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This case presents a hyperplastic inflammatory mass at the resection site of a colorectal tubular adenoma. A 65-year-old man with a history of alcohol-associated liver cirrhosis, >10 lifetime polyps, and a CHEK2 mutation underwent hybrid endoscopic submucosal dissection of a 3 cm lateral spreading tumor, nongranular, Paris 0-IIa polyp in the ascending colon. Postresection pathology confirmed tubular adenoma with negative margins (R0). Six-month surveillance colonoscopy in the community identified a mass at the resection site, initially suspected to be local recurrence. Repeat colonoscopy demonstrated a mass which appeared inflammatory, with a Kudo type II hyperplastic pit pattern on narrow-band imaging and near-focus magnification. Biopsies confirmed inflammatory hyperplastic polyp. Three months later, surveillance colonoscopy revealed a shrinking polyp with biopsies consistent with hyperplastic histology. Factors such as portal hypertension, CHEK2 mutation, and concurrent gastric hyperplastic polyps may contribute to this phenomenon., (Written work prepared by employees of the Federal Government as part of their official duties is, under the U.S. Copyright Act, a “work of the United States Government” for which copyright protection under Title 17 of the United States Code is not available. As such, copyright does not extend to the contributions of employees of the Federal Government.)

Purpose  To assess how resident and attending ophthalmologists perceive and evaluate ethically controversial scenarios regarding mentorship, authorship, and ethics compliance that may occur during research involving residents. Methods  An online survey was developed and contained 14 controversial vignettes based on common research scenarios that can occur when conducting research with trainees. The scenarios were designed to capture issues regarding three themes: mentorship, authorship, and compliance with ethical guidelines. Resident and attending ophthalmologists at eight military and civilian academic residency programs in the United States were invited to participate. Respondents used a Likert scale to assess the ethicality of the situations in addition to self-reported demographic characteristics. Results  The response rate was 35.6% (77/216), consisting of 37.7% ( n  = 29) residents and 62.3% ( n  = 48) attendings. More attending ophthalmologists responded than residents ( p  = 0.004). Many respondents identified controversies around compliance (67.3%) and authorship (57.1%) as unethical, whereas situations regarding mentorship were largely viewed as neutral to ethical (68.0%). Responses to two scenarios, one regarding mentorship and one regarding authorship, significantly differed between residents and attendings ( p  = 0.001 and p  = 0.022, respectively). Conclusion  Academic ophthalmologists' perceptions of the ethicality of common research scenarios varied. There is a need for more prescriptive guidelines for authorship and mentorship ethics at all training levels to ensure consistency, fairness, and integrity of research., Competing Interests: Conflict of Interest None declared., (The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. ( https://creativecommons.org/licenses/by-nc-nd/4.0/ ).)

Background: Inhalation of fungal spores is a strong risk factor for severe asthma and experimentally leads to development of airway mycosis and asthma-like disease in mice. However, in addition to fungal spores, humans are simultaneously exposed to other inflammatory agents such as lipopolysaccharide (LPS), with uncertain relevance to disease expression. To determine how high dose inhalation of LPS influences the expression of allergic airway disease induced by the allergenic mold Aspergillus niger (A. niger)., Methods: C57BL/6J mice were intranasally challenged with the viable spores of A. niger with and without 1 μg of LPS over two weeks. Changes in airway hyperreactivity, airway and lung inflammatory cell recruitment, antigen-specific immunoglobulins, and histopathology were determined., Results: In comparison to mice challenged only with A. niger, addition of LPS (1 μg) to A. niger abrogated airway hyperresponsiveness and strongly attenuated airway eosinophilia, PAS+ goblet cells and T H 2 responses while enhancing T H 1 and T H 17 cell recruitment to lung. Addition of LPS resulted in more severe, diffuse lung inflammation with scattered, loosely-formed parenchymal granulomas, but failed to alter fungus-induced IgE and IgG antibodies., Conclusions: In contrast to the strongly allergic lung phenotype induced by fungal spores alone, addition of a relatively high dose of LPS abrogates asthma-like features, replacing them with a phenotype more consistent with acute hypersensitivity pneumonitis (HP). These findings extend the already established link between airway mycosis and asthma to HP and describe a robust model for further dissecting the pathophysiology of HP., (© 2021. The Author(s).)

Background: A balance between autonomy and supervision can be difficult to obtain in medical education. In this study, we sought to determine whether the presence and level of supervision of ophthalmology resident outpatient clinic correlates with metrics of resident success, professionalism and stress., Methods: A survey was emailed to all US ophthalmology program directors requesting it be forwarded to PGY4 residents. Questions included whether their program provided a resident-hosted outpatient clinic, and if so, whether residents were mandated to discuss every patient with faculty. Residents were assigned to three categories based on this question (0: no clinic, 1: mandated faculty input, 2: discretionary faculty input). Success metrics included numbers of manuscripts submitted, OKAP scores and success in obtaining fellowships. Professionalism metrics included rating comfort obtaining informed consent, breaking bad news, managing time in clinic, and confidence in providing care in various settings. Residents affirming participation in a continuity clinic also provided perceptions of the level of supervision and how the clinic affected stress., Results: Category 1 residents perceived somewhat too much supervision, while category 2 residents felt that they had somewhat insufficient supervision. The majority of residents in either category did not feel that the continuity clinic affected their overall stress, although those who reported a change in stress usually indicated that the presence of the clinic increased stress. There were no other statistically significant differences between the responses from any category., Conclusions: The presence of a resident-hosted continuity clinic neither adds nor detracts from the success or sense of professionalism of ophthalmology residents. However, when such a clinic is present, the degree of supervision appears to correlate inversely with resident perception of autonomy. These results suggest that the decision of a training program to offer a clinic hosted by residents offering comprehensive continuity care can be informed primarily by faculty and trainee philosophy and personal preferences without comprising education quality, clinical efficiency, residents' perception of stress or their success in fellowship matching.

Objective: To develop a probability model of matching into a US ophthalmology residency program using San Francisco Matching Program (SF Match) data., Design: Retrospective data analysis of de-identified application and matching data., Participants: Registrants for the 2013, 2014, and 2015 ophthalmology residency matches conducted by the SF Match., Methods: Descriptive statistics of candidates, comparison of continuous and categorical variables between matched and nonmatched candidates, and linear regression modeling were performed. A recursive partitioning method was used to create a probability of matching algorithm., Main Outcome Measures: Probability of successfully matching based on quantifiable candidate characteristics., Results: Over the 3-year period, 1,959 individuals submitted an average of 64 applications and received a mean of nine interview invitations. The overall match rate was 71%, with 78% matching at one of their top five choices. Successful matches were more likely to occur in US medical school graduates (78% vs 20%, p < 0.001) and applicants on their first attempt (76% vs 29%, p < 0.001). The association between matching and number of programs applied became negative with > 48 applications. Probability of matching was "high" (> 80%) among US graduates with a step 1 United States Medical Licensing Examination (USMLE)score>243(regardless of number of programs applied to), a step 1 USMLE score of 231 to 243 who applied to at least 30 programs, and first-time applicants with a step 1 score >232. No international medical graduates or repeat applicants had a "high" probability of matching., Conclusions: Although advice must be individualized for each candidate, applicants for ophthalmology residency who fall into a "high" probability of matching group are likely to be successful with applications to 45 or fewer programs. Applying to 80 or more programs should be considered for international medical graduates and/or applicants who are previously unmatched. Modification of the match application data form may allow more detailed analysis of variables such as Alpha Omega Alpha or Gold Humanism Honor Society membership, research activity, and composite evaluation on a standardized letter of recommendation., Competing Interests: Conflict of Interest Dr. Feldon reports personal fees from Association of University Professors of Ophthalmology, outside the submitted work, and is Chair of a Department of Ophthalmology that has a residency training program that could be affected by the information in the article. Dr. Stoner reports support for data analysis from the Association of University Professors of Ophthalmology (AUPO), during the conduct of the study. All the other authors report no conflict of interest.

Background: Atypical antipsychotic agents (AAP) alleviate the symptoms of severe mental health disorders, such as schizophrenia, by antagonizing dopamine and serotonin receptors. Recently, AAP have also been shown to exhibit immunomodulatory properties in the central nervous system (CNS)., Objective: Building on research which demonstrated the ability of the AAP risperidone and clozapine to modify the disease course of experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS), we aimed to more fully investigate the potential of clozapine as a possible treatment for MS., Results: We report that orally administered clozapine significantly reduced the disease severity of EAE in a dose-dependent manner and was effective when administered prophylactically and therapeutically. In comparison to risperidone, quetiapine, and olanzapine, clozapine was the best at reducing disease severity. While clozapine-treated mice had only modest changes to peripheral leukocytes and cytokine responses, these animals had significantly fewer CNS-infiltrating CD4 T cells and myeloid cells. Furthermore, the CNS myeloid cells displayed a less activated phenotype in mice treated with clozapine. Finally, we found that co-administration of clozapine with glatiramer acetate enhanced disease protection compared to either treatment alone., Conclusion: These studies indicate that clozapine is an effective immunomodulatory agent with the potential to treat immune-mediated diseases such as MS.

Rationale: Data about the influence of the type of sedation on yield, complications, and tolerance of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) are based mostly on retrospective studies and are largely inconsistent., Objectives: To determine whether the type of sedation influences the diagnostic yield of EBUS-TBNA, its complication rates, and patient tolerance., Methods: Patients referred for EBUS-TBNA were randomized (1:1) to undergo this procedure under general anesthesia (GA) or moderate sedation (MS). Pathologists were blinded to group allocation., Measurements and Main Results: The main outcome was "diagnostic yield," defined as the percentage of patients for whom EBUS-TBNA rendered a specific diagnosis. One hundred and forty-nine patients underwent EBUS-TBNA, 75 under GA and 74 under MS. Demographic and baseline clinical characteristics were well balanced. Two hundred and thirty-six lymph nodes (LNs) and six masses were sampled in the GA group (average, 3.2 ± 1.9 sites/patient), and 200 LNs and six masses in the MS group (average, 2.8 ± 1.5 sites/patient) (P = 0.199). The diagnostic yield was 70.7% (53 of 75) and 68.9% (51 of 74) for the GA group and MS group, respectively (P = 0.816). The sensitivity was 98.2% in the GA group (confidence interval, 97-100%) and 98.1% in the MS group (confidence interval, 97-100%) (P = 0.979). EBUS was completed in all patients in the GA group, and in 69 patients (93.3%) in the MS group (P = 0.028). There were no major complications or escalation of care in either group. Minor complications were more common in the MS group (29.6 vs. 5.3%) (P < 0.001). Most patients stated they "definitely would" undergo this procedure again in both groups (P = 0.355)., Conclusions: EBUS-TBNA performed under MS results in comparable diagnostic yield, rate of major complications, and patient tolerance as under GA. Future prospective multicenter studies are required to corroborate our findings. Clinical trial registered with www.clinicaltrials.gov (NCT 01430962).

Background: Endoscopic ultrasound (EUS)-guided fine needle aspiration (FNA) with bedside cytopathology is the gold standard for assessment of pancreatic, subepithelial, and other lesions in close proximity to the gastrointestinal tract, but it is time-consuming, has certain diagnostic limitations, and bedside cytopathology is not widely available., Aims: The goal of this study is to compare the diagnostic yield of EUS-guided FNA with on-site cytopathology and EUS-guided core biopsy., Methods: Twenty-six patients with gastrointestinal mass lesions requiring biopsy at a tertiary medical center were included in this retrospective analysis of a prospective cohort. Two core biopsies were taken using a 22 gauge needle followed by FNA guided by a bedside cytopathologist at the same endoscopic session. The diagnostic yield and test characteristics of EUS core biopsy and EUS FNA with bedside cytopathology were examined., Results: The mean number of passes was 3.2 for FNA, and the mean procedure time was 39.4 minutes. The final diagnosis was malignant in 92.3 %. Sensitivity and specificity were 83 % and 100 %, respectively, for FNA, and 91.7 % and 100 %, respectively, for core biopsy. Diagnostic accuracy was 92.3 % for FNA and 84.6 % for core biopsy. The two approaches were in agreement in 88.4 % with a kappa statistic of 0.66 (95 % confidence interval 0.33 - 0.99)., Conclusions: An approach using two passes with a core biopsy needle is comparable to the current gold standard of FNA with bedside cytopathology. The performance of two core biopsies is time-efficient and could represent a good alternative to FNA with bedside cytopathology.

Primary angiosarcoma of the spleen is a rare neoplasm arising from endothelial cells. It is an aggressive neoplasm with a poor prognosis. We report a case of 61-year-old Caucasian man who presented with shortness of breath, anemia, leukocytosis, and thrombocytopenia. Ultrasound Sonogram (US) and Computed Tomography (CT) scans revealed a massively enlarged spleen with numerous enhancing hypodense lesions. The spleen was adherent to the omentum, retroperitoneum, and tail of the pancreas. Image-guided Fine Needle Aspiration (FNA) revealed an atypical spindle cell lesion. Resection of the spleen and attached tail of pancreas was performed. Histological examination and immunohistochemical studies revealed a diffuse vascular malignant neoplasm with features of angiosarcoma. The patient appeared disease free after resection. He died within 5 months of unknown etiology.

We report a case of synchronous primary colonic adenocarcinoma and malignant mesothelioma. A 61-year-old male presented with a six-month history of fatigue and weight loss. An abdominal computed tomography (CT) scan showed a 5.8 cm partially obstructing mass in the cecum with ascites and peritoneal thickening. A biopsy of the large mass showed an adenocarcinoma. Because the patient was clinically thought to be a T4 colon carcinoma with peritoneal metastatic lesions (M1), prior to initiating chemotherapy, a debulking right hemicolectomy was performed. Resection of the colon and ileum revealed a T3N0 colonic mucinous adenocarcinoma and concurrent diffuse malignant peritoneal mesothelioma. Presenting synchronous colonic and peritoneal mesothelial primary malignancies are exceedingly rare but must be considered to prevent incorrect clinical staging.

Bacterial nitroreductase enzymes that can efficiently catalyse the oxygen-independent reduction of prodrugs originally developed to target tumour hypoxia offer great potential for expanding the therapeutic range of these molecules to aerobic tumour regions, via the emerging cancer strategy of gene-directed enzyme prodrug therapy (GDEPT). Two promising hypoxia prodrugs for GDEPT are the dinitrobenzamide mustard PR-104A, and the nitrochloromethylbenzindoline prodrug nitro-CBI-DEI. We describe here use of a nitro-quenched fluorogenic probe to identify MsuE from Pseudomonas aeruginosa as a novel nitroreductase candidate for GDEPT. In SOS and bacteria-delivered enzyme prodrug cytotoxicity assays MsuE was less effective at activating CB1954 (a first-generation GDEPT prodrug) than the "gold standard" nitroreductases NfsA and NfsB from Escherichia coli. However, MsuE exhibited comparable levels of activity with PR-104A and nitro-CBI-DEI, and is the first nitroreductase outside of the NfsA and NfsB enzyme families to do so. These in vitro findings suggest that MsuE is worthy of further evaluation in in vivo models of GDEPT.

Background: The nitro-chloromethylbenzindoline prodrug nitro-CBI-DEI appears a promising candidate for the anti-cancer strategy gene-directed enzyme prodrug therapy, based on its ability to be converted to a highly cytotoxic cell-permeable derivative by the nitroreductase NfsB from Escherichia coli. However, relative to some other nitroaromatic prodrugs, nitro-CBI-DEI is a poor substrate for E. coli NfsB. To address this limitation we evaluated other nitroreductase candidates from E. coli and Pseudomonas aeruginosa., Findings: Initial screens of candidate genes in the E. coli reporter strain SOS-R2 identified two additional nitroreductases, E. coli NfsA and P. aeruginosa NfsB, as being more effective activators of nitro-CBI-DEI than E. coli NfsB. In monolayer cytotoxicity assays, human colon carcinoma (HCT-116) cells transfected with P. aeruginosa NfsB were >4.5-fold more sensitive to nitro-CBI-DEI than cells expressing either E. coli enzyme, and 23.5-fold more sensitive than untransfected HCT-116. In three dimensional mixed cell cultures, not only were the P. aeruginosa NfsB expressing cells 540-fold more sensitive to nitro-CBI-DEI than pure cultures of untransfected HCT-116, the activated drug that they generated also displayed an unprecedented local bystander effect., Conclusion: We posit that the discrepancy in the fold-sensitivity to nitro-CBI-DEI between the two and three dimensional cytotoxicity assays stems from loss of activated drug into the media in the monolayer cultures. This emphasises the importance of evaluating high-bystander GDEPT prodrugs in three dimensional models. The high cytotoxicity and bystander effect exhibited by the NfsB&#95;Pa/nitro-CBI-DEI combination suggest that further preclinical development of this GDEPT pairing is warranted.

Anaphylaxis during anaesthesia is a rare event that in ∼60-70% of cases is secondary to neuromuscular blocking agents. It has been suggested previously that the recent introduction of sugammadex may provide a novel therapeutic approach to the management of rocuronium-induced anaphylaxis. We describe the case of a 33-yr-old female who suffered a severe anaphylactic reaction to rocuronium, presenting with cardiovascular collapse on induction of anaesthesia. After 19 min of traditional management, she was given a bolus of sugammadex 500 mg. This was associated with an improvement in the adverse haemodynamic state. The underlying reasons for this are unclear, but sugammadex may potentially be a useful adjunct in the management of rocuronium-induced anaphylaxis.

Primary biliary cirrhosis (PBC) and autoimmune hepatitis (AIH) overlap syndrome may be found in a significant percentage of patients with either PBC or AIH. However, it is conceivable that most cases of PBC-AIH overlap syndrome are a concurrent manifestation of both diseases which therefore requires treatment of both disease entities. While most cases are found in asymptomatic patients or in patients who have been previously diagnosed with PBC, our patient presented with concurrent PBC and AIH resulting in subfulminant liver failure that responded to treatment with prednisone and ursodeoxycholic acid (UDCA). Extended 4-year follow-up and treatment with UDCA confirmed the diagnosis of PBC and demonstrated serological resolution of AIH.

Background: Transplantable B16 melanoma is widely used as a tumor model to investigate tumor immunity. We wished to characterize the leukocyte populations infiltrating B16 melanoma tumors, and the functional properties of tumor-infiltrating dendritic cells (TIDC)., Materials and Methods: We used the B16 melanoma cell line expressing ovalbumin protein (OVA) to investigate the phenotype and T cell stimulatory capacity of TIDC., Results: The majority of leukocytes in B16 melanoma were macrophages, which colocalized with TIDCs, B and T cells to the peripheral area of the tumor. Both myeloid and plasmacytoid DC populations were present within tumors. Most of these DCs appeared immature, but about a third expressed a mature phenotype. TIDCs did not present tumor-derived antigen, as they were unable to induce the proliferation of tumor-specific CD4+ and CD8+ T cells in vitro unless in the presence of specific peptides. Some presentation of tumor-derived antigen could be demonstrated in the tumor-draining lymph node using in vivo proliferation assays. However, while proliferation of CD8+ T cells was reproducibly demonstrated, no proliferation of CD4+ T cells was observed., Conclusion: In summary, our data suggest that DCs in tumors have limited antigen-presenting function. Inefficient antigen presentation extends to the tumor-draining lymph node, and may affect the generation of antitumor immune responses.

Background: Lagtimes to diagnostic colonoscopy have been used as practice performance measures., Aim: To evaluate the duration, determinants and outcomes of lagtimes between referral for endoscopic evaluation and colorectal cancer (CRC) diagnosis., Methods: We examined the medical records of 289 patients with CRC and evaluated lagtimes, their potential determinants and their association with CRC stage at diagnosis as well as overall survival., Results: Median lag between referral and CRC diagnosis was 41 days (41.5% > 60 days, 30.1% > 90 days). The only significant predictor of lagtime was the initiating event for referral: abnormal symptom, laboratory test or imaging study was associated with shortest and presence of family history was associated with longest lagtimes respectively. Longer lagtimes were associated with lower mortality risk, but this was completely explained by earlier CRC stage. An analysis restricted to 100 patients referred for abnormal CRC screening tests found no association between duration of lag and CRC stage or mortality., Conclusions: There seems to be no meaningful association between mortality in patients with CRC and lagtimes between referral for colonoscopy and CRC diagnosis for periods up to 2-3 months. On the contrary, longer lagtimes were inversely associated with CRC stage at the time of diagnosis.

Cement-retained, single unit implant supported restorations have become a popular method to treat single tooth edentulous spaces. Occasionally, the clinician is faced with the situation in which the restoration demonstrates mobility. This case report describes the treatment rendered to a patient who presented with a chief complaint of a "loose implant" that had been restored with a cemented PFM crown on a screw retained abutment.

Gastrointestinal stromal tumor (GIST) is a rare, but potentially aggressive tumor. We present an asymptomatic 64-year-old man with an incidental 9-cm GIST that arose in the posterior mediastinum. Wide surgical excision was performed with rotation of an intercostal muscle flap to buttress a surgically created esophageal wall defect. The patient is now free of disease 26 months postoperative. This tumor is defined by the carcinogenic over-expression of KIT-protein, a tyrosine kinase receptor. Accurate diagnosis of gastrointestinal stromal tumor is imperative, as specific medical therapy is now available for potential control of recurrent or metastatic disease.

Previous in vitro data on type I collagen self-assembly into fibrils suggested that the amino acid 776-796 region of the alpha1(I) chain is crucial for fibril formation because it serves as the recognition site for the telopeptide of a docking collagen monomer. We used a natural collagen mutation with a deletion of amino acids 766-801 to confirm the importance of this region for collagen fibril formation. The proband has type III osteogenesis imperfecta and is heterozygous for a COL1A1 IVS 41 A(+4) --> C substitution. The intronic mutation causes splicing of exon 41, confirmed by sequencing of normal and shorter reverse transcriptase-PCR products. Reverse transcriptase-PCR using RNA from proband dermal fibroblasts and clonal cell lines showed the mutant cDNA was about 15% of total alpha1(I) cDNA. The mutant transcript is translated; structurally abnormal alpha chains are demonstrated in the cell layer of proband fibroblasts by SDS-urea-PAGE. The proportion of mutant chains in the secreted procollagen was determined to be 10% by resistance to digestion with MMP-1, since chains lacking exon 41 are missing the vertebral collagenase cleavage site. Secreted proband collagen was used for analysis of kinetics of binding of alpha1(I) C-telopeptide using an optical biosensor. Telopeptide had slower association and faster dissociation from proband than from normal collagen. Purified proband pC-collagen was used to study fibril formation. The presence of the mutant molecules decreases the rate of fibril formation. The fibrils formed in the presence of 10-15% mutant molecules have strikingly increased length compared with normal collagen, but are well organized, as demonstrated by D-periodicity. These results suggest that some collagen molecules containing the mutant chain are incorporated into fibrils and that the absence of the telopeptide binding region from even a small portion of the monomers interferes with fibril growth. Both abnormal fibrils and slower remodeling may contribute to the severe phenotype.in

Inversion of the natural sequence of the B chain of human insulin (HI) from ProB28LysB29 to LysB28ProB29 generates an insulin analogue with reduced tendency to self-associate. Since this substitution increases the homology of insulin to insulin-like growth factor-I (IGF-I), we have examined the affinity of a series of insulin analogues with the general modified structure XaaB28ProB29 HI for binding to both human placental insulin and IGF-I receptors. The XaaB28ProB29 HI series is approximately equipotent to HI in binding to the insulin receptor with the exception of when Xaa = Phe, Trp, Leu, Ile, and Gly (40-60% relative to HI). Substitution with basic residues in the B28 position increased the relative affinity to the IGF-I receptor approximately 1.5-2-fold (ArgB28ProB29 > OrnB28ProB29 = LysB28ProB29). Substitution with acidic residues reduced relative affinity for the IGF-I receptor approximately 2-fold (CyaB28ProB29 = GluB28ProB29 > AspB28ProB29). Combination of AspB10 substitution in conjunction with a modification in the B28-29 position (e.g. AspB10LysB28ProB29 HI) showed an additional 2-fold selective increase in affinity for the IGF-I receptor, suggesting that these two effects are additive. Addition of Arg residues at B31-32, on the backbone of either HI or AspB10 HI, increased affinity for the IGF-I receptor 10 and 28 fold, respectively, compared to HI, confirming the significance of enhanced positive charge at the C-terminal end of the insulin B-chain in increasing selectivity for the IGF-I receptor. This relative increase in IGF-I receptor affinity correlated largely, but not completely, with enhanced growth promoting activity in human mammary epithelial cells. In the case of LysB28ProB29 HI, growth activity correlated with dissociation kinetics from the insulin receptor which were shown to be identical with those of human insulin.

Nearly 1 million Alu elements in human DNA were inserted by an RNA-mediated retroposition-amplification process that clearly decelerated about 30 million years ago. Since then, Alu sequences have proliferated at a lower rate, including within the human genome, in which Alu mobility continues to generate genetic variability. Initially derived from 7SL RNA of the signal recognition particle (SRP), Alu became a dominant retroposon while retaining secondary structures found in 7SL RNA. We previously identified a human Alu RNA-binding protein as a homolog of the 14-kDa Alu-specific protein of SRP and have shown that its expression is associated with accumulation of 3'-processed Alu RNA. Here, we show that in early anthropoids, the gene encoding SRP14 Alu RNA-binding protein was duplicated and that SRP14-homologous sequences currently reside on different human chromosomes. In anthropoids, the active SRP14 gene acquired a GCA trinucleotide repeat in its 3'-coding region that produces SRP14 polypeptides with extended C-terminal tails. A C-->G substitution in this region converted the mouse sequence CCA GCA to GCA GCA in prosimians, which presumably predisposed this locus to GCA expansion in anthropoids and provides a model for other triplet expansions. Moreover, the presence of the trinucleotide repeat in SRP14 DNA and the corresponding C-terminal tail in SRP14 are associated with a significant increase in SRP14 polypeptide and Alu RNA-binding activity. These genetic events occurred during the period in which an acceleration in Alu retroposition was followed by a sharp deceleration, suggesting that Alu repeats coevolved with C-terminal variants of SRP14 in higher primates.

To investigate mechanisms that facilitate transendothelial migration of HIV-infected leukocytes and their interactions with neural tissues early in the disease, we studied peripheral blood from Centers for Disease Control class A patients. Patients' monocytes displayed increased quantities of the adhesion molecules CD11a, CD11b, and very late antigen 4 (VLA-4). Expression of these correlated directly with the numbers of monocytes that migrated through confluent endothelium. These ligands also mediated leukocyte interactions with cultured human neural cell lines. Although patients' cells bound in greater numbers, there was no evidence of target cell injury. To evaluate the direct effect of HIV-1 on monocyte neuroadhesion, we compared infected with uninfected monocytoid (U-937,THP-1) and T lymphoblastoid (MT-4) cell lines. HIV infection increased the neuroadhesiveness of monocytoid lines only. By using lines with more than 95% HIV-infected cells, we demonstrated that HIV-1 gp120 participates with lymphocyte function-associated antigen 1 and VLA-4 to mediate monocyte-neural cell interactions.

Background: Solitary lung nodules in humans caused by the dog parasite Dirofilaria immitis are steadily increasing in number. The organisms can be easily missed in haematoxylin and eosin stained tissue when they are degenerated and pale staining., Methods: The value of Tinopal CBS-X (TCBS-X) and Calcofluor white (CFW), two rapid, inexpensive, simple non-specific fluorescent whitening stains, were assessed in the identification of these worms. Deparaffinised rehydrated tissue slides prepared from the pulmonary nodules were stained for one minute in 1% w/v aqueous solutions of TCBS-X or CFW, counterstained, coverslipped, and viewed with a fluorescent microscope., Results: The stains demonstrated the intact worm and worm fragments in 20 cases of pulmonary dirofilariasis collected from hospitals in Houston. The filariae and fragments of filariae stained bright green while the background tissue stained red, delineating the internal structures of the worm., Conclusions: Dirofilariasis should be included in the differential diagnosis of subpleural masses, and non-specific fluorescent whitening stains can help in the rapid recognition of the fragmented organism in cytological or surgical material.

Mucoepidermoid tumours of the bronchial tree are uncommon neoplasms, which are believed to arise from terminal ducts of the proximal tracheobronchial tree. The first case of a peripheral mucoepidermoid tumour of the lung is reported.