Hepatic rupture caused by peliosis hepatis.

Peliosis hepatis is a rare entity that can affect children and cause fatal hepatic hemorrhage or hepatic failure. Radiographic findings are nonspecific and can resemble other hepatic pathologies such as cysts, abscesses, metastases, and hemangiomatosis. Peliosis hepatis can resolve spontaneously or by withdrawal of inciting medications. Certain cases may require surgical resection of the involved portions of the liver. Recently, fatal liver hemorrhage was reported in 2 pediatric patients with a rare congenital muscle disorder known as myotubular (centronuclear) myopathy. One of these patients was found at autopsy to have peliosis hepatis. The authors report the first successful treatment of life-threatening liver hemorrhage caused by peliosis hepatis in a child with myotubular myopathy. Awareness of this condition may reduce the catastrophic complications seen with peliosis hepatis.

Right atrial thrombus in a patient with stage IV carcinoma of the lung: is the surgical treatment the correct choice?

Thrombus in the right atrium or ventricle is rare and carries a mortality rate of 40%. Death frequently occurs when the thrombus moves toward the pulmonary arteries. Emergent treatment is therefore required. However there is no clear consensus regarding therapeutic management. We present here a patient with right atrial thrombus who underwent surgical exploration of the right atrium and successful thrombectomy.

The rise of divorce and separation in the United States, 1880-1990.

I use the Integrated Public Use Microdata Series to assess the potential effects of local labor-market conditions on long-term trends and race differences in marital instability. The rise of female labor-force participation and the increase in nonfarm employment are closely associated with the growth of divorce and separation. Moreover, higher female labor-force participation among black women and lower economic opportunities for black men may account for race differences in marital instability before 1940, and for most of such differences in subsequent years. However, unmeasured intervening cultural factors are probably responsible for at least part of these effects.

Defining genes that govern longevity in Caenorhabditis elegans.

We previously identified five regions on the chromosomal map of Caenorhabditis elegans, containing genes that help specify life span in this species, by comparing the genotypes of young and long-lived progeny from a cross between strains Bristol-N2 and Bergerac-BO [Ebert et al. (1993): Genetics 135:1003-1010]. Analyses of additional crosses, and of putative polymorphisms for the implicated genes, are necessary to clarify the roles of naturally occurring polymorphic alleles in determining longevity. We therefore carried out a second multigenerational cross, between strains Bristol-N2 and DH424 (both nonmutators at 20 degrees C), to create a different heterogeneous recombinant-inbred population. We again found strong evidence implicating multiple genes, which differ between the parental strains, in the determination of life span. Increased variance of survival, for F2 and homozygous F25 worms relative to F1 hybrids, is consistent with such alleles assorting randomly in the cross progeny. Moreover, chromosome mapping data corroborate the polygenic nature of this quantitative trait. Genotypes of young and very long-lived adult worms from a synchronous F15 population were determined by polymerase chain reaction, to identify the parental strain of origin for each of 10 polymorphic loci. Two regions, on chromosomes II and IV, each contain at least one gene with allelic differences in associated longevity. A recombinant-inbred Bergerac-BO x Bristol-N2 population, derived from the earlier cross between those strains, was exposed to an acute toxic level of hydrogen peroxide. Genotyping of H2O2-resistant worms implicated at least one of the five chromosomal regions previously identified in the same cross progeny as harboring a longevity-determining gene. Superoxide dismutase and catalase levels, determined for the three parental strains as they aged, confirm the existence of polymorphisms in the corresponding genes (or their regulatory mechanisms) inferred from the chromosome-II mapping data, and are consistent with the hypothesis that increased longevity is conferred by high levels of these enzymes late in life.

Longevity-determining genes in Caenorhabditis elegans: chromosomal mapping of multiple noninteractive loci.

We have used chromosome mapping with polymorphic markers to define genetic components governing life span in the nematode Caenorhabditis elegans. A complex recombinant-inbred population was derived from an interstrain cross, yielding > 1000 genotypes, each a composite of homozygous segments from the two parental strains. Genotypes were analyzed for the last-surviving 1-5% of worms in aging cohorts, and for young controls, by multiplex polymerase chain reaction using polymorphic markers to distinguish the parental alleles. We identified five regions of the genome at which one parental allele was significantly enriched in long-lived subpopulations. At four of five loci, the same alleles were selected in aging cohorts maintained under two different conditions, implying that these genes determine life span in differing environments.

The demography of the unrelated individual: 1900-1950.

This article is an analysis of the frequency and characteristics of unrelated individuals between 1900 and 1950. The much-heralded rise of the primary individual during the 20th century has been offset by a decline in the frequency of secondary individuals. The overall percentage of persons residing without family did not exceed turn-of-the-century levels until the 1970s. Using data from national microdata samples of the census for 1900, 1940, and 1950, the study applies decomposition techniques and life-course analysis to investigate these patterns. The results show that the decline of the secondary individual from 1900 to 1950 was largely a function of changing demographic composition, but the increase of primary individuals is linked to changing residential preferences.