Visual Outcomes Following Surgical Debulking in Exophytic Optic Nerve Sheath Meningiomas

PURPOSE

To report a case of a globular primary optic nerve sheath meningioma managed surgically with improvement in vision and review the literature for outcomes of purely intraorbital exophytic-globular primary optic nerve sheath meningiomas managed surgically.

METHODS

A literature review was conducted using Google Scholar and PubMed with the search terms "primary optic nerve sheath meningioma," "surgery," "exophytic," and "globular." Articles were included if they were available in English. Individual cases from the reviewed articles were included if the tumor was purely intraorbital with a globular or exophytic morphology, was managed with total or subtotal surgical excision, and visual outcomes were reported. Cases were excluded if the tumor extended intracanalicularly or intracranially, tumor morphology was unknown, or surgical management consisted of biopsy, optic nerve sheath decompression, or optic canal decompression rather than tumor debulking.

RESULTS

A total of 28 patients with intraorbital globular-exophytic primary optic nerve sheath meningiomas managed surgically have been reported in the literature. Vision improved in 29% (n = 8/28) and remained stable in 43% (n = 12/28) of patients. Furthermore, patients with good (Snellen notation ≥ 0.5) vision (n = 10) typically retained good vision postoperatively and at follow-up, with 1 patient experiencing a decline to poor (Snellen ≤0.1) vision at the last follow-up (92 months postoperatively). Similarly, patients with fair (Snellen notation >0.1 and <0.5) vision (n = 5) often improved to good vision (n = 3) or stayed at fair vision (n = 1), with 1 declining to poor vision at postoperative hospital discharge.

CONCLUSIONS

Surgical management of exophytic or globular optic nerve meningiomas does not universally lead to vision loss and may be appropriate in select patients.

Investigation of the functional impact of CHED- and FECD4-associated SLC4A11 mutations in human corneal endothelial cells

Mutations in the solute linked carrier family 4 member 11 (SLC4A11) gene are associated with congenital hereditary endothelial dystrophy (CHED) and Fuchs corneal endothelial dystrophy type 4 (FECD4), both characterized by corneal endothelial cell (CEnC) dysfunction and/or cell loss leading to corneal edema and visual impairment. In this study, we characterize the impact of CHED-/FECD4-associated SLC4A11 mutations on CEnC function and SLC4A11 protein localization by generating and comparing human CEnC (hCEnC) lines expressing wild type SLC4A11 (SLC4A11WT) or mutant SLC4A11 harboring CHED-/FECD4-associated SLC4A11 mutations (SLC4A11MU). SLC4A11WT and SLC4A11MU hCEnC lines were generated to express either SLC4A11 variant 2 (V2WT and V2MU) or variant 3 (V3WT and V3MU), the two major variants expressed in ex vivo hCEnC. Functional assays were performed to assess cell barrier, proliferation, viability, migration, and NH3-induced membrane conductance. We demonstrate SLC4A11-/- and SLC4A11MU hCEnC lines exhibited increased migration rates, altered proliferation and decreased cell viability compared to SLC4A11WT hCEnC. Additionally, SLC4A11-/- hCEnC demonstrated decreased cell-substrate adhesion and membrane capacitances compared to SLC4A11WT hCEnC. Induction with 10mM NH4Cl led SLC4A11WT hCEnC to depolarize; conversely, SLC4A11-/- hCEnC hyperpolarized and the majority of SLC4A11MU hCEnC either hyperpolarized or had minimal membrane potential changes following NH4Cl induction. Immunostaining of primary hCEnC and SLC4A11WT hCEnC lines for SLC4A11 demonstrated predominately plasma membrane staining with poor or partial colocalization with mitochondrial marker COX4 within a subset of punctate subcellular structures. Overall, our findings suggest CHED-associated SLC4A11 mutations likely lead to hCEnC dysfunction, and ultimately CHED, by interfering with cell migration, proliferation, viability, membrane conductance, barrier function, and/or cell surface localization of the SLC4A11 protein in hCEnC. Additionally, based on their similar subcellular localization and exhibiting similar cell functional profiles, protein isoforms encoded by SLC4A11 variant 2 and variant 3 likely have highly overlapping functional roles in hCEnC.

Association of Proton Pump Inhibitor Use and Severe Pneumonitis in Stage III Non-Small-Cell Lung Cancer Treated with Primary Chemoradiation and Adjuvant Durvalumab

PURPOSE/OBJECTIVE(S)

Prior studies have suggested gut microbiome changes induced by long-term acid-reducing medication use could modulate immunotherapy efficacy and toxicity. We assessed the relationship between baseline acid-reducing medication use (proton pump inhibitors [PPI] or H2 antagonists [H2A]) on treatment-related toxicity and efficacy in a large cohort of stage III non-small-cell lung cancer (NSCLC) patients treated with or without immunotherapy.

MATERIALS/METHODS

Patients with unresectable stage III NSCLC treated with primary concurrent chemoradiation with or without adjuvant durvalumab from 2015 to 2021 were identified in the Veterans Affairs (VA) system. We defined baseline acid-reducing medication use with VA and non-VA pharmacy records in the year prior to radiation start; the number of prescriptions and the cumulative duration of therapy were quantified. Using multivariable Cox models adjusting for potential baseline confounders and stratified by adjuvant durvalumab use, we estimated the association between PPI or H2A use and subsequent severe pneumonitis, progression-free survival, and overall survival. Pneumonitis was determined and graded by manual chart review.

RESULTS

We included 1994 patients with stage III NSCLC treated with primary chemoradiation, of whom 1005 (50%) received adjuvant durvalumab, 1064 (53%) received any PPI and 1030 (52%) received any H2A. In the overall sample, baseline use of any PPI was associated with increased risk of grade 3-5 pneumonitis (adjusted hazard ratio [aHR] 1.53, 95% CI 1.12-2.10, p = 0.008) and was found to be significant only in durvalumab-treated patients (aHR 1.67, 95% CI 1.10-2.54, p = 0.016), but not for patients treated without durvalumab (aHR 1.34, 95% CI 0.82-2.20, p = 0.2). Higher number of PPI prescriptions were associated with increased risk of severe pneumonitis (aHR 1.38 per 5 prescriptions, 95% CI 1.03-1.85, p = 0.03) and longer duration of PPIs trended toward significance (aHR 1.04 per 90 days, 95% CI 1.00-1.09, p = 0.066). Any PPI use was associated with worse OS in durvalumab-treated patients (aHR 1.30, 95% CI 1.05-1.61, p = 0.016) but not for patients without durvalumab use (aHR 0.99, 95% CI 0.86-1.14, p = 0.9). PPI use had no association with progression-free survival in either cohort. No significant associations between baseline H2A use and pneumonitis, PFS, or OS in either cohort were seen.

CONCLUSION

PPIs, but not H2As, are associated with increased risk of treatment-related pneumonitis and inferior OS in stage III NSCLC patients treated with chemoradiation and immunotherapy. This association was not observed among patients treated with chemoradiation alone. No association was found between PPI use and cancer progression. Further work is warranted to confirm these findings in other immunotherapy-treated cohorts.

Development and evaluation of checklists to support the recruitment of committed hematopoietic stem cell donors

BACKGROUND

Checklists are memory recall tools used across healthcare to improve outcomes. Here, we describe the development and evaluation of checklists to support recruitment of committed allogeneic hematopoietic stem cell donors.

STUDY DESIGN AND METHODS

Checklists were developed with the following objectives: (1) improve best-practice adherence; (2) reduce errors; and (3) support standardization at stem cell drives. Topics included: recruiting needed donors; securing informed consent; maintaining good-documentation practices; and supervising registration and tissue sample collection. Checklists were iteratively revised with input from stakeholders. We evaluated the checklists by examining recruitment outcomes and errors (i.e., preventing registrants from being listed as donors) pre- (11/2011-8/2016) and post- (9/2016-11/2019) implementation by the Canadian donor recruitment organization Stem Cell Club. Quantitative and qualitative methods were employed to analyze recruiters' perspectives on the checklists.

RESULTS

The checklists supported recruitment of donors from needed demographic groups as Stem Cell Club expanded its recruitment effort from 4118 registrants (60% male, 58% non-European) pre-implementation to 10,621 (52% male, 56% non-European) post-implementation. Checklist implementation was associated with a marked reduction in errors (from 13.2% to 1.9%) and a three-fold increase in the match rate of recruited donors (from 0.024% to 0.075%). Qualitative and quantitative analysis of recruiter feedback supported that the checklists' objectives were realized from the recruiter perspective.

DISCUSSION

We developed checklists to support donor recruitment and showed that their implementation was valued by recruiters and associated with both reduced errors and improved donor recruitment outcomes. The checklists are relevant to donor recruitment organizations worldwide.

Infectious keratitis in Vietnam: etiology, organisms, and management at Vietnam National Eye Hospital

AIM

To report the etiologies, risk factors, treatments, and outcomes of infectious keratitis (IK) at a major Vietnamese eye hospital.

METHODS

This is a retrospective review of all cases of IK at Vietnam National Eye Hospital (VNEH) in Hanoi, Vietnam. Medical histories, demographics, clinical features, microbiological results, and treatment outcomes were reviewed.

RESULTS

IK was diagnosed in 1974 eyes of 1952 patients, with ocular trauma being the greatest risk factor for IK (34.2%), frequently resulting from an agriculture-related injury (53.3%). The mean duration between symptom onset and presentation to VNEH was 19.3±14.4d, and 98.7% of patients had been treated with topical antibiotic and/or antifungal agents prior to evaluation at VNEH. Based on smear results of 1706 samples, the most common organisms identified were bacteria (n=1107, 64.9%) and fungi (n=1092, 64.0%), with identification of both bacteria and fungi in 614 (36.0%) eyes. Fifty-five of 374 bacterial cultures (14.7%) and 426 of 838 fungal cultures (50.8%) were positive, with the most commonly cultured pathogens being Pseudomonas aeruginosa, Streptococcus pneumonia, Fusarium spp., and Aspergillus spp. Corneal perforation and descemetocele developed in 391 (19.8%) and 93 (4.7%) eyes, respectively. Medical treatment was successful in resolving IK in 50.4% eyes, while 337 (17.1%) eyes underwent penetrating or anterior lamellar keratoplasty. Evisceration was performed in 7.1% of eyes, most commonly in the setting of fungal keratitis.

CONCLUSION

Ocular trauma is a major risk factor for IK in Vietnam, which is diagnosed in almost 400 patients each year at VNEH. Given this, and as approximately one quarter of the eyes that develop IK require corneal transplantation or evisceration, greater emphasis should be placed on the development of prevention and treatment programs for IK in Vietnam.

Development and evaluation of a community of practice to improve stem cell donor recruitment in Canada

Background and Objectives Communities of practice (CoPs) represent effective models to achieve quality outcomes in health care. We report the development and evaluation of a CoP to improve stem cell donor recruitment in Canada. Materials and Methods In September 2017, we invited national stakeholders in stem cell donor recruitment to participate in a Facebook group and regular e-meetings. E-meetings involved speakers and roundtable discussion on topics related to donor recruitment. The Facebook group facilitated sharing of resources. We evaluated stakeholder perspective of the CoP and the impact on recruitment outcomes. Results As of December 2020, the CoP included 382 members who published 243 posts to the Facebook group about patient/donor stories (40%), resources (27%), updates/questions (21%) and recruitment outcomes (12%). In January 2020, we surveyed 44 CoP participants; the majority felt that the Facebook group (86%) and e-meetings (59%) supported the community, and that the CoP fostered collaboration (82%), improved their donor recruitment knowledge (75%) and practice (77%) and improved their ability to recruit needed donors (64%). The launch of the CoP correlated with improved donor recruitment outcomes. In 2016-2017, CoP participants recruited 2918 registrants (46% male; 55.9% non-Caucasian) compared to 4531 registrants in 2018-2019 (52.9% male; 62.7% non-Caucasian). Members of the CoP developed innovative resources to support recruitment efforts and led national campaigns securing coverage in major media outlets. Conclusion We describe the first CoP in stem cell donor recruitment to be formally evaluated. The CoP model may be adopted by donor recruitment organisations, registries and blood banks worldwide to improve recruitment outcomes. HIGHLIGHTS: • A community of practice (CoP) in stem cell donor recruitment was valued by participants and supported efforts to improve recruitment outcomes. • The CoP model may be adopted by donor recruitment organizations, donor registries, and blood banks worldwide to improve recruitment outcomes.

Corneal ectasia associated with posterior lamellar opacification

BACKGROUND

Concomitant corneal ectasia and posterior lamellar corneal opacification is rare, and the genetic relationship between these two conditions is unclear. We report the genetic and clinical characterization of this phenotype in three unrelated individuals.

MATERIALS AND METHODS

One previously reported affected individual and two unreported, unrelated, affected individuals were recruited for the study. Subjects and unaffected relatives underwent slit lamp examination, refraction, and multi-modal imaging. Saliva samples were obtained from two of the three affected individuals, from which DNA was extracted. Sanger sequencing was performed to identify mutations in genes associated with posterior amorphous corneal dystrophy (PACD), brittle cornea syndrome (BCS), and posterior polymorphous corneal dystrophy (PPCD), while copy number variation (CNV) analysis was used to identify CNV in the PACD locus.

RESULTS

Affected individuals demonstrated bilateral corneal steepening, stromal thinning and lamellar posterior corneal opacification. Corneal topography and tomography revealed conical or globular corneal steepening and decreased thickness. Anterior segment optical coherence tomography demonstrated hyperreflectivity of the posterior stroma in each of the affected individuals. Genetic testing did not detect a heterozygous deletion involving the PACD locus on chromosome 12 or a pathogenic mutation in the genes associated with BCS or PPCD.

CONCLUSIONS

Corneal ectasia may be associated with posterior lamellar stromal opacification that appears consistent with PACD. However, genetic testing for PACD as well as BCS and PPCD in affected individuals fails to reveal pathogenic deletions or mutations, indicating that other genetic factors are involved.

Single horizontal rectus muscle vertical augmented transposition with posterior fixation suture in management of monocular elevation deficiency

We describe successful management of three cases of acquired monocular elevation deficiency (MED) with superior transposition of the lateral rectus augmented with a posterior fixation suture with or without simultaneous inferior rectus muscle weakening. In each case, the lateral rectus muscle was transposed superiorly to the superior rectus muscle along the spiral of Tillaux, with maintained distance between the original lateral rectus muscle poles and the limbus. Augmentation was achieved with a posterior fixation suture 8 mm posterior to the muscles' insertion. At the time of lateral rectus transposition, simultaneous inferior rectus recession by 5.5 mm was performed in case 1 whereas simultaneous botulinum toxin injection was performed in case 3. With regards to all three cases, the mean age was 32 years [10-46 years] and the mean follow-up period was 10 months. The mean hypotropia was reduced from 35 prism diopters (PD) (range: 20 to 60 PD) to 4.67 PD (range: 0 to 14 PD) with a mean correction of 32.57 ± 9.34 PD after 9 months. In our experience, full-tendon-width transposition of the lateral rectus to the superior rectus with posterior fixation suture corrects primary position hypotropia in MED and does not always require simultaneous inferior rectus recession. When transposing the lateral rectus muscle along the spiral of Tillaux, the measured distance of the original muscle insertion point to the limbus must be maintained in order to prevent recession of the muscle.

Comparison of early visual outcomes after low-energy SMILE, high-energy SMILE, and LASIK for myopia and myopic astigmatism in the United States

PURPOSE

To compare uncorrected distance visual acuities (UDVAs) and induced higher-order aberrations (HOAs) in the early postoperative period between low-energy (LE) small-incision lenticule extraction (SMILE), high-energy (HE) SMILE, and femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK) procedures.

SETTING

University based refractive surgery center.

STUDY DESIGN

Retrospective cohort study.

METHODS

Records of patients who underwent SMILE or FS-LASIK were retrospectively reviewed. SMILE patients were separated into 2 groups: HE settings (125 nJ, 3.0 μm spot spacing) and LE settings (125-130 nJ, 4.5 μm spot spacing). UDVA was measured at postoperative day (POD) 1. Corneal HOAs and UDVA were measured at postoperative month (POM) 1. Induced spherical aberration, vertical coma, horizontal coma, total coma, and total HOAs were calculated.

RESULTS

The study included 147 eyes of 106 patients, 49 in each group. For SMILE patients, the difference in mean UDVA at POD1 was highly statistically significant in favor of the LE group (-0.003 vs 0.141, P < .0001). No significant difference in mean UDVA at POD1 was noted between the LE group and FS-LASIK group (-0.003 vs -0.011, P = .498). Induced change in spherical aberration was less in LE SMILE than that in FS-LASIK (0.136 vs 0.186 μm, P = .02) at POM1. No significant differences in POM1 mean UDVA (-0.033 vs -0.036) or induced change in all other HOAs were noted between LE SMILE and FS-LASIK.

CONCLUSIONS

LE settings were associated with significantly improved POD1 UDVA. POD1 and POM1 UDVA were comparable with those of FS-LASIK. Spherical aberration induction was less with LE SMILE than that with FS-LASIK, whereas all other induced HOAs were comparable with FS-LASIK.

Identification of A Novel TGFBI Gene Mutation (p.Serine524Cystine) Associated with Late Onset Recurrent Epithelial Erosions and Bowman Layer Opacities

BACKGROUND

Most transforming growth factor beta-induced (TGFBI) corneal dystrophies are associated with a characteristic phenotype, clinical course, and a conserved mutation in the TGFBI gene. However, we report a novel TGFBI missense mutation associated with a late-onset, variant Bowman layer dystrophy.

METHODS

Participants underwent slit-lamp examination and multimodal imaging. Polymerase chain reaction amplification and Sanger sequencing were performed on saliva-derived genomic DNA to screen TGFBI exons 4 and 12 as well as COL17A1 exon 46. PolyPhen-2 and SIFT were used to predict the functional impact of any identified variants.

RESULTS

A 56-year-old Thai woman reported a four-year history of decreased vision and intermittent eye irritation, suggestive of recurrent epithelial erosions, in both eyes. Slit-lamp exam revealed bilateral, irregular, limbal-sparing Bowman layer opacities, which were also noted on anterior segment optical coherence tomography. Phototherapeutic keratectomy was performed in the right eye, improving the best-corrected visual acuity from 20/50 to 20/30. Sequencing of the TGFBI gene revealed a novel heterozygous, missense mutation in exon 12 (c.1571 C > G; p.Ser524Cys), which was present in an affected son and absent in an unaffected son, and was predicted to be damaging by PolyPhen-2 and SIFT. The patient was diagnosed with a variant Bowman layer dystrophy given the late onset of an atypical phenotype and the identification of a novel TGFBI mutation.

CONCLUSIONS

A novel TGFBI missense mutation is associated with a late-onset Bowman layer dystrophy. Given the atypical clinical appearance and course, molecular genetic analysis was utilized to establish a definitive diagnosis.

Trans-stromal epithelial cyst after multiple lamellar keratoplasties - Case report and review of literature

Design

Single Observational Case Report.

Setting

A 67-year-old male of Persian descent had a complex systemic and ocular history prior to a right penetrating keratoplasty (PK) reported here. The clinical diagnoses leading to the PK included Cogan's syndrome, chronic uveitis, secondary glaucoma, and corneal stromal scarring, presumed secondary to a corneal ulcer diagnosed on the second visit to our clinic. The specimen described here had been in place for 11 months and 17 days after the third failed Descemet stripping endothelial keratoplasty (DSEK). Visual acuities had ranged from 20/100 to 20/400 in both eyes. Visual acuity in the right eye just before surgery was 20/400. Intraocular pressures were 22 mmHg in both eyes with functioning Ahmed glaucoma shunts. The stromal cyst was not suspected preoperatively and no clinical imaging was performed.

Study Methods

Histopathology including serial sections and immunohistochemistry.

Results

Histologic study demonstrated a trans-stromal corneal epithelial cyst without goblet cells that extended through a 500 μm gap in the donor tissue surface and edge.

Conclusions

This large stromal cyst was an unusual complication of serial posterior lamellar keratoplasties and we postulate that multiple prior posterior lamellar grafts may have been a risk factor for this complication. Anterior segment imaging with either anterior segment optical coherence tomography or high-resolution ultrasound would likely have detected this stromal cyst.

Let-7 derived from endometrial extracellular vesicles is an important inducer of embryonic diapause in mice

Embryonic diapause is a maternally controlled phenomenon. The molecule controlling the onset of the phenomenon is unknown. We demonstrated that overexpression of microRNA let-7a or incubation with let-7g-enriched extracellular vesicles from endometrial epithelial cells prolonged the in vitro survival of mouse blastocysts, which developed into live pups after having been transferred to foster mothers. Similar to in vivo dormant blastocysts, let-7-induced dormant blastocysts exhibited low level of proliferation, apoptosis, and nutrient metabolism. Let-7 suppressed c-myc/mTORC1 and mTORC2 signaling to induce embryonic diapause. It also inhibited ODC1 expression reducing biosynthesis of polyamines, which are known to reactivate dormant embryos. Furthermore, the overexpression of let-7 blocked trophoblast differentiation and implantation potential of human embryo surrogates, and prolonged survival of human blastocysts in vitro, supporting the idea that embryonic diapause was an evolutionary conserved phenomenon. In conclusion, let-7 is the main factor inducing embryonic diapause.

Telehealth in Pediatric Heart Transplant Patients: Exercise, Nutrition, and Parental Imaging

Telehealth is a promising new tool in medicine that has changed the landscape of medical care. The benefits of telehealth technology are immense, including improved access to care and potential savings in monetary and opportunity costs. Current challenges of incorporating telehealth services into regular clinical care include licensure and regulatory barriers, difficulty obtaining insurance reimbursements, and high costs of setting up successful telehealth infrastructures. These challenges threaten telehealth's future scalability and expansion to reach all patients in need.

Current Status of Ophthalmology Residency Training in China: The Experience From Well-Structured Centers Around the Country

Chinese ophthalmology residency training is continuously evolving with an emphasis on standardization. In this article, we assess the current status of ophthalmology residency training in China compared with that in the United States through analysis of literature review and onsite data collection. We comprehensively review various aspects of the residency training structure in China, including accreditation, resident selection, clinical and surgical curricula, research requirements, and evaluation. Our report demonstrates significant regional differences among training programs due to the lack of a national standard, resulting in varying competencies of graduating Chinese ophthalmology residents. The Chinese ophthalmology community is determined to improve the standardization process and quality of training for their ophthalmologists, an important goal that will facilitate international fellowship studies, exchange scholars, and research collaboration.

Healthy Hearts via Live Videoconferencing: An Exercise and Diet Intervention in Pediatric Heart Transplant Recipients

Background

Pediatric heart transplant recipients have high‐risk cardiovascular profiles that can affect their long‐term outcomes; however, promoting exercise and healthy diet has not been a major focus in the field. The objective of this study was to test the feasibility and impact of a supervised exercise and diet intervention delivered via live videoconferencing in this population.

Methods and Results

Patients 8 to 19 years of age at least 1 year post heart transplantation were enrolled. The 12‐ to 16‐week intervention phase included live video–supervised exercise (×3/week) and nutrition (×1/week) sessions. The 12‐ to 16‐week maintenance phase included ×1/week live video–supervised exercise and nutrition sessions and ×2/week self‐directed exercise sessions. Cardiac, vascular, nutritional, and functional health indices were obtained at baseline, after intervention, and after maintenance. Fourteen patients (median age, 15.2; interquartile range, 14.3–16.7 years) at a median of 3.3 (interquartile range, 1.5–9.7) years after heart transplant completed the intervention. Patients attended 89.6±11% of exercise and 88.4±10% of nutrition sessions during the intervention and 93.4±11% of exercise and 92.3±11% of nutrition sessions during maintenance. After intervention, body mass index percentile (median, −27%; P=0.02), endothelial function (median, +0.29; P=0.04), maximum oxygen consumption (median, +2 mL/kg per minute; P=0.002). Functional Movement Screening total score (median, +2.5; P=0.002) and daily consumption of saturated fat (median, −6 g; P=0.02) improved significantly. After maintenance, improvements in maximum oxygen consumption (median, +3.2 mL/kg per minute; P=0.02) and Functional Movement Screening total score (median, +5; P=0.002) were sustained.

Conclusions

In pediatric heart transplant recipients, a live video–supervised exercise and diet intervention is feasible. Our results demonstrate excellent adherence with significant improvements in cardiovascular and functional health.

Clinical Trial Registration

URL: http://www.clinicaltrials.gov. Unique identifier: NCT02519946.

Vascular Health of Children Conceived via In Vitro Fertilization

OBJECTIVE

To evaluate whether in vitro fertilization (IVF) has an effect on the cardiovascular health of offspring.

STUDY DESIGN

This was a cross-sectional pilot study. We performed vascular health assessment for 17 children aged 10-14 years who were conceived via IVF with autologous oocytes at Stanford University. Carotid artery ultrasound evaluated intima-media thickness and stiffness, carotid-femoral pulse wave velocity determined segmental arterial stiffness, and endothelial pulse amplitude testing assessed endothelial function. We compared IVF offspring with control adolescents assessed in the same laboratory, with all comparisons adjusted for age, sex, and race/ethnicity.

RESULTS

All participants had normal body mass index and blood pressure. Compared with controls, IVF children had thicker common carotid artery intima-media thickness (0.44 ± 0.03 mm vs 0.38 ± 0.03 mm; P < .01), higher elastic modulus (395.29 ± 185.33 mm Hg vs 242.79 ± 37.69 mm Hg; P = .01), higher βstiffness (2.65 ± 0.38 vs 2.28 ± 0.23; P < .01), and higher peak velocity (142.29 ± 31.62 cm/s vs 117.71 ± 32.69 cm/s; P = .04). The mean endothelial pulse amplitude testing reactive hyperemia index was not significantly different between IVF and controls. The mean pulse wave velocity was 4.69 ± 0.51 m/s compared with the controls 4.60 ± 0.57 m/s (P = .11), with 8 (47%) having abnormal values.

CONCLUSION

In an assessment of endothelial function and arterial properties of children conceived via IVF, we found that children conceived via IVF seem to have evidence of abnormal vascular health. Further studies with larger sample size and long-term follow-up are warranted.

Severe Acquired Restrictive Strabismus Fixus in Patients with Trisomy 21

Acquired strabismus fixus is a rare form of severe esotropia described most frequently in patients with high axial myopia and infrequently associated with other conditions. Refractive errors, cataracts, and ocular motility disorders are common in patients with trisomy 21. We report two unusual cases of patients with trisomy 21 who developed severe acquired restrictive strabismus fixus. Both patients were successfully treated with medial rectus recession followed by lateral rectus and superior rectus myopexy combined with additional medial rectus weakening, including free tenotomy in one case.

Healthy hearts in pediatric heart transplant patients with an exercise and diet intervention via live video conferencing-Design and rationale

BACKGROUND

Pediatric heart transplant (PedHtx) patients have increased cardiovascular risk profiles that affect their long-term outcomes and quality of life. We designed a 12- to 16-week diet and exercise intervention delivered via live video conferencing to improve cardiovascular health. Our methodology and baseline assessment of the first 13 enrolled patients are reported.

METHODS

Inclusion criteria are as follows: (a) 8-19 years old; (b) heart transplant >12 months; (c) ability to fast overnight; (d) cardiac clearance by cardiologist; and (e) presence of an adult at home during exercise sessions for patients <14 years old. Exclusion criteria are as follows: (a) acute illness; (b) latex allergy; (c) transplant rejection <3 months ago; and (d) multi-organ transplantation. The intervention consists of one diet and three exercise sessions weekly via live video conferencing. Study visits are conducted at baseline, intervention completion, and end of maintenance period.

RESULTS

A total of 13 participants (15.2 [2.3] years) have been enrolled. Median percent-predicted VO₂ max was 56.8 [20.7]% (10 patients <70%). Ten patients had abnormal endothelial function (reactive hyperemia index <1.9; 1.4 [0.325]) and 11 patients had stiff arteries (pulse wave velocity ≧5.5 m/s for 15-19 years, ≧4.5 m/s for 8-14 years; 5.6 [0.7] m/s). Patients had suboptimal diets (saturated fat: 22.7 [23.8] g/d, sodium: 2771 [1557] mg/d) and were sedentary at a median of 67.5 [13.8]% of their time.

CONCLUSIONS

Baseline assessment confirms that PedHtx patients have abnormal cardiac, vascular, and functional health indices, poor dietary habits, and are sedentary. These results support the rationale to test the feasibility and impact of a non-pharmacologic lifestyle intervention in this patient population.

Biochemical and Skeletal Outcomes of Parathyroidectomy for Normocalcemic (Incipient) Primary Hyperparathyroidism

BACKGROUND

Normocalcemic (incipient) primary hyperparathyroidism (PHPT) is characterized by inappropriately elevated parathyroid hormone (PTH) levels in the setting of normal serum calcium. The biochemical and skeletal outcomes after parathyroidectomy for normocalcemic PHPT are not well-described.

METHODS

All patients who underwent parathyroidectomy for normocalcemic PHPT at a single institution were retrospectively reviewed (2006-2016). Pre- and postoperative calcium, PTH, and bone mineral density (BMD) were compared between patients with normalized versus persistently elevated PTH levels > 6 months after parathyroidectomy. Multivariable Cox regression was used to identify risk factors associated with persistently elevated PTH levels after parathyroidectomy.

RESULT

Parathyroidectomy was performed in 71 patients with normocalcemic PHPT, of whom 38 (53.5%) had multi-gland disease. No patients became hypercalcemic, with a median follow-up of 23.1 months. Persistently elevated PTH levels were noted in 33 (46.5%) patients. In multivariable analysis, preoperative PTH > 100 pg/mL was associated with persistently elevated PTH levels after parathyroidectomy. In 38 patients with available pre- and postoperative BMD measurements, the mean preoperative BMD improved + 5.6% (p < 0.01) in patients with normalized PTH, while no significant change was observed in patients with persistently elevated PTH levels (- 2.2%, p = 0.47).

CONCLUSIONS

Elevated PTH levels are common after parathyroidectomy for normocalcemic PHPT. Improvements in BMD may be predicated on long-term normalized PTH levels following surgery.

Rev7 and 53BP1/Crb2 prevent RecQ helicase-dependent hyper-resection of DNA double-strand breaks

Poly(ADP ribose) polymerase inhibitors (PARPi) target cancer cells deficient in homology-directed repair of DNA double-strand breaks (DSBs). In preclinical models, PARPi resistance is tied to altered nucleolytic processing (resection) at the 5’ ends of a DSB. For example, loss of either 53BP1 or Rev7/MAD2L2/FANCV derepresses resection to drive PARPi resistance, although the mechanisms are poorly understood. Long-range resection can be catalyzed by two machineries: the exonuclease Exo1, or the combination of a RecQ helicase and Dna2. Here, we develop a single-cell microscopy assay that allows the distinct phases and machineries of resection to be interrogated simultaneously in living S. pombe cells. Using this assay, we find that the 53BP1 orthologue and Rev7 specifically repress long-range resection through the RecQ helicase-dependent pathway, thereby preventing hyper-resection. These results suggest that ‘rewiring’ of BRCA1-deficient cells to employ an Exo1-independent hyper-resection pathway is a driver of PARPi resistance.

Healthy cells can typically repair damage to their DNA with high accuracy, keeping their genetic code intact. In contrast, cancer cells often lose this ability. Inaccurate repair leads to more frequent DNA mutations, which can make a tumor more aggressive. However, DNA repair-deficient tumors can be targeted with cancer therapies, such as PARP inhibitors, which kill cells that do not have working DNA repair mechanisms. PARP inhibitors show great promise clinically, but unfortunately some tumor cells can become resistant to these treatments over time. Recent work has shown that resistance to PARP inhibitors is often caused by further alternations to DNA repair machineries.

Being able to visualize DNA repair in living cells is crucial to understanding this process and to find ways to improve cancer treatments. Previous studies have used repetitive DNA sequences called Lac operators (LacO) to visualize the dynamic behavior of DNA in live cells. Leland et al. have now adapted this system to watch individual DNA repair events in living yeast cells under the microscope. Their experiments reveal that when cells lose a single protein called Rev7, an early phase of DNA repair becomes hyperactive. Leland et al. traced the cause of this hyperactivity to an enzyme in the RecQ helicase family.

A RecQ helicase becoming hyperactive in cells lacking Rev7 could explain how some cancer cells become resistant to PARP inhibitor treatments. This information could help fine-tune future approaches to treating cancer. For example, using an inhibitor of RecQ helicase alongside PARP inhibitors may help block this type of resistance from developing in the first place. As well as potentially paving the way for better cancer treatments, this method of visualization could improve scientists’ understanding of the basic processes of DNA repair.

Recent Pregnancy Is Not Associated with High-Risk Pathological Features of Well-Differentiated Thyroid Cancer

BACKGROUND

Thyroid cancer is commonly diagnosed in the first postpartum year, supporting the theory that high levels of estrogen may stimulate progression of hormone-mediated thyroid cancer. The aim of this study was to assess the effect of recent pregnancy on histopathologic disease characteristics of well-differentiated thyroid cancer (WDTC).

METHODS

Cases of WDTC (1999-2012) were identified from the California Cancer Registry and linked to data from the Office of Statewide Health Planning and Development. Using a matched control design, recently pregnant women (pregnancy up to five years before and nine months after a thyroid cancer diagnosis) were compared with non-pregnant controls matched by age and race/ethnicity. The main outcome measures were histopathologic tumor characteristics (tumor size, extrathyroidal extension, and nodal metastases), disease status at last follow-up, and five-year disease-specific survival.

RESULTS

The study sample of 1204 women (M_age ± standard deviation = 30.9 ± 5.5 years; 46.5% Caucasian and 40.0% Hispanic) included 301 recently pregnant women matched against 903 non-pregnant controls. Comparing recently pregnant versus non-pregnant women, no significant differences were observed with respect to tumor size (M = 2.2 ± 1.6 vs. 2.3 ± 3.9 cm; p = 0.39), extrathyroidal extension (12.0% vs. 14.1%; p = 0.46), stage at diagnosis (localized disease: 67.4% vs. 62.8%; regional metastases: 30.6% vs. 33.4%; distant metastases: 2.0% vs. 3.8%; p = 0.17), disease status at last follow-up (free of tumor vs. not free of tumor; p = 0.48), and five-year disease-specific survival (99.5% vs. 99.5%). In multivariate analyses, after controlling for patient age and ethnicity, recent pregnancy was not a significant predictor of tumor size, extrathyroidal extension, nodal metastases, or distant metastases.

CONCLUSIONS

In this cohort, recent pregnancy was not associated with high-risk pathological features of differentiated thyroid cancer. These findings provide reassurance with regards to the concern that pregnancy may act as a potential stimulus for thyroid cancer growth.

Microstructural remodeling of articular cartilage following defect repair by osteochondral autograft transfer

OBJECTIVE

To assess collagen network alterations occurring with flow and other abnormalities of articular cartilage at medial femoral condyle (MFC) sites repaired with osteochondral autograft (OATS) after 6 and 12 months, using quantitative polarized light microscopy (qPLM) and other histopathological methods.

DESIGN

The collagen network structure of articular cartilage of OATS-repaired defects and non-operated contralateral control sites were compared by qPLM analysis of parallelism index (PI), orientation angle (α) relative to the local tissue axes, and retardance (Γ) as a function of depth. qPLM parameter maps were also compared to ICRS and Modified O'Driscoll grades, and cell and matrix sub-scores, for sections stained with H&E and Safranin-O, and for Collagen-I and II.

RESULTS

Relative to non-operated normal cartilage, OATS-repaired regions exhibited structural deterioration, with low PI and more horizontal α, and unique structural alteration in adjacent host cartilage: more aligned superficial zone, and reoriented deep zone lateral to the graft, and matrix disorganization in cartilage overhanging the graft. Shifts in α and PI from normal site-specific values were correlated with histochemical abnormalities and co-localized with changes in cell organization/orientation, cloning, or loss, indicative of cartilage flow, remodeling, and deterioration, respectively.

CONCLUSIONS

qPLM reveals a number of unique localized alterations of the collagen network in both adjacent host and implanted cartilage in OATS-repaired defects, associated with abnormal chondrocyte organization. These alterations are consistent with mechanobiological processes and the direction and magnitude of cartilage strain.

Abstract P6-07-11: Is the prognosis of lymphotropic invasive micropapillary carcinoma worse than invasive ductal carcinoma?: A population-based study of 645 patients

Purpose: Invasive micropapillary carcinoma (IMPC) is an uncommon distinct variant of breast carcinoma and is associated with an increased risk for regional lymph node metastases. Therefore, IMPC is considered to have an unfavorable prognosis when compared to invasive ductal carcinoma (IDC). The prognostic factors for IMPC are not well characterized due to the relative scarcity of cases reported in the literature.

Methods: We analyzed the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) database to evaluate prognostic factors of a population of 645 breast IMPC patients and 300,060 breast IDC patients reported between 2001 and 2008. Using univariate and multivariate analyses, hazard ratios (HR) were calculated for disease-specific (DSS) and overall survival (OS) for these patients using parameters such as patient age at diagnosis, histological grade, ER status, PR status, tumor size, and degree of lymph node positivity. Subset analysis of high grade, lymph node-positive patients was performed to compare DSS and OS between IMPC and IDC.

Results: The 5-year DSS and OS for IMPC patients were 92.1% and 84.6% compared to 5-year DSS and OS of 88.5% and 80.2% for IDC patients. At presentation, TNM staging of IMPC cases was similar to IDC except for a higher percentage of LN metastases (52.4% in IMPC vs. 34.7% in IDC). Of those with known estrogen receptor (ER) status, 84.2% of IMPC cases were ER-positive, which was associated with better DSS (Hazard Ratio (HR) 0.36, p &lt; 0.002) and OS (HR 0.62, p = 0.072). Patients with four or more positive lymph nodes had worse DSS (HR 7.1, p &lt; 0.0001) and OS (HR 3.2, p &lt; 0.0001) than node-negative patients, but those with one to three positive lymph nodes had similar DSS (HR 1.04, p = 0.96) and OS (HR 0.99, p = 0.97) as node-negative patients. In the subset of patients with high grade, node-positive breast carcinoma, patients with micropapillary histology had better DSS (p &lt; 0.03) and a trend towards better OS (p = 0.12) than high grade, node-positive invasive ductal carcinoma. This subset of IMPC patients also had a higher percentage of ER-positive tumors (77%) compared to IDC patients (56%).

Conclusions: While IMPC has a high propensity for lymph node metastasis, it has a disease-specific and overall prognosis that compares favorably to IDC. The higher percentage of hormone-receptor positivity may account for this survival advantage, even in high grade, node-positive disease. Therefore, estrogen-receptor-negativity or having four or more positive lymph nodes at presentation may potentially serve as prognostic markers for IMPC patients. In this study population, patients with one to three positive lymph nodes have DSS and OS similar to node-negative patients. Additional clinical studies are warranted to further investigate this observation. This is the largest study of IMPC to date, and these findings help our understanding of this uncommon histological variant of breast cancer.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P6-07-11.

Abstract P2-06-09: Mucin4 Is Associated with the Loss of Estrogen-Receptor-α in Breast Cancer

Data suggests that breast carcinomas that overexpress the HER2 oncoprotein are more resistant to endocrine treatments such as tamoxifen (Tam) or estrogen deprivation (ED) via aromatase inhibitors. To investigate possible mechanisms of endocrine resistance in vivo, we performed a gene microarray analysis on estrogen receptor-(ER)+, HER2-overexpressing xenograft tumors that are de novo resistant to tamoxifen treatment and acquire resistance to ED therapy. A large number of genes were upregulated, including several members of the mucin family of genes. This corroborated our finding from histological staining of the resistant tumors that indicated striking increases of mucin vacuoles when compared to sensitive tumors. These vacuoles were located mostly intracellularly and stained positive for mucins with mucicarmine. We were particularly interested in one particular mucin, mucin4 (MUC4) because previous studies have suggested its role in stabilizing and enhancing HER2 signaling. Quantitative realtime PCR confirmed the microarray results and showed that there was an approximately 156-fold increase in MUC4 transcript between the ED-sensitive and ED-resistant tumors, with a 65-fold increase between the early Tam and late Tam-resistant tumors. Immunohistochemistry confirmed that this upregulation in these two treatment groups was present also at the protein level. Furthermore, western blot analysis of these tumors demonstrated that resistant tumors have downregulation of ER protein and its downstream effectors with corresponding increase in total HER2 protein levels. These tumors have seemingly shifted away from the ER pathway to signaling via the growth factor signaling pathway. Preliminary experiments where MUC4 protein was stably overexpressed in ER+, HER2-overexpressing cells model these results in vitro with a downregulation of ER protein and downstream effectors, showing that ER expression and activity are affected. Furthermore, immunohistochemical analysis of 73 primary human invasive breast carcinomas suggests that MUC4 is associated with estrogen-receptor negative tumors (P=0.05). This clinical data validates the preclinical studies for investigating a possible mechanism for the loss of ER, and suggest MUC4 as an inviting biomarker for endocrine treatment and a potential therapeutic target for endocrine resistant breast cancer.

Crosstabulation of MUC4 and ER

Serial analysis of gene expression in the southern cattle tick following acaricide treatment of larvae from organophosphate resistant and susceptible strains

Organophosphate resistant and susceptible tick larvae from laboratory strains of the southern cattle tick, Rhipicephalus (Boophilus) microplus were exposed to low doses of the organophosphate (OP) acaricide, coumaphos. Serial analysis of gene expression (SAGE) was used to analyse differential gene expression in response to OP treatment and to compare the responses of OP-treated and -untreated resistant and susceptible tick larvae. An R. microplus Gene Index was used as an EST database to identify genes which corresponded to SAGE tags whose abundance changed in response to acaricide exposure. Relative quantitative RT-PCR was used to confirm the differential expression results from the SAGE experiments. Of particular interest is a SAGE tag which corresponds to a cytochrome P450-like EST in the Gene Index which was more abundant in untreated OP resistant larvae compared to untreated OP susceptible larvae. This SAGE tag was also more abundant in OP resistant larvae treated with OP compared to OP susceptible larvae treated with OP.

Simultaneously evaluating the effects of one-week fluticasone propionate inhalation therapy on lung ventilation and permeability in children with asthma

This study evaluated the effects of fluticasone propionate inhalation therapy on lung ventilation and alveolar permeability by quantitative Tc-99m DTPA radioaerosol inhalation lung scintigraphy in 15 children with asthma. Lung ventilation was evaluated as the distribution percentage (D%) of Tc-99m DTPA radioaerosols in the central, intermediate and peripheral regions of the right lung. Alveolar permeability was measured by the rate of Tc-99m DTPA radioaerosol clearance curve from the peripheral alveoli of the right lung and represented as slope. The D% and slopes were calculated before and after one-week inhalation therapy (100 microg fluticasone propionate two times daily for one-week) to evaluate the effects of inhalation therapy on lung ventilation and alveolar permeability. The preliminary results revealed statistically significantly improved lung ventilation but no significant change of alveolar permeability in the right lung after one-week fluticasone propionate inhalation therapy in children with asthma. We suggest that the widely available and noninvasive Tc-99m DTPA radioaerosol inhalation lung scintigraphy can simultaneously evaluate lung ventilation and alveolar permeability in one study and should contribute to any disorder involving both alveoli and airways.

The effects of one-week fluticasone propionate inhalation therapy for Tc-99m DTPA radioaerosol distribution in asthma of children: a preliminary report

This study evaluated the effects of fluticasone propionate inhalation therapy for the distribution pattern of Tc-99m DTPA radioaerosols in 10 children with asthma. The homogeneous degree of depositing Tc-99m DTPA radioaerosol was evaluated using a modified standard score system over the bilateral lungs. The baseline scores were calculated from Tc-99m DTPA radioaerosol inhalation lung scintigraphy before inhalation therapy (100 microg fluticasone propionate two times daily for one week), and the scores were recalculated after inhalation therapy to evaluate the effects of one-week of fluticasone propionate inhalation therapy for Tc-99m DTPA radioaerosol distribution patterns. After one week of fluticasone propionate inhalation therapy, the scores were decreased in all of the 10 children, which may mean that the bronchial constriction degree due to asthma is decreased. In addition, there was a significantly statistical difference in the scores before and after one-week fluticasone propionate inhalation therapy (p < 0.05). In conclusion, one-week fluticasone propionate inhalation therapy could significantly improve the bronchial constriction due to asthma in children based on the evidence of Tc-99m DTPA radioaerosol inhalation lung scintigraphic findings.

Acetate synthesis from H2/CO2 in simulated and actual landfill samples

To investigate the characteristics of biological decomposition in a municipal solid waste landfill, laboratory simulated samples and full-scale actual samples excavated from landfills in Taiwan were used. Nitrogen gas was produced continuously in the simulated samples. Although nitrate or nitrite could not be detected in the leachate, this did not indicate that nitrate or nitrite was not available in the solid waste. Landfills both produce and consume H2 under anaerobic conditions. In the suspension experiment, where H2/CO2 were used as substrate, significant acetate concentration accumulated concomitantly along with hydrogen consumption. Relatively low production of methane was observed in both the simulated sample and actual samples. Collectively, acetate synthesis was the dominant reaction in the simulated sample and actual samples for hydrogen consumption. This study was the first paper reporting that the homoacetogenesis was the significant process in the landfill for hydrogen utilization, which was validated by the consumption of 4.01-5.43 moles of hydrogen per mole acetate formed. The significant acetate accumulation indicated that the homoacetogens outcompeted the hydrogentrophic methanogens in the landfill samples. Metabolically versatile homoacetogens can use many more substrates simultaneously than their competitor which is bound only to a very few substrates. Themetabolic versatility of homoacetogens could be the main reason for their success in the landfill

Molecular cloning and nucleotide sequence of a new P450 gene, CYP319A1, from the cattle tick, Boophilus microplus

We have isolated and sequenced a novel P450 gene (CYP319A1) from the cattle tick, Boophilus microplus. The CYP319A1 cDNA encodes a protein of 531 amino acids with an estimated molecular weight of 60.9k. It contains all highly conserved motifs characteristic of P450 enzymes. Comparison of deduced amino acid sequence with other CYP members shows that the CYP319A1 is more closely related to CYP4 family, but its overall identity to the CYP4 family is less than 40%. Therefore, it was assigned to a new P450 family by the P450 nomenclature committee. A pseudogene which shares high homology with the CYP319A1 was identified. Analysis of genomic sequence of the pseudogene indicated that the pseudogene contains two additional DNA inserts in the coding region, which disrupt the open reading frame. RT-PCR analysis showed that CYP319A1 is expressed in both susceptible and acaricide-resistant ticks.

Non-painful and painful surface and intramuscular electrical stimulation at the thenar and hypothenar sites: differential cerebral dynamics of early to late latency SEPs

Little is known about somatosensory evoked potentials (SEPs) from muscle stimulation compared to that from skin stimulation. The current study examined this issue in the full SEP spectrum (0-440 ms). The aims of the study were to (1) establish the dynamics of early to late latency SEPs from intramuscular stimulation in contrast to surface stimulation, (2) compare the effect of non-painful and painful stimuli on SEP latencies and amplitudes of the two methods, and (3) investigate to which extent these results can be shared between the median nerve innervated thenar site and ulnar nerve innervated hypothenar site. Stimuli were delivered (2 Hz) at a non-painful and a painful intensity above or within the thenar and hypothenar muscles of the hand. Maximas of the SEPs were extracted by a combination of global field power and visual inspection of the topographies. Amplitudes and latencies of the maximas were analysed by a two-way ANOVA with repeated measures. In the early phase (0-50 ms) the topographic patterns showed different dynamics between surface and intramuscular stimulation and in the late phase (100- 440 ms) prolonged latencies were found for intramuscular stimulation. Apart from this, similar topographic patterns and time sequences were obtained. Significant higher SEP amplitudes for most of the isolated components (C4'/P25, Fz/N35, C4'/P45, Fc2/N65, P4/P90, T4/N137, F3/P150, Cz/P240-P270) were found with surface stimulation compared to intramuscular stimulation. In contrast to surface stimulation, intramuscular stimulation at a stimulation frequency of 2 Hz did not result in a differentiation in amplitude for any of the isolated components. These results indicate differences in the early and late processing of sensory input from skin and muscle.

A mixed modality paradigm for recording somatosensory and auditory P50 gating

Significant somatosensory evoked potential (SEP) P50 gating has previously been found in young healthy men by the use of identical paired stimuli. In this study, the exploration of the gating paradigm was extended with the addition of a mixed modality paradigm where three different pairs of identical stimuli (clicks, right median nerve electric stimulations and proprioceptive stimuli of changing load on a handheld weight) were presented over a 12-s cycle. In both modalities repeated measures analyses of variance demonstrated no effect of paradigm. This mixed-modality recording paradigm could be used in further experiments to examine gating deficits across modalities.

Contact heat evoked potentials as a valid means to study nociceptive pathways in human subjects

Contact heat evoked potentials (CHEPs) have been difficult to elicit due to slow temperature rise times. A recently developed heat-foil technology was used to elicit pain and CHEPs. Two groups of subjects were separately stimulated at the left arm with contact heat via one fast-acting (70 degrees C/s) heat-foil thermode. A set of CHEPs was recorded, each at three subjective intensities: warm; slight; and moderate pain. In CHEPs, the 3D topography exhibited four components: T3-T4/N450; Cz/N550; Cz/P750; and Pz/P1000. A vertex topography map was observed in the late Cz/N550-Cz/P750 and parietal topography in the very-late Pz/P1000 components. Consistent statistical values in the peak latencies and amplitudes were noted between consecutive investigations. The correlation between the pain intensity ratings and the major Cz/P750 amplitudes was highly significant in each study. Our validity tests suggested CHEPs to be useful for research and clinical applications in studying human pain activation related to thermal and nociceptive pathways.

Cerebral response to electric stimulation of the colon and abdominal skin in healthy subjects and patients with irritable bowel syndrome

BACKGROUND

Visceral hyperalgesia may play an important part in the pathophysiology of the irritable bowel syndrome (IBS). We investigated the neuronal afferent pathways in healthy volunteers and IBS patients by recording evoked potentials (EPs) elicited by electrical stimulation of the colon and abdominal skin inside and outside the referred pain area.

METHODS

Six healthy subjects and nine IBS patients met the inclusion criteria. Morphology and topography of EPs to painful electrical stimuli were estimated in the rectosigmoid junction and on the skin inside/outside the referred pain areas.

RESULTS

The EPs to painful stimuli of the gut showed a shorter latency and a smaller amplitude of the first positive peak (P1) in the IBS group. The controls had a mid-latency frontal positive component after 100 ms, whereas no reliable early activation was seen in the IBS patients. In controls, a single late (>150 ms) positive component was seen, whereas the late component was biphasic in the IBS group. The EPs to painful stimuli of the two skin areas differed in IBS patients, but not in controls.

CONCLUSION

Differences in the EPs to electrical painful stimulation of the sigmoid colon and skin inside/outside the experimentally evoked referred pain area were seen comparing healthy subjects and IBS patients. The results indicate altered central nervous system responses.

Compressive properties and function-composition relationships of developing bovine articular cartilage

The composition of cartilage is known to change during fetal and postnatal development. The objectives of this study were to characterize the compressive biomechanical properties of the 1 mm thick articular layer of cartilage of the distal femur from third-trimester bovine fetuses, from 1 to 3 week old bovine calf and from young adult bovine knees, and to correlate these properties with tissue components. The confined compression modulus increased 180% from the fetus to the calf and adult. The hydraulic permeability at 45% offset compression (relative to the free-swelling thickness) decreased by 70% from fetus to adult. These development-associated changes in biomechanical properties were primarily associated with a marked (approximately 2-3-fold) increase during development in collagen content and no detectable change in glycosaminoglycan (GAG) content. A role for collagen in the compressive properties of cartilage and the gradual increase in collagen during development suggest that collagen metabolism is critical for cartilage tissue engineering and repair therapies.

Different EEG topographic effects of painful and non-painful intramuscular stimulation in man

To clarify the specific effects of muscle pain on electroencephalogram (EEG) activation in man, painful and non-painful sensations were produced by intramuscular injections of capsaicin and vehicle solution in the left brachioradialis muscle, with identical procedures in 15 male volunteers. Thirty-one channel EEG data acquired before, during and after the two injections were analysed and compared in respect of topography and power spectrum. Although the painful and non-painful muscular stimulations evoked similar EEG topographic patterns, statistics demonstrated that distinct EEG activation over different areas of the head were induced by the painful and non-painful stimulation compared with the baselines. The decreases in theta and alpha-1 (8-10.5 Hz) activity in central and posterior parietal parts were evoked by non-painful stimulation, but the decreases in alpha-1 and alpha-2 (11-13.5 Hz) activities in the posterior part of the head were induced by painful stimulation. The alpha-2 activity augmented during the waning pain following a decrease in the overt pain. Comparing the EEG changes between baseline, non-painful and painful stimulations as well as waning pain, we found that the increase in beta-2 activity during muscle pain was significant over the extensive areas of the head, whereas a significant increase in alpha-2 activity took place at the posterior part of the head during waning pain following a marked decrease in overt pain. These results may imply that the painful and non-painful muscular stimulations evoke distinct EEG activation in different neural networks of the human brain and the intensity of nociceptive input from muscle may encode the variety of topographic EEG changes.

New perspectives in EEG/MEG brain mapping and PET/fMRI neuroimaging of human pain

With the maturation of EEG/MEG brain mapping and PET/fMRI neuroimaging in the 1990s, greater understanding of pain processing in the brain now elucidates and may even challenge the classical theory of pain mechanisms. This review scans across the cultural diversity of pain expression and modulation in man. It outlines the difficulties in defining and studying human pain. It then focuses on methods of studying the brain in experimental and clinical pain, the cohesive results of brain mapping and neuroimaging of noxious perception, the implication of pain research in understanding human consciousness and the relevance to clinical care as well as to the basic science of human psychophysiology. Non-invasive brain studies in man start to unveil the age-old puzzles of pain-illusion, hypnosis and placebo in pain modulation. The neurophysiological and neurohemodynamic brain measures of experimental pain can now largely satisfy the psychophysiologist's dream, unimaginable only a few years ago, of modelling the body-brain, brain-mind, mind-matter duality in an inter-linking 3-P triad: physics (stimulus energy); physiology (brain activities); and psyche (perception). For neuropsychophysiology greater challenges lie ahead: (a) how to integrate a cohesive theory of human pain in the brain; (b) what levels of analyses are necessary and sufficient; (c) what constitutes the structural organisation of the pain matrix; (d) what are the modes of processing among and across the sites of these structures; and (e) how can neural computation of these processes in the brain be carried out? We may envision that modular identification and delineation of the arousal-attention, emotion-motivation and perception-cognition neural networks of pain processing in the brain will also lead to deeper understanding of the human mind. Two foreseeable impacts on clinical sciences and basic theories from brain mapping/neuroimaging are the plausible central origin in persistent pain and integration of sensory-motor function in pain perception.

A morphologic, biochemical, and biomechanical assessment of short-term effects of osteochondral autograft plug transfer in an animal model

PURPOSE

The objective of this study was to assess the short-term changes that occur after an osteochondral autograft plug transfer from the femoral trochlea to the medial femoral condyle in a goat model.

TYPE OF STUDY

Articular cartilage repair animal study.

METHODS

Six adult male goats were used in this study. Two 4.5-mm osteochondral plugs were transferred from the superolateral femoral trochlea to 2 recipient sites in the central portion of the medial femoral condyle for a survival period of 12 weeks. Postmortem, the global effects of the procedure were assessed by gross morphologic inspection and by analyzing the synovial DNA for inflammatory response. The recipient sites were also evaluated histologically and biomechanically. Metabolic activity was determined by (35)SO(4) uptake, and viability was assessed using a live/dead stain and by confocal laser microscopy.

RESULTS

There was no evidence of significant gross morphologic or histologic changes in the operative knee as a result of the osteochondral donor or recipient sites. The patella, tibial plateau, and medial meniscus did not show any increased degenerative changes as a result of articulating against the donor or recipient sites of the osteochondral autografts. Analysis of synovial DNA revealed no inflammatory response. Biomechanically, 6- to 7-fold greater stiffness was noted in the cartilage of the transferred plugs compared with the control medial femoral condyle. Furthermore, on histologic examination, the healing subchondral bone interface at the recipient site had increased density. Glycosaminoglycan synthesis as determined by (35)SO(4) uptake was upregulated in the transplanted cartilage plug relative to the contralateral control, showing a repair response at the site of implantation. And finally, confocal microscopy showed 95% viability of the transferred plugs in the medial femoral condyle region.

CONCLUSIONS

Our findings demonstrate the ability to successfully transfer an osteochondral autograft plug with maintenance of chondrocyte cellular viability. The transferred cartilage is stiffer than the control medial femoral condyle cartilage, and there is concern regarding the increased trabecular mass in the healing subchondral plate, but these do not result in increased degenerative changes of the opposing articular surfaces in the short term.

Formulation of PEG-based hydrogels affects tissue-engineered cartilage construct characteristics

The limited supply of cartilage tissue with appropriate sizes and shapes needed for reconstruction and repair has stimulated research in the area of hydrogels as scaffolds for cartilage tissue engineering. In this study we demonstrate that poly(ethylene glycol) (PEG)-based semi-interpenetrating (sIPN) network hydrogels, made with a crosslinkable poly(ethylene glycol)-dimethacrylate (PEGDM) component and a non-crosslinkable interpenetration poly(ethylene oxide) (PEO) component, and seeded with chondrocytes support cartilage construct growth having nominal thicknesses of 6 mm and relatively uniform safranin-O stained matrix when cultured statically, unlike constructs grown with prefabricated macroporous scaffolds. Even though changing the molecular weight of the PEO from 100 to 20 kDa reduces the viscosity of the precursor polymer solution, we have demonstrated that it does not appear to affect the histological or biochemical characteristics of cartilaginous constructs. Extracellular matrix (ECM) accumulation and the spatial uniformity of the ECM deposited by the embedded chondrocytes decreased, and hydrogel compressive properties increased, as the ratio of the PEGDM:PEO in the hydrogel formulation increased (from 30:70 to 100:0 PEGDM:PEO). Total collagen and glycosaminoglycan contents per dry weight were highest using the 30:70 PEGDM:PEO formulation (24.4+/-3.5% and 7.1+/-0.9%, respectively). The highest equilibrium compressive modulus was obtained using the 100:0 PEGDM:PEO formulation (0.32+/-0.07 MPa), which is similar to the compressive modulus of native articular cartilage. These results suggest that the versatility of PEG-based sIPN hydrogels makes them an attractive scaffold for tissue engineering of cartilage.

Somatosensory event-related potential and autonomic activity to varying pain reduction cognitive strategies in hypnosis

OBJECTIVES

The issues of differential effects among cognitive strategies during hypnosis in the control of human pain are under active debate. This study, which employs measures of pain perception, electrocortical and autonomic responses, was aimed at determining these pain-related modulations.

METHODS

Somatosensory event-related potentials (SERPs) to noxious stimuli under an odd-ball paradigm were recorded at the frontal, temporal and parietal regions in 10 high, 9 mid, and 10 low hypnotizable right-handed young women, at waking baseline, varying cognitive strategies (deep relaxation, dissociative imagery, focused analgesia) in hypnosis and placebo conditions. The phasic heart rate (HR) and skin conductance response were also recorded. The analysis was focused on the frequent standard trials of the odd-ball SERPs. Repeated measures analysis of variance was conducted to examine the experimental effects.

RESULTS

Focused analgesia induced the largest reduction in pain rating, more in the high than low hypnotizable subjects. In high hypnotizable subjects, the N2 amplitude was greater over frontal and temporal scalp sites than over parietal and central sites, whereas in moderately and low hypnotizable subjects, N2 was greater over temporal sites than over frontal, parietal, and central sites. These subjects also displayed a larger N2 peak over temporal sites during focused analgesia than in the other conditions. The P3 amplitude was smaller under deep relaxation, dissociative imagery and focused analgesia in the high hypnotizable subjects. For these subjects, the smallest P3 peaks were obtained for dissociated imagery and focused analgesia over frontal and temporal sites. In contrast, for the P3 peak, low hypnotizable subjects failed to show significant condition effects. In all of the subjects, the skin conductance and HR were smaller during hypnotic suggestions than in the waking state.

CONCLUSIONS

The effect of pain modulation is limited to high hypnotizable subjects rather than low hypnotizable ones. Higher frontal-temporal N2 and smaller posterior parietal P3 may indicate active inhibitory processes during cognitive strategies in hypnotic analgesia. These inhibitory processes also regulate the autonomic activities in pain perception.

Topographic effects of tonic cutaneous nociceptive stimulation on human electroencephalograph

To examine the specific effects of cutaneous pain on electroencephalographic (EEG) activities, tonic painful and non-painful sensations in left forearm were induced by intradermal injection of capsaicin 100 microg/20microl and the same volume of vehicle, respectively, in 15 healthy males. The EEG data acquired in five experimental conditions: (i) baseline A; (ii) non-painful vehicle injection; (iii) baseline B; (iv) painful capsaicin injection and (v) waning pain, were analyzed and compared with analysis of variance. Only the painful capsaicin injection evoked significant decreases of theta, alpha-1 and alpha-2 powers over the centro-parieto-occipital regions compared with baseline B. No significant difference in EEG activation between the non-painful vehicle injection and painful capsaicin injection was found. This implicates that the observed topographic EEG activation is not specific for pain but probably related to the cutaneous stimulation.

Nitrogen removal from sewage by continuous flow SBR system with intermittent aeration

A continuous-flow sequential batch reactor system with intermittent aeration known as the intermittent cycle extended aeration system was used to investigate the efficiencies of nitrogen removal for sewage. In the conventional intermittent cycle extend aeration system with continuous aeration process to treat the synthetic sewage wastewater under 3 cycles per day (cycle time = 8 hours), high COD removal efficiencies were achieved, but high levels of nitrate (22.3-23.6 mg l-1) and decreased pH values were also found in the effluent. In the intermittent aeration, the dissolved oxygen in the reactor was reduced from the range of 3.5-5.0 mg l-1 to 0.5-1.2 mg l-1, the nitrogen in the influent was partially oxidized to nitrite-nitrogen, although nitrate-nitrogen was also present in the effluent. In detailed cyclic study of the reactor with relatively low D.O. (0.3-1.0 mg l-1) and high MLSS (3200 mg l-1 at half full water level), the experimental results of intermittent aeration processes showed higher oxidation rates of ammonia to nitrite (1.44-3.55 mg N g-1 MLSS hr-1) than the conversion rates of nitrite to nitrate (0.00-1.22 mg N g-1 MLSS hr-1). It was thus, concluded that denitrification rates were not affected by the limited supplement of soluble organic carbon in the system. In addition, NOx(-)-N could be removed with a total nitrogen removal rate up to 94.9% when the MLSS was controlled in concentrations of 3200 mg l-1 at half full water level with low D.O. The process of intermittent aeration of ICEAS could provide an economic and effective means for nitrogen removal in treating sewage.

Expression of the cAMP response element binding protein (CREB) in hippocampus produces an antidepressant effect

BACKGROUND

Recent studies have demonstrated that chronic antidepressant treatment increases the expression of the cyclic amp (cAMP) response element binding protein (CREB) in rat hippocampus. The study presented here was conducted to determine if CREB is a relevant target that produces an antidepressant-like effect.

METHODS

We employed the herpes simplex virus (HSV)-mediated gene transfer technique to overexpress CREB and determined its effect on the learned helplessness and forced swim tests, two established models used for pharmacological screening of antidepressant drugs.

RESULTS

In the learned helplessness model, rats that received bilateral microinjection of HSV-CREB into the dentate gyrus showed significantly fewer escape failures in the subsequent conditioned avoidance test than those injected with control vector (HSV-LacZ). In contrast, microinjection of HSV-CREB in either the CA1 pyramidal cell layer of hippocampus or the prefrontal cortex did not produce an antidepressant response. In the forced swim test, CREB expression in the dentate gyrus resulted in a significantly shorter immobility time than those injected with HSV-LacZ.

CONCLUSIONS

These results demonstrate that over-expression of CREB in hippocampus results in an antidepressant effect and suggest that CREB may serve as a potential molecular target for novel therapeutic agents.

Gating of the vertex somatosensory and auditory evoked potential P50 and the correlation to skin conductance orienting response in healthy men

A defect in auditory evoked potential (AEP) P50 gating supports the theory of information-processing deficits in schizophrenia. The relationship between gating of the mid-latency evoked potentials (EP) in the somatosensory and the auditory modalities has not been studied together before. In schizophrenia, we might expect the processing deficits to act on multiple modalities. We have examined the gating of median nerve somatosensory EP (SEP) following paired stimulation identical to the AEP P50 gating paradigm using interstimulus intervals (ISI) of 500, 750 and 1000 ms and the correlation of gating to the skin conductance orienting response (SCOR) in 20 healthy men. We measured mid-latency vertex components (SEP: P50, N65, P85 and N100; AEP: P30, N45, P50 and N80). The gating was most pronounced at ISI 500 ms where the SEP P50 and N100 gating were 0.59 and 0.37, respectively, as compared to a gating of 0.61 in P30, 0.33 in P50 and 0.45 in N80 in the AEP. Repetition effects in the two modalities were not correlated. AEP P50 gating was correlated to skin conductance level (SCL). The combination of recording repetition effects on the mid-latency EP in two modalities could provide a method for investigating if deficits of information processing in schizophrenia are cross-modal.

Cerebral dynamics of SEPS to non-painful and painful cutaneous electrical stimulation of the thenar and hypothenar

Early, middle and late latency somatosensory evoked potentials (SEPs) elicited by cutaneous electrical stimulation (painful vs. non-painful) of right and left hands were recorded. The aims were to study (1) if lifelong use of dominant right hand would result in different SEP topographies compared to non-dominant left hand stimulation, (2) if painful and non-painful stimuli resulted in different SEP activation patterns for the different latency components and (3) if these results were consistent between two areas of the hand. Electrical stimuli were applied cutaneously above the thenar and hypothenar muscles of the left and right hand. A two-way repeated measures ANOVA was used to test the effects of laterality and intensity for a given peak amplitude and latency. Statistical results yielded no significant difference in peak amplitude for either thenar and hypothenar between the two hands. In contrast, a significant difference in amplitude was observed for 6 components for each stimulus location when the two intensities were compared. These components were found at early, middle and late latencies. No significant latency shift was observed between the two hands. Only the P30 component showed a significant latency shift for both locations with the painful condition having the shorter latency. Thus, life-long use of the dominant hand does not generate detectable changes in cortical evoked activity to sensory input from the skin above thenar and hypothenar muscles. Several SEP components across the time course (0-400 ms) showed increased amplitude when the stimulus was increased from non-painful to painful intensity.

Brain dynamics of scalp evoked potentials and current source densities to repetitive (5-pulse train) painful stimulation of skin and muscle: central correlate of temporal summation

Temporal summation is a potent central somatosensory mechanism and may be a major mechanism involved in e.g. neuropathic pain. This study assessed the long-latency somatosensory evoked potentials (SEPs) in response to trains of repeated painful electrical stimulation of human skin and muscle in order to investigate the cerebral representation of temporal summation. Forty series of stimuli were delivered at stimulus intensities corresponding to moderate pain levels in 20 young men. Each series consisted of a five-burst-pulses (1 ms) train delivered at 2 Hz, known to activate temporal summation, i.e. increased pain intensity during the series of stimuli. Grand mean averaged waveforms (31 ch. EEG) were obtained in response to the skin and muscle stimulation. In the "train" SEPs, the wave morphology was characterized by four peak components after the first stimulus (100 to 450 ms) and by three components after the fifth stimulus (2100-2145 ms). The latency was significantly prolonged for muscle stimulation only. The 3D topographic maps at the peak activation time (100, 140, 250, and 450 ms) showed clear reduction in the amplitudes and their spatial extent (P4/P100-Fc2/N100, POz/P140-Fc2/N140, Cz/P250, Cz/N460) betweenthe first and the fifth stimulus. The current source density (CSD) topology exhibited markedly differential patterns changing from the first to the fifth stimulus. For the skin stimulation, the fifth stimulus was associated with a distinct emergence of the frontal negativity source at Fc2 right frontal cortex. This was consistent across the 100,140, 250, and 450 peak components but was not even visible in the first stimulus. In the muscle, the fifth stimulus was associated with a marked reduction of the frontal positivity at contralateral F4 site in the early stages at 100 and 140 ms, and with a total disappearance of positive source at Cz. In summary, this study demonstrated a clear temporal summation of psychophysical ratings, reduction of the peak amplitudes in the last of the first stimuli, dissociation from simple amplitude increase of the cerebral responses to pain, and a concurrent transformation of the CSD patterns. This change in "rapid cortical dynamics" of short-term plasticity could be an important mechanism for wind-up and pain processing in the brain.

Dynamic brain topography of somatosensory evoked potentials and equivalent dipoles in response to graded painful skin and muscle stimulation

The differential effects of painful stimulation of skin vs. muscle on the cerebral electrophysiology have been poorly described. This study examined the somatosensory evoked potentials (SEPs) and the associated dipole models of non-painful and graded painful electrical stimulation applied to the skin and muscle in 20 healthy subjects. With the psychophysical stimulus-response functions determined, the skin stimulation showed a steeper slope than muscle stimulation. For both types of stimulation, the SEPs indicated a similar temporo-spatial activation sequence: F4/N90-P4/P95, Fc2/N135, Cz/P250, Cz/P300, and Cz/N460. The SEP amplitudes increased significantly with the stimulus intensities in these components. The peak SEP latencies of skin stimulation were in general shorter than that of muscle stimulation. The SEP amplitudes to skin stimulation were significantly larger than those caused by muscle stimulation at every stimulus intensity level, except the early mid-latency component. In this case, muscle stimulation caused higher amplitudes over the contralateral parietal-frontal sites. For both types of stimulation, the topographic maps were quite similar. Equivalent dipole modeling revealed identical site parameters (<1.0 cm) between skin and muscle stimulation. However, the electrical skin stimulation did not correlate with the pain intensity. Pain intensity, in contrast, was uniquely associated with the Cz/P250 amplitudes for the muscle stimulation. It is concluded that non-nociceptive and nociceptive electrical stimuli applied to skin and muscle are processed in the common cerebral areas, but exhibit differential SEP effects.