Simple electromyographic biofeedback treatment for chronic pediatric constipation/encopresis: Preliminary report

Pediatric constipation/encopresis is thought to be due, in part, to paradoxical constriction of the external anal sphincter (EAS) muscle during attempted defecation. This inappropriate contraction can lead to delayed, impacted, painful, and infrequent bowel movements. Standard Medical Care (SMC) involves disimpaction with enemas, followed by laxative therapy and diet modification, to maintain frequent soft stools. Using the case control method, the efficacy of SMC alone was compared with SMC plus EAS electromyographic biofeedback aimed at eliminating paradoxical contraction. Thirteen consecutive chronically constipated children received SMC plus biofeedback, and were compared with 13 age- and sex-matched children who received only SMC. Biofeedback subjects demonstrated post-treatment elimination of EAS paradoxical constriction. At 16 months follow-up parents of biofeedback children reported significantly greater improvement in constipation, encopresis, laxative use, and painful bowel movements compared to SMC.This research report was supported by the NIH under grant No. RO1 HD 28160.     

Aristotle's biology and the transplantation of organs

Conclusion It would be redundant to repeat the general thesis and specific claims advanced in the introduction. Yet in concluding I should like to draw attention to several broader themes that run through the article. One is that understanding Aristotle's biology demands attention to his psychology and metaphysics as well as to what some readers may regard as his strictly biological writings.Another is that Aristotle's views on homonymy and potentiality     

Seed development in Pisum

The Ih and lh _i alleles have been shown previously to reduce the level of endogenous gibberellin A₁ (GA₁) in shoots of pea (Pisum sativum L.), resulting in a dwarf phenotype compared with the wild type, cv. Torsdag (Lh). In addition, plants homozygous for the lh ⁱ allele have reduced seed yield compared with Lh (tall, wild type) and lh (dwarf) plants. In this paper we show that the lh ⁱ mutation is expressed in developing seeds and pods. Comparison of GA levels in young shoots and developing seeds of genotypes lh and lh ⁱ demonstrates that the relative severity of the two mutations varies in different tissues. Homozygous h ⁱ seeds have reduced GA levels, weigh less, and are less likely to develop to maturity when compared with Lh seeds. However, fertilization of lh ⁱ plants with Lh pollen increases seed GA levels, seed weight and seed survival, indicating that an increase in seed GA levels due to the presence of the Lh allele can restore normal seed growth. Pods developing on self-pollinated lh ⁱ plants are shorter than pods on Lh (wild type) plants, although this may be an indirect effect of the increased seed abortion of lh _i plants. Based on these results we suggest that endogenous GAs play an important role in the development of seeds of P. sativum L.Abbreviations GA_(n) gibberellin A_n We wish to thank Katherine McPherson, Peter Newman, Leigh Johnson and Peter Bobbi for technical assistance, Professor L. Mander (ANU, Canberra) and Professor B.O. Phinney (UCLA, USA) for labelled GA standards, and the Australian Research Council for financial support.     

Ultrastructure of human dermal mast cells in 29 different lysosomal storage diseases

The effect of lysosomal storage diseases on the ultrastructure of human mast cells has not previously been reported. Indeed, there has been little published evidence indicating that mast cells contain typical lysosomes. However, mast cell cytoplasmic granules contain hydrolases similar to those found in lysosomes, but which differ from lysosomal hydrolases in exhibiting optimal activity at higher pH. We therefore examined by transmission electron microscopy the dermal mast cells in 58 biopsies of patients exhibiting 1 of 29 different lysosomal storage diseases. We found mast cells containing abnormal lysosomes in 16 of these disorders. In 6 of these 16 diseases, the mast cells' cytoplasmic granules appeared normal. These observations indicate that human mast cells can contain lysosomes, and provide evidence that the enzymes affected by lysosomal storage diseases are active in mast cells.     

Body condition of a small passerine bird: ultrasonic assessment and significance in overwinter survival

The fitness benefits of intraspecific variation in physiological attributes have rarely been measured. Body condition, defined as the current status of metabolic reserves relative to likely demands, has often been implicated in subsequent survival, but has proved difficult to assess reliably in the live animal. A technique for assessing body condition, in terms of the main protein reserve of small birds, is presented. Pectoralis muscle thickness was measured in live birds using ultrasound reflection from the sternum. The relationship between the relative size of pectoralis muscles in autumn and the likelihood of overwinter survival in the dipper Cinclus cinclus was examined. The pectoralis reserves of male dippers surviving overwinter were significantly greater than those of birds which died or disappeared between late November and the breeding season in April. In contrast, variation in autumn condition of females was unrelated to overwinter survival.     

Surveying nonvisual arrestins reveals allosteric interactions between functional sites

Arrestins are important scaffolding proteins that are expressed in all vertebrate animals. They regulate cell-signaling events upon binding to active G-protein coupled receptors (GPCR) and trigger endocytosis of active GPCRs. While many of the functional sites on arrestins have been characterized, the question of how these sites interact is unanswered. We used anisotropic network modeling (ANM) together with our covariance compliment techniques to survey all the available structures of the nonvisual arrestins to map how structural changes and protein-binding affect their structural dynamics. We found that activation and clathrin binding have a marked effect on arrestin dynamics, and that these dynamics changes are localized to a small number of distant functional sites. These sites include α-helix 1, the lariat loop, nuclear localization domain, and the C-domain β-sheets on the C-loop side. Our techniques suggest that clathrin binding and/or GPCR activation of arrestin perturb the dynamics of these sites independent of structural changes.     

Scale and the Explanation of Demographic Change: 3,500 Years in the Valley of Oaxaca

Explicit attention to scale provides ways to relate the long run of archaeology to the shorter moments of ethnography and history, and ways to link biology and ecology to political economy. In the Valley of Oaxaca, in southern Mexico, the long–term history of the aggregate, regional population was constrained by relatively stable factors of human biology and ecology. However, significant, patterned variation in shorter–term, disaggregated, local demographic change was caused by shifts in political economy, both in the past and in recent times. Such conclusions are made possible by an unusual datasetthat combines recent, historical, and archaeological population estimates for a whole region covering a 3,500–year period, from initial settled villages to the present, for every place ever inhabited. [Keywords: population, demography, political economy, Oaxaca, Mexico]     

Histories and Stories from Chiapas: Border Identities in Southern Mexico.

Histories and Stories from Chiapas: Border Identities in Southern Mexico. R. Aída Hernández Castillo. Texas: University of Texas Press, 2001. 317 pp.     

The mechanism of resistance to paraquat is strongly temperature dependent in resistant Hordeum leporinum Link and H. glaucum Steud.

Paraquat-resistant biotypes of the closely-related weed species Hordeum leporinum Link and H. glaucum Steud. are highly resistant to paraquat when grown during the normal winter growing season. However, when grown and treated with paraquat in summer, these biotypes are markedly less resistant to paraquat. This reduced resistance to paraquat in summer is primarily a result of increased temperature following herbicide treatment. The mechanism governing this decrease in resistance at high temperature was examined in H. leporinum. No differences were observed between susceptible and resistant biotypes in the interaction of paraquat with isolated thylakoids when assayed at 15, 25, or 35 °C. About 98 and 65% of applied paraquat was absorbed through the leaf cuticle of both biotypes at 15 and 30 °C, respectively. Following application to leaves, more herbicide was translocated in a basipetal direction in the susceptible biotype compared to the resistant biotype at 15 °C. However, at 30 °C more paraquat was translocated in a basipetal direction in the resistant biotype. Photosynthetic activity of young leaf tissue from within the leaf sheath which had not been directly exposed to paraquat was measured 24 h after treatment of plants with para. quat. This activity was inhibited in the susceptible biotype when plants were maintained at either 15 °C or 30 °C after treatment. In contrast, photosynthetic activity of such tissue of the resistant biotype was not inhibited when plants were maintained at 15 °C after treatment, but was inhibited at 30 °C. The mechanism of resistance in this biotype of H. leporinum correlates with decreased translocation of paraquat and decreased penetration to the active site. This mechanism is temperature sensitive and breaks down at higher temperatures.We are grateful to Zeneca Agrochemicals, Jealotts Hill, Berkshire, UK who provided [¹⁴C]paraquat. E.P. was supported through a Ph.D. scholarship from the Australian International Development Assistance Bureau and C.P. was the recipient of an Australian Research Council Postdoctoral Fellowship.     

Primate terminal complement inhibitor homologues of human CD59

The nucleotide sequence data reported in this paper have been submitted to the GenBank nucleotide sequence database and have been assigned the accession numbers L22862 (African green monkey CD59) and L22863 (baboon CD59)