Studies on the pathogenesis of ischemic cell injury. V. Morphologic changes of the pars convoluta (P1 and P2) of the proximal tubule of rat kidney made ischemic in vitro

In summary, we have described the time course of changes of mitochondria following ischemia of the kidney proximal tubule. The sequence of morphological changes of matrix as well as inner membrane corresponds well with certain functional or physical parameters such as swelling, respiration, substrate metabolism, acceptor control and P/O ratio. This indicates that morphological parameters can be utilized to predict the functional alterations of mitochondria following ischemia in cells. The significant mitochondrial changes are early loss of granules (15-30 min) and condensation (15 min), swelling (30 min), appearance of fluffy densities (30 min) and flocculent densities (after 60 min), degeneration of cristal structure (240 min) and disintegration of mitochondria as structural units (24 h).     

Syphacia muris: water permeability of eggs and its effect on hatching

The thermal copolymerization of lysine with other alpha-amino acids has been studied further. The identity of the second amino acid influences various properties of the polymer obtained, including the proportion of alpha and epsilon linkages of lysine. A review of linkages in proteinoids indicated alpha and beta linkages for aspartic acid, alpha and gamma linkages for glutamic acid, alpha and epsilon linkages for lysine, and alpha linkages for other amino acids. Thermal proteinoids are thus more complex in types of linkage than are proteins.     

Hypogeusia and zinc depletion in chronic dialysis patients

Dialysis patients generally have a poor appetite, do not enjoy eating, and complain of food, particularly protein, as being disagreeable. Twenty dialysis patients with the above symptoms were tested for taste acuity, serum zinc (Zn), Zn concentrations in hair samples (intracellular Zn), and daily caloric intake. A double-blind, cross-over study was instituted using a Zn supplement and a placebo. After supplementation with Zn, taste acuity markedly improved in 95% of patients and Zn concentrations in hair increased in 85% of patients. The patients' appetites were improved; the average caloric intake increased by 675 kcal/day, and intolerance to protein diminished. In addition 10 normal control subjects were studied pre- and post-Zn supplementation for fasting blood glucose, serum Zn levels, and hair Zn concentration. Side effects were noted, and these usually correlated with elevated serum Zn levels and were minimized or disappeared with decrease in dosage or cessation of therapy.     

Effects of undrugged partners on scopolamine-induced changes in activity and sociability

One group of 6 rats was injected with saline, one with 1.0 mg/Kg scopolamine (D/D) and two others had half the members in each injected with saline and half with scopolamine (S/D). Each was tested in a 36 X 36 in. open field for 10 min. The frequency of ambulation, rearing, social contacts, and the shortest and perimeter distances between rats were found. The presence of the partners in the S/D groups eliminated most of the scopolamine-induced changes found in the D/D group, showing that the nature of the social environment affects drug-induced changes in activity and sociability.     

Difficulties in delivery, including shoulder dystocia and malpresentations of the fetus

Shoulder dystocia is a true obsteric emergency. It may be suspected in large multiparous women, women who have previously delivered large babies, prolonged pregnancy, women who make poor progress in labor, and when the fetus seems very large to palpation. Women with abnormal pelves should be suspect. More liberal use of cesarean section in these situations will reduce the incidence of shoulder dystocia. It is important to have a carefully considered plan of action if shoulder dystocia does occur. The most helpful and definitive maneuver is extration of the posterior arm. Malpresentations cause acute emergencies mainly because of the associated increased incidence of prolapse of the cord. This possibility should be evaluated immediately when rupture of the membranes occurs. Prompt delivery by cesarean section is the treatment of choice with this complications.     

Light- and electron-microscopic characteristics of artrial smooth muscle cell cultures subjected to hypoxia or carbon monoxide

Smooth muscle cells from the tunica media of piglet aortae grown under hypoxic conditions undergo the following changes: First, they become modified by partial loss of myofilaments and proliferation of organelles, which are characteristics of young primitive cells. Second, an increase in number of pinocytotic vesicles at and below the cell surface, indicating increased extracellular uptake of material, can be detected. This is followed by accumulation of Oil Red O positive intracytoplasmic granules and vacuoles as well as the subsequent formation of mount-like protrusions. The latter consist of a core of extracellular material and necrotic debris covered with a cap of viable cells. A third feature of the cells subjected to hypoxia is a conspicuous rise in the number of lysosomes. This is considered to be a manifestation of a defense mechanism of the cells to remove undesirable material from cytoplasm. Cells exposed to an atmosphere rich in carbon monoxide exhibit basically the same alterations as those grown under hypoxic conditions; however, formation of mound-like aggregates is less prominent, while the rise in the number of lysosomes is more evident than in the hypoxic cells. The above alterations are similar to changes observed in smooth muscle cells of rabbit with experimental atherosclerosis. It is suggested that whereever the arterial smooth muscle cell is subjected to adverse conditions basically the same mechanism, consisting of dedifferentiation, increased permeability and lysosomal defense reaction, takes place.