Biomedical subjects

Dong Zhou

Publications and source records attributed to Dong Zhou.

24 records · Page 2Linked to original sources

PubMed2003

[Cerebral ischemic tolerance induced by focal ischemic preconditioning in rats].

OBJECTIVE: To investigate the ischemic tolerance induced by focal ischemic preconditioning (PC) in rats. METHODS: Ten minutes of middle cerebral artery occlusion(MCAO) was used for PC. Different duration of reperfusion (1, 3, 7, 14, 21 and 28 days) was allowed before 2 hours of MCAO followed by 22 hours of reperfusion in SD rats that were divided into the PC group and the PC plus MCAO group, and were compared with the rats of sham-operation plus MCAO group. Neurological scores, infarct volume, brain water content and HE staining were evaluated in each group. RESULTS: PC produced no neurological deficits and TTC-demonstrated infarct. PC reduced neurological deficits significantly caused by 2 h MCAO 1-28 days after PC. Infarct volume was reduced only if PC was performed 1-14 days before MCAO. PC given 3 days before MCAO also decreased brain water content. CONCLUSION: Ten minutes of MCAO was strong enough to induce ischemic tolerance without brain injury. Infarct volume reduction appeared at 1 day and did not vanish until 14 days after PC, but protection against neurological impairment existed at least 4 weeks.

Animals↗

PubMed2002

Clinical effects of topiramate against secondarily generalized tonic--clonic seizures.

OBJECTIVE: Intensive and quantitative evaluation of the duration, intensity and frequency of tonic and clonic signs of secondarily generalized tonic-clonic seizures (GTCS) in patients with pharmacoresistant partial seizures during topiramate (TPM) treatment. METHODS: Thirty patients suffering from refractory partial seizures with secondarily GTCS undergoing presurgical evaluation were randomized into a low dosage (100 mg daily) and a parallel medium dosage (200 mg daily) group of TPM add-on medication (15 patients for each group). Study phases included a 3 days baseline video-EEG phase, a 10 days TPM titration phase without video-EEG and a 3 days TPM dose maintenance phase with video-EEG. During the baseline and the dose maintenance phase seizures were recorded using video-EEG monitoring and the following parameters were measured for each recorded secondarily generalized tonic and clonic signs: duration (lasting seconds), intensity (on a 0-3 scale), frequency (numbers per 24 h). RESULTS: A total of 46 complex partial seizures with secondarily generalized tonic-clonic signs during the baseline phase and 20 during the dose maintenance phase were intensively analyzed. More patients in the medium dosage group than in the low dosage groups were free from secondarily GTCS during the dose maintenance phase (nine vs. two, P<0.05). Intergroup comparison suggested that the duration of all tonic signs decreased more in the medium dosage group computing the reduction from baseline to the dose maintenance phase (P<0.05). There were statistically more significant reductions in the duration and intensity of clonic signs in the medium dosage group (P<0.05). CONCLUSION: TPM has an early dose-dependant effect on secondarily GTCS in patients with pharmacoresistant partial seizures. SHORT COMMUNICATION: The present study intensively analyzed the duration, intensity, and frequency of secondarily generalized tonic and clonic signs in patients with pharmacoresistant partial seizures. The quantitative data suggested that TPM had a robust early inhibitory effect on secondarily generalized tonic-clonic signs; effects were more prominent in the medium dosage group (200 mg daily) than in the low dosage group (100 mg daily).

Adolescent↗

PubMed2002

Influence on ictal seizure semiology of rapid withdrawal of carbamazepine and valproate in monotherapy.

PURPOSE: To quantify changes in ictal seizure semiology during rapid withdrawal of carbamazepine (CBZ) and valproate (VPA) from a monoregimen in presurgical evaluation. METHODS: Therapeutic intensive seizure analysis (TISA) with video-EEG monitoring was used in 33 patients with pharmacoresistant partial epilepsy undergoing complete withdrawal of CBZ (20 patients) or VPA (13 patients) from a monoregimen. Monitoring phases included a 3-day baseline phase, a 3-day rapid antiepileptic drug (AED) withdrawal phase, and another 3-day AED-free phase with AEDs in subtherapeutic levels. Seizure variables as complete processes and their various elements (ictal signs) were analyzed, including duration (seconds), intensity (on a scale of 0 to 3), frequency (number per 3 days), and total duration of seizures and ictal signs in 3 days (seconds). The localization of seizure patterns on ictal EEG recording (EEG seizure onset) and the first appearing clinical ictal phenomena (initial ictal signs) were recorded. RESULTS: A total of 188 seizures in the CBZ group and 57 seizures in the VPA group were investigated. Compared with the baseline phase, the CBZ group showed increases in duration, frequency of seizures, various ictal signs, and secondarily generalized tonic and clonic signs during the following two phases. Significantly increased values of the VPA group were observed in seizure duration and frequency of hypermotoric phenomena during the AED-free phase. More patients in the CBZ group had secondarily generalized clonic signs during the AED-free phase. EEG seizure onset and initial ictal signs showed no obvious changes between study phases. CONCLUSIONS: Withdrawal of CBZ is followed more quickly by an increase of seizure frequency and severity than is the case for VPA withdrawal. Both CBZ and VPA withdrawal influences seizure propagation rather than the seizure-onset characteristics, which speaks in favor of its use in presurgical evaluation.

Adult↗

PubMed2002

[Study of the function of leukocyte adhesion molecules in chronic respiratory diseases].

OBJECTIVE: To study the function of leukocyte adhesion molecules in the pathogenesis of Chronic Obstructive Pulmonary Diseases (COPD) and cor pulmonale, and to evaluate the effect of anti-leukocyte-adhesion therapy for cor pulmonale. METHODS: The positive expression rates of CD(11a), CD(11b), CD(18), CD(54) in peripheral blood were quantitatively analyzed by flow cytometry using monoclonal antibodies in 42 cases of COPD (stable stage), 41 cases of cor pulmonale (stable stage), 24 healthy controls as well as 20 cases of cor pulmonale who had taken huobahua. RESULTS: The expression rates of CD(11a), CD(11b), CD(18), CD(54) in monocytes and CD(11a) in lymphocytes from the COPD group were much higher than those in the control group (P < 0.05). CD(11a), CD(11b), CD(18), CD(54) in neutrophils and CD(11a), CD(18), CD(54) in monocytes, and CD(18) in lymphocytes in the cor pulmonale group were significantly stronger than those in the control group (P < 0.05); whereas the positive expression of CDs was greatly reduced in the cor pulmonale patients who had taken huobahua (P < 0.05). No differences were found in other groups. CONCLUSIONS: Upregulation of CD(11a)/CD(18), CD(11b)/CD(18), CD(54) in monocytes, CD(11a)/CD(18), CD(11b)/CD(18), CD(54) in neutrophils and CD(11a)/CD(18), CD(54) in monocytes in cor pulmonale may promote adhesion of leukocytes with endothelial cells, which may play an important role in the pathogenic process. Huobahua may prevent the development of cor pulmonale by down regulating the expression of CDs.

Aged↗

PubMed2002

[Application of neuroendoscopy in brain surgery].

OBJECTIVE: To investigate the effect of neuroendoscope on surgery. METHODS: 315 patients were treated with neuroendoscope. Endoscopic neurosurgery (EN) was used in 219 patients, endoscope-assisted microneurosurgery (EAM) in 72, and endoscope-controlled microneurosurgery (ECM) in 24. RESULTS: 201 (91.8%) of the 219 patients underwent EN effectively. In 72 patients who underwent EAM there was less retraction during tumor removal and visual control was improved. 21 (87.5%) of the 24 patients underwent ECM effectively. No severe complications were observed. CONCLUSION: Neuroendoscopy can reduce tissue trauma, improve visualization during tumor removal, and reduce complications.

Brain Neoplasms↗

PubMed2002

Multiple suppressor gene p16 of human brain gliomas.

OBJECTIVE: To study the relationship among p16, genesis, and development of brain gliomas. METHODS: We detected the deletion and point mutation of p16 exon 2 by PCR-TGGE. Methylation sensitivity ristriction enzyme polymerase chain reaction was used to detect whether methylation is correlated with happening of glioma. RESULTS: p16 homozygous deletion was detected in 14 of 48 gliomas. No deletions were found in low grade gliomas. Of the 48 gliomas, 5 anaplastic gliomas (WHO grade III) and 9 glioblastomas (WHO grade IV) showed homozygous deletion of exon 2 with a deletion rate of 33.33% (5/15) and 50.00% (9/18) respectively. The mutations of 34 gliomas with p16 positive amplification were detected point mutations in two gliomas, in which one was anaplatic glioma and the other was glioblastoma. Six of the 48 gliomas (12.5%) showed exon1 methylations. CONCLUSIONS: p16 may play an important role in genesis of brain glioma. The main alteration of p16 in brain gliomas was homozygous deletion of exon 2, the methylation of p16 exon 1 was subcardinal, however, point mutation was rare. The deletion of p16 was found especially in high grade gliomas, so we could propose that it may be the late event of tumor occurrence.

Brain↗