Identification of the thymidine kinase gene of feline herpesvirus: use of degenerate oligonucleotides in the polymerase chain reaction to isolate herpesvirus gene homologs.

Feline herpesvirus 1 (FHV) is the causative agent of viral rhinotracheitis in cats. Current vaccination programs employing attenuated live and killed FHV vaccines have been effective in reducing the incidence of this disease. As an initial step in the development of recombinant FHVs for use in the vaccination of cats, we have identified the thymidine kinase (TK) gene of this feline-specific alphaherpesvirus. Comparisons of the amino acid sequences of other herpesvirus TK proteins have shown that these proteins are highly divergent, sharing only short regions of imperfect amino acid identity. We have used the polymerase chain reaction method of DNA amplification to increase the specificity associated with the use of short, highly degenerate oligonucleotide probes derived from regions of imperfect amino acid conservation. These methods were used to isolate the TK gene of FHV and should prove to be useful in the identification of new members of other viral and cellular gene families. A recombinant FHV bearing a deletion in the identified TK gene was constructed and shown to possess the expected TK- phenotype. The FHV TK gene is located at a position of approximately 40% in the long unique component of the FHV genome. The location of the TK gene and the location and orientation of flanking FHV genes, homologs of herpes simplex virus type 1 UL24 and UL22, are conserved among alphaherpesviruses.     

Increased Neural Cell Adhesion Molecule in the CSF of Patients with Mood Disorder

Abstract: Neural cell adhesion molecule (N-CAM) is involved in cell-cell interactions during synaptogenesis, morphogenesis, and plasticity of the nervous system. Disturbances in synaptic restructuring and neural plasticity may be related to the pathogenesis of several neuropsychiatric diseases, including mood disorders and schizophrenia. Disturbances in brain cellular function may alter concentrations of N-CAM in the CSF. Soluble human N-CAM proteins are detectable in the CSF but are minor constituents of serum. We have recently found an increase in N-CAM content in the CSF of patients with schizophrenia. Although the pathogenesis of both schizophrenia and mood disorders is unknown, ventriculomegaly, decreased temporal lobe volume, and subcortical structural abnormalities have been reported for both disorders. We have therefore measured N-CAM concentrations in the CSF of patients with mood disorder. There were significant increases in amounts of N-CAM immunoreactive proteins, primarily the 120-kDa band, in the CSF of psychiatric inpatients with bipolar mood disorder type I and recurrent unipolar major depression. There were no differences in bipolar mood disorder type II patients as compared with normals. There were no significant effects of medication treatment on N-CAM concentrations. It is possible that the 120-kDa N-CAM band present in the CSF is derived from CNS cells as a secreted soluble N-CAM isoform. Our results suggest the possibility of latent state-related disturbances in N-CAM cellular function, i.e., residue from a previous episode, or abnormal N-CAM turnover in the CNS of patients with mood disorder.     

CHARACTERIZATION OF TWO CHLORELLA VULGARIS (CHLOROPHYCEAE) STRAINS ISOLATED FROM WASTEWATER OXIDATION PONDS1

We report here on the characterization and isolation of two ecotypes of Chlorella vulgaris Beyerinck that coexist in wastewater reservoirs. One ecotype (C1) contains high amounts of chlorophyll b, is capable of autotrophic growth, and can utilize only a few organic solutes for growth. The second ecotype (C2) contains low amounts of chlorophyll b, requires vitamin B₁₂, and can support its growth with a broad range of organic compounds. Of the two ecotypes, the latter showed slower growth rates when light was the sole source of energy. Cells of C2-type Chlorella attained higher photosynthetic activities than C1-type cells at saturating irradiances. However, their low chlorophyll b content and lower light utilization efficiency suggest that C2-type Chlorella contains relatively low amounts of light-harvesting antennae, a disadvantage in severely light-limited ecosystems like wastewater reservoirs. We hypothesize that the two Chlorella types coexist by adopting different lifestyles: C1-type cells rely largely on their photosynthetic potential for energy conservation and growth, whereas C2-type cells may exploit their heterotrophic properties for this purpose.     

Psychiatry and ethics: The problematics of respect for religious meanings

Over the past two decades American psychiatrists have had to address the emergence of an increasingly fervent religious pluralism. Particularly in cases of socially controversial new religious movements (NRMs), distressed families have pressured psychiatrists to assess the mental state of recruits to such sects, often labeled cults. At this inevitably acrimonious interface between family values and religious liberties, psychiatrists have for the most part resisted pressures to medicalize religious conversions. This article provides an historical review of American psychiatric response to NRMs with respect to nosology and practice. It introduces this response in the more general context of ethics and the problematics of respect for religious meanings.     

A Study on the Predilection Sites of Trichinella spiralis Muscle Larvae in Experimentally Infected Foxes (Alopex lagopus,Vulpes vulpes)

Studies were carried out on the predilection sites of Trichinella spiralis muscle larvae in experimentally infected arctic foxes (Alopex lagopus) and silver foxes (Vulpes vulpes) reared in cages. The highest number of larvae per gramme tissue was found in the muscles of the legs, eyes, diaphragm, and tongue. The 2 fox species showed no significant differences with regard to predilection sites.     

THE REPLICATION TIME AND PATTERN OF THE LIVER CELL IN THE GROWING RAT

Three-week-old male rats of the Wistar strain were given tritiated thymidine, 1 µc/gm body weight, intraperitoneally and were killed at intervals from 0.25 to 72 hours later. Autoradiographs were made from 5 µ sections, stained by the Feulgen method. The replication time and its component intervals were determined from the scoring of the labeling of interphase nuclei as well as of prophase, metaphase, anaphase, and telophase nuclei. Absorption of the intraperitoneally injected label is rapid and is attended by "flash" labeling during interphase. The results show that at any one time about 4 per cent of the liver cells are synthesizing DNA preliminary to cell division. These cells alternate with waves of other cells and it is estimated that about 10 per cent of the liver cell population is engaged in cell duplication. The replication time is about 21.5 hours, and its component intervals occupy the following times: DNA synthesis, 9 hours; post-DNA synthesis gap, 0.50 hour; prophase, 1.3 hours; metaphase, 1.0 hour; anaphase, 0.4 hour; telophase, 0.3 hour; postmitosis gap, 9.0 hours. A group of liver cells has been recorded in at least 3 successive replication cycles.