Glandular excision in total glandular mastectomy and modified radical mastectomy: a comparison

Total glandular mastectomy and modified radical mastectomy were compared for the amount of breast tissue remaining after surgery. Multiple biopsies were taken from the anterior chest walls of women following total glandular mastectomy (N = 27) and modified radical mastectomy (N = 28) to try to detect any residual glandular tissue. Regardless of procedure performed, breast tissue was identified histologically in 5 percent of all biopsy specimens (159 and 161, respectively). One of every five operative fields was shown to have glandular elements in at least one of the biopsy sites; the positive biopsies did not form a discernible pattern. The residual breast tissue in each of these patients averaged less than 1 gm. On the basis of this study, modified radical mastectomy and total glandular mastectomy appear to be equally effective in removing most of the breast.     

Initial characterization of sheep T-cell growth factor and its species-restricted activity on human, rat, and mouse cells

Sheep T-cell growth factor (TCGF) was prepared from concanavalin A-activated sheep peripheral blood cells and subsequently characterized by ammonium sulfate precipitation, gel exclusion chromatography, and isoelectric focussing. The TCGF was found in the 60-80% ammonium sulfate fraction and was shown to have an apparent molecular weight of 32,500 and an isoelectric point in the range pI 5.2-5.5. The ability of the sheep TCGF to promote proliferation of activated human, sheep, mouse, and rat cells was compared with that of human TCGF prepared by phytohemagglutinin stimulation of lymphocytes from multiple donors and TCGF prepared from concanavalin A-stimulated rat and mouse spleen cells. Human TCGF was found to act across all species barriers, rat TCGF supported the growth of cells of all species except human, and mouse only promoted the growth of activated mouse and rat cells. Sheep TCGF was unique in being unable to support the growth of any cells except autologous cells.     

Digest: Pursue or ambush? Phenotypic disparity in the carnivore forelimb*

The way an animal moves reveals key aspects of its ecology. Carnivore forelimbs are adapted to their predation style, and the structure of the elbow joint can indicate hunting strategy. In this issue, Figueirido (2018) investigates phenotypic disparity, or morphological variation, in domestic dog breeds, the canid family, and the carnivore order using the elbow joint as an indicator of movement and predatory behavior.     

The functions of the lumbar spine during stepping in the cat

To examine the functional roles played by the lumbar spine during overground stepping, seven adult cats were run in electromyographic (EMG) experiments. Recordings were made bilaterally from mm. iliocostalis, longissimus dorsi and multifidus at a single vertebral level (L₃) and from m. rectus abdominis. Stepping movements were monitored synchronously either by videotape or by high speed cinematography. During alternate use of the hindlimbs (walking and trotting), both epaxial and abdominal muscles were active bilaterally and biphasically. During in-phase use of the hindlimbs (galloping and half-bounding), single bursts of activity were observed. Phasic bursts of activity in rectus abdominus were reciprocal to those of epaxial muscles. Second bursts of activity in either group were noted infrequently. Recordings from the same back muscle at several vertebral levels indicated little difference from these patterns. Movements of the lumbar spine during galloping and half-bounding steps, both angular and linear, are easily correlated with muscle activity patterns. Movements of the lumbar spine during walking and trotting show no particular pattern. Only small angular and linear movements are found. It is concluded that the lumbar spine contributes substantially to step length and limb speed during galloping and half-bounding steps and the epaxial and abdominal musculature may also act as elastic bodies. During walking and trotting steps, the epaxial muscles are proposed to act to stabilize the pelvic girdle to provide a firm base for limb muscles which arise on the pelvis and are synchronously active.