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Background: In advanced nasopharyngeal carcinoma (NPC), biomarkers may help predict survival., Methods: Tumoral expression of ataxia-telangiectasia mutated (ATM), thymidylate synthetase (THMS), and ribonucleotide reductase subunit M1 (RRM1), was correlated with survival in patients with nonmetastatic NPC using quantitative fluorescence immunohistochemistry with automated quantitative digital image analysis., Results: Of the 146 patients included, 58 patients (40%) received concurrent chemoradiation therapy; the remainder was treated with radiation. Overall survival (OS) at 5 years was 71% (95% confidence interval [CI], 62% to 78%); disease-free survival (DFS) was 48% (95% CI, 39% to 57%). OS worsened for increasing values of ATM (hazard ratio [HR], 2.83; 95% CI, 1.01-7.94; p = .049) for values greater than the 75th percentile compared to less than the 25th percentile, but improved for tumors with higher THMS levels (HR, 0.44; 95% CI, 0.20-0.94; p = .033) for values greater than the 25th percentile compared to less than or equal to the 25th percentile. RRM1 was not associated with OS (p = .748). No biomarkers were associated with DFS., Conclusion: In our cohort, relative overexpression of ATM and low THMS levels were associated with worse OS. © 2015 Wiley Periodicals, Inc. Head Neck 38: E384-E391, 2016., (© 2015 Wiley Periodicals, Inc.)

Aberrant Notch activity is oncogenic in several malignancies, but it is unclear how expression or function of downstream elements in the Notch pathway affects tumor growth. Transcriptional regulation by Notch is dependent on interaction with the DNA-binding transcriptional repressor, RBPJ, and consequent derepression or activation of associated gene promoters. We show here that RBPJ is frequently depleted in human tumors. Depletion of RBPJ in human cancer cell lines xenografted into immunodeficient mice resulted in activation of canonical Notch target genes, and accelerated tumor growth secondary to reduced cell death. Global analysis of activated regions of the genome, as defined by differential acetylation of histone H4 (H4ac), revealed that the cell death pathway was significantly dysregulated in RBPJ-depleted tumors. Analysis of transcription factor binding data identified several transcriptional activators that bind promoters with differential H4ac in RBPJ-depleted cells. Functional studies demonstrated that NF-κB and MYC were essential for survival of RBPJ-depleted cells. Thus, loss of RBPJ derepresses target gene promoters, allowing Notch-independent activation by alternate transcription factors that promote tumorigenesis., (© 2015 Kulic et al.)

Purpose: Aberrant expression of proteins involved in epithelial-to-mesenchymal transition have been described in various cancers. In this retrospective study, we sought to evaluate E-cadherin, β-catenin and vimentin protein expression in non-metastatic nasopharyngeal (NPC) patients treated with curative intent, examine their relationship with each other, and with clinical outcome measures., Methods: Pre-treatment formalin-fixed paraffin-embedded biopsies of 140 patients treated between January 2000 and December 2007 were assembled into a tissue microarray (TMA). Automated quantitative immunohistochemistry (AQUA®) was performed on sequential TMA sections stained with fluorescent-labeled antibodies against E-cadherin, β-catenin and vimentin. Cox proportional hazards regression was used to estimate the effect of cytoplasmic vimentin, cytoplasmic E-cadherin, β-catenin nuclear/cytoplasmic ratio expression on overall survival and disease-free survival., Results: The average age of the patients was 51.7 years (SD=12.1; range 18-85), 66% were male, 71% had a KPS ≥ 90% at the start of treatment and 65% had stage III/IV disease. After adjusting for performance status, WHO and stage, high E-cadherin levels over the 75th percentile were found to produce a significantly increased risk for both a worse overall survival (HR = 2.53, 95% CI 1.21, 5.27) and disease free survival (DFS; HR = 2.14, 95%CI 1.28, 3.59). Vimentin levels over the first quartile produced an increased risk for a worse DFS (HR = 2.21, 95% CI 1.11, 4.38). No association was seen between β-catenin and survival., Conclusion: In this cohort of NPC patients, higher levels of E-cadherin and higher levels of vimentin were associated with worse outcomes. Further work is needed to understand the role of these epithelial mesenchymal transition proteins in NPC.

Purpose: We sought to evaluate the prognostic/predictive value of ERCC1 and XPF in patients with nonmetastatic nasopharyngeal carcinoma (NPC) treated with curative intent., Methods and Materials: ERCC1 and XPF protein expression was evaluated by immunofluorescence combined with automated quantitative analysis (AQUA) using the FL297 and 3F2 antibodies, respectively. ERCC1 and XPF protein expression levels were correlated with clinical outcomes., Results: Patient characteristics were as follows: mean age 52 years (range, 18-85 years), 67% male, 72% Karnofsky performance status (KPS) ≥ 90%, World Health Organization (WHO) type 1/2/3 = 12%/28%/60%, stage III/IV 65%. With a median follow-up time of 50 months (range, 2.9 to 120 months), the 5-year overall survival (OS) was 70.8%. Median standardized nuclear AQUA scores were used as cutpoints for ERCC1 (n=138) and XPF (n=130) protein expression. Agreement between dichotomized ERCC1 and XPF scores was high at 79.4% (kappa = 0.587, P<.001). Neither biomarker predicted locoregional recurrence, DFS, or OS after adjustment for age and KPS, irrespective of stratification by stage, WHO type, or treatment., Conclusions: Neither ERCC1 nor XPF, analyzed by quantitative immunohistochemistry using the FL297 and 3F2 antibodies, was prognostic or predictive in this cohort of NPC patients., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Worldwide, haemophilia is the most common hereditary bleeding disorder. The incidence of haemophilia B, however, is considerably less than haemophilia A and consequently appears to have received less attention in the research literature. This article aims to summarise the available evidence documenting the patient and economic burden associated with haemophilia B and current methods of disease management. Both the immediate and long-term clinical consequences of haemophilia B can have significant implications for patients in terms of functional limitations and diminished health-related quality of life (HRQOL). Evidence demonstrates that primary prophylaxis is the optimal strategy for replacing missing clotting factor IX (FIX) and managing haemophilia B. Use of recombinant FIX (rFIX) over plasma-derived FIX (pd-FIX) is also generally preferred for safety reasons. Prophylaxis using currently available rFIX products, however, requires a demanding regimen of intravenous infusions 2-3 times a week which may have significant implications for adherence and ultimately the long-term efficacy of such regimens. Only limited assessments of the cost-effectiveness of prophylactic versus on-demand FIX treatment regimens have been conducted to date. Prophylaxis, however, is generally more costly as greater quantities of FIX are consumed. Any reduction in FIX replacement dosing frequency is expected to improve patient adherence and contribute to improved clinical outcomes, further supporting the cost-effectiveness of such interventions. Although a rare disease, as economic constraints for healthcare increase, generating further information regarding the key clinical, patient and economic outcomes associated with haemophilia B will be essential for supporting improvements in care for people with haemophilia B.

Background: Rhabdoid tumors (RT) are rare, renal or extrarenal, high-grade malignancies. The cytologic diagnosis may be confirmed if combined with genomic results. In the current study, the authors present the cytologic and ancillary techniques used to diagnose RT in their series of 20 tumors in 13 patients., Methods: Clinical charts as well as cytologic, histologic, karyotypic, and molecular biology results were reviewed., Results: Twelve fine-needle aspirations (FNAs) were performed for primary diagnosis, 7 were to confirm a metastasis, and 1 was to confirm local recurrence. Primary tumors were in the kidney in 7 cases and 13 were extrarenal. Patient age ranged from 5 months to 26 years. There were 7 females and 6 males. FNAs were cell-rich in 16 cases and cell-poor in 4 cases and revealed a mix of atypical spindle-shaped, round, rhabdoid, or epithelioid cells, singly or in clusters. Mitosis and necrosis occasionally were present. The original cytologic diagnosis was malignant in all cases. There were no unsatisfactory or false-negative samples. In the 12 primary tumors, the preliminary FNA diagnosis was RT in 7 cases (58%), rhabdomyosarcoma in 4 cases (33%), and malignant peripheral nerve sheath tumor in 1 case (8%). Karyotypes were available in 6 cases, 3 of which demonstrated chromosome 22 changes. Fluorescence in situ hybridization revealed loss of probe signals for the SMARCB1 gene locus in 5 cases; DNA sequence analysis performed in 9 cases revealed deletions in codons of the SMARCB1 gene in 7 cases and a mutation in 2 cases., Conclusions: The primary diagnosis of RT is possible on FNA. In the current study, 12 of 13 cases were diagnosed by FNA with a combination of clinical information, immunocytochemistry, and molecular analysis., (Copyright © 2010 American Cancer Society.)

Clinical use of tissue microarrays for immunohistochemical analysis of breast biomarkers, namely estrogen receptor, progesterone receptor, and HER2, was instituted in our laboratory in 2008. The method has proved reliable and cost-effective. We report the results of the initial year of testing with this method.

Tissue microarray analysis (TMA) allows multiple analyses on multiple patients on sections from a single paraffin block. Although it is widely used in research and in quality assurance settings, there are few references to its use in clinical practice. This study evaluated TMA assessment of breast biomarkers using immunohistochemical analysis in a clinical histopathology laboratory. Performance parameters, interobserver variability, and concordance between TMA and whole section results were assessed. The arrays had few lost or noninformative cores. A loss of stain intensity occurred in the arrays compared with the whole sections with some but not all antibodies, highlighting the need to validate the staining protocol for each antibody used on TMA sections. With recommended guidelines for specimen selection and reporting, TMA was found to be an economical replacement for whole section analysis for breast biomarkers.

Purpose: To evaluate the clinical impact of pathology review before prostate brachytherapy., Methods and Materials: Original and reviewing pathologists' reports were retrospectively collected from 1323 men treated with prostate brachytherapy between July 1998 and October 2005 at one institution. Statistical analysis was performed pre- and post-January 2002. The clinical impact of pathology review was evaluated., Results: Gleason Score (GS) change (GS(Delta)) occurred in 25.2% (334) of cases; GS increased in 21.6%, decreased in 2.4%, and diagnosed malignancy in 1.2% of cases. Post-2002, concordance in attributed GS improved, with GS(Delta) of 31.9-20.6%, respectively (p<0.001), and a reduction in the average GS(Delta) (p<0.001). The clinical impact was substantial with management changing in 14.8% of cases., Conclusion: Concordance between the original and reviewing pathologists' GS has improved during the study period. Nevertheless, discordance persists in one of five cases. Pathology review remains essential, if treatment decisions hinge on GS.

The immunohistochemistry (IHC) performance of 4 anti-HER-2/neu antibodies was compared with fluorescent in situ hybridization (FISH) analysis of HER-2/neu gene expression in breast cancer patients considered for Herceptin (Trastuzumab) therapy. Interobserver variability in IHC interpretation was measured. Formalin-fixed tissue was received from 24 provincial hospital laboratories. The following anti-Her-2 antibodies were used: DAKO A0485 (polyclonal), Novacastra CB11 (monoclonal), Zymed TAB250 (monoclonal), and DAKO HercepTest (polyclonal). Additional sections were analyzed by FISH (Vysis). Three pathologists blinded to FISH results independently interpreted invasive tumor cell membranous staining on a scale of 0 to +3. The HER-2/neu gene was considered amplified when the FISH signal ratio of HER-2/CEP-17 was > or =2.0. Blocks from all hospitals and of all ages were suitable for IHC and FISH analysis. No interlaboratory analysis variability was noted. The interobserver agreement (kappa) for stain intensity for each antibody was good for 0 and +3 but poor for +1 and +2. Reasonable concordance between IHC and FISH was found with three of the four antibodies. TAB250 was the most sensitive antibody. For the three pathologists, the IHC sensitivities and specificities compared with FISH using 0/+1 as negative and +2/+3 as positive were as follows: A0485, 63-84/95-98; CB11, 63-66/97-98; TAB-250, 82-100/94-95; HercepTest, 59-77/91-93. The positive and negative predictive values varied by stain intensity. Stain scores of 0 and +3 were highly predictive of gene status. Stain scores of +1 and +2 were not sufficiently predictive to classify cases as amplified versus nonamplified. IHC is a reasonable first test to assess HER-2/neu status in patients with breast cancer. For most cases, DAKO A0485, TAB250, and HercepTest adequately predicted gene status. In cases with stain intensity of +1 or +2, the interobserver agreement is poor, and the predictive value is unsatisfactory for clinical use. Additional testing, preferably with FISH, is recommended.

Gene-directed enzyme prodrug therapy (GDEPT) is a refinement of cancer chemotherapy that generates a potent cell-killing drug specifically in tumor cells by enzymatic activation of an inert prodrug. We describe in vivo studies that evaluate the efficacy and safety of intratumoral (i.t.) injection of an adenovirus vector (CTL102) expressing Escherichia coli nitroreductase (NTR) combined with systemic prodrug (CB1954) treatment. A single i.t. injection of CTL102 (7.5 x 10(9) to -2 x 10(10) particles) followed by CB1954 treatment produced clear anti-tumor effects in subcutaneous (s.c.) xenograft models of four cancers that are likely candidates for GDEPT (i.e., primary liver, head and neck, colorectal and prostate). Virus dose-response studies (s.c. liver model) revealed a steep increase and subsequent rapid plateauing of both NTR gene delivery and anti-tumor efficacy. Evidence of minor virus spread (toxicity) was observed in a s.c. head and neck xenograft model. This was eliminated by passive immunization with neutralizing anti-Ad5 antibodies prior to virus injection without reducing the magnitude of the anti-tumor effect. Preexisting anti-Ad5 neutralizing antibodies may therefore be an advantage rather than an issue in the clinical use of this new therapy.

HR325 (2-cyano-3-cyclopropyl-3-hydroxy-N-[3'-methyl-4'(trifluoromethyl)-phenyl]-propenamide) is an immunomodulatory compound through pyrimidine biosynthesis inhibition with antiproliferative properties which was derived from the isoxazol compound A77 1726 [2-cyano-3-cyclopropyl-3-hydroxy-enoic acid (4-trifluoromethylphenyl)-amide]. During studies of the effects on early signal transduction events of this type of compound, it was found that HR325 dose-dependently inhibited adenosine 3',5'-cyclic monophosphate (cAMP) synthesis by Jurkat cells stimulated with prostaglandin E(2), (PGE(2)), cholera toxin (CTX), or forskolin (FKN). The potency of inhibition by HR325 of FKN-stimulated cells (IC(50) 30.4 microM) was approximately 3-fold higher than that of the other agonists (11.6 and 11.7 microM) and was independent of time of preincubation for both PGE(2) and FKN. Interestingly, A77 1726, an analogue of HR325, displayed a markedly different profile of stimulus-dependent potencies. The inhibition of cAMP synthesis by HR325 when stimulated by both PGE(2) and FKN was unaffected by glucose supplementation, in contrast to HR325-inhibited ATP levels, which were restored under such conditions. Further studies revealed that HR325 reduced intracellular ATP levels by uncoupling oxidative phosphorylation, albeit with a 1000-fold lower potency than the antihelmintic drug niclosamide. In addition, glucose supplementation experiments showed that, in contrast to HR325, the niclosamide-mediated reduction of ATP levels was wholly responsible for its inhibition of PGE(2)- and FKN-stimulated cAMP synthesis.

The comet assay is a single-cell gel electrophoresis technique that measures DNA damage in individual cells. Since radiation produces 3-4 times more DNA damage in well-oxygenated cells compared with hypoxic cells, this assay can quantify the fraction of radiation-resistant hypoxic cells found in many solid tumours. This paper summarizes our results with 73 accessible metastatic tumours irradiated with palliative intent. Hypoxic fractions ranged from 0.0 to 0.67 with a mean of 0.15; 62% of these advanced tumours showed a hypoxic fraction > 0.05. Comparisons between two sequential aspirates in 33 tumours gave a slope of 0.92 (r2 = 0.88), suggesting that a single aspirate is generally representative of the tumour. A limitation, however, is that the hypoxic fraction could not be measured in clinical samples given a conventional dose of 2 Gy.

The cytologic and cytogenetic findings of chondroid lipoma, a rare benign tumor of soft tissue, have not been described. This report details the morphologic features of a fine-needle aspiration biopsy specimen and describes a novel cytogenetic finding. The main cytologic features consisted of clustered, variably mature, multivacuolated, hibernoma-like cells enmeshed in a capillary plexus, with a background of chondromyxoid material. Cytogenetic analysis revealed a balanced translocation t (11, 16)(q13;p12-13) distinct from the known translocation involving 16p11 in myxoid and round-cell liposarcoma. The 11q13 breakpoint was previously noted in hibernomas, raising the possibility of a common genetic deregulation.

Background: There are few reports on the cytologic features of small cell carcinoma (SMCC) of the uterine cervix., Methods: The clinical records, histopathology, and available cervical smears from all cases of SMCC of the uterine cervix in the files of the British Columbia Cancer Agency between 1985 and 1997 were reviewed., Results: Cervical smears were available from 11 of 13 identified cases. Six cases had a pretreatment smear containing numerous definitely malignant cells. In the seven cases with reported negative smears, review of the most recent smears detected a missed high grade squamous intraepithelial lesion in one case and rare suspicious epithelial cells in a second case. These two cases were considered to be false-negative smears on review. None of the six malignant smears were diagnosed as SMCC on cervical smears. These smears were reported as malignant epithelial cells, not otherwise specified in three cases and misclassified as adenocarcinoma in three cases. These malignant smears contained cells dispersed as single cells or arranged as loosely cohesive sheets or gland-like aggregates. Tumor cells, ranging from small to large, had extremely pleomorphic, angulated nuclei that were hyperchromatic and showed nuclear molding and smearing. Mitotic figures were common and karyorrhectic debris was identified in all cases., Conclusions: The routine cervical smear is a relatively insensitive and nonspecific method of detecting SMCC. The specific diagnosis of SMCC on cervical smears is difficult. SMCC can mimic inflammatory cells, follicular cervicitis, endometrial cells, endocervical adenocarcinoma, squamous cell carcinoma of small cell type, non-Hodgkin's lymphoma, and other unusual malignant neoplasms. The suspicion of SMCC on a cervical smear should prompt an urgent biopsy to establish the diagnosis and initiate prompt treatment.

The relative anti-inflammatory activities of the immunomodulators HR325 and leflunomide, or its active metabolite A77 1726, were examined by determining potencies in vitro on prostaglandin endoperoxide H synthase (PGHS) and in vivo in rat air pouch inflammation. Nonsteroidal anti-inflammatory drugs (NSAIDs) were used as comparators. HR325 was more potent than A77 1726 as an inhibitor of PGHS in guinea pig polymorphonuclear leukocytes (IC50 = 415 and 4400 nM, respectively) and on isolated ovine PGHS-1 (IC50 = 64 and 742 microM) and PGHS-2 (IC50 = 100 and 2766 microM). In vivo, in rat carrageenan air pouch inflammation, HR325 but not leflunomide at 25 mg/kg inhibited accumulation of leukocytes (48%) and PGE2 (61%). HR325 was also more potent than A77 1726 against human peripheral blood mononuclear cell PGHS-1 [IC50 = 1.6 and 25.6 microM (thromboxane B2 production) or 1.1 and 8 microM (PGE2 production)] and lipopolysaccharide-induced PGHS-2 in human adherent peripheral blood mononuclear cells (IC50 = 435 nM and 9.5 microM) and peripheral blood polymorphonuclear leukocytes (IC50 = 91 nM and 3.2 microM). HR325 had low PGHS-2 selectivity in the human (2.5-12-fold) and was a more potent PGHS-2 inhibitor than naproxen, ibuprofen and piroxicam (28-fold). Assays using endogenous arachidonic acid as substrate yielded IC50 values for NSAIDs that were in general markedly lower than those published for assays using 10 microM substrate. With this approach, piroxicam had reasonable activity on human PGHS-2 (IC50 = 260-290 nM). Only NS398 and flufenamic acid were PGHS-2 selective in the human (90-330-fold and 37-60-fold, respectively); the other NSAIDs were either PGHS-1-selective (naproxen, ibuprofen, flurbiprofen and indomethacin) or nonselective (piroxicam and diclofenac). Inclusion of 10% human plasma reduced HR325 potency against PGHS-1 in human peripheral blood mononuclear cells approximately 32-fold (IC50 = 36 microM). Plasma protein binding further reduced HR325 potency (IC50 = 164 microM) and minimized the difference between HR325 and A77 1726 (IC50 = 292 microM) in a whole blood PGHS assay. Whether the greater activity against human PGHS-2 would allow HR325 to exhibit NSAID-like therapeutic effects in humans remains unclear.

A protein with high affinity (Kd 12 nM) for the immunomodulatory compound A77 1726 has been isolated from mouse spleen and identified as the mitochondrial enzyme dihydroorotate dehydrogenase (EC 1.3.3.1). The purified protein had a pI 9.6-9.8 and a subunit Mr of 43,000. Peptides derived from the mouse protein displayed high microsequence similarity to human and rat dihydroorotate dehydrogenase with, respectively, 35 and 39 out of 43 identified amino acids identical. Dihydroorotate dehydrogenase catalyzes the fourth step in de novo pyrimidine biosynthesis. The in vitro antiproliferative effects of A77 1726 are mediated by enzyme inhibition and can be overcome by addition of exogenous uridine. The rank order of potency of A77 1726 and its analogues in binding or enzyme inhibition was similar to that for inhibition of the mouse delayed type hypersensitivity response. It is proposed that inhibition of dihydroorotate dehydrogenase is an in vivo mechanism of action of the A77 1726 class of compounds. This was confirmed using uridine to counteract inhibition of the murine acute graft versus host response.

Interleukin 1 induced proteoglycan loss from cartilage in vitro was prevented by a biochemical inhibitor of metalloproteinase activity. The inhibitor also partially relieved the inhibition of proteoglycan synthesis caused by interleukin 1. The loss of glycosaminoglycan by rat and human femoral head cartilage in response to human recombinant interleukin 1 beta (rhIL-1 beta) was established, and the modulation of this loss by the metalloproteinase inhibitor U27391 was investigated. Rat femoral head cartilage consistently lost glycosaminoglycan in response to rhIL-1 beta whereas only a proportion (30%) of normal human femoral head cartilage did so. Concentrations of 10-100 mumol/l U27391 inhibited the action of rhIL-1 beta on rat femoral head cartilage, reversing both the loss of glycosaminoglycan and the inhibition of glycosaminoglycan synthesis. U27391 also prevented the reduction in glycosaminoglycan content of those human femoral head cartilage explants responsive to rhIL-1 beta. Metalloproteinase inhibition therefore prevents rhIL-1 beta induced glycosaminoglycan loss by rat and human femoral head cartilage, suggesting that inhibitors of such enzymes may prove to be of therapeutic benefit in erosive diseases in humans.

The mechanism of proteoglycan (GAG) loss from rat femoral articular cartilage (FHC) induced by recombinant human interleukin-1 beta (rhIL-1 beta) in vitro has been investigated. The metalloproteinase inhibitor 1,10-phenanthroline, the serine proteinase inhibitor N alpha-p-tosyl-l-lysine chloromethyl ketone (TLCK), the activator of latent metalloproteinase p-aminophenylmercuric acid (APMA), and an inhibitory metalloproteinase substrate analogue U27391 were tested for their ability to modulate rhIL-1 beta-induced GAG loss and GAG synthesis ([35S]O4 uptake) inhibition. As expected 1,10-phenanthroline inhibited GAG loss, however [35S]O4 incorporation was significantly reduced. TLCK was without effect, and APMA inhibited both parameters. U27391 reversed both the inhibition of [35S]O4 incorporation and GAG loss. It is concluded that the adverse effects on proteoglycan metabolism explain the inhibitory actions of 1,10-phenanthroline and APMA, whilst the action of TLCK may indicate that serine proteinases are not involved in the activation of latent metalloproteinase. U27391 exhibited chondroprotective activity and confirmed the induction of either metalloproteinases such as stromelysin or collagenase by rhIL-1 beta.

The effects of the imidazobenzodiazepine Ro 15-4513 in combination with three CNS depressants (ethanol, benzodiazepine agonists and pentobarbital) were examined in three different experiments. Full antagonism of classical benzodiazepines by Ro 15-4513 was seen in all three situations. Partial antagonism of ethanol occurred in the pull up test of muscle relaxation in rats, but not in the inhibition of ultrasounds produced in rat pups by mild stress. The depressant effect of ethanol on twitching of the urethane-anaesthetised rat suprahyoid muscles was reversed. No attenuation of the effects of pentobarbital was seen in any test.

Sixty-five patients underwent craniotomy for brain tumors; of these 35 had glioblastoma multiforme (GM). The GM cases, as a group, showed significantly higher serum titers for herpesvirus type 1 (HSV-1) neutralizing antibodies (NT) than the non-glioblastoma cases. Both the GM group and the pituitary adenoma group had high levels of HSV-1 serum antibodies with the enzyme-linked immunosorbent assay (ELISA). These data, combined with other evidence, lead us to speculate that HSV-1 infections may be associated with certain brain tumors in humans. However, coincidental causes for these elevated HSV-1 titers must be ruled out.

It was considered that the fall in lung function seen after exposure to cotton dust may be attributable in part to the activity of arachidonic acid metabolites, such as leucotrienes as well as to the more established release of histamine by cotton dust. However, we found that cotton and barley dusts elicited poor release of arachidonic acid from an established macrophage like cell line compared with that observed with other organic dusts. In the experimental animal, pulmonary cellular responses to both cotton and barley dust were similar to those evoked by moldy hay and pigeon dropping dusts, although after multiple doses a more severe response was seen to cotton and barley. Since both moldy hay and pigeon droppings elicit a greater arachidonic acid release than cotton or barley, a role for arachidonic acid in inducing the cellular response is less likely than other factors. There are limitations to our conclusions using this system, i.e., the arachidonic acid may be released in a nonmetabolized form, although it is noted that the two dusts with the greatest arachidonic acid release produce their clinical responses in humans largely by hypersensitivity mechanisms.

A subunit virion envelope vaccine of herpes simplex virus type 1 was evaluated for its ability to protect labially infected mice from development of the primary herpetic lesion, encephalitic death, and latent virus infection in the trigeminal ganglion. Several adjuvants, including aluminum hydroxide and polyriboinosinic acid-polyribocytidylic acid complexed with poly-L-lysine and carboxymethyl cellulose were investigated for their ability to enhance protection of the subunit vaccine and were compared in effectiveness with complete Freund adjuvant. The subunit vaccine was demonstrated to be immunogenic, as shown by development of antibody detectable by an enzyme-linked immunosorbent assay. The humoral immune response was correlated with protection from herpetic encephalitis and, at a lower degree, with prevention of the appearance of primary herpetic lesions and acceleration of lesion resolution. The efficacy of the vaccine was most apparent in protecting mice from encephalitic death. To reduce or prevent the development of latent infection was most difficult, but was achieved with some vaccine regimens. Repeated administrations of vaccine with adjuvant were required for this protection. The most effective adjuvant was complete Freund adjuvant, but several synthetic adjuvants were effective, particularly aluminum hydroxide and the polyriboinosinic-polyribocytidylic acid-poly-L-lysine-carboxymethyl cellulose immunoadjuvant.

The kinetics of appearance of five humoral antibody responses (micro-neutralization assay [NT], complement fixation [CF], enzyme-linked immunosorbent assay [ELISA], radioimmunoassay [RIA], antibody-dependent cell-mediated cytotoxicity [ADCC]), were compared during labial infection of BALB/c mice with herpes simplex virus type 1 strain Patton. The ELISA/RIA antibody responses were present in most mice by day 5 after infection, at the beginning of the herpetic lip lesions; antibody effective in ADCC showed identical early kinetics. In contrast, NT/CF antibodies were not detected in most mice until day 10, at the time of resolution of the herpetic lip lesions. The humoral immune responses persisted for at least 6 months after infection. The NT and CF responses were closely correlated in time of appearance and titers (r = 0.9), as were the ELISA and RIA responses (r = 0.99). However, there was little correlation between NT/CF and ELISA/RIA responses (r = 0.02). The kinetics of the delayed type hypersensitivity response showed similar kinetics of appearance to the ELISA/RIA/ADCC humoral responses, and peaked similarly, but waned gradually over 2 months. The importance of antibody in protection against labial herpes simplex virus type 1 infection was demonstrated by the ability of passively transferred convalescent serum (that produced a minimum NT titer of 10 in recipient mice) to protect against development of herpetic lesions and death.

This paper describes part of an education experiment at the University of British Columbia at Vancouver.Six final-year medical students spent approximately 12 weeks in a community. Their time was divided between the hospital and various doctors' offices. They answered a simple questionnaire to describe their experiences and commented favourably upon the opportunities for direct patient contact, learning basic skills, informal teaching by both family physicians and consultants, and the variety of work available.They had the opportunity to follow up the progress of the patient and learn the natural history of common illnesses. They achieved their basic objectives. We conclude from their reports and informal conversation that the experiment was successful and recommend other institutions to try similar programs.

Can the medical student benefit from spending time in the offices of community physicians? Eight consecutive final-year medical students visited the offices of 39 physicians, 31 family physicians and eight specialists, in the communities of Richmond and Delta, British Columbia. The students describe the value of their experience, common problems seen, continuity of care, practice variation, opportunities in specialist office practice and the standard of practice observed. We strongly suggest that some medical student instruction must take place in the community to ensure improved patient care from doctors with a reality-based training. All students, whatever their eventual area of work, would benefit from this experience and we recommend that other centres try similar experiments.