Chromosome breakage and rejoining of sister chromatids in Bloom's syndrome

The occurrence of chromosome breaks and reunion of sister chromatids in lymphocytes of two patients with Bloom's syndrome has been compared with those found in X-rayed and control cells. The distribution of breaks in BS is non-random both between and within chromosomes, the centric regions of certain chromosomes being preferentially involved. The following working hypotheses are put forward: When chromosome breaks in human lymphocytes occur in G₀— G₁, practically no sister chromatid reunion (SCR) takes place, whereas ends created by an S—G₂ break show a considerable tendency to SCR. We propose further that chromosome aberrations in BS mainly result from breaks in S—G₂, including possible U-type rejoining of sister chromatid exchanges. Fragments extra to an intact chromosome complement result from a chromatid break or an asymmetrical chromatid translocation in a previous mitosis.     

The pyrogenic effect of scarlet fever toxin

Scarlet fever toxin was found to liberate leukocytic pyrogen from granulocytesin vitro. In comparative experiments withSalmonella paratyphi B endotoxin and scarlet fever toxin it was tested whether leukocytes from rabbits tolerant to one of these toxins are able to synthetize and liberate endogenous pyrogen. Leukocytes from rabbits tolerant to endotoxin liberated leukoeytic pyrogen following challenge with endotoxin or with scarlet fever toxin. Leukocytes from animals tolerant to scarlet fever toxin liberated leukocytic pyrogen in the presence of endotoxin, but were insensitive to homologous, i.e. scarlet fever toxin. Similarly, leukocytes from cortisone-treated animals did not liberate leukocytic pyrogen if they were incubated with scarlet fever toxin, but liberation of leukocytic pyrogen did take place under challenge with endotoxin. Leukocytes from normal animals incubated in Hanks solution without toxin did not synthetize endogenous pyrogen.     

The stage of chromosome duplication in the cell cycle as revealed by X-ray breakage and 3H-thymidine labeling

By means of combined experiments of X-irradiation and ³H-thymidine labeling of the chromosomes which are in the phase of synthesis, and the subsequent analysis at metaphase on the autoradiographs of the chromosomal damage induced during interphase, it was shown that in somatic cells from a quasi-diploid Chinese hamster line cultured in vitro the chromosomes change their response to radiation from single (chromosome type aberrations) to double (chromatid type aberrations) in late G₁. These results are interpreted to indicate that the chromosome splits into two chromatids in G₁, before DNA replication. — By extending the observations at the second metaphase after irradiation, it was also seen that cells irradiated while in G₂ or late S when they reach the second post-irradiation mitosis still exhibit, beside chromosome type aberrations, many chromatid exchanges, some of which are labeled. Two hypotheses are suggested to account for this unexpected reappearance of chromatid aberrations at the second post-irradiation division. The first hypothesis is that they arise from half-chromatid aberrations. The second hypothesis, which derives from a new interpretation of the mechanisms of production of chromosome aberrations recently forwarded by Evans, is that they arise from gaps or achromatic lesions which undergo, as the cells go through the next cycle, a two-step repair process culminating in the production of aberrations.This work was supported in part by grant No. RH-00304 from the Division of Radiological Health, Bureau of State Services, Public Health Service, U.S.A.     

Rash Associated with Coxsackie A9 Infection

Coxsackie A9 virus was identified by the authors during the fall of 1965 in Montreal in six children with fever and exanthem. Three of the six children were siblings. The exanthem was centrally distributed as described by Lerner et al. and consisted of discrete maculopapules 3 to 4 mm. in diameter. The viral agent was recovered and identified in tissue culture in five cases, while in the sixth Coxsackie type-A lesions were produced in suckling mice. Serological confirmation was obtained in two patients from whom sera were available. In contrast, no exanthem was observed in three older patients with a diagnosis of aseptic meningitis associated with Coxsackie A9 virus. In only one of 16 patients with Coxsackie B virus infection was an exanthem observed during the same period.The true incidence of Coxsackie A9-associated exanthems is difficult to determine because of the benign nature of the disease.     

Association of the shuffling of Streptococcus pyogenes clones and the fluctuation of scarlet fever cases between 2000 and 2006 in central Taiwan

Background  

The number of scarlet fever occurrences reported between 2000 and 2006 fluctuated considerably in central Taiwan and throughout the nation. Isolates of Streptococcus pyogenes were collected from scarlet fever patients in central Taiwan and were characterized by emm sequencing and a standardized pulsed-field gel electrophoresis (PFGE) method. National weekly report data were collected for investigating epidemiological trends.     

Analysis of a BrdU-sensitive site in the cactus mouse (Peromyscus eremicus): chromosomal breakage and sister-chromatid exchange

When the thymidine analog BrdU was incorporated into the DNA of a fibroblast cell line derived from the cactus mouse Peromyscus eremicus, a chromosome region with an increased frequency of gaps and breaks was observed. Nearly a third of the chromatid aberrations found at this site were associated with a sister-chromatid exchange (SCE) although this chromosome region showed no increase in sister-chromatid exchange in the absence of a gap or break. SCEs were significantly decreased in the remainder of the chromosome arm when it contained an aberration at the unstable site. This BrdU-sensitive region, unlike others reported, was found not to be late-replicating. — In this chromosome complement, the frequency of sisterchromatid exchange in C-band positive regions was significantly lower than that in C-band negative regions.     

Sporadic Occurrence of Echo Virus Types 27 and 31 Associated with Aseptic Meningitis in Ontario

The sporadic occurrence of Echo virus types 27 and 31 in association with aseptic meningitis during the enterovirus seasons in Ontario in 1959 to 1962 is reported.The etiological significance of both of these isolates was verified by demonstration of type-specific serological response in meningitis patients. Echo 27, which up to now has not been encountered in association with human illness, could be added to the list of viral agents capable of causing aseptic meningitis. Isolation of Echo 31 from cerebrospinal fluid provides definite proof of the etiological significance of this virus in cases of aseptic meningitis.     

Adenine Nucleotide Hydrolysis in Patients with Aseptic and Bacterial Meningitis

The meningitis is a disease with high mortality rates capable to cause neurologic sequelae. The adenosine (the final product of ATP hydrolysis by ectonucleotidases), have a recognized neuroprotective actions in the central nervous system (CNS) in pathological conditions. The aim of the present study was evaluate the adenine nucleotides hydrolysis for to verify one possible role of ATP, ADP and AMP hydrolysis in inflammatory process such as meningitis. The hydrolysis was verified in cerebrospinal fluid (CSF) from human patients with aseptic and bacterial meningitis. Our results showed that the ATP hydrolysis was reduced 12.28% (P < 0.05) in bacterial meningitis and 22% (P < 0.05) in aseptic meningitis. ADP and AMP hydrolysis increased 79.13% (P < 0.05) and 26.37% (P < 0.05) in bacterial meningitis, respectively, and 57.39% (P < 0.05) and 42.64% (P < 0.05) in aseptic meningitis, respectively. This may be an important protective mechanism in order to increase adenosine production.     

Aseptic meningitis,Montreal, 1969: A Clinical and Laboratory Study

During the summer and fall of 1969 an outbreak of aseptic meningitis occurred in Montreal and its environs. Forty-four patients were admitted to the infectious disease ward of The Montreal Children''s Hospital in August, September and October. Half of the patients were in the age group 6 to 10 years. The ratio of males to females was two to one. Patients showed the typical signs and symptoms of aseptic meningitis, namely fever, vomiting, headache, neck stiffness and pleocytosis of the cerebrospinal fluid.Viruses were recovered from 19 (43%) of the 44 cases. The predominant virus in the outbreak was a non-hemagglutinating strain of echovirus 6. Other virus types isolated in the outbreak were echovirus 7, coxsackievirus A9 and coxsackievirus B4. Serological investigations confirmed the validity of the echovirus isolations and identified additional cases.     

Oxidative stress in childhood meningitis: measurement of 8-hydroxy-2'-deoxyguanosine concentration in cerebrospinal fluid

Abstract

To examine the involvement of reactive oxygen species, we measured the concentration of 8-hydroxy-2′-deoxyguanosine (8-OHdG), a biomarker of oxidative stress, in cerebrospinal fluid samples from 63 children with and without meningitis. We observed that the mean concentration of 8-OHdG in samples obtained during the early phase of bacterial meningitis, but not aseptic meningitis, was significantly higher than that in control samples. Clinical and laboratory improvement was associated with a fall in the 8-OHdG concentration in the patients with bacterial meningitis. Our findings suggest the presence of enhanced oxidative stress in the central nervous system of children with bacterial meningitis.     

Die Zuordnung des Locus R der Zuckerrübe (Hypokotylfarbe) zum Chromosom II

Zusammenfassung Mit Hilfe von Trisomen wurde am Locus R (Hypokotylfarbe) gezeigt, daß die Koppelungsgruppe, die R, B (Schossen ohne Vernalisation) und andere bekannte Loci enthält, im Chromosom II (Numerierung nachButterfass 1964) liegt. Ob Chromatidenspaltung im Locus R eine Rolle spielt, konnte nicht sicher festgestellt werden.

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The coordination of the locus R (hypocotyl colour) of sugar beet to chromosome II

Summary By means of trisomics the linkage group containing R (hypocotyl colour), B (bolting without vernalization) and other known loci was shown to lie in chromosome II (numbering afterButterfass 1964). Whether random chromatid assortment in R is involved could not be established with certainty.

     

Viral Infections of Toronto Children During 1965: I. Enteroviral Disease

Enteroviruses were isolated from feces and/or cerebrospinal fluid of 29 of 43 Toronto children who contracted aseptic meningitis, pleurodynia, abdominal pain or febrile upsets between June and October, 1965. Coxsackie A9 virus was the dominant agent in aseptic meningitis and Coxsackie B1 virus in pleurodynia and other syndromes. Sero-logical evidence of recent Coxsackie B1 and Echo 6 infection was obtained in two additional patients with aseptic meningitis who did not yield virus, and elevated Coxsackie B1 antibody titres were found in one patient with pericarditis. A newborn infant died with myocarditis due to Coxsackie B1 virus following infection of the mother during the immediate antenatal period. Paired sera collected only two to four days apart from patients with enteroviral syndromes or mumps meningoencephalitis frequently showed four-fold or greater increases of antibody levels.     

Enteroviral and Mumps Meningitis in Toronto, 1963

Virological investigations of 115 children with the aseptic meningitis syndrome during 1963 resulted in the isolation of enteroviruses from cerebrospinal fluid (CSF) and/or feces of 21 of 48 children who had no association with mumps. For the third successive year, Echo 9 was the dominant enterovirus in cases of aseptic meningitis in Toronto children, but no rashes were associated with Echo 9 meningitis during 1963, in contradistinction to previous years. Mumps virus was isolated from CSF of 25 patients by inoculation of rhesus monkey kidney cultures, and rising or elevated mumps antihemagglutinin titres in paired sera from a further 33 cases provided laboratory evidence of infection with mumps virus in 58 of 67 patients with mumps meningoencephalitis. No enlargement of salivary glands was noted in 20 laboratory-proved cases of mumps meningoencephalitis. Enteroviral meningitis occurred principally during summer, but the peak of mumps meningoencephalitis occurred during late winter.     

Oxidative Stress in Cerebrospinal Fluid of Patients with Aseptic and Bacterial Meningitis

This study aimed to determine whether patients with aseptic and bacterial meningitis presented alterations in oxidative stress parameters of cerebrospinal fluid (CSF). A total of 30 patients were used in the research. The CSF oxidative stress status has been evaluated through many parameters, such as lipid peroxidation through thiobarbituric acid reactive substances (TBARS) and antioxidant defense systems such as superoxide dismutase (SOD), glutathione S-transferase (GST), reduced glutathione (GSH) and ascorbic acid. TBARS levels, SOD and GST activity increase in aseptic meningitis and in bacterial meningitis. The ascorbic acid concentration increased significantly in patients with both meningitis types. The reduced glutathione levels were reduced in CSF of patients with aseptic and bacterial meningitis. In present study we may conclude that oxidative stress contributes at least in part to the severe neurological dysfunction found in meningitis.     

An Outbreak of Aseptic Meningitis due to Echo 25 Virus

In a widespread outbreak of aseptic meningitis during the summer and early fall of 1961 in Ontario, Echo type 25 virus was found to be the predominant virus type isolated from affected patients. Recovery of Echo 25 virus in several cases from the CSF of patients strongly suggests an etiological relationship between this virus type and the illness. The causative role of the virus was confirmed by demonstration of significant immunological response in patients found to be infected with the virus. The presence of antibodies to Echo 25 virus in about 70% of meningitis patients, from whom no virus was isolated, indicates that the infection in the population of the affected areas was much more prevalent than the number of successful virus isolations would suggest. It is recommended that Echo 25 virus should be added to the series of Echo virus types capable of causing outbreaks of aseptic meningitis.     

Structural analysis of heavy ion radiation-induced chromosome aberrations by atomic force microscopy

Heavy ion radiation (high linear energy transfer, LET, radiation) induces various types of chromosome aberration. In this report, we describe a new method employing an atomic force microscope (AFM) for nanometer-level structural analysis of chromosome damage induced by heavy ion irradiation. Metaphase mouse chromosomes with chromatid gap or chromatid breaks induced by heavy ion irradiation were marked under a light microscope. Then the detailed structure of chromosomes of Giemsa-stained or unstained samples was visualized by the AFM. The height data of chromosomes obtained by AFM provided useful information to distinguish chromatid gaps and breaks. A fibrous structure was observed on the unstained chromosome, the average width of which was about 45.8 nm in the image of AFM. These structures were considered to be 30-nm fibers on the chromosome. The structure of the break point regions induced by neon- or carbon-ion irradiation was imaged by AFM. In some cases, the fibrous structure of break points was detected by AFM imaging after carbon ion irradiation. These observations indicated that AFM is a useful tool for analysis of chromosome aberrations induced by heavy ion radiation.     

Fucosyltransferase expression in human platelets and leucocytes

The activities of -2-l-fucosyltransferase and -3-l-fucosyltransferase were measured in human platelets and leucocytes from normal donors, -2-l-Fucosyltransferase was found in platelets but not in leucocytes. In contrast -3-l-fucosyltransferase was not detected in platelets but was present in leucocytes where it was demonstrated in the neutrophil, monocyte and lymphocyte fractions.     

Neurotensin-like immunoreactivity (NTLI) concentration in the cerebrospinal fluid of children and its alteration in a febrile aseptic meningitis

Neurotensin-like immunoreactivity (NTLI) concentrations in the cerebrospinal fluid (CSF) of normal children and patients with febrile aseptic meningitis, aged 7 months to 15 years, were studied. The NTLI concentrations in CSF of 27 children with normal CSF findings were 160.1 +/- 54.6 pg/ml (mean +/- S.D.). The NTLI concentration in CSF of 26 patients in an acute phase of aseptic meningitis was 110.6 +/- 51.1 pg/ml which was significantly (P less than 0.01) lower than the controls. These patients had a mean temperature of 101.4 +/- 1.5 degrees F which remained elevated for an average of 3.5 days. The NTLI concentrations in CSF of 23 patients in a recovery phase (after blood and CSF findings became normal with no fever) were 166.5 +/- 57.8 pg/ml, which did not differ significantly from the normal. There were no statistical correlations between the NTLI concentration in CSF and the protein concentration or total cell count in CSF. These results suggest that NTLI concentration changes during a febrile aseptic meningitis and that it may be associated with thermoregulation.     

A chromosomal study on blood lymphocytes of patients poisoned by polychlorinated biphenyls

Chromosome studies were carried out on peripheral blood lymphocytes from 36 PCB-poisoned patients and on ten PCB-unexposed healthy controls. Nineteen out of 36 patients (52.7%) had either chromosome or chromatid aberrations, while none of the controls had. The highest percentage of cells with chromosome or chromatid aberrations in a single individual was 34.0. The blood PCB level ranged from 6.4 to 101.8 ppb, with a mean of 34.1 ppb. No correlation was observed between the level of blood PCB and the presence or absence of chromosome or chromatid aberrations.     

Aseptic Meningitis due to Frater Type Virus in Ontario

During the summer and fall of 1959 and 1960 a virus was isolated on 14 occasions from the stool or cerebrospinal fluid or both of 12 patients with a clinical picture of non-paralytic poliomyelitis or aseptic meningitis. The patients were from eight different localities in Ontario. The isolated virus was not neutralized by antisera to any of the known enteroviruses, reoviruses or adenoviruses, nor did antiserum to the isolate neutralize any of these viruses. Antiserum to Frater virus, however, did neutralize this isolate and in turn was itself neutralized by antiserum to this virus. Frater virus was isolated in Scotland from cases of aseptic meningitis during the same period in 1959 and 1960. In Ontario this virus was not encountered before 1959. Isolation of the virus from cerebrospinal fluid and demonstration of immunological response in the patients establish its etiological significance. Biological characteristics indicate that it belongs to the Echo group.