Biomedical subjects

Gang Chen

Publications and source records attributed to Gang Chen.

At least 289 records · Page 16Linked to original sources

PubMed2002

Eight-year follow-up of the 90,000-person Haimen City cohort: I. Hepatocellular carcinoma mortality, risk factors, and gender differences.

In an 8-year follow-up of a prospective cohort study in Haimen City, China, we sought to identify hepatocellular carcinoma (HCC) risk factors in addition to hepatitis B virus (HBV) infection. Two cohorts of adults between ages 25 and 64 years at study entry were followed from 1992-1993 to 2000. The male cohort included 58,545 men, 15.0% of whom were HBV carriers. The female cohort included 25,340 women, 10.7% of whom were HBV carriers. 434,718 person-years of follow-up were accumulated, and 1092 deaths from HCC occurred. The relationship of potential risk factors measured at study entry to HCC mortality was analyzed using Cox proportional hazards models. For males, HCC mortality was significantly associated with HBV infection [relative risk (RR) 18.8; 95% confidence interval (CI), 15.7-22.5], history of acute hepatitis (RR, 2.3; 95% CI, 2.0-2.7), family history of HCC (RR, 2.3; 95% CI, 1.9-2.7), and occupation as a peasant (RR, 1.5; 95% CI, 1.3-1.8). For females, HCC mortality was significantly associated with HBV infection (RR, 33.5; 95% CI, 17.1-65.5) and acute hepatitis history (RR, 4.7; 95% CI, 3.0-7.5). HCC risk was not significantly associated with alcohol consumption, water source, or staple foods in either sex. There was no association with smoking in males, but there was a positive association for females. Environmental and genetic risk factors besides HBV infection play a significant role in HCC mortality in this extremely high-risk population. Gender differences in HCC mortality and known risk factors are substantial and warrant further study. Identification of risk factors amenable to intervention should be a high priority in the prevention of HCC.

Adult↗

PubMed2002

[Role of recombinant human bone morphogenetic protein 2/collagen as an onlay bone graft on adult rat calvarial bone].

OBJECTIVE: To evaluate the bone regenerative potential of recombinant human bone morphogenetic protein 2(rhBMP-2)/collagen on adult rat calvarial bone. METHODS: A tight subperiosteal pocket was produced under both sides of the temporal muscle in rats. rhBMP-2/collagen was implanted in one side and collagen alone was implanted in the other side as control. The rats were sacrificed 2, 4 and 8 weeks after operation. The specimen was harvested and examined histologically. For morphometric analysis, the thickness of the temporal bone of both sides was measured and compared. RESULTS: The rhBMP-2/collagen onlay implant resulted in active bone formation and the augmented bone was connected directly with the original bone, whereas the collagen alone resulted in neither bone nor cartilage production. The ossification process in the rhBMP-2/collagen occurred directly through bone formation, similar to intramembranous ossification. CONCLUSION: rhBMP-2/collagen is an effective material as a biological onlay implant.

Animals↗

PubMed2002

[Distraction osteogenesis for repair of cleft palate: an experimental study].

OBJECTIVE: To observe the repair of cleft palate (CP) bone defect under the application of distraction osteogenesis (DO); to investigate the correction mechanism in thin bone of palatal shelf and to search a possible new treatment approach for repair of CP. METHODS: 14 cats were assigned randomly to 3 groups: (1) Empty control, 2 cats unoperated with euthanasia at the end of 2 weeks; (2) Experimental control, 2 cats underwent 8 mm x 18 mm palatal osteoectomy in saggital direction as the experimental model of CP with euthanasia in 6 weeks; (3) Experimental group, 10 cats were performed the same palatal osteoectomy as group (2), the newly designed and individual manufactured intraoral distractors were fixed to teeth by brackets and to bilateral palate bone across the defect with titanium miniscrews. 4 weeks later the transport disc (TD) osteotomy were performed and gradual distraction was started after 6 days latency period at the rate of 0.4 mm x 2/day till the TD reached the opposite edge of the CP. Roentgenographic, gross meterage and ultrastructural observation were performed 2, 4, 6, 8, 12 weeks after completion of distraction. RESULTS: All the examinations revealed the TD recombination to the opposite bone edge of the CP, simultaneously, the proportional expansion of overlay mucoperiosteal flap was achieved. The bone defect were filled with de move osteogenesis. Roentgenographically, the new bone mineralization was along the DO vector, developed from the bone cut edges bilaterally to the central translucent zone until turned to thin fissure. Comparison of the plaster casts showed no change in the occlusion or dentomaxillofacial framework. CONCLUSIONS: The intraoral distractor is able to get both effective distraction and steady fixation. The examination results suggest that the CP bone and soft tissue defect could be repaired and acheived functional reconstruction under DO, which could be a new treatment approach for repair of CP.

Animals↗

PubMed2002

[X-ray combined with cytosine deaminase suicide gene therapy enhances killing of colorectal carcinoma cells in vitro].

OBJECTIVE: To study the effect of X-ray on gene transfer and the antitumoral effect of X-ray combined with suicide gene therapy on colorectal carcinoma cells. METHODS: Green fluorescent protein (GFP) was seen under fluorescent microscope. GFP gene was used for reporting gene to learn gene transfer efficiency and gene expressing time under the influence of radiation. G418 was used to select cytosine deaminase (CD) positive neoplasm cells and CD gene transfer efficiency was tested by cloning efficiency. Antitumoral effect of X-ray combined with CD and 5-FC on colorectal carcinoma cells was tested by MTT. RESULTS: 4 Gy radiation could improve supercoiled plasmid DNA transfer efficiency for about 2 - 4 times and 30 times for linearized plasmid DNA. The mean durations of GFP gene expression treated with 4 Gy radiation were 14 d for supercoiled plasmid and 21 and for linearized plasmid, while in control group, the time was 12 d. Middle-dose radiation combined with CD and 5-FC could kill 99 percent of colorectal carcinoma cells, while in the control group, 5-FC only killed 15 percent of colorectal carcinoma cells which were transduced with CD gene. CONCLUSIONS: X-Ray combined with suicide gene therapy may be used as a promising method for treating colorectal neoplasm.

Antimetabolites↗

PubMed2002

Approval summary for imatinib mesylate capsules in the treatment of chronic myelogenous leukemia.

PURPOSE: Chronic myelogenous leukemia (CML) results from the breakpoint cluster region-Abl fusion gene product, a tyrosine kinase involved in cell division and apoptosis. Imatinib, an orally administered inhibitor of the breakpoint cluster region-Abl tyrosine kinase, is capable of blocking proliferation and inducing apoptosis in CML cell lines. In this report, we describe the preclinical profile of imatinib and the data submitted in the New Drug Application that led to its marketing approval. EXPERIMENTAL DESIGN: Chemistry manufacturing and controls, animal toxicology, and biopharmaceutical data are described. Results of Phase I and Phase II clinical studies in patients with CML in blast crisis (CML-BC), in accelerated phase (CML-AP), and in chronic phase disease-resistant or intolerant to IFN-alpha (CML-CP) are summarized. The basis for marketing approval and postmarketing commitments by the pharmaceutical company are discussed. RESULTS: Toxicology studies in the rat, dog, and monkey show the hematological, renal, and hepatobiliary toxicity of imatinib. Pharmacokinetic studies in patients with CML demonstrate 98% imatinib bioavailability. The elimination half-lives of the parent drug and the major active metabolite, CGP74588, from plasma are approximately 18 and 40 h, respectively. Approximately 81% of the drug is eliminated in 7 days, 68% in the feces and 13% in the urine. Cytochrome P-450 3A4 is the main enzyme responsible for imatinib metabolism. Phase I and II clinical studies were conducted. The Phase I study, in 83 CML patients, evaluated oral imatinib doses from 25 to 1000 mg/day. Dose-limiting toxicity was not observed. The three Phase II studies, in CML-CP, CML-AP, and CML-BC, enrolled 1027 patients. CML-CP patients received 400 mg/day imatinib, whereas CML-AP and CML-BC patients generally received 600 mg/day imatinib. Primary study endpoints were cytogenetic response rate (CML-CP) and hematological response rate (CML-AP and CML-BC). The cytogenetic response rate for CML-CP patients was 49%. The hematological response rate of CML-AP and CML-BC patients was 63 and 26%, respectively. The most common imatinib adverse events were nausea, vomiting, myalgia, edema, and diarrhea. Elevated liver enzymes and/or bilirubin were reported in 27 patients (2.6%). CONCLUSIONS: On May 10, 2001, imatinib mesylate (Gleevec, formerly known as STI-571 and Glivec), manufactured and distributed by Novartis Pharmaceuticals, East Hanover, NJ, was approved by the United States Food and Drug Administration for the treatment of CML in three clinical settings: CML-BC, CML-AP, and CML-CP. This report summarizes the Food and Drug Administration's review of the New Drug Application.

Antineoplastic Agents↗

PubMed2002

[Study of radiation synovectomy using (188)Re-Sulfide in hemophilic arthritis].

OBJECTIVE: To study the effectiveness of radiation synovectomy with (188)Re-sulfide. METHODS: Twenty rabbit models of joint synovitis were injected intra-articularly with different doses of (188)Re-sulfide from 7.4 to 37.0 MBq. By pathological examination, the effects of (188)Re-sulfide on synovium and cartilage were evaluated. Clinically, 10 joints of 7 cases of hemophilic arthritis with (188)Re-sulfide radiation synovectomy were performed. MRI was taken before and after the synovectomy to evaluate the treatment effects. RESULTS: In rabbit models, when (188)Re-sulfide dose larger than 14.8 MBq, the radiation effect on synovitis was remarkable, including thinning the thickened synovium and reducing the inflammatory cells. When radio-activity dose increased to 37.0 MBq, pathological damage was noted in cartilage. Clinical trial demonstrated that radiation synovectomy by (188)Re-sulfide could reduce the frequencies of intra-articular hemorrhage. MRI showed that edema and villi reduced. CONCLUSIONS: Radiation synovectomy using (188)Re-sulfide is effective on synovitis in hemophilic arthritis.

Animals↗

PubMed2002

Approval summary: imatinib mesylate in the treatment of metastatic and/or unresectable malignant gastrointestinal stromal tumors.

PURPOSE: Imatinib mesylate (Gleevec; Novartis, East Hanover, NJ)is a receptor tyrosine kinase inhibitor approved previously in 2001 by the United States Food and Drug Administration for the treatment of chronic myelogenous leukemia in blast crisis, accelerated phase, or in chronic phase after failure of IFN-alpha therapy. We review herein the clinical profile of this drug and the regulatory review leading to the approval of a supplemental New Drug Application for the treatment of metastatic and/or unresectable malignant gastrointestinal stromal tumors (GISTs). EXPERIMENTAL DESIGN: We discuss the efficacy and side effects of imatinib mesylate in a Phase II trial of 147 patients with metastatic and/or unresectable malignant GISTs, the basis for marketing approval, and postmarketing commitments by the drug's manufacturer. RESULTS: Imatinib was assessed in a single, open-label trial involving one European center and three centers in the United States. Seventy-three patients were randomly allocated to receive 400 mg of imatinib daily, and 74 patients received 600 mg daily. At the study report cutoff date, an objective response was confirmed in 56 patients; the overall response rate for the combined study arms was 38% (95% confidence interval, 30-46%). These responses were all partial responses. There was no statistically significant difference in response rates between the two dose groups. Adverse events included edema, fluid retention, nausea, vomiting, diarrhea, myalgias, skin rash, bone marrow suppression, bleeding, and elevations in aspartate aminotransferase, alanine aminotransferase, or bilirubin. Bleeding into the gastrointestinal tract or intratumoral sites occurred in 7 patients (5%) and was not correlated with thrombocytopenia or tumor bulk. The pharmacokinetics of imatinib in GIST patients were similar to those of chronic myelogenous leukemia patients. CONCLUSIONS: On February 1, 2001, imatinib mesylate was approved by the United States Food and Drug Administration for the treatment of malignant metastatic and/or unresectable GISTs. The recommended dose is 400 or 600 mg daily.

Adenocarcinoma↗

PubMed2002

Morphological changes in canine lungs perfused with modified Euro-Collins solution.

OBJECTIVE: To investigate the structural changes in canine lungs perfused with modified Euro-Collins solution (mECS), thus providing insight into the preservation of the donor lung tissue for transplantation. METHODS: Six dogs were anesthetized and pulmonary perfusion with mECS (4 degrees Celsius) was performed before the lungs were isolated thereafter and stored at 4 to 8 degrees Celsius for 30, 60, 120, 180, 240 min respectively, after which tissue samples of the donor lung were taken for morphological observation with both light and transmission electron microscope. RESULTS: Immediately after reperfusion, the pulmonary tissues exhibited clear and intact structures,showing that mitochondrion swelled slightly in the alveolar epithelial cells (AECs). Mild edema occurred in the alveolar wall and the tissues around the veins at 30 min after preservation, which exacerbated to dilapidation of the alveolar wall and obvious tumefaction of the mitochondrion in the AECs at 60 min. At 180 min, rupture of alveolar wall and emergence of the alveolus was observed at 120 min, and a few pulmonary bullae were formed, the AECs (I) of which presented vacuolar changes in the cytoplasma and mitochondrion, with disappearance of the tiny villus of the AECs (II) at 240 min. CONCLUSION: Within 4 h of preservation in mECS, the pulmonary tissues do not undergo obvious changes as signs of injury, which, however, may not be the case after longer preservation.

Animals↗

PubMed2002

Successful resuscitation by emergency room thoracotomy in a patient in agonal state with hemorrhagic shock resulting from penetrating cardiac injury.

A 23-year-old male patient, who was stabbed in the left chest at the fourth intercostal space leaving a 4-cm wound, was in agonal state with blood pressure of 0/0 kPa when admitted. The patient underwent emergency room thoractomy on stretcher through the left fourth intercostal anterior lateral incision 16 min after injury. The exploration revealed 2 500 ml blood in the plural cavity, 4-cm wound in the pericardium, 2-cm wound in the right ventricle of the heart without asystole, and 5-cm wound in the left upper lobe of the lung. Within 4 min the wound in the heart was sutured with the pericardium as the backing. The patient was discharged with full recovery 8 d after injury.

Adult↗

PubMed2002

[Surgical treatment of constrictive pericarditis: experience in 72 cases].

Our experience with the surgical treatment of constrictive pericarditis in 72 cases is reported. The patients receiving surgical treatment had their cardiac function improved to NYHA class I in 59 cases and class II in 11 cases, and death occurred during the operation in 1 case and after the operation in another case due to myocardial expansion and low cardiac output syndrome, respectively. The key elements to ensure success of the surgeries lie in the extent of pericardiectomy and the time and approaches chosen for the operation.

Adolescent↗

PubMed2002

[Expression of energy metabolism-related genes in myocardial tissues of rats with diabetic cardiomyopathy].

OBJECTIVE: To study the pathogenesis of diabetic cardiomyopathy using DNA microarray. METHODS: Experimental rats were grouped into a diabetic cardiomyopathy and a normal control group. The cDNA probes were prepared by labeling the mRNA extracted from normal tissue and tissue of diabetic cardiomyopathy with Cy3-dUTP and Cy5-dUTP respectively through reverse transcription. DNA microarray were constructed by spotting PCR products of 4 000 rat cDNAs onto a specially treated glass slides, and were then hybridized against the cDNA probes followed by fluorescent signals scanning. RESULTS: The expression of energy metabolism-related genes were lower in the tissues of diabetic cardiomyopathy than in normal tissue. CONCLUSION: The energy metabolism disorder may play an important role in the pathogenesis of diabetic cardiomyopathy.

Animals↗

PubMed2002

[Combined thymoma (AB + B)--pathological diagnosis and clinical significance].

OBJECTIVE: To discuss the pathological and biological characteristic and the clinic-pathological relevance of combined thymoma (AB + B). METHODS: According to the WHO Histological Typing of Thymic Tumors, the clinical features and pathological characteristics of AB + B thymomas were analyzed in a series of 141 thymic epithelial tumors (TET) collected in Shanghai Chest Hospital and analyzed statistically with clinical therapy and follow-up data. RESULTS: Seven cases of type A (5.0%), 48 cases of type AB (34.0%), 14 cases of combined thymoma (AB + B) (9.9%), 9 cases of type B1 (6.4%), 22 cases of type B2 (15.6%), 21 cases of type B3 (14.9%) and 20 cases of type C (14.2%) were classified. The overall postoperative survival data showed highly significant differences amongst the histological subtypes. Combined thymoma (AB + B) showed distinctive histopathological characteristics, their prognostic properties were between A, AB and B1-B3, the differences between them being highly significant (log rank: chi(2) = 48.18, P < 0.001). Seventy-three patients (51.8%) were in stage I, 16 (11.3%) were in stage II, 44 (31.2%) were in stage III, and 8 (5.7%) were in stage IV. The association between histological subtype and invasive stage was significant (chi(2) = 71.3, P < 0.001). Combined thymoma (AB + B) was grouped to grade II thymoma. Thymoma grading has a positive relationship with therapy and prognosis (log rank: chi(2) = 57.49, P < 0.001). CONCLUSIONS: It is proposed that combined thymoma (AB + B) may be named as the borderline thymoma. It has a distinctive histopathological definition and criteria and may be grouped as a subtype of thymoma. Its pathological and biological properties are between benign and malignant thymomas, and have significant differences.

Adolescent↗

PubMed2002

Detection of 2,6-cyclolycopene-1,5-diol in breast nipple aspirate fluids and plasma: a potential marker of oxidative stress.

An high-performance liquid chromatography method with electrochemical detection was developed to quantify both 2,6-cyclolycopene-1,5-diol and lycopene in plasma and breast nipple aspirate fluids (NAF). As an example of the utility of this assay, levels in plasma and NAF of 11 women were examined and compared with levels of 8-isoprostane, a commonly used marker of lipid oxidation. Levels of 2,6-cyclolycopene-1,5-diol and 8-isoprostane were higher in NAF than in plasma, but levels of lycopene were lower in NAF than in plasma. Levels of 2,6-cyclolycopene-1,5-diol in plasma and in NAF were significantly correlated with both lycopene and 8-isoprostane levels. This is consistent with the dependence of 2,6-cyclolycopene-1,5-diol levels on both dietary intakes of lycopene and oxidative stress levels. For the correlations between NAF and plasma, lycopene levels were significantly correlated, whereas 2,6-cyclolycopene-1,5-diol levels were not, indicating that levels of 2,6-cyclolycopene-1,5-diol in NAF are difficult to predict from plasma levels. The high levels of 2,6-cyclolycopene-1,5-diol and 8-isoprostane in NAF are consistent with high levels of oxidative stress in the breast.

Adult↗

PubMed2002

[Molecular mechanism of inhibition of sodium butyrate on activation of tumor associated aromatase promoters].

BACKGROUND & OBJECTIVE: Sodium butyrate, a histone deacetylase inhibitor, can inhibit tumor conditioned medium-induced levels of promoter II and I. 3-specific transcripts. This study was designed to investigate the action of sodium butyrate on promoter II and I. 3 activity, which can be directed to elucidation of local estrogen production in breast cancer. METHODS: Primary human adipose fibroblasts (HAF) treated with MCF-7 breast cancer cell-conditioned medium were used as a cell model system. Promoter II and I. 3 deletion luciferase constructs was transfected into HAF. Western blotting and electrophoretic mobility shift assay were performed to evaluate the effect of sodium butyrate on promoter II and I .3. RESULTS: Breast cancer cell-conditioned medium enhanced phosphorylation of activator transcription factor-2 (ATF-2) which was the main modulatory subtype in CREB/ATF-2 family. The effect of sodium butyrate on aromatase expression in breast tumor fibroblasts was mediated by inhibition of phosphorylation of ATF-2, and hence, the inhibition of binding of a transcriptional complex containing phosphorylated ATF-2, C/EBP beta and CREB binding protein (CBP) to promoter II/I. 3 regulatory region. CONCLUSIONS: Sodium butyrate reduces the level of aromatase mRNA arising from cancer-induced promoter region. The aberrant activation of promoter II and I. 3 in HAF is dependent on the phosphorylation of ATF-2.

Activating Transcription Factor 1↗

PubMed2002

[Distraction osteogenesis for the repair of cleft palate--an ultrastructural study].

OBJECTIVE: The aim of this study was to explore ultrastructural characters of the newly formed bone in the correction of cleft palate (CP) bone defect by distraction osteogenesis (DO). METHODS: The CP experimental animal models (12 cats) were established surgically, and were divided randomly into the experimental group (10 cats), in which the hard palate bone defects were corrected with DO procedure at the rate of 0.4 mm x 2/day. The specimen retrieval with euthanasia was carried out at 2, 4, 6, 8, 12 weeks after completion of distraction. Ultrastructural study was then performed; the experimental control group (2 cats) was kept for 6 weeks before euthanasia without any correction, the other extra 2 cats were used as the negative control. RESULTS: New bone formation appeared in early 2 weeks. Exclusively intramembranous bone formation was observed in all specimens. The remodeling activities were keep observed throughout the period of study, and the bone structure matured gradually till 12 weeks after the completion of DO. No repair was observed in experimental control group. CONCLUSION: The reconstruction of CP bone defect by means of DO could get active intramembranous bone formation and remodeling, which adapted to normal functional activities.

Animals↗

PubMed2002

[Characteristics of BMP expression and X-ray films in distraction osteogenesis for repair of cleft palate--an immunohistochemical and roentgenographic study].

OBJECTIVE: The purpose of this study was to observe the roentgenographic characters of distraction osteogenesis (DO) correction of cleft palate (CP), to study the expression of BMP proportional to fixation period time intervals, and to explore the new bone formation mechanism in Cleft Palate bone shelf. METHODS: 12 cats were used to establish the CP animal model surgically, and then were assigned randomly to (1) Experimental group (12 cats): CP defects were DO repaired at the rate and rhythm of 0.4 mm x 2/day. Specimen retrieval at 2, 4, 6, 8, 12 weeks after completion of distraction, roentgenography and Anti-BMP immunohistochemistry studies were performed; (2) Experimental control group (2 cats): CP defects without any treatment procedures, and (3) Empty control group of 2 cats. RESULTS: Anti-BMP immunohistochemistry study showed positive DAB dye in early 2 weeks and most extensively positive expression of BMP in 4 to 6 weeks. The expression of BMP wore off gradually through 8 to 12 weeks. The roentgenography showed that the newly mineralized bone was developed from the cut bone edges bilaterally to the central transparent zone, and the newly formed bone bridged the defect area completely at the end of the study. The CP bone defect was reconstructed and the distraction gap was filled with de nove osteogenesis. No new bone formation was observed in experimental control group. CONCLUSION: The process of new bone formation in the distraction area is dynamic. Being stimulated primarily, the process was kept highly active till quiescence phase finally. The X-ray examination shows that there is distinctively low roentgenopeque. Nevertheless, roentgenography is so far a very effective and convenient method to evaluate and monitor the DO correction efficiency.

Animals↗

PubMed2002

Clinical comparison of the selective serotonin3 antagonists ramosetron and granisetron in treating acute chemotherapy-induced emesis, nausea and anorexia.

OBJECTIVE: The efficacies of the selective 5-hydroxytryptamine3 (5-HT3) antagonists--ramosetron (0.3 mg) and granisetron (3 mg) in treating acute chemotherapy-induced digestive system dysunction were compared. METHODS: A total of 111 patients were enrolled in a single-blind, randomised crossover study; with data from 98 were used to assess efficacy and data from 110 to assess the safety profile. Ramosetron or granisetron was given intraveneously 15 min befire chemotherpy. RESULTS: The ability of ramosetron to prevent emesis, nausea and anorexia was similar to granisetron during the first 6 h following the administration of chemotherapy, ciplatin or doxorubicin. However, during the first 24 h after chemotherapy, significant differences between ramosetron and granisetron appeared: emetic episode (P = 0.068), nausea (P = 0.006), and anorexia (P = 0.048) remained lower in ramosetron-treated patients. The safety profile of ramosetron was similar to that of granisetron and adverse events in both groups were generally mild and transient. CONCLUSION: Ramosetron is more potent and longer-lasting than granisetron in preventing chemotherapy-induced digestive disturbances.

Adolescent↗

PubMed2001

Changes in adenine nucleotide, SOD and MDA contents and mitochondria ulteractructure during diaphragm fatigue in dogs induced by diaphragm pacing.

OBJECTIVE: To explore the possible mechanisms for the occurrence of diaphragm fatigue induced by diaphragm pacing. METHODS: The phrenic nerve of 8 dogs were exposed and subjected to stimulation with electric pulses emitted by a diaphragm pacemaker to induce diaphragm fatigue models, and the contents of ATP, ADP, AMP and AXP in the diaphragm muscles before and after diaphragm pacing were determined by high-performance liquid chromatography (HPLC). The contents of SOD and MDA were also measured and the morphological alteration of the mitochondria observed with transmission electron microscope. RESULTS: The contents of ATP, ADP, AXP and SOD were found significantly lower but MDA was higher during fatigue than those in normal conditions, while AMP content manifested no obvious change. Some mitochondria in the diaphragm muscles swelled and in a few cases, vacuolar degeneration was observed. CONCLUSIONS: The exhaustion and synthesis disturbance of ATP may explain the generation of diaphragm fatigue, and the reduction of dynamophore and ultrastructural injuries of the cells induced by oxygen free radicals may also contribute to this result.

Journal Article↗