PubMed Health⌕ Search

Biomedical subjects

M Pope

Publications and source records attributed to M Pope.

At least 109 records · Page 6Linked to original sources

Lumbar paraspinal compartment syndrome. A case report with physiologic and anatomic studies.

A 24-year-old man presented with severe low-back pain and paraspinal muscle spasm after exertion. Elevation in temperature, white blood cell count, serum muscle enzymes, and urine myoglobin, as well as computer tomographic evidence of paraspinal muscle edema and necrosis, were present. No etiology could be documented, and the possibility of an acute exertional compartment syndrome was entertained. Subsequently, cadaveric dis-sections indicated that the erector spinae muscles are contained within a well-developed fascial sheath. Continuous slit catheter pressure measurements within this compartment in eight healthy male subjects were subsequently carried out. These indicated a physiologic behavior similar to other known compartments for which compartment syndromes have been described. Variation in intracompartmental pressure occurred as a function of body posture, erector spinae isometric contraction, and active intra-abdominal pressurization. We suggest this patient had a paraspinal compartment syndrome and have described pressure characteristics of this compartment in normal men.

Adult↗

Structural effects in reactivity and adduct formation of polycyclic aromatic epoxide and diol epoxide derivatives with DNA: comparison between 1-oxiranylpyrene and benzo[a]pyrenediol epoxide.

Reaction of 1-oxiranylpyrene (1-OP) with DNA and the structures of the covalent and noncovalent complexes formed were studied in aqueous media (5 mM phosphate buffer with 0.1 M NaCl, pH 7) by utilizing the techniques of absorption, fluorescence and linear dichroism spectroscopy in order to gain an understanding of possible structure-activity relationships for polycyclic aromatic hydrocarbon epoxides in tumorigenesis and carcinogenesis, and the results were compared with those obtained for the highly active benzo[a]pyrene diol epoxide (BaPDE). Like BaPDE, 1-OP undergoes acid-catalyzed hydrolysis with the pseudo-first-order rate constant k = 4.6 X 10(-4) s-1 in the absence of DNA, which is about 10 times slower than in the case of BaPDE. In DNA solutions, this hydrolysis is catalyzed by a rapid formation of a physically bound complex of 1-OP-DNA, which subsequently undergoes either (1) hydrolysis to a diol derivative or (2) formation of a covalent adduct of 1-OP-DNA. The same value of the noncovalent binding constant (K = 4000 M-1 is obtained for both 1-OP and for BaPDE, which suggests that the pi-electron interaction between the pyrenyl moiety and the nucleic acid bases is the dominant factor in the formation of the physical complexes and that the two extra OH groups in BaPDE do not play a significant role in determining the value of the physical binding constant.(ABSTRACT TRUNCATED AT 250 WORDS)

7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide↗

Vascular and cellular changes in the decidualized endometrium of the ovariectomized mouse following cessation of hormone treatment: a possible model for menstruation.

Ovariectomized mice were prepared for decidualization with oestrogen and progesterone and arachis oil injected into the uterine lumen. Hormone injections were then stopped and uteri examined at intervals between 31 and 84 h after the last progesterone injection. At 31 and 35 h the stroma showed a normal decidual reaction. Between 45 and 79 h the stroma underwent a series of changes which started with the congestion of dilated blood vessels with swollen erythrocytes followed by breakdown of the vessel walls and extravasation of blood. At the same time the decidual cells showed typical apoptotic changes and there was invasion by leucocytes. An outer ring of stroma did not take part in the degenerative process and eventually a central core of blood cells and degenerating decidual cells became detached and was shed into the lumen. Animals treated in exactly the same way but with the omission of the decidual stimulus did not show such changes in the stroma. It is suggested that the changes in the endometrium resemble those of menstruation and support the suggestion that for menstruation to occur the stroma must be differentiated for implantation. This occurs during the cycle in women but does not occur in non-primates unless a decidual stimulus is applied to the uterus.

Animals↗

The backbone and side chain conformations of the cyclic tetrapeptide HC-toxin.

A study of the conformational parameters of HC-toxin and its diacetyl derivative in chloroform solution has been carried out. Two-dimensional NMR spectroscopy and the nuclear Overhauser effect have been used in order to determine connectivities (assignments and sequence) and approximate torsion angles and interproton distances. The results are consistent with a bis-gamma-turn conformation previously reported for dihydrochlamydocin. Model building based upon NMR data supports a D configuration for Ala2 and Pro4 residues.

Magnetic Resonance Spectroscopy↗

Strain measurement in the medial collateral ligament of the human knee: an autopsy study.

A strain transducer was developed which employs a magnetic field sensing device to detect linear displacement. The transducer was attached to the medial collateral ligament (MCL) of human autopsy specimens, minimally influencing their physiologic behavior. A strain 'map' of the MCL as a function of knee flexion (full extension to 120 degrees) both with and without abduction force was obtained. Our investigation revealed consistent differences in the strain patterns between proximal, middle and distal segments of the anterior and posterior borders of the MCL. Anatomic variations in the pattern of collagen fibers within the MCL, interactions between posterior oblique capsular fibers and the MCL, and the skeletal configuration may account for these varied strain patterns.

Humans↗

Transcutaneous muscle stimulation to retard disuse atrophy after open meniscectomy.

Immobilization of an extremity inevitably results in disuse muscle atrophy. The effectiveness of transcutaneous muscle stimulation by a portable device in preventing atrophy has been determined. Ten patients treated by open meniscectomy and given the usual isometric training were matched with ten patients in whom electrostimulation, consisting of a strong, tetanizing, five-second sustained muscular contraction about 400 times/day, was used for two weeks. Muscular strength and leg circumference were measured before surgery and four weeks after surgery. The electrically stimulated group had a significantly smaller loss of muscle volume and muscle strength, were able to walk earlier without crutches, had a greater range of knee motion, had much less postoperative knee swelling, and used significantly less pain medication. Transcutaneous electrical stimulation may prevent muscle atrophy due to immobilization, thereby shortening rehabilitation time.

Adult↗

An example of a naturally occurring anti-cE (Rh27) that binds complement.

A serum sample from a nontransfused male containing anti-Rh27 and an additional weakly reacting antibody was investigated. One absorption of the serum with RZR1 cells left only anti-Rh27 while repeated absorption with R1R1 cells or autologous cells had no effect. Treatment of the serum with reducing agents destroyed all activity suggesting the antibody was predominantly IgM. Tests with monospecific antiglobulin reagents in the indirect antiglobulin test revealed very weak reactions with anti-IgM and anti-IgA, no reactions with anti-IgG, and strong reactions with anti-C3(C3c + C3d) and anti-C4. This is the first reported example of a naturally occurring complement binding anti-Rh27.

Absorption↗

Transcutaneous muscle stimulation as a method to retard disuse atrophy.

Thirty healthy, young adults (18 to 25 years of age), were volunteers in a three-group study to determine the efficacy of transcutaneous electrostimulation as a means of preventing atrophy of normal musculature on wearing a long-leg cast. Each group of ten subjects (five males and five females) were chosen by lot: Group I, nonisometric, Group II, isometric, Group III, TMS electrostimulated thigh and calf muscles. There was little difference in the findings in Groups I and II, and each lost an appreciable amount of muscle mass and power after just two weeks of immobilization. However, in the electrostimulated group muscle atrophy was one-half that of the other groups in the thigh area and one-fifth that of the others in the calf area. In addition, the calf musculature retained its bulk and power with actual increase in a few of the less athletic individuals. Trancutaneous muscle stimulation offers great promise for surgically treated or impaired extremities, enabling early return to activity with optimal function.

Adolescent↗