Chinese family care partners of older adults in Canada have grit: A qualitative study

AIM

To explain the process taken by Chinese family care partners of older adults in the Greater Toronto Area, Canada, to access health and social services in their communities. The research question was: What mechanisms and structures impact the agency of Chinese family care partners of older adults, in the process of assisting them to access health and social services?

DESIGN

This qualitative study was informed by critical realism.

METHODS

Chinese family care partners of older adults in the Greater Toronto Area, Canada, were interviewed from August 2020 to June 2021. Transcripts underwent thematic analysis.

FINDINGS

Twenty-eight Chinese family care partners expressed a firm commitment to maintain caregiving conditions and to judiciously access health and social services. Their commitment was made up of three parts: (a) legislative and cultural norms of family, work, and society; (b) their perseverance to fill gaps with limited social and financial resources; (c) the quality of their relationship to, and illness trajectory of the older adults. The social structures created tension in how Chinese family care partners made decisions, negotiated resources, and ultimately monitored and coordinated timely access with older adults.

CONCLUSION

Participants' commitment and perseverance were conceptualized as "grit," central to their agency to conform to legislative and cultural norms. Moreover, findings support grit's power to motivate and sustain family caregiving, in order for older adults to age in place as long as possible with finite resources.

IMPLICATIONS FOR THE PROFESSION

This study highlights the importance of cultural awareness education for nurses, enabling continuity of care at a systems level and for a more resilient healthcare system.

IMPACT

Family care partners' grit may be crucial for nurses to harness when together, they face limited access to culturally appropriate health and social services in a system grounded in values of equity and inclusion, as in Canada.

REPORTING METHOD

When writing this manuscript, we adhered to relevant EQUATOR guidelines of the Consolidated Criteria for Reporting Qualitative Research (COREQ).

PATIENT OR PUBLIC INVOLVEMENT AND ENGAGEMENT

No patient or public involvement.

Estimating the prognostic value of cross-sectional network connectivity for treatment response in depression

BACKGROUND

Tightly connected symptom networks have previously been linked to treatment resistance, but most findings come from small-sample studies comparing single responder v. non-responder networks. We aimed to estimate the association between baseline network connectivity and treatment response in a large sample and benchmark its prognostic value against baseline symptom severity and variance.

METHODS

N = 40 518 patients receiving treatment for depression in routine care in England from 2015-2020 were analysed. Cross-sectional networks were constructed using the Patient Health Questionnaire-9 (PHQ-9) for responders and non-responders (N = 20 259 each). To conduct parametric tests investigating the contribution of PHQ-9 sum score mean and variance to connectivity differences, networks were constructed for 160 independent subsamples of responders and non-responders (80 each, n = 250 per sample).

RESULTS

The baseline non-responder network was more connected than responders (3.15 v. 2.70, S = 0.44, p < 0.001), but effects were small, requiring n = 750 per group to have 85% power. Parametric analyses revealed baseline network connectivity, PHQ-9 sum score mean, and PHQ-9 sum score variance were correlated (r = 0.20-0.58, all p < 0.001). Both PHQ-9 sum score mean (β = -1.79, s.e. = 0.07, p < 0.001), and PHQ-9 sum score variance (β = -1.67, s.e. = 0.09, p < 0.001) had larger effect sizes for predicting response than connectivity (β = -1.35, s.e. = 0.12, p < 0.001). The association between connectivity and response disappeared when PHQ-9 sum score variance was accounted for (β = -0.28, s.e. = 0.19, p = 0.14). We replicated these results in patients completing longer treatment (8-12 weeks, N = 22 952) and using anxiety symptom networks (N = 70 620).

CONCLUSIONS

The association between baseline network connectivity and treatment response may be largely due to differences in baseline score variance.

Elevated emotion network connectivity is associated with fluctuations in depression

Elevated emotion network connectivity is thought to leave people vulnerable to become and stay depressed. The mechanism through which this arises is however unclear. Here, we test the idea that the connectivity of emotion networks is associated with more extreme fluctuations in depression over time, rather than necessarily more severe depression. We gathered data from two independent samples of N = 155 paid students and N = 194 citizen scientists who rated their positive and negative emotions on a smartphone app twice a day and completed a weekly depression questionnaire for 8 wk. We constructed thousands of personalized emotion networks for each participant and tested whether connectivity was associated with severity of depression or its variance over 8 wk. Network connectivity was positively associated with baseline depression severity in citizen scientists, but not paid students. In contrast, 8-wk variance of depression was correlated with network connectivity in both samples. When controlling for depression variance, the association between connectivity and baseline depression severity in citizen scientists was no longer significant. We replicated these findings in an independent community sample (N = 519). We conclude that elevated network connectivity is associated with greater variability in depression symptoms. This variability only translates into increased severity in samples where depression is on average low and positively skewed, causing mean and variance to be more strongly correlated. These findings, although correlational, suggest that while emotional network connectivity could predispose individuals to severe depression, it could also be leveraged to bring about therapeutic improvements.

An observational treatment study of metacognition in anxious-depression

Prior studies have found metacognitive biases are linked to a transdiagnostic dimension of anxious-depression, manifesting as reduced confidence in performance. However, previous work has been cross-sectional and so it is unclear if under-confidence is a trait-like marker of anxious-depression vulnerability, or if it resolves when anxious-depression improves. Data were collected as part of a large-scale transdiagnostic, four-week observational study of individuals initiating internet-based cognitive behavioural therapy (iCBT) or antidepressant medication. Self-reported clinical questionnaires and perceptual task performance were gathered to assess anxious-depression and metacognitive bias at baseline and 4-week follow-up. Primary analyses were conducted for individuals who received iCBT (n=649), with comparisons between smaller samples that received antidepressant medication (n=82) and a control group receiving no intervention (n=88). Prior to receiving treatment, anxious-depression severity was associated with under-confidence in performance in the iCBT arm, replicating previous work. From baseline to follow-up, levels of anxious-depression were significantly reduced, and this was accompanied by a significant increase in metacognitive confidence in the iCBT arm (β=0.17, SE=0.02, p<0.001). These changes were correlated (r(647)=-0.12, p=0.002); those with the greatest reductions in anxious-depression levels had the largest increase in confidence. While the three-way interaction effect of group and time on confidence was not significant (F(2, 1632)=0.60, p=0.550), confidence increased in the antidepressant group (β=0.31, SE = 0.08, p<0.001), but not among controls (β=0.11, SE = 0.07, p=0.103). Metacognitive biases in anxious-depression are state-dependent; when symptoms improve with treatment, so does confidence in performance. Our results suggest this is not specific to the type of intervention.

The Effectiveness of Low-Intensity Psychological Interventions for Comorbid Depression and Anxiety in Patients with Long-Term Conditions: A Real-World Naturalistic Observational Study in IAPT Integrated Care

BACKGROUND

Low-intensity psychological interventions may be a cost-effective, accessible solution for treating depression and anxiety in patients with long-term conditions, but evidence from real-world service settings is lacking. This study examined the effectiveness of low-intensity psychological interventions provided in the Improving Access to Psychological Therapies programme in England for patients with and without long-term conditions.

METHODS

A retrospective analysis was conducted on patients (total N = 21,051, long-term conditions n = 4024) enrolled in three low-intensity psychological interventions, i.e. Internet-delivered cognitive behavioural therapy (iCBT), guided self-help (GSH), and psychoeducational group therapy (PGT) within a Talking Therapies service from 2016 to 2020. Primary outcomes included pre-post-treatment changes in depression (Patient Health Questionnaire-9) and anxiety (Generalised Anxiety Disorder-7).

RESULTS

Overall, both cohorts significantly improved on all outcomes post-treatment, with large effect sizes. Patients with long-term conditions experienced a greater reduction in depression while those without experienced a greater reduction in anxiety, but these differences were marginal (< 1 score difference on both measures). No difference between the cohorts was shown when comparing the differential effectiveness across interventions, but those engaging in iCBT showed greater reduction in depression and anxiety than those in GSH and PGT, while those in GSH improved more than PGT.

CONCLUSIONS

Low-intensity psychological interventions, particularly iCBT, were effective in treating depression and anxiety in patients with long-term conditions in a real-world service setting. Our large-scale study supports the continued and increased implementation of low-intensity psychological interventions for this subpopulation via integrated care.

The Precision in Psychiatry (PIP) study: Testing an internet-based methodology for accelerating research in treatment prediction and personalisation

BACKGROUND

Evidence-based treatments for depression exist but not all patients benefit from them. Efforts to develop predictive models that can assist clinicians in allocating treatments are ongoing, but there are major issues with acquiring the volume and breadth of data needed to train these models. We examined the feasibility, tolerability, patient characteristics, and data quality of a novel protocol for internet-based treatment research in psychiatry that may help advance this field.

METHODS

A fully internet-based protocol was used to gather repeated observational data from patient cohorts receiving internet-based cognitive behavioural therapy (iCBT) (N = 600) or antidepressant medication treatment (N = 110). At baseline, participants provided > 600 data points of self-report data, spanning socio-demographics, lifestyle, physical health, clinical and other psychological variables and completed 4 cognitive tests. They were followed weekly and completed another detailed clinical and cognitive assessment at week 4. In this paper, we describe our study design, the demographic and clinical characteristics of participants, their treatment adherence, study retention and compliance, the quality of the data gathered, and qualitative feedback from patients on study design and implementation.

RESULTS

Participant retention was 92% at week 3 and 84% for the final assessment. The relatively short study duration of 4 weeks was sufficient to reveal early treatment effects; there were significant reductions in 11 transdiagnostic psychiatric symptoms assessed, with the largest improvement seen for depression. Most participants (66%) reported being distracted at some point during the study, 11% failed 1 or more attention checks and 3% consumed an intoxicating substance. Data quality was nonetheless high, with near perfect 4-week test retest reliability for self-reported height (ICC = 0.97).

CONCLUSIONS

An internet-based methodology can be used efficiently to gather large amounts of detailed patient data during iCBT and antidepressant treatment. Recruitment was rapid, retention was relatively high and data quality was good. This paper provides a template methodology for future internet-based treatment studies, showing that such an approach facilitates data collection at a scale required for machine learning and other data-intensive methods that hope to deliver algorithmic tools that can aid clinical decision-making in psychiatry.

Assessing the Efficacy and Acceptability of a Web-Based Intervention for Resilience Among College Students: Pilot Randomized Controlled Trial

BACKGROUND

College students are at elevated risk for developing mental health problems and face specific barriers around accessing evidence-based treatment. Web-based interventions that focus on mental health promotion and strengthening resilience represent one possible solution. Providing support to users has shown to reduce dropout in these interventions. Further research is needed to assess the efficacy and acceptability of these interventions and explore the viability of automating support.

OBJECTIVE

This study investigated the feasibility of a new web-based resilience program based on positive psychology, provided with human or automated support, in a sample of college students.

METHODS

A 3-armed closed pilot randomized controlled trial design was used. Participants were randomized to the intervention with human support (n=29), intervention with automated support (n=26), or waiting list (n=28) group. Primary outcomes were resilience and well-being, respectively measured by the Connor-Davidson Resilience Scale and Pemberton Happiness Index. Secondary outcomes included measures of depression and anxiety, self-esteem, and stress. Outcomes were self-assessed through online questionnaires. Intention-to-treat and per-protocol analyses were conducted.

RESULTS

All participants demonstrated significant improvements in resilience and related outcomes, including an unexpected improvement in the waiting list group. Within- and between-group effect sizes ranged from small to moderate and within-group effects were typically larger for the human than automated support group. A total of 36 participants began the program and completed 46.46% of it on average. Participants were generally satisfied with the program and found it easy to use.

CONCLUSIONS

Findings support the feasibility of the intervention. Preliminary evidence for the equal benefit of human and automated support needs to be supported by further research with a larger sample. Results of this study will inform the development of a full-scale trial, from which stronger conclusions may be drawn.

TRIAL REGISTRATION

International Standard Randomized Controlled Trial Number (ISRCTN) 11866034; http://www.isrctn.com/ISRCTN11866034.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR2-10.1016/j.invent.2019.100254.

Factors associated with food insecurity among older homeless adults: results from the HOPE HOME study

BACKGROUND

The US homeless population is aging. Older adults and those living in poverty are at a high risk of food insecurity.

METHODS

We conducted a cross-sectional analysis of baseline data from a population-based study of 350 homeless adults aged ≥50. We assessed food security and receipt of food assistance. We used multivariable logistic regression to examine factors associated with very low food security.

RESULTS

The majority of the cohort was male and African American. Over half (55.4%) met criteria for food insecurity, 24.3% reported very low food security. Half (51.7%) reported receiving monetary food assistance. In the multivariable model, those who were primarily sheltered in the prior 6 months, (multi-institution users [AOR = 0.44, 95% CI: 0.22-0.86]) had less than half the odds of very low food security compared with those who were unsheltered. Depressive symptoms (AOR = 3.01, 1.69-5.38), oral pain (AOR = 2.15, 1.24-3.74) and cognitive impairment (AOR = 2.21, 1.12-4.35) were associated with increased odds of very low food security.

CONCLUSIONS

Older homeless adults experience a high prevalence of food insecurity. To alleviate food insecurity in this population, targeted interventions must address specific risk groups.

Fetal Development: Voice Processing in Normotensive and Hypertensive Pregnancies

Recent observation of maternal voice recognition provides evidence of rudimentary memory and learning in healthy term fetuses. However, such higher order auditory processing has not been examined in the presence of maternal hypertension, which is associated with reduced and/or impaired uteroplacental blood flow. In this study, voice processing was examined in 40 fetuses (gestational ages of 33 to 41 weeks) of hypertensive and normotensive women. Fetuses received 2 min of no sound, 2 min of a tape-recorded story read by their mothers or by a female stranger, and 2 min of no sound while fetal heart rate was recorded. Results demonstrated that fetuses in the normotensive group had heart rate accelerations during the playing of their mother's voice, whereas the response occurred in the hypertensive group following maternal voice offset. Across all fetuses, a greater fetal heart rate change was observed when the amniotic fluid index was above compared to below the median (i.e., 150 mm), indicating that amniotic fluid volume may be an independent moderator of fetal auditory sensitivity. It was concluded that differential fetal responding to the mother's voice in pregnancies complicated by maternal hypertension may reflect functional elevation of sensorineural threshold or a delay in auditory system maturation, signifying functional differences during fetal life or subtle differences in the development of the central nervous system.

Pursuing Quality in the Application of Bladder Cancer Quality of Life Research

Patient-reported outcomes (PRO), including health-related quality of life (HRQOL) measures, represent important means for evaluating patients' health outcomes and for guiding health care decisions made by patients, practitioners, investigators, and policy makers. In spite of the large number of studies examining HRQOL in patients with bladder cancer, very few review articles investigated this topic. Because these review studies report mixed results, incorporating bladder cancer HRQOL measures into standard urological practice is not a viable option. In this non-systematic review of the literature and commentary we note some general concerns regarding PRO research, but our primary focus is on the HRQOL methodology within the context of two types of bladder cancer: muscle invasive and non-muscle invasive bladder cancer. Considering bladder cancer HRQOL as the interaction of four areas of the assessment process (i.e., what model of HRQOL to choose, what instruments are available to fit the choice, how interpretation of the resulting data fits the model, and how to derive some utility from the chosen model) and the two types of disease (i.e., muscle invasive and non-muscle invasive) may move us toward a better understanding of bladder cancer HRQOL. Establishing a useful model of perceived general health or specific symptoms is the first and most important step in developing the responsive bladder cancer HRQOL measures necessitated by clinical settings.

Clinicopathologic and prognostic significance of c-MYC copy number gain in lung adenocarcinomas

BACKGROUND

c-MYC copy number gain (c-MYC gain) has been associated with aggressive behaviour in several cancers. However, the role of c-MYC gain has not yet been determined in lung adenocarcinomas classified by genetic alterations in epidermal growth factor receptor (EGFR), KRAS, and anaplastic lymphoma kinase (ALK) genes. We investigated the clinicopathologic and prognostic significance of c-MYC gain for disease-free survival (DFS) and overall survival (OS) according to EGFR, KRAS, and ALK gene status and stages in lung adenocarcinomas.

METHODS

In 255 adenocarcinomas resected in Seoul National University Bundang Hospital from 2003 to 2009, fluorescence in situ hybridisation (FISH) with c-MYC probe and centromeric enumeration probe 8 (CEP8) was analysed using tissue microarray containing single representative core per each case. EGFR (codon 18 to 21) and KRAS (codon 12, 13, and 61) mutations were analysed by polymerase chain reaction and direct sequencing method from formalin-fixed, paraffin-embedded tissue sections. ALK rearrangement was determined by FISH method. c-MYC gain was defined as >2 copies per nucleus, chromosome 8 gain as ⩾3 copies per nucleus, and gain of c-MYC:CEP8 ratio (hereafter, c-MYC amplification) as ⩾2.

RESULTS

We observed c-MYC gain in 20% (51 out of 255), chromosome 8 gain in 5.5% (14 out of 255), c-MYC amplification in 2.4% (6 out of 255), EGFR mutation in 49.4% (118 out of 239), KRAS mutation in 5.7% (7 out of 123), and ALK rearrangement in 4.9% (10 out of 205) of lung adenocarcinomas. c-MYC gain was observed in 19% (22 out of 118) of patients with lung adenocarcinomas with an EGFR mutation, but not in any patients with a KRAS mutation, or an ALK rearrangement. c-MYC gain (but not chromosome 8 gain or c-MYC amplification) was an independent poor-prognostic factor in the full cohort of lung adenocarcinoma (P=0.022, hazard ratio (HR)=1.71, 95% confidence interval (CI), 1.08-2.69 for DFS; P=0.032, HR=2.04, 95% CI, 1.06-3.91 for OS), as well as in stage I subgroup (P=0.023, HR=4.70, 95% CI, 1.24-17.78 for DFS; P=0.031, HR=4.65, 95% CI, 1.15-18.81 for OS), and in EGFR-mutant subgroup (P=0.022; HR=2.14; 95% CI, 1.11-4.10 for DFS).

CONCLUSIONS

c-MYC gain (but not chromosome 8 gain or c-MYC amplification) was an independent poor-prognostic factor for DFS and OS in lung adenocarcinomas, both in full cohort and stage I cancer, and possibly for DFS in EGFR-mutant adenocarcinomas. Additional studies are required to determine if patients with lung adenocarcinoma with c-MYC gain are candidates for additional first-line treatment to mitigate their increased risk for disease progression and death.

Crystallization mechanisms of phase change (GeSbSn)(100-x)Co(x) optical recording films

In this study, the (GeSbSn)(100-x0Co(x) films (x = 0-13.3) were deposited on natural oxidized silicon wafer and glass substrate by dc magnetron co-sputtering of GeSbSn and Co targets. The ZnS-SiO2 films were used as protective layers. The thicknesses of the (GeSbSn)(100-x)Co(x) films and protective layer were 100 nm and 30 nm, respectively. We investigated the effects of Co addition on the thermal property, crystallization kinetics, and crystallization mechanism of the GeSbSn recording film. The crystallization temperatures of (GeSbSn)(100-x)Co(x) films were decreased with Co content. It was found that the activation energy of the (GeSbSn)(100-x)Co(x) films will decrease from 1.53 eV to 0.55 eV as Co content increased from 0 at.% to 13.3 at.%.

Concurrent intracardiac metastasis in a patient with intestinal perforation

The administration of anaesthesia to subjects with intracardiac lesions poses the potential for cardiac complications. Cardiac metastases should be identified in susceptible cases and transthoracic echocardiography performed to elucidate the nature of the cardiac lesions. We describe a case of an intracardiac metastasis in a 65-year-old subject with a small bowel tumour leading to intestinal perforation and presenting for surgical treatment. Oncological assessment of the situation, in conjunction with the anaesthetic risks, led to abandonment of surgery and palliative treatment.

Narrow-band imaging with magnifying endoscopy for the screening of esophageal cancer in patients with primary head and neck cancers

BACKGROUND AND STUDY AIM

Although narrow-band imaging (NBI) in endoscopy can improve detection of early-stage esophageal malignancies in patients with head and neck cancers, false-positive results may be obtained in areas with nonspecific inflammatory changes. This study evaluated the feasibility of primary screening with NBI and magnification for the presence of esophageal malignancies in these cancer patients.

PATIENTS AND METHODS

Sixty-nine patients with documented head and neck cancers were enrolled from April 2008 to January 2009. All patients underwent a meticulous endoscopic examination of the esophagus using a conventional white-light system followed by re-examination using the NBI system and final confirmation with NBI plus magnification.

RESULTS

Twenty-one patients (30.4 %) were confirmed to have esophageal neoplasia. Among these 21, 16 (76.2 %) had synchronous lesions, 9 (42.9 %) were asymptomatic, and 10 (47.6 %) had early-stage neoplasia. The incidence of multiple esophageal neoplasia was 57.1 %. NBI was more effective than conventional endoscopy in detecting neoplastic lesions (35 lesions in 21 patients vs. 22 lesions in 18 patients) and was particularly effective in patients with dysplasia (13 lesions in 9 patients vs. 3 lesions in 3 patients). The sensitivity and accuracy of detection were 62.9 % and 64.4 % for conventional endoscopy, 100 % and 86.7 % for NBI alone, and 100 % and 95.6 % for NBI with high magnification, respectively.

CONCLUSIONS

Compared with current approaches, NBI followed by high magnification significantly increases the accuracy of detection of esophageal neoplasia in patients with head and neck cancers. The result warrants conducting prospective randomized controlled study to confirm its efficacy.

M(1)-like muscarinic acetylcholine receptors regulate fast-spiking interneuron excitability in rat dentate gyrus

Cholinergic transmission through muscarinic acetylcholine receptors (mAChRs) plays a key role in cortical oscillations. Although fast-spiking (FS), parvalbumin-expressing basket cells (BCs) are proposed to be the cellular substrates of gamma oscillations, previous studies reported that FS nonpyramidal cells in neocortical areas are unresponsive to cholinergic modulation. Dentate gyrus (DG) is an independent gamma oscillator in the hippocampal formation. However, in contrast to other cortical regions, the direct impact of mAChR activation on FS BC excitability in this area has not been investigated. Here, we show that bath-applied muscarine or carbachol, two mAChR agonists, depolarize DG BCs in the acute brain slices, leading to action potential firing in the theta-gamma bands in the presence of blockers of ionotropic glutamate and gamma-aminobutyric acid type A receptors at physiological temperatures. The depolarizing action persists in the presence of tetrodotoxin, a voltage-gated Na(+) channel blocker. In voltage-clamp recordings, muscarine markedly reduces background K(+) currents. These effects are mimicked by oxotremorine methiodide, an mAChR-specific agonist, and largely reversed by atropine, a non-selective mAChR antagonist, or pirenzepine, an M(1) receptor antagonist, but not by gallamine, an M(2/4) receptor antagonist. Interestingly, in contrast to M(1)-receptor-mediated depolarization, M(2) receptor activation by the specific agonist arecaidine but-2-ynyl ester tosylate down-regulates GABA release at BC axons-the effect is occluded by gallamine, an M(2) receptor antagonist. Overall, muscarinic activation results in a net increase in phasic inhibitory output to the target cells. Thus, cholinergic activation through M(1)-like receptor enhances BC activity and promotes the generation of nested theta and gamma rhythms, thereby enhancing hippocampal function and associated performance.

O17. The development of 'time release' nail enamels

In our recent studies on the effects of plasticizers on nail enamel films, we developed a high interest in a phenomenon that we named as 'internal flow'[1]. During the film forming process there is an area that develops beneath the film surface where the film components remain dynamic and mobile. The time frame during which the film maintains this status is directly related to the balance of the resins, plasticizers, polymers and solvents utilized. We found that the longer this 'internal flow' persists, the better the nail enamel wears. At Tevco, we have been able to control the rate at which the solvents and plasticizers flash off the substrate during the film forming process by regulating the interactions and the levels of film constituents. This 'time release' action is the foundation of our study. This study shows that the alkyl adipates are an integral component in controlling the film's internal flow through time release. As plasticizers, these materials, when in proper balance with other components, can create a film surface that is crack-and scuff-resistant. Finally, the substrate in this study is the human nail. The film we developed has to adhere and provide consistent performance over a wide range of temperatures, oil content and the surface abrasion of human nails. We have found that by utilizing adhesion promoters in conjunction with our optimized internal flow time release formula, our film meets all required criteria and generally outperforms conventional quick dry films. In conclusion, we have been able to optimize the film characteristics of conventional quick dry nail enamels. By controlling the internal flow of the film, we can enhance the performance criteria generally expected by consumers in nail enamels.

Role of the virulence plasmid pR99 and the metalloprotease Vvp in resistance of Vibrio vulnificus serovar E to eel innate immunity

Vibrio vulnificus biotype 2 serovar E (VSE) is a bacterial pathogen that produces a haemorrhagic septicaemia called vibriosis in eels. Its ability to grow in blood is conferred by a recently described virulence plasmid [Lee CT, Amaro C, Wu KM, Valiente E, Chang YF, Tsai SF, et al. A common virulence plasmid in biotype 2 Vibrio vulnificus and its dissemination aided by a conjugal plasmid. Journal of Bacteriology, submitted for publication.]. In this study, we analyzed the role of this plasmid together with the role played by the metalloprotease (Vvp) in the interaction between bacteria and eel innate immunity. To this end, we compared and statistically analyzed the differences in resistance to serum and mucus factors (complement, selected antimicrobial peptides, transferrin and lysozyme) and also to phagocytosis/opsonophagocytosis between one VSE strain and its derivatives: a plasmid-cured strain and a vvp-deficient mutant. The wild-type and the metalloprotease-deficient strains were resistant to both the bactericidal action of fresh serum and the phagocytosis and opsonophagocytosis by eel phagocytes, confirming that Vvp is not involved in resistance to eel innate immunity. In contrast, the cured strain was sensitive to both the bactericidal action of eel serum activated by the alternative pathway and phagocytosis/opsonophagocytosis. Since no plasmid-encoded ORF, with homology to known genes, is related to the resistance to innate immunity [Lee CT, Amaro C, Wu KM, Valiente E, Chang YF, Tsai SF, et al. A common virulence plasmid in biotype 2 Vibrio vulnificus and its dissemination aided by a conjugal plasmid. Journal of Bacteriology, submitted for publication.], this function could be codified by one or more new genes. Further studies are underway to characterize the plasmid-encoded system responsible for V. vulnificus resistance to the innate immune system of eels.

An immortalized rat ventral mesencephalic cell line, RTC4, is protective in a rodent model of stroke

One therapeutic approach to stroke is the transplantation of cells capable of trophic support, reinnervation, and/or regeneration. Previously, we have described the use of novel truncated isoforms of SV40 large T antigen to generate unique cell lines from several primary rodent tissue types. Here we describe the generation of two cell lines, RTC3 and RTC4, derived from primary mesencephalic tissue using a fragment of mutant T antigen, T155c (cDNA) expressed from the RSV promoter. Both lines expressed the glial markers vimentin and S100beta, but not the neuronal markers NeuN, MAP2, or beta-III-tubulin. A screen for secreted trophic factors revealed substantially elevated levels of platelet-derived growth factor (PDGF) in RTC4, but not RTC3 cells. When transplanted into rat cortex, RTC4 cells survived for at least 22 days and expressed PDGF. Because PDGF has been reported to reduce ischemic injury, we examined the protective functions of RTC4 cells in an animal model of stroke. RTC4 or RTC3 cells, or vehicle, were injected into rat cortex 15-20 min prior to a 60-min middle cerebral artery ligation. Forty-eight hours later, animals were sacrificed and the stroke volume was assessed by triphenyl-tetrazolium chloride (TTC) staining. Compared to vehicle or RTC3 cells, transplanted RTC4 cells significantly reduced stroke volume. Overall, we generated a cell line with glial properties that produces PDGF and reduces ischemic injury in a rat model of stroke.

Determinants of diagnostic bronchial washing in peripheral lung cancers

OBJECTIVE

To establish clinical determinants affecting the diagnostic yield of bronchial washing.

SETTING

We performed bronchial washing in 241 consecutive patients with bronchoscopically invisible lung tumours. Of these, 150 patients known to have lung cancer were enrolled for the final analysis.

DESIGN

A multi-centre study.

RESULTS

Bronchial washing provided a diagnosis of lung cancer in 30 of the 150 patients (20%). Tumour size > or = 3 cm (P = 0.005), the location of the tumour within 8 cm of the carina (P = 0.003), and exposed type bronchus sign of tumour (P < 0.001) were factors affecting diagnostic bronchial washing for bronchoscopically invisible lung cancers. However, multivariate logistic regression revealed that exposed type bronchus sign was the sole determinant (OR 19.22, 95% CI 4.23-87.46, P < 0.001).

CONCLUSION

Bronchial washing is a useful procedure for the diagnosis of bronchoscopically invisible lung cancers. As the tumour-bronchus relationship is the most important determinant of a diagnostic yield, the routine use of bronchial washing should be considered for tumours with exposed type bronchus sign.

Lack of association between COPD and transforming growth factor-beta1 (TGFB1) genetic polymorphisms in Koreans

OBJECTIVE

Many genetic variations have been suggested as genetic risk factors for the development of chronic obstructive pulmonary disease (COPD), including single nucleotide polymorphisms in the transforming growth factor-beta1 (TGFB1) gene. We attempted to elucidate the association between TGFB1 genetic polymorphisms and COPD among Koreans.

DESIGN

The genotypes of 102 male patients with COPD and 159 volunteers with similar distributions of age, sex and smoking intensity, as well as normal pulmonary function, were determined for three previously associated TGFB1 single nucleotide polymorphisms (SNPs), -10807G/A (rs2241712) and -509T/C (rs1800469), located in or near the promoter, and 29T/C (rs1982073), located in exon 1 of the TGFB1 gene.

RESULTS

No significant associations between COPD and the three TGFB1 SNPs could be identified. In addition, the haplotypes composed of three TGFB1 SNPs were not associated with the presence of COPD.

CONCLUSION

These results differ from previous reports involving Caucasians, and might reflect racial differences in the pathogenesis of COPD.

Recombinant human erythropoietin independence in chronic hemodialysis patients: clinical features, iron homeostasis and erythropoiesis

AIMS

Recombinant human erythropoietin (r-HuEPO) is widely used to correct renal anemia in uremic patients. Interestingly, some chronic hemodialysis (HD) patients can maintain high hemoglobin level without the need of r-HuEPO. The aim of this study is to investigate clinical features, iron metabolism and erythropoiesis of these r-HuEPO-independent HD patients.

METHODS

r-HuEPO independence was defined in dialysis patients as hemoglobin greater than 12 g/dl and no use of r-HuEPO for at least 6 months. An age- and sex-matched group was selected for comparison. Their underlying diseases, duration of hemodialysis therapy, efficacy of dialysis (Kt/V), normalized protein catabolic rate (nPCR) and body mass index (BMI) were recorded. Laboratory data including: hemoglobin, albumin, high sensitivity C-reactive protein, serum iron, total iron binding capacity, transferrin saturation, ferritin, intact parathyroid hormone, soluble transferrin receptor (sTfR), serum EPO, cortisol, testosterone, aluminum and leptin levels were measured. Renal sonography was also performed in each patient to evaluate renal cyst formation.

RESULTS

About 2.3% of all HD patients (21/888; M : F = 18 : 3) were r-HuEPO-independent. These patients had significantly longer HD duration and higher serum EPO and sTfR levels, and lower transferrin saturation rate than dependent groups. Correlation analysis revealed that hemoglobin level strongly correlated with HD duration, serum sTfR and EPO levels. Levels of sTfR were positively related with serum EPO levels and BMI. Multivariate regression analysis showed that level of sTfR was the only independent factor related to r-HuEPO independence.

CONCLUSION

R-HuEPO independence is rare among chronic hemodialysis patients. Factors contributing to this dependence are complex and multiple. Level of serum sTfR parallels erythropoiesis and is the most significant factor associated with r-HuEPO independence in chronic HD patients.

Hypercalcaemia and haemophagocytic syndrome: rare concurrent presentations of disseminated tuberculosis in a dialysis patient

Tuberculosis remains an important cause of infection in chronic haemodialysis patients. Frequent extrapulmonary involvement, non-specific presentation and limited diagnostic tools usually make early diagnosis difficult. Herein, we report on an 83-year-old female patient who had been on regular heamodialysis therapy for 15 years, who presented with asymptomatic hypercalcaemia and pancytopenia. Haemophagocytic syndrome was documented during the admission period. Mycobacterium tuberculosis was cultured from bone marrow 1 month after her demise. This case report highlights the non-specific manifestations of extrapulmonary tuberculosis in dialysis patients and the limited value of conventional diagnostic methods. We would like to recommend aggressive intervention and early tissue aspiration from possible infectious sites when tuberculosis cannot be completely ruled out. Disseminated tuberculosis should be considered as an indication of hypercalcaemia where haemophagocytic syndrome occurs simultaneously.

Response of pulmonary tuberculomas to anti-tuberculous treatment

Pulmonary tuberculomas are well-circumscribed masses caused by Mycobacterium tuberculosis. However, the response of tuberculomas to anti-tuberculous (TB) treatment has not been well defined as yet. The response of pulmonary tuberculomas to anti-TB treatment was retrospectively reviewed in 45 patients diagnosed between January 1997 and December 2001. The areas of pulmonary tuberculomas were estimated by calculating products of the longest and their perpendicular short diameters on chest radiographs. The response to anti-TB treatment was categorised as "decreased" (> 25% reduction in area versus its initial area), "increased" (> 251% increase) and "no change" (the remainder). The mean of treatment duration was 11.5 +/- 3.6 months. Three months after treatment, 18 patients (40.0%) were categorised as decreased, 25 (55.6%) as no change and two (4.4%) as increased. Twelve months after treatment, out of 42 patients available for chest radiographs, 32 patients (76.2%) were categorised as decreased, nine (21.4%) as no change and one patient (2.4%) as increased. At the last follow-up (mean follow-up 27.0 +/- 10.2 months), 37 patients (82.2%) were categorised as decreased. The majority of pulmonary tuberculomas were decreased by anti-tuberculosis treatment during and even after treatment, although a transient enlargement during the early period of treatment was observed infrequently.

Isolated fatal renal mucormycosis in a patient with chronic obstructive pulmonary disease and tuberculosis

Renal mucormyosis is a rare entity and normally diagnosed at postmortem. Isolated cases diagnosed antemortem are even rarer and only a few cases have been reported. The disease is associated with a high mortality rate, especially in patients with underlying disease. Clinical presentation is non-specific and includes flank pain, fever and pyuria with or without haematuria. Identifying fungal hyphae microscopically is essential for diagnosis. We present a rare isolated fatal case of renal mucormycosis in a 77-year-old man with chronic obstructive pulmonary disease (COPD) and old tuberculosis (TB) who had been diagnosed after a right nephrectomy. We believe early diagnosis and appropriate treatment for fungal infection, together with the predisposing underlying disease, is crucial for survival.

Tuberculous peritonitis in uremic patients

AIMS

To identify clinical features and treatment response of tuberculous peritonitis (TBP) in a uremic population, a retrospective case-control study was performed.

MATERIALS AND METHODS

Thirteen uremic patients with TBP (Group I: 62.7 +/- 6.8 years, male 54%) collected between January 1986 and January 2002 were compared with another two age- and sex-matched controls: 19 non-azotemic patients with TBP (Group II: 62.9 +/- 7.3 years, male 47%) and 30 uremic patients without TBP (Group III: 61.1 +/- 8.7 years, male 47%). Clinical information and data of ascites and blood examinations were evaluated.

RESULTS

Significant differences between Groups I and II were found in comorbidity, hypertension, anorexia, percentages of neutrophil and lymphocyte from blood and ascites, and serum calcium (sCa), phosphorus and albumin-adjusted calcium (sAACa). However, no significant differences in duration of symptoms, coexistent pulmonary tuberculosis (p = 0.061), duration or complications of therapy and mortality (p = 0.13) were detected. Significant differences between Groups I and III were found in peripheral white cell counts and percentages of neutrophil and lymphocyte as well as in serum creatinine (sCr), albumin, sCa, sAACa and intact parathyroid hormone (iPTH).

CONCLUSIONS

Non-specific symptoms make the diagnosis of TBP in a uremic population difficult. However, neutrophil predominance in blood and ascites, hypoalbuminemia, relatively lower sCr and hypercalcemia with suppressed serum iPTH were found to be characteristic. In TBP uremic patients, therapy complications were not common and there was a tendency for higher mortality, largely due to septic shock.

Outcome of pregnancy in Asian women with systemic lupus erythematosus: experience of a single perinatal centre in Singapore

OBJECTIVE

To study maternal and fetal outcomes in women with systemic lupus erythematosus (SLE).

MATERIALS AND METHODS

Retrospective study of 27 pregnancies in 18 women with SLE in a single centre.

RESULTS

The mean age was 30 years and most patients were nulliparous. Twenty-six of 27 pregnancies were in disease remission at the time of booking. Renal impairment was present in 7 pregnancies (6 women), of whom 2 were in end-stage renal disease on dialysis. Gestational diabetes developed in 4 pregnancies. There were 6 cases of pre-existing hypertension and 5 with superimposed pre-eclampsia. One woman developed intrapartum eclampsia. Two women had secondary antiphospholipid syndrome (APS) and suffered late fetal losses; in addition, they also developed SLE flares in the form of autoimmune haemolytic anaemia in the postpartum period. There was no maternal mortality. There was one termination of pregnancy for severe renal disease. The median gestational age at delivery was 38 weeks (range, 24 to 40 weeks) and the mean birth weight was 3047 g; the median Apgar scores were 8 and 9 at 1 and 5 minutes of life, respectively. There were 5 cases of intrauterine growth restriction (IUGR), 4 of which occurred in women with renal impairment. There were no cases of congenital heart block or neonatal lupus. There was a late fetal loss at 24 weeks in a woman with secondary APS. There were 2 preterm deliveries (7.4%) due to intervention for IUGR.

CONCLUSION

Good pregnancy outcomes can be expected in women with SLE in remission. Pre-pregnancy counselling is crucial to achieve this. All pregnancies should still be considered high risk and be managed jointly between the obstetricians, the perinatologists and the physicians. In particular, those with renal impairment are at increased risk of IUGR, superimposed pre-eclampsia and preterm births. Co-existing APS augurs a poorer prognosis for pregnancy outcome, and may present atypically as autoimmune haemolytic anaemia in the postpartum period.

Perioperative ulnar neuropathy in orthopaedics: association with tilting the patient

The incidence and causes of perioperative ulnar neuropathy in a prospective series of 203 consecutive patients were examined. Three percent of patients had ulnar neuropathy develop in the entire prospective series. The incidence was 6% in patients having total hip arthroplasty. There was a highly significant association between a tilted body position on the operating table and development of ulnar neuropathy on the contralateral side. This position rotates the arm internally and places the ulnar nerve at risk for direct compression.

Aortobronchial fistula presenting as recurrent hemoptysis and successfully treated with an endovascular stent graft

Aortobronchial fistula (ABF) (aortopulmonary fistula) may cause a massive fatal hemoptysis. We have recently seen a patient with ABF presenting with recurrent, massive hemoptysis. She was successfully treated with an endovascular stent graft. The endovascular stent graft may provide an alternative treatment of in patients considered to be poor surgical candidates.

Implications of sonographic identification of duplex kidney in adults

BACKGROUND

Duplication of the renal pelvis and ureter constitutes the most common anomalies of the upper urinary tract. Most patients are asymptomatic and don't need treatment. However, the associated anomaly and acquired renal disease may cause morbidity and mortality. The aim of this study was to investigate the prevalence of duplex kidney in sonographic examinations and the predictive capability of this method. An analysis of patients with urography-confirmed duplication anomaly was also performed.

METHODS

During a period of 9 year (from 1988 to 1996), sonographic examination records of 19,287 patients were reviewed. Patients with a diagnosis of duplex kidney were enrolled. Their clinical characteristics and radiological images were recorded and evaluated.

RESULTS

One hundred and sixty-three patients were found by sonography to have duplex kidney, for an prevalence of 0.85%. Urography studies were done on 64 (39.2%) patients, and 42 patients were proven to have duplex kidney. The positive predictive rate of sonography was 65.6%. Eighty percent of patients with duplex kidney had associated ureteral duplication. No associated anomalies were found. Four patients had urolithiasis, and 3 patients had recurrent urinary tract infection. One patient had coexisting uroepithelial malignancy, and 1 patient had refractory gross hematuria.

CONCLUSIONS

Duplex kidney is an uncommon finding during adult sonographic examinations. The sensitivity and specificity of sonography in identifying this anomaly are controversial. An experienced hand with good knowledge of the anomaly and its sonographic signs is helpful in more accurately diagnosing this anomaly.

Catalysis in supercritical CO2 using dendrimer-encapsulated palladium nanoparticles

Dendrimer-encapsulated nanoparticles are shown to be versatile catalysts for both the hydrogenation of styrene and Heck heterocoupling of iodobenzene and methacrylate in supercritical CO2 (scCO2).

Neglected bilateral femoral neck fractures in a patient with end-stage renal disease before chronic dialysis

Bilateral femoral neck fractures are rarely reported in patients with end-stage renal disease before chronic dialysis. We report on a 39-year-old woman with neglected bilateral femoral neck fractures, who presented with severe uremic complications prior to chronic dialysis. Three years before admission, she had injured herself in a trivial slip with subsequent bilateral hip pain. She had progressively waddled since then. Pelvic X-ray taken after admission revealed bilateral femoral neck fractures. Bilateral hip hemiarthroplasties were subsequently performed. Displaced femoral neck fractures were found intraoperatively. Pathologic findings and results of examinations supported the coexistence of osteoporosis and high turnover renal osteodystrophy, rendering this woman at high risk of bilateral femoral neck fractures. Therefore, preventing a simple fall or trivial accident and treating renal osteodystrophy and osteoporosis are paramount in patients with chronic renal failure even before the start of dialysis therapy. We also emphasize the need to seek any possible underlying metabolic bone disease once a patient presents with unusual fractures.

Phase II Trial of Vinorelbine and Cisplatin Chemotherapy in Advanced Non-Small Cell Lung Cancer

PURPOSE

Platinum-based chemotherapy has conferred a modest but significant survival benefit and the introduction of newer drugs has led to achieve higher response rate in patients with advanced non-small cell lung cancer (NSCLC). We performed a phase II trial in order to evaluate the efficacy and toxicity of combination chemotherapy with vinorelbine (Navelbine) and cisplatin in advanced NSCLC.

MATERIALS AND METHODS

Patients with previously untreated, unresectable stage IIIB or IV NSCLC with measurable lesion (s) were eligible for entry into the study. NP chemotherapy consisted of intravenous vinorelbine 25 mg/m2, on day 1 and 8, and intravenous cisplatin 80 mg/m2 on day 1; this cycle was repeated every three weeks.

RESULTS

A total of 33 patients were enrolled in the study between July 1999 and Feb 2000. Of the 30 patients deemed eligible for analysis, thirteen patients achieved a partial response and thirteen showed a stable disease. The overall response rate was 43.3%. The median duration of response was 5.7 months (95% CI: 2.8~8.5 months). The median time to progression was 7.6 months (95% CI: 5.5~9.7 months) and the overall median survival time was 15.1 months (95% CI: 9.8~20.4 months) in the intent-to-treat analysis. Chemotherapy-related grade 3 or 4 toxicities were anemia in 1.5%, leukopenia in 4.5%, nausea/vomiting in 2.3%, alopecia in 13.3%, and neurotoxicity in 3.3%.

CONCLUSION

The combination of vinorelbine and cisplatin chemotherapy seems to be active and fairly tolerable in patients with advanced NSCLC.

Effects of turn residues in directing the formation of the beta-sheet and in the stability of the beta-sheet

The designed peptide (denoted 20-mer, sequence VFITS(D)PGKTYTEV(D)PGOKILQ) has been shown to form a three-strand antiparallel beta-sheet. It is generally believed that the (D)Pro-Gly segment has the propensity to adopt a type II' beta-turn, thereby promoting the formation of this beta-sheet. Here, we replaced (D)Pro-Gly with Asp-Gly, which should favor a type I' turn, to examine the influence of different type of turns on the stability of the beta-sheet. Contrary to our expectation, the mutant peptide, denoted P6D, forms a five-residue type I turn plus a beta-bulge between the first two strands due to a one amino-acid frameshift in the hydrogen bonding network and side-chain inversion of the first beta-strand. In contrast, the same kind of substitution at (D)Pro-14 in the double mutant, denoted P6DP14D, does not yield the same effect. These observations suggest that the SDGK sequence disfavors the type I' conformation while the VDGO sequence favors a type I' turn, and that the frameshift in the first strand provides a way for the peptide to accommodate a disfavored turn sequence by protruding a bulge in the formation of the beta-hairpin. Thus, different types of turns can affect the stability of a beta-structure.

An adenovirus expressing mutant p27 showed more potent antitumor effects than adenovirus-p27 wild type

The main inhibitory action of p27, a cyclin-dependent kinase inhibitor (CDKI), arises from its binding with the cyclin E/cyclin-dependent kinase 2 (Cdk2) complex that results in G(1)-S arrest. Degradation of p27 is mediated by phosphorylation of Thr-187 of p27, which follows ubiquitination. In this study, we generated two adenoviruses expressing wild-type p27 (ad-p27wt) and mutant p27 (ad-p27mt), with mutation of Thr-187/Pro-188 (ACGCCC) to Met-187/Ile-188 (ATGATC), which was produced with the belief that mutant p27 would bind cyclin E/CDK2 more stably and show more potent antitumor effects. Ad-p27wt and ad-p27mt expressed p27 proteins that were indistinguishable by anti-p27 antibody. A pulse chase experiment showed that p27mt was more resistant to degradation than p27wt. In human lung cancer cell lines, ad-p27mt showed stronger growth inhibition than ad-p27wt. Both types of ad-p27 induced G(1)-S arrest and apoptosis; however, ad-p27mt induced stronger G(1)-S arrest and apoptosis. Intratumoral injection of ad-p27mt induced partial regression of established tumors and inhibited the growth of human lung cancer xenografts more strongly than ad-p27wt. From these results, we conclude that ad-p27mt has the potential to become a novel and powerful gene therapy tool.

Radiographic versus pathologic size of renal tumors: implications for partial nephrectomy

OBJECTIVES

To compare the radiographic size with the pathologic size of renal tumors to determine whether these two measurements vary significantly and to evaluate whether any differences in tumor size could have an impact on the decisions regarding partial nephrectomy.

METHODS

In 87 renal tumors excised by partial nephrectomy, the maximum transaxial tumor size on computed tomography (CT) was compared with its corresponding pathologic transverse size. Tumors were locally excised after vascular occlusion and hypothermia. The average size of the tumors selected for partial nephrectomy by preoperative CT scan was 3.4 cm (range 1.9 to 9.3). The difference between the CT size and pathologic size was correlated with the histologic type of the renal tumors.

RESULTS

Of the 87 tumors, 52 (60%) were classified as clear cell carcinoma and 35 (40%) as other histologic types (papillary, chromophobe, oncocytoma, and angiomyolipoma). Clear cell carcinomas decreased an average of 0.97 cm versus 0.39 cm for the other tumor types. Of 62 tumors greater than 3 cm on CT, 43 averaged 0.87 cm smaller at pathologic evaluation (36 clear cell and 7 other types) and 19 showed no significant (less than 0.5 cm) decrease in size (2 clear cell and 17 other histologic types). Of 30 tumors greater than 4 cm on CT, 22 clear cell carcinomas shrank more than 1 cm and 8 tumors displaying other histologic features showed no decrease in size.

CONCLUSIONS

For renal tumors measuring greater than 4 cm, a decrease in tumor size may help facilitate partial nephrectomy, especially for clear cell carcinomas that do not extensively involve major vascular structures or the collecting system.

Intrahepatic genetic inoculation of hepatitis C virus RNA confers cross-protective immunity

Naturally occurring hepatitis C virus (HCV) infection has long been thought to induce a weak immunity which is insufficient to protect an individual from subsequent infections and has cast doubt on the ability to develop effective vaccines. A series of intrahepatic genetic inoculations (IHGI) with type 1a HCV RNA were performed in a chimpanzee to determine whether a form of genetic immunization might stimulate protective immunity. We demonstrate that the chimpanzee not only developed protective immunity to the homologous type 1a RNA after rechallenge by IHGI but was also protected from chronic HCV infection after sequential rechallenge with 100 50% chimpanzee infectious doses of a heterologous type 1a (H77) and 1b (HC-J4) whole-virus inoculum. These results offer encouragement to pursue the development of HCV vaccines.

Physiological function of the orphans GCNF and COUP-TF

Orphan nuclear receptors are members of the nuclear receptor superfamily of ligand-activated transcription factors for which ligands and functions have not been identified. Since the cloning of the original orphans, ligands have been identified for several orphan receptors that heterodimerize with the retinoid X receptor and are no longer classified as orphan receptors. Considering the central role that nuclear receptors play in differentiation, development, metabolic regulation, homeostasis and disease, it is crucial that we understand the roles of the remaining orphans. However, the identification of ligands for those orphans that form homodimers has proven more difficult. Thus, to gain greater insight into the functions of orphan receptors, gene targeting has been used to knock out these factors and study mouse development in their absence. Here we will review the progress made in understanding the roles of the orphans GCNF and the COUP-TFs with the use of gene knockouts.

The effect of total sleep deprivation on cognitive functions in normal adult male subjects

This study was conducted to evaluate the effect of acute sleep deprivation on cognitive functions. A total of 18 healthy right handed males were deprived of sleep for 24 hours. Luria-Nebraska Neuropsychological Battery and calculation & digit-span subtest of K-WAIS were administered before and after sleep deprivation in order to examine the changes of cognitive functions. There were no differences in freedom from distractibility, tacile function, visual function, reading, writing, arithmetic and intellectual process function. However, the cognitive functions such as motor, rhythm, receptive & expressive speech, memory and complex verbal arithmetic function were decreased after sleep deprivation. All of these functions are known to be related to the right anterior hemisphere. For localization scales, the scores of right frontal and right temporal dysfunction scale were increased after sleep deprivation. These results indicate that sleep deprivation has a negative effect on cognitive functions, especially those associated with right anterior hemisphere or subcortical areas.

Characterization of action potential waveform-evoked L-type calcium currents in pituitary GH3 cells

The response of the L-type Ca2+ current (ICa,L) in pituitary GH3 cells to variations in the action potential (AP) waveform was examined using the whole-cell configuration of the patch-clamp technique. ICa,L evoked during an AP waveform exhibited an early and a late component. The early component occurred on the rising phase of the AP; the late component coincided with the falling phase. Prolonging the falling phase of the AP increased the Ca2+ charge carried by ICa,L, although the amplitude of the late ICa,L was reduced. Prolonging the peak voltage of the AP waveform, however, increased the amplitude of the late component. ICa,L inactivated during a train of AP waveforms. When Ba2+ was used as the charge carrier, current inactivation during a train of APs decreased. Likewise, ICa,L evoked by the AP templates with irregular bursting pattern was inactivated. When the repetitive firing of APs with depolarizing potentials was replayed to cells, Ca2+ entry was not only spread over the entire AP, but also occurred during the interspike voltage trajectory. After application of thyrotropin releasing hormone (TRH; 10 microM), ICa,L in response to rectangular pulses was increased and the current/voltage relation shifted slightly to more negative values. TRH (10 microM), thapsigargin (10 microM) or cyclopiazonic acid (30 microM) enhanced the late component of the AP-evoked ICa,L. TRH also attenuated the inactivation of ICa,L during a train of APs. These results indicate that in pituitary GH3 cells, the time course and kinetics of ICa,L during the AP waveforms is distinct from that evoked by rectangular voltage clamp. Changes in the shape and firing pattern of APs in GH3 cells can modulate Ca2+ influx through L-type Ca2+ channels. Ca2+ release from internal stores may affect the magnitude of AP-evoked ICa,L in these cells.

Preservation of ancient and fertile lithospheric mantle beneath the southwestern United States

Stable continental regions, free from tectonic activity, are generally found only within ancient cratons-the centres of continents which formed in the Archaean era, 4.0-2.5 Gyr ago. But in the Cordilleran mountain belt of western North America some younger (middle Proterozoic) regions have remained stable, whereas some older (late Archaean) regions have been tectonically disturbed, suggesting that age alone does not determine lithospheric strength and crustal stability. Here we report rhenium-osmium isotope and mineral compositions of peridotite xenoliths from two regions of the Cordilleran mountain belt. We found that the younger, undeformed Colorado plateau is underlain by lithospheric mantle that is 'depleted' (deficient in minerals extracted by partial melting of the rock), whereas the older (Archaean), yet deformed, southern Basin and Range province is underlain by 'fertile' lithospheric mantle (not depleted by melt extraction). We suggest that the apparent relationship between composition and lithospheric strength, inferred from different degrees of crustal deformation, occurs because depleted mantle is intrinsically less dense than fertile mantle (due to iron having been lost when melt was extracted from the rock). This allows the depleted mantle to form a thicker thermal boundary layer between the deep convecting mantle and the crust, thus reducing tectonic activity at the surface. The inference that not all Archaean crust developed a strong and thick thermal boundary layer leads to the possibility that such ancient crust may have been overlooked because of its intensive reworking or lost from the geological record owing to preferential recycling.

Non-local Concepts and Models in Biology

In this paper, we consider local and non-local spatially explicit mathematical models for biological phenomena. We show that, when rate differences between fast and slow local dynamics are great enough, non-local models are adequate simplifications of local models. Non-local models thus avoid describing fast processes in mechanistic detail, instead describing the effects of fast processes on slower ones. As a consequence, non-local models are helpful to biologists because they describe biological systems on scales that are convenient to observation, data collection, and insight. We illustrate these arguments by comparing local and non-local models for the aggregation of hypothetical organisms, and we support theoretical ideas with concrete examples from cell biology and animal behavior.

Serotyping and antimicrobial susceptibility of group B Streptococcus over an eight-year period in southern Taiwan

The increase in penicillin resistance among pneumococci and viridans streptococci and the development of serotype-specific conjugate vaccine have increased the need for knowledge of the antimicrobial susceptibility and the capsular serotypes of group B streptococci. Over an 8-year period, 351 group B streptococcal isolates from southern Taiwan were tested for antimicrobial susceptibility and serotype determination. Eighty-seven percent of the isolates were typeable. Types III (28.5%) and V (27.1%) were the most common serotypes. The occurrence of type V isolates increased with age, while that of type III isolates decreased with age, showing a predominance in children less than 1 year of age. Of 118 isolates from cases of invasive infection, types Ia, Ib, II, III, IV, and V accounted for 12.7, 11.9, 0.8, 33, 1.7, and 26.3%, respectively. Using the agar dilution method, all isolates were found to be susceptible to penicillin, cefotaxime, and vancomycin, 99.4% to ofloxacin, 78.1% to chloramphenicol, 63.2% to azithromycin, 62.6% to erythromycin, 57.3% to clindamycin, and 2.8% to tetracycline. Chloramphenicol resistance was associated with type III isolates (59 of 100, 59%) and erythromycin and azithromycin resistance with type Ib isolates (25 of 33 176%], and 21 of 33 [64%], respectively). Thus, 72% of the isolates from invasive infections were serotype III, V, or Ia, and penicillin remains the drug of choice for treatment or prophylaxis of group B streptococcal infections in southern Taiwan, despite the high prevalence of penicillin resistance among Streptococcus pneumoniae and viridans streptococci.

In vivo antitumor effect of herpes simplex virus thymidine kinase gene therapy in rat hepatocellular carcinoma: feasibility of adenovirus-mediated intra-arterial gene delivery

Transfer of the herpes simplex virus-thymidine kinase gene, followed by the administration of ganciclovir (HSV-tk/GCV), has been a major approach for cancer gene therapy. We investigated the antitumor effect of the HSV-tk/GCV strategy with the rat orthotopic hepatocellular carcinoma (HCC) model and the tumor-selective gene delivery by an adenovirus-mediated gene transfer through the hepatic artery. The complete antitumor effect was demonstrated, after the treatment with GCV in rat HCC established by the implantation of HSV-tk transferred rat HCC cells. The in vivo bystander effect was also observed. The marked infiltration of CD4+ and CD8+ T lymphocytes, macrophages and NK cells were found in the tumor area. After the injection of adenovirus carrying the LacZ gene into the hepatic artery, the selective expression of transgene in the tumor cell was achieved. These findings indicate that the HSV-tk/GCV strategy, using an adenoviral vector, could be a promising avenue for the treatment of hepatocellular carcinoma.

Alteration of cell growth and morphology by overexpression of transforming growth factor beta type II receptor in human lung adenocarcinoma cells

TGF-beta is a potent inhibitory regulator of cell growth, which is transduced through interaction between type I (RI) and type II (RII) receptors that form heteromeric kinase complexes. Abnormal expression of these receptors has been identified in several human epithelial cancers and has been shown to be highly associated with resistance to TGF-beta. In this study, we investigated the expression of RI and RII in 13 human non-small cell lung cancer cell lines (NSCLCs) and demonstrated decreased or loss of RII expression in five lung cancer cell lines, but not of RI. Of these cell lines, the role of RII in NCI-H358 adenocarcinoma, which lacks RII and is insensitive to TGF-beta, was investigated by transducing this cell line with a recombinant retrovirus expressing full-length TGF-beta RII. Stably transfected cells showed significant increase in RII mRNA and protein expression. These cells responded to exogenous TGF-beta1 with suppressed proliferation in a dose-dependent manner and G1 arrest accompanied by morphological change distinct from control cells. We also investigated whether overexpression of dominant-negative RII (dnRII) in NCI-H441 adenocarcinoma, which is sensitive but expresses low levels of RII, could block signaling through the receptor complex. The overexpression of this kinase-domain-truncated RII by expressing the retroviral dnRII construct led to loss of the ability to respond to TGF-beta1 and an exhibition of uncontrolled growth. These results suggest a close association between the loss of the expression of wild-type TGF-beta RII and carcinogenesis in human lung cancer cells.