUSION

Gastric cancer is relatively frequent among young patients with dyspepsia who have no alarm features in Hong Kong. This finding raises concerns as to the safety of the "test-and-treat" strategy for the management of patients with dyspepsia in Asia.

K562 cells implicate increased chromatin accessibility in Alu transcriptional activation

Alu repeats in K562 cells are unusually hypomethylated and far more actively transcribed than those in other human cell lines and somatic tissues. Also, the level of Alu RNA in K562 cells is relatively insensitive to cell stresses, namely heat shock, adenovirus infection and treatment with cycloheximide, which increase the abundance of Alu RNA in HeLa and 293 cells. Recent advances in understanding the interactions between DNA methylation, transcriptional activation and chromatin conformation reveal reasons for the constitutively high level of Alu expression in K562 cells. Methylation represses transcription of transiently transfected Alu templates in all cell lines tested but cell stresses do not relieve this repression suggesting that they activate Alu transcription through another pathway. A relatively large fraction of the Alus within K562 chromatin is accessible to restriction enzyme cleavage and cell stresses increase the chromatin accessibility of Alus in HeLa and 293 cells. Cell stress evidently activates Alu transcription by rapidly remodeling chromatin to recruit additional templates.

Impaired vascular dynamics in normotensive diabetic rats induced by streptozotocin: tapered T-tube model analysis

This study is to explore the changes of arterial mechanical properties in streptozotocin (STZ)-diabetic rats, based on the exponentially tapered T-tube model. Rats given STZ 65 mg kg(-1)i.v. are compared with untreated weight- and age-matched controls. A high-fidelity pressure sensor and electromagnetic flow probe measured pulsatile pressure and flow waves in the ascending aorta, respectively. Diabetic rats exhibit isobaric vasodilatation that is characterized by an increase in cardiac output and no significant changes in aortic pressure. Total peripheral resistance of diabetic rats is lower than that of weight- and age-matched controls. Diabetic rats have higher total peripheral compliance (2.86+/-0.70 microl mm Hg(-1)) than do weight- (1.77+/-0.34 microl mm Hg(-1)) and age-matched (1.87+/-0.69 microl mm Hg(-1)) controls. Aortic characteristic impedance is reduced from 0.017+/-0.003 mm Hg min kg ml(-1)in weight- and 0.020+/-0.004 mm Hg min kg ml(-1)in age-matched controls to 0.010+/-0.004 mm Hg min kg ml(-1)in diabetic rats. Moreover, diabetic rats show shorter wave transit time in lower body circulation (17.86+/-1.91 ms) than do weight- (20.45+/-1.91) and age-matched (23.05+/-2.04 ms) controls. Under isobaric vasodilatation, the decreased resistance and increased compliance in peripheral circulation suggest that the contractile dysfunction of the smooth muscle cells may occur in resistance arterioles in diabetes. With unaltered aortic pressure, an impairment in aortic distensibility of STZ-diabetic rats is manifest on the reduced wave transit time rather than on the diminished aortic characteristic impedance.

An exposure system to study the effects of water-soluble gases on PM-induced toxicity

An aerosol generation and exposure system to evaluate the role of water-soluble gases in particulate matter (PM)-induced injury was designed, built, and validated by generating test atmospheres to study the role of hydrogen peroxide in PM-induced toxicity. In this system, particle number concentration, size distribution, hydrogen peroxide concentration, and water concentration can all be varied. An ammonium sulfate aerosol with mass median diameter 0.46 +/- 0.01 microm was used as a model atmospheric aerosol because ammonium sulfate is a major component of the fine aerosol, and the water uptake of ammonium sulfate aerosol is well characterized. The following four test atmospheres were generated: (1) ammonium sulfate aerosol, (2) an aerosol containing hydrogen peroxide and ammonium sulfate, (3) vapor-phase hydrogen peroxide, and (4) particle-free air. All test atmospheres were maintained at a relative humidity of 85%. Particle size distribution, number concentration, total hydrogen peroxide concentration, temperature, and relative humidity were measured continuously in the exposure chamber. The gas-particle partitioning of hydrogen peroxide was calculated using total hydrogen peroxide concentration, the Henry's law constant for hydrogen peroxide in water, and aerosol water content. We found that the aerosol generation system produced stable concentrations throughout the 2-hour exposures.

Coherent EEG indicators of cognitive binding during ambiguous figure tasks

We tested the hypothesis that perception of an alternative image in ambiguous figures would be manifest as high-frequency (gamma) components that become synchronized over multiple scalp sites as a "cognitive binding" process occurs. For 171 combinations of data from 19 electrodes, obtained from 17 subjects and 10 replicate stimuli, we calculated the difference in correlation between the response to first seeing an ambiguous figure and when the alternative percept for that figure became consciously realized (cognitively bound). Numerous statistically significant correlation differences occurred in all frequency bands tested with ambiguous-figure stimulation, but not in two kinds of control data (a reaction-time test to sound stimuli and a no-task, mind-wandering test). Statistically significant correlation changes were widespread, involving frontal, parietal, central, and occipital regions of both hemispheres. Correlation changes were evident at each of five frequency bands, ranging up to 62.5 Hz. Most of the statistically significant correlation changes were not between adjacent sites but between sites relatively distant, both ipsilateral and contralateral. Typically, these correlation changes occurred in more than one frequency band. These results suggest that cognitive binding is a distinct mental state that is reliably induced by ambiguous-figure perception tasks. Coherent oscillations at multiple frequencies may reflect the mechanism by which such binding occurs. Moreover, different coherent frequencies may mediate different components of the total cognitive-binding process.

One-week ranitidine bismuth citrate versus colloidal bismuth subcitrate-based anti-Helicobacter triple therapy: a prospective randomized controlled trial

OBJECTIVE

The efficacy of 1 wk bismuth triple therapy is adversely influenced by the presence of metronidazole resistance. In vitro studies suggest that ranitidine bismuth citrate (RBC) plus metronidazole exhibit synergistic activity against metronidazole resistant strains of Helicobacter pylori (H. pylori). Whether this confers a superior clinical efficacy remains unproven. This study compared the efficacy of RBC-based triple therapy with bismuth triple therapy in eradication of H. pylori.

METHODS

Patients with H. pylori-related ulcer disease or gastritis were randomized to receive either 400/mg of RBC twice daily plus 400/mg of metronidazole and 500/mg of tetracycline four times daily for 1 wk (RMT) or 120/mg of colloidal bismuth subcitrate, 400/mg of metronidazole, and 500/mg of tetracycline, all given four times daily for 1 wk (BMT). Metronidazole susceptibility was determined by the E-test and pretreatment resistance was defined as minimum inhibitory concentration > or = 32/mg/L.

RESULTS

Of 100 consecutive patients randomized, two patients were lost to follow-up in each group. Forty-three of 85 (51%) H. pylori isolates were metronidazole resistant. Per-protocol cure rate for RMT and BMT was 40 of 41 (98%) and 37 of 44 (84%), respectively (p = 0.058). Intent-to-treat cure rate for RMT and BMT was 46 of 50 and 41 of 50, respectively (92% vs 82%, p = 0.23). A significantly higher eradication of metronidazole resistant H. pylori was observed in the RMT group (25 of 25, 100%) than in the BMT group (12 of 16, 75%), (p = 0.018). Side effects observed in the two treatment groups were comparable.

CONCLUSIONS

One week of RBC triple therapy with metronidazole and tetracycline is an effective anti-Helicobacter therapy. This regimen is more appropriate in areas of high prevalence of metronidazole resistance.

Anti-Helicobacter pylori treatment in bleeding ulcers: randomized controlled trial comparing 2-day versus 7-day bismuth quadruple therapy

BACKGROUND

One-week bismuth triple therapy has been established to be highly effective in curing H. pylori infection, but patient compliance has been the major factor of success in therapy. For patients hospitalized for ulcer bleeding, an effective regimen that can completed before discharge will ensure full compliance.

AIM

To compare 2-day versus 1-wk bismuth triple therapy plus omeprazole in curing H. pylori infection and bleeding peptic ulcers.

METHODS

100 patients with non-actively bleeding duodenal (DU) or gastric ulcers (GU) and confirmed H. pylori infection were randomized to receive either bismuth subcitrate 120 mg, tetracycline 500 mg, and metronidazole 400 mg four times daily for 1 wk (OBTM-7) or bismuth subcitrate 240 mg, tetracycline 500 mg, and metronidazole 400 mg four times daily for 2 days (OBTM-2). Both groups of patients also received omeprazole 20 mg twice daily for the first week. In the OBTM-2 group, the anti-Helicobacter therapy was finished during hospitalization. Endoscopy was repeated 5 wk after randomization to monitor ulcer healing and determine H. pylori status. Side effects related to the anti-Helicobacter therapy was graded as follows: A, mild discomfort, which did not affect daily activity; B, moderate discomfort affecting daily activity; and C, severe discomfort and patients discontinued therapy.

RESULTS

Forty-six patients in the OBTM-2 group and 50 in the OBTM-7 group returned for follow-up endoscopy. With an intention-to-treat analysis, ulcer healing was achieved in 44 of 46 patients (95.7%) in the OBTM-2 group versus 49 of 50 (98%) in the OBTM-7 group, p = 0.61. H. pylori eradication was successful in 35 of 46 patients (76.1%) in the OBTM-2 and in all 50 patients (100%) in the OBTM-7 group, p = 0.00024. There was no difference in the severity of side effects experienced by the patients in the OBTM-2 group than in the OBTM-7 group (19 vs 32%, p = 0.16). None of the patients had rebled during the period of follow-up.

CONCLUSION

Despite similar efficacy in ulcer healing, the 2-day quadruple therapy is less effective than the 1-wk regimen in curing H. pylori infection.

Interleukin-1-beta changes the expression of metalloproteinases in the vitreous humor and induces membrane formation in eyes containing preexisting retinal holes

PURPOSE

Proliferative vitreoretinopathy occurs when cells migrate into the vitreous humor, where they proliferate and produce a membrane composed of extracellular matrix. Interleukin-1-beta (IL-1-beta) may be involved in these processes because it is chemotactic and mitogenic, and it stimulates metalloproteinase production. In the present study, the effects of intravitreally injected IL-1-beta on retinal membrane formation and the associated changes in metalloproteinase content of vitreous humor were examined.

METHODS

Rabbit eyes were injected with IL-1-beta in a buffer, with or without the prior creation of retinal holes. Control eyes received the buffer alone or no injection, with or without retinal holes. Animals were examined by slit lamp biomicroscopy and indirect ophthalmoscopy for 1 month. Zymography was performed on a portion of vitreous humor to assess collagenase content, and the remaining tissue was subjected to histologic analysis.

RESULTS

Intraocular IL-1-beta induced perilimbal vessel engorgement, keratic precipitates, synechiae, flare, lens deposits, optic disk hyperemia, and granulomatous formations that gradually subsided during the first week. Intravitreal injection of IL-1-beta in eyes with preexisting retinal holes additionally induced membrane formation. Zymographic analysis of vitreous humor from animals sacrificed 24 hours after IL-1-beta injection showed a 100-kd and a 65-kd gelatinase, whereas control vitreous humor contained predominantly a single gelatinase species of approximately 65 kd. Retinal holes did not affect IL-1-beta induction of the 100-kd gelatinase.

CONCLUSIONS

IL-1-beta induces a 100-kd gelatinase in the vitreous humor and epiretinal membrane formation in eyes containing preexisting retinal holes. The presence of retinal holes and abnormal production of cytokines may lead to a cascade of events, including aberrant extracellular matrix remodeling, that result in proliferative diseases of the eye.

Phenotypic expression of the Pseudomonas syringae pv. syringae 61 hrp/hrm gene cluster in Escherichia coli MC4100 requires a functional porin

Plants, in general, appear to be able to detect the presence of incompatible Pseudomonas syringae strains by a hypothetical cell-cell recognition process to initiate inducible defense mechanisms that contribute to disease resistance. A 25-kb hrp/hrm gene cluster isolated from P. syringae pv. syringae 61(pHIR11) enables Escherichia coli to elicit a hypersensitive response (HR), a plant response generally considered to be a manifestation of recognition and resistance. To identify the nature of the HR-eliciting signal produced by E. coli cells carrying pHIR11, bacterial surface features were surveyed by immunological and biochemical procedures. No immunoreactive epitopes or outer membrane proteins were detected that were associated with expression of the P. syringae pv. syringae 61 hrp/hrm cluster in E. coli MC4100. Phenotypic expression of the P. syringae pv. syringae 61 hrp/hrm cluster in E. coli MC4100, however, was found to be dependent upon ompC and ompF, which control outer membrane permeability to hydrophilic solutes. The results suggest that deployment of the HR-eliciting signal occurs via outer membrane porins and imply that a low-molecular-weight, hydrophilic factor mediates signal exchange between the bacterium and the responding plant cell.

The inhibitory effect of deferoxamine on DNA synthesis in human lymphocytes

As an iron-chelating agent, deferoxamine (DFO) is widely used in treating iron poisoning and disorders of iron overload. This study demonstrates that DFO is a potent S-phase inhibitor of DNA synthesis in human lymphocytes in vitro, and this inhibitory effect of DFO is reversible by adding appropriate amounts of ferric ion. As a nontoxic and selective-S-phase inhibitor, it may play a role in immunosuppression in experimental and therapeutic situations. It may even become an auxiliary therapy for leukemia or other malignant tumors.

A rapid and precise system for lead determination in whole blood

The paper describes a heated furnace atomic absorption method for determining lead in whole blood using an automated sample introduction system. It is direct and rapid. No sample pretreatment is required and up to 30 samples per hour can be analyzed. Precision and accuracy data are presented. The system has been applied to both macro (venipuncture) and micro (capillary) samples. The method uses physiologically-bound lead standards to compensate for matrix effects. It has been used in the screening of target populations and for confirming elevated blood lead levels in the California Department of Health Services Childhood Lead Program.