Molecular Profiling and Treatment Pattern Differences between Intrahepatic and Extrahepatic Cholangiocarcinoma

BACKGROUND

Treatment patterns for intrahepatic cholangiocarcinoma (ICC) and extrahepatic cholangiocarcinoma (ECC) differ, but limited studies exist comparing them. This study examines differences in molecular profiling rates and treatment patterns in these populations, focusing on use of adjuvant, liver-directed, targeted, and investigational therapies.

METHODS

This multi-center collaboration included patients with ICC or ECC treated at one of eight participating institutions. Retrospective data were collected on risk factors, pathology, treatments, and survival. Comparative statistical tests were two-sided.

RESULTS

Among 1,039 patients screened, 847 patients met eligibility (ICC = 611, ECC = 236). Patients with ECC were more likely than those with ICC to present with early-stage disease (53.8% vs 28.0%), undergo surgical resection (55.1% vs 29.8%), and receive adjuvant chemoradiation (36.5% vs 4.2%), (all p < 0.00001). However, they were less likely to undergo molecular profiling (50.3% vs 64.3%) or receive liver directed therapy (17.9% vs 35.7%), targeted therapy (4.7% vs 18.9%), and clinical trial therapy (10.6% vs 24.8%), (all p < 0.001). In patients with recurrent ECC after surgery, the molecular profiling rate was 64.5%. Patients with advanced ECC had a shorter median overall survival than those with advanced ICC (11.8 vs 15.1 months, p < 0.001).

CONCLUSIONS

Patients with advanced ECC have low rates of molecular profiling, possibly in part due to insufficient tissue. They also have low rates of targeted therapy use and clinical trial enrollment. While these rates are higher in advanced ICC, the prognosis for both subtypes of cholangiocarcinoma remains poor, and a pressing need exists for new effective targeted therapies and broader access to clinical trials.

Moving From Transactional to Relational: How Funders Can Work in Partnership With Black, Indigenous and People of Color Communities

BACKGROUND

The Racial Equity Coalition (REC) formed to address persistent educational disparities. The coalition was composed of 14 Black, Indigenous and People of Color (BIPOC) organizations that provide culturally integrative youth services.

OBJECTIVES

REC, with support from United Way of King County, engaged in participatory research to identify commonalities and shared struggles to inform collective action. Participatory research aligns with REC's commitment to equitable participatory processes. This article focuses on REC's experiences with funders. The objective was to understand what creates positive and challenging experiences with funders, and to identify recommendations for funders to become more culturally responsive.

METHODS

A research committee was formed including representatives of nine REC organizations and United Way of King County staff. The committee conducted interviews with each of the 14 REC organizations and conducted thematic analysis of interview transcripts. Through participatory analysis, the committee drafted narratives that were further refined through a series of research retreats attended by all REC organizations.

RESULTS

Recommendations were to incentivize collaboration, listen to communities to create culturally responsive definitions of success and measurement strategies, arrive at mutually agreed upon approaches with organizations, honor the connections BIPOC organizations have with their communities, and provide unrestricted funding to allow BIPOC organizations greater agency.

CONCLUSIONS

A major challenge for BIPOC organizations is navigating White dominant culture that too often shows up in funding requirements. Having to fit dominant culture standards stifles BIPOC organizations' abilities to meet community needs and the responsiveness of their approaches. REC identified recommendations for funders to be more culturally responsive and community centered.

Geostatistical Mapping of Salinity Conditioned on Borehole Logs, Montebello Oil Field, California

We present a geostatistics-based stochastic salinity estimation framework for the Montebello Oil Field that capitalizes on available total dissolved solids (TDS) data from groundwater samples as well as electrical resistivity (ER) data from borehole logging. Data from TDS samples (n = 4924) was coded into an indicator framework based on falling below four selected thresholds (500, 1000, 3000, and 10,000 mg/L). Collocated TDS-ER data from the surrounding groundwater basin were then employed to produce a kernel density estimator to establish conditional probabilities for ER data (n = 8 boreholes) falling below the selected TDS thresholds within the Montebello Oil Field area. Directional variograms were estimated from these indicator coded data, and 500 TDS realizations from conditional indicator simulation were generated for the subsurface region above the Montebello Oil Field reservoir. Simulations were summarized as 3D maps of median TDS, most likely salinity class, and probability for exceeding each of the specified TDS thresholds. Results suggested TDS was below 500 mg/L in most of the study area, with a trend toward higher values (500 to 1000 mg/L) to the southwest; consistent with the average regional groundwater flow direction. Discrete localized zones of TDS greater than 1000 mg/L were observed, with one of these zones in the greater than 10,000 mg/L range; however, these areas were not prevalent. The probabilistic approach used here is adaptable and is readily modified to include additional data and types and can be employed in time-lapse salinity modeling through Bayesian updating.

Minimum energy requirements for desalination of brackish groundwater in the United States with comparison to international datasets

This paper uses chemical and physical data from a large 2017 U.S. Geological Survey groundwater dataset with wells in the U.S. and three smaller international groundwater datasets with wells primarily in Australia and Spain to carry out a comprehensive investigation of brackish groundwater composition in relation to minimum desalination energy costs. First, we compute the site-specific least work required for groundwater desalination. Least work of separation represents a baseline for specific energy consumption of desalination systems. We develop simplified equations based on the U.S. data for least work as a function of water recovery ratio and a proxy variable for composition, either total dissolved solids, specific conductance, molality or ionic strength. We show that the U.S. correlations for total dissolved solids and molality may be applied to the international datasets. We find that total molality can be used to calculate the least work of dilute solutions with very high accuracy. Then, we examine the effects of groundwater solute composition on minimum energy requirements, showing that separation requirements increase from calcium to sodium for cations and from sulfate to bicarbonate to chloride for anions, for any given TDS concentration. We study the geographic distribution of least work, total dissolved solids, and major ions concentration across the U.S. We determine areas with both low least work and high water stress in order to highlight regions holding potential for desalination to decrease the disparity between high water demand and low water supply. Finally, we discuss the implications of the USGS results on water resource planning, by comparing least work to the specific energy consumption of brackish water reverse osmosis plants and showing the scaling propensity of major electrolytes and silica in the U.S. groundwater samples.

Beliefs about cybersex and Internet-mediated sex of Latino men who have Internet sex with men: relationships with sexual practices in cybersex and in real life

Cybersex (engaging in sexual self-stimulation while online with another person) and meeting partners for sex are commonly reported among men who have Internet sex with men (MISM). We studied 1,026 Latino MISM in the US and constructed a scale to measure beliefs about cybersex. Respondents were recruited to an online Internet study and compensated for their effort. Factor analysis indicated that there were three dimensions: (1) liking cybersex: perceived anonymity and safety of cybersex; (2) potential for greater IRL interaction in seeking partners on the Internet; and (3) a dimension of negative beliefs about Internet contacts which was not psychometrically stable. Safety referred to physical and HIV-related safety. We formed two scales to describe the first two dimensions. Respondents who were high on the 'liking cybersex: perceived anonymity and safety' scale were more likely than low scorers to use chat-rooms and webcams. They were also more likely than low scorers to have had cybersex and phone sex before meeting. Those who were high on the 'IRL interaction' scale were more likely than low scorers to use e-mail, bulletin boards and paid websites. However, there was significantly less disclosure about HIV status and discussion about safer sex by those higher on the 'IRL interaction scale', and when sex in real life did occur, those higher on the 'IRL interaction' scale were more likely to have receptive oral or anal sex, whereas those high on the 'liking cybersex: perceived anonymity/safety' scale were less likely to have insertive sex or be drunk/high. MISM scoring high on the 'IRL interaction' scale were significantly more likely than low scorers to prefer to meet partners on the Internet. We discuss the implications of the Internet for MSM and for sexual IRL interactions in the Internet age.

Surgical treatment of chondrosarcoma of the sternum

Purpose: We reviewed all tumours of the sternum referred to The London Bone and Soft Tissue Tumour Service between 1956 and 1997 inclusive.

Patients and results: There were eight patients with this pathology, the male to female ratio was 3:1 and their mean age was 53 years. Of these patients, three are alive and disease free, one is alive with recurrence, and four have died, two of the consequences of the disease and two of unrelated causes. Surgery is the principal treatment of these tumours both for excision and subsequent reconstruction.

Discussion: Extended disease-free survival is possible with correct diagnosis, complete excision at the first operation, appropriate skeletal reconstruction, adequate skin cover and appropriate postoperative support and follow-up.

Detection of HIV-1 p24 Gag in plasma by a nanoparticle-based bio-barcode-amplification method

BACKGROUND

Detection of HIV-1 in patients is limited by the sensitivity and selectivity of available tests. The nanotechnology-based bio-barcode-amplification method offers an innovative approach to detect specific HIV-1 antigens from diverse HIV-1 subtypes. We evaluated the efficacy of this protein-detection method in detecting HIV-1 in men enrolled in the Chicago component of the Multicenter AIDS Cohort Study (MACS).

METHODS

The method relies on magnetic microparticles with antibodies that specifically bind the HIV-1 p24 Gag protein and nanoparticles that are encoded with DNA and antibodies that can sandwich the target protein captured by the microparticle-bound antibodies. The aggregate sandwich structures are magnetically separated from solution, and treated to remove the conjugated barcode DNA. The DNA barcodes (hundreds per target) were identified by a nanoparticle-based detection method that does not rely on PCR.

RESULTS

Of 112 plasma samples from HIV-1-infected subjects, 111 were positive for HIV-1 p24 Gag protein (range: 0.11-71.5 ng/ml of plasma) by the bio-barcode-amplification method. HIV-1 p24 Gag protein was detected in only 23 out of 112 men by the conventional ELISA. A total of 34 uninfected subjects were negative by both tests. Thus, the specificity of the bio-barcode-amplification method was 100% and the sensitivity 99%. The bio-barcode-amplification method detected HIV-1 p24 Gag protein in plasma from all study subjects with less than 200 CD4(+) T cells/microl of plasma (100%) and 19 out of 20 (95%) HIV-1-infected men who had less than 50 copies/ml of plasma of HIV-1 RNA. In a separate group of 60 diverse international isolates, representative of clades A, B, C and D and circulating recombinant forms CRF01_AE and CRF02_AG, the bio-barcode-amplification method identified the presence of virus correctly.

CONCLUSIONS

The bio-barcode-amplification method was superior to the conventional ELISA assay for the detection of HIV-1 p24 Gag protein in plasma with a breadth of coverage for diverse HIV-1 subtypes. Because the bio-barcode-amplification method does not require enzymatic amplification, this method could be translated into a robust point-of-care test.

High frequency of defective vpu compared with tat and rev genes in brain from patients with HIV type 1-associated dementia

Human immunodeficiency virus type 1 (HIV) infection of the central nervous system frequently causes HIV-associated dementia (HAD) and other neurological disorders. The role of HIV regulatory and accessory proteins in the pathogenesis of these disorders is unclear. Here we analyzed sequences of tat, rev, and vpu genes in 55 subgenomic clones previously shown to encode functional env genes from brain and lymphoid tissues of four AIDS patients with HAD. Phylogenetic analysis showed distinct compartmentalization of tat, rev, and vpu genes in brain versus lymphoid tissues. Nine of 19 vpu sequences from brain of two patients had premature stop codons at positions between amino acids 2 and 30, compared with 0 of 8 from lymphoid tissues. Tat sequences from brain (n = 8 of 8) but not lymphoid (n = 0 of 6) tissue from one patient had a 35 amino acid truncation at the C-terminus. Rev sequences from the brain of one patient (n = 6 of 8) had a 5 amino acid truncation. These results demonstrate a high frequency of defective vpu compared with tat and rev genes in brain from HAD patients, and identify sequence variants of these regulatory/accessory genes that may influence the pathogenesis of HIV-associated neurological disease.

Macrophage entry mediated by HIV Envs from brain and lymphoid tissues is determined by the capacity to use low CD4 levels and overall efficiency of fusion

HIV infects macrophages and microglia in the central nervous system (CNS), which express lower levels of CD4 than CD4+ T cells in peripheral blood. To investigate mechanisms of HIV neurotropism, full-length env genes were cloned from autopsy brain and lymphoid tissues from 4 AIDS patients with HIV-associated dementia (HAD). Characterization of 55 functional Env clones demonstrated that Envs with reduced dependence on CD4 for fusion and viral entry are more frequent in brain compared to lymphoid tissue. Envs that mediated efficient entry into macrophages were frequent in brain but were also present in lymphoid tissue. For most Envs, entry into macrophages correlated with overall fusion activity at all levels of CD4 and CCR5. gp160 nucleotide sequences were compartmentalized in brain versus lymphoid tissue within each patient. Proline at position 308 in the V3 loop of gp120 was associated with brain compartmentalization in 3 patients, but mutagenesis studies suggested that P308 alone does not contribute to reduced CD4 dependence or macrophage-tropism. These results suggest that HIV adaptation to replicate in the CNS selects for Envs with reduced CD4 dependence and increased fusion activity. Macrophage-tropic Envs are frequent in brain but are also present in lymphoid tissues of AIDS patients with HAD, and entry into macrophages in the CNS and other tissues is dependent on the ability to use low receptor levels and overall efficiency of fusion.

A real-time PCR-based method for determining the surface coverage of thiol-capped oligonucleotides bound onto gold nanoparticles

Here we report a real-time PCR-based method for determining the surface coverage of dithiol-capped oligonucleotides bound onto gold nanoparticles alone and in tandem with antibody. The detection of gold nanoparticle-bound DNA is accomplished by targeting the oligonucleotide with primer and probe binding sites, amplification of the oligonucleotide by PCR, and real-time measurement of the fluorescence emitted during the reaction. This method offers a wide dynamic range and is not dependant on the dissociation of the oligonucleotide strands from the gold nanoparticle surface; the fluorophore is not highly quenched by the gold nanoparticles in solution during fluorescence measurements. We show that this method and a fluorescence-based method give equivalent results for determining the surface coverage of oligonucleotides bound onto 13 or 30 nm gold nanoparticles alone and in tandem with antibody. Quantifying the surface coverage of immobilized oligonucleotides on metallic nanoparticle surfaces is important for optimizing the sensitivity of gold nanoparticle-based detection methods and for better understanding the interactions between thiol-functionalized oligonucleotides and gold nanoparticles.

Transcriptional Regulation of the HumanCD3γ Gene: The TATA-LessCD3γ Promoter Functions via an Initiator and Contiguous Sp-Binding Elements

Growing evidence that the CD3gamma gene is specifically targeted in some T cell diseases focused our attention on the need to identify and characterize the elusive elements involved in CD3gamma transcriptional control. In this study, we show that while the human CD3gamma and CD3delta genes are oriented head-to-head and separated by only 1.6 kb, the CD3gamma gene is transcribed from an independent but weak, lymphoid-specific TATA-less proximal promoter. Using RNA ligase-mediated rapid amplification of cDNA ends, we demonstrate that a cluster of transcription initiation sites is present in the vicinity of the primary core promoter, and the major start site is situated in a classical initiator sequence. A GT box immediately upstream of the initiator binds Sp family proteins and the general transcription machinery, with the activity of these adjacent elements enhanced by the presence of a second GC box 10 nt further upstream. The primary core promoter is limited to a sequence that extends upstream to -15 and contains the initiator and GT box. An identical GT box located approximately 50 nt from the initiator functions as a weak secondary core promoter and likely generates transcripts originating upstream from the +1. Finally, we show that two previously identified NFAT motifs in the proximal promoter positively (NFATgamma(1)) or negatively (NFATgamma(1) and NFATgamma(2)) regulate expression of the human CD3gamma gene by their differential binding of NFATc1 plus NF-kappaB p50 or NFATc2 containing complexes, respectively. These data elucidate some of the mechanisms controlling expression of the CD3gamma gene as a step toward furthering our understanding of how its transcription is targeted in human disease.

Renal dialysis: counting the cost versus counting the need

The relatively "lean and mean" provision of renal dialysis in Britain is a notorious example of "covert rationing", apparently achieved by a lack of central policy. Then in its first experiment in "target-setting" in the NHS in 1984, central government used the profession's preferred measure of need, thus promoting expansion of renal services, at almost exactly the time when the "quality-adjusted life year" (QALY) developed by health economists indicated that renal dialysis scored low in cost-benefit terms. This chapter examines these conundrums in terms of centre-periphery relations, clinical autonomy versus collective direction, and the politics of competing ways of counting need and cost.

Intensive care: measurement and audit in an expensive growth area of medicine

Intensive care historically shared with renal dialysis a relative shortfall in the UK and widely (wildly?) divergent provision in the regions. However, research on measurement of need was very different, with a focus on clinical audit. Priority was given to assessing how much the performance of different units could be attributed to differing intakes of patients through complex measuring tools such as the APACHE II score. While policy bodies welcomed this approach, policy guidelines in the 1990s relied most heavily on dissemination of "best practice", in any case raising standards through emulation within the UK rather than raising funding to European levels.

Structure and function of CC-chemokine receptor 5 homologues derived from representative primate species and subspecies of the taxonomic suborders Prosimii and Anthropoidea

A chemokine receptor from the seven-transmembrane-domain G-protein-coupled receptor superfamily is an essential coreceptor for the cellular entry of human immunodeficiency virus type 1 (HIV-1) and simian immunodeficiency virus (SIV) strains. To investigate nonhuman primate CC-chemokine receptor 5 (CCR5) homologue structure and function, we amplified CCR5 DNA sequences from peripheral blood cells obtained from 24 representative species and subspecies of the primate suborders Prosimii (family Lemuridae) and Anthropoidea (families Cebidae, Callitrichidae, Cercopithecidae, Hylobatidae, and Pongidae) by PCR with primers flanking the coding region of the gene. Full-length CCR5 was inserted into pCDNA3.1, and multiple clones were sequenced to permit discrimination of both alleles. Compared to the human CCR5 sequence, the CCR5 sequences of the Lemuridae, Cebidae, and Cercopithecidae shared 87, 91 to 92, and 96 to 99% amino acid sequence homology, respectively. Amino acid substitutions tended to cluster in the amino and carboxy termini, the first transmembrane domain, and the second extracellular loop, with a pattern of species-specific changes that characterized CCR5 homologues from primates within a given family. At variance with humans, all primate species examined from the suborder Anthropoidea had amino acid substitutions at positions 13 (N to D) and 129 (V to I); the former change is critical for CD4-independent binding of SIV to CCR5. Within the Cebidae, Cercopithecidae, and Pongidae (including humans), CCR5 nucleotide similarities were 95.2 to 97.4, 98.0 to 99.5, and 98.3 to 99.3%, respectively. Despite this low genetic diversity, the phylogeny of the selected primate CCR5 homologue sequences agrees with present primate systematics, apart from some intermingling of species of the Cebidae and Cercopithecidae. Constructed HOS.CD4 cell lines expressing the entire CCR5 homologue protein from each of the Anthropoidea species and subspecies were tested for their ability to support HIV-1 and SIV entry and membrane fusion. Other than that of Cercopithecus pygerythrus, all CCR5 homologues tested were able to support both SIV and HIV-1 entry. Our results suggest that the shared structure and function of primate CCR5 homologue proteins would not impede the movement of primate immunodeficiency viruses between species.

Emergence of cytotoxic T lymphocyte escape mutants following antiretroviral treatment suspension in rhesus macaques infected with SIVmac251

Structured treatment interruption (STI) of antiretroviral drugs has been proposed as an alternative approach for managing patients infected with HIV-1. While STI is thought to spare drug-related side effects and enhance the HIV-1-specific immune response, the long-lasting clinical benefit of this approach remains uncertain, particularly in patients with long-standing HIV-1 infection. Here, we investigated the basis of unabated virological replication following different STI regimens in rhesus macaques that expressed the MHC class I Mamu-A*01 molecule treated during acute and long-standing infection with SIVmac251. An amino acid change at the anchor residue within the immunodominant Mamu-A*01-restricted Gag(181-189) CM9 epitope (T --> A) in one of six macaques with acute SIVmac251 infection and in three of four macaques with long-standing SIVmac251 infection (T --> A; T --> S; S --> C) was found in the majority of plasma virus. These amino acid changes have been shown to severely decrease binding of the corresponding peptides to the Mamu-A*01 molecule and, in the case of the T --> A change, escape from CTL. In one macaque with long-standing SIVmac251 infection, a mutation emerged that conferred resistance to one of the antiretroviral drugs (PMPA) as well. These results provide insights into the mechanism underlying the limited capacity of repeated interruption of antiretroviral therapy as an approach to restrain viral replication. In addition, these data also suggest that interruption of therapy may be less effective in chronic infection because of preexisting immune escape and that immune escape is a risk of interruption of therapy.

Inability to consistently elicit a motor response following sensory paresthesia during interscalene block administration

BACKGROUND

Two methods of nerve block based on eliciting neural feedback with the block needle currently exist. The paresthesia technique uses sensory feedback to ascertain that the needle tip is close to the nerve. By contrast, a peripheral nerve stimulator makes use of motor responses to electrical stimulation. The relation of motor responses to an electrical peripheral nerve stimulator and sensory nerve contact (paresthesia) had not been studied.

METHODS

Thirty consecutive unpremedicated patients who presented for shoulder surgery with interscalene block anesthesia were prospectively studied. Interscalene block was performed by the single paresthesia method of Winnie, using an insulated or non-insulated needle connected to a peripheral nerve stimulator with the power off. At the precise point of paresthesia, the peripheral nerve stimulator was turned on, and the current was slowly increased to 1.0 mA with a pulse width of 0.2 ms. Presence and location of any motor responses were observed and recorded.

RESULTS

All patients had easily elicited paresthesias. The site of first paresthesia was to the shoulder in 73% of patients. Only 30% of patients exhibited any motor response to electrical stimulation up to 1.0 mA. There was no relation between site of paresthesia and associated motor nerve response.

CONCLUSION

Elicitation of paresthesia does not translate to an ability to elicit a motor response to a peripheral nerve stimulator in the majority of patients.

Murder misdiagnosed as SIDS: a perpetrator's perspective

AIMS

Child murder misdiagnosed as sudden infant death syndrome (SIDS) is a difficult area to study. We present a perpetrator's descriptions to enrich clinicians' knowledge of possible presenting features of this phenomenon.

METHODS

Interview material was collected as part of a qualitative study of maternal filicide performed from a naturalistic paradigm in order to access the perpetrators' view of events. The woman participant has been convicted for three child murders and two attempted murders which were initially misdiagnosed as SIDS. Interviews were done in the participant's home with her partner present, while she was on leave from prison. Semi-structured interviews were conducted, recorded, transcribed, and analysed for themes. Specific ethical permission was gained to present this case in isolation and the paper was written in consultation with the woman described.

RESULTS

She described initial intense attachment to her first victim and described killing her because she was unable to bear her apnoea attacks and her fear of losing her. She described difficulty grieving for this child and subsequent failure to attach to her next child or feel for the other victims.

CONCLUSIONS

Expressions of intense attachment to an infant and description of intense grief over a death in a way which engages compassion should not deter a paediatrician from considering the possibility of the parent having killed the child.

A nurse's aid to clinical selection of pressure-reducing equipment

The selection of appropriate pressure-relieving equipment for individuals in the community is an important process in the prevention of pressure ulcers. The clinical decision is made by community nurses who are accountable for their actions and who therefore have to have clear rationale for the decisions they make. Risk tools are not a completely reliable or valid method of assessing patients. The current national guidelines (National Institute for Clinical Excellence (NICE), 2001) are not specific in relation to the selection or choice of equipment. This article explores how these decisions are made.

A truly hybrid interventional MR/X-ray system: feasibility demonstration

A system enabling both x-ray fluoroscopy and MRI in a single exam, without requiring patient repositioning, would be a powerful tool for image-guided interventions. We studied the technical issues related to acquisition of x-ray images inside an open MRI system (GE Signa SP). The system includes a flat-panel x-ray detector (GE Medical Systems) placed under the patient bed, a fixed-anode x-ray tube overhead with the anode-cathode axis aligned with the main magnetic field and a high-frequency x-ray generator (Lunar Corp.). New challenges investigated related to: 1) deflection and defocusing of the electron beam of the x-ray tube; 2) proper functioning of the flat panel; 3) effects on B0 field homogeneity; and 4) additional RF noise in the MR images. We have acquired high-quality x-ray and MR images without repositioning the object using our hybrid system, which demonstrates the feasibility of this new configuration. Further work is required to ensure that the highest possible image quality is achieved with both MR and x-ray modalities.

A qualitative study of filicide by mentally ill mothers

OBJECTIVE

To examine descriptions of maternal filicide committed in the context of major mental illness from the frame of reference of a group of perpetrators.

METHOD

Participants were accessed via their treating psychiatrists. A naturalistic paradigm was used. Semi-structured individual interviews were audio-taped and transcribed. Theme analysis of the transcripts was done by repeated reading of transcripts and coding utterances, individually, then jointly by the authors.

RESULTS

Six women were identified, and interviewed. They described intense investment in mothering their child(ren). Descriptions of external stressors were not extreme, but the experience of illness was described as extremely stressful. They described little or no warning or planning. Their descriptions of their children were unremarkable. Motivation was described as altruistic or as an extension of suicide. They described regretting the killings and feeling responsible even though they knew they had been ill at the time.

CONCLUSIONS

The findings underline the difficulty of identification of risk and prevention of maternally ill filicide in the women who described being very caring towards their children, and little or no warning of filicidal urges. They may be better understood in terms of the illness than individual stress or psychodynamics.

Kinematics of the wrist. Evidence for two types of movement

We enrolled 34 normal volunteers to test the hypothesis that there were two types of movement of the wrist. On lateral radiographs two distinct patterns of movement emerged. Some volunteers showed extensive rotation of the lunate with a mean range of dorsiflexion of 65 degrees, while others had a mean range of 50 degrees. The extensive rotators were associated with a greater excursion of the centre of articulation of the wrist. It is suggested that dynamic external fixation of a fracture of the distal radius carries with it the risk of stretching the ligaments or causing volar displacement at the site of the fracture.

Double-blind randomized controlled trial of glutamine-enriched polymeric diet in the treatment of active Crohn's disease

BACKGROUND

Glutamine is traditionally considered a nonessential amino acid but may be conditionally essential in patients with catabolic conditions. Glutamine-supplemented foods in these patients have been shown to prevent deterioration of gut permeability, protect against the development of intestinal mucosal atrophy, and improve nitrogen balance. Animal models of inflammatory bowel disease suggest that glutamine-enriched enteral diets may lead to less severe intestinal damage, less weight loss, improved nitrogen balance, and reduced disease activity. The purpose of the current study was to compare the efficacy of a glutamine-enriched polymeric diet with a standard low-glutamine polymeric diet in the treatment of active Crohn's disease.

METHODS

Eighteen children with active Crohn's disease were randomly assigned to receive a 4-week course of either a standard polymeric diet with a low glutamine content (4% of amino acid composition; group S) or a glutamine-enriched polymeric diet (42% of amino acid composition; Group G). The two diets were isocaloric and isonitrogenous with an identical essential amino acid profile. Remission rates were analysed on an intent-to-treat basis. Changes in clinical and laboratory parameters of disease activity were also compared after 4 weeks of nutritional treatment.

RESULTS

Two of the children, both in group G, were withdrawn from the trial because of nontolerance of the diet. There was no difference between the two groups in proportion of patients achieving remission (intent-to-treat basis): 5 (55.5%) of 9 in group S versus 4 (44.4%) of 9 in group G (p = 0.5). Improvement in mean paediatric Crohn's disease activity index (PCDAI) was significantly more in group S (p = 0.002) but changes in orosomucoid level, platelet count, and weight were not different between the groups.

CONCLUSIONS

The findings suggest that a glutamine-enriched polymeric diet offers no advantage over a standard low-glutamine polymeric diet in the treatment of active Crohn's disease. Rather, it appears to be less effective in improving PCDAI. The reported beneficial effects of glutamine seen in many catabolic states must be viewed with caution when extrapolating to the management of Crohn's disease.

The cost of living: kidney dialysis, rationing and health economics in Britain, 1965-1996

How important is research in shaping policy when a new life-saving medical technology becomes available, but happens to be very expensive? Taking the case of kidney dialysis, this paper argues that the emerging discipline of health economics had little influence relative to national differences in health service organization and cultures of expectation of provision. Paradoxically, the most effective covert rationing was achieved under the British NHS which ostensibly provides free care for all, while the uncentralised market system in the US gave way, on this issue, to almost universal state-subsidised provision. Under the British system, the most cost-effective options for renal care tended to flourish, but some patients were turned away. Physicians have been held responsible for complying with covert rationing: this paper suggests that early gearing towards socially-useful survival filtered back to selection at primary level, possibly continuing long after specialists wished to expand. Public outcry, though muted, reached parliament and caused minor shifts in policy; the main aim of the voluntary pressure campaign, to release more organs for transplant through 'opt-out', remained unrealised in the UK. Yet dialysis was targetted for expansion in the 1980s just at the point when health economists were presenting evidence for its low cost-effectiveness compared with other expensive interventions. According to the main strand of argument in this paper, comparisons with other countries and between regions were most influential in breaking the hold of covert rationing: policy making by embarrassment. However, in the 1990s, there are both theoretical discussions of explicit rationing, and open intiatives afoot to target dialysis for rationing.

Reticulate evolution and the origins of ribosomal internal transcribed spacer diversity in apomictic Meloidogyne

Among root knot nematodes of the genus Meloidogyne, the polyploid obligate mitotic parthenogens M. arenaria, M. javanica, and M. incognita are widespread and common agricultural pests. Although these named forms are distinguishable by closely related mitochondrial DNA (mtDNA) haplotypes, detailed sequence analyses of internal transcribed spacers (ITSs) of nuclear ribosomal genes reveal extremely high diversity, even within individual nematodes. This ITS diversity is broadly structured into two very different groups that are 12%-18% divergent: one with low diversity (< 1.0%) and one with high diversity (6%-7%). In both of these groups, identical sequences can be found within individual nematodes of different mtDNA haplotypes (i.e., among species). Analysis of genetic variance indicates that more than 90% of ITS diversity can be found within an individual nematode, with small but statistically significant (5%-10%; P < 0.05) variance distributed among mtDNA lineages. The evolutionarily distinct parthenogen M. hapla shows a similar pattern of ITS diversity, with two divergent groups of ITSs within each individual. In contrast, two diploid amphimictic species have only one lineage of ITSs with low diversity (< 0.2%). The presence of divergent lineages of rDNA in the apomictic taxa is unlikely to be due to differences among pseudogenes. Instead, we suggest that the diversity of ITSs in M. arenaria, M. javanica, and M. incognita is due to hybrid origins from closely related females (as inferred from mtDNA) and combinations of more diverse paternal lineages.

APOE is linked to Alzheimer's disease in a large pedigree

Although previous association studies have demonstrated that the APOE4 allele is a risk factor for Alzheimer's disease (AD), its value for the prediction of AD in individuals is <100%. The limited predictive value of epsilon4 is also seen in multiply affected families where the epsilon4 allele is not tightly linked to AD. We analyzed a large pedigree multiply affected with AD by lod score linkage analysis at the known loci associated with AD. In this pedigree, the APOE/APOCI gene area was linked to the development of AD, while no linkage was detected to any of the other loci known to be associated with the disease. In this family, then, the inheritance of an epsilon4 allele is highly associated with the early development of the disease (mean age of onset, 62 years), and is a good predictor of disease. However, given the wealth of evidence for association, but not linkage, of APOE4 to AD, we believe this finding suggests that another factor (or factors) interact(s) with APOE to precipitate early disease, and produce positive linkage results. The nature of this factor presently remains unknown.

No association between the intronic presenilin-1 polymorphism and Alzheimer's disease in clinic and population-based samples

Mutations in the Presenilin 1 (PS1) gene on chromosome 14 cause most early-onset familial Alzheimer's disease (AD). An intronic polymorphism in the PS1 gene was recently identified and reported to be associated with late-onset AD [Wragg et al., Lancet 347: 509-512, 1996]. The authors found an excess of homozygotes for the more common allele (allele 1) in AD cases, associated with an approximate doubling of risk. In the present study, we report the PS1 polymorphism distributions in clinic and population-based samples. We were not able to replicate the findings of Wragg et al. [1996]. Our results are consistent with those of other researchers and do not support the conclusion that the PS1 polymorphism is associated with late-onset AD.

The direction of the Whitacre needle aperture affects the extent and duration of isobaric spinal anesthesia

The use of Whitacre spinal needles results in directional flow out of the needle aperture, diverting local anesthetic from the longitudinal axis of the needle. Thus, a change in orientation of the needle aperture would be expected to result in a different local anesthetic distribution in the subarachnoid space. We studied 40 outpatients undergoing elective knee arthroscopy under spinal anesthesia with 60 mg plain lidocaine 2% in a prospective, double-blinded manner. Patients were randomly assigned to either Group I (needle aperture oriented in a cephalad direction throughout intrathecal injection) or Group II (aperture directed caudally). Onset and offset of sensory and motor block were analyzed at frequent intervals. Times to completion of ambulatory milestones, including discharge, were recorded. Group I was characterized by a higher sensory level (T 3.4 +/- 1.3 vs T 6.6 +/- 2.8, P < 0.001). Group I had significantly shorter duration of lumbar sensory anesthesia (149.2 +/- 30.6 min vs 177.8 +/- 23.5 min, P < 0.01) and motor blockade (117.6 +/- 26.1 min vs 150.0 +/- 22.8 min, P < 0.001). Mean time to outpatient discharge was approximately 32 min shorter in Group I. The orientation of the Whitacre needle aperture exerts a major influence on sensory level, as well as the duration of isobaric lidocaine spinal anesthesia.

Evolution of the AT-rich mitochondrial DNA of the root knot nematode, Meloidogyne hapla

Mitochondrial DNA of the root knot nematode Meloidogyne hapla was investigated for intraspecific diversity and divergence from other parthenogenetic root knot nematodes. A 1,900-bp fragment containing COII, tRNAHis, 16S rRNA, ND3 and Cyt b genes has been cloned and sequenced from one individual and an 1,188-bp region within this region was sequenced from four other Australian isolates. M. hapla mtDNA is more than 80% AT-rich, like other Meloidogyne spp. Nucleotide diversity within M. hapla is some 10-fold higher than across three other parthenogenetic species of root-knot nematode (M. arenaria, M. javanica, and M. incognita), implying an earlier origin for M. hapla. Nucleotide divergence between M. hapla and its congener M. javanica is as great as that between Ascaris suum and Caenorhabditis elegans, members of different nematode subclasses, while amino acid sequence difference between Meloidogyne is more than twice as great. This is interpreted as an AT-bias-induced acceleration of the amino acid substitution rate, over and above saturation of nucleotide divergence in the strongly AT-biased DNA, on three lines of evidence: (1) in conserved blocks in 16S rDNA congeneric Meloidogyne have no more differences than between A. suum and C. elegans; (2) the Meloidogyne lineage has more amino acid changes relative to the Ascaris/Caenorhabditis lineage with respect to four of five outgroups, the exceptional outgroup being the only species (Apis) as AT-rich as Meloidogyne; and (3) between the two Meloidogyne there are more first and second but fewer third codon position changes than between the other nematode species. M. hapla is also found to contain a 102-bp tandem repeat of at least 40 copies; a size, arrangement, and position the same as in M. javanica, but sequence comparisons did not demonstrate homology between the two repeats.

Digital pressure during interscalene block is clinically ineffective in preventing anesthetic spread to the cervical plexus

The application of digital pressure above the injection site during interscalene block has been advocated to prevent cephalad spread of local anesthetic. In prior studies, radiographs taken immediately after interscalene injection of radiographic contrast have supported this concept. However, the clinical efficacy of digital pressure has not been previously tested. If digital pressure were effective in inhibiting cephalad spread of local anesthetic, attenuation of both hemidiaphragmatic paresis and the resulting compromise in pulmonary function would be expected. Sensory, motor, and pulmonary effects were prospectively evaluated in 20 patients presenting for elective shoulder surgery. Patients were randomly assigned to receive interscalene block with or without digital pressure. No clinical differences were seen between groups. All 20 patients had ipsilateral hemidiaphragmatic paresis by ultrasonographic evaluation and large mean decreases in forced vital capacity, 31.2% +/- 7.8% (with digital pressure), 33.7% +/- 12.8% (without digital pressure), and forced expiratory volume at one second, 27.9% +/- 9.3% (with digital pressure), 33.7 +/- 12.8% (without digital pressure). Peak sensory level of anesthesia to pinprick was not significantly different between groups, each group having mean levels of C-2 to C-3. Digital pressure was ineffective in limiting the flow of local anesthetic into the cervical plexus. Digital pressure influenced neither the incidence of diaphragmatic paresis nor the resulting large decreases in pulmonary function that result from interscalene block.

Combined spinal-epidural anesthesia for outpatient surgery. Dose-response characteristics of intrathecal isobaric lidocaine using a 27-gauge Whitacre spinal needle

BACKGROUND

Combined spinal-epidural anesthesia (CSE) may offer theoretic advantages for outpatient surgery, because it produces the rapid onset of spinal anesthesia, with the option to extend the blockade with an epidural catheter. In this study, the authors attempted to determine an appropriate initial dose of a short-acting local anesthetic, 2% lidocaine, to administer for outpatient knee arthroscopy using CSE.

METHODS

Data were collected from 90 patients undergoing outpatient knee arthroscopy. Using a double-blinded, prospective study design, patients were randomly assigned to receive CSE with an initial dose of intrathecal 2% lidocaine of 40, 60, or 80 mg. A 27-G 4 11/16-inch Whitacre needle was placed through a 17-G Weiss needle. Onset and regression of sensory anesthesia and motor blockade were measured by a blinded observer at frequent intervals.

RESULTS

All 90 patients had adequate anesthesia. Durations of thoracic and lumbar sensory and lower limb motor blockade were significantly shorter in the 40-mg group compared with the 60- or 80-mg groups (P < 0.0002 Mantel-Cox, Survivorship Analysis). Indices of neural blockade resolved 30-40 min more rapidly in the 40-mg group than in either the 60- or 80-mg group. Times to urinate, site upright in a chair, take oral fluids, and be discharged were all significantly shorter (between 30 and 60 min) in the 40-mg group compared with the 60- and 80-mg groups (P < 0.01). Seven patients required intraoperative epidural supplementation: three in the 40-mg group, three in the 60-mg group, and one in the 80-mg group.

CONCLUSIONS

Combined spinal-epidural anesthesia with a 40-mg initial intrathecal dose of lidocaine provided reliable anesthesia for knee arthroscopy. Duration of spinal anesthesia with lidocaine was dose related.