Reversing multidrug resistance by RNA interference through the suppression of MDR1 gene in human hepatoma cells.

Aim: To reverse the multidrug resistance (MDR) by RNA interference (RNAi)-mediated MDR1 suppression in hepatoma cells.

Methods: For reversing MDR by RNAi technology, two different short hairpin RNAs (shRNAs) were designed and constructed into pGenSil-1 plasmid, respectively. They were then transfected into a highly adriamycin-resistant HepG2 hepatoma cell line (HepG2/ADM).

[Effectiveness of combined surgery for treating severe obstructive sleep apnea hypopnea syndrome].

Objective: To explore the efficiency of a comprehensive surgical approach of genioglossus advancement and hyoid suspension (GAHM) plus uvulopalatopharyngoplasty (UPPP) for treating severe obstructive sleep apnea hypopnea syndrome (OSAHS) and to evaluate related factors on surgery outcomes.

Methods: Eighteen patients with severe OSAHS (apnea hypopnea index, AHI > 40/h) confirmed with polysomnography received genioglossus advancement and hyoid suspension plus uvulopalatopharyngoplasty. The obstruction in both the oropharynx and the hypopharynx were evaluated by preoperative physical examination, fiberoptic pharyngolaryngoscopy, cephalometry, and computed tomography of the upper airway.

[Anatomic and spiral computed tomographic study of the genial tubercles for genioglossus advancement].

Objective: To study anatomic and computed tomographic measurements of Chinese mandibular genial tubercles and to evaluate the correlations between them.

Methods: The axial images were taken by spiral CT in 40 adult human skulls with 1 mm thick section from infraorbital margin to menton. Sagittal plane reconstruction was produced through mandibular central line.

Antimalarial activities of new pyrrolo[3,2-f]quinazoline-1,3-diamine derivatives.

WR227825 is an antimalarial pyrroloquinazolinediamine derivative with a high potency but a low therapeutic index. A series of carbamate, carboxamide, succinimide, and alkylamine derivatives of WR227825 were prepared to search for compounds with an improved therapeutic index. The new acetamides and imide showed potent cell growth inhibition against four clones of Plasmodium falciparum (D-6, RCS, W-2, and TM91C235), with a 50% inhibitory concentration of approximately 0.

[Genioglossus advancement and hyoid suspension plus uvulopalatopharyngoplasty for severe OSAHS].

Objective: To explore a comprehensive surgical approach of genioglossus advancement and hyoid suspension plus uvulopalatopharyngoplasty on the treatment of severe obstructive sleep apnea hypopnea syndrome.

Method: Eighteen patients with severe OSAHS (RDI > 40)diagnosed by polysomnography. The obstruction in both the oropharynx and the hypopharynx were determined by preoperative physical examination, fiberoptic pharyngolaryngoscopy, cephalometry, and computed tomography of the upper airway.

Synergistic effect of bromocriptine and tumor necrosis factor-alpha on reversing hepatocellular carcinoma multidrug resistance in nude mouse MDR1 model of liver neoplasm.

Aim: To investigate the effect of bromocriptine (BCT) and tumor necrosis factor-alpha (TNF-alpha) on hepatocellular carcinoma (HCC) multidrug resistance (MDR) in nude mouse MDR model of liver neoplasm.

Methods: Human hepatocarcinoma cell line HepG(2), drug resistant hepatocarcinoma cell line HepG(2)/adriamycin (ADM) and hepatocarcinoma cell line transfected with TNF-alpha gene HepG(2)/ADM/TNF were injected into the liver of nude mice via orthotopic implantation and MDR model of liver neoplasm in vivo was established (HepG(2), ADM, TNF, BCT groups). Among these groups, BCT group and TNF group were treated with BCT through gastric canal.

Unambiguous synthesis and prophylactic antimalarial activities of imidazolidinedione derivatives.

WR182393, a guanidinoimidazolidinedione derivatives with potent causal prophylactic antimalarial activity by intramuscular injection, was previously prepared by treatment of chloroproguanil and diethyl oxalate, yielding a mixture of two closely related isomers. Poor solubility of the mixture made the separation and purification impossible. To overcome the separation problem, new and facile unambiguous syntheses of the two active components were reported.

DNAzyme-mediated cleavage of survivin mRNA and inhibition of the growth of PANC-1 cells.

Background And Aim: Survivin has functions in both the regulation of cell division and the inhibition of apoptosis, and it is expressed in most human tumors but not in normal adult tissues. It is a potential target for cancer gene therapy. In the present study, we designed a DNAzyme targeting human survivin mRNA and tried to determine its effect on human pancreatic carcinoma cell line PANC-1.

[Anatomic characteristics and relationship of lingual artery and hypoglossal nerve with tongue base].

Objective: To investigate the anatomic characteristics of lingual artery and hypoglossal nerve and relationship between lingual artery and hypoglossal nerve in tongue base, for the purpose of improving data with clinic and increasing safety in the operation of tongue base.

Method: Twenty extraoral dissections of the submandibular region were performed on 10 human cadavers. The origin and distribution of lingual artery and hypoglossal nerve were observed: (1) The lingual artery was divided into four segments, length and adjacent organs were observed and measured; (2) The hypoglossal nerve length and adjacent organs were observed and measured; (3) The anatomic relationship of lingual artery and hypoglossal nerve was observed and measured.

[Hypoxia-inducible factor-1 alpha dependent expression and significance of the related multidrug resistance genes induced by hypoxia in human hepatocarcinoma cell].

Objective: To explore the mechanism of multidrug resistance of hepatocellular carcinoma induced by hypoxia and the potential role of hypoxia-inducible factor-1 alpha (HIF-1 alpha) and multidrug resistance related genes.

Methods: Human hepatocarcinoma cell lines HepG2 cells were exposed to hypoxia and were transfected by plasmid HIF-1 alpha/PCDNA3, respectively. The expressions of multidrug resistance gene (mdr1), multidrug resistance protein (MRP1), and lung resistance protein (LRP) gene at the mRNA and the protein levels in the above two groups were respectively analyzed by real-time fluorescent quantitative PCR and Western-blot technique.

[Expression of survivin gene in pancreatic carcinoma].

Objective: To determine the expression status of survivin gene in pancreatic carcinoma.

Methods: Expression of survivin gene was evaluated by immunohistochemistry, Western Blot and RT-PCR in 59 cases of pancreatic carcinoma along with their corresponding adjacent benign tissues, 11 cases of chronic pancreatitis, and 7 pancreatic carcinoma cell lines.

Results: The positive expression rate of survivin in pancreatic carcinoma was 72.

[Applied anatomic study for genioglossus advancement].

Objective: To provide anatomic basis for genioglossus advancement.

Method: Forty adult cadaver heads (male=29, female=11) were dissected to measure genial tubercles and observe the start-stop points of genioglossus muscle and geniohyoid muscle.

Result: The genioglossus muscle originates from the superior mental spine, and the geniohyoid muscle originates from the inferior mental spine.

[Preventive effects of montelukast on the collagen expression of pulmonary arterioles in rats with chronic hypoxia].

Objective: To evaluate the preventive effects of montelukast on the collagen expression of pulmonary arterioles in chronic hypoxic rats.

Methods: Thirty male Wistar rats were randomly divided into three groups: control group, hypoxic group and montelukast preventive group. The animal model of pulmonary hypertension was established by exposing the rats to normabaric hypoxic conditions 8 hours q.

Antisense bcl-2 transfection up-regulates anti-apoptotic and anti-oxidant thioredoxin in neuroblastoma cells.

Antisense bcl-2 therapy combined with chemotherapy has been proved to be effective in various tumors. However, the role played by antisense bcl-2 therapy alone is not clear. In this study, we compared the apoptosis and the protein profiles of antisense bcl-2 transfected human neuroblastoma SK-N-MC cells to the control cells.

Structure identification and prophylactic antimalarial efficacy of 2-guanidinoimidazolidinedione derivatives.

The reported synthetic procedure of WR182393, a 2-guanidinoimidazolidinedione derivative with high prophylactic antimalarial activity, was found to be a mixture of three closely related products. Poor solubility of WR182393 in both water and organic solvents and its impractical synthetic method have made the purification and structure identification of the reaction mixture a highly challenging task. The problems were circumvented by prodrug approach involving carbamate formation of the mixture, which enhances the solubility of the mixture in common organic solvents and facilitates the separation and structure determination of the two products.

[The effects of losartan on pulmonary arterial collagen and AT1 in chronic hypoxic rats].

Objective: To investigate the effects of losartan on pulmonary arterial collagen and AT1 in chronic hypoxic rats.

Methods: Thirty male SD rats were randomly divided into three groups: control group, hypoxic group and therapeutic group. The animal model of pulmonary hypertension was established by exposing the rats to normabaric hypoxic conditions for three weeks.

Involvement of extracellular signal-regulated kinase/mitogen-activated protein kinase pathway in multidrug resistance induced by HBx in hepatoma cell line.

Aim: To investigate the molecular mechanism of the influence of HBx protein on multidrug resistance associated genes: multidrug resistance 1 (MDR-1), multidrug related protein (MRP-1), lung resistance related protein (LRP) in hepatoma cells and the potential role of extracellular signal-regulated kinase/mitogen-activated protein kinase (ERK/MAPK) pathway in this process.

Methods: A cell model stably expressing the HBx protein was established by liposome-mediated transfection of HBx gene into HepG2 cell line. The expression of multidrug resistance associated genes and proteins was detected by RT-PCR and Western blot.

[Expression of MCP-1 in airway of rats with COPD].

Objective: To explore the role of monocyte chemoattractant protein-1 (MCP-1) in the pathogenesis of chronic obstructive plumonary disease (COPD).

Methods: Rat COPD model was established by exposing the rats to cigarette smoke daily. After COPD model was set up, bronchoalveolar lavage was performed.

Window of opportunity of cerebral hypothermia for postischemic white matter injury in the near-term fetal sheep.

Postresuscitation cerebral hypothermia is consistently neuroprotective in experimental preparations; however, its effects on white matter injury are poorly understood. Using a model of reversible cerebral ischemia in unanesthetized near-term fetal sheep, we examined the effects of cerebral hypothermia (fetal extradural temperature reduced from 39.4 +/- 0.

[Distinction between benign and malignant pheochromocytomas].

Objectives: To investigate the differences in morphology, immunohistochemistry, DNA ploidy status, LOH and MSI of 11q13 and 1p between benign and malignant pheochromocytomas, and to find the marker or markers useful in distinction between benign and malignant pheochromocytoma or for predicting the malignant potential of this tumor.

Methods: Twenty-two cases of clinically documented benign and malignant pheochromocytomas from the files of Peking Union Medical College Hospital were analyzed. Aside from histological study, Ki-67, p53, CgA, S-100, PCNA and survivin immunohistochemistry studies were performed.

Anti-AIDS agents. Part 61: Anti-HIV activity of new podophyllotoxin derivatives.

A series of novel podophyllotoxin derivatives containing structural modifications at C-4 (7-14), C-4' (16-17), and the methylenedioxy A-ring (23-28) was synthesized and tested for inhibition of HIV replication. Four of these compounds (25-28) were previously reported to show EC(50) values of <0.001 microg/mL and therapeutic index (TI) values >120.

Fetal heart rate variability and brain stem injury after asphyxia in preterm fetal sheep.

This study was undertaken to determine the mechanisms mediating changes in fetal heart rate variability (FHRV) during and after exposure to asphyxia in the premature fetus. Preterm fetal sheep at 0.6 of gestation (91 +/- 1 days, term is 147 days) were exposed to either sham occlusion (n = 10) or to complete umbilical cord occlusion for either 20 (n = 7) or 30 min (n = 10).

TGF beta-1 and neurological function after hypoxia-ischemia in adult rats.

The present study compared the short-term and long-term neuroprotective and neurobehavioral effects of transforming growth factor beta-1 (TGF beta-1) after hypoxic-ischemic injury in adult rats. TGF beta-1 (10 ng) or vehicle were administered intracerebroventricularly (i.c.

[Preventive effects of urapidil on hypoxic pulmonary hypertension in rats].

Objective: To investigate the preventive effect of urapidil, an alpha 1-adrenoceptor antagonist, on hypoxic pulmonary vascular remodeling.

Methods: Twenty-one male Sprague-Drawley rats were randomly allocated into three groups: control group, hypoxic group and hypoxic plus urapidil group. The animal model of hypoxic pulmonary hypertension was established by exposing the rats to normobaric hypoxic condition for three weeks, and the rats of hypoxic plus urapidil group were treated with urapidil 10 mg/kg before and after hypoxic processing.

[Clinical and pathological features of congenital bronchial cyst].

Objective: To study the clinical and pathological features of congenital bronchial cysts.

Methods: The clinical, X-ray, CT and histopathologic manifestations were retrospectively reviewed in 30 patients with congenital bronchial cysts.

Results: There were 23 patients with intrapulmonary bronchogenic cysts, 5 patients with mediastinal bronchogenic cysts, and 2 patients with ectopic bronchogenic cysts.