Biomedical subjects

M H Carr

Publications and source records attributed to M H Carr.

23 records · Page 2Linked to original sources

PubMed1990

Different mouse mast cell populations express various combinations of at least six distinct mast cell serine proteases.

Mouse serosal mast cells (SMCs) and Kirsten sarcoma virus-immortalized mast cells store large amounts of mast cell carboxypeptidase A and serine proteases in their secretory granules. Secretory granule proteins from 2.6 x 10(6) purified SMCs were separated by NaDodSO4/PAGE, trans-blotted to poly(vinylidine difluoride) membranes, and subjected to amino-terminal amino acid sequencing. Four distinct mast cell serine proteases were identified. With mast cell carboxypeptidase A, these serine proteases comprise the major proteins of mouse SMC secretory granules. Each of the four SMC serine proteases was distinct from the two serine proteases present in mucosal mast cells in the intestines of helminth-infected mice. The secretory granules of a Kirsten sarcoma virus-immortalized mast cell line contained three of the SMC-derived serine proteases and one of the mucosal mast cell-derived serine proteases. Thus, the family of mouse mast cell secretory granule serine proteases has at least six distinct members that can be expressed in different combinations in different mast cell populations.

Amino Acid Sequence↗

PubMed1989

The case for planetary sample return missions. 2. History of Mars.

Principal science goals for exploration of Mars are to establish the chemical, isotopic, and physical state of Martian material, the nature of major surface-forming processes and their time scales, and the past and present biological potential of the planet. Many of those goals can only be met by detailed analyses of atmospheric gases and carefully selected samples of fresh rocks, weathered rocks, soils, sediments, and ices. The high-fidelity mineral separations, complex chemical treatments, and ultrasensitive instrument systems required for key measurements, as well as the need to adapt analytical strategies to unanticipated results, point to Earth-based laboratory analyses on returned Martian samples as the best means for meeting the stated objectives.

Chemical Phenomena↗

PubMedDate not supplied

Prolonged bedrest during pregnancy: does the risk of deep vein thrombosis warrant the use of routine heparin prophylaxis?

This is the first study to assess the risk of clinically apparent DVT in pregnant women placed in the hospital at prolonged bedrest. The outcome is discussed with reference to the risks associated with heparin. Information, including delivery data, length of hospital stay, and discharge diagnoses were extracted from a prospectively collected computerized data bank of all deliveries that occurred over a 5.5-year period at Long Beach Memorial Women's Hospital in Long Beach, California, and at St. Joseph's Hospital in Milwaukee, Wisconsin. One group consisted of all pregnant women who had been hospitalized at prolonged antepartum bedrest, as defined by 3 weeks or more. The other group consisted of the remaining population of women whose deliveries occurred during the same time period. There were 48,525 deliveries during the study period, and 266 (0.5%) women were hospitalized at prolonged antepartum bedrest. The mean number of days in the hospital for these women was 34.6 +/- 14 (range 21-82 days). Of these women, one received prophylactic heparin for a prior history of DVT. There were no cases of DVT in the 265 women who did not receive heparin, risk = 0.0 (CI = 0.00-0.99). Of these 265 women, 234 were hospitalized up to the day of delivery. Of these 234 women, 154 (65.8%) underwent cesarean section and no case of DVT occurred in the postoperative period, risk = 0.0 (CI = 0.0-1.7). Out of the remaining 48,259 women who were not hospitalized at prolonged bedrest, there were 18 cases of clinically apparent DVT, and the longest antepartum hospitalization was 4 days. A conservative risk of complications with prophylactic heparin therapy is 1.0% or greater. Although the risk of DVT in pregnant women hospitalized at prolonged bedrest is not zero, our study indicates that it is very low (< 1.0%). Whereas a risk of DVT of at least 1.0% could warrant heparin prophylaxis, even with 265 patients at prolonged bedrest and 48,525 controls, this risk could not be demonstrated. Using a power analysis with an alpha of 0.05 and a power of 80% to demonstrate this risk, one would need 247 cases and approximately 49,000 controls, which were clearly achieved in this study. In view of the risks associated with heparin, routine antenatal prophylaxis is not recommended unless other risk factors for DVT are present.

Bed Rest↗

PubMedDate not supplied

Combined intravenous and oral pentoxifylline in the treatment of peripheral vascular disease. A clinical trial.

Sixteen patients with severe occlusive vascular disease of the lower extremities were randomised to receive a five day course of combined intravenous and oral Pentoxifylline followed by three months oral treatment only, or identical treatment with a matching placebo. Nine patients received active Pentoxifylline, and 7 placebo, Follow-up by regular clinical examination and haemoreological assessment revealed a marked improvement in claudication distance and an increase in red cell deformability in those receiving Pentoxifylline, there being no change in those receiving placebo. Although both of the above parameters were improved by the treatment, there did not appear to be a direct correlation between red cell deformability and claudication distance in individual patients. A combination of intravenous and oral Pentoxifylline therapy results in an increase in both claudication distance and red cell deformability, but the former may not te a direct consequence of the latter.

Administration, Oral↗

PubMedDate not supplied

A clinical trial of Gingkco Biloba Extract in patients with intermittent claudication.

Thirty-seven patients with stage 2 peripheral vascular disease were randomised to receive a six month course of Gingkco Biloba Extract (Tanakan) or matching placebo. Assessment, by claudication distance, A/B ratio, Doppler ankle pressure response to exercise together with recovery time, and a 10 cm analogue scale (LAS) estimation of maximal pain severity, was performed before treatment, and at 6, 12 and 24 weeks. LAS scores were significantly improved after 24 weeks in patients receiving EgB, but not placebo. Claudication distance was significantly increased by Egb. Although claudication distance also increased in the placebo group, this was not significant. A/B ratio and Doppler ankle responses to exercise did not show any significant change in either group at any time interval, nor did the post exercise recovery time. Gingkco Biloba Extract is a safe and effective method of improving walking distance and reducing pain severity in patients with intermittent claudication, although Doppler studies have failed to suggest any gross improvement in the perfusion of the ischaemic leg.

Double-Blind Method↗