Haptoglobin phenotypes in dementia of the Alzheimer type

Previous investigations of the association of haptoglobin (Hp) with dementia of the Alzheimer type (DAT) have reported contradictory results. In the present study, we phenotyped 69 patients clinically diagnosed as having DAT and, for comparison, 64 cognitively intact individuals. We failed to find a significant association between either of the Hp alleles and DAT. Instead, we observed a nonsignificant decrease in the Hp-1 gene frequency in the DAT population (0.34) as compared to our normal elderly comparison group (0.41).

Expression of organ-specific antigens on capillary endothelial cells

Our central thesis is that the endothelial cells which line capillaries of various organs are not all alike. Using monoclonal and conventional antibodies we demonstrate that capillary endothelial cells express on their cell surface an array of antigens that manifest organ selectivity. Brain-derived endothelial cells possess brain-associated antigens, ovary-derived endothelial cells share antigenic markers with other ovarian cells, and lung-derived endothelium possesses antigens that are primarily expressed on cells of the lung. Our experiments lead us to suggest that organ-associated determinants on the endothelial cell surface may play a role in the selective adhesion of tumor cells during metastasis, in site-limited vascular pathology, and in the regionally limited release of angiogenesis-induced factors.

Orthostatic effect of imipramine and doxepin in depressed geriatric outpatients

Blood pressure measurements were collected from 36 depressed geriatric outpatients (ages 55 to 81 years) enrolled in a double-blind, placebo-controlled study of the efficacy of doxepin and imipramine. Mean systolic postural changes were 25.9 mm Hg for imipramine, significantly higher than the 10.5 mm Hg for doxepin, and 12.4 mm Hg for placebo. The orthostatic drop in the imipramine group was only weakly related to dose and did not correlate with amount of pretreatment orthostatic hypotension or with duration of treatment. The increased orthostatic hypotension occurred early in treatment and at low doses of imipramine. Accordingly, caution is advised in the use of imipramine for the elderly.

Separation of aerobic glycolysis from oxidative metabolism and contractility in rat anococcygeus muscle

The relationship of aerobic glycolysis (JLac) and O2 utilization (JO2) to contractility and the activity of the Na+-K+ pump was investigated in rat anococcygeus smooth muscle. Removal of extracellular potassium concentration ([K+]o) caused an initial increase followed by a decrease in JLac below the resting rate. Restoration of [K+]o caused JLac to increase, and this response, but not the initial one observed in zero [K+]o, was prevented by ouabain. These changes in JLac were not related to contractility, since a similar response was observed in both phentolamine-treated and chemically denervated muscles that exhibited minimal force and no significant changes in JO2. Tension development of innervated muscles incubated in K+-free medium was related to changes in JO2. A logarithmic relationship between JLac and [K+]o suggested that changes in JLac resulted from effects on glucose transport or utilization secondary to changes in the membrane potential. In stimulated muscles JLac and JO2 were both positively correlated with isometric force and were not affected by ouabain. Separation of JLac from JO2 and force production under some conditions supports the hypothesis that a functional compartmentalization of metabolic pathways exists in anococcygeus muscle.

Haptoglobin types and unipolar depression

Haptoglobin (Hp) has been used in association studies with unipolar depression and has led to investigations on the possible association of Hp genotypes with disease. Because of the reported association between the Hp-2 allele and depression we phenotyped 65 elderly patients with unipolar depression and 40 elderly individuals without mental disorders. We failed to find an association between either of the Hp alleles and unipolar depression. The Hp2 gene frequencies for the depressed patients and the comparison group were 0.585 and 0.550, respectively, and these values were not significantly different. Both values were within the gene frequency range reported for Caucasian populations.

Estimating the recombination frequency for the MN and the Ss loci

Linkage analysis of 146 informative families for MN and Ss resulted in an estimate of the recombination frequency greater than previously reported. Our total is 7 recombinant children out of 467 individuals, including 1 confirmed recombinant (retested and HLA-compatible) and 6 not verified. The 95% confidence interval of our estimate of recombination is 0.0033-0.0167. Our results are compared with two earlier studies.

Monoclonal antibody against angiotensin-converting enzyme: its use as a marker for murine, bovine, and human endothelial cells

A monoclonal antibody has been prepared against rat angiotensin-converting enzyme (ACE). By selection for antibody binding to endothelial cells of bovine rather than rat origin we have obtained a reagent that has broad cross-species binding properties and that can at the same time serve as a useful marker for the surface of endothelial cells. The IgM-producing clone that we have established, alpha-ACE 3.1.1, has been grown in ascites form to yield ascites fluid that binds selectively to immobilized ACE at a greater than 1:10,000 dilution. By use of enzyme-linked immunosorbent assays, immunofluorescence histology, and flow cytometry, we have demonstrated the presence of ACE on endothelial cells of murine, bovine, and human origin. By means of a fluorescence-activated cell sorter (FACS-IV) we have been able to selectively isolate viable endothelial cells from a mixture of endothelial cells and fibroblasts. We believe the antibody will be useful not only for the selection and in vitro cultivation of endothelial cells but also as a tool for the identification and pharmacological study of ACE.

Peripheral 6-hydroxydopamine administration in the rabbit (Oryctolagus cuniculus): effects on Pavlovian conditioning

The present experiment studied the effects of 6-hydroxydopamine (6-OHDA) administration and adrenal enucleation on differential classical conditioning of somatic and cardiovascular changes in the rabbit. Heart rate and blood pressure conditioned responses (CRs) were relatively large decreases in rate and slight depressor responses, respectively, which were both attenuated by 6-OHDA administration and adrenal demedullation. Frequency of eye-blink response to the reinforced conditioned stimulus was diminished by sympathetic interference during the middle sessions of conditioning, thus producing a decrement in eye-blink discrimination. Electromyographic CRs, on the other hand, were not affected by peripheral catecholamine reduction. These results are discussed in terms of the role of afferent autonomic feedback in influencing the acquisition of somatomotor behaviors.

Adrenal demedullation and peripheral 6-OHDA administration in the rabbit: effects on body weight, general activity and cardiovascular responsivity

Two experiments were undertaken to determine the effects of systemic 6-hydroxydopamine (6-OHDA) administration and adrenal enucleation on body weight, brain and heart norepinephrine, general activity, and cardiovascular responsivity in the rabbit. 6-Hydroxydopamine produced long lasting, dose related decreases in baseline blood pressure (BP) and in pressor responses following electric shock. Partial reversal of the BP changes was observed in nonenucleated animals tested 20 days after 6-OHDA administration but not in enucleated animals tested 5, 10 or 20 days post-injection or in control animals tested 5, 10 or 15 days after vehicle injection. Although 6-OHDA administration produced transient weight loss and activity decrements, no long term weight or activity changes were observed.

Movements at the hip joint

Movements at the hip joint are first discussed in terms of free movement of the lower limb on the trunk. The biomechanics of standing on one lower limb limited to the situation in the coronal plane are presented. The role of the hip muscles in the upright posture and in the movements at the hip joint during walking on the flat and upstairs and downstairs is described.

Scientific Management of the World Stocks of Tunas, Billfishes, and Related Species

This paper reviews past experience in tuna research and management, and proposes guidelines for the future. The resources discussed include three major groups: the six principal market species of tunas, which are heavily exploited; the billfishes, which are in most cases heavily exploited; and the secondary market species of smaller tuna and tuna-like fishes, which are generally underexploited. A brief review of their nomenclature, biology, and fisheries is given, followed by comments on the condition of the stocks. A discussion of institutional arrangements for the scientific study and management of tuna resources is presented, and such arrangements are examined in the light of problems which might be unique to tuna and tuna-like fishes. These special problems and ways in which they might be handled are considered.

The effects of cortisone acetate on tissue regeneration in the rabbit's ear

Images

The effects of female sex hormones on tissue regeneration in the rabbit's ear

The effects of oestradiol-17β and progesterone on tissue regeneration in the rabbit's ear were investigated. One square centimetre of tissue was excised through the whole thickness of the ear under pentobarbitone anaesthesia, and the rate of replacement, in terms of increase in surface area of the regenerated tissue, was recorded at 7-day intervals up to 49 days. The hormones were administered by subcutaneous injection five times weekly during this period. In females, oestradiol in individual doses of 10 μg/3 kg body weight stimulated regenerative growth significantly; 100 μg had no effect, and 1000 μg was inhibitory. In males, injections of 10 μg oestradiol had no significant effect on regeneration, while 100 μg was inhibitory. Progesterone stimulated regeneration in females at a dose of 100 μg/3 kg body weight, and in both males and females at 1000 μg/3 kg. Tissues were examined at 49 days for changes produced by the experimental regimes, and the effects of 17-oxosteroid excretion during the experimental period were also measured. Liver damage was produced in females by oestradiol at the 1000 μg/3 kg level and in males at the 100 μg dose; in both groups it was accompanied by loss of weight. None of the other treatments had toxic effects. The regeneration blastemata of animals treated with progesterone were better vascularized than either those of the untreated controls or of animals treated with oestradiol. The possible significance of these results is discussed.

The effect of mechanical obstruction on tissue regeneration in the rabbit's ear

Tissue of area 1 cm.2 was excised through the full thickness of both ears of a group of rabbits. The excision site of one ear of each rabbit was blocked with Perspex for a time varying between 7 and 49 days. The other ear was allowed to heal and regenerate normally as a control. The growth of new tissue in the experimental ears was measured after block removal and compared with that of the opposite control ears. The regenerated tissue was also examined histologically for changes produced by blocking. Blocking for any period up to 49 days results in an increased growth rate on block removal. Only blocking for 14 days or less has a permanent stimulatory effect. All other blocking periods investigated (21, 28, 35, 42, and 49 days) were ultimately deleterious. The presence of the mechanical blocking device stops the development of a blastema in the normal position. The blastema cells gather in the uninjured tissue behind the wound edge and take up their normal position once the block is removed. The harmful effect of long-term blocking may be due to reduction of the vascularity of the marginal tissue and subsequently to damage to the blastema. Blocking for 14 days or longer results in deformation of the regenerating elastic cartilage.

The effect of androgens on tissue regeneration

Images

TELEMETERING ELECTROMYOGRAPHY OF MUSCLES USED IN WALKING UP AND DOWN STAIRS

1. Telemetering electromyography has been used to investigate the pattern of activity of certain muscles of the lower limb and back while the subjects walked up and down stairs.

2. During walking up and down stairs each limb has a supporting and swinging phase in each complete step.

3. Walking up stairs revealed the following facts. Firstly, raising the body on to the stair above is brought about by the contraction of the soleus, quadriceps femoris, hamstrings and gluteus maximus; the gluteus medius at the same time prevents the body falling on to the unsupported side. Secondly, the tibialis anterior dorsiflexes the foot during the swinging phase and helps the limb to clear the stair on which the supporting limb is placed. Thirdly, the hamstrings flex the leg at the knee in the early part of the swinging phase and control the terminal part of extension at the knee at the end of this phase. Fourthly, both erectores spinae contract twice in each step and control the forward bending of the body at the vertebral column.

4. Walking down stairs revealed the following. Firstly, the body is lowered on to the stair below by the controlled lengthening of the soleus and quadriceps femoris; the gluteus medius at the same time prevents the body from falling on to the unsupported side. Secondly, the tibialis anterior inverts the foot at the beginning of the supporting phase as the toe is placed on the stair below and dorsiflexes the foot in the middle of the swinging phase. Thirdly, the hamstrings control the extension of the leg at the knee during the middle of the swinging phase. Fourthly, both erectores spinae contract twice in each step and prevent forward bending of the trunk at the vertebral column.