Cerebral blood flow changes during cortical spreading depression are not altered by inhibition of nitric oxide synthesis

CBF increases concomitantly with cortical spreading depression (CSD). We tested the hypothesis that CBF changes during CSD are mediated by nitric oxide (NO). Male Wistar rats (n = 23) were subjected to KCl-induced CSD before and after administration of nitric oxide synthase (NOS) inhibitors N-nitro-L-arginine (L-NNA) or N-nitro-L-arginine methyl ester (L-NAME) and in nontreated animals. CBF, CSD, and mean arterial blood pressure were recorded. Brain NOS activity was measured in vitro in control, L-NNA, and L-NAME-treated rats by the conversion of [3H]arginine to [3H]citrulline. Our data show that the NOS inhibitors did not significantly change regional CBF (rCBF) during CSD, even though cortical NOS activity was profoundly depressed and systemic arterial blood pressure was significantly increased. Our data suggest that rCBF during CSD in rats is not regulated by NO.

[Immunohistochemical study on estrogen receptors in conventionally formalin-fixed, paraffin-embedded tissues of endometrial carcinoma]

Using specific monoclonal antibody to human estrogen receptors (ER), monoclonal antibody H222, with an avidin-biotin-peroxidase complex method, immunohistochemical localization of ER was performed on formalin-fixed, paraffin-embedded tissues of 42 endometrial carcinomas. The paraffin sections were preceded by trypsin treatment to expose antigenic sites. Immunohistochemical evaluation incorporated both the intensity and distribution of staining into a semiquantitative analysis. Specific staining for ER was observed only in the nuclei of epithelial, stromal and malignant cells. No specific cytoplasmic staining was observed in all paraffin sections. ER-positive staining [histologic score (H-score) > or = 75] was found in 23 (54.8%) of 42 samples and the ER H-Score of cancer components was significantly associated with the histological grade of endometrial carcinomas (P < 0.05). The ER-positive patients tended to have a better prognosis than ER-negative ones. Thus, it may be concluded that the treated formalin-fixed, paraffin-embedded tissues are still suitable for detecting ER by the immunohistochemical method, and the ER content of endometrial carcinomas is useful in indicating the differentiation of cancer and in predicting the patient's prognosis.

The effect of hypothermia on transient focal ischemia in rat brain evaluated by diffusion- and perfusion-weighted NMR imaging

The effect of moderate whole-body hypothermia (30 degrees C) on transient middle cerebral artery (MCA) occlusion in the rat was evaluated using diffusion- and perfusion-weighted magnetic resonance imaging. Two hours of transient MCA occlusion was induced by intracarotid insertion of a nylon filament under normothermic (n = 14) and hypothermic (n = 7) conditions. Diffusion- and perfusion-weighted imaging were performed before, during, and after focal ischemia from 30 min up to 7 days. In hypothermic animals, scattered neuronal necrosis was localized to select areas of the caudate putamen and the parietal and insular cortex. In contrast, the normothermic ischemic animals exhibited pan-necrosis and infarct encompassing the damaged area. The diffusion and perfusion data measured from caudate putamen indicate that hypothermia causes a significant reduction in the apparent diffusion coefficient of water (ADCw) and CBF values from normothermic control values (p < 0.01). In both normothermic and hypothermic animals after onset of MCA occlusion, ADCw and CBF values in the core of the ischemic region (striatum) significantly declined from the preischemic and homologous contralateral control ADCw and CBF values (p < 0.05). However, ADCw and CBF in the hypothermic group returned toward control more rapidly than in the normothermic group. These results suggest that the protective effect of hypothermia on ischemic cell damage is reflected in the early return of ADCw during reperfusion and the reduction of ischemic cell damage by hypothermia may be mediated by the improved CBF during acute reperfusion.

Upregulation of neuronal nitric oxide synthase and mRNA, and selective sparing of nitric oxide synthase-containing neurons after focal cerebral ischemia in rat

Nitric oxide synthase-containing neurons are presumed to be resistant to neurodegeneration and neurotoxicity, however this resistance has not been demonstrated after focal cerebral ischemia. We therefore measured the temporal profile of neuronal nitric oxide synthase (NOS-I) mRNA and immunoreactivity and NADPH-diaphorase reactivity over a one week period after permanent middle cerebral artery (MCA) occlusion in 48 male Wistar rats and compared these data to ischemic cell damage as evaluated on hematoxylin and eosin (H & E) stained sections by light microscopy. NOS-I mRNA increased as early as 15 min after MCA occlusion in the ipsilateral striatum and maximal expression of NOS-I was found in the ipsilateral cortex and striatum 1 h after MCA occlusion. The numbers of NOS-I-containing neurons in the ipsilateral cortex and striatum were significantly greater (P < 0.05) than NOS-I-containing neurons in the contralateral hemisphere at 2-48 h after the onset of ischemia. The number of NOS-I-containing neurons peaked at 4 h after MCA occlusion. Neurons exhibited shrinkage or were swollen at 1 to 4 h after MCA occlusion. At 24-48 h after ischemia, neurons in the ischemic lesion appeared to be eosinophilic or ghost like on H & E stained sections. However, some of these neurons retained morphological integrity on the NOS-I immunohistochemical sections. At 168 h after ischemia, all neurons within the lesion appeared necrotic on H & E stained sections; however, scatterred neurons expressed NOS-I and NADPH-diaphorase. The rapid upregulation of NOS-I and mRNA in the ischemic lesion suggests that NOS-I is involved in focal cerebral ischemic injury; the expression of NOS-I by neurons that retain their morphological structure in the area of the infarct suggests that NOS-I-containing neurons are more resistant to the ischemic insult. Our data also indicate a close association of NOS-I immunoreactivity and NADPH-diaphorase reactivity in ischemic brain.

Studies on hyperthermic solidification as a supplement to surgical resection in the treatment of 39 advanced cases of liver cancer

Localized hyperthermic solidification therapy employs a high temperature of around 65 degrees C to induce biological heat effects for the solidification and inactivation of the cells of visceral cancers without affecting the physiological processes of the body or any of the viscera. This technique was used in combination with surgical resection to treat 39 moderately or far advanced cases of liver cancer and quite satisfactory results were obtained. The FHCL-92B localized hyperthermic solidification apparatus, designed and manufactured under the supervision of the authors, was preliminarily put into clinical use and exhibited its efficiency. It is believed that, if the technique of localized hyperthermic solidification is introduced more widely into the field of cancer surgery for internal organs, it will be of benefit to prevent iatrogenic metastases and to promote the efficacy of cancer surgery.

p53-immunoreactive protein and p53 mRNA expression after transient middle cerebral artery occlusion in rats

BACKGROUND AND PURPOSE

We investigated the temporal distribution of the p53-immunoreactive protein in conjunction with cellular damage and the expression of the p53 mRNA after focal cerebral ischemia in rats.

METHODS

Male Wistar rats (n = 66; controls, n = 7) were subjected to 2 hours of middle cerebral artery occlusion and were killed at various times of reperfusion (0.5 to 168 hours) for p53 immunohistochemistry and Northern blot analysis.

RESULTS

A cellular expression of mutant p53-immunoreactive protein was found localized to anatomic sites exhibiting severe neuronal damage. A maximal induction of mutant p53-immunoreactive protein was found at 12 hours after reperfusion and subsequently declined. No wild-type p53 protein expression was detected after ischemia. A time-dependent expression of p53 mRNA was observed in both hemispheres. The peak level of p53 mRNA occurred at 24 hours after reperfusion.

CONCLUSIONS

Our data indicate that the expressions of p53-immunoreactive protein and p53 mRNA are upregulated after transient focal cerebral ischemic insult in rats. The concomitant appearance of p53 and cell damage in ischemic brain suggests that p53 expression may impact cell biological response to an ischemic insult.

Repetitive contractions of the upper esophageal body and sphincter in achalasia

This report describes repetitive contractions in the upper esophageal sphincter (UES) and the repetitive upper esophageal spontaneous contractions (RUESCs) of patients with achalasia and relates this activity to repetitive contractile activity (RCA) recorded in the more distal esophageal body, to intraesophageal pressure (IEP), and to lower esophageal sphincter (LES) pressure. Two hundred and sixteen consecutive esophageal motility studies from 156 achalasia patients with retrospectively assessed. RUESCs were found in 105 patients (67%) and 125 of 216 studies (58%). General features of the RUESC were (1) coincidence with simultaneous repetitive increases in pressure throughout the entire esophageal body; (2) amplitude of pressure increases tended to be higher in the proximal esophagus; (3) RUESC frequency was different than respiration, except for 6 cases where continuous, RUESC and RCA were synchronized with inspiration; and (4) RUESCs were positively associated with increased IEP, and with increased LES pressure (> 40 mmHg). RCA in the esophageal body was uncommon without RUESC. It is concluded that (1) RUESCs are common in achalasia and appear to be closely linked to contractile activity in the upper esophageal body; (2) the close relationship of RUESC and RCA in the esophageal body to increased IEP and elevated LES pressure suggests that esophageal tone is high in these subjects; and (3) these findings indicate a potential mechanisms for localization of some of the clinical symptoms to the retrosternal and suprasternal areas, for the inability to readily belch, and for the development of structural features such as a prominent cricopharyngeal bar.

Neuronal survival is associated with 72-kDa heat shock protein expression after transient middle cerebral artery occlusion in the rat

Induction of the 72-kDa heat shock protein expression is thought to protect neurons against the subsequent effects of ischemia. However, it is not clear whether the induction of 72-kDa heat shock protein expression by an ischemic event improves neuronal survival. To address this question, we outlined the temporal profile of neuronal induction and expression of the 72-kDa heat shock protein in a model of transient focal ischemia in the rat. Fifty two adult Wistar rats were subjected to middle cerebral artery occlusion of 2 h duration. At 0.5, 3, 6, 9, 12, 24, 48, 96 and 168 h after reopening the artery, coronal brain sections were analyzed using both immunohistochemical methods and hematoxylin and eosin staining to determine the topographic and cellular distribution of the 72-kDa heat shock protein, as well as the extent of neuronal damage. Immunoreactivity to the 72-kDa heat shock protein was not detected in neurons that were destined to become necrotic, and were located in the ischemic core of the brain lesions. However, 72-kDa heat shock protein expression was evident in morphologically intact neurons located in the peripheral zone. The earliest neuronal expression of 72-kDa heat shock protein was detected in animals in which the 2 h occlusion of the middle cerebral artery was followed by 6 h recirculation; the intensity of the 72-kDa heat shock protein immunoreactivity peaked at 48 h, and progressively disappeared 7 days after the ischemic reperfusion event.(ABSTRACT TRUNCATED AT 250 WORDS)

Temporal evolution and spatial distribution of the diffusion constant of water in rat brain after transient middle cerebral artery occlusion

The regional distribution and temporal evolution of the diffusion coefficient (Dw) of water in rat brain was measured during and after transient middle cerebral artery (MCA) occlusion. Male Wistar rats (n = 14) were subjected to 2 h of middle cerebral artery occlusion, induced by intracarotid insertion of a filament. Diffusion (n = 14) and perfusion (n = 7) weighted magnetic resonance imaging were performed before, and at various time points after MCA occlusion, ranging from 30 min up to 7 days. Our data demonstrate that the temporal profiles of Dw differ between the severely and the least damaged regions of tissue. In the core of the lesion, where the tissue evolved to necrosis, Dw declined significantly (P < 0.001) within 0.5 h after onset of ischemia, and remained depressed until 24 h after withdrawal of the suture. However, no statistically significant decline in Dw was found in the perifocal regions containing morphologically intact cells. Perfusion MRI qualitatively exhibited a hypoperfusion and reperfusion during, and after 2 h MCA occlusion, respectively. A significant (r > or = 0.71, P < 0.01) correlation was found between delta Dw (the difference in Dw between the ipsilateral ischemic and homologous contralateral control regions) obtained immediately before withdrawal of the suture (2 h of ischemia) and at specific early time points after withdrawal of the suture, and the degree of ischemic cell damage. No significant (P > 0.01) correlation was detected at an early time points of ischemia or at other time points after withdrawal of the suture.(ABSTRACT TRUNCATED AT 250 WORDS)

Cerebral endothelial nitric oxide synthase expression after focal cerebral ischemia in rats

BACKGROUND AND PURPOSE

The purpose of this study was to measure the temporal profile of expression of the endothelial nitric oxide synthase (NOS) in cerebral microvessels after middle cerebral artery occlusion in the rat.

METHODS

Middle cerebral artery occlusion was performed on 24 male Wistar rats by extracranial insertion of a 4-0 nylon monofilament into the internal artery. Three additional rats were used as controls. Animals were killed at 1, 2, 4, 6, 24, 48, 72, and 168 hours after middle cerebral artery occlusion (n = 3 per time point). Rat brains were perfused with buffer, frozen, sectioned, and stained with a monoclonal antibody against endothelial NOS. Adjacent sections were stained with hematoxylin and eosin for evaluation of neuronal damage.

RESULTS

The endothelial NOS in the cerebral vessels was upregulated at 1 hour after induction of ischemia throughout the ischemic region. The induction of the endothelial NOS progressively increased up to 24 hours of ischemia. In the periphery of the area of necrosis in the cortex, a delayed (24-hour) upregulation of the endothelial NOS remained constant throughout the duration of ischemia.

CONCLUSIONS

The rapid and intense differential expression of the endothelial NOS in the core and peripheral areas of the lesion indicates a role for endothelial NOS in ischemic cell damage and suggests that the increased expression of NOS may mediate changes in the cerebral blood flow.

Use of eye muscle antibody measurements to monitor response to plasmapheresis in patients with thyroid-associated ophthalmopathy

We have measured eye muscle antibodies, in immunoblotting, in the serum from five patients with severe ophthalmopathy associated with Graves' hyperthyroidism who underwent plasmapheresis, correlating their levels with clinical features of the eye disorder and response to treatment. Blood taken before each plasma exchange was tested in SDS-polyacrylamide gel electrophoresis and Western blotting for antibodies reactive with pig eye muscle membrane (PEMM) antigens and in a 51Cr release assay for antibodies which are cytotoxic to human eye muscle cells in antibody-dependent cell-mediated cytotoxicity (ADCC). Antibodies reactive with a 64 kDa PEMM antigen were detected in three patients who had eye disease of less than six months duration, but not in the two with more chronic disease. Antibodies against a 95 kDa PEMM antigen were detected in one patient in whom anti-64 kDa antibodies were also demonstrated. All five patients showed significant improvement in their eye disease following plasmapheresis exchange and titres of the anti-64 kDa protein antibody decreased in the three patients with detectable levels before treatment. TSH receptor stimulating antibodies were detected in all five patients before treatment, falling during plasmapheresis in four and becoming undetectable in three by the end of treatment. There was no close correlation between levels of TSH receptor antibodies and titres of anti-64 kDa protein antibodies although both tended to fall during and following plasmapheresis. ADCC tests were negative in all five patients before plasmapheresis but, surprisingly, transiently positive in three following treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

[Immunohistochemical detection of estrogen receptors (ER) in endometrial carcinoma]

Immunohistochemical localization of estrogen receptors (ER) using specific monoclonal antibody to human ER, H222, with ABC methods were performed on frozen sections of 22 endometrial carcinoma specimens. Specific nuclear staining of ER was observed in most epithelial, stromal and malignant cells while specific cytoplasmic staining was not observed. ER positive staining (H-Score > 75) was found in 16 of 22 cases (72.7%), and the H-Score of cancer components was significantly associated with the histological grade of endometrial carcinoma (P < 0.05). The data suggest that ER content of endometrial carcinoma reflects the degree of cancer cell differentiation and may be taken as a guideline for hormone therapy.

Postischemic (1 hour) hypothermia significantly reduces ischemic cell damage in rats subjected to 2 hours of middle cerebral artery occlusion

BACKGROUND AND PURPOSE

We investigated the effect of hypothermia induced 1 hour after transient (2-hour) middle cerebral artery occlusion on the extent of ischemic cell damage in the rat.

METHODS

Middle cerebral artery occlusion was induced extracranially by insertion of a nylon filament into the right internal carotid artery. Two groups of rats were investigated: (1) rats (n = 10) subjected to normothermic (37 degrees C) ischemia and normothermic reperfusion; and (2) rats (n = 10) subjected to normothermic ischemia and 1 hour of normothermic reperfusion followed by 3 hours of hypothermia (30 degrees C). All rats were killed 1 week after the experiment, and brain sections were stained with hematoxylin and eosin for evaluation of ischemic cell damage.

RESULTS

Infarct volume in normothermic rats involved 20.9 +/- 4.6% of the hemisphere, whereas hypothermic rats exhibited a significantly smaller (P < .001) infarct volume of 11.1 +/- 2.7%. The numbers of surviving (or structurally intact) neurons within large sections of the cortex and striatum were significantly greater for hypothermic compared with normothermic rats (P < .01).

CONCLUSIONS

Our data suggest that postischemic induction of hypothermia significantly reduces ischemic cell damage after 2 hours of middle cerebral artery occlusion in the rat, and that an interval of time of at least 1 hour after ischemia exists in which hypothermic intervention is effective in either salvaging or postponing irreversible neuronal injury.

Duration dependent post-ischemic hypothermia alleviates cortical damage after transient middle cerebral artery occlusion in the rat

We investigated the effect of post-ischemic 30 degrees C hypothermia on transient middle cerebral artery (MCA) occlusion in the rat. Male Wistar rats (n = 27) were subjected MCA occlusion for 2 h by inserting a nylon filament into the internal carotid artery. Three groups of animals were studied: 1) normothermic ischemia and normothermic reperfusion (n = 13), 2) normothermic ischemia and 1 h of hypothermic reperfusion (n = 6), 3) normothermic ischemia and 3 h of hypothermic reperfusion (n = 6); monitoring of cerebral temperatures were performed on two additional rats. The animals were sacrificed after one week, and coronal sections were obtained and stained with hematoxylin and eosin (H/E) for histopathological examination and determination of infarct volume. The data indicate that both normothermic reperfusion and 1 h hypothermic reperfusion groups exhibited similar infarct volumes in the cortex and the basal ganglia, respectively (P > 0.1). The 3 h post-ischemic hypothermia group revealed a significant decrease in infarct volume in the cortex compared to the normothermic group (P < 0.05). However, the infarct volume of the basal ganglia was not significantly lessened by the 3 h post-ischemic hypothermia. Thus 3 h post-ischemic hypothermia provides preferential reduction of cell damage in the cortex, from 2 h of MCA occlusion in the rat.

Pathogenesis of thyroid-associated ophthalmopathy: an autoimmune disorder of the eye muscle associated with Graves' hyperthyroidism and Hashimoto's thyroiditis

Thyroid-associated ophthalmopathy, the progressive eye disorder which occurs frequently in patients with Graves' hyperthyroidism and, occasionally, in those with Hashimoto's thyroiditis, may be a two-stage disorder of the eye muscle. In the first stage, which may occur in the great majority of patients with Graves' hyperthyroidism and in an unknown, but probably small, proportion of those with Hashimoto's thyroiditis, antibodies and CD4+ (helper) T lymphocytes reactive with eye muscle and thyroid shared antigens, of which 64-kDa membrane proteins are good candidates, may initiate a mild eye muscle inflammation, manifested as eye muscle swelling on orbital imaging. The second stage, which occurs in about 25% of patients with Graves' hyperthyroidism and in 2% of those with Hashimoto's thyroiditis, may be due to reactivity of cytotoxic antibodies against eye muscle-specific membrane antigens, one of which at approximately 35 kDa appears a likely candidate, and, possibly, cytotoxic T cells in the context of the appropriate class I MHC molecule. Orbital connective tissue inflammation, which plays an important role in the development of progressive orbital inflammation, is likely to be secondary to the eye muscle reaction. The recent cloning of a 64-kDa thyroid and eye muscle antigen which shares significant homology with the muscle protein tropomodulin and mapping of its antibody-reactive epitopes provide structural information about one candidate eye muscle autoantigen and promise for a more rational approach to the diagnosis and management of this common, progressive eye disorder.

Nitric oxide measured by a porphyrinic microsensor in rat brain after transient middle cerebral artery occlusion

We measured, in vivo, the local concentration of nitric oxide (NO) in cerebral tissue, during and after transient middle cerebral artery occlusion in the rat (n = 8). Baseline concentration of NO was < 10(-8) M; upon initiation of ischemia, NO concentration increased to approximately 10(-6) M and then declined. Reperfusion likewise stimulated an increase in NO concentration to above baseline level. Administration of N-nitro-L-arginine methyl ester (n = 4), an inhibitor of nitric oxide synthase, before onset of ischemia, maintained NO at basal levels. Our data indicate that large increases in NO occur at onset of ischemia, which may affect tissue response to an ischemic insult.

Isolation and characterization of a human ileocecal carcinoma cell line (HCT-8) subclone resistant to fluorodeoxyuridine

A 5-fluoro-2'-deoxyuridine (FdUrd)-resistant subclone (Fd9XR) of HCT-8 (human ileocecal carcinoma) cells was established by two schedules of drug exposure. Initially, cells were exposed to short-term (3 hr) 100 nM FdUrd repeatedly (9 cycles over 8 months), and cells were then exposed to 10 nM FdUrd continuously. During this latter stage, a colony (Fd9XR) with fast growth rate was isolated, expanded, and characterized with respect to mechanisms of resistance to FdUrd and cross-resistance to other chemotherapeutic agents. Fd9XR cells were 1000-fold resistant to FdURD, but 3-fold more sensitive to 5-fluorouracil (FUra) than HCT-8 cells. After a 3-hr treatment with FdUrd, Fd9XR cells accumulated 6630-, 69-, and 3.7-fold less fluorodeoxyuridylate (FdUMP), fluorouridine triphosphate (FUTP) and acid-insoluble materials, respectively, than HCT-8 cells. However, when FUra was substituted for FdUrd, Fd9XR cells accumulated 9.2-, 3.1-, and 2.3-fold more FdUMP, FUTP and acid-insoluble materials, respectively, than HCT-8 cells. Fd9XR and HCT-8 were similar in their growth rates, combined pools of 5,10-methylenetetrahydrofolates (5,10-CH2H4PteGlun) and tetrahydrofolates (H4PTeGlun), thymidine phosphorylase (TP) activity, and level and activity of thymidylate synthase (TS). In contrast, thymidine kinase (TK) activity of Fd9XR was 0.23 and 0.35% of that of HCT-8, for thymidine (dThd) and FdUrd as substrates, respectively. Furthermore, Fd9XR cells exhibited greater sensitivity to the antifolate TS inhibitor ICI D1694 and to methotrexate (MTX) than HCT-8 cells. In addition, dThd alone and in combination with hypoxanthine did not offer any protection against the cytotoxic effect of ICI D1694 in Fd9XR cells. These results indicate that in Fd9XR cells (1) TK deficiency is the primary mechanism of resistance to FdUrd; (2) the greater sensitivity to FUra was associated with higher pools of FdUMP and FUTP with a subsequently higher level of incorporation into cellular RNA; and (3) antifolate compounds, e.g. ICI D1694 and MTX, could be useful agents in the treatment of FdUrd-resistant tumors associated with decreased TK activity and decreased capacity of utilizing dThd.

Progression from ischemic injury to infarct following middle cerebral artery occlusion in the rat

Focal brain ischemia induced in rats by occlusion of an intracranial artery is a widely used paradigm of human brain infarct. Details of the structural changes that develop in either the human or the rat brain at various times after occlusion of an intracranial artery are incompletely characterized. We studied, in 48 adult Wistar rats, structural alterations involving the cerebral hemisphere ipsilateral to an arterial occlusion, at intervals ranging from 30 min to 7 days. Microscopic changes developed over time in separate areas of the corresponding cerebral hemisphere in a predictable pattern, appearing as small lesions in the preoptic area (30 minutes), enlarging to involve the striatum, and finally involving the cerebral cortex. Two types of neuronal responses were noted according to the time elapsed; acute changes (up to 6 hours) included scalloping, shrinkage, and swelling, whereas delayed changes (eosinophilia and karyolysis) appeared later (> or = 12 hours). Three types of astrocytic responses were noted. 1) Cytoplasmic disintegration occurred in the preoptic area at a time and in a place where neurons appeared minimally injured. 2) Nuclear and cytoplasmic swelling were prominent responses in the caudoputamen and cerebral cortex at a time when neurons showed minimal alterations. 3) Increased astrocytic glial fibrillary acidic protein reactivity was noted at the interface between the lesion and the surrounding brain tissue after 4 to 6 hours. The gross pattern of the brain lesion and the maturation of neuronal changes typical of a brain infarct have a predictable progression. Focal brain ischemia of up to 6-hour duration does not induce coagulation necrosis.

[Culture medium for protocorm differentiation in Dendrodium candidum Wall. ex Lindl]

Effects of basal culture medium, sucrose concentration, natural extracts and phytohormones on protocorm differentiation were studied. The suitable medium for protocorm differentiation has been found to be 1/2Ms basal medium plus 2% w/v sucrose, 2mg/L BA, 0.2mg/L NAA and 20% (w/v) potato extract.

Nature of 64 kDa eye muscle and thyroid membrane proteins and their significance in thyroid-associated ophthalmopathy--an hypothesis

Although a variety of eye muscle antigens are recognized by autoantibodies in the serum from patients with thyroid associated ophthalmopathy (TAO) 64 kDa membrane proteins, which are also expressed in the thyroid, are most closely linked to the development of ophthalmopathy in patients with autoimmune thyroid disease. A cloned 64 kDa protein called 1D, which shares homology with tropomodulin, appears to be closely related to a 64 kDa eye muscle protein identified in immunoblotting and both may be members of a family of cytostructural proteins. The relationship between 64 kDa proteins in eye muscle and thyroid, and its equivalent in somatic skeletal muscle, will only be understood when the various proteins are cloned from expression libraries, sequenced and their consensual and unique domains identified. Since these 64 kDa antigens are expressed in both thyroid and eye muscle, a possible mechanism for the association of ophthalmopathy with autoimmune thyroid disease is immunological cross-reactivity by autoantibodies and sensitized T lymphocytes. Autoantibodies reactive with 64 kDa eye muscle proteins are associated with ophthalmopathy in patients with autoimmune thyroid disorders and predictive of the development of ophthalmopathy in patients with Graves' hyperthyroidism.

Time dependence of DNA lesions and growth inhibition by ICI D1694, a new quinazoline antifolate thymidylate synthase inhibitor

DNA single-strand breaks and associated growth inhibition induced by the thymidylate synthase inhibitor N-(5-[N-(3,4-dihydro-2-methyl-4-oxoquinazoline-6-ylmethyl)-N -methylamino]-2 - thenoyl)-L-glutamic acid (ICI D1694) were quantitated using the human ileocecal adenocarcinoma cell line, HCT-8. The effects of different concentrations and schedules of [6R,S]-5-formyltetrahydrofolate ([6RS]LV) and 2'-deoxy-thymidine (dThd) on drug growth inhibition and DNA damage were also evaluated. The drug concentrations for 50% inhibition of cell growth in culture following 2-h and 72-h exposures were 0.073 and 0.003 microM, respectively. After a 2-h drug exposure, the occurrence of DNA single-strand breaks (SSBs) was time dependent. It was detectable at 8 h and reached a maximum at about 24 h, 34 +/- 3 (SD) and 305 +/- 34 rad equivalents with 0.1 microM (50% inhibition concentration) and 1.0 microM (90% inhibition concentration) ICI D1694, respectively. A significant level of DNA SSBs (101 +/- 13 rad equivalents) was still detectable at 72 h after the 2-h treatment with 1 microM ICI D1694. No significant level of DNA SSBs was detected when cells were exposed simultaneously to ICI D1694 and 20 microM [6RS]LV. Complete rescue of drug-induced DNA SSBs could be achieved when cells were exposed to 10 microM dThd starting no later than 4 h after drug treatment. The growth inhibition of ICI D1694 was abrogated by [6RS]LV in a concentration-dependent manner. Complete protection was achieved when cells were exposed simultaneously to 1 microM ICI D1694 and 5 microMs [6RS]LV or to 3 microMs dThd immediately after drug treatment. The results demonstrate that: (a) the growth inhibition of ICI D1694 is a function of time and schedule; (b) the growth inhibition is accompanied by extensive DNA single-strand breaks and slow repair; (c) at 1 microM ICI D1694, 3 microMs dThd and 5 microMs [6RS]LV can completely rescue cells from drug effects when dThd is added up to 4 h following drug treatment or when [6RS]LV is given in combination with the drug; (d) interference of [6RS]LV with ICI D1694 action may be occurring at the level of drug uptake and at intracellular targets, while dThd interferes with the drug action at intracellular targets.

Distribution of the 72-kd heat-shock protein as a function of transient focal cerebral ischemia in rats

BACKGROUND AND PURPOSE

The significance and physiological implications of the expression of the 72-kd heat-shock protein in ischemic tissue are unknown. To enhance our understanding of the relation between ischemic cell damage and 72-kd heat-shock protein expression, we evaluated the cellular expression and the anatomic distribution of 72-kd heat-shock protein in conjunction with the morphological analysis of rat brain, as a function of the duration of a single arterial occlusion.

METHODS

Adult Wistar rats were subjected to graded transient middle cerebral artery occlusion (for a duration of 10, 20, 30, 60, 90, and 120 minutes and sham; n = 4 per group). Forty-eight hours after reopening the artery, brain tissue sections were analyzed to determine the extent of neuronal damage (hematoxylin and eosin staining), the extent of astrocytic reactivity (immunohistochemistry, using anti-glial fibrillary acidic protein), and the distribution of 72-kd heat-shock protein (immunohistochemistry, using a monoclonal antibody to 72-kd heat-shock protein).

RESULTS

We found that 72-kd heat-shock protein was sequentially expressed in morphologically intact neurons, microglia, and endothelial cells with increasing duration of ischemia; 72-kd heat-shock protein immunoreactivity was not detected in astrocytes. The duration of ischemia required to evoke a 72-kd heat-shock protein response in neurons was dependent on the anatomic site and followed a pattern of increasing neuronal sensitivity to ischemic cell damage with duration of ischemia: 72-kd heat-shock protein and neuronal damage were sequentially detected in the caudate putamen, globus pallidus, cerebral cortex, amygdala, and hippocampus with increasing duration of ischemia. With ischemia of long duration (greater than or equal to 90 minutes), neurons expressing 72-kd heat-shock protein were localized to a zone peripheral to the severely damaged ischemic core.

CONCLUSIONS

These studies suggest that 1) the expression of 72-kd heat-shock protein in neurons precedes the development of ischemic cellular alterations detectable by conventional hematoxylin and eosin light microscopy methods; 2) there is a hierarchy of cell types and anatomic sites that express 72-kd heat-shock protein, and this hierarchy reflects cellular and anatomic vulnerability to ischemic cell damage; and 3) 72-kd heat-shock protein induction in neurons bordering a necrotic ischemic core may be the morphological equivalent of the ischemic penumbra.

The effect of hypothermia on transient middle cerebral artery occlusion in the rat

We investigated the effect of moderate whole body hypothermia (30 degrees C) on transient middle cerebral artery occlusion (MCAO) in the rat. Male Wistar rats were subjected to 2 h of ischemia by inserting a suture into the lumen of the internal carotid artery and occluding the origin of the MCA. Experimental groups were (a) MCAO induced at 37 degrees C body temperature (n = 15); (b) 30 degrees C body temperature induced prior to ischemia and maintained for 2 h of MCAO and 1 h of reperfusion (n = 12); and (c) MCAO with regional brain and body temperatures measured in normothermic (n = 3) and hypothermic MCAO rats (n = 2). Histopathological evaluation was performed 96 h after reperfusion. All normothermic MCAO animals exhibited ischemic infarct involving the ipsilateral cortex and basal ganglia with infiltration of neutrophils, macrophages, and microvascular proliferation. Hypothermic MCAO animals exhibited minor ischemic damage ranging from selective neuronal injury to small focal areas of infarct with minimal inflammatory response. Our data demonstrate that transient ischemia induced by using the intra-arterial suture method to occlude the MCA results in a reproducible brain lesion and that moderate hypothermia has a profound protective effect on the brain injury after transient MCAO.

Mechanisms of resistance to fluoropyrimidines

The fluoropyrimidines fluorouracil (5-FU) and 5-fluoro-2'-deoxyuridine (FdUrd) have shown activity in a variety of malignancies. Nevertheless, even in initially responsive tumors, the development of resistance is a frequent problem. To understand the biochemical basis for acquired resistance, two pairs of cell lines were investigated. MCF7/Adr cells were obtained from the breast cancer cell line MCF7 by incubation with increasing concentrations of Adriamycin (doxorubicin; Adria Laboratories, Columbus, OH). These cells are resistant to Adriamycin (200- to 600-fold) and cross-resistant to 5-FU (25-fold) and FdUrd (67-fold). The resistant cells showed significantly increased levels of thymidylate synthase, the target enzyme of the fluoropyrimidines' active metabolite, 5-fluoro-2'-deoxyuridine-5'-monophosphate (FdUMP). Other biochemical characteristics, including folate pools, drug uptake, metabolism, and retention, were unchanged. Fd9XR cells have been selected from a human colon cancer cell line (HCT-8) by exposure to FdUrd. These cells are resistant to FdUrd (1,000-fold) but not 5-FU. Biochemical evaluations show that the resistant cells are deficient of thymidine kinase and are thus unable to convert FdUrd to FdUMP. This understanding of the various biochemical mechanisms is essential for the design of specific modulations to overcome resistance to fluoropyrimidines.

Modulation of fluoropyrimidines: role of dose and schedule of leucovorin administration

The biochemical modulation of 5-fluorouracil (5-FU) and 5-fluoro-2'-deoxyuridine (FdUrd) by leucovorin (LV) has resulted in a significant improvement of the antitumor activity in a variety of malignancies. Although this combination is frequently used, the optimal dose and schedule of LV remains to be determined. In vitro studies with human colon carcinoma (HCT-8) and renal carcinoma (SE) cells show that the increase of intracellular folate pools by LV is dose and time dependent and varies significantly between cell lines. While HCT-8 cells showed optimal modulation of FdUrd cytotoxicity with 1 mumol/L [6S]LV for 5 hours, SE cells required 10 mumol/L [6S]LV for 5 days. Clinical data indicate that low doses of [6R,S]LV (20 mg/m2) might be equivalent to higher doses (200 to 500 mg/m2) when 5-FU is given on 5 consecutive days, whereas doses of 200 mg/m2 might be necessary when 5-FU chemotherapy is given once weekly. Unless biochemical assays to assess a patient's individual needs of LV become available, the use of higher (200 to 500 mg/m2) doses might offer the best chance to effectively modulate 5-FU clinically.

Pharmacologic rationale for fluoropyrimidine-leucovorin combination: biochemical mechanisms

Fluoropyrimidines, 5-fluorouracil (5-FU), and 5-fluorodeoxyuridine (FdUrd) are effective inhibitors of DNA synthesis. Inhibitory action is potentiated both in vitro and in vivo by the addition of leucovorin (LV; either the natural [6S] isomer or the mixture of the unnatural and natural [6R,S] isomers). The inhibition of DNA is subsequent to thymidylate synthase inhibition mediated by the formation of a covalently bound ternary complex consisting of 5-fluorodeoxyuridine monophosphate, 5,10-methylenetetrahydrofolate, and thymidylate synthase. In vitro exposure of cells to varying concentrations of [6R,S]LV or [6S]LV increases intracellular pools of the reduced folate cofactor. The effect of [6S]LV is both dose and time dependent. The in vitro effective concentration of [6S]LV is approximately 1 to 10 mumol/L, depending on cell type. While HCT-8 cells demonstrated optimal modulation of 5-FU and FdUrd cytotoxicity with 1 mumol/L of [6S]LV for 5 hours, the SE cells required higher doses of LV and longer exposure time. Thus, dependent on the cell type, higher concentration (10 mumol/L) and duration of exposure (greater than 5 hours) may be essential for an effective modulation of fluoropyrimidine action. Clinically, to achieve the concentration and conditions found optimal in an in vitro system, a dose of 500 mg/m2 by 5-hour infusion appears to be the present optimal dose and schedule of [6R,S]LV administration in combination with 5-FU.

p53 expression in brain after middle cerebral artery occlusion in the rat

The purpose of this study is to determine whether the p53 protein, a product of the p53 tumor suppressor gene, that has been associated with the 72 kDa heat shock protein (hsp72), is expressed in ischemic brain. Adult Wistar rats (n = 5) were subjected to 120 minutes of middle cerebral artery occlusion. Twelve hours after reopening the artery, brain tissue was analyzed to determine the extent of neuronal damage (hematoxylin and eosin), and the distribution of p53 and hsp72 (monoclonal antibodies). Our data demonstrate that p53 is expressed in regions of neuronal necrosis; in contrast, morphologically intact neurons express hsp72. The data suggest that the presence of p53 is associated with cell death and that hsp72 may regulate p53 function.

Restricted tissue reactivity of autoantibodies to a 64-kDa eye muscle membrane antigen in thyroid-associated ophthalmopathy

We studied the tissue specificity of eye muscle (EM) membrane-reactive autoantibodies detected in the serum of patients with thyroid-associated ophthalmopathy (TAO). In preliminary studies, such antibodies were shown to react, in sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blotting, with human thyroid (THY) and other human skeletal muscle (HSM) membrane antigens. We carried out absorption with human EM (HEM), THY, and HSM membranes of sera from patients with TAO and autoimmune thyroid disease without ophthalmopathy which reacted with one or more of 55-, 64-, and 95-kDa antigens in pig eye muscle (PEM) membrane in immunoblotting, the majority of which were also cytotoxic to HEM cells in an antibody-dependent cell-mediated cytotoxicity assay. In Western blotting, serum antibodies reactive with PEM membrane antigens of 55, 64, and 95 kDa were cross-absorbed by HEM, THY, and HSM but not by spleen or brain membranes and showed some species specificity, being absorbed by pig and human, but not bovine, EM membranes. When incubated with cultured HEM, THY, and HSM cells in vitro, autoantibodies in TAO sera immunoprecipitated a 64-kDa antigen from the first two tissues, but not from HSM, suggesting a specific binding to autoantigenic epitopes in HEM and THY. Sera from patients with TAO as well as those from patients with thyroid autoimmunity without ophthalmopathy immunoprecipitated a approximately 66-kDa protein, shown to be distinct from the 64-kDa antigen. The restricted immunological cross-reactivity of antibodies to a THY and HEM 64-kDa membrane antigen is discussed in the context of the association of ophthalmopathy with thyroid autoimmunity. Further experiments are needed to show whether autoantibodies to the 64-kDa eye muscle and thyroid shared antigen are cytotoxic, and thus likely to play a major role in the pathogenesis of the eye disease, or just markers of the orbital autoimmune process.

Antibodies in the serum of patients with autoimmune thyroid disorders react with a recombinant 98 amino acid fragment of a full length 64 kDa eye muscle membrane protein which is also expressed in the thyroid

We have tested sera from patients with autoimmune thyroid disorders with or without ophthalmopathy for immunoreactivity, in a dot blot assay, against a recombinant 98 amino acid fragment of a cloned 64 kDa protein, D1, which is expressed in human eye muscle and thyroid, in the form of a Lac Z fusion protein. Tests were positive in 19 out of 40 patients with established thyroid-associated ophthalmopathy (TAO), in 12 out of 21 patients with Graves' hyperthyroidism (GH) without clinically evident ophthalmopathy, in 5 out of 10 patients with thyroid autoimmunity and lid retraction but no other signs of ophthalmopathy, in 4 out of 23 patients with Hashimoto's thyroiditis (HT) without evident ophthalmopathy and in 2 out of 18 patients with benign adenoma or multinodular goitre, but in only 2 out of 37 normal subjects tested. SDS-polyacrylamide gel electrophoresis and Western blotting for an antibody reactive with a 64 kDa antigen in pig eye muscle membranes was also carried out on sera from patients with TAO and GH. While immunoblotting for antibodies reactive with a 64 kDa protein was more often positive in patients with TAO, in whom 58% had serum antibodies which reacted with a 64 kDa protein, this was not the case in patients with GH without eye signs in whom the prevalence of positive immunoblot tests was 35%. Overall there was a fairly close correlation between the two tests although there were many exceptions.(ABSTRACT TRUNCATED AT 250 WORDS)

Nature and significance of orbital autoantigens and their corresponding autoantibodies in thyroid-associated ophthalmopathy

There is now considerable evidence that the pathogenesis of thyroid-associated ophthalmopathy is closely linked to the presence of a shared autoantigen(s) in the thyroid and the eye muscle, against which cytotoxic mechanisms are directed. Although the orbital connective tissue is certainly involved in the orbital inflammatory process, a 64 kDa membrane protein expressed by both the eye muscle and the thyroid and recognized consistently by antibodies in the sera of TAO patients, seems to be the most likely target candidate. While its presence in non ocular skeletal muscle is not as well established, more recent data tend to suggest the existence of a 64 kDa molecule in the three tissues. The availability of a cDNA encoding a 572 amino acid protein corresponding to a MW of 63-64 kDa, which may be the same molecule, will allow us to determine more clearly the structural characteristics of the different molecules proposed as targets. The role of the corresponding autoantibodies in the pathogenesis of the eye disease is far less well defined. Whether they play a role in the induction of the ophthalmopathy or only represent helpful markers remains to be clarified.

Endotracheal administration of epinephrine during cardiopulmonary resuscitation

A hypoxia-induced canine cardiac model was used to study the effectiveness hemodynamic response, arterial blood gas and pulmonary pathologic changes after endotracheal (ET) epinephrine administration in comparison with those from intravenous (IV) administration. The results indicated that the survival rate was the same with the drug given by either route. The increase of hemodynamic indices was lower in the group after ET administration than that after IV administration. No significant influence was exerted on the drug effects whether the drug is diluted in normal saline or in distilled water and no serious detrimental effects occurred on the lung tissues following ET epinephrine administration.

Analysis of eye lens-specific genes in congenital hereditary cataracts and microphthalmia of the miniature schnauzer dog

The congenital hereditary cataracts and microphthalmia in the miniature schnauzer dog are inherited by an autosomal recessive mode. To understand the genetic basis of these diseases, the authors purified and analyzed leukocyte deoxyribonucleic acid (DNA) from affected and normal animals using a candidate gene approach. Because the genes that encode the lens-specific proteins, specifically, alpha, beta, and gamma crystallins and the membrane protein (MP26), are known to maintain the structure and function of the lens, the authors used complimentary DNA (cDNA) fragments that corresponded to the above genes to search for the mutations at their loci in the affected animals. They found no evidence of the gene deletion and rearrangement in any of the five loci. In addition, the hybridizable sequences of the dog DNA to the specific probes for the human chromosome 4 and 18 loci, which are reported to be involved in the abnormality of the human eye, seem to be unaffected. These data support the notion that the hereditary cataracts and microphthalmia in the dog may be associated with genes other than those reported for several animal systems.

Effects of diastereoisomers of 5-formyltetrahydrofolate on cellular growth, sensitivity to 5-fluoro-2'-deoxyuridine, and methylenetetrahydrofolate polyglutamate levels in HCT-8 cells

We investigated the biological activities of the natural and unnatural diastereoisomers of 5-formyltetrahydrofolate [(6S)- and (6R)-5-HCO-H4PteGlu, respectively, both 99.99% pure], using a human ileocecal carcinoma cell line (HCT-8). Optimal cell growth could be supported by (6S)-5-HCO-H4PteGlu at concentrations as low as 1 nM. (6R)-5-HCO-H4PteGlu did not support growth. Modulation of the in vitro cytotoxicity of 5-fluoro-2'-deoxyuridine (FdUrd) and intracellular (6R)-5,10-methylenetetrahydrofolates [(6R)-CH2H4PteGlun] pools by (6S)- and (6R)-5-HCO-H4PteGlu was determined with cells growing in 1 nM (6S)-5-HCO-H4PteGlu. For the control cells, the concentration of FdUrd inhibiting growth by 50% was 179 nM and the total (6R)-CH2H4PteGlun was 2.3 pmol/10(6) cells. When cells were treated with (6S)-5-HCO-H4PteGlu for 24 h, the 50% inhibition concentration of FdUrd decreased with increasing concentrations of (6S)-5-HCO-H4PteGlu, and reached a plateau of 36 nM when (6S)-5-HCO-H4PteGlu was greater than or equal to 1 microM. The total (6R)-CH2H4PteGlun pools were augmented by (6S)-5-HCO-H4PteGlu dose dependently up to 6.8 pmol/10(6) cells at 1 microM (6S)-5-HCO-H4PteGlu. (6S)-5-HCO-H4PteGlu at 10 microM did not further increase the total (6R)-CH2H4PteGlun, but induced a marked shift in the polyglutamate chain length distribution, with an increase in tri- and tetra-, and a decrease in penta-, hexa-, and heptaglutamate. The down-shift of (6R)-CH2H4-PteGlun polyglutamate chain length observed after (6S)-5-HCO-H4PteGlu treatment did not impair the modulation of FdUrd cytotoxicity. Thus shorter chain (6R)-CH2H4PteGlua (n = 3-4) function as well as longer ones (n = 5-7). (6R)-5-HCO-H4PteGlu, at 200 microM, had no effect on the cytotoxicity of FdUrd, the total (6R)-CH2H4PteGlun level, or chain length distribution in the presence or absence of additional (6S)-5-HCO-H4PteGlu. These results suggest that the high plasma (6R)-5-HCO-H4PteGlu concentrations (up to 200 microM) achieved in patients following i.v. administration of high doses of (6R,S)-5-HCO-H4PteGlu probably do not have adverse effects on the modulation of antitumor activity of FdUrd or 5-fluorouracil. Since the optimal dose and schedule of (6S)-5-HCO-H4PteGlu for modulation of fluoropyrimidines may vary from one cell type to another, introducing high doses of (6R,S)-5-HCO-H4PteGlu in patients so that the plasma concentration of the natural isomer reaches 10 microM is still recommended.

Muscle and species reactivity of mouse monoclonal antibodies to human eye muscle membrane antigens

We studied the tissue and species reactivity of mouse monoclonal antibodies (MCAB) produced by immunizing mice with a 100,000g ultracentrifuged preparation of human eye muscle (HEM) membranes. Twenty-three MCABs, 20 of which reacted in an enzyme-linked immunosorbent assay (ELISA) with HEM membrane, 2 with human thyroid membrane, and 1 nonreactive negative control, were selected for the study. The muscle and species specificity of 6 of the most reactive and more restrictively reactive MCAB were studied in more detail. All reacted in ELISA with human skeletal muscle membrane and, to a lesser extent, with human cardiac muscle membrane, but not with human brain membrane. The 6 MCAB cross-reacted with eye muscle membrane prepared from pig but not rat, although reactivity with human tissue was greatest for all MCAB tested. When tested in immunoblotting with HEM and thyroid membranes, 3 of 6 MCAB reacted with a 64-kDa protein in HEM, 2 of which also reacted with an antigen of the same molecular weight in thyroid membrane. In a complement-mediated antibody-dependent cytotoxicity assay, 5 of 19 MCAB lysed HEM cells, 6 of 21 lysed human skeletal muscle cells, and 10 of 22 lysed human thyroid cells. These findings support results from earlier clinical studies which showed that eye muscle membrane reactive autoantibodies in the serum of patients with thyroid-associated ophthalmopathy cross-react with membrane prepared from other striated muscle. The significance of eye muscle, skeletal muscle, and thyroid cross-reactivity of MCAB is discussed in the context of autoimmune thyroid disease and ophthalmopathy.

Xenopus transcription factor IIIC (TFIIIC) specifically interacts with the "B" block region of the TFIIIA gene

Transcription factors IIIC (TFIIIC), TFIIIB and RNA polymerase III are commonly required for class III gene transcription in vitro. To understand the diversity and specificity of Xenopus TFIIIC, we have further characterized this factor. Our analyses indicate that a partially purified TFIIIC fraction contains an activity which specifically recognizes the "B" block element of TFIIIA gene. Stable complex formation assays with HeLa cell extracts demonstrate that the TFIIIA gene can stably sequester TFIIIC. off

Prevalence of antibodies reactive with a 64 kDa eye muscle membrane antigen in thyroid-associated ophthalmopathy

We have determined the prevalences of antibodies reactive with certain pig eye muscle membrane antigens, as determined from SDS-polyacrylamide gel electrophoresis (PAGE) and western blotting, in patients with autoimmune thyroid disorders with or without associated ophthalmopathy. The most frequently detected antibody was that directed against a protein of 64 kDa. Antibodies against this antigen were detected in 33% of unselected patients with ophthalmopathy and in 75% of those with severe, active, orbital inflammation of less than 12 months duration. Such antibodies were detected also in 33% of patients with Graves' hyperthyroidism with no apparent eye disease and in 17% of patients with Hashimoto's thyroiditis with no eye disease but were not detected in patients with nonautoimmune thyroid disorders in 25 normal subjects tested. In the majority of sera showing reactivity with this protein, reactivity with membrane antigens of 55 and 95 kDa also were observed, suggesting that the three proteins were conformationally associated. Cytotoxic antibodies against human eye muscle cells, measured in antibody-dependent cell-mediated cytotoxicity (ADCC), were demonstrated in 37% of patients with ophthalmopathy. There was no significant correlation, in patients with eye disease, between positive ADCC tests and antibodies to the 64 kDa protein, the 64 kDa reactive antibody being found in 50% of patients with positive ADCC and in 35% of those with negative tests. In this study, a clear association has been shown between thyroid-associated ophthalmopathy and the detection, in immunoblotting, of antibodies reactive with a 64 kDa eye muscle membrane antigen.(ABSTRACT TRUNCATED AT 250 WORDS)

Isotype and immunoglobulin subclass distribution of eye muscle membrane reactive antibodies in the serum of patients with thyroid-associated ophthalmopathy as detected in Western blotting

We have determined the immunoglobulin (Ig) class (isotype) and IgG subclass of autoantibodies in the serum of patients with thyroid-associated ophthalmopathy (TAO) or autoimmune thyroid disorders without evident ophthalmopathy reactive in Western blotting with antigens of 55, 64, 75 and 95 kDa in pig eye muscle membrane (PEMM). The 22 sera studied were shown, previously, to contain IgG antibodies reactive with one or more of the four antigens. The majority of sera antibodies reactive with PEMM antigens were of two or more IgG subclasses. Of the IgG subclass specificities IgG3 and IgG4 subclass antibodies were, overall, the most common. We were unable to demonstrate IgG subclass restriction for antibodies reactive with the 95 or 55 kDa antigens in PEMM, antibody activity being equally distributed in all four subclasses tested. While most of the sera which recognized a 64 kDa antigen did so with an IgG4 antibody, all other subclasses were also represented. On the other hand all 13 sera reactive with a 75 kDa antigen did so using Ig of the IgG3 subclass and 12 of these used the IgG4 subclass as well, IgG1 and IgG2 subclasses being represented in only 3 and 4 sera, respectively. There were no differences, in respect to Ig class or IgG subclass distribution of eye muscle reactive antibodies between patients with Graves' hyperthyroidism with ophthalmopathy and those with Hashimoto's thyroiditis, and eye disease. Control sera from five normal subjects and three patients with nonautoimmune thyroid disorders did not contain antibodies reactive with these PEMM antigens of any Ig class or IgG subclass.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunologically mediated cytotoxicity against human eye muscle and thyroid cells in euthyroid and thyrotoxic Graves' ophthalmopathy

We have studied the role of eye muscle and thyroid autoimmunity in patients with Graves' hyperthyroidism with or without ophthalmopathy in an area of relatively low iodine intake. Antibody dependent cell mediated cytotoxicity (ADCC) and complement mediated antibody dependent cytotoxicity (CMAC) against thyroid and eye muscle cells, and levels of antibodies against TSH receptor antigen and the thyroid microsomal antigen (thyroid peroxidase) were determined in three groups of patients: (1) thyrotoxic with exophthalmos (TX, n = 28), (2) thyrotoxic without ophthalmopathy (GR, n = 10), and (3) euthyroid ophthalmopathy (EU, n = 12). The thyroid glandular mass of the EU group was significantly less (P less than 0.01) compared with TX or GR. Mean (+/- SD) TSH receptor antibody (TRAb) level was 27 +/- 14% in EU which was significantly lower compared with TX (52.4 +/- 20%) and GR (59 +/- 18%). The prevalence of microsomal antibodies were similar and not significantly different in the three groups. On the other hand the prevalence of positive ADCC and CMAC tests was significantly greater, and at higher levels, in EU (ADCC THY CELLS 10.9 +/- 8.9% SL, ADCC Eye muscle = 25.9 +/- 20% SL, CMAC = 70.2 +/- 43% SL) and TX (ADCC THY CELLS = 9.3 +/- 9.2% SL, ADCC Eye muscle = 20.1 +/- 19% SL, CMAC = 62.4 +/- 30% SL) compared to GR (ADCC THY CELLS = 4.4 +/- 9.5% SL, ADCC Eye muscle = 7.7 +/- 6.7% SL, CMAC = 24.7 +/- 23% SL).(ABSTRACT TRUNCATED AT 250 WORDS)

[Clinical study on the diagnosis and treatment of retrosternal infection after median sternotomy]

From June 1964 to Dec. 1989, 1228 patients underwent cardiovascular operations by median sternotomy approach in our hospital. 18 of them (1.4%) were complicated by retrosternal infections and were treated successfully. Of these 18, 3 were treated by conservative method (Group 1), that is, local debridement and drainage. The other 15 were managed by a radical technique (Group 2) which includes reopening of the chest, radical debridement of retrosternal mediastinum, primary sternal reclosure and continuous retrosternal irrigation with antibiotic solutions. There was no hospital death. The mean healing time of the infected wounds was 91 days in Group 1, and 24 days in Group 2. Recurrence of wound infections was found in 2 cases in Group 1. Primary healing was obtained in all patients but 1 in Group 2 after initial debridement. The authors considered that (1) Early radical debridement with continuous irrigation is very effective for management of retrosternal infection; (2) Radical debridement should be done as early as the diagnosis of infection is established.

Specific interaction of a partially purified Xenopus transcription factor IIIC (TFIIIC) with frog tRNA gene

Transcription factor IIIC (TFIIIC) from Xenopus has been partially purified and characterized. Footprinting analyses indicate that a partially purified TFIIIC fraction contains an activity which specifically recognizes the "B" block element of tRNA gene. In addition, two other regions located downstream from the "B" block sequence are also protected. Protection experiments on 5S genes by DNAase I with either TFIIIC alone or TFIIIA and TFIIIC produced a minimal change in the cleavage pattern implying that TFIIIC does not intimately associate with DNA. The implications of these findings in relation to the class III gene transcription are discussed.

Patients with endocrine ophthalmopathy not associated with overt thyroid disease have multiple thyroid immunological abnormalities

Twenty-two apparently euthyroid patients with endocrine ophthalmopathy not associated with goiter, antithyroid microsomal or antithyroglobulin antibodies, or overt thyroid disease (so-called ophthalmic Graves' disease) were tested for subclinical hyperthyroidism or hypothyroidism. We measured 131I uptake and scan, serum T3 (by RIA), and serum TSH using a sensitive (by immunoradiometric assay) assay. Three patients were found to be hyperthyroid, and 1 was hypothyroid. The remaining 18 patients, who remained euthyroid throughout the study period, were investigated for evidence for antibody-mediated immunity against thyroid antigens. We measured antibody-dependent cell-mediated cytotoxicity against fresh thyroid cells using a 51chromium release assay, thyroid membrane-reactive antibodies in an enzyme-linked immunosorbent assay incorporating solubilized thyroid membranes, and TSH receptor-binding antibodies using a RRA and carried out sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting with patient sera for antibodies reactive with 64 and 110 kDa (thyroid peroxidase) membrane proteins. Bands were demonstrated, on SDS-PAGE, at 64 or 110 kDa in 13 patients, antibody-dependent cell-mediated cytotoxicity tests were positive in 7 patients, and enzyme-linked immunosorbent assay was positive in 4 of the 17 patients tested. In addition, TSH receptor antibody tests were positive in 5 patients, none of whom had other evidence for hyperthyroidism. Finally, significant lymphocyte infiltration was demonstrated on aspiration biopsy in 3 patients. All 18 patients had positive tests in at least 1 of the immunological assays. We believe that these data support the hypothesis that endocrine ophthalmopathy always occurs in patients with overt or subclinical Graves' hyperthyroidism, Hashimoto's thyroiditis, or thyroid immunological abnormalities. Those patients previously described as having euthyroid Graves' disease should, thus, be considered to have associated thyroid immunological abnormalities even though histological confirmation (from aspiration needle biopsy) may be obtained in only a minority of the patients. The possibility that the mechanism for this close association is cross-reactivity of cytotoxic antibodies against a thyroid/eye muscle cell surface shared antigen is discussed in the context of recent evidence from the authors' laboratory.

Partial purification and characterization of human megakaryocyte colony-stimulating factor (Meg-CSF)

Megakaryocyte colony-stimulating factor (Meg-CSF) in urinary extracts from patients with aplastic anemia was partially characterized and purified. Using Meg-CSF-enriched fractions, we established that the moiety has the following characteristics: 1) portions of the molecules having Meg-CSF activity have sialic acid, probably with a biantennary structure, and beta-galactose residues as the terminal and penultimate sugars; 2) disulfide residues are an essential chemical group of the molecule and are located on its surface; and 3) Meg-CSF activity is stable in n-propanol, but not in acetonitrile with trifluoroacetic acid. Partial purification of Meg-CSF by a four-step procedure of ethanol precipitation, CM Affi-Gel Blue chromatography, wheat germ agglutinin-sepharose chromatography, and high-resolution hydroxyapatite chromatography, yielded a concentrate with a 430- to 630-fold increase in specific activity. The partially purified Meg-CSF fractions stimulated both human and murine megakaryocytopoiesis in vitro (CFU-meg). When analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis under nonreduced conditions, Meg-CSF activity was recovered in the 29-34 kDa molecular weight fractions. We have also shown that Meg-CSF, purified from the urine of aplastic anemia patients, stimulated murine megakaryocytopoiesis and platelet production in vivo. Final purification of human urinary Meg-CSF is currently in progress.

[Flow cytometry in determination of DNA content of lymphoid cells: study of methodology and its preliminary clinical application]

The methodology of flow cytometry (FCM) in the determination of DNA content of lymphoid cells was studied. We conclude that the optimal conditions for the Ortho Instruments L-30 Cytofluorograf flow cytometer are as follows: 70% ethanol should be used as fixative and propidium iodide as DNA fluorescent stain at a final concentration of 50 micrograms/ml. RNase and Triton-X-100 added to the mixture and the use of fresh chicken red blood cells (CRBC) as internal standard will ensure the reliability of the data. The interference of doublet cells is eliminated by selecting single cell area signals. We discovered that aneuploidy detection can be optimized by using the coefficient of variation ratio (CVR) together with the DNA ratio (DR). A special computer program was written to calculate the percentage of cells in different phases of the cell cycle, according to DNA histograms derived from FCM. Based on assessment of the DNA content of lymphoid cells of 33 normal subjects, the normal ranges of DR, CVR and S% were found to be 2.57-2.83, 1.02 and less than 9.6% respectively. The diagnosis of two cases of lymphoid cell malignancy is reported and the potential of this method for wide clinical application discussed.

The influences of islet transplantation on metabolic abnormalities and diabetic complications

To assess the long-term effect of islet transplantation on metabolic abnormalities and chronic complications of diabetic recipients, the long-term follow-up data of 36 type 1 diabetic subjects with functioning islet grafts for more than 1 year were analysed in this article. 36 type 1 diabetics, with mean age of 34.30 +/- 12.05 yr and mean duration of 11.53 +/- 5.29 yr, were followed up for a mean period of 29.39 +/- 9.50 mo after successfully transplanting with short-term cultured islet tissue of human fetal pancreases. The effect of islet transplants was identified as excellent in 13 subjects, good in 12 and fair in 11. The comparative studies were carried out of the mean levels of serum C-peptide, plasma glucose, GHb and GPP, serum lipids, and mean excretion of urine sugar, and the diabetic retinopathy, nephropathy as well as the autonomic neuropathy before transplantation in comparison with those of the present. The results of the study demonstrated that islet transplants could improve the function of islet B cells and the glucose metabolism, and might delay the development of diabetic retinopathy, nephropathy and autonomic neuropathy in successfully transplanted diabetic recipients, but not exert any influences on those of patients in fair group.

Failure to detect complement-mediated antibody-dependent cytotoxicity against human orbital tissue cells in the serum of patients with thyroid-associated ophthalmopathy

Antibodies which are cytotoxic to human eye muscle cells and orbital fibroblasts in antibody dependent cell-mediated cytotoxicity (ADCC) are routinely detected in the serum of patients with thyroid-associated ophthalmopathy (TAO). In the present study sera from patients with TAO, most of which were shown to be positive in ADCC against eye muscle cell targets, were tested for complement-mediated antibody-dependent cytotoxicity (CMAC) against human and pig eye muscle cells, human (abdominal) skeletal muscle cells and human orbital fibroblasts, in 51Cr release assays. Several different assay protocols and complement sources were used and patient and age, sex matched normal sera compared. In preliminary studies tests were always negative when eye muscle cells, other skeletal muscle cells, or orbital fibroblasts were used as targets, regardless of the complement source, or concentration, or assay conditions used. When larger numbers of patients and normals were tested in a single assay mean (+/- SE) % specific lysis for patients with TAO was not significantly different from that for normals for either eye muscle cells or other skeletal muscle cells and taking the upper limit of normal as mean + 2 SD for the normals, tests were positive in no patient with either target. On the other hand ADCC tests were positive in 57% of the same sera tested with the same eye muscle cell targets. When human thyroid cells were used as targets, tests were positive in 10 of the 14 patients tested and monoclonal antibodies, in enzyme-linked immunosorbent assay, reactive with eye muscle antigens gave positive lysis of eye muscle cells.2+ t