Decreased cell-mediated immunity and lack of skeletal problems in broiler chickens consuming diets amended with fusaric acid

Young female broiler chickens fed diets amended with 0, 35, 75, and 150 mg fusaric acid (FA)/kg diet for 3 weeks showed no aberrations in behavior, feed intake, weight gain, or appearance of the visceral organs. Furthermore, there was no correlation between the dietary concentration of FA and incidence of tibial dyschondroplasia and leg-shape deformities. Ash content of dry fat-free tibiae was not influenced by FA; thus, no rickets was present in these chickens. FA enhanced the humoral response to sheep erythrocytes but significantly reduced cell-mediated cutaneous response to phytohemagglutinin-P.

Increased expression of nitric oxide synthase in hypothalamic neuronal regeneration

This investigation deals with the histochemical and scanning electron microscopic (SEM) correlates that depict regeneration of the neurohypophyseal system that may be nitric oxide dependent following hypophysectomy in the rodent hypothalamus. NOS histochemistry and correlative SEM were employed to establish the rates of regrowth and appearance of NOS-positive supraoptic (SON) and paraventricular (PVN) neurites and their cell bodies following hypophysectomy. NOS activity increased significantly in SON and PVN neuronal perikarya and regenerating axons by 2 weeks. NOS-positive neurites were observed to regrow into the adjacent median eminence and insinuate into the lumen of the third cerebral ventricle. By 4 weeks posthypophysectomy, NOS staining of SON and PVN neurons and their regrown neurites had returned to normal control levels. Despite this fact, large complexes of apparent magnocellular neurites remained upon the floor of the third cerebral ventricle as observed with SEM. These observations support the hypothesis that NO may play a fundamental role in the process of regeneration, plasticity, and retargeting of SON and PVN axons following injury.

Development of nitric oxide synthase expression in the superficial dorsal horn of the rat spinal cord

Development of nitric oxide synthase (NOS) expression in the superficial dorsal horn of the rat spinal cord was studied using NADPH diaphorase histochemistry. At birth, no positive staining was seen in the superficial laminae of the cord. A week later, a few small positive neurons and fibers were seen in presumptive lamina II. The adult pattern of NOS expression was evident by the end of the third postnatal week.

Localization of metallothionein in breast carcinomas. An immunohistochemical study

Metallothionein (MT) is a cysteine-rich, low molecular weight protein that binds zinc, copper, and cadmium. It is present in a number of normal cells including hepatocytes particularly during fetal and early postnatal life. It has been suggested that developmental profile of MT is similar to other oncofetal gene products and hence, it could be used as a marker for aggressive tumour behaviour. In order to test that hypothesis, we used a monoclonal antibody to MT and immunohistochemically evaluated formalin-fixed, paraffin-embedded tissues from 79 breast carcinomas. In non-neoplastic breast tissue, a strong nuclear and cytoplasmic staining was observed in myoepithelial cells. Positive staining for MT was present in 35 (44%) of breast carcinomas. In most positive cases, nuclear, or both nuclear and cytoplasmic staining was seen. All positive tumours were invasive ductal carcinomas, including a medullary and a metaplastic carcinoma. None of the mucinous, lobular, or intraductal papillary carcinomas reacted for MT. A statistically significant association was found between MT immunostaining and histological grade (P < 0.01) as well as with nuclear grade (P < 0.01). We also observed an inverse relationship between MT staining and oestrogen receptor content of tumours (P < 0.01). Similarly, a statistically significant association was found between moderate and strong MT immunostaining and decreased overall survival and shorter disease-free survival (P < 0.01). MT immunostaining was also predictive of a worse prognosis in the subgroup of lymph node negative (P < 0.001) and oestrogen receptor negative patients (P < 0.01). No statistically significant association was found between MT staining and size of tumour or the presence of lymph node metastasis. We conclude that MT staining may be a useful marker of less differentiated and more aggressive carcinomas of the breast.

Inhibition of nitric oxide synthase reduces motoneuron death due to spinal root avulsion

Our previous studies have shown that nitric oxide synthase (NOS) can be induced in motoneurons after spinal root avulsion lesion and the lesion-induced NOS is coincident with the death of the injured neurons. The present study examined whether the death of injured motoneurons can be prevented by inhibition of NOS. Nitroarginine, a specific inhibitor of NOS, was injected into adult rats which underwent spinal root avulsion. At a dose of 50 mg/kg/day, nitroarginine significantly inhibited the activity of lesion-induced NOS and significantly reduced the death of motoneurons due to spinal root avulsion. Results of the present study indicate that NO, produced by lesion-induced NOS, may be involved in and responsible for the neuronal death after traumatic injury.

Tibial dyschondroplasia of chickens induced by Fusarochromanone, a mycotoxin

Chicks were fed for 3 weeks a practical broiler starter diet amended with fusarochromanone (FC), a mycotoxin. In Hubbard broiler chicks, the highest test dose of FC (75 ppm) suppressed body weight by 33% and humoral response to sheep erythrocytes by 34% to 50%, and increased the incidence of tibial dyschondroplasia (TD) to 100%. The intermediate dose (35 ppm) significantly increased the incidence of TD in both types of broiler chicks (Hubbard and Indian River), but its effect on humoral response to sheep erythrocytes was not consistent across several experiments. A minimum dietary concentration greater than 20 ppm was required to significantly increase the incidence of TD. Excessive dietary copper or zinc (200 ppm) alleviated the effect of FC on TD. However, activities of copper-dependent ceruloplasmin and superoxide dismutase was not affected by FC. Cartilage mineral profiles in FC- or Thiram-induced TD differed from that of 1-day-old hypertrophic embryonic cartilage core (less K and Mn). FC did not induce TD in leghorn chicks.

Expression of nitric-oxide synthase (NOS) in injured CNS neurons as shown by NADPH diaphorase histochemistry

Recent studies have implicated nitric oxide (NO) in several mechanisms related to neuronal degeneration and synaptic plasticity. In the present study, two models of traumatic neuronal injury were used to examine the expression of NOS following neuronal injury and its relationship to axonal sprouting and neuronal degeneration. It was found that NOS is induced in a week of axonal injury in neurons that are normally NOS-negative. Spinal motoneurons express the enzyme after ventral root avulsion, but not after ventral root transection. Neurons of the nucleus dorsalis of the spinal cord express NOS after ipsilateral spinal cord hemisection. These two models provide information about the time course of NOS expression in injured neurons and the opportunity in future studies to determine the role of NOS and its product, NO, in CNS injury. Observations from the present study suggest that early NOS expression seems to be associated with axonal sprouting and growth. Interestingly, though, the neurons expressing lesion-induced NOS ultimately die. Whether NOS expression in these cells is related to their death is currently under investigation.

Evidence for amelioration of cellular damage in ischemic rat brain by radix salviae miltiorrhizae treatment--immunocytochemistry and histopathology studies

The changes of somatostatin (SS)--like immunoreactive cells and morphology were observed in the models of ligation of right MCA and bilateral ligation of CCA respectively. The results showed: (1) a decline of SS immunoreactive nerve cell profiles in right cerebral cortex after 3h ligation of MCA as compared with left cerebral cortex and sham-operated group, while no significant difference was found between RSM-treated and saline-treated groups; (2) selective ischemic cell changes in cerebral cortex, hippocampus and caudate nucleus after 3h ligation of CCA. The changes included shrinkage and condensation of perikaryon, nuclear pyknosis, cytoplasmic eosinophilia in some neurons. The ischemic changes were more severe in saline-treated group than RSM-treated group. The experiments indicated that the selective ischemic cell changes could be improved by RSM, suggesting that treatment to modulate SS metabolism may be indicated after ischemic insults.

Nicotine-induced analgesia in rats: the role of calcium and the diversity of responders and nonresponders

Following a single dose of nicotine, (NIC, 1 mg/kg s.c.), 60% of tested rats revealed significant antinociception as measured by the tail-flick (TF) test, and were classified as responders, with those in which TF latencies did not change, nonresponders. The following experiments were carried out one week later. In nonresponders, pretreatment with ethylenediaminetetraacetic acid (EDTA, 250 microM/kg s.c. four times every 15 min) followed by 1 mg NIC, produced significant analgesia in 50% of rats, to the same magnitude as did nicotine alone (1 mg) in responders. The other 50% of rats which failed to respond to EDTA pretreatment, all revealed similar analgesia following the higher dose of NIC (1.5 mg/kg s.c.), with similar side effects, as generally observed in responders. In responders, pretreatment with CaCl2 (1.5 mM/kg s.c.) completely abolished NIC (1 mg/kg s.c.)--induced analgesia in all rats. Our data provide stronger evidence and a further verification that EDTA potentiates, whereas CaCl2 completely abolishes, nicotine-induced analgesia in rats; supporting our hypothesis of the involvement of calcium ions in this effect.

Human cerebrospinal fluid protein database: edition 1992

Two-dimensional electrophoresis maps of human cerebrospinal fluid proteins are presented in the form of labeled images. 931 protein spots are identified in spinal fluid from a normal volunteer. Distinct spots that represent variants of the same protein, especially posttranslational modifications, are estimated to reduce the 931 different spots to < 200 different proteins. 248 spots of 29 protein groups have been identified and are indicated on enlargements of specific gel regions. The distribution of protein abundance, mass, charge and shape characteristics of these normal 931 spinal fluid spots are graphically profiled. Analysis of the shape parameter "vertical height: width ratio" reveals that a ratio > 3.5 correlates with glycoproteins, enabling their identification simply by image analysis. Proteins that are not present on the normal map, but appear in spinal fluid in patients with schizophrenia and Creutzfeldt-Jakob disease are illustrated on additional maps.

Differential effects of cyclo-oxygenase and thromboxane synthetase inhibition on ventilation-perfusion relationships in acid aspiration-induced acute lung injury

Cyclo-oxygenase metabolites are important regulators of pulmonary vascular and airway tone and may act to regulate ventilation-perfusion (VA/Q) relationships. Hypoxemia that follows aspiration of gastric acid is associated with increased venous admixture, and plasma levels of thromboxane (TX) B2 and 6-keto-PGF2 alpha are increased after experimental acid-induced acute lung injury. The present study was designed to determine the effects of cyclo-oxygenase metabolites on VA/Q relationships in canine acid aspiration. Eighteen anesthetized dogs received 0.2 mL/kg 0.1 N HCl intratracheally; six were pretreated with ibuprofen (IBU), a cyclo-oxygenase inhibitor, 12.5 mg/kg IV, and six other dogs received OKY-046 (OKY), a TX synthetase inhibitor, 0.5 mg/kg IV. The remaining six animals (ACID) served as controls. Continuous distributions of ventilation and perfusion were evaluated with the multiple inert gas elimination technique. Within 30 minutes, acid injury resulted in significant (p < 0.05) decreases in PaO2 from baseline values by 44.7 +/- 5.4 and 47.6 +/- 4.8 mm Hg in the ACID and OKY groups, respectively. Although decreased, the change in PaO2 of 21.0 +/- 4.8 mm Hg in IBU animals was significantly (p < 0.05) attenuated in comparison with the other groups. Ibuprofen increased pulmonary vascular resistance, attenuated perfusion to shunt and low VA/Q areas, and reduced ventilation to unperfused areas for the first 2 hours after acid injury (all p < 0.05), whereas OKY exacerbated hypoxemia and VA/Q inequality.(ABSTRACT TRUNCATED AT 250 WORDS)

Organization of the serotonergic innervation of spinal neurons in rats--I. Neuropeptide coexistence in varicosities innervating some spinothalamic tract neurons but not in those innervating postsynaptic dorsal column neurons

Previous studies have suggested that peptides such as substance P and thyrotropin-releasing hormone coexist with serotonin in the same varicosities in the ventral horn and intermediate gray of the spinal cord in rat. However, coexistence of these peptides with serotonin is rare in fibers in the superficial dorsal horn. Since it has been proposed that serotonergic fibers in the superficial dorsal horn act to modulate nociception, it was hypothesized that the serotonergic neurons that contain neither substance P nor thyrotropin-releasing hormone might constitute a specifically antinociceptive subset of serotonergic neurons. This being the case, it would be expected that different types of serotonergic neurons innervate nociceptive and non-nociceptive spinal neurons. In order to test this hypothesis, a group of cells that include nociceptive neurons (spinothalamic tract neurons) and a group of predominantly non-nociceptive neurons (postsynaptic dorsal column neurons) in the spinal cord of rat were retrogradely labeled. Sections of the spinal cord containing retrogradely labeled spinothalamic tract or postsynaptic dorsal column neurons were stained for serotonin and either substance P or thyrotropin-releasing hormone using two-color immunohistochemistry. A retrogradely labeled cell was classified as "apposed" if there was no discernible distance between an immunohistochemically labeled varicosity and the cell. Eighty per cent of spinothalamic tract and 83% of postsynaptic dorsal column profiles were apposed by serotonin-immunoreactive varicosities in the spinal cord. Thirty-one per cent of the spinothalamic tract profiles that were apposed by serotonergic varicosities were apposed by serotonergic varicosities that were also stained for thyrotropin-releasing hormone. The distribution of the latter spinothalamic neurons was similar to that reported for spinothalamic tract neurons responsive to joint movement. In addition, at least 63% of the spinothalamic tract profiles which were apposed by serotonergic varicosities were apposed by "serotonin-only" varicosities, including most spinothalamic tract neurons in the marginal zone, suggesting that at least some "serotonin-only" neurons are antinociceptive. However, contrary to the hypothesis, at least 94% of the postsynaptic dorsal column profiles apposed by serotonergic varicosities were apposed by "serotonin-only" varicosities. These findings suggest that there may be a relationship between the sensory modality to which a spinal neuron responds and the type of serotonergic innervation it receives. However, it appears that "serotonin-only" neurons may not constitute a specifically antinociceptive category of serotonergic neurons.

The effect of radix Salviae miltiorrhizae on the changes of ultrastructure in rat brain after cerebral ischemia

The effect of RSM on ultrastructural alterations of the cortical, hippocampal and caudate neucleus areas brought about by forebrain ischemia in rats were studied. In both RSM-treated and saline-treated groups the ischemic damage was detected in nearly all animals three hours after bilateral common carotid artery ligation, while it was much more mild in RSM-treated animals. The ultrastructural changes consisted of swollen mitochondria, partial loss of cristae, dilatation of rough endoplasmic reticulum and Golgi's complex. In addition, some dark neurons were present, capillary endothelial cells and processes of astrocytes were swollen and active pinocytosis appeared in the endothelial cells. Their presence was most severe in the hippocampus region and the least in the caudate nuclear area. No ultrastructural changes exhibited in the sham-operated animals. The findings of the present experiment demonstrate that RSM can reduce ultrastructural abnormalities of cerebral ischemia and are also direct evidence of the protective effect of RSM on cerebral ischemia.

Identification of neurons expressing thyrotropin releasing-hormone receptor mRNA in spinal cord and lower brainstem of rat

The distribution of mRNA coding for a pituitary thyrotropin releasing-hormone (TRH) receptor was examined on sections of spinal cord and lower brainstem of rat using in situ hybridization. Hybridization signals were observed over large neurons in the ventral horn in cervical, thoracic, and lumbar segments of spinal cord, and over neurons in the motor nuclei of the lower brainstem. Although significant thyrotropin-releasing hormone binding has been reported in the superficial dorsal horn, only background levels of hybridization were observed over neurons in this region. These findings suggest that mRNA coding for thyrotropin-releasing hormone receptor is expressed in some spinal and brainstem motor neurons. Since many of these neurons are innervated by TRH-containing afferents, TRH may exert a direct effect upon at least some of these cells.

K stimulation of ATPase activity associated with the chloroplast inner envelope

Studies were conducted to characterize ATPase activity associated with purified chloroplast inner envelope preparations from spinach (Spinacea oleracea L.) plants. Comparison of free Mg(2+) and Mg.ATP complex effects on ATPase activity revealed that any Mg(2+) stimulation of activity was likely a function of the use of the Mg.ATP complex as a substrate by the enzyme; free Mg(2+) may be inhibitory. In contrast, a marked (one- to twofold) stimulation of ATPase activity was noted in the presence of K(+). This stimulation had a pH optimum of approximately pH 8.0, the same pH optimum found for enzyme activity in the absence of K(+). K(+) stimulation of enzyme activity did not follow simple Michaelis-Menton kinetics. Rather, K(+) effects were consistent with a negative cooperativity-type binding of the cation to the enzyme, with the K(m) increasing at increasing substrate. Of the total ATPase activity associated with the chloroplast inner envelope, the K(+)-stimulated component was most sensitive to the inhibitors oligomycin and vanadate. It was concluded that K(+) effects on this chloroplast envelope ATPase were similar to this cation's effects on other transport ATPases (such as the plasmalemma H(+)-ATPase). Such ATPases are thought to be indirectly involved in active K(+) uptake, which can be facilitated by ATPase-dependent generation of an electrical driving force. Thus, K(+) effects on the chloroplast enzyme in vitro were found to be consistent with the hypothesized role of this envelope ATPase in facilitating active cation transport in vivo.

Stromal pH and Photosynthesis Are Affected by Electroneutral K and H Exchange through Chloroplast Envelope Ion Channels

Potassium movement across the limiting membrane of the chloroplast inner envelope is known to be linked to counterex-change of protons. For this reason, K(+) efflux is known to facilitate stromal acidification and the resultant photosynthetic inhibition. However, the specific nature of the chloroplast envelope proteins that facilitate K(+) fluxes, and the biophysical mechanism which links these cation currents to H(+) counterflux, is not characterized. It was the objective of this work to elucidate the nature of the system regulating K(+) flux linked to H(+) counterflux across the chloroplast envelope. In the absence of external K(+), exposure of spinach (Spinacia oleracea) chloroplasts to the K(+) ionophore valinomycin was found to increase the rate of K(+) efflux and H(+) influx. These data were interpreted as suggesting that H(+) counterexchange must be indirectly linked to movement of K(+) across the envelope. Studies using the K(+) channel blocker tetraethylammonium indicated that K(+) likely moves, in a uniport fashion, into or out of the stroma through a monovalent cation channel in the envelope. Blockage of K(+) efflux from the stroma by exposure to tetraethylammonium was found to restrict H(+) influx, further substantiating an indirect linkage of these cation currents. Further studies comparing the effect of exogenous H(+) ionophores and K(+)/H(+) exchangers suggested that K(+) uniport through this ion channel likely is the main endogenous pathway for K(+) currents across the envelope. These experiments were also consistent with the presence of a proton channel in the envelope. Movement of H(+) through this channel was speculated to be regulated and rate limited by an electroneutral requirement for K(+) countercurrents through the separate K(+) uniport pathway. K(+) and H(+) fluxes across the chloroplast envelope were envisioned to be interrelated via this mechanism. The significant effect of cation currents across the envelope, as mediated by these channels, on photosynthetic capacity of the isolated chloroplast was also demonstrated.

Decreased immunological responses by wortmannin-containing rice culture of Fusarium oxysporum and by purified wortmannin in avian species

Immunological assays were performed in young chicken and duck after they had been fed wortmannin-containing culture of Fusarium oxysporum or purified wortmannin for 2 weeks. The culture significantly decreased humoral response to sheep red blood cell, cell-mediated cutaneous hypersensitivity to phytohemagglutinin and phagocytic activity in isolated peritoneal exudate adherent cells, but only when the concentration was high enough to cause concurrent reduction in body weight gain and hematocrit. Increased dietary metabolizable energy and protein did not affect the toxicity of the culture. On the other hand, purified wortmannin (1 mg/kg diet) significantly inhibited the aforementioned immunological responses prior to the adverse effects on body growth and hematocrit. The data strongly indicate that wortmannin is an immunotoxic substance. The possibility that macrophage is the primary target cell type is discussed.

Effect of advanced age and medical disease on the outcome of microvascular reconstruction for head and neck defects

During the 5-year period from July 1984 to 1988, 72 patients over the age of 50 underwent microvascular free tissue transfers for head and neck reconstruction. There were 22 patients aged 50-59 years, 31 patients aged 60-69 years, and 19 patients aged 70-79 years. Seventy of these procedures (97%) were done at the time of ablative surgery utilizing a two-team approach. There was 1 total flap loss for a flap viability rate of 99% (73/74). There were 46 complications in 40 patients: 21 surgical and 25 medical. Twelve of the surgical complications required reoperation for a major surgical complication rate of 16%. Major medical complications developed in 12 patients (16%). Medical complications more commonly were observed in patients aged 60-69 years who had significant preoperative comorbidity and were classified as ASA class 3 or greater. There were 5 postoperative deaths for a mortality rate of 7%. Advanced chronologic age does not compromise the technical success of microsurgical free tissue transfer in the elderly patient with head and neck cancer. The risk of medical complications is significant and is directly related to concurrent illness of the individual patient rather than to age alone.

[Effects of ibuprofen and OKY-046 on ventilation perfusion distribution in acute respiratory failure]

Hydrochloric acid was injected into the trachea to produce acute respiratory failure in 18 anesthetized dogs. Six dogs were pretreated with ibuprofen (12.5 mg/kg), six dogs were given OKY-046 (0.5 mg/kg), and the remaining six were taken as controls. Distribution of ventilation-perfusion was evaluated by inert gas elimination technique. Acid aspiration caused a prompt decline in PaO2 with an increased perfusion to shunt and low VA/Q lung regions. Pretreatment with ibuprofen reduced pulmonary blood flow to shunt and low VA/Q regions for the first 2 hours after acid aspiration and attenuated hypoxemia, causing an increase in PVR. However, OKY-046, a thromboxane synthetase inhibitor, did not ameliorate acid-induced VA/Q mismatching and hypoxemia.

Lidocaine and ATPase inhibitor interaction with the chloroplast envelope

Photosynthetic capacity of isolated intact chloroplasts is known to be sensitive to K(+) fluxes across the chloroplast envelope. However, little is known about the system of chloroplast envelope proteins that regulate this K(+) movement. The research described in this report focused on characterizing some of the components of this transport system by examining inhibitor effects on chloroplast metabolism. Digitoxin, an inhibitor of membrane-bound Na(+)/K(+) ATPases, was found to reduce stromal K(+) at a range of external K(+) and inhibit photosynthesis. Scatchard plot analysis revealed a specific protein receptor site with a K(m) for digitoxin binding of 13 nanomolar. Studies suggested that the receptor site was on the interior of the envelope. The effect of a class of amine anesthetics that are known to be K(+) channel blockers on chloroplast metabolism was also studied. Under conditions that facilitate low stromal pH and concomitant photosynthetic inhibition, the anesthetic, lidocaine, was found to stimulate photosynthesis. This stimulation was associated with the maintenance of higher stromal K(+). Comparison of the effects on photosynthesis of lidocaine analogs which varied in lipophilicity suggested a lipophilic pathway for anesthetic action. The results of experiments with lidocaine and digitoxin were consistent with the hypothesis that a K(+) channel and a K(+)-pumping envelope ATPase contribute to overall K(+) flux across the chloroplast envelope. Under appropriate assay conditions, photosynthetic capacity of isolated chloroplasts was shown to be much affected by the activity of these putative envelope proteins.

Surface Charge-Mediated Effects of Mg on K Flux across the Chloroplast Envelope Are Associated with Regulation of Stromal pH and Photosynthesis

Studies of Spinacia oleracea L. were undertaken to characterize further how Mg(2+) external to the isolated intact chloroplast interacts with stromal K(+), pH, and photosynthetic capacity. Data presented in this report were consistent with the previously developed hypothesis that millimolar levels of external, unchelated Mg(2+) result in lower stromal K(+), which somehow is linked to stromal acidification. Stromal acidification directly results in photosynthetic inhibition. These effects were attributed to Mg(2+) interaction (binding) to negative surface charges on the chloroplast envelope. Chloroplast envelope-bound Mg(2+) was found to decrease the envelope membrane potential (inside negative) of the illuminated chloroplast by 10 millivolts. It was concluded that Mg(2+) effects on photosynthesis were likely not mediated by this effect on membrane potential. Further experiments indicated that envelope-bound Mg(2+) caused lower stromal K(+) by restricting the rate of K(+) influx; Mg(2+) did not affect K(+) efflux from the stroma. Mg(2+) restriction of K(+) influx appeared consistent with the typical effects imposed on monovalent cation channels by polyvalent cations that bind to negatively charged sites on a membrane surface near the outer pore of the channel. It was hypothesized that this interaction of Mg(2+) with the chloroplast envelope likely mediated external Mg(2+) effects on chloroplast metabolism.

No difference in day-night serum melatonin concentration after pineal grafting into the third cerebral ventricle of pinealectomized rats

Serum melatonin concentration and its day-night difference in pinealectomized, stereotaxically grafted rats with pineal transplants was examined. The nighttime serum melatonin concentration increased significantly only in pinealectomized rats that received two pineal transplants. In neither pinealectomized rats receiving two pineal glands and one cotransplant of superior cervical sympathetic ganglion nor pinealectomized-ganglionectomized rats receiving two pineal transplants was there a demonstrable increased in serum melatonin concentration. Although some pineal transplanted hosts demonstrated increases in serum melatonin concentration, there was no day-night variation in serum melatonin concentration. This may be due to a number of mitigating factors. Pineal grafts may not receive the appropriate functional reinnervation from the host brain due to the location of the transplantation in the cerebral ventricle or due to lack of sufficient time for the growth of invading host neurites.

The effect of radix Salviae Miltiorrhizae (RSM) on substance P in cerebral ischemia--animal experiment

The levels of substance P (SP) in rat brains were assayed in 64 rats. Bilateral common carotid artery ligation was done in 49 rats. Half an hour before ligation, 25 rats were given 10 g/kg of RSM; 24 rats were given the same volume of normal saline as controls. Sham operation was done in 15 rats. Half an hour and 3 hours after cerebral ischemia, the rats were quickly decapitated. SP concentration was assayed in the cerebral cortex, caudate nucleus and brain stem. In saline-treated animals, the SP level of caudate nucleus at 3-hour group was significantly decreased as compared with the 0.5-hour group and sham-operated group respectively. No significances were found among RSM-treated groups and sham-operated groups. The SP levels were shown: brain stem greater than caudate nucleus greater than cerebral cortex. The preliminary results suggest that SP may be involved in the pathophysiologic procedures of cerebral ischemia and RSM may attenuate the dysfunction of SP during cerebral ischemia.

Short acting soft mydriatics

Three soft drug analogs of atropine have been tested for mydriatic activity in rabbits' eyes and their in vitro metabolic pathway has been investigated in rat, rabbit and human blood. The three soft drugs were found to produce an equieffective mydriatic activity to atropine and tropicamide. At equieffective concentrations, their durations were shorter with AUC's 12-21% that of 0.25% atropine and 44-80% that of 0.2% tropicamide. The untreated control eyes were observed to dilate after unilateral ocular administration of atropine, but not with unilateral soft drug treatment. In vitro stability studies showed that the soft ethyl analog was less stable in rat blood and rat liver homogenate than in rabbit or human blood. The metabolic product of the soft ethyl derivative in biological media was proven to be the corresponding inactive acidic metabolite predicted by the soft drug design. The ultrashort durations and the potentially nontoxic systemic properties of the soft mydriatics offer promise for use in ophthalmoscopy and in other ocular procedures where a short acting anticholinergic type of mydriatic would be indicated.

The investigation of antiepileptic action of qingyangshen (QYS)--effect of QYS on the concentrations of neuropeptides in rat brain

The concentrations of central neuropeptides, somatostatin (SS) and substance-P (SP), were determined in the different brain regions of young-aged male rats after a long-term administration of anticonvulsants Qingyangshen (QYS), Diphenylhydantoin (DPH), and Carbamazepine (CBZ). The results were compared with Pentylenetetrazol (PTZ)-induced seizure model and normal saline-treated controls. No effects of QYS on the concentrations of SS and SP were found in the rats of four-week or eight-week group. Both of DPH and PTZ increased the SS levels in the midbrain of rats in four-week group. DPH, CBZ, and PTZ also increased the SP levels in the cerebral cortex, striatum, and brain stem of rats in eight-week group. Our present data indicated that the central neuropeptides SS and SP were involved in the processes of epilepsy and antiepilepsy. Since QYS did not influence the contents of SS and SP after a long-term administration, it suggested that the anticonvulsant mechanism of QYS may be different from those of DPH and CBZ, i.e. it may be not due to its effect on the central neuropeptide pathway.

Crystal-induced inflammation: studies of the mechanism of crystal-membrane interactions

Studies of the interactions of monosodium urate monohydrate (MSUM) crystals and calcium pyrophosphate dihydrate triclinic (CPPD) crystals with biomembranes have been reviewed. Crystal-membrane binding and crystal-induced membranolysis have been studied using human erythrocytes as a model membrane system. The extent of MSUM-membrane binding was determined by incorporating a hydrophobic, fluorescent probe into the membranes, centrifugation to separate free membranes from membranes with bound crystals and quantitation of free membranes by measuring the total fluorescence intensity. The ability of MSUM and CPPD to hemolyse red cells was used as a measure of the membranolytic potential of the crystals. Fluorescence polarization studies showed that MSUM-membrane binding resulted in fluidization of the membrane. Cross-linking of the membrane proteins of the erythrocyte or the presence of divalent cations in the incubation medium inhibited MSUM induced hemolysis. These findings were explained by hypothesizing a "pore" model mechanism for MSUM induced membranolysis as follows. Binding of crystals to membranes induces the redistribution of transmembrane proteins into clusters or aggregates leading to "pore" formation. The "pores" permit the leakage of low molecular weight soluble compounds and ions acoss the membrane which is followed by osmotic rupture of the membrane.

"Dry lithotripsy" by a simple modification of the Chinese lithotripter KDE-1

We report on the improved technique upon a water bath lithotripter. With a simple water balloon device added to the Chinese KDE-1 Type water bath lithotripter, an extracorporeal shock wave dry lithotripter has been developed. From June to December 1988, there were 300 cases of upper urinary tract calculi and gallbladder stone treated with this machine with excellent results and no severe complications. The improved technique would be made reference to change old water bath machines into dry (water balloon) machines.

Cohort and case-control analyses of workers exposed to vinyl chloride: an update

The mortality in a cohort of workers at a vinyl chloride polymerization plant has been updated, extending the period of observation in the original study from 1974 to 1986. Workers at this plant may have been exposed to vinyl chloride monomer and/or polyvinyl chloride dust, or may have had no exposure to either substance. Seventy-six percent of the work force worked in jobs with potential exposure to vinyl chloride monomer. Among the total cohort, statistically significant excess risks were observed for liver, lung, and brain cancer. For the subcohort of workers exposed to vinyl chloride monomer, the standardized mortality ratio (SMR) for liver cancer was 333 (90% confidence interval (CI) 202 to 521). However, there were no significant excesses of either brain (SMR = 145, 90% CI 78 to 249) or lung cancer (SMR = 115, 90% CI 96 to 141). To investigate dose response, nested case-control studies for liver, brain, and lung cancer were conducted among the total cohort (including the nonexposed). For these studies there were two exposure variables, cumulative dose of vinyl chloride monomer and cumulative dose of polyvinyl chloride dust. Cumulative dose was defined as the product of level and duration of exposure. The only significant association between disease risk and cumulative dose was for liver cancer and cumulative dose of vinyl chloride monomer. Further division of the liver cancers into angiosarcoma (n = 12) and other liver cancers (n = 7), based on review of death certificates and medical records, showed that the dose response existed only for angiosarcomas.

Spontaneous noncardiac chest pain. Evaluation by 24-hour ambulatory esophageal motility and pH monitoring

Noncardiac chest pain can be a diagnostic dilemma because patients rarely experience spontaneous chest pain in the laboratory. Therefore, we studied 24 patients with chronic, daily, substernal chest pain with a prototype 24-h ambulatory esophageal motility and pH system. Spontaneous chest pain episodes were correlated with pH less than 4 and abnormal motility changes (mean amplitude and duration, maximum amplitude and duration, or percentage of abnormal peristalsis) defined as exceeding the patient's normal esophageal motility pattern. Twenty-two patients experienced a total of 92 spontaneous chest pain episodes. Eleven chest pain episodes (12%) occurred during abnormal motility, whereas 18 episodes (20%) were associated with pH less than 4 and four episodes (4%) had both abnormalities. The majority of chest pain episodes, 59 events (64%), did not have any association with motility or pH. Abnormal maximum duration and amplitude were the motility changes most frequently associated with chest pain. Overall, 13 of 22 patients (59%) had at least one chest pain episode correlating with abnormal motility or pH (range 33%-100%). Therefore, we conclude that ambulatory esophageal motility and pH monitoring is useful in the evaluation of noncardiac chest pain. pH abnormalities (20%) are more commonly associated with chest pain than motility abnormalities (12%). However, the majority of chest pain episodes (64%) did not correlate with either abnormality and may be the result of lowered esophageal pain threshold for distention, i.e., the "irritable esophagus."

Immune and bone properties of chicks consuming corn contaminated with a Fusarium that induces dyschondroplasia

A study was conducted to contrast the dyschondroplasia-inducing capability of several species of Fusarium with that of the natural fungi found in poultry diets and litter. Day-old broiler chicks were fed pure corn cultures of specific fungal isolates for 3 weeks. Humoral immunity to sheep red blood cells (SRBC), body weight, valgus and varus leg deformities, incidence of dyschondroplasia, and mechanical properties of the tibiotarsi were examined. F. equiseti #15 was the only fungal isolate to induce dyschondroplasia to any significant degree, which confirmed previous work in Minnesota. This isolate also suppressed growth rate and humoral immunity, although dyschondroplasia sometimes did occur without associated immunosuppression and growth depression. Bone strength of the tibiotarsal diaphysis was normal, and gross lesions of valgus and varus leg deformities did not appear to be related to the incidence of dyschondroplasia in the 3-week-old chicks.

Evidence that heme d1 is a 1,3-porphyrindione

Heme d1 is the noncovalently associated heme prosthetic group of the bacterial nitrite reductase known as cytochrome cd1. Additional evidence has been obtained in support of a dioxoisobacteriochlorin, or 1,3-porphyrindione, skeleton for this heme. The new data include the natural abundance 13C NMR spectrum of the free base methyl ester derivative of d1, mass spectrometric determinations of the molecular mass of the free base methyl ester and the Cu and the Zn chelates, visible and 1H NMR spectral comparisons between d1 and synthetic porphyrindione model compounds, and the isolation and characterization of several byproducts formed during the purification of the free base methyl ester of d1. The accumulated evidence strongly supports the following structure for the skeleton of d1: 1-oxo-2-methyl-2'-acetyl-3-oxo-4-methyl-4'-acetyl-5-methyl-6-acrylyl+ ++-7- propionyl-8-methylporphyrin.

The porphinedione structure of heme d1. Synthesis and spectral properties of model compounds of the prosthetic group of dissimilatory nitrite reductase

In an attempt to verify the recent proposal that the heme d1 prosthetic group isolated from cytochrome cd1 is not a chlorin, but a dioxo-isobacteriochlorin (Chang, C. K. (1985) J. Biol. Chem. 260, 9520-9522), a model dioxo-isobacteriochlorin has been synthesized possessing a pi-electron system exactly identical to that as proposed. The presence of an acrylic acid substituent strongly perturbs the absorption spectrum of the chromophore and produces a visible spectrum virtually indistinguishable from that of the iron-free heme d1. Based on this finding, buttressed by additional spectral correspondence between the model iron heme and heme d1, we conclude that the proposed diketo ring structure is indeed correct, and the trivial names "dioneheme" and "acryloporphyrindione" are suggested for heme d1 and the demetallated macrocycle, respectively.

Chemical softening and wear of dental composites

The purpose of this work was to determine the influence of chemical food-simulating liquids on the wear of various commercial dental composite restoratives. In many cases, pre-conditioning the restoratives in these liquids for one week produced swelling of the polymer matrix and considerable surface damage. The resulting degradation reduced the hardness and enhanced the wear as measured by a pin-and-disc apparatus. Four kinds of commercial composites were investigated: a conventional quartz-filled, a strontium-glass-filled, a visible-light-activated, and a microfilled composite. The liquids employed were heptane and several aqueous solutions of ethanol with solubility parameters, delta, ranging from delta = 1.5 to 4.8 X 10(4) J1/2m-3/2. With all restoratives, the decline in hardness during pre-conditioning maximized at about delta = 3 X 10(4), which corresponds to a 75% ethanol solution. The wear behavior was considerably more complicated and variable, as discussed in the text. For the most part, the increase in wear rate from pre-conditioning corresponded to the fall in hardness. A notable exception was for the strontium-glass-filled composite pre-conditioned in pure water. Here the wear was enhanced considerably, with no decrease in hardness. In this case, the degradation mode is assumed to be different from the others in that it is attributed to stress corrosion of the glass filler.

Effect of maturation and age on lymphocyte proliferation induced by A23187 through an interleukin-independent pathway

Lymphocyte proliferation induced by lectins declines drastically with age. It has been suggested that the reduction of interleukin production by lymphocytes from old individuals is responsible for the decline in proliferation. In this study, lymphocyte proliferation was stimulated by the calcium ionophore, A23187. A23187 induced the proliferation of spleen lymphocytes from rats through an interleukin-independent pathway; depletion of spleen lymphocytes of macrophages, addition of exogenous interleukin 2 (IL 2), and addition of anti-IL 2 monoclonal antibodies had no effect on the proliferation stimulated by A23187. Spleen lymphocytes from male Fischer F344 male rats of 5, 13, 22, and 30 months of age were stimulated with either concanavalin A (Con A) or A23187. A 50% decrease in Con A- and A23187-induced proliferation was observed between 5 months and 13 months of age. A23187-induced proliferation decreased only slightly between 13 months and 30 months of age (14%), while Con A-induced proliferation decreased by 34%. This is the first report to show that the induction of lymphocyte proliferation through an interleukin-independent pathway decreases with increasing age. In addition, these results suggest that a decrease in the responsiveness of cells to calcium ions might be an important factor in the age-related decline in lymphocyte proliferation.