Treatment of trichomoniasis in females with and without gonorrhoea.

46 women with trichomoniasis and gonorrhea were treated with nimorazole (300 mg twice daily for 7 days) and a trichomonal cure rate of 90-2 per cent. was noted. In addition, 53 of 112 patients with trichomoniasis but without gonorrhoea, were treated with metronidazole (200 mg three times a day for 7 days) and 59 with nimorazole (300 mg twice daily for 7 days) in a randomized trial. The cure rates were 96 and 90-5 per cent. respectively. There was no significant difference in the results noted in the two groups. Neither the trichomonal infection itself nor the result of antitrichomonal therapy was affected by antigonococcal therapy (one-day treatment with ampicillin or single-dose therapy with doxycycline). No increase was noted in the frequency of candidiasis after antitrichomonal therapy (in patients without gonorrhoea) or after antigonococcal therapy, but there was substantial variation between consecutive specimens in the prevalence of C. albicans.


Effects of x-radiation on the spinal cord: an experimental study of the morphological changes in central nerve fibres.

The morphological changes in central nerve fibres after irradiation have been studied in the spinal cord of young adult rats exposed to 100-6 000 rad doses of 250 kV x-rays using the technique of single fibre teasing as well as conventional light and electronmicroscopic examination of cord sections. Two groups of degenerative changes were found in myelinated fibres. The first consisted of breakdown of paranodal myelin and nodal widening. These changes were found as early as two weeks after exposure to 500-6 000 rad doses and increased in frequency with dose and time in the first two months after irradiation. Paranodal myelin breakdown was less frequent after two months but nodal widening was more prominent. Increasing numbers of thinly myelinated fibres were found after three months suggesting that paranodal demyelination was followed by remyelination. This early group of changes confined to the myelin sheath provides a possible pathological basis for the self-limited sensory syndrome which sometimes occurs within a few weeks or months of irradiation of the spinal cord in man. The second type of change which was also first detected as early as two weeks after irradiation and which appears to be unrelated to the first, consisted of random Wallerian-type degeneration of fibres of all calibres in the spinal white matter. The number of affected fibres was initially small but increased with time and there was no clear dose relationship. This random fibre degeneration is probably the forerunner of the later-occurring delayed radionecrosis of the spinal cord which other workers have found to occur with a latent period of up to twelve months after exposure to doses exceeding 1900 rads to the rat.


Progressive encephalomyelitis with rigidity.

Two cases of encephalomyelitis are described in which the major clinical manifestation was muscular rigidity and stimulus-sensitive muscular spasms. It is suggested, from pathological evidence, that this rigidity was of spinal origin, and that this disorder is a rare but recognizable entity. Comparison is made with previously reported cases of rigidity of spinal origin, including encephalitis lethargica, and with 'subacute myoclonic spinal neuronitis' and the 'stiff man syndrome.'


Delayed visual perception and delayed visual evoked potentials in the spinal form of multiple sclerosis and in retrobulbar neuritis.

(1) We have used both subjective and evoked potential tests to study cases of multiple sclerosis with no history of retrobulbar neuritis (spinal patients) and compared them with patients with multiple sclerosis who had experienced an attack of retrobulbar neuritis (RBN). We measured the delay of steady-state evoked potentials (EPs) elicited by flicker in the medium-frequency (13-25 c/s) range, by flicker in the high-frequency (30-60 c/s) range, and by pattern-reversal. We also measured the delay in seeing (perceiving) both an increase of light intensity and a decrease of light intensity. (2) The difference between perceptual delays for the left and right eyes (D s) was abnormal when retrobulbar neuritis affected only one eye (22/22 patients) even when acuity and discs were normal. It might be supposed that this perceptual test would be ineffective when both eyes were affected by retrobulbar neuritis. However, the value of D was abnormal in cases of bilateral retrobulbar neuritis (5/5 patients). Probably the principal reason is that demyelination was patchy in the patients studied. For this same reason the difference between perceptual delays for two sites in the visual field (T s) may also be abnormal. In principle the perceptual delay test can be effective even when both eyes are similarly delayed: abnormal values of T were recorded in 5 spinal patients for whom D was normal. (3) Perceptual delays were measured for an extended group of 19 patients suffering from spinal multiple sclerosis. Taking both D and T into account, the perceptual delay test alone picked out 12/19 spinal patients. The perceptual delay test has the advantage over EP tests that it can detect islands of demyelination as small as 3 degrees diameter, and the apparatus is cheap and straightforward to use. (4) Thirteen patients with spinal multiple sclerosis, including 6 with no ocular signs or symptoms, were examined with a battery of two evoked potential and one perceptual test. Ten patients had clearly abnormal visual delays. Results for the remaining 3 were equivocal. Delay tests can reveal visual damage in most patients who have not experienced an attack of RBN as well as in practically all patients who have experienced an attack. (5) Correlations between the results of the various tests were different in spinal patients and in multiple sclerosis patients who had experienced an attack of retrobulbar neuritis. Flicker EPs, pattern EPs and visual perception were all delayed in every RBN patient, whereas for spinal patients different tests could pick up different patients. Flicker EPs picked up 5/13 spinal patients, pattern EPs 6/13, perceptual delay (D) picked up 4/13 and perceptual delay T picked up 7/13. (6) Delay tests divided spinal multiple sclerosis patients into two fairly distinct groups. In one group pattern EPs and perception were delayed; in the other group flicker EPs were delayed. This grouping corresponded to a clinical distinction between long-standing patients with visual signs and recent patients without visual signs...


Aluminium, neurofibrillary degeneration and Alzheimer's disease.

Aluminium is neurotoxic and results in the proliferation of 100 A diameter filaments in the cytoplasm of certain neurons. The aluminium concentration for 7 normal human brains was 1-9 +/- 0-7 SD mug/g dry weight (n = 208 samples). The aluminium content of 585 areas sampled in 10 post-mortem cases of Alzheimer's disease ranging in age from 50 to 88 years, in which the diagnosis was based on the specific histological appearances, revealed an elevated aluminium content in some regions. A range of 0-4 - 107-0 mug/g was encountered and 28 per cent of all regions sampled had concentrations in excess of 4 mug/g. Five of 6 cerebral biopsies from patients with Alzheimer's disease also had elevated aluminium content. In 2 additional Alzheimer's brains with neurofibrillary degeneration restricted to certain anatomical areas, elevated aluminium content was found to be associated with neurofibrillary degeneration and not with senile plaques. Furthermore, elevated aluminium content in multiple cortical regions was not found in 2 vascular dementias of the elderly. While the cytotoxic concentration for human neurons is unknown, the cytotoxic concentration for cat's cerebral neurons appears to lie between 4 and 6 mug/g dry weight.


The neuropathology of progressive rubella panencephalitis of late onset.

The clinicopathological changes in a case of progressive rubella panencephalitis of late onset have been presented. The prominent pathological findings in the brain included diffuse destruction of white matter with perivascular inflammatory cells and gliosis, moderate neuronal loss, numerous amorphous vascular deposits in the white matter and severe generalized cerebellar atrophy. These changes are compared and contrasted with those found in congenital rubella and other latent viral illnesses.


Benign myopathy, with autosomal dominant inheritance. A report on three pedigrees.

Three pedigrees are described in which 28 living siblings suffered from a benign myopathy. The first symptoms were observed around the fifth year of life. The proximal muscles were more involved than the distal muscles, the extensors more than the flexors. Due to a marked paresis of the extensor digitorum communis muscles 22 patients showed a flexion contracture of the interphalangeal joints of the last four fingers. In addition 20 patients showed a flexion contracture of the elbows and 12 patients had a plantar flexion contracture of the ankles. A high incidence of congenital torticollis was found. The histopathological features were non-specific and remarkably uniform and consisted of a marked variation in muslce fibre diameter and a very marked increase of fatty tissue. Light-microscopy and electronmicroscopy did not show any specific structural changes. There was normal distribution of type I and type II fibres, without type-grouping or preferential atrophy of one of the fibre types. Lobulated type I fibres were found in 6 out of 12 biopsies. Post-mortem study of one case did not show any convincing features of a neurogenic disorder. As no relationship could be found between the siblings of the 3 pedigrees as far back as the beginning of the eighteenth century, this myopathy seemed to be a new nosological entity.


Transplantation of central and peripheral monoamine neurons to the adult rat brain: techniques and conditions for survival.

The conditions for survival of transplants of peripheral and central monoamine neurons in the adult rat brain were studied using fluorescence histochemistry. Pieces of the superior cervical ganglion from newborn and adult rats and CNS tissue containing noradrenaline (NA), dopamine (DA) and indolamine (IA) neurons from embryonic, newborn and adult rats were transplanted to various brain sites using different techniques: insertion of the graft by means of a glass rod, by "injection", or by direct implantation of the graft in a resection cavity. Three principally different locations for the graft were tested: within the brain parenchyma in the caudal diencephalon and the caudate nucleus; onto the dorsal surface of the caudate nucleus; and onto the pial covering in the choroidal fissure after removal of the overlying cortex and parts of the hippocampal formation. Attempts were also made to transplant to the dorsal surface of the caudate nucleus or the hippocampus with the aid of an "artificial" vascular bed, achieved by previous transplantation of an iris. Consistent survival of the transplanted central and peripheral neurons was obtained only when the transplant was placed in contact with a vessel-rich tissue, such as the pia in the choroidal fissure or the "artificial" vascular bed. While the majority of the monoamine-containing neurons in the transplants died within the first month after transplantation, a significant number of neurons (up to about 150 in the ganglionic pieces and up to about 500 in the embryonic or newborn CNS pieces) survived for at least half a year in the brain. Survival of transplanted adult central monoamine neurons was not observed. A substantial outgrowth of axons was observed from all types of neurons in their new location. These newly formed fibers formed extensive fiber patterns within the transplant itself, around pia vessels, and within the adjacent brain tissue, above all in the hippocampal formation. The usefulness of the present transplantation technique for the exploration of mechanisms underlying reformation of axonal connections in the adult mammalian CNS is discussed.


Pathways linking L-phenylalanine and 2-phenylethylamine with p-tyramine in rabbit brain.

Concentrations of labeled p-tyramine and 2-phenylethylamine were measured in rabbit brain 10 min after the intraventricular administration of either radioactive amine. In both cases the recoveries of the newly synthesized amine and of the unchanged precursor were significantly increased in animals pretreated with the monoamine oxidase inhibitor pargyline. Significant amounts of both amines were present in rabbit brain 10 min after the intraventricular injection of labeled L-phenylalanine. Pretreatment with pargyline increased their recoveries, whereas alpha-methyldopa (an L-aromatic amino acid decarboxylase enzyme inhibitor, L-AAADI) decreased them considerably, and no significant alteration was found in L-alpha-methyldopa hydrazine (a peripheral L-AAADI) pretreated animals. These results provide evidence for a new biochemical pathway in brain for p-tyramine biosynthesis, with L-phenylalanine (bypassing the formation of L-tyrosine) or 2-phenylethylamine as precursors. The significance and implications of these metabolic routes are discussed, especially considering that p-tyramine itself can be converted to catecholamines.


Effect of temperature on postsynaptic potentials of cat spinal motoneurones.

The effect of spinal cord temperature on excitatory postsynaptic potentials (EPSP) and inhibitory postsynaptic potentials (IPSP) were measured by means of intracellular recordings from lumbar motoneurones of 43 cats. While body temperature and oil bath temperature were maintained between 37 and 38 degrees C, the temperature of the spinal segment under investigation was changed separately in the range between 30 and 42 degrees C. Cooling consistently produced an increase in amplitude and duration of both, mono- and poly-synaptic EPSPs and recurrent and direct IPSPs. Warming caused the opposite effect. The input resistance of the motoneurones was inversely related to the spinal cord temperature, while the latency of action potentials produced by intracellular injection of outward current was directly and exponentially related to spinal temperature. Although the data do not provide a quantitative differentiation of pre- versus postsynaptic temperature effects, they are consistent with the notion that temperature dependent changes on postsynaptic membrane properties contribute to the observed PSP changes. It is further suggested that similar postsynaptic temperature effects may be concerned in temperature sensitivity of proposed specific central neurones.


Changes in multiunit activity and EEG induced by the administration of natural progestins to flaxedil immobilized cats.

The effects of progesterone (P) and 7 of its metabolites on the EEG and multiunit activity (MUA) of various limbic structures were studied in flaxedil immobilized cats. Most progestins inhibited the MUA of the mesencephalic reticular formation, hippocampus and hypothalamus and induced cortical EEG synchronization. MUA changes in the mesencephalic reticular formation frequently preceded EEG synchronization. Progestins reduced in the 5 beta postition (pregnanolone, epipregnanolone and pregnanedion) inhibited neuronal discharge and synchronized EEG activity with shorter latencies and in lower doses than those reduced in the 5 alpha position (allopregnanolone and allopregnanedion). Progestins having the delta 4,3-keto structure (P, 20 alpha-hydroxy pregnenone, 20 beta-hydroxy pregnenone) induced electrophysiological changes with prolonged latencies and in doses significantly higher than ring A reduced progestins. Administration of epipregnanolone to "cerveau isole" preparations depressed neuronal firing in those structures located rostral to the level of the brain stem transection (hypothalamus, hippocampus), but failed to increase the already synchronized cortical activity. These results suggest that: a, ring A reduction increases the capacity of P and other delta 4,3-keto progestins to inhibit neuronal discharge in certain brain areas and b, changes in neuronal firing induced by progestins are not necessarily mediated through the cat brain stem reticular formation.


Systematic examination in the rat of brain sites sensitive to the direct application of morphine: observation of differential effects within the periaqueductal gray.

An extensive mapping of the rat brain (403 sites) ranging from AP +8 to AP -3 revealed that the region showing maximum sensitivity to the intracerebral administration of morphine in the elevation of the nociceptive threshold lay within the periaqueductal gray. Analysis of the distribution of responsive sites indicated that the most active sites, those having the shortest latency of effect, were located within the ventrolateral aspect of the caudal periaqueductal gray. These antinociceptive actions of morphine were observed to be both dose-dependent and reversible by the administration of naloxone. We observed that microinjections of morphine could produce changes in the pinch withdrawal response which were distributed in a crude somatotopic fashion. Injections into the rostral aspect of the periaqueductal gray yielded a block of the pinch response in the rostral portions of the body, whereas such injections into the caudal periaqueductal gray always yielded a whole body analgesia. In the rostral sites, transient ipsilateral blocks of the pinch response were occasionally seen. A pinch block limited to the hind paws alone was never observed. It is suggested that morphine acting through the periaqueductal gray may actuate a potent supraspinal modulatory system related to the transmission of information derived from behaviorally aversive stimuli.


A quantitative autoradiographic and electrophysiological study of the reinnervation of the dentate gyrus by the contralateral entorhinal cortex following ipsilateral entorhinal lesions.

The post-lesion proliferation of contralateral enthorhinal afferents which occurs in response to ipsilateral entorhinal lesions was quantitatively analyzed with autoradiographic and electrophysiological techniques. In both cases, the extent of the crossed projection to the dentate granule cells was quantified on the basis of a contralateral/ipsilateral (C/I) ratio. Autoradiographic measures of grain density in the entorhinal terminal field indicates that the very sparse crossed entorhinal projection in intact animals proliferates approximately 6-fold following unilateral entorhinal lesions (on the basis of an increased C/I ratio of grain density in animals with long standing unilater entorhinal lesions). Furthermore, the total number of grains in the entorhinal terminal zone (obtained by subtracting background from non-terminal regions) also increases approximately 6-fold, indicating that compression of the neuropil cannot be the factor responsible for the increased grain density. These increases in the anatomical extent of the crossed projection as a consequence of unilateral entorhinal lesions are also reflected electrophysiologically. In operated animals, the C/I ratio of the extracellular population EPSP (a measure of the synaptic current generated by the crossed projections) also increase 5-8 fold. In addition, while in normal animals, no population spikes are observed following stimulation of the contralateral entorhinal area (indicating an absence of synchronous grnaule cell discharge in response to contralateral entorhinal input), such population spikes are quite prominent in the reinnervated dentate gyrus, indicating a large increase in the effective synaptic drive of the proliferated crossed projections.


Electrophysiological analysis of the projection from the contralateral entorhinal cortex to the dentate gyrus in normal rats.

The projection from the contralateral entorhinal cortex to the dentate gyrus is shown to exert a monosynaptic excitatory action. Stimulation of the contralateral entorhinal cortex evokes unitary granule cell discharges in the dentate gyrus. This evoked activity is followed by a period of inhibition lasting about 50 msec. Laminar analyses of field potentials generated by contralateral medial entorhinal stimulation localize the synaptic activity to the middle portion of the granule cell dendrites. This localization is consistent with the termination site of the contralateral entorhinal projection as previously shown anatomically. Earlier studies have indicated that the entorhinal cortex excites only the ipsilateral dentate gyrus. These findings now demonstrate that the cortical input to the dentate gyrus is bilateral in normal rats. However, the contralateral projection appears to be much less efficacious than the ipsilateral input.


Discharge patterns of bulbo-pontine respiratory unit populations in cat.

Respiration related units (RRU) were recorded during a stratigraphic exploration of medulla and pons from the cervical junction to the caudal part of the pneumotaxic system in the semi-chronic locally anesthetized 'isolated respiratory centre' of the cat. Metal 'low impedance, capacitance compensated' microelectrodes recorded multi-unit signals from which unitary discharges were discriminated and processed by computer; it is suggested that using these techniques, the sample was a good representation of the total unit population. The phase relation to phrenic discharge was determined on cycle triggered time histograms. Of 23,000 units, 28% had a definite respiratory modulation. Examined individually, each RRU showed a stable discharge pattern corresponding to one of various respiratory types, the majority of which have been described previously. Both temporal and spatial distributions of RRU discharges were analyzed. Temporal distribution of peak firing frequencies (PFF) of 5,000 RRU sampled anatomically at random showed two main populations whose modes were observed during inspiration (I) or expiration (E). Troughs were observed in the histogram at the transition from I to E and E to I, thus indicating low probability for finding phase spanning RRU in the medulla and pons up to the pneumotaxic level. These statistical results turned out to be identical to those obtained with an a priori classification method comparable to that used in most of the previous works. In addition, the PFF distribution suggested that the E population could be further divided into 3 sub-populations whose modes fall in early, mid, and late expiration respectively. Comparison of RRU temporal distribution in two regions, one rostral, another caudal to a frontal Horsley-Clarke plane situated 3 mm in front of the obex, showed that, in the caudal region, 70% of the RRU were I units, while, in the rostral medulla and pons, equal proportions of I and E neurons were found. Temporal distribution of RRU peak frequencies was studied separately in anatomical structures where the probability of finding RRU was high. No clear correspondence between RRU types and anatomy could be found, but marked differences between structures were observed, thus suggesting nevertheless a different spatial distribution for I and E populations.


Three dimensional representation of bulbo-pontine respiratory networks architecture from unit density maps.

Results of the preceding paper32 suggest that bulbo-pontine respiration related units (RRU) could be classed into 4 populations according to the relation of their peak firing frequency to the respiratory cycle: one inspiratory (I) and 3 expiratory (E) (early, mid and late). A further study of their spatial distribution is reported. Recorded units totalling 26,520 were distributed through a matrix of unitary cubes of which about 2,000 were found within the limits of the medulla and pons. Both percentage and density of respiratory and non-respiratory units were estimated in each cube. Statistical analysis of unit distribution showed a high probability of finding RRU in certain regions. The probability of finding I and E units in separate cubes was high, whereas there was no probability better than chance for recording one of the 3 E types separately from the 2 others. Therefore, only two populations, I and E, could be considered for spatial analysis. A thresholding technique applied to I and E unit density figures in unitary cubes demonstrated a definite limit for I and E populations. A computerized, three-dimensional (3-D) reconstruction of the outer surfaces of the I and E networks showed that half a medullary system consisted of 2 contiguous and uninterrupted columns extending from the cervical junction up to the pneumotaxic system. The main body of the I population was found in the caudal third and dorsolateral part of the bulbopontine region, while the main body of the E population was in the middle third in a ventromedial position. Both have caudal and rostral extensions that run parallel to the main axis of the brainstem and give rise to several lateral branches; these lie in close contact and interdigitate extensively, especially in the rostral third of the bulbopontine region. From the outer limits of I and E networks, a progressive increase of unit density levels was observed towards the core; it showed that inside both I and E populations, RRU aggregate into high density foci (HDF). Large HDF were found in the main body of each population. Smaller HDF were observed scattered throughout the medulla; I, and to a lesser extent E, HDF invade and surround sensory and motor nuclei and roots of the branchial nerves.


Acid phosphatase in rat neurohypophyseal dispersions and its fractions enriched for neurosecretosomes and pituicytes after water deprivation and lactation.

Neurohypophyseal dispersions and fractions enriched for neurosecretosomes and pituicytes were prepared from rats subjected to 6 days of water deprivation and 9-10 days of lactation as stimuli of the hypothalamo-neurohypophyseal system (HNS). After water deprivation the content of the fractions changed in such a way that the neurosecretosomes, and to a lesser extent also the pituicytes, accumulated at a lower density within the gradient used for separation. Stimulation by means of lactation did not show such changes when a comparison was made with dioestrus. Microchemical and histochemical tests for acid phosphatase showed that most of the activity in the controls was present in the neurosecretosomes. A rough calculation, which takes into account the different yields for the dispersion elements, showed a rather equal distribution for acid phosphatase activity between axonal and pituicytic compartments of the intact neurohypophysis. The known acid phosphatase activity response of the neural lobe after HNS stimulation, which was also detectable in the dispersion, resulted histochemically in an increased staining intensity for both neurosecretosomes and pituicytes, but with microassay it was distributed along a gradient similar to oxytocin. It was therefore concluded that this lysosomal enzyme response within the neurophypophysis is preferentially localized in the neurohypophysis is preferentially localized in the neurosecretory axons.


Sleep and motor activity of the rat during ultra-short light-dark cycles.

The vigilance states and motor activity of the rat were recorded during ultrashort light-dark (LD) cycles. The LD schedules were the following: 10 min light -- 10 min dark (LD 10:10), LD 7.5:7.5, LD 5:5 and LD 2.5:2.5. With all short LD schedules, paradoxical sleep (PS) and high motor activity occurred more frequently during dark periods than during light. PS and motor activity were rapidly enhanced by darkness and inhibited by light, whereas the percentages of total sleep and slow wave sleep were only gradually decreased during the dark periods and increased during light. Compared to the LD 12h:12h control days, sleep was enhanced by all short LD schedules, an effect that was most marked in the circadian phase of maximum waking (corresponding to the LD 12h:12h dark period). The short LD cycles interacted with an intrinsic sleep cycle, whose period is approximately 10 min. Interval histograms of PS episodes showed that an optimal synchronization of the ultradian sleep rhythm is achieved when the period of the LD cycle or its multiple correspond also to 10 min. It is suggested that the response of PS and motor activity to changes in illumination may be due to common mechanisms.


Methionine supplementation of low protein diets for broiler chicks in the tropics.

In the first experiment, diets containing 14, 16, 18, 20, 22 or 24% protein with no methionine supplementation were tested, while in the second experiment diets containing 16, 18 and 20% supplemented with methionine to give 90, 100 or 110% of the recommended N.R.C. levels were compared with an unsupplemented 24% protein diet. 2. Methionine supplementation of the low protein diets stimulated faster gains than the unsupplemented diets but not enough to surpass the response to the 24% protein control diet. 3. It was concluded that a high protein diet unsupplemented with methionine was more economical to feed to broilers than supplemented low protein diets.


The effect of short heat stress upon leucocyte count, plasma corticosterone level, plasma and leucocyte ascorbic acid content.

Cocks were exposed to 1 or 2 h at 24 degrees C; blood samples were taken before and immediately after treatment and for a period of 20 h thereafter. 2. Heat caused a significant decrease in leucocyte counts, an increase in corticosterone concentration in plasma and an increase of ascorbic acid in plasma and in leucocytes. 3. These four measures can be used to indicate a stress response and the measurements can be done without harming the animal.


Inheritance of body weight and rate of gain in Japanese quail.

The effects of hatch date, location and sex on the body weight and rate of gain in Coturnix coturnix japonica were examined. 2. The data conformed to a mixed and adjustments were made for the fixed effects sex, hatch date and location. Adjustment improved the precision of the estimates by reducing the error variances significantly. 3. Rearing equal numbers of birds from each family at different locations made the interactions negligible. 4. Weight gain was greater if illumination intensity up to 35 d was less. 5. Females were not heavier on the 1st day but were heavier on the 14th and 35th days than males. 6. Variance components and genetic parameters were estimated.


On estimating non-additive genetic parameters in chickens.

Several economically important traits in two Leghorn populations (over 9000 birds) were examined for additive and non-additive components of genetic variance and sex-linked effects. Data were analysed by two different statistical models based on least-squares procedures. 2. Six different covariances were first calculated between relatives; i.e., full-sibs 3/4-sisters, half-sisters, dam-daughters, grandam-granddaughters and aunt-nieces. 3. From the covariances, weighted least-squares equations were used to obtain estimates of variance components for additive genetic, dominance, maternal and sex-linkage effects. 4. The estimates of non-additive components were highly variable but generally small compared with the additive genetic estimates. 5. In general this study suggests that for most traits, with the possible exception of rate of egg production, there is relatively little non-additive genetic variation. 6. The consequences of possible negative correlations between additive effects and maternal effects are considered as they might apply to egg production in poultry.


Method of colostomy and cannulation of the chicken.

A procedure for colostomising birds from 3 weeks to 5 months of age is described. 2. A plastic cannula was inserted into the fistula 10 d after surgery to keep it open. 3. Provided that the cannula was changed regularly at 10-d intervals there was no constipation or dilation of the intestine.


Heritabilities and genetic correlations in related dwarf and normal broiler populations.

Heritability estimates were higher for 8-week body weight in dwarf than in normal broiler populations due to the maternal effects of dwarf dams. 2. The dwarfing gene dw did not induce new genetic variability for egg weight, 30-week body weight and age at sexual maturation. 3. Genetic correlation estimates showed that the selection for 8-week body weight will increase egg weight in dwarf pullets more than in normals. 4. Within a dwarf population it should be possible to increase 8-week body weight without influencing the mature size of pullets.


Direct methods for the analysis of lamellar neutron diffraction from oriented multilayers: a difference Patterson deconvolution approach.

We have described here a direct method for the solution of the phase problem for lamellar neutron diffraction from hydrated oriented multilayers of model membranes. As a result, the neutron-scattering profiles of such model membranes can be uniquely determined. We note that such methods can easily be extended to cases in which the thickness of the water layer w is somewhat greater than d/2 as long as it is substantially less than d [e.g., w less than 3d/4 would suffice, since deltaP(-d/4 less than or equal to x less than or equal to d/4) would contain only contributions from see article without overlapping contributions from see articles and to cases in which isotopic labeling is used instead of partial H2O-D2O exchange.


The structure of carbon monoxide myoglobin: real-space refinement.

The refinement results in optimum positioning of atoms in the density in most cases, and the juxtaposition of positive and negative density leads to high contrast in the maps and rapid convergence of the refinement. The real-space technique is particularly useful in handling the problem of peak overlap, which is difficult in the neutron case. All refinements to date have been done on the original map, which was phased without hydrogen and deuterium atoms, but the next series of refinements will contain H and D atoms, hydrogen exchange information, and structured water molecules. Comparison of the refinements of CO, Mb and met Mb have shown the iron atom to move nearly into the heme plane. No deuterium atom exists to bond the distal histidine to the CO ligand. Atomic coordinates of all atoms and water molecules will be published on completion of the refinements.


Use of the tangent formula for the refinement of neutron protein data.

The tangent refinement technique has been shown to work marginally for protein neutron data, at least to the extent that the images of all atoms except hydrogen are sharpened. However, the process is very sensitive to over-refinement, and all the maps were sharpened excessively. Refinements in the squared structure were more stable, and the maps were somewhat better than those from the original structure refinement. This technique might be helpful in certain instances, but the poor quality of the maps prevents it from being generally useful. Perhaps the tangent refinement technique will be more fruitful in application to neutron protein data when experimental phase information is available.


A neutron television camera detector.

The system under development has a large counting rate capability; this is extremely important where the total background count exceeds the total counts in the signals of interest. Its spatial resolution is of the order of one mm, which is perfectly adequate for neutron work, while the screen size of 400 mm is reasonable. The main limitation of the system is its limited counting efficiency, and this is directly attributable to the optical self-absorption of the neutron phosphor. Any newly developed transparent phosphor with the same light output would immediately change the situation. The success of the electronics hardware in reducing random noise is demonstrated in Figure 3, which shows in the bottom trace the live video output when the input to the system is a grey-scale test chart. The top trace is the output after the image has been digitally integrated. Figures 4 and 5 show the monitor outputs of the see articles x-ray system with a "still" diffraction pattern of a crystal of GPD (glyceraldehyde-3-phosphate dehydrogenase). Figure 4 is a photograph of the "live" video display, and Figure 5 is the digitally summed image. All coherent noise in the system, i.e., all noise synchronized with the TV scans has to be kept lower than the first bit threshold. However, this requirement can be relaxed when dealing with diffraction patterns, such as those from single crystals, for which a local background is subtracted from the pattern.


Fly's eye: a counting camera for thermal neutrons-some applications, problems, and prospects.

An area detector for thermal neutrons based on image intensification techniques has been described. Some capabilities and limitations of the detection system have been discussed. Among the former are high spatial resolution, high instantaneous counting rate, electronic zoom, time-gating, and integration. The detector is limited in that the maximum counting rate for a resolution element is 60 regularly spaced counts per second. Also, the nonuniformity of response over the detector puts a limit on the useful size and necessitates point-by-point calibration. In addition, a higher efficiency for neutron detection would be desirable. Some typical applications of the system are crystal inspection, neutron magnetic diffraction topography, and searches for temperature-induced changes in diffraction patterns. The future application of solid-state television sensors and microchannel-plate intensifiers to improve the system were briefly mentioned.


Investigation of biological macromolecular systems with a pulsed neutron source--a review.

The conclusion that can be drawn on the basis of the above considerations is that investigation of biological macromolecules and crystalline structures by SAS and diffraction of neutrons with the TOF method is feasible. The main difficulties of the TOF method (the wavelength dependence of the incident beam, resolution power, and detector efficiency; the need for their determination and up-to-date values) are compensated for by its advantages. Both methods allow a high data accumulation rate and optimal employment of the incident neutron spectrum. The latter has been achieved by utilizing a dominant part of the Maxwellian spectrum and by a more uniform distribution of statistical accuracy over the most informative measuring range. Another advantage is the high degree of monochronatization of the incident neutron beam by the TOF method. The rigid requirements concerning the data accumulation rate and the capacity of the on-line system computer memory are technical problems but not basic ones.


Some focusing techniques and their application to low-angle neutron scattering.

Both imaging and simple converging collimator systems can provide a focused neutron beam. Each system has been tested and appears suitable for exploitation. Imaging systems employing bent multilayer monochromators can be made simply by elastically bending a flat multilayer. The periodic spacing of the multilayer can be made to match that of the sample. The converging Soller slit provides a purely geometric means of prouducing a focused beam. Wavelength spread and distribution across the beam can be controlled separately. Soller-slit technology is further advanced than that of multilayers. The experiments sketched above demonstrate that converging or focused neutron beams suitable for low-angle scattering work can be produced with existing technology. Focusing incurs little or no loss of intensity and does not seriously distort the resolution function of a low-angel instrument. It permits a small spectrometer to make use of both advanced detector technology and large samples and thus to approach the capability of a much larger machine.


The analyzer in neutron protein crystallography.

The use of a pyrolytic graphite analyzer is shown to contribute to the cleanliness of a neutron protein crystallographic study. If neutrons of approximately 1.5-A wavelength are used, higher orders are reduced by nearly an order of magnitude, and background (arising largely from incoherent inelastic neutron-proton scattering) is reduced by nearly a factor of five. These advantages are gained at the expense of approximately 50% of measured integrated intensity and a distortion of integrated intensity with scattering angle. Because background scatter is generally large compared with peak reflectivity of a protein, the large background reduction by the analyzer more than compensates for reduced peak intensity to improve the statistics of most peak reflectivity measurements. The luminance function distortion of intensity data is not large, produces a slight smearing of atomic scattering density, and can be calculated and adjusted for in the data.


Inelastic scattering of neutrons and possible biological applications.

The field of neutron inelastic scattering has probably been developed to the stage where it can begin to help the biologist. Because essentially no experimental data have been obtained, it is difficult either to draw conclusions or to make forecasts except on the basis of general hypotheses. It seems likely, however, that the next stage is up to biologists. After reviewing those biological problems in which molecular dynamics might play an important role, they should suggest specimens of interest which can give inelastic peaks with existing spectrometers operating with 5 to 10-A neutrons at angles greater than 5degrees and with resolutions of approximately 50 mueV. These specimens may involve molecules slightly smaller and more mobile than some biologists would like, but a successful outcome might lead to the development of spectrometers capable of working in a more satisfactory range. In this event the return may well prove rewarding to the biologists.


Baculovirus-like particles in the reproductive tracts of female parasitoid wasps.

Virus-like particles have been found in specific regions of the reproductive tracts of three different braconid wasps, all parasitoids of the tobacco budworm, Heliothis virescens. The particles are nuclear in origin, and Feulgen cytochemistry of particulate fluid in the calyx and oviducts of one species has revealed the presence of DNA. On the basis of apparent structural homologies, it is suggested that the parasitoid particles are related to baculoviruses.


Effect of volatile inhibitors from natural and amended soils on germination of sclerotia of Macrophomina phaseolina.

Studies on volatile soil fungistasis showed that sclerotia of Macrophomina phaseolina are not sensitive to volatiles liberated by natural soils with varying pH values. Soil amended with alfalfa hay (1%, w/w) liberated volatiles fungistatic to sclerotia only when the assay was performed 2 weeks or less after amendment. Chitin-amended soils liberated fungistatic volatiles from 1 to 3 weeks after amendment. Indirect evidence indicated that ammonia may be the active volatile in amended soil. It was concluded that fungistatic volatiles may not play an important role in the survival of sclerotia in nature.


Bacteriocins of Streptococcus bovis.

Forty-seven strains of Streptococcus bovis were tested for bacteriocin production. Fourteen were found to produce bacteriocins, while all 47 were sensitive to at least one of these bacteriocins. The bacteriocins, on the basis of their host range on S. bovis strains, formed six groups. A representative of each group was selected and characterized by temperature stability, sensitivity to trypsin and lipase, sedimentation by centrifugation, ability to pass through dialysis tubing, host range on other bacterial species, and conditions for production in liquid media. A correlation between mannitol fermentation and bacteriocin production was noted.


Site of action of nonheme iron in the malate (flavine adenine dinucleotide) pathway of Mycobacterium phlei.

Irradiation with ultraviolet light (360 nm) of cell-free extracts, electron-transport particles, and soluble components from Mycobacterium phlei resulted in the loss of malate oxidation by the flavine adenine dinucleotide pathway both in cell-free extracts and reconstituted systems. Addition of vitamin K1 restored the loss to the extent of 14% and 11% in cell-free extracts and reconstituted systems respectively. Electron-transport particles from M. phlei upon reduction with malate exhibited electron-paramagnetic resonance signals at g = 2.002 and 1.94, characteristic of napthosemiquinone and nonheme iron protein, respectively. Upon irradiating the particles with ultraviolet light (360 nm) these signals were not observed. Particulate flavine-adenine-dinucleotide-dependent malate dehydrogenase (EC 1.1.1.37) of M. phlei assayed by the 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyl tetrazolium bromide and phenazine methosulfate - 2,6-dichlorophenolindophenol systems, which trap electrons at cytochrome c and at the flavine level respectively, was inhibited by o-phenanthroline. These observations suggest that nonheme iron protein is sensitive to ultraviolet light (360 nm) and participates before or in combination with flavine in the malate (flavine adenine dinucleotide) pathway of M. phlei.


Differences in physicochemical and antigenic properties of chlamydial strains.

Antigenic analysis of Chlamydia psittaci, C. trachomatis, and Lymphogranuloma venereum (LGV) revealed basic physicochemical differences among the three chlamydial strains. These were manifested in structural, isoelectric points, absorption spectra, and in the characteristics of the chromophobe-containing proteins. The effective period of sonication for C. psittaci and C. trachomatis is around 60 min during which the linkages most susceptible to external sonication forces were broken, releasing all attainable cellular components. Denaturation studies demonstrated that less than 50% of protein content of C. psittaci was denatured after 1 h of sonication, only 5% in the case of C. trachomatis. The protein and carbohydrate content of the most reactive fractions in macrophage-spreading inhibition test were different for LGV and C. trachomatis. The structural differences appear to determine the antigenic properties observed among the chlamydial strains as well as the specificity and probably the mechanisms (s) of cellular immune reactivity to Chlamydiae. This in turn may explain the failure of chlamydial vaccines, prepared from stock strains, to protect immunized children against 'wild' chlamydial strains.


Colonial variation in Xanthomonas campestris NRRL B-1459 and characterization of the polysaccharide from a variant strain.

Stock cultures of Xanthomonas campestris NRRL B-1459 require special attention to maintenance and propagation to assure consistent production in good yields of the extracellular polysaccharide xanthan. Under customary conditions of propagative maintenance on agar slants, variant colony types develop that are smaller in size than the normal type. The rate of regression of the normal to the variant forms was diminished when the D-glucose content of the stock medium was sufficient to avoid depletion during storage and when transfer to fresh medium was reduced to 14-day intervals. Under conditions for polysaccharide production, the normal large-colony type gives crude culture liquors after 48 h of 7000 centipoise (cp) viscosity; the predominant variant form gives only 4000 cp. On the basis of 2.1% initial D-glucose, biopolymer yields for the normal and variant strains were 62 and 43%, respectively. Polysaccharide produced by the variant (small-colony type) differs adversely in solution properties from that of the parent strain (large-colony type); it differs also in its lower content of pyruvic acid and O-acetyl substituents. The molar ratios of constituent sugars (D-glucose, D-mannose, and D-glucuronic acid), however, were identical in polysaccharides with the normal and variant strains. Exclusion of colonial variants from fermentations is prerequisite to production of xanthan optimum in properties and yield.


Reduction of acetylene by stationary cultures of free-living Rhizobium sp. under atmospheric oxygen levels.

The reduction of acetylene to ethylene by stationary (non-shaking) cultures of free-living rhizobia under atmospheric oxygen levels has been demonstrated. Under these conditions the development of the activity is inhibited by 10 mM NH4Cl and about 20% of oxygen is required for maximal activity. When the stationary cultures were shaken, oxygen concentrations of 1% and higher were found to be inhibitory. Specific activities of 20 and 40 nmol of acetylene reduced h-1 mg-1 protein were observed.


In field survival of Rhizoctonia solani in soil and in diseased sugarbeets.

Persistence of Rhizotonia solani in the field was investigated by ascertaining survival (competitive saprophytic activity) in soil and survival in diseased plants. Except for one instance, low levels of R. solani survived overwinter in artificially and naturally infested soils. In a sandy loam soil, cropped to sugarbeets, inoculum density increased throughout the growing season from low early spring levels to high levels in July and August. In a silty clay soil, cropped to sugarbeets, inoculum density remained low with only a slight increase throughout the growing season. Survival of R. solani in diseased sugarbeets placed on the soil surface was greater than survival in diseased beets buried in soil. Little reduction in percentages of beets yeilding R. SOLANI COLONIES TOOK PLACE FROM November to April in either buried or unburied beets. The major reduction in survival of R. solani in buried beets occurred during the 6-week interval from April to June.


A modified procedure for studying enzyme secretion in yeast sphaeroplasts: subcellular distribution of invertase.

A significantly modified procedure for investigating enzyme secretion from yeast sphaeroplasts, and results from its application are described. Sphaeroplasts were derepressed for invertase biosynthesis in the presence of helicase and fractionated to reveal the distribution of high and low molecular weight forms of invertase. Secreted enzyme was found to be of high molecular weight, exclusively. Less than 10% of the total invertase activity was present in washed sphaeroplasts and of this, 43% was soluble, consisting of both high and low molecular weight forms of invertase. Washed membranes retained 32% of the internal invertase activity, and on solubilization with Triton X-100 the enzyme was found to be of an intermediate molecular weight. These results are consistent with the hypothesis that invertase is glycosylated at the plasma membrane.


[Metabolic activity of Candida lipolytica adsorbed to bentonite with hydrophobic chains].

The respiration of Candida lipolytica on n-tetradecane is decreased in the presence of bentonite. This inhibition is less pronounced by the introduction of hydrophobic chains on the bentonite. Oxygen demand of resting cells varies with the length of hydrophobic chains. In fermentor, addition of adsorbant does not stimulate growth, but assimilation of n-tetradecane is enhanced with certain concentrations of the adsorbant. On glucose, addition of hydrophobic chains on the adsorbant does not change the effects of bentonite on exogenous respiration and substrate assimilation.


Characterization of group A streptococcal M-proteins purified by two methods.

Ten different group A streptococcal M-protein preparations purified by trichloroacetic acid precipitation and three M-protein preparations purified by cellulose chromatography were examined by SDS and polyacrylamide gel electrophoresis, and analyzed for amino acid composition and N-terminal amino acids. Fingerprinting (both tryptic and chymotryptic) was performed on the cellulose purified preparations of M1, M12, and M29 proteins which showed these proteins to be structurally related. Trypsin produced mas with 37 to 42 peptides, whereas chymotrypsin digestion resulted in 8 to 12 peptides,  depending on the M-type. Sequencing was performed on the M12 protein and tentative identification of nine N-terminal amino acids made. Molecular weights of the cellulose and TCA-purified M-proteins were determined by SDS gel electrophoresis and chromatography on G-200 Sephadex, with comparable results, indicating followed the patterns established for M-proteins, with high concentrations of lysine, aspartic acid, glutamic acid, alanine, and leucine. All 10 proteins had L-alanine as their N-terminal amino acid. Evidence for a one way cross-reaction between type 1 and type 29 streptococci was also found.


The citric acid fermentation by Aspergillus niger: regulation by zinc of growth and acidogenesis.

The citric acid fermentation by Aspergillus niger is divided into two consecutive phases, a growth phase when the cells proliferate but do not accumulate citrate, followed by an accumulating phase when they produce citrate but do not proliferate, or else do so at a much reduced rate. When studied in a low sucrose (0.4-0.8%) mpinimal salts medium the growth-accumulation alternative was controlled by the concentration of zinc: high zinc (about 1-2 muM) maintained growth phase, while at low zinc (below 1 muM) growth became limited by zinc deficiency and the cultures passed into accumulating phase. Addition of zinc to accumulating cultures resulted in their reversion to growth phase. Iron, manganese, calcium at concentrations as high as 5-10 muM had no influence on either growth or citrate accumulation. These results suggest that zinc plays a role in the regulation of growth and citric acid accumulation.


The fine structure of conidial development in the genus Torula. IV. T. thermophila Cooney & Emerson.

Torula thermophila produced typical chlamydospores either as intercalary chains within prostrate hyphae or as terminal swellings on short, lateral, hyphal branches. Mature chlamydo-spores were spherical, dark brown, smooth-surfaced structured structures with thick, single-layed cell walls (= secondary wall layer) usually differentiated into an outer electron-dense zone and an inner electron-transparent zone. Disarticulation and sport release occurred after the disintegration of the original hyphal wall. The thallospores of T. thermophila arise in a manner different from the blastospores produced by other species of Torula and are structurally more closely related to the spores produced by Humicola insolens. However until further work has been completed on spore development in the Torula-Humicola complex of fungi the name T. thermophila is retained.


Antibody production in milk serum of goats experimentally infected with Neisseria gonorrhoeae.

Instillation of the goat's mammary gland with Neisseria gonorrhoeae colony type T1 has elicited and antibody response in the goat milk serum (GMS). Purification, and characterization of the GMS by gel filtration, electrophoresis, immunodiffusion, analytical ultracentrifugation, and serological analyses demonstrated thtat the active immune component was mainly in the IgA and IgG fractions (F2 and F3) of GMS.


California encephalitis virus proliferation in Yukon mosquitoes incubated at low temperatures.

Replication of a subarctic Bunyavirus, California encephalitis (snowshoe hare subtype), was detected in salivary glands and thoraces of wild-caught Aedes communis mosquitoes from the Yokon Territory, after intrathoracic inoculation with 0.1 to 100 mouse LD50 virus, and incubation for 7 to 21 days throughout their viable temperature range of 0 to 23 degrees C. Immunoperoxidase staining confirmed that viral replication occurred in the cytoplasm of acinar cells of salivary glands, both by ligh microscopy and electron microscopy. Replication of another subarctic Bunyavirus, Northway, and a subtropical Flavivirus, Murray Valley encephalitis, was also demonstrated by infectivity by infectivity titrations and immun operoxidase reactions in salivary glands of A. communis incubated at 0, 13, and 23 degrees C for 7 to 21 days.


Toxicity and plant growth regulator effects of cytochalasin H isolated from Phomopsis sp.

A biologically active metabolite was found in crude extracts of an unidentified species of Phomopsis isolated from weevil-damaged pecans. Purified metabolite was toxic to day-old cockerels, with an LD50 of 12.5 mg/kg, and was markedly inhibitory to growth the floral development of tobacco plants at concentrations of 10(-2) to 10(-4) M. IR and 1H-nmr spectra indicated an alkylpheny moiety with a single nitrogen atom present as a secondary amide; and acetate ester, OH, CH3, and a trans-double bond function. Elemental and high-resolution mass-spectral analysis indicated a formula of C30H39NO5 and a molecular weight of 493.2886. The metabolite was identified as cytochalasin H.


A cellulase complex in culture filtrates of Penicillium citrinum.

During growth in a liquid medium that contained a single soluble or an insoluble cellulosic carbon source Penicillium citrinum released a complex of cellulase enzymes into the medium. A temperature of 30 degrees C was best for cellulase production. Presence of carbon-containing compounds, particularly glucose, inhibited cellulase activity. The enzyme complex was separated by gel filtration followed by ion-exchange chromatography into 11 components, 4 of high molecular weight and 7 of low molecular weight. One of the components (Bb) had the character of C1 cellulase enzyme. When the components were combined they released more reducing sugars from cullulosic substrates than when they were used singly.


In vitro binding of sterols by extracts from Mucor rouxii cells grown under different environmental conditions.

Aqueous cell wall and cytoplasm extracts from Mucor rouxii cells grown under acrobic and anaerobic (oxygen-limiting) conditions were obtained. Both of the extracts from the anaerobic and aerobic cells solubilized lanosterol and ergosterol but not to the same extent; ergosterol was complexed about 2-3 times greater than the same concentration of lanosterol. It was also apparent that the relative bindingcapacities of the cell extracts were dependent on the cell growth environment. Two additional fractions were obtained from each extract by (a) methanol precipitation and (b) refluxing in 2% aqueous potassium hydroxide solution followed by methanol precipitation. The binding activities of these precipitates and the corresponding precipitates from yeast extract were compared and the results indicated a range of binding activites which depended on both the extract and the sterol. The data suggested that the in vitro sterol binding of M. rouxii extracts was not due to one particular macromolecule but that a number of compounds were involved in this complexation process.


Photoreactivating property of the Vibrio cholerae cell system.

Ultraviolet-inactivated chlora phage PL163/10 underwent a maximum of abot 36% of photoreactivation within the host V. cholerae cells. UV-inactivated but non-infected V. cholerae cells also underwent the same degree of photoreactivation.


The metabolism of carbohydrates by extremely halophilic bacteria: identification of galactonic acid as a product of galactose metabolism.

Cell-free extracts prepared from the extremely halophilic bacterium Halobacterium saccharovorum oxidize galactose and accumulate a product which reacts as if it were a lactone. The product does not act as a reducing sugar and contains all six of the carbon atoms initially present in galactose. The product was jugged to be galactonic acid, based on the behavior of the acetylmethyl ester derivative of the product and the pentaacetyl derivative of the galactonic methyl ester during gas chromatography.


Magnesium requirement of Staphylococcus aureus for repair from sublethal heat injury.

Heating in potassium phosphate buffer causes Staphylococcus aureus to lose its salt tolerance and 30-40% of its cellular Mg2+. Repair from injury (regain of salt tolerance) occurred when injured cells were incubated under optimal conditions in synthetic media containing penicillin to prevent growth. Cells died when phosphates or amin acids were omitted from the medium. Omission of vitamins, glucose, Na+, and K+ had no effect. Omission of Mg2+ diminished repair. In a minimal repair medium (MRM) which contained only 3 X 10(-6) M Mg (as an impurity), injured cells rapidly regained their original Mg content. About 20-50% of the cells also regained their salt tolerance provided that less than 10(9) cells/ml were used. With 10(10) cells/ml there was no repair and cellular Mg content was half that of the control. Addition of 10(-3) M ethylenediamine-tetraacetic acid (EDTA) to MRM also prevented repair. Addition of 10(-2) M Mg to MRM EDTA permitted complete repair.


The relationship between chemical structure of attractants and chemotaxis by a marine bacterium.

The chemotactic responses of a marine pseudomonad to steroisomers and analogues of amino acids and sugars were tested. The data reveal that the bacterium is equally attracted to D, L, and DL forms of the amino acids. In contrastr, chemical analogues of the amino acids and glucose yielded significantly lower chemotactic responses. The threshold of bacterial detection was 10(-8) M for leucine and cysteine. However, the threshold molarity of most of the analogues was higher than those of the related amino acids and sugars.


Biodegradation rates of components of petroleum.

Rates of microbial biodegradation of components of South Louisiana crude oil were determined by computer analysis of data obtained from computerized mass spectrometry. Total residue of the oil decreased exponentially with time, with maximum decrease noted at logarithmic phase, whereas asphaltenes and resins increased at the logarithmic phase of growth. Saturates decreased continuously during growth. Microbial degradation of components of crude oil was concluded to be a dynamic process.


An unusual occurrence of multiple sclerosis in a small rural community.

Ten patients with multiple sclerosis were found to have lived in close proximity in a Nova Scotia farming community of 150 people. All had drunk unpasteurized milk as children, were teetotallers, ate a high animal fat diet, and were well educated. Of greater interest was the observation that six of the ten cases were related in two family groups. The only time all patients lived in the community at the same time was in 1951 and 1952 during a polio outbreak. The relationship of polio to multiple sclerosis bears further study. The average age of the patients when they had measles was 11.8 years. Evidence suggests a link between risk of multiple sclerosis and both late onset of measles and pubertal age. Late onset of measles may be important in this cluster. Further epidemiological studies are needed to examine the age of onset of measles in M.S. cases.


Shy-Drager syndrome. Neuropathological correlation and response to levodopa therapy.

The post-mortem examination of the nervous system of a patient with Shy-Drager syndrome successfully treated with levodopa (Sharpe et al, 1972) revealed features of striato-nigral degeneration and amyotrophic lateral sclerosis, a cerebellar system degeneration and a loss of approximately 75% of sympathetic preganglionic neurons. Lewy bodies were not present and no detectable changes were observed in the sympathetic prevertebral ganglia. While the limited and transient beneficial effect of levodopa on the bradykinesia in our case is possibly due to the progressive loss of striatal dopaminergic receptors seen in striatonigral degeneration, we propose that in Shy-Drager syndrome, levodopa therapy benefits orthostatic hypotension because of a suppression of the central depressor action of this drug. This suppression is attributable to functional disconnection of sympathetic ganglia secondary to the loss of preganglionic neurons or to degeneration of central autonomic catecholaminergic systems.


Intellectual performance in multi-infarct dementia and Alzheimer's disease a replication study.

A consistent feature in dementia is an overall intellectual deterioration. The present study investigated the intellectual performance of patients with Alzeheimer's disease (AD) and multi-infarct dementia (MID) using the Wechsler Adult Intelligence Scale (WAIS). For reliability and generality purposes two independent samples of patients were collected. Significant differences in Education Level (EDU) and Performance IQ (PIQ) were obtained for the first sample, with the AD group having a significantly higher EDU level. The MID group obtained a higher PIQ. No significant differences were found in the second sample, but EDU level approached significance with the AD group again having a higher EDU level. A discriminant function analysis classified 81% of the patients in the first sample and 100% diagnostic accuracy was obtained for the second sample using the 11 predictor variables. A maximum R2 stepwise regression was performed in order to detect the "best" model of variables discriminating between the diagnostic groups. For the first sample the "best" model was the two variable model, including EDU and Full Scale IQ, accounting for 40% of the variance. The simplest model for the second sample was the one variable model including EDU, accounting for 20% of the variance. Quantitative differences were found between the AD samples. Time since onset of the disease was offered as a possible influence in the quantitative differences in the AD samples. Sampling biases in the behavioral study of dementia are discussed. Successful replication was obtained.


Intracranial dysgerminomas.

We have reported three cases of intracranial dysgerminoma. The origin of these tumors has been controversial for a long time. It is now accepted that they develop from germ cells. The diagnosis is often difficult to confirm because of the varity of signs. If their origin is now accepted, the best way to deal with these lesions is still controversial. They can be macroscopically removed if they are in the pineal region. Such treatment is not possible for suprasellar tumors. Since these tumors can metastasize, radiation should be administered as soon as a pathological diagnosis is obtained. It is our belief that it should be administered to the whole spinal axis.


Congenital intraspinal extradural cysts (intraspinal meningocele).

A case of congenital, intraspinal, extradural cyst is reported with pain as the only presenting feature. In the past, the lack of pain has been considered one of the characteristics of these rare lesions. In other reported cases, when pain has been present, it was minimal and never the presenting feature. The clinical and radiographic features and the surgical treatment are described. The pathogenesis is discussed and the literature reviewed. An addition to the surgical technique is given whereby one of the post operative complications may be obviated.


Computer tomography in disseminated sclerosis.

A case is reported where the appearance of acute, diffuse, disseminated sclerosis on computer tomography (Ct scan) is described and the literature is reviewed. This disease may give rise to multiple, small areas of diminished X-ray absorption which may decrease in size during the course of the disease. The histological features of one of the lesions was correlated with the radiological findings. It is suggested that, perhaps, only during the active stage of demyelination can the lesions be detected on the Ct scan.


Focus on prevention.

Cardiovascular disease in Canada is estimated to cost over $1.2 billion each year. Advances made in the treatment of cardiovascular diseases have decreased the mortality rate associated with them, but the incidence of such diseases may nonetheless be termed epidemic. Leading epidemiologists suggest that control of this epidemic can only be attained through primary prevention....


A synthesis of 3',4'-dideoxykanamycin B.

3',4',-Dideoxykanamycin B, the kanamycin B derivative that is active against resistant bacteria, was prepared from kanamycin B via N-tosylation, 3',4'-O-sulphonylation, 3',4'-unsaturation, and hydrogenation. The unsaturated intermediate was obtained from the 3',4'-di-O-sulphonyl derivatives by the action of sodium iodide in N,N-dimethylformamide; if zinc dust was added in this reaction, aziridine derivatives were formed. Removal of the tosyl group was successfully performed by using sodium in ammonia-ethylamine.


Synthesis of the allo-analogue of trehalose.

Selective benzoylation of HO-2 and HO-2' of 4,6-O-benzylidene-alpha-D-glucopyranosyl 4,6-O-benzylidene-alpha-D-glucopyranoside with N-benzoylimidazole led to the exclusive formation of 2-O-benzoyl-4,6-O-benzylidene-alpha-D-glucopyranosyl 2-O-benzoyl-4,6-O-benzylidene-alpha-D-glucopyranoside. Oxidation of either the dibenzoate or the corresponding ditosylate with methyl sulphoxide--phosphorus pentaoxide gave the 3,3'-diulose, and subsequent reduction with borohydride gave the 3,3'diepimers having the allo-allo configuration. De-esterification and hydrolysis of the benzylidene substituents gave alpha-D-allopyranosyl alpha-D-allopyranoside.


Synthesis of L-fucose 2-, 3-, and 4-sulphates.

Treatment of L-fucose with an excess pf pyridine-sulphur trioxide gave an equilibrium mixture of mono-, di-, and tri-sulphates. L-Fucose was sulphated under optimal conditions for monosulphate formation, and the monoester fraction was isolated by chromatography on DEAE-cellulose. The isomeric L-fucose 2-, 3-, and 4-sulphates (1-3) were separated on a DEAE-cellulose column by elution with borate buffer. The structures of 1-3 were established by electrophoresis, colour tests, periodate oxidation, and, for the 2-isomer, by comparison with a specimen of 1 that had been definitively synthesised via methyl 3,4-O-isopropylidene-alpha-L-fucopyranoside (6) and methyl alpha-L-fucopyranoside 2-(barium sulphate) (5). The latter was rapidly hydrolysed in hot, dilute acetic acid to 1 and methyl alpha-L-fucopyranoside (4).


An approach to the synthesis of branched-chain amino sugars from C-methylene sugars.

The reaction of 1,2:5,6-di-O-isopropylidene-3-C-methylene-alpha-D-ribo-hexofuranose (4) with mercuric azide in hot 50% aqueous tetrahydrofuran yielded, after reductive demercuration, 3-azido-3-deoxy-1,2:5,6-di-O-isopropylidene-3-C-methyl-alpha-D-glucofuranose (5). Partial, acid hydrolysis of 5 afforded the diol 7, which gave 3-azido-3-deoxy-1,2-O-isopropylidene-5,6-di-O-methanesulphonyl-3-C-methyl-alpha-D-glucofuranose (8) on sulphonylation. On hydrogenation over a platinum catalyst and N-acetylation, the dimethanesulphonate 8 furnished 3,6-acetyleprimino-3,6-dideoxy-1,2-O-isopropylidene-5-O-methanesulphonyl-3-C-methyl-alpha-D-glucofuranose (9), which was also prepared by an analogous sequence of reactions on 3-azido-3-deoxy-1,2-O-isopropylidene-5-O-methanesulphonyl-3-C-methyl-6-O-toluene-p-sulphonyl-alpha-D-glucofuranose (13). The formation of the N-acetylepimine 9 establishes the D-gluco configuration for 5. 1,2-O-Isopropylidene-3-C-methylene-alpha-D-ribo-hexofuranose (20) reacted with mercuric azide in aqueous tetrahydrofuran at approximately 85 degrees to give 3,6-anhydro-1,2-O-isopropylidene-3-C-methyl-alpha-D-glucofuranose (22) as a result of intramolecular participation by the C-6 hydroxyl group in the initial intermediate.


G.L.C. of the O-trimethylsilyl derivatives of hexuronic acids.

The free acids, sodium salts, and lactones of several hexuronic acids have been studied as their O-trimethylsilyl derivatives by gas-liquid chromatography using SE-30 and XE-60 liquid phases. Silylation was best performed in methyl sulphoxide. The equilibrium between the various forms of a hexuronic acid in methyl sulphoxide was also studied by g.l.c. following silylation. The hexamethyldisilazane used in the silylation disturbed the equilibrium attained in the solvent, but this was overcome by premixing the hexamethyldisilazane with chlorotrimethylsilane. Methyl sulphoxide and the silylating reagents gave a two-phase system in which the derivative was favourably partitioned into the upper layer. Partition coefficients and stabilities of the derivatives were measured, and a g.l.c. method for the analysis of the hexuronic acids was thereby developed. The oximes of the hexuronic acids were studied as alternative derivatives for g.l.c., and their equilibrium compositions and g.l.c. retention times are recorded.


Reaction of derivatives of methyl 2,3-O-benzylidene-6-deoxy-alpha-L-mannopyranoside with butyllithium: synthesis of methyl 2,6-dideoxy-4-O-methyl-alpha-L-erythro-hexopyranosid-3-ulose.

Methyl 2,3-O-benzylidene-6-deoxy-alpha-L-mannopyranoside (2) reacted with butyllithium to give a mixture of 1,5-anhydro-3-C-butyl-1,2,6-trideoxy-L-ribo-hex-1-enitol (3) and its L-arabino analogue (4), together with methyl 2,3,6-trideoxy-alpha-L-erythro-hex-2-enopyranoside (5). In contrast, the 4-O-methyl-analogue (8) of 2 was converted by butyllithium into methyl 2,6-dideoxy-4-O-methyl-alpha-L-erythro-hexo-pyranosid-3-ulose (9), which was further characterized as its oxime 10. The 4-O-benzyl analogue of 8, obtained as two separate diastereoisomers (6 and 7) differing in configuration at C-2 of the dioxolane ring gave a complex misture of products on treatment with butyllithium.


Synthesis of benzyl and allyl ethers of D-glucopyranose.

Starting from allyl 3-O-benzyl-4,6-O-benzylidene-alpha-D-glucopyranoside as a key intermediate, the following crystalline compounds were prepared: 2-O-allyl-3,4,6-tri-O-benzyl-D-glucopyranose (11) and its p-nitrobenzoate; 2,3,5-tri-O-benzyl-D-arabinofuranose (12) and the corresponding arabinitol; allyl 3,4,6-tri-O-benzyl-alpha-D-glucopyranoside (7); 3,4,6-tri-o-benzyl-D-glucopyranose (8); 2-0-allyl 3, 4-di-o-benzyl-D-glucopyranose (17) and its bis(p-nitrobenzoate); and 3,4-di-O-benzyl-D-glucopyranose (19). The p-nitrobenzoates of compounds 11 and 17 are potential intermediates for the synthesis of the glycolipids of the cytoplasmic membranes of Streptococci.


Structure of the levan elaborated by Streptococcus salivarius strain 51: an application of chemical-ionisation mass-spectrometry.

The polysaccharide elaborated by Streptococcus salivarius strain 51 contains beta-D-fructofuranose residues linked through positions 2 and 6, as well as 1, 2, and 6. The approximate numbers of terminal, non-reducing D-fructofuranose residues and those linked through positions 2 and 6, and through 1, 2, and 6 in the average repeating-unit are 1, 7, and 1, respectively. The branches through the beta-(2 leads to 1)-linkage contain up to at least four D-fructofuranose residues. Chemical-ionisation mass-spectrometry aids the assignment of structures to O-acetyl-O-methylalditols obtained in methylation analysis.


A 13C-N.M.R. spectral study of chondroitin sulfates A, B, and C: evidence of heterogeneity.

Chondroitin sulfates A, B, and C produce well-resolved 13C-n.m.r. spectra which allow for a more complete characterization than that available from their p.m.r. spectra. The 13C data fully support earlier evidence as to the main structural features of these glycosaminoglycans, but they also show that many chondroitin preparations are substantially heterogeneous in composition. Thus, spectra of chondroitin A and C have the appearance of composites representative of both types of polymer: specimens of A may contain 25% of the C-type of structural sequence, and C,30% of the A-type of sequence; 10-20% of unidentified constituents, including a residue bearing a 6-sulfate group, are present in the specimens of chondroitin B. Chemical-shift and 1JC-H values found for the L-iduronic acid residues of chondroitin B, as well as the effect of gadolinium nitrate on the relaxation properties of its 13C nuclei, indicate that this moiety possesses the alpha configuration and favors the 1C4(L) conformation. Corresponding data for the acetamidodeoxy-D-galactose and D-glucuronic acid residues of the chondroitins are consistent with the beta-anomeric configuration and 4C1(D) conformation in all instances.


Some properties of a fungal beta-D-glucanase preparation.

A commercial enzyme preparation, of fungal origin, contained a mixture of beta-D-glucanases which were fractionated by ion-exchange chromatography to give a mixture of an endo-(1 leads to 4)- and an exo-(1 leads to 3)-beta-D-glucanase. These two enzymes were then separated by molecular-sieve chromatography on Sephadex G-150. The purified exo-(1 leads to 3)-beta-D-glucanase has a relatively high specificity for (1 leads to 3)-beta-D-glucosidic linkages, and has no action on lichenin.


Preparation and characterization of a dextran-amylase conjugate.

Bacillus amyloliquefaciens alpha-amylase was attached to dextran after activation of the polysaccharide by using a modification of the cyanogen bromide method. The soluble dextran-amylase conjugate was purified by molecular-sieve chromatography. The conjugated enzyme has greater stability than the unmodified enzyme at low pH values, during heat treatment, and on removal of calcium ions with a chelating agent. Attachment of dextran to alpha-amylase did not alter the Michaelis constant of the enzyme acting on starch. The polysaccharide-enzyme conjugate probably consists of a cross-linked aggregate of many dextran and many enzyme molecules, in which a proportion of the enzyme molecules, although not inactivated, are unable to express their activity, except after dextranase treatment.


The agar-type polysaccharide from the red alga Ceramium rubrum.

Aqueous extraction of the red alga C. rubrum gave a galactan sulphate and, possibly, a separate glucan and xylan. The galactan sulphate has an alternating structure of the agar-type with D-galactose or 6-O-methyl-D-galactose as one alternating unit, and L-galactose, 3,6-anhydro-L-galactose, and their respective 2-methyl ethers as the other unit. Sulphate hemi-ester groups are present on position 6 of both D- and L-galactose residues, with smaller amounts on positions 2 and 4 of, probably, D-galactose residues. The polysaccharide differs from others previously examined in that most of the L-galactose residues are non-sulphated.


Structural investigations of the extracellular polysaccharide elaborated by S19, a Xanthomonas-type bacterium.

The extracellular, acidic heteropolysaccharide from Xanthomonas S19 consists of D-glucuronic acid, D-glucose, D-galactose, and D-mannose residues in the approximate molar ratios of 1.6:3:1:1, plus acetyl groups linked to C-2 and/or C-3 of a large proportion of the glucose residues. Methylation studies showed that the glucose is present as non-reducing end-group also as 1,2- and 1,4-linked units, the galactose residues are solely 1,3-linked, a major proportion of the mannose residues are 1,2,4-linked and the rest 1,2-linked. A high proportion of the glucuronic acid units are 1,4-linked. Periodate oxidation confirmed the presence of these linkages. The disaccharides D-Glc-(1 leads to 4)-D-Glc, D-Glc-(1 leads to 2)-D-Man, D-Glc-(1 leads to 3)-D-Gal, D-Gal(1 leads to 2)-D-Glc, D-GlcA-(1 leads to 4)-D-GlcA, and beta-D-GlcA-(1 leads to 4)-D-Man were isolated from a partial hydrolysate of the polysaccharide, and characterised. The similarities and differences between this polysaccharide and those from other Xanthomonas species are discussed.


[Complete structure of three galactoxyloglucans (amyloids) from seeds].

D-Galacto-D-xylo-D-glucans (amyloids) from Balsamina, Tropaeolum, and Tamarindus seeds behave in a similar manner in the presence of various glycosidase preparations: slow depolymerization by enzymes from several germinated or non-germinated seeds, and hydrolysis into monosaccharides and oligosaccharides by commercial cellulase and hemicellulase preparations from fungi. A purified cellulase from Penicillium notatum gave a dialyzable fraction almost exclusively composed of alpha-D-xylopyranosyl-(1 leads to 6)-D-glucose residues and a nondialyzable fraction composed of chains of beta-D-(1 leads to 4) [With some (1 leads to 3)]-glucopyranosyl residues; beta-D-galactopyranosyl-(1 leads to 2)-alpha-D-xylosyl groups are linked to some of the beta-D-glucosyl residues at O-6. The presence of (1 leads to 3)-linkages in the D-glucan chain of the Balsamina was verified by methylation and sequential periodate oxidation-borohydride reduction; the distribution of the substituents on the D-glucan chain is not regular. The main D-glucan backbone, where the  beta-D-glucosyl residues are partly linked at O-6 to beta-D-galactosyl-(1 leads to 2)-D-xylosyl groups, is linked to D-glucan chains where almost all the D-glucose units are linked at O-6 by one alpha-D-xylosyl group. The presence of 3,6-di-O-methyl-D-glucose after permethylation and hydrolysis suggests that the xyloglucan chains are linked to O-2 of the D-glucosyl units of the galactoxyloglucan backbone.


Neighbouring acetamido-group participation in reactions of derivatives of 2-acetamido-2-deoxy-D-glucose.

Kinetic measurements suggest that neighbouring acetamido-group participation occurs in the spontaneous hydrolysis and methanolysis of o-carboxyphenyl 2-acetamido-2-deoxy-beta-D-glucopyranoside and in the spontaneous hydrolysis of 2,4-dinitrophenyl 2-acetamido-2-deoxy-beta-D-glucopyranoside and 2-acetamido-2-deoxy-beta-D-glycopyranosyl fluoride. The methanolyses of these compounds proceed with predominant retention of configuration which is also consistent with neighbouring acetamido-group participation. The oxazoline intermediate which would arise from such a process was detected during methanolysis of 2-acetamido-2-deoxy-beta-D-glucopyranosyl fluoride in the presence of bases by n.m.r., i.r., and u.v. spectroscopy. Attempts to isolate the oxazoline were unsuccessful.


The ventral lateral geniculate nucleus, pars lateralis of the rat. Synaptic organization and conditions for axonal sprouting.

The synaptic organization of the pars lateralis portion of the ventral lateral geniculate nucleus is similar to that of other thalamic nuclei. There are four types of synaptic knobs (RL, RS, F1, F2). RL knobs are large and irregularly shaped, contain round synaptic vesicles and make multiple asymmetrical junctions. They are found primarily in "synaptic islands" making contact with gemmules, spines, small dendrites, and other synaptic profiles containing pleiomorphic synaptic vesicles (F2). Smaller RS knobs contain round vesicles and make asymmetrical junctions with the same type of elements as RL knobs, with the exception of the F2 profiles, but are seldom found in synaptic islands. F1 knobs contain flattened synaptic vesicles and form symmetrical junctions with F2 knobs, gemmules, spines, and small-medium dendrites in synaptic islands, throughout the neuropil, and on the proximal dendrites and soma of the largest type of neuron. F2 knobs are irregularly shaped, contain pleiomorphic synaptic vesicles and make symmetrical junctions primarily with gemmules and spines in synaptic islands. They are postsynaptic to RL and F1 knobs. Occipital decortication indicates that cortical terminals are of the RS type. Bilateral enucleation indicates that retinal terminals are of both the FL and RS type. The large amount of geographic overlap of retinal and cortical terminals on gemmules, spines, and small dendrites found in the neuropil outside of synaptic islands logically would maximize axonal sprouting between these two sources.


Spermatogenesis of a marine snail, Littorina sitkana.

The fine structure of the spermatogonium, spermatocyte and spermatid of a marine snail, Littorina sitkana is described. The ring centriole (annulus) is formed from the distal centriole and it migrates to the base of the mitochondrial region where it lies in a joint-like structure which is formed by an area of invaginated plasma membrane. The distal and proximal centrioles are at first perpendicular to each other but the proximal centriole rotates to a position coaxial with the distal centriole and fuses with it. The peripheral doublet fibers are continuous between the two centrioles but the central fibers originate only in the distal centriole. The acrosome differentiates from the proacrosomal granule which is derived from a Golgi body. Microtubules, present at this stage, may assist acrosomal formation. Chromatin condensation begins with the formation of fibrous strands, then to lamellar plates which become folded and later twisted around the flagellar shaft. In the final stages the lamellae appear in cross section as concentric rings which eventually fuse to form a homogeneously dense nuclear tube.


Inhibition of 5'-nucleotidase by concanavalin A: evidence for localization on the outer surface of the plasma membrane.

5'-Nucleotidase activity of rat liver plasma membrane is markedly inhibited by concanavalin A. Taken together with a unilateral pattern of labelling of concanavalin A binding sites with hemocyanin, the results indicate that an allosteric site of the enzyme is at the outer surface of the membrane.


Gap junctions between astrocytes during growth and differentiation in organ culture systems.

Fetal rat neocortex maintained in organ culture systems with the use of sponge foam matrices and millipore filter platforms undergoes growth and cytodifferentiation along classical neuronal and glial lines up to 36 days in vitro (DIV). Astrocytic differentiation is characterized by accumulation of 80-90 A glial filaments in the cell bodies and processes of astrocytes. Gap or nexus junctions closely resembling those formed in mammalian brain in situ are identified by 15 DIV. By 36 DIV, interastrocytic gap junctions are numerous and frequently join extensive lengths of adjacent glial plasma membranes. The results suggest that these organ culture systems may provide a favorable environment for the study of cellular structure and function of coupled neuroglia.


A scanning electron microscope study of the development of free axonal sprouts at the cut ends of dorsal spinal nerve roots in the rat.

Rat dorsal spinal nerve roots were cut and the tip on the ganglionic side of the cut was examined by scanning electron microscopy at 0, 7, 20 and 48 h after operation. Seven hours after cutting, free axonal sprouts had started to protrude from the cut end of the nerve. After 20 h the free sprouts were more profuse than at 7 h but were smaller and had a rougher surface. At both 7 and 20 h many of the sprouts consisted of a stalk 2-7 mum in diameter with a bulbous end 5-20 mum in diameter. A few branching sprouts were seen. At 48 h the sprouts were shrunken with a deeply furrowed surface. The significance of the surface structure of the sprouts is discussed.


Histochemical light microscopic study of catecholamine containing paraganglia in the human pelvis.

Histological and histochemical techniques have been employed to determine the structure and autonomic innervation of paraganglia located in the human pelvis. In foetal and early postnatal tissues, paraganglia formed rounded cellular masses which were frequently in company with the autonomic  nerves and ganglia of the urinary bladder and other pelvic viscera. The constituent cells contained only small amounts of cholinesterase and were unrelated to enzyme positive autonomic nerves; acetylcholinesterase containing nerves were occasionally observed in the capsule and the fibrous septa of the pelvic paraganglia. In early postnatal specimens, pelvic paraganglia frequently contained single or multiple "pacinian-like" corpuscles, each possessing a central region which was rich in both acetyl and pseudocholinesterase. These structures were rarely observed within autonomic ganglia and were absent 4 1/2 years post partum. By means of a histochemical technique, pelvic paraganglia were found to contain catecholamine which was attributed to the presence of relatively large quantities of noradrenaline. These observations have been discussed with particular reference to the results of other studies on the autonomic innervation of paraganglia.


Uptake of ferritin by the cephalopod optic gland.

Horse spleen ferritin, injected into the blood of the octopus, leaves the capillaries via pericyte junctions and windows. One hour after the administration, ferritin has entered the optic gland main cells; three hours later, it is accumulated in dense-bodies. The evidence for resorption supports earlier papers reporting that the ultrastructure of the organ is unusual for an endocrine gland.


The ultrastructure of the integument of the American eel, Anguilla rostrata.

The morphology and ultrastructure of the lateral body integument of the leptocephalus, glass eel, pigmented elver, and adult stages of the American eel, Anguilla rostrata, were examined with light and electron microscopy. The integument consists of an epidermis separated by a basal lamina from the underlying dermis. Three cell types are present in the epidermis in all stages. Filament-containing cells, which are the principal structural cell type, are increasingly numerous at each stage. Mucous cells, which secrete the mucous that compose the mucous surface coat, are also more numerous in each subsequent stage and are more numerous in the anterior lateral body epidermis than in the posterior lateral body epidermis of the adult. Club cells, whose function is unknown, are most numerous in the glass eel and pigmented elver. Chloride cells are common in the leptocephalus which is marine and infrequent in the glass eel. They are not present in the pigmented elver and adult which inhabit estuaries and freshwater. Lymphocytes and melanocytes are also present in some stages. The dermis comprises two layers: a layer of collagenous lamellae, the stratum compactum, and an underlying layer of loose connective tissue, the stratum spongiosum. There is a progressive increase in epidermal thickness at each stage which is paralleled by an increase in the thickness of the stratum compactum. Rudimentary scales are present in the dermis of the adult. The increase in the number of epidermal filament-containing cells, epidermal thickness and stratum compactum thickness is correlated with an increased need for protection from abrasion and mechanical damage as the eel moves from a pelagic, oceanic habitat to a benthic, freshwater habitat. The increase in mucous cell numbers is likewise correlated with an increased need for the protective and anti-bacterial action of the mucous surface coat in the freshwater environment.


A look into the cock-pit of the fly. The architecture of the lobular plate.

An anatomical investigation has been carried out on the third optic ganglion of the fly, Musca domestica. Two systems of giant units, the dendritic arborizations of which are arranged orthogonally relative to each other, dominate the neuropile of this ganglion. The elements of the two systems have been reconstructed using a graphical procedure based on histological sections. One system branches predominantly in the dorso-ventral direction, the other one in the anterior-posterior direction. Both systems of the giant units have a twin system composed of elements smaller in diameter and strictly parallel to the main units. The two systems have been termed the Vertical and Horizontal Systems. The elements of the two systems of fibers project into the periesophageal region where they come into contact with other descending elements. Electron microscopic investigations show that the two systems are post-synaptic at the level of the ganglion from which they originate. The horizontal system has been shown to be post and pre-synaptic in nature during its course in the mid-brain and ultimately presynaptic at its endings in the periesophageal ring. The peculiar geometric arrangement of the two anatomical systems of fibers suggests a precise function in relation to the visual world and in particular to the detection of the direction of motion. The accuracy of the structural pattern displayed by the giant units in the lobular plate seems to suggest that this optic ganglion represents the ultimate orderly projection of the external world in the brain of the fly. A short review of the electrophysiological data concerning this ganglion has been tentatively correlated with some behavioral data related to the visual orientation and fixation in insects.


The ultrastructure of paraganglia associated with the inferior mesenteric ganglia in the guinea-pig.

The paraganglia of the inferior mesenteric ganglia in the guinea-pig are composed of small chromaffin cells containing an abundance of granule-containing vesicles. The chromaffin cells are almost completely surrounded by satellite cells. In areas in which satellite cell processes do not intervene, the membranes of adjacent chromaffin cells are closely apposed and often form specialized attachment zones. The paraganglia contain a dense capillary network, the endothelial cells of which are often extremely attenuated and show areas of fenestration. The processes of chromaffin cells approach close to the capillary walls and are often bare of satellite cells covering on the side facing the capillary. Evidence has been obtained for the exocytotic release of the contents of chromaffin cell vesicles into pericapillary spaces. Synapses of cholinergic and noradrenergic axons are seen on the chromaffin cells. The cholinergic axons degenerate when the praganglia are decentralized, but the noradrenergic axons, which appear to arise from the local inferior mesenteric ganglia, remain intact. The results suggest that the paraganglia have an endocrine function.


Electron microscopic immunocytochemical demonstration of separate neurophysin-vasopressinergic and neurophysin-oxytocinergic nerve fibres in the neural lobe of the rat hypophysis.

By means of the unlabeled antibody peroxidase-antiperoxidase (PAP) technique at the electron microscopic level, it was demonstrated that the hormones of the neural lobe of the rat hypophysis are located in separate neurophysin-vasopressinergic and neurophysin-oxytocinergic nerve fibres. These observations confirm the results of our previous immunocytochemical studies at the light microscopic level.


Ultrastructural changes in spermatozoa of the brush-tailed possum, Trichosurus vulpecula (Marsupialia), during epididymal transit. Part II: The acrosome.

The acrosome in spermatozoa from the caput epididymidis of the Australian Brush-tailed possum, Trichosurus vulpecula, typically forms a cup-like structure, sitting on the anterior third of the dorsal surface of the nucleus. The base of the acrosomal 'cup' is narrowly separated from the nuclear surface, while the body of the 'cup' projects voluminously away from the nucleus. During epididymal transit these pronounced marginal extensions of the acrosome are retracted towards the nucleus, and the electron dense acrosomal material undergoes a process of compaction within the plasma membrane of the head to produce the convex ovate form of the definitive acrosome. During this process a variety of bizarre forms of the acrosome are produced before its final configuration is attained.


Spermiogenesis in the brush-tailed possum, Trichosurus vulpecula (Marsupialia). The development of the acrosome.

Acrosome development in the Australian Brush-tailed possum, Trichosurus vulpecula, displays a number of extraordinary features. This is particularly evident in the later stages of spermiogenesis, when the area of the nuclear surface bounded by the nuclear ring, and covered by the acrosome, is reduced considerable. As a result, the acrosomal material becomes located over its definitive position on the anterior third of the dorsal nuclear surface; in this process it is thrown into a series of folds, and a wide subacrosomal space is formed. Further changes around the time of spermiation result in the release of a spermatozoon in which a thin layer of acrosomal material is closely applied to the nucleus over the area of the definitive location of the acrosome, whilst its margins are greatly extended and project freely away from the nucleus. The latter feature does not appear to have been reported for the sperm of other mammals.


Second-order ocellar neurons in the brain of the honeybee (Apis mellifera).

Electrophoretic injection of Procion Yellow M-R4 into the ocellar tract of the worker bee has revealed the following: Two types of giant axon run from the lateral ocellus to the circumesophageal neuropile, where one branches ipsilaterally and the other contralaterally. A third type comes from the median ocellus and can be traced into the cervical connectives. The largest dendritic complex is in the circumesophageal neuropile; in addition, fiber endings have been demonstrated in the following areas: in the subretinal region, along the optic commissure, in the medulla interna, in the subesophageal ganglion and between the neurosecretory cells of the pars intercerebralis. -- The giant fibers are enclosed in a glial sheath. Three types of cell body are described. One is associated with the glia; another, larger cell type comprises giant-axon somata. The third type of cell is small, and cannot yet be identified. Some of the histological results are discussed with respect to the possible function of the ocellus.


An electrogenic sodium pump and baroreceptor function in normotensive and spontaneously hypertensive rats.

Postexcitatory depression (PED) and adaptation were examined in slowly adapting aortic baroreceptors of normotensive rats (NTR) and spontaneously hypertensive rats (SHR); an aortic arch-aortic nerve preparation in vitro was used. PED was elicited either mechanically by employing single or double pressure steps, or electrically by antidromic stimulation of the aortic nerve. During PED the axon of the receptor was capable of conducting action potentials and the receptor itself could respond to increased pressures. The relationship between duration of PED and number of impulses preceding it was hyperbolic. In NTR's and SHR's PED was abolished by ouabain or solutions containing no potassium, neither of which affected the steady state pressure-volume relationship of the aorta. These interventions, which are known to block electrogenic pumps, also lowered the pressure threshold and increased the curvature of the steady state pressure-frequency curve. Furthermore, lithium, another agent that blocks electrogenic pumps, also abolished PED. Thus, PED is attributed mainly to an electrogenic sodium pump which operates normally in baroreceptors. We found that adaptation from peak transient to steady state frequency did not appear to be altered significantly when the pump was blocked. Blockage of the pump by ouabain is responsible for the baroreceptor reflex effects elicited by this drug. We conclude that resetting and reduced sensitivity in SHR baroreceptors are not attributed to significant differences in electrogenic pump activity.