Dissociative disorder presenting as catatonia

Three cases of dissociative disorder presenting with catatonia are described. Catatonia is generally believed to be associated with schizophrenia. However, many other conditions are also known to cause catatonia. A brief review of literature is provided. All the cases improved rapidly with a few ECTs. This report aims to highlight the presentation of dissociative disorders with catatonia. It also seeks to bring to notice the need to avoid lumping all non-organic catatonics under the rubric of schizophrenia so as to ensure proper treatment.

Coronary artery bypass grafting in dextrocardia with situs inversus totalis

Dextrocardia with situs inversus totalis is a rare congenital abnormality of development involving a left-handed malrotation of the visceral organs. The incidence of coronary artery disease in this condition is probably similar to that in the general population. We report herein the case of a 62-year-old man with dextrocardia and situs inversus totalis who underwent myocardial revascularization by the use of right internal mammary artery and radial artery.

Leptospirosis and Weil's disease in eastern India

Leptospirosis is characterised by a broad spectrum of clinical manifestations varying from inapparent infection to fulminant fatal disease. Severe leptospirosis characterised by profound jaundice is referred to as Weil's disease. In the present study 20 patients of leptospirosis, of which 7 belonged to Weil's disease, were diagnosed based on the demonstration of IgM antileptospira antibody and supported by clinical correlation and appropriate biochemical markers. Overall, the male and female ratio was 17:3 and the same ratio for the Weil's disease was 6:1. The most common presentation involved fever, malaise and myalgia. Conjunctival congestion was found in 75% of the cases and jaundice was encountered in 90% of the cases. The prognosis of all these patients, including that of Weil's disease was excellent. Early recognition and initiation of antibiotic therapy were found to be important.

Inhibition of apoptosis by primary isolates of herpes simplex virus

HSV-1 inhibits apoptosis of the infected cell, presumably to increase viral yield. Weaker anti-apoptotic activity was previously reported in laboratory-adapted HSV-2, but not in two low-passage clinical HSV-2 isolates, suggesting that the anti-apoptotic effect might result from adaptation to laboratory growth. We therefore assembled a large panel of clinical strains of HSV-1 and HSV-2. Clinical and laboratory strains of HSV-1 strongly inhibited apoptosis of Jurkat cells, as determined by morphologic change or caspase activation, while clinical HSV-2 strains showed no inhibitory activity in Jurkat cells. These findings suggest fundamental differences between HSV-1 and HSV-2 in their manipulation of host cell apoptosis.

Overexpression of Smad2 reveals its concerted action with Smad4 in regulating TGF-beta-mediated epidermal homeostasis

Members of the transforming growth factor-beta (TGF-beta) superfamily are critical regulators for epithelial growth and can alter the differentiation of keratinocytes. Transduction of TGF-beta signaling depends on the phosphorylation and activation of Smad proteins by heteromeric complexes of ligand-specific type I and II receptors. To understand the function of TGF-beta and activin-specific Smad, we generated transgenic mice that overexpress Smad2 in epidermis under the control of keratin 14 promoter. Overexpression of Smad2 increases endogenous Smad4 and TGF-beta 1 expression while heterozygous loss of Smad2 reduces their expression levels, suggesting a concerted action of Smad2 and -4 in regulating TGF-beta signaling during skin development. These transgenic mice have delayed hair growth, underdeveloped ears, and shorter tails. In their skin, there is severe thickening of the epidermis with disorganized epidermal architecture, indistinguishable basement membrane, and dermal fibrosis. These abnormal phenotypes are due to increased proliferation of the basal epidermal cells and abnormalities in the program of keratinocyte differentiation. The ectodermally derived enamel structure is also abnormal. Collectively, our study presents the first in vivo evidence that, by providing an auto-feedback in TGF-beta signaling, Smad2 plays a pivotal role in regulating TGF-beta-mediated epidermal homeostasis.

Middle cerebral artery Doppler in severe intrauterine growth restriction

OBJECTIVE

To examine longitudinal changes in middle cerebral artery blood flow assessed by Doppler in severely growth restricted fetuses.

METHODS

Eighteen structurally normal singleton pregnancies complicated by suspected intrauterine growth restriction were monitored by serial measurement of the pulsatility index of the middle cerebral artery over 7 to 72 days. Outcome measures included indication for delivery, umbilical venous pH and admission to and length of stay in neonatal intensive care.

RESULTS

Thirteen fetuses demonstrated severe intrauterine growth restriction based on subsequent birth weights being below the 2.5th centile, two had intrauterine growth restriction (birth weights between the 2.5th and 5th centiles), and three had birth weights between the 5th and 50th centiles. The middle cerebral artery pulsatility index showed rapid and sharp changes between examinations in those severely growth restricted fetuses which required delivery before 34 weeks. This pattern was not obvious in severely growth restricted fetuses delivered after 34 weeks, or in those less severely growth restricted, regardless of the gestation at delivery. Changes in middle cerebral artery pulsatility index contributed to the decision to deliver in three cases. The middle cerebral artery pulsatility index demonstrated greater variation in those fetuses with cord pHs of less than 7.25. The length of stay in neonatal intensive care decreased with increasing gestational age and birth weight.

CONCLUSIONS

The difference in the pattern of change in middle cerebral artery pulsatility index in intrauterine growth restricted fetuses may be a reflection of maturity in addition to the degree of fetal compromise. The decision to deliver was multifactorial. The middle cerebral artery pulsatility index only influenced the decision to deliver when changes in other parameters were evident.

Translocation of a copper 7 intra-uterine contraceptive device with subsequent penetration of the caecum: case report and review

A case of translocated Copper 7 intra-uterine contraceptive device with impending caecal penetration is reported and discussed.

Altered solution structure of alcoholic medium of potentized Nux vomica underlies its antialcoholic effect

Nux vomica 30c, 200c and 1000c were administered orally to three batches of albino mice for three days. Six hours after the last dose on the third day the mice were injected i.p. with ethanol 4g/kg body wt. They lost their righting reflex and lay motionless apparently sleeping due to alcohol. Mice treated with three potencies of Nux vomica regained their righting reflex more quickly than the corresponding untreated controls. Each of the three batches of mice was tested twice for ethanol sedation, once with a potency of Nux vomica and another time with a placebo control. The time interval between drug treatment and control was 10 days. NMR spectra of Nux 30, Nux 200, Nux 1000, alcohol 30, alcohol 30 (unagitated) and 90% alcohol showed significant difference from each other with respect to the spin-lattice relaxation time (T1) of the deuterium nuclei. This gives a measurable physical basis of the effective high potencies of Nux vomica.

The elimination profiles of tenoxicam and hydroxytenoxicam in equine urine and serum after a 200-mg oral dose

Tenoxicam (Mobiflex) was administered orally to four standardbred mares at a dose of 200 mg. Elimination profiles of tenoxicam and hydroxytenoxicam were generated based on quantitation of these analytes in urine and serum by liquid chromatography (LC) with ultraviolet detection. Tenoxicam was confirmed by LC-tandem mass spectrometry daughter ion mass spectra in the last postadministration sample in which tenoxicam was detected. The tenoxicam and hydroxytenoxicam urinary elimination profiles had the same shape for the same horse; however, each horse was significantly different from the others. One horse (Horse 15) showed a much broader and flatter elimination profile than the other horses. Each horse had a peak in analyte concentration at different collection times. The latest detection for both tenoxicam and hydroxytenoxicam was 29-31 h for all horses. The urinary tenoxicam limit of detection (LOD) and limit of quantitation (LOQ) were 0.3 and 0.4 microg/mL, respectively. The urinary hydroxytenoxicam LOD and LOQ were 0.6 and 0.8 microg/mL, respectively. Hydroxytenoxicam was found to be completely conjugated and tenoxicam completely unconjugated in equine urine. Serum elimination profiles of tenoxicam were measured to 120 h postadministration. Hydroxytenoxicam was not detected in postadministration serum. The last serum tenoxicam detection was at the 24-h collection time for all horses. The peak average concentration was 434.5 ng/mL at 3 h. The serum tenoxicam LOD and LOQ were 5.7 and 7.3 ng/mL.

The elimination profiles of oxaprozin in equine urine and serum after a 4.8-g dose

A method for the extraction of oxaprozin from equine urine and serum and its quantitation by high-performance liquid chromatography-ultraviolet detection is presented. Confirmation of oxaprozin in postadministration extracts was accomplished by gas chromatographic- mass spectrometric analysis of methylated extracts or liquid chromatography with tandem mass spectrometry daughter ion mass spectra of underivatized extracts. Daypro, a formulation of oxaprozin, was administered orally at a dose of 4.8 g to four standardbred mares. Urine and serum samples were collected to 120 h postadministration. Base hydrolysis of equine urine before extraction resulted in an increase in the amount of oxaprozin measured, an indication of conjugation by ester formation. The urinary elimination profiles of each horse were significantly different from each other with more than one peak in oxaprozin concentration before the 29-31-h collection time. After this collection time, the differences between the oxaprozin urinary concentrations of each horse follow each other more closely. The peak average urinary concentrations of oxaprozin were 25.1 and 17.0 microg/mL at collection times of 8-10 and 18-22 h, respectively. The latest detection of oxaprozin in urine was at the last collection time of 119-121 h postadministration at a concentration close to the detection limit of approximately 0.1 microg/mL. The serum elimination profiles do not vary between horses as much as the urinary elimination profiles. The peak average serum concentration was 49.0 microg/mL at a collection time of 6 h postadministration. The latest detection was at the last collection time of 120 h. Oxaprozin is metabolized in the horse by hydroxylation. Two major urinary metabolites were isolated and identified as hydroxylated oxaprozin. The two urinary metabolites were isolated from equine postadministration urine and analyzed by mass spectrometry and proton nuclear magnetic resonance spectroscopy, which showed that the hydroxylation had occurred at the para positions of the two aromatic rings.

Screen-printed amperometric biosensors for the rapid measurement of L- and D-amino acids

Screen-printed three-electrode amperometric sensors incorporating L- and/or D-amino acid oxidase for the general purpose measurement of L- or D-amino acids is described. The working electrode incorporates rhodinized carbon, to facilitate hydrogen peroxide oxidation at a decreased operating potential, and immobilized enzyme. The devices responded to all 20 common L-amino acids and all of the D-amino acids examined, the exceptions being L- and D-proline. Linear response profiles were observed for L-leucine, L-glycine and L-phenylalanine with limits of detection of 0.47, 0.15 and 0.20 mM respectively. The devices were reproducible and exhibited stability over a 56 d test period. The biosensor compares favourably with a standard photometric amino acid test and was used to monitor milk ageing effects. The assay is cheap, simple to perform and rapid, requiring only buffer-electrolyte and a small sample volume.

The urinary elimination profiles of diazepam and its metabolites, nordiazepam, temazepam, and oxazepam, in the equine after a 10-mg intramuscular dose

A method for the extraction of diazepam and its metabolites (nordiazepam, temazepam, and oxazepam) from equine urine and serum and their quantitation and confirmation by liquid chromatography-tandem mass spectrometry is presented. Valium, a formulation of diazepam, was administered at a dose of 10 mg intramuscularly to four standard-bred mares. Diazepam is extensively metabolized in the horse to nordiazepam, temazepam, and oxazepam. Diazepam urinary concentrations were found to be less than 6 ng/mL. Nordiazepam was found to be mainly in its glucuronide-conjugated form and was measured out to a collection time of 53-55 h. Oxazepam and temazepam were entirely conjugated, and their urinary concentrations were measured out to collection times of 121 h and 77-79 h, respectively. Diazepam and nordiazepam were measured in equine postadministration serum out to collection times of 6 and 54 h, respectively. Oxazepam and temazepam were not detected in postadministration serum.

Acute lung injury after massive household endotoxin exposure

Household exposures may result in a variety of respiratory illnesses. Most of these inhalation injuries are benign and self-limited. However, an acute injury that results in exacerbation of asthma or chronic fibrosing processes may be life-threatening. We report the case of a patient who suffered a massive household dust exposure when the bag of his upright vacuum cleaner exploded. Inhalation of the dust resulted in respiratory distress characterized by non-cardiogenic pulmonary edema. We believe this is the first report of acute respiratory distress syndrome (ARDS) as a result of endotoxin exposure from the inhalation of household dust.

Late clotted haemothorax after blunt chest trauma

A clotted haemothorax can develop any time after blunt chest trauma. Two cases are described in which late clotted haemothoraces developed which were treated by limited thoracotomy and evacuation of clots. Late clotted haemothorax may occur even in the absence of any abnormal initial clinical findings. Early detection and treatment is important to avoid the complications of fibrothorax and empyema with permanent pulmonary dysfunction. After blunt chest trauma patients should be advised to return to the accident and emergency department for assessment on development of any new chest symptom. Under these circumstances a chest x ray is mandatory to exclude a haemothorax.

A unique metabolite of nimesulide

Nimesulide is a nonsteroidal anti-inflammatory drug recently detected in equine blood and urine samples taken at the race track. The detection of the drug in a blood sample led to the identification of an unknown thin-layer chromatographic (TLC) spot in track urine samples as a metabolite of nimesulide. Characterization of the unknown TLC spot and comparison with the synthesized compound shows that the unknown TLC spot is a previously unreported equine metabolite of nimesulide. The metabolite was identified as resulting from the reduction of the nitro group on nimesulide to an amino group. This reduced nitro metabolite (4-amino-2-phenoxy-methanesulfonanilide) is a major metabolite of nimesulide in the equine.

Structural polypeptides of different clinical strains of avian adenovirus type-1

The polypeptides of two liver strains, two ovarian strains and one standard strain of avian adenovirus-1 (AAV-1) were analysed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), Western blot using polyclonal antibodies to all the strains and isoelectric focusing (IEF). All the strains had 11 polypeptides and molecular weight varied between 9 and 100 kDa. The polypeptide pattern was similar in all the strains as revealed by SDS-PAGE and Western blot. However, some differences among the strains on the basis of isoelectric point of polypeptide were observed by IEF.

Humoral immune response of chicks to different clinical isolates of avian adenovirus type-1

The humoral immune response of 7-day-old chicks to different strains of avian adenovirus (AAV) type-1 was determined by counter immunoelectrophoresis (CIE) and enzyme-linked immunosorbent assay (ELISA). In CIE antibody was detected 14 days post-infection (PI) whereas in ELISA antibody was detected 7 days PI. The ELISA titre reached its peak at 21 days PI in all groups. The pattern of immune response among the groups was found to be similar.

Visual influence on head shaking using the vestibular autorotation test

In this study we investigated the vestibular system by recording eye movements in response to voluntary high-frequency head-only movements using the Vestibular Autorotation Test (VAT; Western System Research Inc., Los Angeles, California). Our objective was to evaluate if the VAT could be implemented as one of the screening tests for vestibular integrity in aircrews and potential pilots. We attempted to record horizontal and vertical eye movements using electrooculography and head velocity with calibrated rotational velocity sensors. The gain and phase of the input and output signals were computed by discrete Fourier analysis. Seated subjects were instructed to fixate on a real or imaginary target while making smooth head oscillations about the spinal axis in time to an audible cue from 0.5 to 6.0 Hz/during an 18-second test period. Test trials included two conditions in the light with subjects fixated on a real target (C1) or on an imaginary target on a blank screen (C2); three conditions in the dark in which subjects fixated on an imaginary target (C3), fixated on a remembered LED target in the dark after it was extinguished (C4), or fixated on a real target (C5). All the dark trials were performed after dark adaptation for 30 minutes. We were not able to obtain consistent vertical VOR response (when the subjects oscillated their head about the interaural axis) using the VAT. For horizontal eye movements from 2.0 to just over 4.7 Hz, when subjects fixated on an imaginary target, there was an unexpected and significant increase in the gain of the eye movement velocities in the dark as compared to the gain obtained in the light conditions. In the dark trials, the gain was significantly higher when the subjects fixated on an imaginary target as opposed to a real target. There was no difference in phase among all conditions. This test could potentially serve for preliminary screening for the integrity of the vestibular system as it is noninvasive and of short duration. However, caution must be exercised in controlling various variables. Extensive normative data are needed to properly assess this test as a screening tool for aircrews.

An exploratory evaluation of ECT in haloperidol-treated DSM-IIIR schizophreniform disorder

In a double-blind, prospective study, 30 consecutive treatment-naive adult men with first-onset psychosis and DSM-IIIR provisional schizophreniform disorder (without good prognostic features) were randomized into true electroconvulsive therapy (ECT) and sham ECT groups. Both groups received haloperidol in a fixed dose of 15 mg at night. The ECT schedule comprised six bilateral, sinusoidal wave treatments administered on alternate days, thrice a week. Weekly ratings for the first 6 weeks showed an absence of significant difference between the groups in the number of patients responding and in the rate of attenuation of psychosis; severity of depression, while less in the true ECT group after the first 3 weeks, did not differ between the groups at any subsequent time point. Clinical ratings were repeated at 6 months, and social functioning was assessed; again, no group differences emerged. It is concluded that ECT does not meaningfully improve response in unselected schizophreniform disorder that is treated with an adequate dose of neuroleptic.

Loss of RT6 message and most circulating T cells after thymectomy of diabetes prone BB rats

T cells expressing the RT6 surface alloantigen perform important immunoregulatory functions in the rat. Diabetes prone (DP) BB rats are deficient in circulating RT6+ T cells and develop spontaneous autoimmune diabetes mellitus. Transfusions leading to engraftment of RT6+ T cells prevent the disease. Coisogenic diabetes resistant (DR) BB rats do circulate RT6+ T cells and are free of disease. We investigated the basis for the deficiency of RT6+ T cells in the DP-BB rat and made the following observations. 1. Thymectomy causes the rapid loss of most peripheral T cells in the DP-BB rat. 2. Concomitant with the loss of T cells is the total loss of mRNA encoding RT6. 3. In contrast to the effects observed in peripheral lymphoid tissues, thymectomy does not lead to a detectable loss in RT6+ protein found in the small intestine. We conclude that the deficiency of RT6+ peripheral T cells in the DP-BB rat is due either to their short life span or to their reduced proliferative capacity following release from the thymus.

An RT6a gene is transcribed and translated in lymphopenic diabetes-prone BB rats

T-cells expressing the RT6 surface alloantigen appear to perform important immunoregulatory functions in the rat. Diabetes-prone BB rats lack circulating RT6+ T-cells and spontaneously develop autoimmune diabetes mellitus and thyroiditis. The coisogenic diabetes-resistant BB rat does circulate RT6+ T-cells and is free of disease. Transfusions leading to engraftment of RT6+ T-cells prevent both diabetes and thyroiditis in the diabetes-prone rat. To investigate the absence of this subset in the lymphopenic BB rat, we used both molecular and biochemical procedures and made the following observations: 1) an mRNA encoding RT6 protein is present in diabetes-prone spleen cells; 2) nucleotide sequencing of this transcript reveals an intact coding sequence for the RT6.1 alloantigen; 3) sensitive chemiluminescent assay of diabetes-prone lymph node cell detergent extracts shows that diabetes-prone RT6 mRNA is translated in vivo; 4) quantitatively, diabetes-prone lymph node cells express < or = 10% of the RT6.1 protein found on similar numbers of diabetes-resistant BB cells; and 5) finally, we obtained evidence of an intact phosphatidylinositol linkage of the molecule to the cell surface and successfully immunoprecipitated the phosphatidylinositol-linked protein with DS4.23 monoclonal antibody, indicating that the RT6.1 antigen is correctly processed and folded in diabetes-prone lymph node cells. We conclude that the near total absence of RT6+ T-cells in the diabetes-prone BB rat is unlikely to be because of a defect in RT6 gene expression per se. Defects in RT6 gene regulation or other cellular defects leading to premature cell death in the T-cell lineage, alone or in combination, may instead be responsible.

Detection of rabies virus in different tissues of experimentally infected mice at preclinical and postclinical stages of the disease

Rabies fixed virus (CVS) was passaged 10 times in mice by intramuscular (im) route followed by experimental inoculation of the titrated virus in 4 groups of mice with the dose of 0.1 ml of 1000 mouse (LD50 0.03 ml) using intracerebral (ic), intravenous (iv), intramuscular (im), intraocular (io), and intranasal (in) routes respectively. No marked variation in clinical signs due to variation of routes could be detected. Involvement of brain with io route could be detected even in preclinical stage. Although the virus could be detected in the postclinical stage in all the tissues under study (brain, skin, salivary gland and corneal impression), with io and ic routes spread of the virus was observed in comparatively higher concentrations.

The effect of music on ketamine induced emergence phenomena

The purpose of this investigation was to assess the influence of music on emergence phenomena after ketamine anaesthesia. Fifty ASA 1 patients undergoing minor gynaecological procedures were randomly divided into two equal groups. Patients in the treated group were played music of their choice through headphones from 5 min before induction of anaesthesia to 15 min postoperatively. Although the incidence of emergence phenomena was similar in both groups the effects tended to be more pleasant and acceptable in those to whom music was played. The majority of patients in the study group (80%) expressed their willingness to have a similar anaesthetic in the future compared to 52% in the control group (p less than 0.05).

Developmentally regulated male-specific transfactor(s) enable in vitro transcription of a cloned alpha 2u-globulin gene

Selected members of the rat alpha 2u-globulin gene family are expressed in several tissues, manifesting characteristic developmental and endocrine transcriptional control. Studies are now underway to identify the responsible cis sequences and transacting factors. We recently reported that the cloned rat alpha 2u-globulin 207 gene manifests tissue-specific androgen-dependent expression; it is expressed in livers of male, but not female, transgenic mice. In the present study a portion of this gene (-639 to +1395) is used as an in vitro template in the presence of nuclear extracts derived from hepatic nuclei of prepubescent and mature male and female rats. alpha-Amanitin-sensitive in vitro transcription of the alpha 2u 207 gene by extracts derived from mature male rats is highly active and is at least 13 times as rapid as that with preparations from mature female or immature animals. In contrast, the rate of transcription of a control template, the adenoviral late promoter, is the same with all of these nuclear extracts. S1 nuclease analysis and the size of the transcript indicate that transcription is initiated in vitro at the same site as it is in vivo and that it continues to the 3' terminus of the alpha 2u-globulin template. Thus, cis sequences are present in this gene fragment which are controlled by developmentally regulated male transacting factors, enabling selective transcription of this alpha 2u-globulin gene. Mixing experiments indicate that this transcriptional control is positive.

Nucleotide sequence of a major class-III phage-T3 RNA-polymerase promoter located at 98.0% of phage-T3 genetic map

The entire nucleotide sequence of a 409-bp HincII fragment, located within the MboI-E fragment on bacteriophage T3 DNA and containing a major class-III T3 RNA polymerase promoter positioned at 98% on the standard T3 genetic map, has been determined. Alignment of this class-III promoter with previously determined T3 RNA polymerase promoters, with start points of transcription (+1) in register, indicates high degree of sequence conservation between position -16 to +6 among all T3 RNA polymerase promoters. The conserved portion of the (-) strand sequence is 5'-A-TA-T-AT-A-C-C-C-T-C-A-C-T-A-A-A-G-G-G-A---3'. This fragment also contains an open reading frame (ORF) with a translational start codon located at position +146 which is preceded by a potential ribosome binding site (RBS). There is more than 70% amino acid-sequence homology between the deduced sequences of the -NH2 terminal region of this putative T3 phage protein and the corresponding protein coded by bacteriophage T7 (protein of T7 gene 19.5).

Locations and nucleotide sequences of three major class III promoters for bacteriophage T3 RNA polymerase on T3 DNA

The DNA sequences of three major class III T3 RNA polymerase promoters located at 45.0, 55.0, and 64.8% on the standard T3 genetic map have been determined. The precise RNA initiation sites were also determined by 5'-terminal RNA sequence analysis of the transcripts synthesized from the promoter-containing DNA fragments. Alignment of these three class III promoters and a previously determined T3 RNA polymerase promoter at 1.05% on T3 genetic map, with start points of transcription (+1) in register, indicates a high degree of sequence conservation among the four T3 RNA polymerase promoters. The sequences are identical between positions -12 and +4 and are uniformly A-T between -12 and -17. The conserved portion of the (-) strand sequence is 5' (sequence in text) Upstream from -17 and downstream from +4 the sequences diverge. Comparison of this sequence with a prototype 23-base pair promoter sequence for T7 RNA polymerase shows overall homology between positions -17 and +4 with conserved divergence at residues -2 and between -10 and -12. Furthermore, careful examination of the nucleotide sequences around 45.0 and 64.8 T3 map units shows that the putative RNA sequences arising from these regions by overlapping transcription from upstream promoters can be arranged into stable stemloop structures thought to be required for RNase III cleavage. This pattern is similar to those reported for the corresponding T7 RNA polymerase promoters on T7 DNA (Dunn. J. J., and Studier, F. W. (1983) J. Mol. Biol. 166, 477-535).

Bovine retinal pigment epithelial cells cultured in vitro: growth characteristics, morphology, chromosomes, phagocytosis ability, tyrosinase activity and effect of freezing

We compared the bovine melanotic and amelanotic retinal pigment epithelial (RPE) cells cultivated in vitro using a number of parameters. Both cell types could be readily harvested from the eye by dissection or by enzyme treatment of the RPE. Both types of cells grew equally well in the primary culture, and in serial subcultures for over 600 days, and also after being stored frozen for over two months. The two types of cells were similar in their growth patterns, morphology, chromosome characteristics and phagocytic activity but they differed in their tyrosinase activity. Although in long-term cultures cells showed chromosome loss, a high proportion of the cells retained their normal diploid chromosome number (2n = 60) with apparently normal karyotype.

Location, function, and nucleotide sequence of a promoter for bacteriophage T3 RNA polymerase

The major promoters for bacteriophage T3 RNA polymerase on the T3 genome have been mapped by DNA.RNA filter hybridization. One promoter is located in a 300-base-pair Hpa I restriction fragment near the genetic "left" end of T3 DNA. The sequence in the vicinity of the major initiation site of transcription in this region has been determined. A part of the (-)strand sequence is 5' T-A-T-T-T-A-C-C-C-T-C-A-C-T-A-A-A-G-+1 G-G-A-A-U 3'. Comparison of this sequence with the prototype 23-base-pair promoter sequence for bacteriophage T7 RNA polymerase shows a striking pattern of homology and divergence. Between positions -9 and +4, the sequences are virtually identical, whereas between positions -17 and -10, the sequences are quite different. It is postulated that these sequence subsets may perform different functions in transcription initiation by the phage RNA polymerases.

Construction of a restriction map of bacteriophage T3 DNA

A restriction endonuclease cleavage map of bacteriophage T3 DNA has been constructed. The enzymes used and, within parentheses, the number of their cleavage sites on T3 DNA are: HindIII (1), XbaI (1), BglII (1), KpnI (2), MboI (9), and HpaI (17). The size and the relative location of each fragment have been established, defining an accurate physical map of T3 DNA.