Say no to inadequate tort reform

From his vantage point as president of a large multispecialty group practice. Dr Montgomery has observed the direct effects that medical malpractice liability has had on healthcare costs. Here he offers a counterpoint to the Clinton plan's malpractice provisions and enumerates his own recommendations for meaningful tort reform.     

Polymerase chain reaction amplification analyses of clonality in T-cell malignancy including peripheral T-cell lymphoma

Clonality in T-cell malignancy was investigated using T-cell receptor (TcR) V beta 1-20 family primers and polymerase chain reaction amplification (PCR) of cDNA prepared from tissue biopsies and blood involved with tumour. Secondary PCR amplification of the VDJ joints of primary PCR products was performed to distinguish clonal from polyclonal products, and clonal V beta gene products were confirmed by direct PCR sequencing in the majority of cases. In eight T-cell malignancies including T-cell acute lymphoblastic leukaemia (T-ALL) and T-cell chronic lymphocytic leukaemia (T-CLL) shown to be clonal by Southern blot analysis, one or two primary PCR products were identified and shown to be clonal. In five cases of peripheral T-cell lymphoma (PTCL) all V beta 1-20 families were identified after primary PCR amplification, and clonal products were identified in two cases after secondary amplification; TcR V beta clonal families could not be demonstrated in the remaining three cases. These data were in agreement with previous Southern blot analysis of these cases, and confirmed the presence of reactive T cells in PTCL as well as providing further evidence for the genotypic heterogeneity of this entity. In the remaining case, a blood lymphocytosis, primary PCR amplification produced predominant TcR V beta 6 and V beta 12 family products, of which the V beta 6 family proved clonal after secondary PCR amplification. There was no evidence for overrepresentation of TCR V beta families by the tumour populations in this study, furthermore the data confirm the involvement of reactive cells in T-cell malignancy and the genetic heterogeneity of PTCL.     

Multicarrier modulation for narrowband PCS

Investigation of multicarrier modulation has demonstrated the feasibility of using this modulation format to deliver relatively high channel bit rates (24 kbps) to a low cost, pager-like personal communications service (PCS) terminal that enjoys long battery life (e.g., one month on a few pen-light cells). This is to be compared to the 1200 bps carried by typical current paging systems or the 6250 bps attained by the new ERMES paging system. While more complex modulation formats, such as PSK and QAM, might achieve higher bit rates in less (power, size, cost) constrained environments, amplitude keying of the component subcarriers allows simple noncoherent energy detection that is found to be robust in this short message delivery application     

Accommodation of a D-Phe residue into a right-handed 3(10)-helix: structure of Boc-D-Phe-(Aib)4-Gly-L-Leu-(Aib)2-OMe, an analogue of the amino terminal segment of antiamoebins and emerimicins

Recently an unstable trinucleotide CTG repeat, located within the 3' untranslated region of a gene on 19q13.3 was discovered in kindreds with myotonic dystrophy (DM). The age-of-onset/severity of DM shows a good correlation with CTG repeat size, and pedigrees and data reported to date have shown a striking trend toward amplification of the size of the CTG repeat during transmission from parent to child. The amplification has been accepted as the biological explanation for anticipation in the clinical severity observed in many families with DM. In this paper we report on 3 families where CTG amplification decreased during transmission from parent to child. In one case there was a gene conversion event, while in the remaining 2 there was a simpler reduction in the size of the repeat length. The changes appear to have been accompanied by a reduction in clinical severity in the child when compared to the parent. These observations are discussed in terms of their clinical implications and the biases that may exist in much of the reported data.     

Localization of allatostatin-immunoreactive material in the central nervous system, stomatogastric nervous system, and gut of the cockroach Blattella germanica

Immunoreactivity against peptides of the allatostatin family having a typical YXFGL-NH2 C-terminus has been localized in different areas of the central nervous system, stomatogastric nervous system and gut of the cockroach Blattella germanica. In the protocerebrum, the most characteristic immunoreactive perikarya are situated in the lateral and median neurosecretory cell groups. Immunoreactive median neurosecretory cells send their axons around the circumesophageal connectives to form arborizations in the anterior neuropil of the tritocerebrum. A group of cells in the lateral aspect of the tritocerebrum project to the antennal lobes in the deutocerebrum, where immunoreactive arborizations can be seen in the periphery of individual glomeruli. Nerve terminals were shown in the corpora allata. These terminals come from perikarya situated in the lateral neurosecretory cells in the pars lateralis and in the subesophageal ganglion. Immunoreactive axons from median neurosecretory cells and from cells positioned in the anteriormost part of the tritocerebrum enter together in the stomatogastric nervous system and innervate foregut and midgut, especially the crop and the valve between the crop and the midgut. The hindgut is innervated by neurons whose perikarya are located in the last abdominal ganglion. Besides immunoreactivity in neurons, allatostatin-immunoreactive material is present in endocrine cells distributed within the whole midgut epithelium. Possible functions for these peptides according to their localization are discussed.     

Identification of potent P2Y-purinoceptor agonists that are derivatives of adenosine 5'-monophosphate

1. A series of chain-extended 2-thioether derivatives of adenosine monophosphate were synthesized and tested as agonists for activation of the phospholipase C-linked P2Y-purinoceptor of turkey erythrocyte membranes, the adenylyl cyclase-linked P2Y-purinoceptor of C6 rat glioma cells, and the cloned human P2U-receptor stably expressed in 1321N1 human astrocytoma cells. 2. Although adenosine monophosphate itself was not an agonist in the two P2Y-purinoceptor test systems, eleven different 2-thioether-substituted adenosine monophosphate analogues were full agonists. The most potent of these agonists, 2-hexylthio AMP, exhibited an EC50 value of 0.2 nM for activation of the C6 cell receptor. This potency was 16,000 fold greater than that of ATP and was only 10 fold less than the potency of 2-hexylthio ATP in the same system. 2-hexylthio adenosine was inactive. 3. Monophosphate analogues that were the most potent activators of the C6 cell P2Y-purinoceptor were also the most potent activators of the turkey erythrocyte P2Y-purinoceptor. However, agonists were in general more potent at the C6 cell receptor, and potency differences varied between 10 fold and 300 fold between the two receptors. 4. Although 2-thioether derivatives of adenosine monophosphate were potent P2Y-purinoceptor agonists no effect of these analogues on the human P2U-purinoceptor were observed. 5. These results support the view that a single monophosphate is sufficient and necessary for full agonist activity at P2Y-purinoceptors, and provide insight for strategies for development of novel P2Y-purinoceptor agonists of high potency and selectivity.     

A PET study of the neural systems of stuttering

The cause of stuttering is unknown. Failure to develop left-hemispheric dominance for speech is a long-standing theory although others implicated the motor system more broadly, often postulating hyperactivity of the right (language nondominant) cerebral hemisphere. As knowledge of motor circuitry has advanced, theories of stuttering have become more anatomically specific, postulating hyperactivity of premotor cortex, either directly or through connectivity with the thalamus and basal ganglia. Alternative theories target the auditory and speech production systems. By contrasting stuttering with fluent speech using positron emission tomography combined with chorus reading to induce fluency, we found support for each of these hypotheses. Stuttering induced widespread overactivations of the motor system in both cerebrum and cerebellum, with right cerebral dominance. Stuttered reading lacked left-lateralized activations of the auditory system, which are thought to support the self-monitoring of speech, and selectively deactivated a frontal-temporal system implicated in speech production. Induced fluency decreased or eliminated the overactivity in most motor areas, and largely reversed the auditory-system underactivations and the deactivation of the speech production system. Thus stuttering is a disorder affecting the multiple neural systems used for speaking.     

Do We Stand on Common Ground? A Threat Appraisal Model for Terror Alerts Issued by the Department of Homeland Security

The fabric and faces of threat, and the expediency and efficiency in the communication of threat, are examined with a threat appraisal model. This model is empirically tested on an ongoing communication challenge, the issuance of terror alerts by the United States' Department of Homeland Security (DHS), focusing on how threat is appraised by both the conservative and liberal audiences. Findings showed a shared view by the DHS and conservative audiences on the levels and nature of threats; liberal audiences thought otherwise. Though there appeared to be a consensus between the conservative and liberal audiences on the efficacy of threat communication, more internal consistency within DHS is needed to optimise its effectiveness.