OBJECTIVETo explore the adaptive mechanism to hypoxia in skeletal muscle of tibetan antelope.

METHODSTibetan sheep which living at the same altitude (4 300 m) with tibetan antelope and low altitude (1 800 m) sheep as control, the content of myoglobin (Mb) and lactic acid (LA), the activity of lactate dehydrogenase (LDH) and malate dehydrogenase (MDH) in skeletal muscles among three animals were analyzed by spectrophotometer.

RESULTSThe content of myoglobin in skeletal muscle of tibetan antelope significantly higher than that of tibetan sheep and low altitude sheep (P < 0.05). And the content of LA in skeletal muscle of tibetan antelope significantly lower than that of tibetan sheep and low altitude sheep (P < 0.05), activity of LDH and MDH in skeletal muscle was significantly lower and higher respectively than that of tibetan sheep and low altitude sheep (P < 0.05). There was no significant difference between tibetan sheep and low altitude sheep.

CONCLUSIONTibetan antelope may improve their ability to get oxygen under hypoxia by increasing the content of myoglobin in skeletal muscle, and the proportion of aerobic metabolism is high in skeletal muscle, it may be relate that with high myoglobin content in skeletal muscle, we suppose that high myoglobin content in skeletal muscle of tibetan antelope might be one of the molecular basis to adapt hypoxia.

Altitude ; Animals ; Antelopes ; metabolism ; physiology ; Hypoxia ; metabolism ; L-Lactate Dehydrogenase ; metabolism ; Malate Dehydrogenase ; metabolism ; Muscle, Skeletal ; metabolism ; Myoglobin ; metabolism

OBJECTIVE: To observe the degradation of myoglobin in skeletal and cardiac muscles after death and to explore its usefulness in estimation of postmortem interval. METHODS: Human skeletal and cardiac muscles were collected at 0, 4, 8, 12, 24, 36, 48, 60, and 72 hours after death and stored at 25 degrees C. The protein was extracted and examined and analyzed by Western blot and imaging technique. RESULTS: Myoglobin showed a continuously postmortem degradation in both skeletal and cardiac muscles. There was no observed difference in degradation between the two tissues. CONCLUSION Changes in myoglobin degradation could be a useful parameter for estimation of the postmortem interval.
Actins/metabolism* ; Blotting, Western ; Electrophoresis, Polyacrylamide Gel ; Forensic Medicine/methods* ; Humans ; Muscle, Skeletal/metabolism* ; Myoglobin/metabolism* ; Postmortem Changes ; Time Factors

OBJECTIVE: To study the pathological morphological changes for diagnosing the cause of death of extensive soft tissue injury or crush syndrome. METHODS: The tissues were stained by HE and IHC. RESULTS: (1) The Mb positive rate was 60%, 75%, 95% respectively. (2) Both the HSP70 positive rate of hearts and brains were 90%. CONCLUSION (1) The animal model of broad soft tissue injury was established. (2) Accumulated the pathological morphological data for diagnosing the cause of death of extensive soft tissue injury or crush syndrome.
Animals ; Cause of Death ; Crush Syndrome/pathology* ; Forensic Medicine ; HSP70 Heat-Shock Proteins/metabolism* ; Kidney/pathology* ; Myocardium/pathology* ; Myoglobin/metabolism* ; Rats ; Rats, Sprague-Dawley ; Soft Tissue Injuries/pathology*

OBJECTIVE: The sensitivity of heart-type fatty acid binding-protein (H-FABP) in the postmortem diagnosis of myocardial ischemia was explored. METHODS: The changes of H-FABP staining in normal, infarcted and suspected ischemia of myocardial cells were studied by immunohistochemistry. RESULTS: There was no depletion in normal control group, and obvious depletion was observed in myocardial infarcted group. Among 9 suspected myocardial ischemia group, 3 cases showed obvious depletion and 3 cases showed vague depletion for H-FABP, there were obvious depletion of Mb in 4 suspected myocardial ischemia cases and vague depletion in 2 cases for Mb. It is indicated that H-FABP can be used to diagnose early myocardial ischemia. CONCLUSION H-FABP is quite sensitive and useful for the diagnosis of early myocardial ischemia.
Biomarkers/analysis* ; Carrier Proteins/analysis* ; Creatine Kinase/blood* ; Enzyme-Linked Immunosorbent Assay ; Fatty Acid-Binding Proteins ; Humans ; Immunohistochemistry ; Myocardial Ischemia/metabolism* ; Myocardium/pathology* ; Myoglobin/metabolism* ; Sensitivity and Specificity

To investigate the difference between the functions of oxygen uptake in skeletal muscle and living habits of plateau zokor (Myospalax rufescens baileyi) and plateau pika (Ochotona curzoniac), the microvessel densities (MVD) of skeletal muscle of plateau zokor, plateau pika and Sprague-Dawley (SD) rat were measured by immunohistochemical staining; the numerical density on area (N(A)) of mitochondria, and surface density (S(V), external surface area density of mitochondria per unit volume of skeletal muscle fiber) were obtained by stereo microscope technique; mRNA levels of myoglobin (Mb) in skeletal muscle were determined by real-time PCR, and the contents of Mb protein in skeletal muscle were determined by spectro-photometer. The results showed that MVD, N(A) and S(V) of mitochondria in skeletal muscle of plateau pika were significantly lower than those of plateau zokor and SD rat (P<0.05). The mRNA levels of Mb gene in skeletal muscle of plateau zokor and plateau pika were notably higher than that of SD rat (P<0.05). There were significant differences in the contents of Mb among these three species, and plateau zokor and SD rat presented the highest and the lowest value, respectively (P<0.05). The results suggest that even though plateau zokor inhabits in the hypoxia environment, most of its skeletal muscle fiber are red muscle fiber. While most of skeletal muscle fibers of plateau pika are white muscle fibers. This kind of white muscle has low MVD, N(A) and S(V) of mitochondria and less content of Mb compared with the red one, suggesting it obtains most energy from aerobic oxidation. The above-mentioned differences in skeletal muscles may be related to not only the different species, but also the different living habits of these two high altitude species.
Animals ; Hypoxia ; Lagomorpha ; physiology ; Microvessels ; physiology ; Mitochondria, Muscle ; physiology ; Muscle Fibers, Skeletal ; physiology ; Muscle, Skeletal ; blood supply ; physiology ; Myoglobin ; metabolism ; Oxygen ; metabolism ; RNA, Messenger ; Rats ; Rats, Sprague-Dawley ; Rodentia ; physiology

BACKGROUNDMyoglobin is expressed exclusively in striated skeletal muscles and has been implicated in nitric oxide scavenging. Accumulating data suggest a critical role for nitric oxide in both the endogenous and therapeutic angiogenic response to ischemia. A clear role for myoglobin in ischemic skeletal muscle is uncertain. We hypothesized that myoglobin overexpression has an adverse impact on the angiogenic response to ischemia.

METHODSMuscle-specific myoglobin over-expressing transgenic mice (MbTG, n = 11), wild type littermates (WT, n = 23) underwent unilateral femoral artery ligation and excision. Laser doppler perfusion imaging was used to monitor changes in hindlimb perfusion before surgery and weekly after surgery up to 28 days. Tissue ischemia was assessed by a necrosis incidence. Upon termination of the experiment (28 days after surgery), skeletal muscles (gastrocnemius, and tibialis anterior) were harvested, the distal part of the muscle was frozen and embedded for histology study, the proximal part was used either to detect vascular endothelial growth factor (VEGF) level with enzyme-linked immunosorbent assays (ELISA) or to determine the proliferation (proliferating cell nuclear antigen (PCNA)) and apoptosis (Bax, and Bcl-2) condition in ischemic muscle by Western blotting. Capillaries were stained with endothelial phosphate alkaline staining and vascular density was expressed in capillaries/fiber.

RESULTSThe recovery of perfusion in MbTG mice was similar to that of WT mice on day 7 (0.485 +/- 0.095 vs 0.500 +/- 0.084) but was significantly less on day 14 (0.536 +/- 0.086 vs 0.623 +/- 0.077, P < 0.05), day 21 (0.588 +/- 0.082 vs 0.684 +/- 0.068, P < 0.01) and day 28 (0.606 +/- 0.079 vs 0.733 +/- 0.093, P < 0.01). The necrosis incidence was higher in MbTG than in WT (54.5% vs 21.6%). Vascular density was less in MbTG compared with that in WT (gastrocnemius 0.19 +/- 0.08 vs 0.30 +/- 0.08, P < 0.05; tibialis anterior 0.22 +/- 0.11 vs 0.33 +/- 0.04, P < 0.05). With ischemic injury, the VEGF level was increased in both MbTG and WT (45.2% and 20.4%, respectively). Western blotting showed that after hindlimb ischemia the proliferation was similar in both MbTG and WT, however, apoptosis was increased in MbTG relative to WT, shown as more expression of Bax and less expression of Bcl-2.

CONCLUSIONAn increase in expression of myoglobin protein in skeletal muscle reduces the endogenous perfusion recovery following surgically induced hind-limb ischemia.

Animals ; Apoptosis ; genetics ; Blotting, Western ; Cell Proliferation ; Enzyme-Linked Immunosorbent Assay ; Hindlimb ; blood supply ; metabolism ; Immunohistochemistry ; Ischemia ; therapy ; Mice ; Mice, Transgenic ; Muscle, Skeletal ; blood supply ; cytology ; metabolism ; Myoglobin ; genetics ; physiology

OBJECTIVETo study the clinicopathological features of spindle cell rhabdomyosarcoma (SCRMS) in order to differentiate it from other myosarcomas.

METHODSThe clinical features, morphologic and immunohistochemical phenotypes of 8 SCRMSs were analyzed.

RESULTSSCRMS cells were found to be arranged in a fascicular or storiform pattern, in which a number of enlarged plump or polygonal shaped rhabdomyoblasts containing abundant eosinophilic cytoplasm with eccentrically placed enlarged hyperchromatic nuclei were mixed. Immunohistochemical staining results showed that vimentin, MyoD1, desmin, actin, myoglobin were positive in tumor cells, but S-100, plap, AE1/AE3, CK, CD117 negative. The follow-up data showed that four cases had died of the recurrent disease, one still alive and the remain three patients lost follow-up.

CONCLUSIONSpindle cell rhabdomyosarcoma is a rare embryonal rhabdomyosarcoma which occurs in the childhood or adulthood with a poor prognosis, and is frequently presented as a painless mass most frequently involveing the head and neck or cervical area or para-testis site. A combination of MyoD1, desmin and myoglobin immunohistochemical staining is helpful in differential diagnosis.

Adolescent ; Adult ; Child ; Combined Modality Therapy ; Desmin ; metabolism ; Diagnosis, Differential ; Female ; Follow-Up Studies ; Humans ; Male ; Middle Aged ; MyoD Protein ; metabolism ; Myoglobin ; metabolism ; Neoplasm Recurrence, Local ; Retrospective Studies ; Rhabdomyosarcoma, Embryonal ; metabolism ; pathology ; surgery ; Soft Tissue Neoplasms ; metabolism ; pathology ; surgery ; Young Adult