Sex differences in mechanomyographic responses to voluntary isometric contractions

PURPOSE: This study was designed to compare mechanomyography (MMG) and the force relationship during isometric ramp contractions of biceps brachii muscles in females and males to identify sex differences in the MMG responses. METHODS: Subjects (10 females and 9 males; age range, 20-26 yr) were asked to exert an isometric elbow flexion torque from 5 to 80% maximal voluntary contraction (MVC) at a constant rate of 10% MVC per second. The MMG signal was normalized to muscle cross-sectional area (CSA) as measured by ultrasound imaging. RESULTS: MVC and CSA were significantly different between the two sex groups (males>females); however, there was no sex difference in the MVC relative to muscle CSA (MVC/CSA). The root mean squared amplitude of the MMG (RMSMMG) was significantly greater in the male group than the female group. The RMSMMG relative to muscle CSA was also different between the two sex groups (males>females). The sex difference in the RMSMMG/CSA was more pronounced with increasing torque. The torque levels at which the inflection points in the MMG amplitude were located were different between the two sex groups. The mean power frequency (MPF) of the MMG in the female group increased monotonously, which was different from that in the male group. CONCLUSION: Our results suggest that the sex differences in MMG responses and motor unit (MU) activation strategy result from the predominant activity of the MU with slow-twitch fibers and an effective fused tetanus in females. In addition, the sex-related differences in muscle morphology, subcutaneous adipose tissue, and muscle stiffness appear to be insufficiently reflected in the present MMG responses, particularly relative to muscle CSA.     

Ovarian cancer--a comparison between CT diagnosis and serum tumor markers

In 40 patients undergoing pre-treatment for an ovarian tumor, a CT scan of the pelvis and measurements of their CA 125, CA 19-9, IAP (immunosuppressive acidic antigen), and TPA (tissue polypeptide antigen were performed. The specificity and sensitivity of the CT diagnosis was found to be better than any of other tumor markers measurements. Comparison of the 4 markers showed that the CA 125 testing had the greatest sensitivity in detecting an ovarian cancer. Moreover, the sensitivity of CA 125, was better than a combination of the 4 markers. Thus, a CT scan still remains necessary for the diagnosis of an ovarian cancer.     

A clinical study of recombinant human G-CSF in gynecological tumor patients with neutropenia due to chemotherapy (rG.CSF Clinical Study Group)]

We evaluated clinical efficacy of recombinant human granulocyte colony stimulating factor (rG-CSF), successfully expressed in Chinese hamster ovarian cell, in gynecological tumor patients (pts) with neutropenia due to chemotherapy (CT). Fifty-eight pts with advance or relapsed gynecological malignancy were entered into this study. These pts had neutropenia below 1,000/cmm by CT and in the next cycle of CT they were treated with daily rG-CSF (2 micrograms/kg/day, subcutaneously) starting from the next day of CT for 14 days. The activities of rG-CSF were evaluated using following indices calculated for each cycle: a) the absolute neutrophil count (ANC) at nadir, b) the period for restoration in ANC above 1,500/cmm, and c) the total area below the 1,000/cmm level in ANC calculated by a computer. Forty-seven out of 52 evaluable pts (90.4%) showed good response to rG-CSF. Only adverse events considered possibly due to rG-CSF were transient fever and anorexia, one case each. In conclusion, rG-CSF appears to be well tolerated by gynecological tumor patients and to considerably rescue them from neutropenia caused by intensive chemotherapy.     

Clinical features of a newly recognized type of lattice corneal dystrophy

We examined five patients with an undescribed type of lattice corneal dystrophy. All patients were in the seventh to ninth decades of life and had developed decreasing vision late in life. None of the patients had suffered from recurrent epithelial erosions, there was no overt evidence of systemic amyloidosis, and the lattice lines were much thicker than those usually observed in lattice corneal dystrophy types I and II. Available pedigree data from two families of three patients indicated that the corneal disorder affected several siblings but not the parents or offspring. Two patients had no affected family members. There was no known consanguinity in any of the four families.     

Histopathologic and immunohistochemical findings in gelatinous drop-like corneal dystrophy

A cornea with gelatinous drop-like corneal dystrophy was examined by histochemical and immunohistochemical techniques. Pretreatment of the sections with potassium permanganate did not decrease the staining with Congo red dye. Immunohistochemically, amyloid deposits in the cornea with this disease almost did not stain with antibodies to amyloid protein AA and AA-3. However, the corneal epithelium reacted distinctly with antibodies to amyloid protein AA and AA-3. Cross-reactivity with antibodies to protein AA and serum precursor of protein AA has been reported and protein AA-3 is the synthesized peptide corresponding to the amino acid sequence 37-47 of the human amyloid protein AA molecule. The present study suggests at least that corneal epithelial cells with gelatinous drop-like corneal dystrophy may produce a precursor of amyloid related to protein AA-3.