Absence of genetic heterogeneity in Duchenne muscular dystrophy shown by a linkage study using two cloned DNA sequences

A linkage study using two different restriction fragment length polymorphisms (RFLPs) identified with cloned DNA sequences has failed to provide evidence for genetic heterogeneity in Duchenne muscular dystrophy (DMD) when tested against intelligence quotient (IQ). Analysis of data for age of confinement to a wheelchair against IQ gave no evidence for heterogeneity. These results are of a practical as well as theoretical significance, since the existence of multiple loci causing DMD would make it more difficult to apply linkage data to genotype prediction in this disease.

Recognition and regulation of progenitor marrow elements by NK cells in the mouse

The cytotoxicity of radiolabelled YAC-1 target cells by natural killer (NK) cells from the spleens of immunocompetent CBA mice is inhibited by unlabelled YAC-1 competitor cells, but not by resting bone marrow from syngeneic or allogeneic adult mice. Rapidly proliferating haemopoietic cells recovered from the spleens of lethally irradiated, bone marrow-reconstituted CBA mice, however, compete strongly in the NK assay. The competitive ability of early regenerating marrow correlates with the presence of an increased percentage of morphologically immature cells of mixed lineages. Competition declines in reconstituted spleens recovered more than 10 days after engraftment, as the proportion of immature elements falls towards that of resting marrow. Although the numbers of unlabelled YAC-1 cells required to produce equivalent competition of unstimulated and interferon-activated NK killing are similar, 10 times fewer regenerating marrow competitors compete cytotoxicity by unstimulated NK effectors to the same degree as interferon activated cells. The numbers of granulocyte-macrophage colonies formed in soft agar by regenerating marrow is also influenced by prior incubation of the marrow cells with NK effector populations. Spleen cells from homozygous athymic mice produce the same effect as cells from their heterozygous littermates. These data suggest that NK cells recognize and regulate the differentiation of progenitor elements within the marrow.

Blood pressure and myotonic dystrophy

The blood pressures of 79 consecutive patients with myotonic dystrophy have been shown to be significantly lower than those of a control series. Reanalysis of previously published data on a group of 17 myotonic dystrophy patients shows a similar result. The possibility that relative hypotension may confer a selective genetic advantage on asymptomatic gene carriers in the community is considered. It is suggested that, since patients with minimal clinical evidence of disease are also hypotensive, measurement of blood pressure may be useful as an adjunct to other methods of preclinical diagnosis of myotonic dystrophy.

Genetic linkage between the loci for myotonic dystrophy and peptidase D

In a linkage study between myotonic dystrophy and peptidase D it is evident from the lod score values that with high probability theta lies between 0 and 0.1. The data thus support a previous hint of linkage between peptidase D and the Lutheran and secretor loci, which were already known to be linked to myotonic dystrophy.

Linkage analysis of two cloned DNA sequences flanking the Duchenne muscular dystrophy locus on the short arm of the human X chromosome

The inheritance of two restriction fragment length polymorphisms (RFLPs) on the short arm of the human X chromosome has been studied relative to Duchenne muscular dystrophy. This provides a partial genetic map of the short arm of the human X chromosome between Xp110 and Xp223. The data were derived from the segregation between a RFLP located at Xp21-Xp223, the DMD locus, and a RFLP located at Xp110-Xp113. The genetic distance from Xp110 to Xp223 was found to be approximately 40 centimorgans (cM). This provides experimental confirmation that 1cM corresponds to approximately 1,000 kilobase pairs of DNA for this region of the human X chromosome. Our data confirm that the DMD mutation lies between Xp223 and Xp110. The availability of flanking probes surrounding the DMD locus will assist in the ordering of further DNA sequences relative to the mutation.

Acute haematogenous osteomyelitis

Seventy-seven children admitted with a provisional diagnosis of acute osteomyelitis over a three year period have been reviewed. Acute haematogenous osteomyelitis was confirmed in 45 of these patients whose ages varied from three days to 14 years with a mean of 6.2 years. All patients were treated with intravenous fusidic acid and cloxacillin with splintage for three weeks followed by oral antibiotics for a further period of six weeks. Only seven patients required operation. One patient had recurrence of infection; all other patients were cured with no evidence of chronic osteomyelitis. It is suggested that surgical drainage of acute haematogenous osteomyelitis is seldom needed and that high intravenous doses of antibiotics in combination with splintage are adequate treatment in most cases.

The detection of estrogen receptors in gynecologic tumors using immunoperoxidase and the dextran-coated charcoal assay

The dextran-coated charcoal receptor assay for demonstrating functional estrogen and progesterone receptors was used to evaluate the receptor content of gynecological tumors. An immunocytochemical method, the immunoperoxidase antiperoxidase method, that may detect estrogen receptors, was also employed on the same specimens utilizing sections from formalin-fixed paraffin embedded blocks. The results by the two methods were compared and were correlated with the state of differentiation of the tumors. According to the dextran-coated charcoal method, two cases of well differentiated endometrial adenocarcinoma were strongly positive for both estradiol and progesterone receptors, and three moderately differentiated cases contained lesser amounts of both types of receptors. Six cases of undifferentiated adenocarcinoma ranged from no detectable receptors to very high values, while of five cases of squamous cell carcinoma of the cervix, only two were positive for estradiol receptors by the dextran-coated charcoal method. Staining of tissue sections from these same cases using the immunoperoxidase method, demonstrated a positive correlation to the dextran-coated charcoal assay for estrogen receptors. The Dextran-coated charcoal method is presently being used clinically as a screening measure for statistical probability of a patient's response to hormone therapy. The degree of positive correlation shown here suggests that use of the immunoperoxidase method may have further potential for diagnostic and clinical use, and merits further investigation.

Gas-liquid chromatographic-thermal energy analyzer determination of N-nitrosodimethylamine in beer: collaborative study

The GLC/TEA method for N-nitrosodimethylamine (NDMA) in beer was studied collaboratively by 13 laboratories from 7 countries. Collaborators were asked to analyze a total of 10 randomly labeled samples of beer consisting of the following duplicates: a naturally contaminated commercial beer; a beer extremely low (ca 0.1 ppb) in NDMA; and the low NDMA beer spiked with 0.5, 1.9, and 5.0 ppb NDMA. The pooled repeatability and reproducibility coefficients of variation (CV) for all samples were 17% and 27%, respectively. However, when data from 2 laboratories (outliers) were omitted, the corresponding CV values improved considerably (11% and 15%, respectively). Variance analysis showed the presence of a significant laboratory-sample interaction when all data were used for analysis, but this interaction disappeared when data from the 2 outlying laboratories were excluded. The pooled percent recovery of the overall method (omitting outliers) was 101.4 +/- 3.5. All the laboratories detected NDMA in the low NDMA beer. The method was adopted official first action.

Prognosis of convulsions between 1 and 6 months of age

The prognosis of 28 infants presenting consecutively to a general paediatric unit with convulsions between 1 and 6 months of age was far better than had been reported previously. Between 1 and 4 years after presentation the condition of 19 patients was normal, 3 were mildly handicapped, 4 severely handicapped, and 2 had died. Normal physical examination and electroencephalogram at time of presentation, and easy control of convulsions were associated with a satisfactory outcome.

Elevation of voice volume in young developmentally delayed children via an operant shaping procedure

Unusually low voice volume was identified by teachers as a significant impediment to the academic and social progress of two preschool students. A simple operant shaping procedure was conducted by teachers to increase voice volume using a voice-activated apparatus with attractive visual display. Setting generalization of volume increases to the classroom was achieved and maintained at one- and four-month follow-ups.

Effects of hyperthermia on normal and tumor microenvironment

The effects of hyperthermia on pH, local blood flow (LBF) and tissue oxygen tension (TpO2) in several normal and tumor tissues were studied. It was found that TpO2, local blood flow and pH are inhomogeneous in tumor tissue. TpO2 is very low in certain areas which also seem deprived of blood flow and are at very low pH. Hyperthermia has a dual effect: at temperatures below 41 degrees C, it increases blood flow and TpO2 while above 41 degrees C, it causes a collapse in blood flow, lower TpO2 and a shift of the tissue pH towards acidosis from the already low pH values found in tumors.

Feline chronic progressive polyarthritis

Twenty cats with a chronic progressive polyarthritis were studied. The disorder occurred exclusively in male cats, and all but six of the cats were between 1.5 and 5.0 years of age. There were two forms of the disease as determined by radiographic changes: joint instability and deformity, and clinical course. The most prevalent form of the disease was characterized by osteopenia and periosteal new bone formation surrounding affected joints. Marginal periarticular erosions and collapse of the joint spaces with fibrous ankylosis occurred with time, but joint instability and deformities were not seen. The second form of the disease was characterized by severe subchondral marginal erosions, joint instability, and deformities. The periosteal proliferative form resembled Reiter's arthritis of man, and the deforming type resembled human rheumatoid arthritis. The disease began as tenosynovitis and synovitis, with subsequent changes in the articular cartilage and periosteal bone. Histopathologic changes in these cats were similar to those occurring in both chronic Reiter's and rheumatoid arthritis of man. Chronic progressive polyarthritis of cats was not caused by identifiable bacteria or mycoplasma, but was etiologically linked to feline leukemia virus (FeLV) and feline syncytia-forming virus (FeSFV) infections. The FeSFV was isolated from the blood or was detected by a serologic test in all of the cats with the disease, whereas FeLV was isolated or identified by immunofluorescence technique in 60% of the cats. The arthritis could not be reproduced by inoculation of cell-free cynovial tissue from diseased cats or with tissue culture fluid containing FeSFV and FeLV isolates. It was postulated that arthritis was an uncommon manifestation of FeSFV infection that occurred in predisposed male cats. Feline leukemia virus may not have been directly involved in the disease, but may have acted in some way to potentiate the pathogenic effects of FeSFV.

Rapid photomodulation of stem extension in light-grownSinapis alba L. : Studies on kinetics, site of perception and photoreceptor

Treatment of the whole of aSinapis alba plant with supplementary far-red light (FR), in back-ground white light (WL), induces a rapid increase in stem extension rate. This rapid increase is regulated by the light environment of the stem itself. Supplementary FR to the stem increases extension rate after a lag period of 10-15 min. A lag period of 3-4 h follows FR irradiation of the leaf, before an increase in extension rate is detectable. When the stem is given supplementary FR, the change in extension rate which is induced increases with increasing FR fluence rate, and with decreasing phytochrome photoequilibrium. There is no difference between the effects of supplementary FR λmax 719 nm and supplementary FR λmax 739 nm for these relationships. The increase in extension rate induced by supplementary FR is reversed by an increase in the fluence rate of red light (R). These data indicate that the response is controlled by phytochrome photoequilibrium.

Prepartum serum hormone concentrations related to dystocia in Holstein heifers

Twelve Holstein heifers from a herd having a high incidence of dystocia were bled each day at 0730 h from 260 days gestation until parturition. The blood was analyzed for estradiol-17beta, estrone, 17-hydroxyprogesterone, progesterone, and corticosteroids. Six of the animals had dystocia. The concentrations of estradiol-17beta were lower and the concentration of progesterone higher in dystocial animals during the prepartum period from 23 to 12 days. The prepartum patterns of secretion of corticosteroid, estrone, and 17-hydroxyprogesterone did not change significantly in the two groups between days 23 and 12 prepartum. The prepartum difference in serum estradiol-17beta and progesterone concentration between normal and dystocial animals suggests that the timing of hormone changes in preparation for parturition is delayed and not as pronounced in dystocial animals.

Variables influencing "lining up the shot" in golf putting

A laboratory program for the study of golf-putting skills is described. A brief description of the method and apparatus is followed by a general presentation of experimental results which helped determine the technique now in use.