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D M Ford

Publications and source records attributed to D M Ford.

36 records · Page 2Linked to original sources
PubMed1983

A comparison of vertebral muscle fiber characteristics between human and monkey tissue.

A comparison has been made of the vertebral muscle fiber characteristics between human and rhesus monkey. The main purpose of the experiment was to assess the value of the monkey as an animal model for the study of idiopathic scoliosis involving vertebral muscle influence. Vertebral muscle samples were collected from both clearly defined superficial and deep sites on both sides of the column in the midlumbar region. The material was subjected to routine histological and histochemical techniques. The results show considerable similarities between the deep muscle samples of the two species, but the superficial muscles are significantly different on most of the measurements made.

Adult↗
PubMed1982

Sequence of ossification in human vertebral neural arch centers.

The purpose of the present study is to determine whether ossification of the human vertebral neural arches follows a craniocaudal sequences of development or develops in separate groups from the lower cervical/upper thoracic, upper cervical, and lower thoracic/upper lumbar regions as described by Bagnall et al. (1977b) in a radiographic study. Seven formalin-fixed, two fresh frozen, and six serial-sectioned human embryos and fetuses, ranging in crown-rump length (C-R) from 27 mm to 76 mm, were examined. A procedure adapted by Watson (1977a,b) for in toto staining of whole specimens with alcian blue and alizarin red S for cartilage and bone was used, whereas serial sections were stained with hematoxylin and eosin, or Koneff's stain (1960). The intact specimens demonstrated a vivid deep blue cartilaginous skeleton with differentiated red areas of bone development seen through soft tissues rendered transparent by potassium hydroxide or enzyme clearing. The ossification sequence of the neural arches differed from the conventional craniocaudal descriptions given in anatomical textbooks. Neural arch ossification was found to commence in the lower cervical/upper thoracic regions, quickly followed by a second group in the lower cervical region, and subsequently a third group in the lower thoracic/upper lumbar region.

Female↗
PubMed1982

Sensitization of human lymphocytes in vitro: genetic restriction of secondary T cell responses is dictated by the HLA-DR phenotype of antigen-presenting cells.

Antigen-specific proliferation of human T cells sensitized in vitro was found to be macrophage dependent and HLA-DR restricted. Primary sensitization or secondary restimulation did not occur in the absence of antigen-presenting macrophages. The macrophage requirement for secondary restimulation was restricted by specificities shared between macrophages used for primary sensitization and T cells of the HLA-DR locus. Moreover, the magnitude of the response to antigen appeared to be related to the number of HLA-DR haplotypes shared between antigen-presenting cells in primary and secondary cultures. This observation could be attributed to a clonal response of the T cells with respect to HLA-DR on macrophages. Using HLA-DR 3/5 heterozygous KLH-primed T cells, elimination of cells responsive to antigen-pulsed HLA-DR 3/3 macrophages by thymidine suicide techniques left intact responsiveness to antigen-pulsed HLA-DR 5/5 macrophages. Tp determine whether the genetic restriction was dictated by the HLA-DR genotype of the responding lymphocytes or the HLA-DR phenotype of the responding lymphocytes or the HLA-DR phenotype of the antigen-pulsed macrophages, allogeneic macrophages were used to present antigen in primary culture. After elimination of alloreactive cells, proliferation in secondary cultures was found to be dependent on HLA-DR determinants shared between macrophages used for secondary restimulation and those used in primary sensitization, regardless of the HLA-DR genotype of the responding T lymphocytes.

Antigens↗
PubMed1980

Body mass and sex as determining factors in the development of fever in rats.

1. We have investigated the effect of a single I.P. injection (20 microgram/kg) of bacterial endotoxin on rectal temperature in rats of both sexes and from a wide range of body mass. 2. In male rats, endotoxin produced a monophasic or a biphasic rise in temperature, or a monophasic fall. 3. The extent of the rise in rectal temperature in male rats is related to body mass. There is a statistically significant correlation between body mass and the mean change in temperature measured over 100 min after injection of endotoxin. 4. In the female rats, endotoxin produced a monophasic fall in rectal temperature. The extent of the fall was not significantly correlated with body mass. 5. We suggest that the effect of endotoxin in male rats is determined by the physical relationship between body mass and surface area, because larger animals developed greater fevers. 6. The difference between the effect of endotoxin in male and female rats may have a physiological explanation and may involve differences in susceptibility to cutaneous vasodilation occurring immediately after injection of endotoxin.

Animals↗
PubMed1980

Contrasting roles of 5-hydroxytryptamine and noradrenaline in fever in rats.

1. We have investigated the effects of endogenous monoamine depletion on the development of fever in rats. 2. Fever was produced in rats by a single intraperitoneal injection of Salmonella typhosa endotoxin or leucocyte pyrogen manufactured from ox blood. 3. Depletion of brain 5-hydroxytryptamine (5-HT) by pretreatment with p-chlorophenylalanine prevented the rise in rectal temperature produced both by bacterial endotoxin and by leucocyte pyrogen. 4. On the other hand depletion of noradrenaline (NA) by 6-hydroxydopamine pretreatment resulted in a potentiation of the fever produced by bacterial endotoxin. 5. These results suggest that 5-HT is involved in mechanisms responsible for the rise in temperature during fever and that NA is involved in mechanisms which serve to attenuate the rise.

Animals↗
PubMed1975

The skin of primates. XLII. The skin of the silvered sakiwinki (Pithecia monachus).

The following characteristics indicate that the skin of the silvered sakiwinki (Pithecia monachus, E. Geoffroy, 1812) is not only basically similar to other primitive cebids, but also remarkably close to that of callithricids: a thin epidermis with diminished monoamine oxidase activity; a poorly-developed dermis, paucity of elastic fibers, and scant adnexal blood supply; hair follicles arranged in linear perfect sets; grouped hairs present on the cheek; an absence of glycogen and phosphorylase in most sebaceous glands; apocrine glands present throughout most haired body regions, but totally absent from the dorsum; and poorly-differentiated eccrine glands, confined to volar friction surfaces, which are characterized by unusual glycolytic properties. Other noteworthy cutaneous traits include: concomitant epidermal and dermal pigmentation in the face and scalp; Merkel-like disks in the friction surfaces; moderately well-developed Haarscheibe, associated with large, dorsal guard hairs; small, discrete sebaceous glands throughout the dorsum; a 1:1 ratio of apocrine glands to hair follicles in the facial, gular and anogenital areas; and numerous cholinesterase-reactive nerves around eccrine but not apocrine secretory coils. Although previous comparative studies on the skin of New World monkeys suggest that the systematic designation of two familial taxa is warranted, information regarding five of the fifteen genera which comprise the families Callithricidae and Cebidae is totally lacking. Given that three of these genera (Leontopithecus, Chiropotes and Brachyteles) can no longer be obtained from animal dealers because of exportation laws, the authors were fortunate to acquire representatives of the remaining two genera: Callicebus (titi monkeys) and Pithecia (sakiwinkis). Besides defining cutaneous characteristics common to specific taxa, two earlier works by Hanson and Montagna ('62) and Perkins et al, ('68) also suggested that members of the cebid subfamilies Aotinae and Pitheciinae possess cutaneous traits that bridge an interesting gap with the callithricids. Therefore, the acquisition of these two additional aotine and pithecine genera provided the opportunity to test this hypothesis. The following, therefore, is not just another detailed manuscript regarding the skin of primates. Rather, it is an effort to define the integumental characteristics of the last obtainable New World monkey genera, and to assess those cutaneous signatures which are interfamilially common to both the callithricids and more primitive cebids. Primary emphasis is placed on the genus Pithecia; pertinent findings concerning Callicebus will be incorporated into the forthcoming and final summarization of the phylogenetic significance of the skin of New World monkeys (Perkins, '75).

Acetylcholinesterase↗
PubMedDate not supplied

Paraspinal muscle imbalance in adolescent idiopathic scoliosis.

Twelve muscle biopsy samples were taken at operation for spinal instrumentation from each of seven patients suffering from idiopathic scoliosis (one male and six female patients; mean age 14.3 years). The samples were collected from two specific sites (superficial and deep) on both sides on the vertebral column at the level of the apex of the primary curve and two vertebral levels above and below the apex. The results of this study support and extend the findings of other workers. Not only was a significantly larger percentage of Type I fibers found in multifidus muscle at the apex on the curve on the convex side as other workers have found but also in the superficial muscles above and below the apex of the curve on the convex side. These results present a complex picture of muscle fiber characteristics associated with idiopathic scoliosis.

Adolescent↗
PubMedDate not supplied

The histochemical composition of human vertebral muscle.

This paper describes the ranges of variation of characteristics present in human vertebral muscle. The samples used are from subjects who had a relatively brief history of spinal dysfunction. The samples have been taken in a precise manner and from a specific vertebral level with both sides of the vertebral column being studied including both superficial and deep muscles. These values for typical muscle for the ages investigated now can be used in studies involving abnormal vertebral muscle.

Adenosine Triphosphatases↗