Hospice care or assisted suicide: a false dichotomy

In this paper, the author argues that making assisted suicide available is not a contradictory position to espousing hospice care. He draws on historical and political examples to explain the ethical basis for this assertion. By defining the issue at stake as one of personal autonomy (the loss or gain thereof), the author challenges the argument that making assisted suicide available leads to a slippery slope towards euthanasia, eugenics, or genocide. He asserts that narrowing choices by preventing people from seeking assistance in suicide is more likely to lead us down the slippery slope towards coercive medical and state intervention in our lives.

The development of biological explanation: are children vitalists?

Whether and how an understanding of biological explantation changes with development was explored in interviews with 24-first graders, 24 third graders, and 24 adults. Participants were asked about the changeability of biological and psychological characteristics and the causal mechanisms underlying biological, psychological, and mechanical phenomena (using both open-ended and forced-choice questions). In saying how characteristics might be changed, children and adults similarly distinguished between biology and psychology; they also responded similarly to questions about specific processes underlying biological change. Children's attributions of intention or agency to biological organs or body parts (i.e., vitalistic attribution) did not differ from adults', contrary to previous findings. The authors concluded that children's thinking about biology is not necessarily more vitalistic than adults'.

Separation of polycyclic aromatic hydrocarbons by nonaqueous capillary electrophoresis using charge-transfer complexation with planar organic cations

In this study, we examine the use of charge-transfer interactions between polycyclic aromatic hydrocarbons (PAHs) and planar organic cations in nonaqueous capillary electrophoresis. Since the separations are performed in a purely nonaqueous medium, this method also facilitates the analysis of solutes that have low solubilities in aqueous or mixed media. Presented in this study are the separations of PAHs as well as the quantitative structure-migration relationships that assisted in achieving a better understanding of the forces through which the PAH molecules interact with the acceptor cation. It was found that, in addition to charge-transfer interactions, electrostatic and dispersive forces play an important role in PAH-cation binding.

Internal structure of phonetic categories: effects of speaking rate

Many studies have shown that listeners process speech in a rate-dependent manner, altering the location of phonetic category boundaries in accord with the acoustic consequences of a change in rate during speech production. In a recent series of papers that focused on a voicing contrast, we reported that the perceptual adjustment for rate is not limited to the region of the category boundary, but extends to well within the category, producing a change in which stimuli are perceived to be the best category exemplars. In the current paper, we provide evidence for the generality of this effect by showing analogous results for a /b/-/w/ contrast, specified by transition duration. The implications of these findings for models of rate-dependent processing are discussed.

The development of biological explanation: are children vitalists?

Whether and how an understanding of biological explantation changes with development was explored in interviews with 24-first graders, 24 third graders, and 24 adults. Participants were asked about the changeability of biological and psychological characteristics and the causal mechanisms underlying biological, psychological, and mechanical phenomena (using both open-ended and forced-choice questions). In saying how characteristics might be changed, children and adults similarly distinguished between biology and psychology; they also responded similarly to questions about specific processes underlying biological change. Children's attributions of intention or agency to biological organs or body parts (i.e., vitalistic attribution) did not differ from adults', contrary to previous findings. The authors concluded that children's thinking about biology is not necessarily more vitalistic than adults'.

Effect of charge on the interaction of site-specific photoimmunoconjugates with human ovarian cancer cells

A marked effect of charge modification on the uptake and phototoxicity of a photoimmunoconjugate (PIC) was demonstrated. A site-specific conjugation strategy was developed to attach the photosensitizer chlorin(e6) (c(e6)) to the F(ab')2 fragment of the murine antiovarian cancer monoclonal antibody OC125. Poly-L-lysine linkers carrying c(e6) with a cationic charge or by polysuccinylation with an anionic charge were used and covalently attached to partially reduced antibody via a heterobifunctional reagent. PICs were purified by column chromatography and were also radiolabeled with 125I. PIC binding and uptake were studied with a human ovarian cancer cell line, NIH-OVCAR-5, and a nonantigen-expressing colon cancer cell line, SW1116, and the data were compared with the binding and uptake of nonspecific rabbit IgG PICs. PICs with both cationic and anionic charges preserved antigen binding as shown by competition studies with native antibody, but the cationic PIC had up to 17 times higher cellular uptake of c(e6), probably due to enhanced internalization. The ratio of c(e6) to 125I retained by the cells varied with the likelihood of internalization and lysosomal degradation. The phototoxicity of the PICs generally varied with their uptake, but a correlation was found between lysosomal hydrolysis as measured by an increased cellular ratio of c(e6):125I and increased relative phototoxicity. These data suggest cationic PICs may have advantages for photoimmunotherapy of disseminated intracavity cancer following local administration.

Internal structure of voicing categories in early infancy

It is well established that young infants process speech in terms of perceptual categories that closely correspond to the phonetic categories of adult language users. Recently, Kuhl (1991) has provided evidence that this correspondence is not limited to the region of category boundaries: At least by 6-7 months of age, vowel categories of infants, like those of adults, have an internal perceptual structure. In the current experiments, which focused on a consonantal contrast, we found evidence of internally structured categories in even younger infants-3-4 months of age. The implications of these findings for the nature of the infant's earliest language-universal categories are discussed, as is the role of exposure to the native language in shaping these categories over the course of development.

Recombinant adeno-associated virus-mediated high-efficiency, transient expression of the murine cationic amino acid transporter (ecotropic retroviral receptor) permits stable transduction of human HeLa cells by ecotropic retroviral vectors

Adeno-associated virus has a broad host range, is nonpathogenic, and integrates into a preferred location on chromosome 19, features that have fostered development of recombinant adeno-associated viruses (rAAV) as gene transfer vectors for therapeutic applications. We have used an rAAV to transfer and express the murine cationic amino acid transporter which functions as the ecotropic retroviral receptor, thereby rendering human cells conditionally susceptible to infection by an ecotropic retroviral vector. The proportion of human HeLa cells expressing the receptor at 60 h varied as a function of the multiplicity of infection (MOI) with the rAAV. Cells expressing the ecotropic receptor were efficiently transduced with an ecotropic retroviral vector encoding a nucleus-localized form of beta-galactosidase. Cells coexpressing the ecotropic receptor and nucleus-localized beta-galactosidase were isolated by fluorescence-activated cell sorting, and cell lines were recovered by cloning at limiting dilution. After growth in culture, all clones contained the retroviral vector genome, but fewer than 10% (3 of 47) contained the rAAV genome and continued to express the ecotropic receptor. The ecotropic receptor coding sequences in the rAAV genome were under the control of a tetracycline-modulated promoter. In the presence of tetracycline, receptor expression was low and the proportion of cells transduced by the ecotropic retroviral vector was decreased. Modulation of receptor expression was achieved with both an episomal and an integrated form of the rAAV genome. These data establish that functional gene expression from an rAAV genome can occur transiently without genome integration.

Case report: failure of adrenal scintigraphy to exhibit 131I cholesterol uptake in a CT-demonstrated, surgically proven aldosteronoma

This is the case of a large 2 x 1.5 cm adrenal tumor demonstrated on CT scan that was proven biochemically and surgically to be an aldosteronoma and that did not concentrate 6-beta(131I)-iodo-methyl-19-norcholesterol (NP-59). Before the publication of this case, all CT-identified aldosteronomas of greater than 1 cm have concentrated NP-59. Previously, an adrenal mass of greater than 1 cm that failed to concentrate NP-59 was excluded from being an aldosteronoma. This concept must be reevaluated with the publication of this case.

Interstitial cystitis in children

PURPOSE

Interstitial cystitis has been rarely reported in children. We present our experience with 16 children in whom clinical symptomatology and cystoscopic findings were consistent with the diagnosis of interstitial cystitis.

MATERIALS AND METHODS

We retrospectively reviewed the charts of 20 children referred for chronic sensory urgency, frequency and bladder pain who underwent cystoscopy and hydrodistension. Four patients were excluded from study because of infection identified at cystoscopy or lack of cystoscopic changes with hydro-distension.

RESULTS

Patient age at onset of first symptoms ranged from 2 to 11 years (median 4.5) and age at diagnosis ranged from 3 to 16 years (mean 8.2). Of the 16 children 14 (88%) presented with symptoms of urinary frequency and sensory urgency, and in 13 (81%) lower abdominal pain was relieved by voiding. None of the children had motor urgency. Urodynamic evaluation in 8 cases revealed early bladder sensation with no evidence of involuntary bladder contractions. Diffuse glomerulations and terminal hematuria were demonstrated in all patients after hydro-distension. Followup was available for 14 patients. Relief of symptoms occurred after hydro-distension in all children except 1. Seven children (50%) required repeat hydro-distension.

CONCLUSIONS

Children with symptoms of bladder pain, urinary frequency and sensory urgency have bladder changes on cystoscopy consistent with interstitial cystitis. Although rare, this condition is recognizable and it should not be confused with dysfunctional voiding in which complaints are secondary to involuntary bladder contractions.

Intercellular transfer of a glycosylphosphatidylinositol (GPI)-linked protein: release and uptake of CD4-GPI from recombinant adeno-associated virus-transduced HeLa cells

A diverse group of GPI-anchored protein structures are ubiquitously expressed on the external cell membranes of eukaryotes. Whereas the physiological role for these structures is usually defined by their protein component, the precise biological significance of the glycolipid anchors remains vague. In the course of producing a HeLa cell line (JM88) that contained a recombinant adeno-associated virus genome expressing a GPI-anchored CD4-GPI fusion protein on the surface of the cells, we noted the transfer of CD4-GPI to native HeLa cells. Transfer occurred after direct cell contact or exposure to JM88 cell supernatants. The magnitude of contact-mediated CD4-GPI transfer correlated with temperature. Supernatant CD4-GPI also attached to human red blood cells and could be cleaved with phosphatidylinositol-specific phospholipase C. The attached CD4-GPI remained biologically active after transfer and permitted the formation of syncytium when coated HeLa cells were incubated with glycoprotein 160 expressing H9 cells. JM88 cells provide a model for the production, release, and reattachment of CD4-GPI and may furnish insight into a physiologic role of naturally occurring GPI-anchored proteins. This approach may also allow the production of other recombinant GPI-anchored proteins for laboratory and clinical investigation.

Activity and molecular weight of protein tyrosine phosphatases in cell lysates determined by renaturation after gel electrophoresis

A procedure for renaturing and detecting the activity of protein tyrosine phosphatases (PTPases) after sodium dodecyl sulfate (SDS)-gel electrophoresis with greatly improved sensitivity and resolution is described. Epidermal growth factor receptor-kinase, c-src kinase, and focal adhesion kinase were phosphorylated on tyrosine with 32PO4 and incorporated into gels prior to electrophoresis. These proteins are dephosphorylated when cellular proteins are electrophoresed and the separated PTPases are renatured in the gel by removing SDS with extensive washing. With whole cell lysates, at least eight separate bands of decreased radioactivity corresponding to PTPase activity with molecular weights between 110 and 34 kDa are seen in autoradiographs of the dried gels. PTPases detected are similar with different cell types and with the three 32P-labeled protein substrates, although they are different in cytosolic and membrane-associated fractions. A PTPase detected above 200 kDa in wheat germ agglutinin eluates from solubilized cells suggests that some receptor PTPases can be renatured. While microgram levels of recombinant PTP-1C are required for detection, nanogram levels of recombinant PTP-1B are easily detected. Assaying the activity of renatured PTPases after they have been separated by molecular weight in SDS gel electrophoresis provides a simple and rapid means of determining the activity of individual PTPases in cell fractions.

Treatment with the Reliance urinary control insert: one-year experience

The 1-year experience of 63 women using an intraurethral insert for the management of stress or mild mixed urinary incontinence is presented, emphasizing safety and efficacy. Objective criteria, including standardized pad weight tests and patient diaries, were employed to evaluate the device's effectiveness. At study outset, 82% of the patients were completely dry with the device in situ, with an additional 16% of patients significantly improved. At 12 months, 79% of the patients were completely dry, and 16% were significantly improved. This result is consistent with the significant improvement (P < 0.0001) in the number of urinary incontinence episodes reported in patient diaries. Women reported that the device significantly improved their ability to stay dry over a number of routine and physically demanding daily activities. The device was increasingly easy to use and more comfortable over time (P < 0.0001). The latter finding was confirmed by a decline in patient reports of "sensation of device presence" over the duration of the study (35% at 1 week v 7% at 12 months). Untoward events included gross hematuria (24%), device-related bladder mucosal irritation (9%), and symptomatic bacteriuria (30%). Such side effects were expected for this type of device, were easily managed without significant medical intervention, and did not result in any long-term clinical sequelae. The great reduction in the number of episodes of urinary incontinence, the low rate of significant problems associated with device use, and ease of use make the intraurethral insert a useful management alternative for women with stress urinary incontinence.

Epidurals redefined in analgesia and anesthesia: a distinction with a difference

Advances in our understanding of pain have created a new and meaningful distinction between epidural analgesia and anesthesia. The principles underlying this important difference are reviewed from a childbirth perspective and promote a reconsideration of the role of pain relief in labor versus the need for anesthesia at delivery. An epidural analgesic technique is presented with fresh implications for several old intrapartum practices. The analgesia/ anesthesia distinction in epidural therapy offers new opportunities and flexibility for safety and fulfillment in childbirth.

Mimotope/anti-mimotope probing of structural relationships in platelet glycoprotein Ib alpha

A bacteriophage library displaying random decapeptides was used to characterize the binding preference of C-34, a monoclonal antibody originally raised against platelet-type von Willebrand disease platelets heterozygous for the mutation 23OWKQ (G --> V)233V234 in the alpha chain of glycoprotein Ib (GPIb alpha). Three rounds of biopanning C-34 against the library resulted in striking convergence upon the sequence WNWRYREYV. Since no portion of this sequence corresponds to a recognizable peptide sequence within human platelet GPIb alpha, it may be considered a "mimotope" of the naturally occurring C-34 epitope, presumably bearing similarity to it in three-dimensional structure. Synthetic AWNWRYREYV peptide preincubated with C-34 fully neutralized the ability of C-34 to inhibit platelet aggregation, with an IC50 of approximately 6 microg/ml. When biotinylated AWNWRYREYV was subsequently bioparmed against the original decapeptide library, the sole clone demonstrating inhibitory activity above background level in a functional platelet assay displayed the sequence RHVAWWRQGV, and chemically synthesized peptide fully inhibited ristocetin-induced aggregation, with an IC50 of 200-400 microg/ml. Synthesized RHVAWWKQGV peptide exerted only slight inhibition, whereas RHVAWWKQVV peptide showed potent inhibitory activity. Moreover, whereas synthesized wild-type 228YVWKQGVDVK237 GPIb alpha peptide was virtually without inhibitory activity, the 228YVWKQ(G -->V) 233VDVK237 peptide fully inhibited ristocetin-induced aggregation, with an IC50 of approximately 400 microg/ml. These studies raise the possibility of an intramolecular association of peptide regions within GPIb alpha that may play a role in the regulation of von Willebrand factor-dependent platelet aggregation.

The influence of bolus volume and viscosity on anterior lingual force during the oral stage of swallowing

The influence of bolus volume and viscosity on the distribution of anterior lingual force during the oral stage of swallowing was investigated using a new force transducer technology. The maximum force amplitudes from 5 normal adults were measured simultaneously at the mid-anterior, right, and left lateral tongue margins during 10 volitional swallows of 5-, 10-, and 20-ml volumes of water, applesauce, and pudding. Results indicated significant increases in peak force amplitude as viscosity increased. Volume did not significantly influence maximum lingual force amplitudes. Individual subjects demonstrated consistent patterns of asymmetrical force distribution across the lingual margins tested. The results suggest that bolus-specific properties influence the mechanics of oral stage lingual swallowing. This finding has important clinical implications in the assessment and treatment of dysphagic individuals.

Oral hypoglycemic agents in type II diabetes mellitus

The patient with type II, or non-insulin-dependent, diabetes mellitus (NIDDM) is characterized by obesity and insulin resistance, with resultant hyperinsulinemia and hyperglycemia. Sulfonylureas are the chief therapy for patients with NIDDM; for a limited time, these agents stimulate increased insulin secretion. With chronic administration, sulfonylureas improve the diabetic patient's insulin activity by increasing cellular insulin receptors and reducing insulin postreceptor defects. Metformin, a drug in the biguanide class, is now approved for use in the United States. This drug does not stimulate insulin release but works by lowering glucose in peripheral tissues. It can be used alone or in combination with a sulfonylurea. With sulfonylureas and metformin, therapy for the patient with NIDDM can be more effectively tailored.

Remission of severe epidermolysis bullosa acquisita induced by extracorporeal photochemotherapy

We report a patient with severe epidermolysis bullosa acquisita (EBA) whose disease was refractory to conventional treatments. New bullae continued to develop over greater than 50% of his body surface area despite therapy. His course was complicated by hyperglycaemia, sepsis, hypoxia caused by pulmonary Aspergillus infection and an idiopathic cardiomyopathy. His EBA resolved after treatment with extracorporeal photochemotherapy (ECP). Hence, ECP may be effective in the treatment of severe EBA which has failed to respond to standard treatment regimens.