The age-sex structure of the slave population in Harris County, Texas: 1850 and 1860

The effect of the slave system on demography can be revealed by examining the age-sex structure of slave populations. The age-sex structure of slaves in Harris County, Texas is investigated using the 1850 and 1860 slave schedules. Median ages for black and mulatto slaves suggest that the population was young. Population pyramids exhibit a narrow base and top with a broad middle. The high proportion of slaves between 10 and 30 years of age and the increase in population size between 1850 and 1860 were mainly related to the importation of slaves and only partly due to natural increase. The data also show that black slaves were older on small plantations while mulattoes were older on larger farms. It is suggested that differential treatment in terms of purchase practices, assignment of tasks, food allocation, and/or differential susceptibility to infectious diseases may account for this pattern.

Cardiac tamponade resulting from massive chylopericardium after an aorta-coronary bypass operation

Isolated chylopericardium after a cardiac operation is a rare clinical entity. A case of isolated chylopericardium with cardiac tamponade after a single aorta-coronary artery bypass graft in a 49-year-old man is presented. Nonsurgical management was unsuccessful. Multiple surgical procedures were necessary for complete control of this difficult problem. The cause of chylopericardium in this patient appears to have been injury to the tributaries of lymphatic ducts in the pericardium.

Family resemblance for anthropometric and blood pressure measurements in Black Caribs and Creoles from St. Vincent Island

This paper examines family resemblance for five anthropometric measurements (height, weight, triceps skinfold, upper arm circumference relaxed [UACR] and flexed [UACF] and for systolic and diastolic blood pressure in a group of adult Caribbean islanders of primarily African ancestry. Six hypotheses about family resemblance are tested by using path analysis and likelihood ratios. Significant intergenerational transmission is found only for height and UACR. For weight, UACF, and diastolic blood pressure, non-transmissible sibling resemblance is the primary component of family resemblance, although significant marital resemblance exists for diastolic blood pressure. Triceps skinfold and systolic blood pressure show no evidence of any family resemblance. Although results for highly heritable traits such as height are comparable to reports from other populations, measurements with a large contribution from common family environment or residual environmental effects, such as triceps skinfold or blood pressure, have much lower family resemblance in this population than in other populations. We hypothesize that this difference is due to the fact that adult children and their parents do not share a common household in this culture and to the presence of major nonfamilial environmental factors contributing to obesity and hypertension in this population.

Retrospective DNA analysis of head and neck squamous cell carcinoma

Abnormal cellular DNA content, a hallmark of malignancy, is known to occur in squamous cell carcinoma of the head and neck. The significance of this finding has yet to be elucidated. Paraffin-embedded blocks from 46 squamous cell carcinomas of the head and neck were sectioned, dewaxed, and made into a suspension of bare nuclei by mechanical mincing and enzymatic digestion. The nuclei were stained with propidium iodide, and quantitative DNA measurements were obtained with flow cytometry. The results were compared with existing prognostic factors: DNA aneuploidy was identified in 41% of the specimens and was significantly correlated with tumor size and surgical stage; the relationship between DNA aneuploidy and anatomic site approaches statistical significance. There was no correlation with histologic grade or presence or absence of cervical metastasis.

Association between stress and blood pressure variation in a Caribbean population

Based on the work of Selye (The Stress of Life, New York: McGraw-Hill, 1976) it is hypothesized that stress can produce physiological abnormalities, i.e., elevated blood pressure, and that social variables can be used as indicators or risk factors for disease. It is theorized that deviations from acceptable social patterns or traditional life-styles can produce stressful conditions that are associated with disease and that these situations can be demonstrated by examination of certain social characteristics. This association is examined among the Black Caribs of St. Vincent, West Indies. The social variables included in this analysis are marital status (single, married, widowed, or separated), frequency of church attendance (frequently, sometimes, seldom, or never), years of education, and number of children (for women only). The findings show that single individuals have higher pressures than married subjects and that males who never attend church have higher pressures than men who frequently attend church; a relationship was not demonstrated for females. Among males, as the years of education increased, blood pressure also increased, but for females, increased education was associated with lower pressures. Family size was not associated with systolic or diastolic pressure. The analysis of these selected social variables suggests that these variables influence male systolic and diastolic pressures, but only female diastolic pressure.

Syndrome of short stature, microcephaly, mental retardation, and multiple epiphyseal dysplasia--Lowry-Wood syndrome

We describe a brother and a sister with a syndrome of short stature, microcephaly, mental retardation, and multiple epiphyseal dysplasia. The parents were normal. This appears to be the second example of the syndrome first described by Lowry and Wood [1975] in two boys who had epiphyseal dysplasia, short stature, microcephaly, and nystagmus; one of these patients was mildly mentally retarded. The Lowry-Wood syndrome probably is an autosomal recessive trait.

Relationship between African admixture and blood pressure variation in the Caribbean

The genetic contribution to blood pressure variance is examined by studying a selected group of genes. Of 368 individuals, 48.1% received one-half or more of their genes from an African ancestor and of this group 18.1 and 17.0% exhibit systolic and diastolic hypertension, respectively. A chi-square test was used to examine the dependence of blood pressure on percentage African ancestry. The chi-square values were not significant for systolic or diastolic pressures. It is likely that other factors are strongly related to African admixture and these factors are the true modifiers of blood pressure.

A clinical and pharmacokinetic study of isolated limb perfusion with heat and melphalan for melanoma

The pharmacokinetics of isolated limb perfusion were studied to see what melphalan concentrations were achieved and how effective the isolation was. Twenty-eight patients received 32 limb perfusions with heat and melphalan for locally recurrent or level V melanoma. Melphalan was given 0.75 mg/kg for axillary/popliteal or 1.2 mg/kg for femoral perfusions with heat (perfusate 42 degrees C, limb 40 degrees C) for 1 hour. Melphalan concentratives were measured by high-performance liquid chromatography in seven patients. Peak perfusate melphalan concentrations were 6.1 to 115 mg/ml, which was one to two logs higher than peak systemic concentratives of melphalan. Isolation of the perfusate circuit from the systemic circulation was better for axillary and popliteal perfusions than for femoral perfusions (P less than 0.05). Complete responses were seen in 81% of evaluable patients; long-term local control was achieved in most patients, although many developed hematogenous metastases. Toxicity included erythema and edema in all, mild leukopenia in two, neuropathy in two, and amputation was required in one patient. Improvements in surgical technique include regional anesthesia to reduce vasospasms and transcutaneous measurement of fluorescein to measure leak. Perfusion with heat and melphalan remains the treatment of choice for in-transit metastases from melanoma.

A rapid screening technique for the detection of repeated DNA sequences in plant tissues

DNA sequences cloned from nuclear and mitochondrial chromosomes have been used as hybridisation probes to distinguish different plant genotypes. The probes are hybridised to squashed segments of tissue e.g. root tips. The 'squash-dot' method is rapid and suitable for screening large numbers of individual plants. One probe, specific for a rye repeated sequence family, enables rye chromosomes to be detected in wheat plants. A probe for ribosomal DNA enables plants with high or low numbers of ribosomal RNA genes to be distinguished. A maize mitochondrial DNA probe is used to distinguish plants with N, T or S cytoplasms.

Particle-enhanced turbidimetric inhibition immunoassay for theophylline evaluated with the Du Pont aca

We evaluated the Du Pont Particle-Enhanced Turbidimetric Inhibition Immunoassay (PETINIA) for theophylline. The imprecision (CV) of the assay was less than 4.7% between-run and less than 3.6% within-run for theophylline concentrations between 5 and 30 mg/L. Standard curves for the assay were linear for theophylline concentrations from 0 to 46 mg/L and were stable throughout the study (i.e., for at least three months). The monoclonal antibody against theophylline used in this assay increases specificity; of the possibly interfering drugs, metabolites, and anticoagulants tested, only 1,3-dimethyluric acid and EDTA showed measurable effects. Bilirubin (less than 300 mg/L), hemoglobin (less than 6 g/L), or lipemia (triglycerides less than 6 g/L) does affect the quality of the assay. Analytical recovery of theophylline added to serum (5 to 40 mg/L) averaged 98% (range 93% to 112%). Comparison of results for patients' sera by the PETINIA method with those by enzyme immunoassay (EMIT) and by "high-performance" liquid chromatography yielded slopes and intercepts not significantly different from 1.0 and 0.0, respectively, and correlation coefficients ranging from 0.986 to 0.995.

Particle-enhanced turbidimetric inhibition immunoassay for theophylline evaluated with the Du Pont aca

We evaluated the Du Pont Particle-Enhanced Turbidimetric Inhibition Immunoassay (PETINIA) for theophylline. The imprecision (CV) of the assay was less than 4.7% between-run and less than 3.6% within-run for theophylline concentrations between 5 and 30 mg/L. Standard curves for the assay were linear for theophylline concentrations from 0 to 46 mg/L and were stable throughout the study (i.e., for at least three months). The monoclonal antibody against theophylline used in this assay increases specificity; of the possibly interfering drugs, metabolites, and anticoagulants tested, only 1,3-dimethyluric acid and EDTA showed measurable effects. Bilirubin (less than 300 mg/L), hemoglobin (less than 6 g/L), or lipemia (triglycerides less than 6 g/L) does affect the quality of the assay. Analytical recovery of theophylline added to serum (5 to 40 mg/L) averaged 98% (range 93% to 112%). Comparison of results for patients' sera by the PETINIA method with those by enzyme immunoassay (EMIT) and by "high-performance" liquid chromatography yielded slopes and intercepts not significantly different from 1.0 and 0.0, respectively, and correlation coefficients ranging from 0.986 to 0.995.

Development and characterisation of a line of bread wheat, Triticum aestivum, which lacks the short-arm satellite of chromosome 1B and the Gli-B1 locus

About 360 offspring of a tri-parental cross were screened by gel electrophoresis and unexpectedly one of them did not contain chromosome 1B ω-gliadins derived from either of the primary parents. A line disomic for the ω-gliadin null was developed from the surviving embryo half of the unique grain. Two dimensional electrophoresis revealed that all the storage protein genes at Gli-B1, coding for γ-gliadins, β-gliadins and low-molecular-weight subunits of glutenin as well as the ω-gliadin, were not expressed. The nuclei of dividing root-tip cells were shown by light microscopy to lack the normal short-arm satellites of chromosome 1B, indicating that the genes for the missing storage proteins had been lost through a terminal deletion. Using a radioactive ribosomal RNA probe, the deficient 1B chromosomes were shown to contain ribosomal RNA genes demonstrating that at least two-thirds of the short arm was still present. Examination of serial sections of chromosome 1B at metaphase by low-power electron microscopy showed that the point of scission of this chromosome was within the secondary constriction where the ribosomal RNA genes are located. The Gli-B1 locus must therefore be carried on the short-arm satellite. Transmission of the deficient chromosome from female gametes to progeny was normal (i.e., about 50%) but from pollen it was poor (8.8%). Recombination mapping indicated that the distance from the ribosomal RNA genes (Nor1) to Glu-B1 was 22 cM, equivalent to 13 cM from Nor1 to the centromere.

C-banding at meiosis as a means of assessing chromosome affinities in the Triticeae

The meiotic chromosome pairing of one 'Chinese Spring' wheat aneuhaploid (3AL) and two 'Chinese Spring' aneuploid × rye hybrids (N3A-T3B and N5B-T5D × rye) were studied. These genotypes all display higher than normal levels of pairing which were analysed with the aid of the technique of C-banding. The results show that the pattern of pairing is neither random nor of an unrestricted homoeologous nature. Pairing is more frequent between unhanded (A and D genome) chromosomes, than between either unhanded (A or D genome) and banded (B or R genome) chromosomes, or between banded (B and R genome) chromosomes.

The identification of the nucleolus organiser chromosomes of diploid wheat

The two nucleolus organiser chromosomes of diploid wheat are identified as 1A and 5A by the combination of in situ hybridisation and cytological markers.

Interspecific variation in C-banded chromosomes of diploid Aegilops species

Based on an improved C-banding technique, the C-banding patterns of all 11 diploid Aegilops species were described and compared. All diploid species exhibit characteristically different patterns which enable the chromosomes of any complement to be identified individually. These patterns confirm existing genome symbols and provide further evidence for the suggested changes in genome symbols of Ae. umbellulata and Ae. sharonensis, U and S(sh) respectively. Furthermore, Ae. uniaristata should be given a separate symbol, probably N. Aegilops speltoides and Ae. sharonensis could be possible donors to the B genome of wheat. Interspecific divergence in these diploid species has been accompanied by either amplification or deletion as well as massive repatterning of heterochromatin from the centromere to the telomere.

The nucleolar organisers of tetraploid and hexaploid wheats revealed by in situ hybridisation

The technique of in situ hybridisation of cloned ribosomal DNA has been used to establish the numbers of nucleolar organising sites in a range of tetraploid and hexaploid wheats.

Investigation of a preferentially transmitted Aegilops sharonensis chromosome in wheat

An attempt to produce a set of addition lines of Aegilops sharonensis to the wheat variety 'Chinese Spring' produced only one addition line. This was due to preferential transmission of one chromosome from Ae. sharonensis. This chromosome was studied in detail by established cytological methods of chromosome observation and by the newer techniques of C-banding and in situ hybridization of a cloned DNA sequence. The chromosome was found to be partially homologous to an Ae. sharonensis chromosome of similar behaviour in another wheat addition line. The incomplete homology of the two Ae. sharonensis chromosomes was due to the presence of a translocated segment of a wheat chromosome. - Substitution lines of the Ae. sharonensis chromosome for wheat homoeologous group 4 were produced and the Ae. sharonensis chromosome thereby designated 4 S (l) .

Comparison of the chromosomes of Triticum timopheevi with related wheats using the techniques of C-banding and in situ hybridization

The chromosomes of the tetraploid wheats Triticum timopheevi (Genome AAGG) and T. araraticum (Genome AAGG) were C-banded at mitosis. The identity of the banded and unbanded chromosomes was then established by firstly making comparisons with the hexaploid species T. zhukovskyi which has the genome formula AAAAGG. Secondly, the meiotic pairing in F1 hybrids between T. timopheevi and diploid wheats was examined by means of C-banding. The results showed that the banded chromosomes belonged to the G genome, while the unbanded chromosomes belonged to the A genome. Only one of the two pairs of satellited chromosomes had strong heterochromatic bands. The relationship between the genomes of T. timopheevi and T. dicoccum (Genome AABB) was then assessed at meiosis in hybrids between these species, using the techniques of C-banding and in situ hybridisation of a cloned ribosomal RNA gene probe. It was concluded that there were differences both in the amount and distribution of heterochromatin and also translocation differences between the species.