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Introduction: Many surgical fellowship programs incorporate robotic surgery, yet not all residency programs offer robotic training for residents. Given the variability of pre-fellowship robotic exposure, the goal of this study was to explore whether standardized robotic skills assessment would be useful to fellows at the start of their training., Methods: In partnership with the Fellowship Council, we surveyed current fellows of accredited Thoracic, Colorectal, HPB, and Advanced GI/MIS/Bariatrics/Foregut Fellowship programs. Main outcome measurements included amount of robotic exposure during residency, fellows' robotic skills at the start of fellowship, and fellows' attitudes towards a standardized skills assessment., Results: In total, 78 fellows completed the survey. Mean percentage of cases performed robotically during fellowship was 38.1% (SD ± 32.25%). From our respondents, 46% had no robotic curriculum during residency and 86.9% felt a standardized robotic curriculum during residency would have been beneficial. When asked if they started fellowship with adequate robotic skills to operate autonomously, 31% strongly agreed, but 24.4% strongly disagreed. The majority of fellows reported their fellowship program did not conduct an assessment of their robotic skills (71.5%), or provide a specific robotic curriculum (75.6%). On the other hand, 73.3% felt a formal proficiency assessment at the start of fellowship would be helpful for individualized support and training., Conclusions: Given the significant variability in resident exposure to robotic surgery, a standardized robotic curriculum during residency would likely be beneficial. Additionally, a robotic skills assessment at the start of fellowship could help provide a tailored training experience for fellows interested in this skillset., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: Hiatal hernia (HH) repairs have been associated with high recurrence rates. This study aimed to investigate if changes in patient's self-reported GERD health-related quality of life (HRQL) scores over time are associated with long-term surgical outcomes., Methods: Retrospective chart reviews were conducted on all patients who had laparoscopic or robotic HH repairs between 2018 and 2022 at a tertiary care center. Information was collected regarding initial BMI, endoscopic HH measurement, surgery, and pre- and post-operative HRQL scores. Repeat imaging at least a year following surgical repair was then evaluated for any evidence of recurrence. Paired t tests were used to compare pre- and post-operative HRQL scores. Wilcoxon ranked-sum tests were used to compare the HRQL scores between the recurrence cohort and non-recurrence cohorts at different time points., Results: A total of 126 patients underwent HH repairs and had pre- and post-operative HRQL scores. Mesh was used in 23 repairs (18.25%). 42 patients had recorded HH recurrences (33.3%), 35 had no evidence of recurrence (27.7%), and 49 patients (38.9%) had no follow-up imaging. The average pre-operative QOL score was 24.99 (SD ± 14.95) and significantly improved to 5.63 (SD ± 8.51) at 2-week post-op (p < 0.0001). That improvement was sustained at 1-year post-op (mean 7.86, SD ± 8.26, p < 0.0001). The average time between the initial operation and recurrence was 2.1 years (SD ± 1.10). Recurrence was significantly less likely with mesh repairs (p = 0.005). There was no significant difference in QOL scores at 2 weeks, 3 months, 6 months, or 1 year postoperatively between the cohorts (p = NS)., Conclusion: Patients had significant long-term improvement in their HRQL scores after surgical HH repair despite recurrences. The need to re-intervene in patients with HH recurrence should be based on their QOL scores and not necessarily based on established recurrence., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: The surgery clerkship has a powerful impact on medical students' attitudes toward surgery. The primary aim of this study was to identify factors that influence current medical student experiences during the surgery clerkship and discern if they have shifted following the COVID pandemic and with a new generation of "Zillennial" students., Materials and Methods: We conducted a qualitative content analysis of medical student surgery clerkship evaluations from 2018 to 2022 at three clinical training sites of our medical school (n = 596). The codes and themes that emerged from the data were then compared between the pre-COVID cohort (pre-March 2020) and post-COVID (post June 2020) cohorts., Results: Our analysis revealed four themes: clerkship factors, educator qualities, surgical culture, and student expectations. Clerkship factors included the overall clerkship organization, preparatory sessions, and having schedule flexibility. The clinical educators had a significant impact on medical student experience by setting expectations and providing actionable feedback. Surgical culture included the team dynamic and professionalism or diversity issues. Students were expected to have clear guidance for their roles, opportunities to shine, and sought meaningful learning. While the themes were consistent between both cohorts, the frequency of codes varied, with more students commenting on flexibility, neglect, and long work hours in the post-COVID cohort., Conclusions: Numerous previously unreported factors impact surgical clerkship experiences, revealing a generational shift in medical student attitudes. These results suggest that educators and their institutions must be proactive in tracking student evaluations to adapt their clerkship curriculum for an optimal educational experience and evolving student expectations., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Introduction: The role of a Department of Surgery (DoS) Vice Chair of Education (VCE) is a relatively new position intended to address the many changes and initiatives in medical education. The primary responsibilities and functions of a surgical VCE are not well described in the literature. This study examines the perceptions of stakeholders and current VCEs to develop a newly established position of VCE within an academic DoS., Methods: We conducted semistructured interviews of 13 faculties in our DoS. Each of these faculties hold the role of fellowship or residency program director. We also interviewed 13 VCEs from other departments within the same hospital system. Transcripts of these interviews were analyzed using reflexive thematic analysis, comparing the data gathered from the two populations., Results: There was a consensus of positivity about the new VCE position by the stakeholders with some residual uncertainty about how it would affect their work. Four themes resulted from analysis of stakeholder interviews including advocacy for education, balance of clinical, research, and educational duties, departmental integration, and faculty development as educators. Three themes were generated from analysis of interviews of VCEs including leverage of experience, framework establishment, and leadership in education., Conclusions: Although exact VCE roles and responsibilities will be department dependent, this study may help other institutions craft their VCE positions and create a framework for understanding important stakeholder views., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Introduction: Medical students historically receive little to no preclinical exposure to surgery and surgical subspecialties. As a result, by the time they reach their clinical clerkship time, students often have already found interest in other specialties. The goal of this study is to utilize the knowledge to action (KTA) implementation framework to design and refine a clinical immersion experience during the second year of medical school., Methods: A total of 94 second-year Harvard Medical School students underwent the surgical immersion experience between 2019 and 2022 (the program was postponed in 2020 due to COVID). The development and refinement of the curriculum were nicely modeled by the KTA implementation framework. We identified a gap in medical student preclinical education, adapted a curriculum for preclinical medical students at Massachusetts General Hospital , selected the curriculum components to provide a high-level overview of surgery, monitored the student experience, and evaluated outcomes using the student surveys. Based on the survey results, inductive thematic analysis was utilized to identify prominent positive and negative themes. The feedback was then used to tailor subsequent iterations of the immersion experience., Results: Eighty-eight medical students completed the survey (RR = 93.6%), and 85% rated the immersion experience as "excellent", 11% "very good", 4% "good", and 0% "fair" or "poor". There was no significant difference in ratings between sessions. Several key themes were identified, including changed perceptions, diversity of surgical fields, teamwork, surgery clerkship preparedness, and the need for more preclinical exposure., Conclusions: Preclinical medical students gave overwhelmingly positive reviews of the surgical immersion experience. A half-day intervention is sufficient to begin changing students' views toward surgery, disproving stereotypes, and even inspiring some to consider a surgical field themselves. In addition, the KTA implementation framework is a useful model for the development and refinement of medical education curricula., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background: HeberFERON is a co-formulation of α2b and γ interferons, based on their synergism, which has shown its clinical superiority over individual interferons in basal cell carcinomas. In glioblastoma (GBM), HeberFERON has displayed promising preclinical and clinical results. This led us to design a microarray experiment aimed at identifying the molecular mechanisms involved in the distinctive effect of HeberFERON compared to the individual interferons in U-87MG model., Methods: Transcriptional expression profiling including a control (untreated) and three groups receiving α2b-interferon, γ-interferon and HeberFERON was performed using an Illumina HT-12 microarray platform. Unsupervised methods for gene and sample grouping, identification of differentially expressed genes, functional enrichment and network analysis computational biology methods were applied to identify distinctive transcription patterns of HeberFERON. Validation of most representative genes was performed by qPCR. For the cell cycle analysis of cells treated with HeberFERON for 24 h, 48 and 72 h we used flow cytometry., Results: The three treatments show different behavior based on the gene expression profiles. The enrichment analysis identified several mitotic cell cycle related events, in particular from prometaphase to anaphase, which are exclusively targeted by HeberFERON. The FOXM1 transcription factor network that is involved in several cell cycle phases and is highly expressed in GBMs, is significantly down regulated. Flow cytometry experiments corroborated the action of HeberFERON on the cell cycle in a dose and time dependent manner with a clear cellular arrest as of 24 h post-treatment. Despite the fact that p53 was not down-regulated, several genes involved in its regulatory activity were functionally enriched. Network analysis also revealed a strong relationship of p53 with genes targeted by HeberFERON. We propose a mechanistic model to explain this distinctive action, based on the simultaneous activation of PKR and ATF3, p53 phosphorylation changes, as well as its reduced MDM2 mediated ubiquitination and export from the nucleus to the cytoplasm. PLK1, AURKB, BIRC5 and CCNB1 genes, all regulated by FOXM1, also play central roles in this model. These and other interactions could explain a G2/M arrest and the effect of HeberFERON on the proliferation of U-87MG., Conclusions: We proposed molecular mechanisms underlying the distinctive behavior of HeberFERON compared to the treatments with the individual interferons in U-87MG model, where cell cycle related events were highly relevant., (© 2023. BioMed Central Ltd., part of Springer Nature.)

The SARS-CoV-2 pandemic resulted in surgical residency and fellowship interviews shifting to a virtual, web-based format. Although virtual interviews have important benefits, this change also brought about new challenges for applicants, including a new interview etiquette and potential difficulty in evaluating and discriminating between programs. The aim of this article is to provide applicants with guidance for every step of their interview process so that they can confidently put forth their strongest performance. Preparing for effective virtual interviewing begins long before the interview day and involves critical self-reflection, practice with mock interviews, optimizing the interview environment, and conducting a technology trial run. During the interview day, standard interview advice for face-to-face interviews remains true for virtual interviews. However, there are a few additional considerations, including minimizing distractions, muting oneself in a group setting, and turning off the camera when stepping away from the screen. After the interview, there are several ways for applicants to elicit more information about the "fit" of different programs of interest. We recommend leveraging personal relationships to ask additional questions and consider visiting select programs in person, if possible. Although our recommendations are not exhaustive, we hope that by following these virtual interview best practices, applicants will be more prepared to present themselves strongly and successfully navigate the virtual interview process., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background: Protein kinase CK2 activity is implicated in the pathogenesis of various hematological malignancies like Acute Myeloid Leukemia (AML) that remains challenging concerning treatment. This kinase has emerged as an attractive molecular target in therapeutic. Antitumoral peptide CIGB-300 blocks CK2 phospho-acceptor sites on their substrates but it also binds to CK2α catalytic subunit. Previous proteomic and phosphoproteomic experiments showed molecular and cellular processes with relevance for the peptide action in diverse AML backgrounds but earlier transcriptional level events might also support the CIGB-300 anti-leukemic effect. Here we used a Clariom S HT assay for gene expression profiling to study the molecular events supporting the anti-leukemic effect of CIGB-300 peptide on HL-60 and OCI-AML3 cell lines., Results: We found 183 and 802 genes appeared significantly modulated in HL-60 cells at 30 min and 3 h of incubation with CIGB-300 for p < 0.01 and FC >  = │1.5│, respectively; while 221 and 332 genes appeared modulated in OCI-AML3 cells. Importantly, functional enrichment analysis evidenced that genes and transcription factors related to apoptosis, cell cycle, leukocyte differentiation, signaling by cytokines/interleukins, and NF-kB, TNF signaling pathways were significantly represented in AML cells transcriptomic profiles. The influence of CIGB-300 on these biological processes and pathways is dependent on the cellular background, in the first place, and treatment duration. Of note, the impact of the peptide on NF-kB signaling was corroborated by the quantification of selected NF-kB target genes, as well as the measurement of p50 binding activity and soluble TNF-α induction. Quantification of CSF1/M-CSF and CDKN1A/P21 by qPCR supports peptide effects on differentiation and cell cycle., Conclusions: We explored for the first time the temporal dynamics of the gene expression profile regulated by CIGB-300 which, along with the antiproliferative mechanism, can stimulate immune responses by increasing immunomodulatory cytokines. We provided fresh molecular clues concerning the antiproliferative effect of CIGB-300 in two relevant AML backgrounds., (© 2023. The Author(s).)

We estimate the euro area output gap by applying the Beveridge-Nelson decomposition based on a large Bayesian vector autoregression. Our approach incorporates multivariate information through the inclusion of a wide range of variables in the analysis and addresses data issues associated with the COVID-19 pandemic. The estimated output gap lines up well with the CEPR chronology of the business cycle for the euro area and we find that hours worked, more than the unemployment rate, provides the key source of information about labor utilization in the economy, especially in pinning down the depth of the output gap during the COVID-19 recession when the unemployment rate rose only moderately. Our findings confirm that labor market adjustments to the business cycle in the euro area occur more through the intensive, rather than extensive, margin., (© 2023 The Author(s).)

Importance: Vitamin D plays an important role in both the innate and adaptive immune systems. It has been shown to contribute to the etiology of T-cell-mediated autoimmune diseases through the upregulation of type 2 anti-inflammatory T helper cells and the suppression of type 1 T helper cells. Noninfectious uveitis is postulated to be caused by immune dysfunction., Objective: To determine whether there is an association between vitamin D levels and noninfectious anterior uveitis., Design, Setting, and Participants: This was a case-control study. We identified patients with and without noninfectious uveitis using the Massachusetts Eye and Ear Infirmary Ocular Inflammation Database and electronic medical records from March 1, 2008, to December 12, 2015, at the Massachusetts Eye and Ear Infirmary Uveitis and Comprehensive Ophthalmology Clinics. One hundred patients with noninfectious anterior uveitis and 100 patients without uveitis were recruited. Patients with noninfectious uveitis were diagnosed by fellowship-trained uveitis specialists after exclusion of infectious causes and neoplastic masquerades of uveitis. All patients included had a total 25-hydroxyvitamin D level recorded. Multivariate regression models were constructed to determine the association between vitamin D levels and the presence of uveitis., Main Outcome and Measure: Presence of noninfectious anterior uveitis., Results: We identified 100 patients (64 white, 8 African American, 25 Asian, and 3 Hispanic) with a mean (SD) age of 51.8 (15.9) years (26 men) and 100 control individuals (58 white, 23 African American, 8 Asian, and 11 Hispanic) with a mean (SD) age of 53.6 (16.2) years (27 men). Hypovitaminosis D was associated with noninfectious uveitis in the univariate analysis (odds ratio, 2.53; 95% CI, 1.42-4.51; P = .002). The association in multivariate regression after adjusting for age, sex, and race/ethnicity was 2.96 (95% CI, 1.60-5.50; P = .001) The odds of developing uveitis were 4% lower for every 1-ng/mL increase in vitamin D level (odds ratio, 0.96; 95% CI, 0.93-0.99; P = .01) in the main multivariate analysis., Conclusions and Relevance: In this retrospective study, lower vitamin D levels were associated with an increased risk of noninfectious anterior uveitis. However, this does not confirm a causal effect.

The anti-apoptotic protein Mcl-1 is highly expressed in castration-resistant prostate cancer (CRPC), resulting in resistance to apoptosis and association with poor prognosis. Although predominantly localized in the cytoplasm, there is evidence that Mcl-1 exhibits nuclear localization where it is thought to protect against DNA damage-induced cell death. The role of Mcl-1 in mediating resistance to chemotherapy-induced DNA damage in prostate cancer (PCa) is not known. We show in human PCa cell lines and in TRAMP, a transgenic mouse model of PCa, that the combination of the antimitotic agent ENMD-1198 (analog of 2-methoxyestradiol) with betulinic acid (BA, increases proteotoxic stress) targets Mcl-1 by increasing its proteasomal degradation, resulting in increased γH2AX (DNA damage) and apoptotic/necrotic cell death. Knockdown of Mcl-1 in CRPC cells leads to elevated γH2AX, DNA strand breaks, and cell death after treatment with 1198 + BA- or doxorubicin. Additional knockdowns in PC3 cells suggests that cytoplasmic Mcl-1 protects against DNA damage by blocking the mitochondrial release of apoptosis-inducing factor and thereby preventing its nuclear translocation and subsequent interaction with the cyclophilin A endonuclease. Overall, our results suggest that chemotherapeutic agents that target Mcl-1 will promote cell death in response to DNA damage, particularly in CRPC.

Interferons (IFNs) are proteins of the family of cytokines. Their antiproliferative function has been taken into account for several clinical therapies against malignant diseases. In this family, IFNs α and γ have demonstrated the highest antitumor effects. HerberPAG® is a new co-formulation with IFNs, α2b and γ. It has been obtained to increase the antiproliferative effect of individual IFNs and decrease their associated toxicity. Glioblastoma multiforme (GBM) is the most common primary brain tumor and one of the most deadly forms of cancer. The objective of the present work is to obtain insights into the regulation of Interferon-STAT-pathways and apoptosis in U87MG, at the transcriptional level. As a pharmacogenomic strategy we quantified mRNAs levels in vitro by quantitative PCR, using the cell line U87MG as a model. Some of the genes involved in the first steps of IFNs signaling pathways (stat1 and stat3) and apoptosis events (tp53, bax, bcl-2, bad, caspase3 (casp3), caspase8 (casp8) and caspase9 (casp9)) were studied. The detected mRNAs expression pattern for stat1and stat3 indicates a higher tumor suppressor activity of HerberPAG® compared to individuals IFNs. The up-regulation of tp53, bax, bad, casp3, casp8 and casp9 genes and the down regulation of bcl-2 gen, after the treatment with HerberPAG® show a pro-apoptotic function. HerberPAG® gene-induced profile shows an advantage in relation to IFN α2b and γ with a higher stat1 expression and a downregulation of bcl-2 which increases bax:bcl-2 ratio. The regulation of genes involved in IFN-STAT-pathways and apoptosis may be the first evidences to explain the increased antiproliferative properties of this co-formulation.

Impaired consciousness in epilepsy has a significant negative impact on patients' quality of life yet is difficult to study objectively. Here, we develop an improved prospective Responsiveness in Epilepsy Scale-II (RES-II) and report initial results compared with the earlier version of the scale (RES). The RES-II is simpler to administer and includes both verbal and non-verbal test items. We evaluated 75 seizures (24 patients) with RES and 34 seizures (11 patients) with RES-II based on video-EEG review. The error rate per seizure by test administrators improved markedly from a mean of 2.01 ± 0.04 with RES to 0.24 ± 0.11 with RES-II. Performance during focal seizures showed a bimodal distribution, corresponding to the traditional complex partial vs. simple partial seizure classification. We conclude that RES-II has improved accuracy and testing efficiency compared with the original RES. Prospective objective testing will ultimately lead to a better understanding of the mechanisms of impaired consciousness in epilepsy., (Copyright © 2012. Published by Elsevier Inc.)

Inhibition of the ubiquitin-proteasome system (UPS) of protein degradation is a valid anti-cancer strategy and has led to the approval of bortezomib for the treatment of multiple myeloma. However, the alternative approach of enhancing the degradation of oncoproteins that are frequently overexpressed in cancers is less developed. Betulinic acid (BA) is a plant-derived small molecule that can increase apoptosis specifically in cancer but not in normal cells, making it an attractive anti-cancer agent. Our results in prostate cancer suggested that BA inhibited multiple deubiquitinases (DUBs), which resulted in the accumulation of poly-ubiquitinated proteins, decreased levels of oncoproteins, and increased apoptotic cell death. In normal fibroblasts, however, BA did not inhibit DUB activity nor increased total poly-ubiquitinated proteins, which was associated with a lack of effect on cell death. In the TRAMP transgenic mouse model of prostate cancer, treatment with BA (10 mg/kg) inhibited primary tumors, increased apoptosis, decreased angiogenesis and proliferation, and lowered androgen receptor and cyclin D1 protein. BA treatment also inhibited DUB activity and increased ubiquitinated proteins in TRAMP prostate cancer but had no effect on apoptosis or ubiquitination in normal mouse tissues. Overall, our data suggests that BA-mediated inhibition of DUBs and induction of apoptotic cell death specifically in prostate cancer but not in normal cells and tissues may provide an effective non-toxic and clinically selective agent for chemotherapy.

Relative gene quantification by quantitative reverse transcription PCR (qRT-PCR) is an accurate technique only when a correct normalization strategy is carried out. Some of the most commonly genes used as reference have demonstrated variation after interferon (IFN) treatments. In this work we evaluated the suitability of seven reference genes (RGs) [glyceraldehyde-3-phosphate dehydrogenase (GAPDH), hydroxymethylbilane synthase (HMBS), β-2Microglobulin (B2M), ribosomal RNA subunits 18S and 28S, tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein, zeta polypeptide (YWHAZ) and the RNA helicase (DDX5)] for use in qRT-PCR assays in the glioblastoma-derived cell line U87MG treated with IFNα, IFNγ or a co-formulated combination of both IFNs (HeberPAG); untreated cell lines were included as control. Data was analyzed using geNorm and NormFinder softwares. The expression stability of the seven RGs decreased in order of DDX5/GAPDH/HMBS, 18S rRNA, YWHAZ, 28S rRNA and B2M. qRT-PCR analyses demonstrated that DDX5, GAPDH and HMBS were among the best stably expressed markers under all conditions. Both, geNorm and NormFinder, analyses proposed same RGs as the least variables. Evaluation of the expression levels of two target genes utilizing different endogenous controls, using REST-MCS software, revealed that the normalization method applied might introduce errors in the estimation of relative quantities. We concluded that when qRT-PCR is designed for studies of gene expression in U87MG cell lines treated with IFNs type I and II or their combinations, the use of all three GAPDH, HMBS and DDX5 (or their combinations in pairs) as RGs for data normalizations is recommended.

The Dengue IgM Capture ELISA (MAC-ELISA) is the immunoenzymatic system recommended by the Pan American Health Organization and the World Health Organization for the serological diagnosis of dengue virus infection due to its high sensitivity, ease of performance, and use of a single acute-phase serum sample. However, tests with this enzyme-linked immunosorbent assay (ELISA) system are time-consuming and require equipment for washing, incubation, and reading of the results. AuBioDOT is a multistep visual diagnostic immunoassay that uses technology based on the immunoglobulin M (IgM) capture ELISA principle. This system uses white polyethylene opaque plates as the solid phase, colloidal gold as the marker, and silver ion amplification. It does not require special equipment, it is totally manually operated, and it can be performed in less than 1 h. The sensitivity and specificity of AuBioDOT for the detection of anti-dengue virus IgM antibodies were studied with a panel of 336 serum samples (150 serum samples from patients with suspected or serologically confirmed dengue virus infection, 186 serum samples from healthy blood donors and patients without dengue virus infection). The results were compared with those obtained by the MAC-ELISA. A sensitivity of 97.7% and a specificity of 97.1% were obtained. The concordance of the two tests was 97.3%, with a kappa index of 0.94. The application of AuBioDOT for the detection of anti-dengue virus IgM antibodies is recommended as an alternative method for the diagnosis of dengue virus infection, both for clinical diagnosis and for seroepidemiological surveillance. The system is useful under field conditions and in laboratories and requires little equipment.

The Fear Survey Schedule-III (FSS-III) was administered to a total of 5491 students in Australia, East Germany, Great Britain, Greece, Guatemala, Hungary, Italy, Japan, Spain, Sweden, and Venezuela, and submitted to the multiple group method of confirmatory analysis (MGM) in order to determine the cross-national dimensional constancy of the five-factor model of self-assessed fears originally established in Dutch, British, and Canadian samples. The model comprises fears of bodily injury-illness-death, agoraphobic fears, social fears, fears of sexual and aggressive scenes, and harmless animals fears. Close correspondence between the factors was demonstrated across national samples. In each country, the corresponding scales were internally consistent, were intercorrelated at magnitudes comparable to those yielded in the original samples, and yielded (in 93% of the total number of 55 comparisons) sex differences in line with the usual finding (higher scores for females). In each country, the relatively largest sex differences were obtained on harmless animals fears. The organization of self-assessed fears is sufficiently similar across nations to warrant the use of the same weight matrix (scoring key) for the FSS-III in the different countries and to make cross-national comparisons feasible. This opens the way to further studies that attempt to predict (on an a priori basis) cross-national variations in fear levels with dimensions of national cultures.

An anti-Hepatitis B virus surface antigen (HBsAg) single chain Fv (scFv) antibody fragment was expressed in Nicotiana tabacum transgenic plants. The 6-histidine tagged scFv was targeted to either the cytosol, apoplast, and vacuole, or for retention in the endoplasmic reticulum. Expression of active scFv was detected by ELISA in fresh leaf material from F I transgenic plant lines representative of the genetic constructs targeting the antibody fragment to the apoplastic fluid (AF-12, 0.031% of the total soluble protein), vacuole (V-20, 0.032% of the total soluble protein), and endoplasmic reticulum (ER-52, 0.22% of the total soluble protein). No scFv was detected by ELISA or western blot in the plants transformed with the cytosol construct. The biologically active scFv was easily purified (to 94-95% purity) from ER-52 and AF-12 plant material using immobilized metal ion affinity chromatography. Recovery estimated from the ER-52 plant line indicates that 15-20 microg of pure active scFv can be obtained per gram of fresh leaf material, on a laboratory scale.