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D J Anderson

Publications and source records attributed to D J Anderson.

At least 361 records · Page 20Linked to original sources
PubMed1987

Effects of soluble products of activated lymphocytes and macrophages (lymphokines and monokines) on human sperm motion parameters.

Experiments were conducted to evaluate the effects of supernatants from activated leukocyte cultures and purified lymphokine and monokine preparations on sperm motion. An automated semen analyzer was used to obtain accurate measurements of several parameters of sperm motion. Supernatants from activated peripheral blood leukocyte cultures significantly decreased sperm motility. In studies of effects of individual lymphokines and monokines, significant antimotility effects were observed when spermatozoa were incubated with the lymphokine gamma-interferon and the monokine tumor necrosis factor. Subnormal fertility may result from defective sperm function caused by lymphokines and monokines elaborated by activated lymphocytes and macrophages residing in the reproductive tracts of infertile men and women.

Colony-Stimulating Factors↗
PubMed1987

Periodontal mechanoreceptors and parotid secretion in animals and man.

Parotid flow was determined in rabbits during feeding. The animals produced more saliva when chewing hard laboratory pellets than with carrots, confirming the findings of Gjörstrup (1980a). We showed that one gland always produced more secretion than the other, and that the dominant gland alternated from side to side with changes in the chewing side. Strain-gauge recordings revealed a remarkable similarity in pattern between mandibular strain and ipsilateral parotid flow. Together, these data suggest that chewing movements and chewing force are involved in the control of parotid secretion. In man, flow rates of parotid saliva collected with a Lashley cup and cannula were recorded. During intermittent clenching on a bite block, we found: (1) a positive correlation between rectified integrated masseter EMG and parotid flow; and (2) that anesthesia of various intra-oral nerves could reduce the flow almost to zero. Crushing a particle of breakfast cereal between two teeth resulted in a reproducible parotid flow which was reduced by infiltration anesthesia around one of these teeth. These data point to the involvement of periodontal mechanoreceptors in the control of parotid secretion in rabbits and man.

Animals↗
PubMed1987

Osteomyelitis in a general hospital. A five-year study showing an increase in subacute osteomyelitis.

We have reviewed 60 patients with primary bone infections; 21 of these (35%) had subacute osteomyelitis, a figure which supports other recent observations that this variant of bone infection is becoming more widespread. In this group open culture and biopsy were necessary in order to exclude bony malignancy, and a raised erythrocyte sedimentation rate proved a useful diagnostic aid. All the patients with acute osteomyelitis or with vertebral infection responded to primary treatment, but five of those with subacute osteomyelitis had recurrences.

Anti-Bacterial Agents↗
PubMed1987

Detection of T8 (suppressor/cytotoxic) lymphocytes in human ovarian follicular fluid.

Clear ovarian follicular fluid and the follicular flush (bloody) of aspirated follicles from 18 women undergoing oocyte retrieval for in vitro fertilization were tested for the presence of T-lymphocyte subpopulations with the use of a panel of monoclonal antibodies in indirect immunofluorescence assay. A sample of peripheral venous blood from each patient was run as a control. There was no difference in the percentage of cells positive for the various markers between bloody follicular fluid (i.e., ovarian blood) and peripheral venous blood. T8-positive (suppressor/cytotoxic) lymphocytes were recovered from all clear follicular fluids; ten of the patients exhibited a dramatically decreased T4/T8 ratio (peripheral blood, 2:1; clear follicular fluid, 1:25; P less than 0.001). These lymphocytes may be involved in the suppression of autoimmune responses directed against ovarian antigens.

Adult↗
PubMed1987

Immunosuppressive effects of danazol in vitro.

The effects of danazol on leukocyte activation in vitro were compared with those of other known immunosuppressive steroids. Danazol at a concentration of 10(-6) M, the systemic level in women taking 600 mg/day, significantly inhibited lymphocyte proliferation in cultures activated by T-cell mitogens (Concanavalin A and phytohemagglutinin) and allogeneic mixed lymphocyte culture (MLC). Comparable immunosuppressive effects were achieved in these assay systems with dexamethasone at a concentration of 10(-8) M, and with cortisol and progesterone at a concentration of 10(-6) M. Physiologic concentrations of estradiol and testosterone did not significantly affect these immunologic test systems. These studies provide evidence that danazol is immunosuppressive. It is possible that immunosuppressive effects contribute to the efficacy of this drug in the treatment of endometriosis and autoimmune disorders.

Analysis of Variance↗
PubMed1986

A bipotential neuroendocrine precursor whose choice of cell fate is determined by NGF and glucocorticoids.

Adrenal medullary endocrine (chromaffin) cells and sympathetic neurons both derive from the neural crest. We have found that the embryonic adrenal medulla and sympathetic ganglia are both initially populated by precursors expressing neural-specific genes. By birth, however, the medulla consists largely of chromaffin cells. In primary culture, the medullary precursors have three developmental fates: in NGF they continue to mature into neurons and survive, whereas in glucocorticoid they either extinguish their neuronal properties and exhibit an endocrine phenotype, or else continue to develop into neurons but then die. These data suggest that, in vivo, the adrenal medulla develops through both the glucocorticoid-induced differentiation of bipotential progenitors and the degeneration of committed neuronal precursors, which have migrated into the gland.

Adrenal Medulla↗
PubMed1986

Immunobiology of complete molar pregnancy and gestational trophoblastic tumor.

The unique curability of gestational trophoblastic tumors may in part be attributable to a host immunologic response. The occurrence of rapidly progressive and fatal choriocarcinoma may be favored by histocompatibility between patients and their partners. However, histocompatibility is not a prerequisite for the development and persistence of gestational choriocarcinoma. The expression of HLA by choriocarcinoma cells in culture is enhanced following incubation with gamma-interferon and this may be of both biologic and clinical significance. Complete molar pregnancy is a complete allograft because all molar chromosomes are of paternal origin. Patients with complete mole are sensitized to paternal HLA antigen which is expressed in molar tissue. Other polymorphic antigen systems including trophoblast-leukocyte common antigens and placental-type alkaline phosphatase are also expressed in molar tissue. We have studied the immunopathology of the molar implantation site to investigate possible humoral and cellular immune responses. The relationships among normal placenta, complete mole and choriocarcinoma are not clearly understood. The pattern of expression of oncofetal antigens in these three gestational tissues may be used to assess trophoblastic differentiation. In studies to date, molar trophoblast has the same pattern of expression of oncofetal antigens as normal placental trophoblast. We will review recent advances in our understanding of the immunobiology of gestational trophoblastic disease and suggest new directions for further research.

Alkaline Phosphatase↗
PubMed1986

Vestibulo-spinal response modification as determined with the H-reflex during the Spacelab-1 flight.

Our laboratory at the Johnson Space Center has employed the H-reflex recorded from the soleus muscle as a method of monosynaptic reflex testing in conjunction with vertical linear acceleration to assess modification of utriculo-saccular function induced through prolonged exposure to microgravity. It was hypothesized that exposure to free fall would reduce the necessity for postural reflexes in the major leg muscles, and that postural modification would reflect a change, not in the peripheral vestibular organs, but more centrally. This postural adjustment would reflect a sensory motor rearrangement where otolith receptor input was reinterpreted to provide an environmentally appropriate response. In addition to the H-reflex (which was the only inflight measurement), vestibulo-spinal EMG from the gastrocnemius, and self-motion reports were obtained in response to a sudden earth vertical fall. Preflight, inflight and postflight motion sickness reports were also recorded, and related to the H-reflex data. The results indicated that early inflight H-reflex amplitude was similar to that recorded preflight, but that measurements obtained later in the flight (day seven) did not show a change in potentiation as a function of the different drop to shock intervals. Immediate postflight H-reflex response in three of the four astronauts tested showed a rebound effect. Postflight gastrocnemius EMG in response to the sudden fall did not show a significant change from preflight values. However, one crewman who was tested early postflight did show an increase in EMG activity in response to the sudden fall. This immediate postflight effect returned to baseline rapidly. Self-motion perception obtained inflight suggested that the early inflight drops were perceived like those preflight. Drops later inflight were described as sudden, fast, hard and translational in nature. Immediately postflight the drops were perceived like those late inflight, and the astronauts said that they did not feel as though they were falling, rather the floor came up to meet them. Post hoc peak H-reflex amplitude, both preflight and postflight was related to inflight space motion sickness.

Humans↗
PubMed1986

Dynamic posture analysis of Spacelab-1 crew members.

Dynamic posture testing was conducted on the science crew of the Spacelab-1 mission on a single axis linear motion platform. Tests took place in pre- and post-flight sessions lasting approximately 20 min each. The pre-flight tests were widely spaced over the several months prior to the mission while the post-flight tests were conducted over the first, second, fourth, and sixth days after landing. Two of the crew members were also tested on the day of landing. Consistent with previous postural testing conducted on flight crews, these crew members were able to complete simple postural tasks to an acceptable level even in the first few hours after landing. Our tests were designed to induce dynamic postural responses using a variety of stimuli and from these responses, evaluate subtle changes in the postural control system which had occurred over the duration of the flight. Periodic sampling post-flight allowed us to observe the time course of readaptation to terrestrial life. Our observations of hip and shoulder position, when subjected to careful analysis, indicated modification of the postural response from pre- to post-flight and that demonstrable adjustments in the dynamic control of their postural systems were taking place in the first few days after flight. For transient stimuli where the platform on which they were asked to stand quickly moved a few centimeters fore or aft then stopped, ballistic or open loop 'programs' would closely characterize the response. During these responses the desired target position was not always achieved and of equal importance not always properly corrected some 15 seconds after the platform ceased to move. The persistent observation was that the subjects had a much stronger dependence on visual stabilization post-flight than pre-flight. This was best illustrated by a slow or only partial recovery to an upward posture after a transient base-of-support movement with eyes open. Postural responses to persistent wideband pseudorandom base-of-support translation were modeled as time invarient linear systems arrived at by Kalman adaptive filter techniques. Derived model parameters such as damping factor and fundamental frequency of the closed loop system showed significant modification between pre- and post-flight. This phenomenon is best characterized by movement of the poles toward increasing stability. While pre-flight data tended to show shoulders and hips moving in phase with each other, post-flight data showed a more disjoint behavior.(ABSTRACT TRUNCATED AT 400 WORDS)

Adaptation, Physiological↗
PubMed1986

Expression of trophoblast-leukocyte common antigens and placental-type alkaline phosphatase in complete molar pregnancy.

The current study was undertaken to determine the localization of trophoblast-leukocyte common antigens and placental-type alkaline phosphatase in complete molar pregnancy with the use of rabbit antiserum and murine monoclonal antibodies in immunofluorescence assays. Trophoblast-leukocyte common antigens were expressed on all normal villous trophoblast (8 to 38 weeks' gestation) and on all complete moles studied. Placental-type alkaline phosphatase was not expressed on villous trophoblast before 20 weeks' gestation in either normal placentas or complete moles. In contrast, there was strong expression of placental-type alkaline phosphatase on villous trophoblast of normal placentas of more than 20 weeks' gestational age. The expression of polymorphic antigens such as trophoblast-leukocyte common antigens and placental-type alkaline phosphatase on molar trophoblast may be important in the immunobiologic features of gestational trophoblastic disease.

Alkaline Phosphatase↗
PubMed1986

Qualitative differences in sperm antibody responses in mice of different inbred strains and sexes.

To better understand the immunogenetic basis and potential pathological consequences of anti-sperm humoral immunity, age-matched female mice of 9 different inbred strains were immunized with syngeneic sperm and were tested for qualitative (specificity) and quantitative (titer) antibody differences by radioimmunoassay, immunofluorescence and immunoblot techniques. All mice developed antisperm antibodies, although titers varied considerably between inbred strains. Antisperm antibodies produced in this study did not cross-react with membrane antigens on thymocytes, brain or immature testicular germ cells. Immunoblot tests identified 17 major sperm antigen bands; this approach also revealed considerable inter- and intra-strain variation in antisperm antibody specificities among female mice. In a parallel study C57BL/6 male mice demonstrated significantly lower antisperm antibody titers and an absence of response to certain sperm antigens in immunoblot tests when compared to age-matched females of the same inbred strain. These findings provide evidence that genetic factors (including sex) interact with environmental (nongenetic) factors in the control of immune responses to sperm antigens.

Acrosome↗
PubMed1986

Metabolism of 14C-estazolam in dogs and humans.

14C-Estazolam (2 mg) administered orally to dogs and human subjects was rapidly and completely absorbed with peak plasma levels occurring within one hour. In humans, plasma levels peaked at 103 +/- 18 ng/ml and declined monoexponentially with a half-life of 14 h. The mean concn. of estazolam in dog plasma at 0.5 h was 186 ng/ml. Six metabolites were found in dog plasma at 0.5 and 8 h, whereas only two metabolites were detected in human plasma up to 18 h. Metabolites common to both species were 1-oxo-estazolam (I) and 4-hydroxy-estazolam (IV). Major metabolites in dog and human plasma were free and conjugated 4-hydroxy-estazolam; the concn. were higher in dogs. After five days, 79% and 87% of the administered radioactivity was excreted in dog and human urine, respectively. Faecal excretion accounted for 19% of the dose in dog and 4% in man. Eleven metabolites were found in the 0-72 h urine of dogs and humans; less than 4% dose was excreted unchanged. Four metabolites were identified as: 1-oxo-estazolam (I), 4'-hydroxy-estazolam (II), 4-hydroxy-estazolam (IV) and the benzophenone (VII), as free metabolites and glucuronides. The major metabolite in dog urine was 4-hydroxy-estazolam (20% of the dose), while the predominant metabolite in human urine (17%) has not been identified, but is likely to be a metabolite of 4-hydroxy-estazolam. The metabolism of estazolam is similar in dog and man.

Administration, Oral↗