Metastatic thyroid carcinoma in the presence of struma ovarii

A 27-year-old woman presented with metastatic follicular carcinoma of thyroid cell type. Assessment was complicated by recent surgery for "benign" struma ovarii. She underwent total thyroidectomy which failed to show a neoplasm, leaving the struma ovarii as the likely source of the metastasis.

A polymorphism of the human matrix gamma-carboxyglutamic acid protein promoter alters binding of an activating protein-1 complex and is associated with altered transcription and serum levels

Matrix gamma-carboxyglutamic acid protein (MGP) is a mineral-binding extracellular matrix protein synthesized by vascular smooth muscle cells (VSMCs) and chondrocytes that is thought to be a key regulator of tissue calcification. In this study, we identified four polymorphisms in the promoter region of the human MGP gene. Transfection studies showed that the G-7A and T-138C polymorphisms have an important impact on in vitro promoter activity when transiently transfected into VSMCs. We found that one of these polymorphisms (T-138C) is significantly correlated with serum MGP levels in human subjects. Promoter deletion analysis showed that this polymorphism lies in a region of the promoter critical for transcription in VSMCs. This region contains a potential activating protein-1 (AP-1) binding element located between -142 and -136. We have demonstrated that the T-138C polymorphism results in altered binding of an AP-1 complex to this region. The -138T allelic variant binds AP-1 complexes consisting primarily of c-Jun, JunB and its partners Fra-1 and Fra-2 in rat VSMC. Furthermore, the -138T variant form of the promoter was induced following phorbol 12-myristate 13-acetate treatment, while the -138C variant was refractive to phorbol 12-myristate 13-acetate treatment, confirming that AP-1 factors preferentially bind to the -138T variant. This study therefore suggests that a common polymorphism of the MGP promoter influences binding of the AP-1 complex, which may lead to altered transcription and serum levels. This could have important implications for diseases such as atherosclerosis and aortic valve stenosis, since it strongly suggests a genetic basis for regulation of tissue calcification.

Altering telomere structure allows telomerase to act in yeast lacking ATM kinases

BACKGROUND

Telomerase is a ribonucleoprotein that copies a short RNA template into telomeric DNA, maintaining eukaryotic chromosome ends and preventing replicative senescence. Telomeres differentiate chromosome ends from DNA double-stranded breaks. Nevertheless, the DNA damage-responsive ATM kinases Tel1p and Mec1p are required for normal telomere maintenance in Saccharomyces cerevisiae. We tested whether the ATM kinases are required for telomerase enzyme activity or whether it is their action on the telomere that allows telomeric DNA synthesis.

RESULTS

Cells lacking Tel1p and Mec1p had wild-type levels of telomerase activity in vitro. Furthermore, altering telomere structure in three different ways showed that telomerase can function in ATM kinase-deleted cells: tel1 mec1 cells senesced more slowly than tel1 mec1 cells that also lacked TLC1, which encodes telomerase RNA, suggesting that tel1 mec1 cells have residual telomerase function; deleting the telomere-associated proteins Rif1p and Rif2p in tel1 mec1 cells prevented senescence; we isolated a point mutation in the telomerase RNA template domain (tlc1-476A) that altered telomeric DNA sequences, causing uncontrolled telomeric DNA elongation and increasing single strandedness. In tel1 mec1 cells, tlc1-476A telomerase was also capable of uncontrolled synthesis, but only after telomeres had shortened for >30 generations.

CONCLUSION

Our results show that, without Tel1p and Mec1p, telomerase is still active and can act in vivo when the telomere structure is disrupted by various means. Hence, a primary function of the ATM-family kinases in telomere maintenance is to act on the substrate of telomerase, the telomere, rather than to activate the enzymatic activity of telomerase.

Simian virus 40 Vp1 DNA-binding domain is functionally separable from the overlapping nuclear localization signal and is required for effective virion formation and full viability

A DNA-binding domain (DBD) was identified on simian virus 40 (SV40) major capsid protein Vp1, and the domain's function in the SV40 life cycle was examined. The DBD was mapped by assaying various recombinant Vp1 proteins for DNA binding in vitro. The carboxy-terminal 58-residue truncated Vp1DeltaC58 pentamer bound DNA with a K(d) of 1.8 x 10(-9) M in terms of the protein pentamer, while full-length Vp1 and carboxy-terminal-17-truncated Vp1DeltaC17 had comparable apparent K(d)s of 5.3 x 10(-9) to 7.3 x 10(-9) M in terms of the protein monomers. Previously identified on Vp1 was a nuclear localization signal (NLS) consisting of two N-terminal basic clusters, NLS1 (4-KRK-6) and NLS2 (15-KKPK-18). Vp1DeltaC58 pentamers harboring multiple-point mutations in NLS1 (NLSm1), NLS2 (NLSm2), or both basic clusters (NLSm1. 2) had progressively decreased DNA-binding activity, down to 0.7% of the Vp1DeltaC58 level for NLSm1. 2 Vp1. These data, along with those of N-terminally truncated proteins, placed the DBD in overlap with the bipartite NLS. The role of the Vp1 DBD during infection was investigated by taking advantage of NLS phenotypic complementation (N. Ishii, A. Nakanishi, M. Yamada, M. H. Macalalad, and H. Kasamatsu, J. Virol. 68:8209-8216, 1994), in which an NLS-defective Vp1 could localize to the nucleus in the presence of wild-type minor capsid proteins Vp2 and Vp3. This approach made it possible to dissect the role of the bifunctional Vp1 NLS-DBD in virion assembly in the nucleus. Mutants of the viable nonoverlapping SV40 (NO-SV40) DNA NLSm1, NLSm2, and NLSm1. 2 replicated normally following transfection into host cells and produced capsid proteins at normal levels. All mutant Vp1s were able to interact with Vp3 in vitro. The mutants NLSm1 and NLSm1. 2 were nonviable, and the mutant Vp1s unexpectedly failed to localize to the nucleus though Vp2 and Vp3 did, suggesting that the mutated NLS1 acted as a dominant signal for the cytoplasmic localization of Vp1. Mutant NLSm2, for which the mutant Vp1's nuclear localization defect was complemented by Vp2 and Vp3, displayed a 5,000-fold reduced viability. Analysis of NLSm2 DNA-transfected cell lysate revealed a 10-fold reduction in the level of DNase I-protected viral DNA, and yet virion-like particles were found among the DNase I-resistant material. Collective results support a role for Vp1 NLS2-DBD2 in the assembly of virion particles. The results also suggest that this determinant can function in the infection of new cells.

Retinoblastoma-binding Protein 2 (Rbp2) Potentiates Nuclear Hormone Receptor-mediated Transcription

Retinoblastoma-binding protein 2 (Rbp2) was originally identified as a retinoblastoma protein (RB) pocket domain-binding protein. Although Rbp2 has been shown to interact with RB, p107, TATA-binding protein, and T-cell oncogene rhombotin-2, the physiological function of Rbp2 remains unclear. Here we demonstrate that Rbp2 not only binds to nuclear receptors (NRs) but also enhances the transcription mediated by them. Rbp2 interacts with the DNA-binding domains of NRs and potentiates NR-mediated transcription in an AF-2-dependent manner. Both the N-terminal and C-terminal domains of Rbp2 are critical for the transactivation activity of Rbp2 on NRs. The C terminus is the NR-interacting region. In addition, RB functions in maximizing the effect of Rbp2 on the transcription by NRs. These results suggest that Rbp2 is a coregulator of NRs and define a potential role for Rbp2 in NR-mediated transcription.

Retinoblastoma protein is functionally distinct from its homologues in affecting glucocorticoid receptor-mediated transcription and apoptosis

The cell cycle regulator, retinoblastoma protein, is known to potentiate glucocorticoid receptor-activated transcription through the interaction of its pocket domain with the transcription coactivator, hBRM. We now show that glucocorticoid receptor-induced apoptosis is also dependent on both the retinoblastoma protein and hBRM. p107 and p130, which share extensive sequence homology with the pocket domain of the retinoblastoma protein but not its N-terminal region, also interact with hBRM but do not support either glucocorticoid receptor-dependent activity. This difference arises from the divergent N-terminal domain of the retinoblastoma protein, which, when fused to the pocket domains, confers upon p107 and p130 the ability to influence glucocorticoid receptor activities. This effect probably results from the promotion of glucocorticoid receptor-targeted chromatin remodeling by the hBRM-containing SWI/SNF complex because the N-terminal domain of the retinoblastoma protein enhances glucocorticoid receptor-hBRM interactions. These results highlight that, besides the interaction between hBRM and the pocket domain of RB, the N-terminal region of the retinoblastoma protein is also essential for glucocorticoid receptor-induced apoptosis and the potentiation of glucocorticoid receptor-mediated transcription and provide a basis for functional distinction between the retinoblastoma protein and its homologues.

Action of glucocorticoids to antagonise cisplatin-induced acute and delayed emesis in the ferret

Cisplatin 5 mg/kg, i.p. induced an acute (day 1) and delayed (days 2 and 3) emetic response in the ferret that was used to investigate the potential anti-emetic activity of several glucocorticoids. Betamethasone (0.3-3 mg/kg, i.p.) reduced the emesis occurring during the initial 0-24-h period by 71.1-99.5% (P<0.05). The action of methylprednisolone (1.0-10.0 mg/kg, i.p.) and hydrocortisone (1.0-30.0 mg/kg, i.p.) could not be assessed because the controls exhibited weak emetic responses and dexamethasone produced a non-significant 64.0% reduction at 0.3 mg/kg (P>0.05). However, all glucocorticoids dose-dependently reduced retching+vomiting during the subsequent 24-56-h period. The rank order of anti-emetic potency was betamethasone (ID(80)<0.3 mg/kg)>/=dexamethasone (ID(80)=0.32 mg/kg)>methylprednisolone (ID(80)=0.66 mg/kg)&z.Gt;hydrocortisone (ID(80)>30 mg/kg). Dexamethasone was ineffective to antagonise the retching+vomiting response during the 24-56-h period when the administration was delayed until 24 h post-cisplatin injection. None of the glucocorticoids reduced the retching+vomiting response occurring during the 56-72-h period. In conclusion, the rank order of anti-emetic potency suggests that inflammation, or mediators of inflammation, contribute to the retching+vomiting response induced by cisplatin.

The Mediterranean score of dietary habits in Chinese populations in four different geographical areas

OBJECTIVE

To compare the dietary intake of Chinese people living in Pan Yu, Hong Kong, San Francisco and Sydney with respect to cardiovascular health, using the Mediterranean diet score, examining the effects of age, gender, urbanization and acculturation on the diet score.

SUBJECTS

A total of 500 men and 510 women in Hong Kong were recruited as a territory-wide stratified random sample. Subjects were recruited in response to local advertisements for the other three sites: Pan Yu, 58 men, 95 women; San Francisco, 166 men, 192 women; Sydney, 95 men, 73 women.

METHOD

Food-frequency questionnaire over a 7 week period. A high/healthy score was taken as > or =4 for men and >3 for women, representing a dietary pattern beneficial for cardiovascular health.

RESULTS

In Hong Kong, more women in the middle age group (35-54) had a high score than other age groups, and overall more women had high scores than men. In comparing the four geographical regions, Pan Yu had the highest number of subjects with high score, and Hong Kong had the lowest. With the exception of the younger population and men in Hong Kong, the percentage of the population with a high score in all sites is greater than among elderly Greeks consuming a more traditional heart-healthy Mediterranean diet.

CONCLUSION

Considerable variations in Chinese dietary patterns exist with respect to age, gender and geographic location. Overall, the Chinese diet is comparable to the Mediterranean diet and may be expected to have similar health benefits that have been documented for the traditional Mediterranean diet.

Determination of the major isosteroidal alkaloids in bulbs of Fritillaria by high-performance liquid chromatography coupled with evaporative light scattering detection

A new direct HPLC analytical method using evaporative light scattering detection coupled with a low-temperature adapter for the simultaneous determination of the major biologically active isosteroidal alkaloids in Bulbus Fritillariae, a commonly used antitussive traditional Chinese medicinal (TCM) herb, has been developed. The simultaneous separation of eight Fritillaria alkaloids was achieved on a reversed-phase C8 column with an isocratic mobile phase system consisting of acetonitrile-methanol-water (66.5:3.5:30, v/v) containing 0.006% triethylamine. This method provides good reproducibility and sensitivity for the quantification of six major isosteroidal alkaloids, namely peimissine, verticine, verticinone, imperialine, isoverticine and ebeiedine in different Fritillaria species with overall intra- and inter-day precision and accuracy of less than 11% and higher than 90%, respectively. The assay was successfully utilized to quantify the major biologically active alkaloids in five Fritillaria species. The results demonstrate that this method is simple, selective, and suitable for the quality control of this commonly used antitussive TCM herb, Bulbus Fritillariae. reserved.

Sensitivity to Fas-mediated apoptosis is determined below receptor level in human vascular smooth muscle cells

Despite Fas expression, many cells resist Fas-induced apoptosis. Although differences in surface Fas expression can explain Fas resistance, multiple proteins below receptor level also inhibit Fas-induced apoptosis. To examine the mechanism of Fas resistance, we studied Fas-induced apoptosis in human medial vascular smooth muscle cells (VSMCs) from healthy coronary arteries. VSMCs showed marked heterogeneity to Fas-induced apoptosis, exhibiting both Fas-resistant (98.1+/-2.3% viable, n = 4, P = NS) and Fas-sensitive (31.3+/-2.6% viable, n = 3, P<0.01) cells. Fas-resistant VSMCs expressed surface Fas and could recruit RIP, indicating that functional receptor complexes were formed. However, Fas-resistant cells showed reduced expression of FADD, Fas ligand, and caspases 3, 7, and 8 and increased expression of FLIP and c-IAP-1. Fas-induced apoptosis was associated with cleavage of caspase 3 and blocked by inhibitors of caspase 3 or 8 but not caspase 1, 6, or 7. Selective inhibition of caspase 3 or 8 by antisense transfection inhibited Fas-induced apoptosis, but their reexpression could not rescue the Fas-resistant phenotype. In vivo, medial VSMCs showed marked heterogeneity of expression of caspase 3. We conclude that Fas sensitivity is determined not only by expression of surface Fas but by differential expression of Fas-signaling proteins below receptor level. Subpopulations of cells within the same tissue have different sensitivities to apoptosis, determined by expression of specific death-signaling proteins.

Case management in the Community Psychiatric Nursing Service in Hong Kong: describing the process

PURPOSE

To explore the roles, functions, and work practices of case managers and their perceptions on the implementation of case management in the Community Psychiatric Nursing Services.

METHODS

A qualitative descriptive approach was used. Data were collected from daily reports, field observations, reflective diaries, and small group interviews.

FINDINGS

The study showed the work practices of case managers were more intensive compared to the conventional community psychiatric nursing practice, and there was more involvement of clients and their family in the treatment process. Case managers identified liaison, coordination, supportive and family counseling, and teaching practical living skills as their important roles.

CONCLUSIONS

This study provides valuable information in understanding the process of case management and contributed to the development of case management as a care delivery model in Hong Kong.

Comparison of a commercial enzyme-linked immunosorbent assay with immunofluorescence and complement fixation tests for detection of Coxiella burnetii (Q fever) immunoglobulin M

A commercially available enzyme-linked immunosorbent assay (ELISA) for the diagnosis of Q fever (PanBio Coxiella burnetii immunoglobulin M [IgM] ELISA, QFM-200) was compared to the indirect fluorescent antibody test (IFAT) for C. burnetii IgM and the complement fixation test (CFT). The ELISA demonstrated 92% agreement with the reference method (IFAT), and gave a sensitivity of 99% (69 of 70 samples) and a specificity of 88% (106 of 121). Specificity can be increased with confirmation by IFAT. CFT was found to have a specificity of 90% (107 of 119), although it was lacking in sensitivity (73%; 51 of 70). No cross-reactivity was observed in the ELISA with serum samples from patients with mycoplasma (n = 6), chlamydia (n = 5), or legionella (n = 4) infections, although 2 of 5 patients with leptospirosis and 1 of 4 samples containing rheumatoid factor (RF) demonstrated positive results in the ELISA. Results indicate that the performance of the PanBio C. burnetii (Q fever) IgM ELISA (F = 187) is superior to that of CFT (F = 163), and consequently the ELISA should be a useful aid in the diagnosis of acute Q fever.

Simultaneous determination of seven major isosteroidal alkaloids in bulbs of Fritillaria by gas chromatography

The present paper describes the development of a most simple, sensitive, and specific gas chromatographic method to date, for the direct determination of seven major bioactive isosteroidal alkaloids, namely ebeiedine, ebeiedinone, ebeienine, hupehenine, isoverticine, verticine, verticinone and imperialine, in Fritillaria species, a commonly used antitussive traditional Chinese medicinal (TCM) herb. In the present study, a commercially available Supelco SAC-5 capillary column (30 m x 0.25 mm, 0.25 microm) specifically designed for the analysis of steroids was utilized for the direct determination of Fritillaria alkaloids. Calibration curves were obtained by spiking authentic compounds and the internal standard (solanidine) into herbal samples prior to extraction. Extraction was conducted simply by shaking the pre-alkalized diethyl ether solution (5.0 ml) containing dried herb (0.1 g) for 2 h. All calibration curves showed good linear regressions (r2>0.995) within test ranges. The assay was reproducible and accurate with the overall intra- and inter-day variation and accuracy of less than 10% and more than 90%, respectively. The developed GC method was successfully utilized to analyze seven major bioactive alkaloids in seven Fritillaria species, and the results demonstrate that this direct GC analytical method is suitable for the quality control of this commonly used antitussive TCM herb.

Implementing contract learning in a clinical context: report on a study

This paper reports on a study of the implementation and evaluation of learning contracts in a clinical context for a group of students who were in their third year of study in a pre-registration bachelor of nursing degree programme in Hong Kong. A learning contract was implemented as a learning tool in the students' clinical placement in mental health nursing. An action research approach was used in this study. Data were collected from questionnaires and interviews with students and clinical instructors. Results showed that students and clinical instructors generally agreed that there was an increase in students' autonomy and motivation in learning with the use of a learning contract. It also increased the sharing between students and clinical instructors. The findings of the questionnaire and interviews supported each other. However, the lack of experience in using contract learning and the limited time in the clinical areas created difficulties for both students and clinical instructors. Despite the limitations, contract learning is considered beneficial to students' learning and has the potential to be used in clinical learning.

Prior topical anesthesia reduces time to full cycloplegia in Chinese

PURPOSE

To investigate the effect of prior anesthesia on the time to full cycloplegia in young Chinese subjects.

METHODS

The amplitude of accommodation was monitored over a 50-minute interval after the application of 1% cyclopentolate hydrochloride with a pretreatment of 0.4% benoxinate (oxybuprocaine) or 0.9% saline solution (control). Using a nonlinear mathematical model, the rate of accommodative loss (k) and the time required for 95% of total cycloplegia (T95%) were determined.

RESULTS

Statistical analysis revealed a significantly faster rate of accommodative loss (P < .0001) after prior anesthesia (0.129 +/- 0.05) compared with the controls (0.103 +/- 0.04). T95% was noted at 26.43 +/- 10.22 minutes after prior anesthesia, which was significantly shorter (P < .0001) than that after the saline treatment (35.28 +/- 16.51 minutes).

CONCLUSIONS

Prior application of topical anesthetic can shorten the time to full cycloplegia for people, such as the Chinese, with dark irides.

Pre-column derivatization and gas chromatographic determination of alkaloids in bulbs of Fritillaria

A method of precolumn derivatization GC with FID detection was developed for a simultaneous analysis of five major steroidal alkaloids of Fritillaria species, namely ebeiedine, ebeiedinone, verticine, verticinone and imperialine. Derivatization was carried out by trimethylsilylation of the hydroxyl-containing Fritillaria alkaloids to the corresponding trimethylsilylates with trimethylsilylimidazole. Reaction conditions were optimised and the alkaloids derivatives were characterised by on-line GC-MS. The validated GC method demonstrated a good linearity at the sampling ranges used. This analytical method is simple, convenient and reproducible. The developed assay was successfully applied to the determination of the major pharmacologically active alkaloids in three commonly used antitussive Fritillaria species: F. cirrhosa, F. thunbergii and F. pallidiflora.

Laparoscopic exploration in the management of retroperitoneal masses

BACKGROUND AND OBJECTIVES

The isolated finding of a retroperitoneal mass (RM) often represents a diagnostic challenge. Image-guided biopsy is frequently inadequate for diagnosis. With increasing experience, the use of laparoscopy for exploration of an indeterminate RM may provide a minimally invasive alternative to open exploration. Herein, we present a retrospective review of our initial four laparoscopic explorations, comparing our experience to four contemporary open explorations for an RM.

PATIENTS AND METHODS

From July 1995 to January 1998, four patients, aged 50 to 62 years old, with an RM of undetermined etiology underwent laparoscopic exploration. Another four patients underwent open exploration at the same hospital. The medical records of these patients were reviewed.

RESULTS

The tumors were smaller in the laparoscopic group, averaging 3.7 cm (range 2-6 cm) vs 6.5 cm (range 1-10 cm) in the open group. A definitive diagnosis was obtained for all eight patients. Postoperative complications were observed in one of the laparoscopic explorations, and in three of the open explorations; there was no operative mortality. The blood loss (90 vs 440 ml), fall in hematocrit (5.1 vs 7.8%), time to resumption of a regular diet (3 vs 5 days), amount of morphine sulfate equivalents required for analgesia (128 mg vs 161 mg), time to ambulation (2.3 vs 6 days) and hospital stay (4.8 vs 6 days) were all less among the laparoscopy patients. However, the operative time was longer for the laparoscopic procedure; this time included stent placement and patient repositioning in addition to the time for laparoscopic excision of the mass (7.8 vs 4.3 hours).

CONCLUSION

Laparoscopic exploration appears to be a viable alternative to open exploration in patients presenting with a retroperitoneal mass. It is as effective as an open procedure and provides benefits with regard to patient morbidity and convalescence. However, operative time for this laparoscopic procedure is lengthy.

The use of critical pathways in caring for schizophrenic patients in a mental hospital

To provide quality health care and at the same time, to control cost, literature suggests that using critical pathways as a tool can enhance resource management, increase collaborative practice, and benefit patient care. This study describes the processes of developing a critical pathway in caring for schizophrenic patients in a mental hospital in Hong Kong. The perceived benefits and difficulties in using the critical pathway are discussed from a nursing perspective. Nurses believed that the use of critical pathways could improve the coordination and effectiveness of care. Also, nurses' autonomy and professional status improved. However, inadequate knowledge and resistance from other disciplines were barriers to the implementation. Recommendations are given to overcome the barriers.

Political participation in Hong Kong: a study

AIMS

The aim of this study was to investigate nurses' level of political participation and their perception of political efficacy.

METHODOLOGY

This is a descriptive study. A self-completed questionnaire survey was conducted. Some items in the adopted questionnaire were modified to suit the Hong Kong situation.

SAMPLES

A convenience sample was used. Three hundred and fifty registered nurses that were studying nursing degree programmes in the three universities in Hong Kong were invited to participate in the study.

FINDINGS

Three hundred and eleven registered nurses completed the questionnaire. The findings showed that there were some positive signs of both political awareness and participation in nurses. However, political activities were mainly confined to voting in general elections. Attempts to influence politicians were not evident. Subjects generally have low political efficacy, and they did not feel that nurses had the power to influence the government's policy. The results of this study are discussed in terms of the barriers to nurses' political participation and the recommendations for nursing professional development.

Human recombinant single-chain antibody fragments, specific for the hypervariable region 1 of hepatitis C virus, from immune phage-display libraries

The hypervariable region 1 (HVR1) of hepatitis C virus (HCV) may contain a potential neutralization site and the generation of human single-chain antibody fragments (scFv) to HVR1 may therefore provide a useful tool for the study of HCV. In this report, we have isolated and characterized three anti-HVR1 scFv clones from two patient-derived phage-displayed libraries and HCV HVR1 peptides. scFv S52/20 and S53/6 were selected with serologically cross-reactive HVR1 peptides. scFv p3f10 was obtained by screening the library from patient MH with an autologous HVR1 peptide. Nucleotide sequencing showed that the VH chains and Vkappa chains of all three scFv antibodies were derived from VH3 and Vkappa1 family germline V-genes, respectively. The specificity and affinity of the recombinant scFv antibodies were examined by enzyme-linked immunosorbent assay (ELISA) and an affinity biosensor, using HVR1 peptides. S52/20 scFv binding to S52 HVR1 peptide was blocked by preincubation with soluble peptide S52 and was partially competed by one of three HCV-infected patient sera. In addition, scFv S52/20 blocked the binding of HCV-susceptible Molt-4 cells to immobilized S52 peptide. This study demonstrates that recombinant human scFv antibodies to HCV HVR1 can be produced in vitro and directly confirms that HVR1 of HCV elicits highly specific antibodies. The very high specificity of these antibodies to HVR1 may limit their potential use in passive immunization therapy against HCV, and further engineering of the scFvs needs to be performed to generate broad-spectrum blocking scFvs.

The continuum-of-addiction: cigarette smoking in relation to price among Americans aged 15-29

We studied the relationship between current cigarette smoking and price among 34145 respondents, aged 15-29 years, to the 1992-1993 Tobacco Use Supplements to the Current Population Survey. The price elasticity of current smoking varied inversely with age: -0.831 (S.E. 0.402) for ages 15-17; -0.524 (S.E. 0.256) for ages 18-20; -0.370 (S.E. 0.188) for ages 21-23; -0.202 (S.E. 0.175) for ages 24-26; and -0.095 (S.E. 0.157) for ages 27-29. In response to higher prices, older youth were more likely to reduce the number of cigarettes smoked per day than to quit entirely. Among 15-17-year-olds, smoking cigarettes 'some days' was more sensitive to price than smoking 'every day'. Cigarette smoking was inversely related to the prices of premium brands, but not discount brands.

Cell surface trafficking of Fas: a rapid mechanism of p53-mediated apoptosis

p53 acts as a tumor suppressor by inducing both growth arrest and apoptosis. p53-induced apoptosis can occur without new RNA synthesis through an unknown mechanism. In human vascular smooth muscle cells, p53 activation transiently increased surface Fas (CD95) expression by transport from the Golgi complex. Golgi disruption blocked both p53-induced surface Fas expression and apoptosis. p53 also induced Fas-FADD binding and transiently sensitized cells to Fas-induced apoptosis. In contrast, lpr and gld fibroblasts were resistant to p53-induced apoptosis. Thus, p53 can mediate apoptosis through Fas transport from cytoplasmic stores.