Peter Beaconsfield

Effect of Changes in Limb Posture on Peripheral Blood Flow

Venous occlusion plethysmography was used to measure the effect of changes in limb position on the peripheral blood flow. The validity of the method with the limb dependent was investigated, and found to be reliable in the conditions of the experiment. The blood flow in the limb was found to be decreased when it was raised or lowered 45 degrees. At 15 degrees of elevation, the flow was increased. Similar changes were found in recently sympathectomized limbs. The reactions may therefore be regarded as local vascular responses to postural change.

Glucose Metabolism Via The Pentose Phosphate Pathway Relative to Cell Replication and Immunological Response

Glucose Metabolism Via The Pentose Phosphate Pathway Relative to Cell Replication and Immunological Response

Hormonal Changes During Ribose-induced Hypoglycemia

Plasma levels of insulin and human growth hormone (HGH) were measured in healthy adults after oral or intravenous administration of the pentose sugar D-ribose. Increased plasma levels of insulin were recorded after both oral and intravenous ribose; there was no consistent change in plasma levels of HGH after administration of ribose by either route. It is suggested that insulin release occurs at such times and in amounts as may account at least in part for the hypoglycemie effect of this pentose.

Glucose Metabolism via the Pentose Phosphate Pathway Relative to Nucleic Acid and Protein Synthesis in the Human Placenta

A parallelism has been demonstrated between the extent of glucose metabolism via the pentose phosphate pathway and the biosynthesis of nucleic acids in the human placenta during gestation.

CARBOHYDRATE, FAT AND PROTEIN METABOLISM IN THE PLACENTA: A CLINICIAN'S REVIEW

Publisher Summary This chapter presents a clinicians review of carbohydrate, fat, and protein metabolism in the placenta. Molecular transfer across the placenta is more complex than the transfer across other cellular membranes. Placental growth is dependent on protein metabolism. The placenta synthesizes a considerable quantity of proteins for export—peptide hormones, certain globulins, and enzymes—and for home consumption in its own structure and functions. Transfer of proteins may involve passage through several placental cells with or without molecular modification in the process. The marked selectivity of placental transfer has important biological consequences. The immunoglobulins (Ig), as a group, cross faster than alpha globulin and beta globulins. The selectivity of transfer and the active involvement of the placenta in the transfer of all compounds essential for fetal development are dependent on the energy produced by the placenta. One third of the oxygen and glucose provided by the maternal circulation for the conceptus is used to support the metabolism of the placenta. The actual proportion depends on the relative size and respective metabolic activities of the fetus and placenta in different phases of gestation. The fetal liver supplies a small proportion of fetal glucose requirements—the major part coming from maternal glucose via the placenta, which it crosses in accordance with the concentration gradient. It is assumed that lipid formation from glucose is responsible for only a small fraction of placental glucose utilization, and that it contributes only a minor fraction of placental lipids. The larger fat molecules such as lipoproteins and phospholipids do not cross the placenta intact.

AMENORRHEA AND INFERTILITY AFTER THE USE OF ORAL CONTRACEPTIVES

Clinical laparoscopic and radiologic findings in 55 patients refer red because of amenorrhea and infertility following the use of oral contraceptives were compared with ovarian responses in animals which were treated with progestational steroids. Relationship was sought between the length of time the pills were taken previous menstrual history or response to treatment with a view of predicting in which patients these complications might arise. The age range of patients was 19 to 34 years. Infertilty for at least 8 months or amenorrhea for 7 months was present in all. Several combinations of oral contraceptives had been taken and several patients had taken more than 1 preparation. Sequential regimen was used by only 3. Roentgenography of the skull and chest vaginal cytology thyroid function and urinary gonadotropin leve ls were determined for all. Gynecography was performed for 46 patients. Laparoscopy with ovarian biopsy was done for 16. Menstruatio n or pregnancy occurred without treatment in 13; 2 of 4 treated for hypothyroidism menstruated and conceived after 6 months. Roetgenograms were all normal; however there were 15 enlarged smooth and 23 cystic ovaries. Of 31 patients given 50-100 mg of clomiphene daily for 5 days to a maximum of 5 courses 21 menstruated and 12 conceived within 3 months. The other 10 were treated with gonadotropins but only 2 have become pregnant. These results parallel studies in female hooded Lister rats who were treated for 4 months with either norethynodrel chlormadinone or megestrol. 3 to 4 weeks after therapy was discontinued the rats were injected intraperitoneally with 100 IU of pregnant mares serum and 54-56 hours later with 20 IU of human chorionic gonadotrophin to induce superovulation. The ovaries of rats treated with steroid contraceptives were enlarged and had numerous cystic follicles; fertility and release of ova after gonadotropin injection were impaired for at least 7 cycles after discontinuing steroids. Limited initial investigation and prescription of clomiphene is recommended for women suffering from amenorrhea and/or infertility after oral contraceptive use. Laparoscopy is considered for those who do not respond. The value of experimental studies in animals for the assessment of drug responses in humans is emphasized.

MEDICINE ON THE WEST BANK OF THE JORDAN

most surgical registrars-to take one example-have to be pushed hard to leave the wards for a research year. The intelligent student is more able to stand back and take the larger view, and is likely, therefore, to be more aware of and responsive to the patient as a person with problems, than is the less intelligent student who finds the basic mechanics of history-taking and examination more difficult. The more intelligent also tends to work faster and more accurately, and therefore has more time to talk about personal problems and to get to know the patient as a person. I am not suggesting that all take the trouble to do so, and this certainly has to be encouraged. However, the opposite generalisation is certainly false.

Metabolism of the normal cardiovascular wall. IV. Effect of epinephrine and isopropylnorepinephrine.

* Charing Cross Hospital Medical School, London, W.C.2, and Royal Free Hospital Medical School, London, W.C.1. A relation between some of the vascular effects of the sympathomimetic amines and their influence on carbohydrate metabolism has been postulated and the liberation of lactic acid by stimulation of glycolysis has been regarded as of particular importance in this respect 2 However, although there is undoubted evidence that epinephrine releases lactic acid from skeletal muscle both in vivo3 and in vitro,4 the participation of vascular smooth muscle in this response has not been established. The present paper reports the results of a study of the in vivo effects of epinephrine and isopropylnorepinephrine on systemic lactate, pyruvate, and glucose production, and the in vitro action of these amines on the glucose metabolism of arterial smooth muscle in the dog.