POSTPARTUM PHLEBECTOMY

Saphenous vein ligation and stripping was performed on 27 patients in the immediate postpartum period without complications. Doing the operation at this time saves time and money. Technically it is easier to do postpartum than during pregnancy, and the patients have less postoperative discomfort than is usual with phlebectomy at other times.     

Transmission of Salmonella montevideo in Wheat by Stored-Product Insects

Sitophilus oryzae (L.), S. granarius (L.), Tribolium castaneum (Hbst.), Oryzaephilus surinamensis (L.), Rhyzopertha dominica (F.), Tenebroides mauritanicus (L.), and Cryptolestes pusillus (Schon.) transmitted Salmonella montevideo from wheat contaminated with 10(6) organisms/g to clean wheat. The insects were fed on the contaminated grain for 21 days and were then transferred to clean grain and allowed to feed for 21 days. They were subsequently transferred to two more samples of clean wheat. All species carried S. montevideo into the initial sample of clean wheat but not into a second or third sample. Progeny of the original insects that developed in the contaminated wheat exhibited less ability than the original adults to contaminate clean wheat. Data indicated that few S. montevideo could be carried by the stored-product insects in large masses of grain.     

Decreased Protein Kinase C Activity During Cerebral Ischemia and After Reperfusion in the Adult Rat

The possible activation of protein kinase C (PKC) during total cerebral ischemia was investigated in the rat. Translocation of PKC activity from the soluble to the particulate fraction was used as an index of PKC activation. There was a drop in the proportion of particulate PKC activity from 30% for controls to 20% by 30 min of ischemia (p less than 0.01). By 20 min of cardiac arrest, there was a 40% decline of the total cellular PKC activity (p less than 0.01). This was not accompanied by an increase in activator-independent activity, a finding indicating PKC was not being converted to protein kinase M. These data suggest that PKC was not activated during ischemia, but rather that ischemia causes a reduction in cellular PKC activity. Translocation of PKC activity to the particulate fraction was not observed in the cerebral cortex or hippocampus of reperfused brain for up to 6 h of recovery following 11-13 min of total cerebral ischemia. The level of total, soluble, and particulate PKC activity in the cerebral cortex was reduced (p less than 0.05), corresponding to the decrease observed by 15 min of ischemia without reflow. A similar decline in activity was also observed in the hippocampus. No increase in activator-independent activity was observed. These data suggest that PKC was inhibited during cerebral ischemia and that this reduced level of PKC activity was maintained throughout 6 h of recovery. We conclude that pathological activation of PKC was not responsible for the evolution of ischemic brain damage.     

Receptor inactivation by dye-neuropeptide conjugates. 3. Comparative binding of dye-neuropeptide conjugates to FMRFamide receptors of Helix aspersa and Loligo pealei

Three neuropeptide analogues of FMRFamide (FMRFa) were covalently attached to a tethered derivative of methylene blue to form dye-neuropeptide conjugates. The comparative binding of the latter to FMRFa receptors was subsequently examined in both Helix aspersa (circumesophageal ganglia) and squid (optic lobe membrane). In Helix, the FMRFa analogue CFMRFamide (CFMRFa) inhibited the specific binding of the FMRFa ligand [¹²⁵I]daYFnLRFa in a dose-dependent manner. Az-CFMRFa, one of the dye-neuropeptide conjugates, also dose-dependently inhibited the specific binding of [¹²⁵I]daYFnLRFa. Moreover, their potencies equaled or exceeded that of FMRFamide. In squid, the binding of CFMRFa and FMRFa was similar. However, the dye-neuropeptide conjugate (IC₅₀ of 14 nM) was about 44-fold less potent than FMRFa. The conjugates were synthesized as part of a study seeking to target and inactivate preselected receptors with heretofore unattainable selectivity and permanence.     

A major difference between the divergence patterns within the lines-1 families in mice and voles

L1 retroposons are represented in mice by subfamilies of interspersed sequences of varied abundance. Previous analyses have indicated that subfamilies are generated by duplicative transposition of a small number of members of the L1 family, the progeny of which then become a major component of the murine L1 population, and are not due to any active processes generating homology within preexisting groups of elements in a particular species. In mice, more than a third of the L1 elements belong to a clade that became active approximately 5 Mya and whose elements are > or = 95% identical. We have collected sequence information from 13 L1 elements isolated from two species of voles (Rodentia: Microtinae: Microtus and Arvicola) and have found that divergence within the vole L1 population is quite different from that in mice, in that there is no abundant subfamily of homologous elements. Individual L1 elements from voles are very divergent from one another and belong to a clade that began a period of elevated duplicative transposition approximately 13 Mya. Sequence analyses of portions of these divergent L1 elements (approximately 250 bp each) gave no evidence for concerted evolution having acted on the vole L1 elements since the split of the two vole lineages approximately 3.5 Mya; that is, the observed interspecific divergence (6.7%-24.7%) is not larger than the intraspecific divergence (7.9%-27.2%), and phylogenetic analyses showed no clustering into Arvicola and Microtus clades.      

Multifactorial diversity sustains microbial community stability

Maintenance of a high degree of biodiversity in homogeneous environments is poorly understood. A complex cheese starter culture with a long history of use was characterized as a model system to study simple microbial communities. Eight distinct genetic lineages were identified, encompassing two species: Lactococcus lactis and Leuconostoc mesenteroides. The genetic lineages were found to be collections of strains with variable plasmid content and phage sensitivities. Kill-the-winner hypothesis explaining the suppression of the fittest strains by density-dependent phage predation was operational at the strain level. This prevents the eradication of entire genetic lineages from the community during propagation regimes (back-slopping), stabilizing the genetic heterogeneity in the starter culture against environmental uncertainty.     

Immunohistochemical localization of irisin in skin,eye, and thyroid and pineal glands of the crested porcupine (Hystrix cristata)

Irisin was first identified in muscle cells. We detected irisin immunoreactivity in various organs of the crested porcupine (Hystrix cristata). In the epidermis, irisin immunoreactivity was localized mainly in stratum basale, stratum spinosum and stratum granulosum layers; immunoreactivity was not observed in the stratum corneum. In the dermis, irisin was found in the external and internal root sheath, cortex and medulla of hair follicles, and in sebaceous glands. Irisin immunoreactivity was found in the neural retina and skeletal muscle fibers associated with the eye. The pineal and thyroid glands also exhibited irisin immunoreactivity.