Effect of tumour necrosis factor, heat, and radiation on the viability and microfilament organization in cultured endothelial cells

Normal blood vessels are leakage proof, non-adherent to blood cell elements, and participate actively in directional blood flow. These properties rely on the shape of endothelial cells and the integrity of the endothelial cell monolayer. The often observed effects of tumour necrosis factor-alpha (TNF) and hyperthermia on tumour tissue are the disruption of blood flow and an increase of vascular permeability. These agents are also known to affect the cytoskeletal organization and the cytoskeleton-dependent cellular functions. We observed that TNF (100 U/ml for 60 min) or heat (43 degrees C for 60 min) treatment causes the collapse of actin filaments in human umbilical vein endothelial cells (HUVEC). The combined treatment of TNF and hyperthermia intensifies the change of shape and loss of actin filaments. However, these changes are reversible within 24 h. These transient changes may contribute to the dysfunction and increased leakage of the microvasculature in tumours during and after these treatments despite the fact that the viability determined by MTT assay did not show a significant interaction between TNF and hyperthermia. Radiation (5 Gy) and TNF interact to a lesser extent compared with heat and TNF on cell shape and actin filament organization in HUVEC. Heat or radiation treatment enhances the expression of ELAM-1 mRNA in HUVEC while TNF produces the strongest effect on ELAM-1 mRNA expression. Our study suggests that radiation and heat affect endothelial cells and their subsequent functions differently. Result of an interaction between heat and TNF on endothelial cells supports the common notion that the anti-tumour effect by heat plus TNF treatments may benefit due to the increased disruption of vasculature function in the tumour.

Correlation of neuronal cell body size in motor cortex and hippocampus with body height, body weight, and axonal length

This study examined the comparative effects of body height and body weight on the neuronal cell size in humans and investigated their possible mechanisms. A total of 21 cases between the ages of 20 and 40 years were studied. Data on body height, body weight, and neuropathology were obtained from autopsy records. Mean cross sectional areas of cell bodies for 30 normal neurons were determined for the motor cortex projecting to lumbar spinal cord segments (L) 1-4 (Betz cells) as well as various regions of the hippocampus. Approximate axonal length of the motor neuron studied was measured from motor cortex to L2. We found that only motor cortex neuronal cell body size was significantly proportional to body height and the respective axonal length (p < .05). The findings indicate that: 1) body height has a greater effect than body weight on the motor neuron cell size, probably because of its association with axonal length; 2) the effect is regional (motor cortex) rather than general.

Molecular cloning of rat prostate transglutaminase complementary DNA. The major androgen-regulated protein DP1 of rat dorsal prostate and coagulating gland

Complementary DNA (cDNA) that codes for a major androgen-dependent secretory protein of rat coagulating gland and dorsal prostate, dorsal protein 1 (DP1), was isolated by molecular cloning. Recombinant DP1 cDNA clones were identified from a bacteriophage lambda gt11 rat coagulating gland expression library using an affinity purified polyclonal antibody. Amino acid sequence deduced from DNA contained sequences identical with several DP1 cyanogen bromide cleavage fragments. Northern blot hybridization of poly(A) RNA isolated from intact rat dorsal prostate and coagulating gland revealed a predominant messenger RNA (mRNA) species of approximately 3200 nucleotides. Tissue-specific expression of DP1 mRNA was indicated by the absence of DP1 mRNA in ventral prostate and other tissues of the rat. Expression of DP1 mRNA was androgen-dependent, decreasing approximately 80% 7 days after castration and increasing rapidly following androgen replacement. Southern blot analysis of restriction enzyme-digested rat DNA indicated that DP1 is encoded by a single gene and that no major genomic rearrangements accounted for its lack of expression in the dorsal prostate-derived rat Dunning tumor. Sequence comparisons revealed that rat prostate DP1 shares sequence identity with Factor XIIIa and tissue transglutaminase, including the active center, GQCWVF, indicating that DP1 is a member of the transglutaminase gene family.

Response elements of the androgen-regulated C3 gene

Intron and 5'-flanking regions of the androgen-regulated C3 subunit gene contain potential cis-acting transcription control sequences including several 15-base pair (bp) partial palindromes resembling response elements for glucocorticoid (GRE) and progesterone (PRE) receptors. Specific DNA binding of the androgen receptor (AR) and androgen-dependent activation of transcription indicate that some of these GRE/PRE-like sequences are capable of functioning as androgen response elements (ARE). A 0.3-kilobase pair (kbp) 5'-flanking fragment including the promoter region contains one such sequence (element A) and a 0.5-kbp region of the first intron contains two sequences (elements B and C). Androgen-dependent enhancement of transcription was assayed by cotransfection of CV1 cells with a rat AR expression vector, pCMVrAR, and C3 genomic fragments or synthetic elements cloned into the reporter vector ptkCAT. Enhancement of chloramphenicol acetyltransferase activity with the 0.5-kbp first intron fragment was 16 +/- 4-fold, while with the 0.3-kbp 5'-flanking fragment no response was detected and element C alone was greater than B or A. Binding of AR in the mobility shift assay correlated with androgen-dependent enhancement of chloramphenicol acetyltransferase activity. The intensity of transcriptional enhancement with the 0.5-kbp intron fragment suggested that other regulatory sequences within this intron region potentiated the ARE activities of elements B and C. ARE activity of the strongest C3 gene response element (C) was similar to that of a potent GRE (element M) of the mouse mammary tumor virus gene.

Normal and degenerating articular cartilage: in vitro correlation of MR imaging and histologic findings

Histologic correlation of the different magnetic resonance (MR) appearances of articular cartilage has not been studied extensively. Therefore, the authors correlated thin (high-resolution) MR sections of articular cartilage with histologic sections. Human cadaver lumbar facet joints were imaged with a 1-mm section thickness and a 4-cm field of view, then sectioned and stained for histologic comparison. MR imaging patterns were identified that correlated with normal cartilage and three histologically different patterns of degeneration.

Effect of lidocaine on the meninges in an experimental animal model

Arachnoiditis has been reported in patients who had received previous epidural injections of anesthetic agents. The purpose of this study was to determine if epidural injections of lidocaine are sufficient to cause arachnoiditis. Four monkeys that received a single epidural injection of lidocaine hydrochloride 1% were compared to four controls that had epidural injections of 0.9% saline. Four dogs that had multiple epidural injections of lidocaine hydrochloride 1% were compared to four controls that had multiple injections of saline. All animals were killed on the eighty-fourth day of the experiment. The dural sac, containing nerve roots and spinal cord, was removed intact from the lumbar spinal canal, fixed, sectioned, stained, and examined microscopically for evidence of arachnoid inflammation and fibrosis. No significant changes were found in the treated animals. Lidocaine hydrochloride 1% injected singly or repeatedly in the epidural space does not appear to be a cause of significant chronic meningeal reaction.

Positive pulse switching in coupled nonlinear Fabry-Perot cavities

It is shown that positive pulse switching is possible in a system of two coupled nonlinear Fabry-Perot cavities. The conditions in which a signal beam can be switched on and off by positive pulses in the steady state regime are described for cavities filled with Kerr media having a long diffusion length.

Hyperthermia enhances the cytotoxic effects of reactive oxygen species to Chinese hamster cells and bovine endothelial cells in vitro

Hyperthermia is under intensive investigation as a treatment for tumors both alone and in combination with other therapeutic agents. Hyperthermia has a profound effect on the function and structural integrity of tumor microvasculature; this has often been cited as a reason for its effectiveness in treatment of tumors. To test the role of hyperthermia in cytotoxic effects of active oxygen species, Chinese hamster, V79, and bovine endothelial cells were treated by the active oxygens, O not equal to 2 and H2O2, generated from the hypoxanthine/purine and xanthine oxidase reactions. It was found that cytotoxicity to V79 cells depends on the concentrations of purine and xanthine oxidase. A high level of cytotoxicity may be initiated in hyperthermia-treated tumors because high xanthine oxidase activity is known to be associated with tumors and endothelial cells, and degradation processes produce high concentrations of xanthine oxidase substrates in tumors. Since the cytotoxic effect can be reduced by the xanthine oxidase inhibitor, allopurinol, and the H2O2 removal enzyme, catalase, the cytotoxic effect in this experimental system is dependent on xanthine oxidase and H2O2. Adding erythrocytes at the same time as purine and xanthine oxidase could also prevent the cytotoxicity. Elevated temperatures stimulated the reaction of purine and xanthine oxidase and resulted in an increased cytotoxic effect. A similar effect is observed in growth inhibition and colony formation in endothelial cells without adding xanthine oxidase.(ABSTRACT TRUNCATED AT 250 WORDS)

Response of erythrocytes to heat in the presence of D2O, glycerol, and anisotonic saline

Mammalian erythrocytes that lack cytoplasmic organelles and a nucleus are a useful model for studying the effect of heat on the cell membrane and cytoskeleton. The effect of heat on the membrane bilayer and cytoskeleton of erythrocytes is remarkably similar to that observed in nucleated cells. Some concentrations of D2O and glycerol can effectively protect erythrocytes from heat-induced damage to the membrane and cytoskeleton. These results are similar to observations in nucleated cells. Heating erythrocytes in some concentrations of anisotonic NaCl solutions reduced damage, an observation that does not apply to enhanced killing of nucleated cells. This difference implies that some components of the cytoplasm or nucleus, or both, may contribute to the enhancement of cytotoxicity of nucleated cells when they are heated in the anisotonic NaCl solution. Incremental heating, dividing a heat treatment into two fractions, and preheating of erythrocytes all modify the effect of heat on erythrocytes slightly, but the results suggest little, if any, development of thermotolerance. The response of chicken erythrocytes is similar to that of mammalian erythrocytes, although higher temperatures are required to produce a heat effect in chicken erythrocytes. These observations suggest that the characteristic differences in heat sensitivity in nucleated and enucleated cells involve components other than the cell membrane.

Canine intervertebral disks: correlation of anatomy and MR imaging

Because the structure, maturation, and degeneration of canine intervertebral disks resemble those of humans, the authors developed a model of acute intervertebral disk degeneration in dogs. Herniated disks of 18 dogs were examined with magnetic resonance (MR) imaging and then sectioned with a freezing microtome. On the basis of their morphologic appearance in the freezing microtome sections, most of the lumbar intervertebral disks could be categorized as one of six types. Each type has characteristic features and a distinctive appearance on MR images. Findings of this study--including decreased signal intensity from the intervertebral disk, altered signal intensity in contiguous bone marrow, bulging of the anulus fibrosus, herniation of the nucleus pulposus, and contrast enhancement after intravenous administration of gadolinium diethylenetriaminepentaacetic acid (DTPA)--resemble observations from human clinical studies. Classification of degenerating disks and identification of MR imaging characteristics of each type may improve the interpretation of MR images and recognition of early disk degeneration in humans.

Age-related changes in the cervical facet joints: studies with cryomicrotomy, MR, and CT

The cervical facet joints of 20 cadavers were studied systematically with MR, CT, cryomicrotomy, and histologic sections to determine the anatomic changes that occur with age. Uniform layers of cartilage and subarticular cortical bone characterize the cervical facet joints in cadavers under 20 years of age. Most adult cervical facet joints have only a discolored or microscopically thin layer of cartilage and have irregularly thickened subarticular cortical bone. The appearance of the cervical facet joints changes significantly with aging.

Effect of repeated injections of chymopapain in the epidural space

Because arachnoiditis occurred in a previous experimental study, the authors performed additional experimental injections of chymopapain in the epidural space. Four monkeys received epidural injections of 100 units of chymopapain in 1.2 mL of saline on days 1, 8, and 16 of the experiment; four control animals received injections of 1.2 mL of 0.9% saline on the same days. Both groups were killed on the 84th day. The dural sac was removed, fixed, sectioned, stained, and examined microscopically. No significant changes were found in the arachnoid, dura, or epidural space of the treated animals. Chymopapain, even if injected repeatedly into the epidural space, does not cause significant scarring in the meninges.

Coupling of orthogonal polarization states in a nonlinear birefringent cavity

We discuss the coupling of orthogonally polarized beams in a nonlinear cavity and show experimentally how this can be used to implement gates or latches in which one polarization state is switched by another. These devices must be reset by interrupting a light beam and thus must dissipate energy to switch down. The possibility of up and down switching with positive pulses only is also discussed.

Age-related changes in the cervical facet joints: studies with cryomicrotomy, MR, and CT

The cervical facet joints of 20 cadavers were studied systematically with MR, CT, cryomicrotomy, and histologic sections to determine the anatomic changes that occur with age. Uniform layers of cartilage and subarticular cortical bone characterize the cervical facet joints in cadavers under 20 years of age. Most adult cervical facet joints have only a discolored or microscopically thin layer of cartilage and have irregularly thickened subarticular cortical bone. The appearance of the cervical facet joints changes significantly with aging.

Evidence that UGA is read as a tryptophan codon rather than as a stop codon by Mycoplasma pneumoniae, Mycoplasma genitalium, and Mycoplasma gallisepticum

Molecular cloning and sequencing showed that Mycoplasma gallisepticum, like Mycoplasma capricolum, contains both tRNA(UCA) and tRNA(CCA) genes, while Mycoplasma pneumoniae and Mycoplasma genitalium each appear to have only a tRNA(UCA) gene. Therefore, these mycoplasma species contain a tRNA with the anticodon UCA that can translate both UGA and UGG codons.

Correlation of computed tomography and postmortem findings of a diffuse astrocytoma: a case report

Diffusely infiltrating astrocytomas often present diagnostic difficulties. We herein correlate the radiologic and postmortem findings of a diffuse astrocytoma and conclude that recognition of abnormal bilateral and fairly symmetric enlargement and increased density of normal structures in CT scans may lead to an antemortem diagnosis of the tumor.

Primary structure and androgen regulation of a 20-kilodalton protein specific to rat ventral prostate

Nuclear and cytosolic forms of a 20-kdalton rat ventral prostate protein were purified and partially sequenced from their N-termini. Isolated nuclei were treated with micrococcal nuclease and extracted in 0.6 M NaCl, and proteins were separated by affinity chromatography on Matrex gel green A, ammonium sulfate fractionation, and fast protein liquid chromatography on Superose 12. The 43 amino acid N-terminal sequence of the nuclear 20-kdalton protein was identical with the cytosolic protein except it lacked 7 N-terminal amino acids present in the cytosolic form. The DNA sequence of a full-length complementary DNA clone isolated from a ventral prostate gt11 library extended the N-terminal sequence of the cytosolic form by an additional nine amino acids from the predicted initiation methionine. The cDNA included the nucleotide sequence for the 43 amino acid N-terminal sequence of the purified 20-kdalton protein and predicted molecular weights of 16,686, 17,521, and 18,650, respectively, for the nuclear, cytoplasmic, and nonprocessed proteins. Northern blot analyses of reproductive tract tissue RNAs using the 20-kdalton protein cDNA as probe revealed a single mRNA species of 0.92 kb detectable only in extracts of rat ventral prostate. Expression of the 0.92-kb mRNA was androgen dependent since the mRNA was undetectable in extracts obtained 4 days after castration and was restored 16 h after restimulation with androgen.

Synergy of chymopapain and diatrizoate studied in an experimental model

The effect of diatrizoate on the chronic toxicity of chymopapain in the epidural space was studied. Chymopapain was injected epidurally into four monkeys; chymopapain plus diatrizoate meglumine, into four. In 3 months, neither group developed significantly more arachnoiditis than a control group of animals that had received epidural injections of physiologic saline. No synergistic effect of chymopapain and diatrizoate on the meninges was detected.

Effect of experimental root sheath compression on dura

The cause of dural scars and nerve root degeneration sometimes associated with herniated nucleus pulposus has not been explained. We studied experimentally the effect on the dura of its compression. Four animals had laminectomy and placement of a bone chip to elevate the left L4 nerve root sheath. As controls, four animals had laminectomy alone. Four weeks later, treated animals had no more arachnoid fibrosis than controls. The study does not support the hypothesis that chronic mechanical compression causes dural fibrosis.

Criteria for classifying normal and degenerated lumbar intervertebral disks

The purpose of this study was to develop criteria for distinguishing normal and degenerated lumbar intervertebral disks. Cryomicrotome sections from and magnetic resonance images of 31 cadavers were reviewed. The immature nucleus pulposus, found up to age 2 years; the transitional nucleus pulposus, found in teenagers; and the adult nucleus pulposus were associated with an intact anulus fibrosus without tears except for small concentric or transverse tears in the periphery of the anulus fibrosus. Discoloration of the nucleus pulposus, diminishing disk height, and diminishing signal intensity were associated consistently with a radial tear of the anulus fibrosus. The severely degenerated nucleus pulposus was associated also with a radial tear or complete disruption of the anulus fibrosus. The results suggest that intervertebral disk normally progresses from the immature to the transitional to the adult nucleus pulposus. When a radial tear develops in the anulus there is shrinkage and disorganization of fibrocartilage in the nucleus pulposus and replacement of the disk by dense fibrous tissue and cystic spaces.

Fibrous structure in the intervertebral disk: correlation of MR appearance with anatomic sections

To correlate the MR appearance of the disk with its fibrous structure, we studied the lumbar intervertebral disks in 10 cadavers with MR, CT, cryomicrotome anatomic sections, and, in selected disks, with histologic and dried sections. In MR images the predominantly fibrous tissues such as Sharpey's fibers had a low signal intensity while the fibrocartilagenous tissues with a mucoid matrix in the intervertebral disk had a high signal intensity. In the equator of the adult disk was a well-defined fibrous plate that contained collagenous, elastic, and reticular fibers with little ground substance. This plate appeared to develop progressively from the periphery of the nucleus toward the center, starting in the second decade of life. The fibrous plate was also distinguished as a lower signal intensity in the MR images.

An experimental model to study contrast enhancement in MR imaging of the intervertebral disk

MR imaging after IV gadolinium-DTPA administration has demonstrated contrast enhancement in traumatized lumbar intervertebral disks. To characterize the morbid anatomy that correlates with the contrast enhancement, we developed a canine model of traumatized intervertebral disks. Diskectomy was performed with a nucleotome and the spines were imaged biweekly with MR and Gd-DTPA. The spines were studied at necropsy, and their anatomic abnormalities correlated with contrast enhancement detected by MR imaging. Our preliminary results indicate that contrast enhancement occurs where granulation tissue develops in traumatized intervertebral disks.

Effect of chymopapain on the meninges studied in an experimental model

The effect of chymopapain and contrast media in the epidural space on meninges has not been studied conclusively. The authors injected chymopapain into the epidural space of monkeys and measured the degree of arachnoid fibrosis that resulted. Animals were given injections of 1.2 mL of diatrizoate (280 mg iodine per milliliter), chymopapain (100 IU/mL), kaolin (100 mg/mL) (as a positive control), or saline (0.9%) (as a negative control). Three months later the animals were killed; the dural sac was removed intact and was fixed, sectioned, stained, and examined with light microscopy. Kaolin-treated animals developed mild to marked fibrosis of the dura. The saline- and diatrizoate-treated animals developed little or no evidence of fibrosis. One of four chymopapain-treated animals developed degenerative changes in dorsal nerve roots and fibrosis in the adjacent arachnoid. The other chymopapain-treated animals had little or no evidence of fibrosis. The studies suggest that neither diatrizoate nor chymopapain causes arachnoid fibrosis.

Progressive and regressive changes in the nucleus pulposus. Part II. The adult

The spines of 28 cadavers were studied with magnetic resonance (MR) imaging, correlated with anatomic sections, to characterize the progressive and regressive changes in the nucleus pulposus. Four additional types of nucleus pulposus were identified in this study. The transitional type (type II) of childhood had fibrous tissue that developed near the anulus fibrosus anteriorly or posteriorly. MR images showed a notch of reduced signal intensity in the nucleus pulposus where the fiber was developing. The adult type (type III), which is predominant after age 30 years, had an indistinct boundary between the nucleus pulposus and anulus fibrosus. MR images showed the fibrocartilage in the nucleus pulposus and inner anulus fibrosus as areas of high signal intensity. Adult disks with a tear of the anulus fibrosus (type IIIB) had a lower signal intensity on MR images and slightly reduced disk heights. This type may represent an early stage of degeneration. Degenerated intervertebral disks (type IV) had either dense disorganized fibrous tissue or fluid replacing the normal fibrocartilaginous structure of the nucleus pulposus. MR images showed narrow intervertebral disk spaces with either reduced signal intensity if collagen was present or increased signal intensity if fluid was present. This study suggests that the nucleus pulposus may progress normally through types I, II, and III.

Progressive and regressive changes in the nucleus pulposus. Part I. The neonate

Magnetic resonance (MR) imaging, correlated with anatomic sections, was used to characterize the progressive and regressive changes in the nucleus pulposus in neonates. The spines of five fetuses and five full-term infants between 16 and 40 weeks old were studied. In anatomic sections, the nucleus pulposus was sharply demarcated from the anulus fibrosus, Sharpey fibers were conspicuous, and a plate of primitive notochord was evident in the equator of the disk. On long repetition time (TR)/long echo time (TE) or long TR/short TE MR images, Sharpey fibers (low signal intensity) and notochord (low signal intensity) could be differentiated from the high-signal-intensity nucleus pulposus and anulus fibrosus. The major differences between the fetal and infant spines were the amount of notochord in the disk and ossification in the vertebral body.

Ligamentum flavum: appearance on sagittal and coronal MR images

The appearance of the ligamentum flavum on sagittal and coronal magnetic resonance (MR) images has not been described in detail in the radiologic literature. The authors reviewed correlative MR images and anatomic sections obtained with a cryomicrotome in 20 cadavers in order to analyze anatomic relationships, variations, and progressive degenerative changes of the ligamentum flavum in the lumbar region. MR imaging showed the ligamentum flavum as an intermediate-signal-intensity structure on images obtained with short and long repetition times (TRs). Sagittal short TR images were effective for evaluating relationships between the ligamentum flavum, spinal canal, and nerve roots. Degenerative changes in the ligamentum flavum appeared as changes in shape or thickness of the ligaments on MR images. Calcification and fat infiltration, which were well depicted on anatomic sections, were not visualized on MR images.

Stability of heating temperature on cytotoxicity

Chinese hamster V79 cells were used to test the cytotoxic effect of heat which alternates between high and low temperatures during the treatment period. This type of temperature fluctuation is often encountered in clinical hyperthermia. Two sets of heating protocols were used in the experiments: Temperature alternates (a) between 42 and 43 degrees and (b) between 42 and 44 degrees in cycle with equal total "thermal dose," that is heating temperature X heating time. The effectiveness of these heating protocols expressed in average percentage of cell survival depend on the initial temperature attained and the length of the time of this temperature alternation. If the period of temperature change is short such as every 5 or 10 minutes, the cytotoxicity shows very little difference whether the initial treatment temperature is low or high. However, when the period is longer than 20 minutes, the difference in cell survival between the initial temperature at 42 degrees and at higher temperatures is substantial. Cells obtained from logarithmic or plateau phases of growth yield the same result. The difference is likely resulted from a combination of thermotolerance and step-down heating mechanisms. In addition, the effects of heating temperature fluctuation on cytotoxicity is not altered by a 500 cGy of gamma-ray radiation applied either immediately before or after the heat treatment.

Effect of arachnoiditis on pain threshold

A model for studying the relationship between chronic arachnoiditis and pain sensitivity was developed. Thirty male ICR mice were randomly divided into three groups and the tail-flick test was done using an EMDIE-TF6 apparatus (Emdie Instrument Co., Montpelier, VA). Ten mice were injected intrathecally with 5.0 microL of a kaolin-metrizamide mixture and ten control mice were injected intrathecally with 5.0 microL of an electrolyte solution resembling CSF. A third group, (naive controls) were given no treatment. Six weeks later tail-flick tests were repeated. The kaolin-treated mice had significantly decreased tail-flick latencies (P less than .05) compared with the baseline; the controls had no significant change in tail-flick latency. Histologic examination revealed moderate to severe arachnoiditis in the kaolin-treated animals and no evidence of arachnoid abnormalities in the controls. This study suggests that arachnoiditis may be associated with decreased pain thresholds.

Nucleotide sequence of two 3'-termini of rRNA in the sea urchin Lytechinus variegatus

The 3'-terminus of 26 S rRNA from the sea urchin Lytechinus variegatus has been determined by oligonucleotide fingerprinting, S1 nuclease mapping and terminal nucleotide analysis. There are two species of 26 S rRNA of approximately equal abundance, one 19 nucleotides longer than than other.

Subarachnoid hemorrhage following chymopapain chemonucleolysis. Case report

Subarachnoid hemorrhage is a frequent finding in patients who have incurred neurological complications following chymopapain chemonucleolysis, but the basis for this occurrence remains controversial. The authors report the clinical and postmortem findings in a 42-year-old man who died 5 days after chemonucleolysis at the L4-5 and L5-S1 disc spaces. The predominant histological abnormality was a severe inflammatory arteritis of a medium-sized artery at the upper cervical level with disruption of the vessel wall. The potential causative role of chymopapain in this situation and the correlation of a vascular basis for many of the complications found after inadvertent intrathecal chymopapain injector are discussed.

Craniopharyngioma and "reactive" subependymoma of the third ventricle--a case report

A 42-year-old woman with an 18-year history of suprasellar tumor, treated by repeated radiation therapy and surgery, was found to have both a craniopharyngioma and subependymoma of the third ventricle. The case is unique in that well documented subependymomas have not been reported in this location. Furthermore, only a few cases of subependymoma have been reported to be accompanied by a primary tumor of the central nervous system other than an ependymoma. Potential causative factors for this seemingly reactive subependymoma are briefly discussed.

Automated and routine liquid chromatographic analysis of antiepileptic drugs

We describe an optimized automated liquid chromatographic method for simultaneous measurement of primidone, phenobarbitone, phenytoin, carbamazepine and clonazepam. A Waters Tri-Module automation system is used and it provides direct read-out of results after chromatography. A one-step extraction with ethyl acetate is used to extract the drugs from 100 microL serum samples. We use an isocratic mobile phase and monitor the column effluent at 210 nm. Drug levels as low as 5 mumol/L can be detected. The within-run CV's range from 1.4 to 2.7%, and the between-run CV's range from 5.2 to 6.1%. Analytical recovery is in the range from 94-108%. The method compares favourably with the enzyme multiple immunoassay technique for routine antiepileptic drugs monitoring, in accuracy, efficiency and cost-effectiveness.

Correlation of perinatal brain growth with age, body size, sex, and race

This study compares the weight of the human brain to gestational age and body dimensions. A new formula for calculating the rate of growth is proposed. It consists of a second order polynomial function: Y = A0 + A1X + A2X2, in which Y is brain weight, body weight, height, or body surface area; X is gestational age in weeks and A0, A1, and A2 are statistically estimated coefficients. In utero, the growth rate is most rapid for body weight, followed in decreasing order by brain weight, body surface area, and height. Brain growth is the same for both sexes in black and white races; it accelerates between the 20th and 45th weeks of gestation. The size of the newborn infant brain is directly related to gestational age and body size and is not determined by sex or race.

The diethyldithiocarbamate concentration effects and interactions with other cytotoxic agents on Chinese Hamster cells (V79)

A metal chelator, diethyldithiocarbamate (DDC) perturbs the chromosome condensation processes in dividing cells. The length of the metaphase chromosomes in Chinese hamster cells (V79) treated with 17.2 micrograms/ml of DDC for 2 hr is about half of that in untreated cells. However, concentrations of 1.7 microgram or 172 micrograms/ml DDC apparently do not produce this effect. DDC at 17.2 micrograms/ml also disrupts spindle fibers. Penicillamine, EDTA, EGTA, and diamide show no effect on chromosome condensation. Bleomycin, but not mitomycin and cisplatin, added simultaneously with DDC can prevent the DDC effect on chromosomes. The cytotoxic effect of increasing concentrations of DDC to V79 cells incubated at 37 degrees C exhibits a similar biphasic response. This concentration biphasic toxic effect is not altered when the cells are treated with DDC in combination with radiation, heat, or other cytotoxic drugs. These observations suggest that the different effects of DDC concentrations on chromosome condensation should be considered as one important modification factor for DDC related toxicity.

Nucleotide sequence of the transcription initiation region for rRNA in the sea urchin Lytechinus variegatus

The 1191-bp sequence which includes the 5' end of 18S X rDNA and its adjacent spacer have been determined for a cloned fragment of sea urchin rDNA. The 5' end of 33S precursor rRNA (pre-rRNA) has been located by S1 nuclease mapping and primer extension. Pre-rRNA appears to be initiated at an A, 658 bp upstream from the 5' terminus of 18S rRNA. The first nucleotide of 18S rRNA was also analyzed by S1 nuclease mapping and found to correspond to T in the nontranscribed DNA strand. Comparisons of the transcription initiation region in rDNA and the 5' end of 18S X rDNA with the corresponding regions in other eukaryotes reveal no significant nucleotide sequence homology in the precursor portion while the 5' end of 18S X rDNA is highly conserved.

Modification of membrane function, protein synthesis, and heat killing effect in cultured Chinese hamster cells by glycerol and D2O1

Glycerol and D2O can provide a protective effect to Chinese hamster V79 cells receiving heat treatment. The mechanism for this effect is assumed to be the ability of these agents to stabilize proteins which implies that one of the possible heat-killing mechanisms is the inactivation of a heat-sensitive molecule (protein?). In addition, we observed that heat can alter the membrane permeability rapidly, and glycerol can reduce the initial heat-induced membrane permeability changes (determined by aminoisobutyric acid uptake). Although not as effective as cycloheximide, glycerol and D2O can retard protein synthesis. These two processes can add to the protective effect of stabilizing cellular protein against heat killing. Since glycerol and D2O added during the heat-conditioning period can interfere with the appearance of thermotolerance, the mechanisms for the protective effect of glycerol and D2O are likely to be different from heat-induced thermotolerance. We propose that the heat-sensitive molecule protected by D2O or glycerol may also play a role in the triggering process of the thermotolerance phenomenon. If the conditioning heat treatment is sufficient to affect this molecule but not other cellular targets, thus allowing the cell to survive, thermotolerance may be observed in surviving cells in response to second or continued heat treatment. Depending on the severity of the heat effect, this heat-sensitive molecule may continue to exist after a conditioning heat treatment in medium containing glycerol or D2O, and therefore, the response of the cells to the challenging heat is altered little. This proposed mechanism is capable of explaining several thermotolerance experimental protocols. Since glycerol can also reduce the toxicity of vincristine, microtubule-related protein is probably one of the proteins stabilized by this agent. D2O also probably affects microtubule protein, because the cells heated in medium containing D2O show little topological changes.

Arachnoiditis from myelography and laminectomy in experimental animals

Clinical reports have suggested that myelography and laminectomy may produce more arachnoiditis than myelography alone. The effect of experimental lumbar myelography and laminectomy on arachnoiditis in monkeys was studied. Arachnoiditis was as severe after myelography alone as after myelography and laminectomy. Minimal arachnoiditis was found myelographically and histologically after myelography with metrizamide 300 mg l/ml, and severe arachnoiditis was found after myelography with iophendylate whether or not laminectomy was performed. Laminectomy alone produced insignificant arachnoid changes. Experimental myelography preceding laminectomy did not increase the risk of arachnoiditis.

Epidemiologic methodology as used in China

Seven epidemiological methods commonly used in China are discussed. A communicable disease reporting system is in place but this does not include rheumatic diseases. Death registers include cause of death only in selected pilot study points. Field studies using either mobile clinics or nation-wide treatment and prevention programs are useful for infectious diseases. Disease specific surveys of mortality and prevalence are available for hypertension and tuberculosis. Some case control and efficacy studies are also undertaken. Thirty longterm disease surveillance points have been established throughout China.

Chemodectoma involving the cavernous sinus and semilunar ganglion

This paper reports a case of paraganglioma involving the cavernous sinus and semilunar ganglion. The origin of the tumor cells, from paraganglia in this region, is also discussed. Recognition of paraganglia in this area may aid the clinician and pathologist in the differential diagnosis of tumors in this region.

Effect of blood on arachnoiditis from aqueous myelographic contrast media

Bloody cerebrospinal fluid is thought to increase the risk of arachnoiditis from myelography with iophendylate, but not with aqueous media. An experimental study was undertaken of the effects of metrizamide, iocarmate, and blood, independently and in mixtures, on the production of arachnoid fibrosis. Monkeys exposed to a mixture of iocarmate or metrizamide and blood developed no more significant arachnoid fibrosis than animals exposed to the contrast medium alone. Lumbar puncture with bloody cerebrospinal fluid, although a possible cause of adverse effects, is not a contraindication to proceeding with metrizamide myelography.

The weight of the infratentorial portion of the adult brain and analysis of the infratentorial/whole brain weight ratio

A direct relationship exists between the weights of the infratentorial portion (ITP) of the brain and the whole brain. With aging, the weight of the ITP decreases, but the decrease begins later and is smaller than for the forebrain. With whole brain weights, there are significant differences in the weight of the ITP between sexes and between the races. The weight of the ITP increases slightly with increase in body weight. The infratentorial/whole brain ratio is stable during adult life and does not vary with body dimensions. The ratio increases after age 80 because of the accelerated loss of mass of the forebrain. The ratio is the same for both races, but it is significantly higher for the females than for the males. The difference is best accounted for by an arrest in the growth of the forebrain in the female during adolescence.

Arachnoid response to contrast media: a comparison of iophendylate and metrizamide in experimental animals

Arachnoiditis resulting from administration of intrathecal iophendylate (Pantopaque) was compared with that from metrizamide (Amipaque) in 16 monkeys. Four animals initially underwent metrizamide myelography, eight underwent iophendylate myelography, and four control animals received only cerebrospinal fluid. Twelve weeks later, all 16 animals underwent metrizamide myelography and then histologic studies. Animals receiving iophendylate for the first myelogram differed significantly from the other two groups on inflammation, fibrosis, and myelographic evidence of arachnoiditis. The arachnoiditis produced by iophendylate was more severe than that produced by metrizamide; the iophendylate also produced a more cellular reaction that was qualitatively different from the reaction to metrizamide. This more severe reaction to iophendylate has clinical implications for patients undergoing myelography if the contrast medium is not completely removed from the system after myelography.

Granular-cell pituicytoma associated with multiple endocrine neoplasia type

✓ Granular-cell pituicytomas of the neurohypophysis have a controversial histogenesis and oncological behavior. The occurrence of such a tumor in a patient whose father and daughter had endocrine neoplasms suggests a neuroectodermal origin for these tumors. Although all of the conditions considered in this report are unusual clinical entities, their correlation offers considerations in understanding the importance of genetic factors in tumor development.

Computed tomographic appearance of the bulging annulus

Criteria have not been established for differentiating herniated nucleus pulposus and bulging annulus fibrosus by computed tomography (CT). The CT diagnosis of a bulging annulus was evaluated by correlating the CT and anatomic appearance of cadaver lumbar spines, and by comparing CT and surgical findings in patients undergoing lumbar laminectomy. We found that in anatomically or surgically verified bulging annulus, CT showed generalized extension of the disk margin beyond the vertebral body margins. Therefore, bulging annulus can be distinguished by CT from herniated nucleus, which has a focal, usually posterolateral, protrusion of the disk margin.

Fatal misonidazole-induced encephalopathy: an RTOG case report

A case of fatal encephalopathy following administration of misonidazole (MISO) is reported. Anorexia and dehydration preceded signs of encephalopathy after a cumulative dose of 18 g (11 g/m2) of MISO in five weekly doses. Serum MISO levels four hours after weekly administrations were markedly elevated. Postmortem examination revealed focal cortical neuronal necrosis and hemorrhage with focal demyelination. The possible relationship of dehydration or altered drug metabolism to the development of MISO central nervous system toxicity is noted.