The products of transferred H-2 genes express determinants that restrict hapten-specific cytotoxic T cells

Cell lines into which cloned H-2 genes had been introduced (i.e., transformants) were used to correlate the genes and their products that are capable of functioning as H-2 restriction elements for hapten-self-(AED and TNP) specific cytotoxic T cells (CTL). These transformants provided a unique system in which major histocompatibility restricted (MHC) T cell recognition could be examined by using cells that express only H-2Ld or only H-2Dd gene products. BALB/c (H-2d) anti AED-self CTL lysed both the H-2Ld and Dd transformants, but not parental, i.e., untransformed, cells. The AED-self lysis of the Ld and Dd transformants was shown to be specifically inhibited by anti-H-2Ld and anti H-2Dd monoclonal antibody, respectively. In contrast to these results, BALB/c anti TNP-self CTL were found to lyse readily the Dd but not Ld transformed lines, supporting reports indicating that H-2Ld-restricted TNP-self CTL could not be detected. The results of this study thus demonstrate that the cell surface products encoded by these transferred MHC class I genes contain self determinants recognized by CTL.

Absence of mutagenic activity of WHR-1142A, lidamidine hydrochloride, in 4 short-term tests for mutagenic/carcinogenic potential

WHR-1142A, lidamidine hydrochloride, an antidiarrhoeal agent, was tested for possible mutagenic/carcinogenic activity in the Ames Salmonella typhimurium/metabolic activation test, the micronucleus test, by analysis of metaphase chromosomes obtained from human lymphocytes grown in culture and in a cell transformation assay. No evidence of mutagenic/carcinogenic activity due to WHR-1142A, lidamidine hydrochloride, was found in any of the 4 tests.

An evaluation of the mutagenic potential of 2-(2',4'-diaminophenoxy)ethanol using the micronucleus test

The micronucleus test in mice was used to investigate the mutagenic potential of 2-(2',4'-diaminophenoxy)ethanol. The test compound was administered by oral gavage to CD-1 mice (ICR derived) as 2 equal dosages of 250,500 and 1000 mg/kg bodyweight. Bone-marrow smears were examined for the presence of micronucleated cells in 2000 polychromatic erythrocytes per animal. In addition, the ratio of normochromatic to polychromatic erythrocytes was scored to provide an indication of the toxicity of the test compound to bone marrow cells. No increase in the incidence of micronucleated polychromatic erythrocytes was observed for any group dosed with 2-(2',4'-diaminophenoxy)ethanol, although evidence of bone-marrow toxicity was observed at all 3 dosages.

Isolation and culture of renal cortical tubules from neonate rabbit kidneys

A method is described for the preparation of an enriched population of proximal tubules from the cortices of neonate (21-28 d old) rabbits. The method uses collagenase-hyaluronidase digestion, followed by gentle shear to yield a suspension of tubules and glomeruli. Tubular enrichment is achieved by discontinuous density gradient centrifugation in a Percoll gradient. Two fractions were obtained by this method. The denser fraction contained predominantly proximal tubules, was depleted of glomeruli and was enriched in the proximal tubule marker enzyme alkaline phosphatase. Qualitatively similar results to those obtained with neonate animals were obtained with adult tissue. Neonate tubules from the denser gradient fraction grew readily in tissue culture. When examined by electron microscopy the cells exhibited a marked polarity of ultrastructural organization and retained apical tight junctions. Despite this, there was an obvious loss of structure in comparison with in vivo proximal tubule cells. The use of primary culture techniques to study in vitro renal epithelial function is discussed.

Cell-mediated lympholytic responses against autologous cells modified with haptenic sulfhydryl reagents. I. Effector cells can recognize two distinct classes of hapten-reactive self sites on cell surface proteins

Mouse spleen cells were modified with a sulfhydryl-reactive reagent, N-iodoacetyl-N'-(5-sulfonic-1-naphthyl) ethylene diamine (I-AED) and used as stimulator cells in primary in vitro cultures with unmodified spleen cells of the same strain. CTL could be readily demonstrated when tested on hapten-modified syngeneic target cells. These CML responses were hapten specific and H-2 restricted. In the H-2b strain, effector cell populations were identified that recognized AED in association with K-end and D-end coded self MHC products. Functional modification of the target cells by I-AED can be effectively blocked by prereacting the cells with other SH-reagents, which is consistent with CTL recognition of the hapten on cysteine residues. Since these premodifications of the cell surface do not block the functional modification by trinitrobenzene sulfonate (TNBS), the sulfhydryl-reactive compounds and TNBS modify distinct classes of cell surface groups as determined by CTL function. The results of antibody inhibition experiments are also consistent with this interpretation. Using fluorescent labeled anti-hapten antibodies, FACS II analysis showed that there are approximately 20-fold fewer AED than TNP groups on the approximately 20-fold fewer AED than TNP groups on the cell surface when equivalent concentrations of I-AED and TNBS are compared. The possibility is discussed that these sulfhydryl-reactive compounds can be used together with the H-2Kb mutants for the localization of H-2 coded self determinants recognized in association with foreign antigens.

Cell-mediated lympholytic responses against autologous cells modified with haptenic sulfhydryl reagents. I. Effector cells can recognize two distinct classes of hapten-reactive self sites on cell surface proteins

Mouse spleen cells were modified with a sulfhydryl-reactive reagent, N-iodoacetyl-N'-(5-sulfonic-1-naphthyl) ethylene diamine (I-AED) and used as stimulator cells in primary in vitro cultures with unmodified spleen cells of the same strain. CTL could be readily demonstrated when tested on hapten-modified syngeneic target cells. These CML responses were hapten specific and H-2 restricted. In the H-2b strain, effector cell populations were identified that recognized AED in association with K-end and D-end coded self MHC products. Functional modification of the target cells by I-AED can be effectively blocked by prereacting the cells with other SH-reagents, which is consistent with CTL recognition of the hapten on cysteine residues. Since these premodifications of the cell surface do not block the functional modification by trinitrobenzene sulfonate (TNBS), the sulfhydryl-reactive compounds and TNBS modify distinct classes of cell surface groups as determined by CTL function. The results of antibody inhibition experiments are also consistent with this interpretation. Using fluorescent labeled anti-hapten antibodies, FACS II analysis showed that there are approximately 20-fold fewer AED than TNP groups on the approximately 20-fold fewer AED than TNP groups on the cell surface when equivalent concentrations of I-AED and TNBS are compared. The possibility is discussed that these sulfhydryl-reactive compounds can be used together with the H-2Kb mutants for the localization of H-2 coded self determinants recognized in association with foreign antigens.

Identification of two strains of MDCK cells which resemble separate nephron tubule segments

Cultured monolayers of dog kidney (MDCK) cells display many features of in vivo epithelia. This work describes the identification of two separate strains of MDCK cell with entirely different properties. Strain I cells form epithelial monolayers which display a high electrical resistance (4.1 k omega . cm-2); the basal short-circuit is small (approx. 0.5 muamp . cm-2) and is stimulated by adrenaline (1 micrometer) prostaglandin E1 (1 micrometer) and arginine vasopressin (2 micrometer) added to the basal bathing solution. Strain II cells form epithelial monolayers of low electrical resistance; the short circuit current is insensitive to adrenaline, prostaglandin E1 and vasopressin. Strain II cells possess measurable activities of alkaline phosphatase and gamma-glutamyl transpeptidase whereas Strain I cells do not. The specific activity of the (Na+ + K+)-ATPase is two-fold greater in Strain II compared with Strain I. The polypeptide composition of the apical membrane differs substantially between the two cell strains as revealed by radio-iodination of external membrane proteins. Monolayer morphology is substantially different between two cell strains. The results are discussed in relation to previous work on MDCK epithelial and the two types of cell monolayer compared with in vivo tubule segments.

The polypeptides of rat liver nuclear envelope. II. Comparison of rat liver nuclear membrane polypeptides with those of the rough endoplasmic reticulum

Nuclear envelopes are separated into pore-lamina and membrane sub-fractions by extraction in 2.0% Triton X-100 followed by pelleting of the pore-laminae. The polypeptides of these subfractions are then compared with those from isolated rough endoplasmic reticulum. The dispositions of individual polypeptides in the cytoplasmic surface of nuclear envelopes and rought endoplasmic reticulum were studied by lactoperoxidase-catalysed iodination. These studies show that although the nuclear membranes exhibit several homologies with the Triton-soluble polypeptides of the rough endoplasmic reticulum the relative proportion of individual polypeptides within the two systems are very largely different. The cytoplasmic surfaces of the 2 membrane systems show only 2 obvious homologies at 105 000 and 15 000 mol. wt and the overall impression is that, at least in rat liver, the outer nuclear membrane is very substantially differentiated from rough endoplasmic reticulum. It is concluded that the nuclear membranes may not be regarded as a mere continuum of the endoplasmic reticulum, but should be seen as a highly specialized membrane system in their own right.

The polypeptides of rat liver nuclear envelope. I. Examination by nuclear pore complex polypeptides by solid-state lactoperoxidase labelling

Purified nuclei retaining a high degree of ultrastructural integrity were isolated by conventional centrifugation techniques. The cytoplasmic surface of these nuclei was iodinated using lactoperoxidase immobilized onto giant Sepharose beads; thus the outer nuclear membrane and the cytoplasmic surface of nuclear pore complexes were selectively labelled. Pore complexes in association with a fibrous lamina were isolated from these nuclei by removal of the nucleoplasm and extraction with Triton X-100. The chemical composition of the pore-lamina fraction was 93.6% protein, 6% RNA, 0.4% phospholipid. The labelling suggests that major polypeptides N1 (70 000) and N2 (67 000) and more than 10 other more minor polypeptides, ranging from 33 000 to 200 000 mol. wt, as being components of the nuclear pore complex. Polypeptide N3 (58 000) is shown to be present only on the nucleoplasmic face of nuclear envelopes, probably in the fibrous lamina.

Pontine infarction manifesting as isolated cranial nerve palsies

Isolated ipsilateral fifth, seventh, tenth and twelfth cranial nerve palsies in a 74-year-old woman were shown at autopsy to result from an inferior lateral pontine infarction. The clinical features and pathogenesis of this uncommon lesion are discussed.

Strokes and head injury

This is a report of a series of patients who suffered major cerebral hemorrhage or infarction complicating industrial head injuries. The variable importance of trauma and of pre-existing vascular disease is exemplified. Accuracy of assessment of such complex problems is facilitated by modern applied neuroscientific techniques.

Anaesthetic management of thoracotomy in the presence of chronic carbon dioxide retention

A patient suffering from chronic carbon dioxide retention with persistent pneumothorax, following spontaneous rupture of an emphysematous bulla, underwent thoracotomy. The surgical and anaesthetic management are reported.

Examination of the potential mutagenicity of hair dye constituents using the micronucleus test

12 compounds which are constituents of hair dyes or chemically related aromatic amines, aminophenols, their nitroderivatives and aromatic hydroxyderivatives were examined for evidence of mutagenic potential by means of the micronucleus test. None of the compounds tested caused an increase in the incidence of micronucleated erythrocytes after oral dosing.

Beneficial effects of serotonin precursors in postanoxic action myoclonus

In two patients with postanoxic action myoclonus, L-tryptophan or a monoamine oxidase inhibitor induced a moderate improvement, but L-5-hydroxytryptophan had greater therapeutic effect. Methysergide, a potent blocker of serotonin receptors, consistently induced a marked deterioration in myoclonus. Pretreatment cerebrospinal fluid 5-hydroxyindoleacetic acid levels were reduced significantly in both patients. These findings suggest that postanoxic action myoclonus likely is associated with insufficient serotonergic activity in the central nervous system. Data are inadequate to determine whether this apparent insufficiency reflects structural changes in 5HT-containing raphe nuclei due to a direct anoxic damage to these structures of functional changes caused by a secondary reduction in the activity of intact serotonergic neurons.

An evaluation of the mutagenicity of the cutting oil preservative Grotan BK

The micronucleus test in rats was used to investigate the mutagenic potential of Grotan BK, a preserving agent used in industrial cutting oils. The test compound was administered either by intragastric intubation, dermal application or subcutaneous injection. CFHB (Wistar) rats were given two equal dosages separated by 24 h to provide total dosages of 15,60,240 or 960 mg/kg. In addition, as a positive control, benzidine at a total dosage of 409.6 mg/kg was administered similarly by the dermal and subcutaneous routes. Bone marrow preparations were screened for the presence of micronucleated cells in 2000 polychromatic erythrocytes. No increase in the incidence of micronucleated erythrocytes was observed for any group given Grotan BK by any of the three administration routes, or at any dose level. Benzidine induced high incidences of microcucleated erythrocytes following both dermal application and subcutaneous injection.

Clinical problems of motor system disease

This prologue to a symposium of research studies on motor mechanisms is a general commentary by a clinical neurologist. The vast extent and intricacy of modern basic neurological scientific knowledge presents a rather bewildering challenge to reasonable clinical application. In some degree this is being handled by complex and diverse neurological subspecialization. It is recalled that many past advances in the knowledge of neurological disease were achieved by a series of alternating and supporting bedside and laboratory observations and studies.

Spontaneous incarcerated herniation of the spinal cord into a vertebral body: a unique cause of paraplegia. Case report

✓ A case of progressive paraparesis is reported in which the normal spinal cord herniated through a defect in the ventral meninges and dura and became incarcerated in a cavity in the dorsal aspect of the body of T-7. Progress of the paraparesis was arrested by reduction of the hernia.

Syringomyelia: a clinical review of 75 cases

Records of 75 patients with syringomyelia are reviewed. Their clinical course fell into one of three main groups: (1) those with a long history of a steadily progressive disability; (2) those with a long history but little or no progression of their disability; and (3) those with a short, fairly rapid downhill course.On the basis of this study, x-ray therapy seems to be of little value in the treatment of this disease. Surgical treatment on the other hand appears to offer more hope for a selected group of patients who are progressing at the time of examination. In this group surgery is recommended (1) in the presence of a foramen magnum anomaly with signs and symptoms related to this deformity; (2) in the presence of a distended cord with pain and evidence of a spinal fluid block; and (3) when the possibility of an ependymoma exists.

Pitfalls in Diagnosis and Treatment of Cerebral Arterial Insufficiency

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RECURRENT SUBARACHNOID HAEMORRHAGE DUE TO AN ARTERIAL ANGIOMA OF THE CEREBELLUM AND BRAIN-STEM

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Spontaneous Hæmatomyelia: a Report of Two Cases, one in Association with an Intramedullary Angioma, and the other in Association with Syphilis

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