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Huan Wang

Publications and source records attributed to Huan Wang.

At least 37 records · Page 2Linked to original sources
PubMed2005

Polycyclic aromatic hydrocarbon-induced CYP1B1 activity is suppressed by perillyl alcohol in MCF-7 cells.

Perillyl alcohol (POH) is a dietary monoterpene with potential applications in chemoprevention and chemotherapy. Although clinical trials are under way, POH's physiological and pharmacological properties are still unclear. In the present study, the effect of POH on polycyclic aromatic hydrocarbon (PAH)-induced genotoxicity, and the related expression were examined in MCF-7 cells. Exposure to environmental toxicant increases the risk of cancer. Many of these compounds are pro-carcinogens and are biotransformed into their ultimate genotoxic structures by xenobiotic metabolizing enzymes. CYP1A1 and 1B1 are enzymes that catalyze the biotransformation of dimethylbenz[a]anthracene (DMBA). Our data revealed that 0.5 microM of POH was effective in blocking DMBA-DNA binding. Ethoxyresorufin-O-deethylase (EROD) assay indicated that the administration of POH inhibited the DMBA-induced enzyme activity in MCF-7 cells. Enzyme kinetic analysis revealed that POH inhibited CYP1B1 but not CYP1A1 activity. Quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) assay also demonstrated that the monoterpene reduced CYP1B1 mRNA abundance induced by DMBA. The present study illustrated that POH might inhibit and downregulate CYP1B1, which could protect against PAH-induced carcinogenesis.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed2005

Phospholipase C epsilon modulates beta-adrenergic receptor-dependent cardiac contraction and inhibits cardiac hypertrophy.

Phospholipase C (PLC) epsilon is a recently identified enzyme regulated by a wide range of molecules including Ras family small GTPases, Rho A, Galpha(12/13), and Gbetagamma with primary sites of expression in the heart and lung. In a screen for human signal transduction genes altered during heart failure, we found that PLCepsilon mRNA is upregulated. Two murine models of cardiac hypertrophy confirmed upregulation of PLCepsilon protein expression or PLCepsilon RNA. To identify a role for PLCepsilon in cardiac function and pathology, a PLCepsilon-deficient mouse strain was created. Echocardiography indicated PLCepsilon(-/-) mice had decreased cardiac function, and direct measurements of left ventricular contraction demonstrated that PLCepsilon(-/-) mice had a decreased contractile response to acute isoproterenol administration. Cardiac myocytes isolated from PLCepsilon(-/-) mice had decreased beta-adrenergic receptor (betaAR)-dependent increases in Ca2+ transient amplitudes, likely accounting for the contractile deficiency in vivo. This defect appears to be independent from the ability of the betaAR system to produce cAMP and regulation of sarcoplasmic reticulum Ca2+ pool size. To address the significance of these functional deficits to cardiac pathology, PLCepsilon(-/-) mice were subjected to a chronic isoproterenol model of hypertrophic stress. PLCepsilon(-/-) mice were more susceptible than wild-type littermates to development of hypertrophy than wild-type littermates. Together, these data suggest a novel PLC-dependent component of betaAR signaling in cardiac myocytes responsible for maintenance of maximal contractile reserve and loss of PLCepsilon signaling sensitizes the heart to development of hypertrophy in response to chronic cardiac stress.

Animals↗
PubMed2005

[Application of adjustable oblique position for microendoscopic discectomy].

OBJECTIVE: To compare the adjustable oblique position with prone position in microendoscopic discectomy (MED) and to evaluate its advantages. METHODS: One hundred and twenty-eight patients who underwent MED during August 2000 and August 2002 were studied. Forty-seven cases were positioned prone, 81 cases were positioned with adjustable oblique position. Operating time, blood loss and patient endurance were recorded and compared. The airway resistance of 29 lumbar disorder patients was measured when they were positioned supine, lateral and prone respectively after general anesthesia. RESULTS: There was statistically significant difference between 2 groups in operating time, blood loss and endurance. In prone position group, when operating time lasted for more than 50 min, 75% patients felt hurt on the skin of rib arch, and 38% patients presented dizzy and nausea. And all the patients had erythema on the rib arch. In the adjustable oblique position group, 3 cases had shoulder pain after operation, and 1 case had 4 days' common poroneal nerve paralysis. The airway resistance of patients with prone position was significantly higher than those with supine and lateral positioned patients. (P < 0.05). CONCLUSION: The adjustable oblique position in MED had the following advantages: (1) Do not limit the movement of chest and help reduce intra-abdominal pressure and epidural bleeding; (2) Give the lumbar spine the largest degree of flexion and the largest interlaminar space, which prevents injury of facet joint; (3) Increase posterior intervertebral space and make disectomy easier and exposure of nerve root and nerve root canal clearer; (4) The patients feel comfortable and can adjust the position of lumbar spine and lower extremity; (5) The monitor has the same direction with doctor, and it is easy for the doctor to operate; (6) Doctor can sit during operation.

Adolescent↗
PubMed2005

The terminal phase of cytokinesis in the Caenorhabditis elegans early embryo requires protein glycosylation.

RNA interference (RNAi) was used to characterize the requirement of protein glycosylation for cell membrane stability during cytokinesis in the early embryo. This screen targeted 13 enzymes or components of polypeptide sugar transferases that initiate either N-glycosylation or three different pathways of O-glycosylation. RNAi of genes in the mucin-type and epidermal growth factor-fringe glycosylation pathways did not affect cytokinesis. However, embryos deficient in N-glycosylation exhibited a variable inability to complete cytokinesis. The most potent block in early embryonic cell division was obtained by RNAi of the polypeptide xylose transferase (ppXyl-T), which is required to initiate the proteoglycan modification pathway. Two generations of ppXyl-T RNAi-feeding treatment reduced the body size, mobility, brood size, and life span of adult animals. Embryos escaping ppXyl-T and Gal-T2 RNAi lethality develop to adulthood but have cytokinesis-deficient offspring, suggesting that glycosyltransferases in the proteoglycan pathway are maternal proteins in the early embryo. Gal-T2::GFP fusions and anti-Gal-T2 antibodies revealed a perinuclear staining pattern, consistent with the localization of the Golgi apparatus. RNAi in green fluorescent protein (GFP)-tagged strains to follow tubulin, PIE-1, and chromatin showed that deficient proteoglycan biosynthesis uncouples the stability of newly formed cell membranes from cytokinesis, whereas cleavage furrow initiation, mitotic spindle function, karyokinesis, and partitioning of intrinsic components are intact.

Amino Acid Sequence↗
PubMed2005

Hydroxychalcones exhibit differential effects on XRE transactivation.

Chalcones are phenolic compounds that can be isolated from plants. Previous studies have described some pharmacological applications for these compounds. Making use of our established reporter gene system, we determined the effect of five hydroxychalcones--2-hydroxychalcone, 2'-hydroxychalcone, 4-hydroxychalcone, 4,2',4'-trihydroxychalcone, and 3,4,2',4'-tetrahydroxychalcone--on the cellular xenobiotic responsive element (XRE)-transactivation. The interference of chalcones acting against polycyclic aromatic hydrocarbon (PAH)-DNA binding was also examined. Enzyme inhibition assays of cytochrome P450 (CYP) 1A1 and CYP1B1 were initially performed on recombinant protein expressed in insect microsomes. 2'-Hydroxychalcone and 2-hydroxychalcone were the most effective among the tested hydroxychalcones. The two hydroxychalcones had comparable IC50 values for CYP1A1 and CYP1B1, which were determined to be at the micromolar and submicromolar range, respectively. However, reporter gene assays indicated that 2'-hydroxychalcone suppressed XRE-transactivation, whereas 2-hydroxychalcone induced it when 7,12-dimethylbenz[a]anthracene (DMBA) was co-administered. In the absence of DMBA, 10 microM 2-hydroxychalcone and 2'-hydroxychalcone increased XRE-transactivation by 18- and 2.5-fold, respectively, while other chalcones did not significantly alter the response. Cultures treated with the two hydroxychalcones also displayed separate trends in ethoxyresorufin-O-deethylase (EROD) activity and DMBA-DNA covalent binding. In summary, the present study illustrated that the inhibition of hydroxychalcone on CYP1 enzymes and XRE-transactivation was affected by the position and number of hydroxyl groups in its structure.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed2005

Transaxillary carotid stenting: technical case report.

OBJECTIVE AND IMPORTANCE: As endovascular neurointerventions continue to evolve rapidly, angioplasty and stenting of both the extracranial and intracranial vessels have become more routine procedures. When the transfemoral approach is contraindicated or technically difficult, familiarity with alternative access techniques becomes essential. We report a successful transaxillary carotid stenting in a patient with an axillary bifemoral bypass graft. CLINICAL PRESENTATION: A 77-year-old man presented with a symptomatic high-grade stenosis (80%) of the left internal carotid artery. Because of the increased risk of general anesthesia related to his advanced age and severe comorbidities, stenting of the left internal carotid artery was considered. A left transaxillary approach was chosen because of the presence of an axillary bifemoral bypass graft. TECHNIQUE: Under ultrasound guidance, the left axillary artery was successfully punctured and cannulated. After a 0.038 Magic Torque wire (Boston Scientific/Medi-Tech, Watertown, MA) was anchored with the tip of the wire in the distal left occipital artery, a 7-French (outer diameter) Vista Bright guiding sheath (Cordis, Miami, FL) was successfully positioned in the mid left common carotid artery, with an MPA catheter (Cordis) used as guiding support. Subsequently, two Precise stents (Cordis) were successfully deployed across the stenosis, yielding a satisfactory angiographic result. CONCLUSION: With proper patient selection and the use of ultrasound guidance during the initial puncture, the transaxillary approach is a safe and technically feasible alternative to the transfemoral approach when performing carotid stenting.

Aged↗
PubMed2005

Successful intra-arterial basilar artery thrombolysis in a patient with bilateral vertebral artery occlusion: technical case report.

OBJECTIVE AND IMPORTANCE: Basilar artery occlusion is a clinical event with an exceedingly high mortality rate. Improved survival is closely associated with successful recanalization of the occluded basilar artery. Bilateral vertebral artery occlusion (BVAO) is a unique disease entity that effectively denies any direct access to the basilar artery for endovascular rescue therapy. We report a case of successful intra-arterial basilar artery thrombolysis in a patient with BVAO. CLINICAL PRESENTATION: A 78-year-old man was transferred to our hospital after intravenous administration of tissue plasminogen activator and with deteriorating neurological status requiring intubation. His clinical presentation was highly suggestive of acute basilar artery thrombosis. The cerebral angiogram showed a BVAO and collateral flow reconstituting both distal extracranial vertebral arteries but with significant contrast stasis. There was no retrograde filling of the basilar artery through the only angiographically visible posterior communicating artery. TECHNIQUE: Selective catheterizations of the left occipital artery and the left ascending cervical branch of the thyrocervical trunk were performed to deliver a total of 12 mg of tissue plasminogen activator. At that point, the patient showed significant neurological improvement. The post-tissue plasminogen activator angiogram showed improved flow through the basilar artery. The patient was independent and well at his 1-year follow-up visit. CONCLUSION: Knowledge of potential collateral pathways is important when direct access to the main intracranial vessels is not available. Basilar artery thrombolysis through collateral vessels is clinically effective when a direct approach to the artery is not feasible.

Aged↗
PubMed2005

Endovascular treatment of intracranial aneurysms in the elderly: single-center experience in 63 consecutive patients.

OBJECTIVE: With a globally aging population, it is imperative to develop specific treatment strategies for intracranial aneurysms in the elderly. However, the optimal management of intracranial aneurysms in the elderly remains controversial, particularly for the unruptured aneurysms. Although endovascular treatment is increasingly being used for the management of aneurysms, large endovascular series in the elderly population are relatively lacking, especially with regard to the unruptured aneurysms. We present our single-center endovascular experience in treating intracranial aneurysms in 63 consecutive patients 70 years of age and older. METHODS: Between November 1998 and December 2003, among a total of 990 patients with intracranial aneurysms treated endovascularly at our center, 63 patients (6%) were 70 years of age or older. Forty-one patients presented with subarachnoid hemorrhage (SAH), and 22 presented with symptomatic unruptured aneurysms. A total of 84 aneurysms were detected in these 63 patients. Only those responsible for either the subarachnoid hemorrhage or clinical symptoms (68 aneurysms) were treated. The aneurysm characteristics, endovascular procedures and techniques, angiographic and clinical outcomes, and complications were reviewed. RESULTS: Selective embolization failed in three aneurysms (4%). In the remaining 65 aneurysms, complete occlusion was achieved in 33 aneurysms (51%), neck remnant was observed in 17 aneurysms (27%), and residual aneurysmal filling was observed in six aneurysms (9%). Parent vessel occlusion was used in the treatment of nine aneurysms (13%). Thirteen procedure-related complications occurred (19%), six of which resulted in clinical complications (9%). Nine deaths (14%) occurred; three (5%) were directly related to the endovascular procedures, and six (9%) were related to the medical complications of SAH. The remaining 54 patients had a mean clinical follow-up time of 13 months (range, 1-47 mo). Ninety-one percent (20 out of 22) of the patients with unruptured aneurysms and 89% (25/28) of the patients with low-grade (Hunt and Hess Grade I and II) ruptured aneurysms achieved excellent outcomes (modified Rankin Scale score, 0-1), whereas 77% (10 out of 13) of the patients with high-grade (Hunt and Hess Grade > or = III) ruptured aneurysms either died or had very poor outcomes (modified Rankin Scale score, 4-5). Angiographic follow-up (mean, 11 mo; range, 3-38 mo) was obtained in 34 of the 54 living patients (63%). Two aneurysms demonstrated minor changes that required no further treatment (5%). Five aneurysms showed major recurrences (17%), all of which were successfully retreated endovascularly. CONCLUSION: The elderly patients should merit strong consideration for endovascular treatment of both ruptured and symptomatic unruptured intracranial aneurysms. However, in elderly patients with high-grade subarachnoid hemorrhage, morbidity and mortality rates remain high.

Aged↗
PubMed2005

Emergent endovascular treatment with direct carotid puncture for exsanguinating Carotid Blowout Syndrome.

INTRODUCTION: Carotid Blowout Syndrome (CBS) carries an exceedingly high mortality rate. Various established endovascular techniques are successful in treating less acute CBS, but exsanguinating patients with hemodynamic compromise continue to pose a significant clinical challenge. METHODS: We report a 53-year-old male with squamous cell carcinoma of the anterior tongue presented with a sentinel hemoptysis followed by a massive oral hemorrhage. The patient suffered a cardiac arrest secondary to acute blood loss, from which he was successfully resuscitated. RESULTS: An occlusion technique is presented involving direct carotid puncture for successful treatment of hemodynamically unstable, exsanguinating patients. CONCLUSION: This technique accomplishes rapid arrest of exsanguination, minimal hemorrhage site manipulation, and successful carotid occlusion.

Balloon Occlusion↗
PubMed2005

Tumefaction of the dural sinuses associated with a coagulopathy following treatment of hydrocephalus in a perinate: case report.

The authors describe an infant with abnormal development of the cerebral venous system associated with in utero ventriculomegaly and perinatal hemorrhage. When the patient was 6 weeks of age progressive ventriculomegaly followed by cerebrospinal fluid diversion resulted in tumefaction of the dural sinuses, intravascular thrombosis, and a coagulopathy. Oral anticoagulation therapy safely reversed the coagulopathy. Serial neuroimaging findings in this unique cascade of pathophysiological events indicated that, despite decreased intracranial pressure after shunt placement, local hemodynamic factors increased the venous resistance to flow and prolonged the transit time. Long-term anticoagulation therapy was associated with improvements in flow, transit time, and tumefaction.

Anticoagulants↗
PubMed2005

[Laparoscopic surgery for benign adrenal tumor: a report of 10 cases].

BACKGROUND & OBJECTIVE: Adrenalectomy is a standard treatment for benign adrenal tumors. Conventional open operation usually results in bigger incisions, more blood loss, and long hospital stay to patients; while laparoscopic approaches could make up above shortcomings, which is used to resect benign adrenal tumors gradually. This article was to report our experiences in laparoscopic adrenalectomy. METHODS: Clinical data of 10 patients with benign adrenal tumors undergone laparoscopic adrenalectomy were retrospectively analyzed to summarize the experiences and techniques in laparoscopic surgery. RESULTS: Of the 10 patients, 9 had tumors successfully resected by laparoscopic adrenalectomy with no severe postoperative complication; 1 switched to receive open surgery during operation, and had mild postoperative corticoadrenal insufficiency. CONCLUSION: Laparoscopic surgery for treatment of benign adrenal tumors has the advantages of minimal invasion, safety, and efficiency, and may be a primary therapeutic option for benign adrenal tumors.

Adenoma↗
PubMed2005

[Treatment of adult prostate sarcoma: a report of six cases with literature review].

BACKGROUND & OBJECTIVE: Primary adult prostate sarcoma is rare. Most patients come to hospital with huge pelvic tumors. Treatment for this disease remains controversial. We reported our experience of treating 6 cases of adult prostate sarcoma, and explore reasonable therapy strategy with literature review. METHODS: Six adult patients with prostate sarcoma were treated in our hospital, 5 underwent cystoprostatectomy combined with urinary diversion, 1 underwent total pelvic exenteration combined with urinary diversion and colostomy; 3 had preoperative intervention to embolize bilateral internal iliac artery, 4 received postoperative radiotherapy. The recent 11 reports published in China with a total of 62 cases were reviewed, 32 of them had radical surgery. The pertinent literatures from other countries were also reviewed. RESULTS: Of our 6 patients, 1 survived with no evidence of disease for 33 months; 1 survived with recurrent tumor for 18 months; 4 died of recurrent sarcoma 5-40 months after surgery. In the whole group of 62 patients, 1-, and 2-year survival rates were 59%, and 34%. CONCLUSION: Up to now, radical surgery is the most effective treatment for adult prostate sarcoma.

Adult↗
PubMed2005

[Study on preparation technology of limonene dropping pills].

OBJECTIVE: To study the technical preparation of limonene dropping pills. METHODS: Orthogonal test was applied to optimize the preparation of limonene dropping pills. RESULTS: The optimized project was as follow: the matrix contained PEG4000: PEG6000 (1:1.5); the refrigerant was liquid paraffin; the rate of limonene to matrix was 1:6 and the temperature of limonene was 70 degrees C; the internal and external diameter of burette was 2.0 mm and 2.4 mm, respectively; the burette was 4cm above the surface of refrigerant; drug was dropped into refrigerant of 15 degrees C at 45 drops per minute. CONCLUSION: The results provide the data for the ascertainment of shaping operation of limonene dropping pills at the manufacturing scale.

Analysis of Variance↗
PubMed2005

[Direct bone morphogenetic protein 2 gene therapy for repairing segmental radial defect in rabbits].

OBJECTIVE: To study the effect of direct bone morphogenetic protein 2 (BMP-2) gene therapy mediated by adenovirus on repairing bone defect. METHODS: The radial defect models were made on 60 rabbits, which were evenly divided into 4 groups randomly. The 4 groups were treated with different materials: group A, adenovirus carrying BMP-2 gene (Ad-BMP-2) plus bovine cancellous bone (BCB); group B, reconstructed BMP-2 plus BCB; group C, Ad-Lacz plus BCB; and group D, only BCB scaffolds. The X-ray, histological examination, biomechanics analysis, and immunohistochemical staining were made 4, 8, and 12 weeks after the operation. RESULTS: Group A gained better effect in the volume of new bones, the anti-bending intensity of the healing bone, and the expression of BMP-2 than those of group B. The defect in group A was healed. No new bones were observed in group C and group D. CONCLUSION: Direct BMP-2 gene therapy is easy to perform and has very strong osteo-induction ability. It is a good method to repair segmental bone defects.

Adenoviridae↗
PubMed2005

[Structure and ecological environmental efficiency of urban forestation].

It is proposed that a new pattern of forestation, arbor-shrub-lawn composite construction, based on analyzing the form and the actual state of the urban forestation. The arbor-shrub-lawn is superior by comparing with the urban lawn as for ecological environmental function including landscape. It is suggested that forestation's ecological saving efficiency and management, maintaining and reducing cost should be thought over simultaneously.

China↗
PubMed2005

[Phosphorus and sulphur bio-cycling in alpine tundra ecosystem of Changbai Mountains].

The study with compartment model on the phosphorus (P) and sulphur (S) bio-cycling in alpine tundra ecosystem of Changbai Mountains showed that the total storage of P and S was 16 088.6 t and 26 079.4 t, of which, 46.14 t and 64.82 t was in vegetation pool, 89.63 t and 53.16 t in litterfall pool, and 15952.8 t and 26014.6 t in soil pool, respectively. The above- and below-ground vegetation pool stored 21.88 t and 44.21 t, and 24.28 t and 20.61 t of P and S, respectively, and the above-ground vegetation pool had 47.4% of P and 68.2% of S in the vegetation subsystem. The transferable P amount was 24.25 t x yr(-1) through plant absorption and 31.59 t x yr(-1) through litterfall return, while the transferable S amount was 31.18 t x yr(-1), 10.12 t x yr(-1) and 21.06 t x yr(-1) in the aboveground plant, belowground root system, and litterfall return, respectively. The natural return ratio of S was 67.5%.

China↗
PubMed2004

Cloning and functional expression of invertebrate connexins from Halocynthia pyriformis.

Unlike many other ion channels, unrelated gene families encode gap junctions in different animal phyla. Connexin and pannexin genes are found in deuterostomes, while protostomal species use innexin genes. Connexins are often described as vertebrate genes, despite the existence of invertebrate deuterostomes. We have cloned connexin sequences from an invertebrate chordate, Halocynthia pyriformis. Invertebrate connexins shared 25-40% sequence identity with human connexins, had extracellular domains containing six invariant cysteine residues, coding regions that were interrupted by introns, and formed functional channels in vitro. These data show that gap junction channels based on connexins are present in animals that predate vertebrate evolution.

Amino Acid Sequence↗