Lysis by RNK-16 cytotoxic lymphocyte granules. Rate assays and conditions to study control of cytolysis

Dense subcellular granules of cytolytic lymphocytes can mediate rapid lysis of erythrocytes or nucleated cells. The granules contain several different proteases and proteoglycans that regulate cytolysis. We describe a rate assay that we have already used to demonstrate the requirement for serine proteases in granule-mediated lysis. In this assay, 51Cr-labeled erythrocytes are lysed by limiting concentrations of granules from RNK-16 tumor cells. Cytolysis is initiated by the addition of calcium (1 mM final concentration) and stopped at 0.5-1 min intervals by acidification to pH 6.0. The effects of the granule protein concentration, temperature, the concentration of erythrocytes, pH, and the concentration of calcium on the rate of lysis are reported. A preliminary mathematical approach is described and suggested as a means to differentiate 'lag' or activation times from the initial burst of lysis. With this rate assay, we have found four classes of protease inhibitors that block granule-mediated lysis (Hudig et al. (1987) Biochem. Biophys. Res. Commun. 149, 882). The utility of the rate assays is underscored by the observation that reversible protease inhibitors only showed rates of cytolysis whereas irreversible protease inhibitors stopped cytolysis completely. Rate assays are essential for future analyses of the complex physiological regulation of granule-mediated cytotoxicity by proteases, endogenous protease inhibitors and proteoglycans.     

Tendon adaptation to different long term stresses and collagen reticulation in soleus muscle

Leg immobilization with or without soleus muscle denervation was studied in young rabbits. Muscle and tendon were maintained in extension, i.e., in the most lengthened position. Length measurements performed on sarcomeres, muscle fibers and tendon-plus-muscle complexes suggest the following progression in tendon growth rates: normal less than denervated-extended less than innervated-extended. Collagen reticulation was studied as a function of fiber location along these tendons by measuring hydrothermal isometric tension (HIT). Large variations were observed depending on fiber location, and significant modifications were induced by immobilization in extension. The results are discussed in relation to stress as a possible factor controlling collagen maturation in connective tissues.     

Childhood dermatomyositis: clinical course of 36 patients treated with low doses of corticosteroids.

Thirty-six patients with juvenile dermatomyositis, seen consecutively between 1983 and 1996 and treated initially with low doses of corticosteroids (prednisolone 1 mg/kg/day), were studied retrospectively to evaluate their long-term evolution and to identify factors predictive of the functional outcome. After a mean follow-up of 4.9 years, 28 (78%) of the patients were well without functional impairment; five patients had inactive disease but with persisting disabilities; and three patients had active disease despite several years of treatment. Fifteen children (42%) developed dystrophic calcifications which, in five of these patients, interfered with functions. These patients treated for juvenile dermatomyositis with a low dose corticosteroid regimen had an evolution identical to that of the published series of patients treated with higher doses and probably had a better quality of life. The best predictors of good functional recovery and minimal calcinosis were early treatment after the onset of symptoms and low creatine kinase serum level at the time of diagnosis.     

Aortic arch origin of the left vertebral artery

Complications from anterior approaches to the cervical spine are uncommon with normal anatomy. However, variant anatomy might predispose one to an increased incidence of injury during such procedures. We hypothesized that left vertebral arteries that arise from the aortic arch instead of the subclavian artery might take a more medial path in their ascent making them more susceptible to iatrogenic injury. Fifty human adult cadavers were examined for left vertebral arteries having an aortic arch origin and these were dissected along their entire cervical course. Additionally, two radiological databases of CTA and arteriography procedures were retrospectively examined for cases of aberrant left vertebral artery origin from the aortic arch over a two‐year period. Two cadaveric specimens (4%) were found to have a left vertebral artery arising from the aortic arch. The retrospective radiological database analysis identified 13 cases (0.87%) of left vertebral artery origin from the aortic arch. Of all cases, vertebral arteries that arose from the aortic arch were much more likely to not only have a more medial course (especially their preforaminal segment) over the cervical vertebral bodies but also to enter a transverse foramen that was more cranially located than the normal C6 entrance of the vertebral artery. Spine surgeons who approach the anterior cervical spine should be aware that an aortic origin of the left vertebral artery is likely to be closer to the midline and less protected above the C6 vertebral level. Clin. Anat. 30:811–816, 2017. © 2017Wiley Periodicals, Inc.     

Anatomical and functional results of McCall culdoplasty in the prevention of enteroceles and vaginal vault prolapse after vaginal hysterectomy

The objective of the study is to evaluate the anatomical and functional results of the McCall culdoplasty in the treatment of moderate hysterocele and the prevention of enterocele and vaginal vault prolapse after vaginal hysterectomy. Using a modified McCall procedure, 185 patients underwent vaginal hysterectomy for mild or moderate uterine prolapse. Pre- and post-operative assessments were carried out using the International Continence Society staging system. The 24-month follow-up showed stable 89.2% incidence of stage 0 vaginal vault prolapse (point C) and a 10% incidence of stage 1 vaginal vault prolapse that was well tolerated and did not require revision surgery. Functional analysis showed satisfactory sexual function at 24 months post-surgery for 81.2% of patients. The McCall culdoplasty did not lead to a disruption of the vaginal axis and gave excellent anatomical and functional results in maintaining support after vaginal hysterectomy, especially in sexually active patients.     

La parturition de Lucy,chemin vers l’extinction ?

ObjectivesTo compare pelvic cavities in australopithecines, modern humans and non-hominid primates in order to discuss the obstetrical mechanisms in australopithecinesMaterial and methodsBony pelves from fossil material (Australopithecus afarensis AL 288-1, Australopithecus africanus Sts14, Australopithecus Stw 431 and Mh2), 133 modern humans (82 adult females and 51 adult males) and 67 anthropoid primates (36 gorilla, 26 Pan troglodytes, 5 Pongo pygmaeus) were reconstructed and compared (shape and morphometric analysis) using 16 pelvimetric mesasurements.ResultsPelves of australopithecines were characterized by lower anteroposterior (AP) and transverse (TRV) diameters in inlet pelvis than in other species. Index (AP/TRV) of pelvic inlet, midpelvis and pelvic outlet in the australopithecines were the lowest (< 100) and the pelvic shape was platypelloid. A logarithmic factorial analysis showed that the pelvic morphology of australopithecines was different from humans and non-hominid primates but nearer the humans.Discussion and conclusionIn contrast with apes where obstetrical mechanics seem to be easier, and because of platypelloidy, mechanism of birth in australopithecines was as difficult as in modern homo sapiens. Birth without cesarean was probably possible in an asynclitic TRV orientation.