Faculty Bibliography

PURPOSE: We studied factors that can predict successful repeat microdissection testicular sperm extraction in men with nonobstructive azoospermia. MATERIALS AND METHODS: We retrospectively analyzed the records of 126 men with nonobstructive azoospermia who underwent 1 successful microdissection testicular sperm extraction attempt. Clinical factors identifiable at the second procedure, including age, testicular volume, endocrinological data and histology, were analyzed. RESULTS: Overall testicular spermatozoa were successfully retrieved at 103 of 126 repeat attempts (82%). Men with a successful repeat attempt had lower follicle-stimulating hormone (mean+/-SD 23.1+/-12.4 vs 29.2+/-12.8, p=0.04) and larger testicular volume (mean 10+/-5 vs 7+/-4, p=0.0001) at the repeat procedure compared to men with a failed repeat attempt. Adjusted associations from a multiple logistic regression model showed that no factors predicted sperm retrieval during repeat microdissection testicular sperm extraction. An ROC curve showed a fair prediction model (AUC=0.71). CONCLUSIONS: The follicle-stimulating hormone level and testicular volume at the repeat attempt appear to have predictive value to determine the success of a second attempt. These observations are interesting since testicular volume and follicle-stimulating hormone in men with nonobstructive azoospermia do not predict sperm retrieval at a primary microdissection testicular sperm extraction attempt.

OBJECTIVE: This study tested the hypothesis that bond strength of total- and self-etching adhesive systems to dentine is not affected by the presence of remnants from either eugenol-containing (EC) or eugenol-free (EF) temporary cements after standardized cleaning procedures. METHODS: Thirty non-carious human third molars were polished flat to expose dentine surfaces. Provisional acrylic plates were fabricated and cemented either with EC, EF or no temporary cements. All specimens were incubated for 7 days in water at 37 degrees C. The restorations were then taken out and the remnants of temporary cements were mechanically removed with a dental instrument. The dentine surfaces were cleaned with pumice and treated with either total-etching (TE) or self-etching (SE) dental adhesive systems. Atomic force microscopy was used to examine the presence of remnants of temporary cements before and after dentine cleaning procedures. Composite resin build-ups were fabricated and cemented to the bonded dentine surfaces with a resin luting cement. The specimens were then sectioned to obtain 0.9mm(2) beams for microtensile bond strength testing. Fractographic analysis was performed by optical and scanning electron microscopy. RESULTS: ANOVA showed lower mean microtensile bond strength in groups of specimens treated with EC temporary cement than in groups treated with either no cement or an EF cement (p<0.05). Mean microtensile bond strength was lower in groups employing the SE rather than the TE adhesive system (p<0.001). SE samples were also more likely to fail during initial processing of the samples. There was no evidence of interaction between cement and adhesive system effects on tensile strength. Fractographic analysis indicated different primary failure modes for SE and TE bonding systems, at the dentine-adhesive interface and at the resin cement-resin composite interface, respectively. CONCLUSION: The use of eugenol-containing temporary cements prior to indirect bonding restorations reduce, to a statistically similar extent, the bond strength of both total- and self-etching adhesive systems to dentine

INTRODUCTION: Lymphedema is the chronic swelling of an extremity that occurs commonly after lymph node resection for cancer treatment. Recent studies have demonstrated that transfer of healthy tissues can be used as a means of bypassing damaged lymphatics and ameliorating lymphedema. The purpose of these studies was to investigate the mechanisms that regulate lymphatic regeneration after tissue transfer. METHODS: Nude mice (recipients) underwent 2-mm tail skin excisions that were either left open or repaired with full-thickness skin grafts harvested from donor transgenic mice that expressed green fluorescent protein in all tissues or from LYVE-1 knockout mice. Lymphatic regeneration, expression of VEGF-C, macrophage infiltration, and potential for skin grafting to bypass damaged lymphatics were assessed. RESULTS: Skin grafts healed rapidly and restored lymphatic flow. Lymphatic regeneration occurred beginning at the peripheral edges of the graft, primarily from ingrowth of new lymphatic vessels originating from the recipient mouse. In addition, donor lymphatic vessels appeared to spontaneously re-anastomose with recipient vessels. Patterns of VEGF-C expression and macrophage infiltration were temporally and spatially associated with lymphatic regeneration. When compared to mice treated with excision only, there was a 4-fold decrease in tail volumes, 2.5-fold increase in lymphatic transport by lymphoscintigraphy, 40% decrease in dermal thickness, and 54% decrease in scar index in skin-grafted animals, indicating that tissue transfer could bypass damaged lymphatics and promote rapid lymphatic regeneration. CONCLUSIONS: Our studies suggest that lymphatic regeneration after tissue transfer occurs by ingrowth of lymphatic vessels and spontaneous re-connection of existing lymphatics. This process is temporally and spatially associated with VEGF-C expression and macrophage infiltration. Finally, tissue transfer can be used to bypass damaged lymphatics and promote rapid lymphatic regeneration.

Homeostasis and wound healing rely on stem cells (SCs) whose activity and directed migration are often governed by Wnt signaling. In dissecting how this pathway integrates with the necessary downstream cytoskeletal dynamics, we discovered that GSK3β, a kinase inhibited by Wnt signaling, directly phosphorylates ACF7, a > 500 kDa microtubule-actin crosslinking protein abundant in hair follicle stem cells (HF-SCs). We map ACF7's GSK3β sites to the microtubule-binding domain and show that phosphorylation uncouples ACF7 from microtubules. Phosphorylation-refractile ACF7 rescues overall microtubule architecture, but phosphorylation-constitutive mutants do not. Neither mutant rescues polarized movement, revealing that phospho-regulation must be dynamic. This circuitry is physiologically relevant and depends upon polarized GSK3β inhibition at the migrating front of SCs/progeny streaming from HFs during wound repair. Moreover, only ACF7 and not GSKβ-refractile-ACF7 restore polarized microtubule-growth and SC-migration to ACF7 null skin. Our findings provide insights into how this conserved spectraplakin integrates signaling, cytoskeletal dynamics, and polarized locomotion of somatic SCs.

BACKGROUND: Occult breast carcinoma is occasionally found in reduction mammaplasty specimens. Historically, these patients were treated with mastectomy because the exact location of the tumor was unknown. Currently, breast conservation is the treatment of choice in 50 to 85 percent of breast cancers. The authors present a technique of routine specimen marking that allows localization of the tumor and preservation of the choice of lumpectomy. METHODS: This is a retrospective review of 866 patients who underwent reduction mammaplasty performed by a single surgeon between 1990 and 2009. Data were collected for patients who had occult cancer found in their specimens, including age, cancer risk factors, abnormality, nodal status, selected treatment, and survival status. Specimens were marked and oriented and then sent in separate bags to the pathologist. RESULTS: There were 10 cases of occult carcinoma among the 866 women (1.15 percent) who underwent reduction mammaplasty. Six cancers were found in patients undergoing reduction for symptomatic macromastia [n = 629 (0.95 percent)]. Four new cancers were found in the group of patients with a personal history of cancer [n = 237 (1.69 percent)]. All 10 patients had normal preoperative mammograms. Location, size, and margin status were easily identified and patients were offered the choice of lumpectomy or mastectomy. CONCLUSIONS: This article demonstrates that careful marking of reduction specimens in high-risk patients or in women older than 40 years allows the pathologist to orient, localize, and further section tissue for margin status. Communication among plastic surgeon, pathologist, oncologist, and radiation therapist preserves the choice of breast conserving therapy for early cancers.

Fifty-seven adult patients with facial paralysis, who underwent direct muscle neurotisation, were reviewed and divided into three categories depending on the function that direct neurotisation was aiming to augment. Group 1 included 30 patients who underwent direct neurotisation for eye closure and blink, group 2 consisted of 23 patients for smile augmentation, and group 3 comprised 31 patients for depressor. The age of the patients ranged from 21 to 74 years. Denervation time (Dt) ranged from 8 months to 42 years. Eight patients had partial facial paralysis, and 49 patients had complete facial paralysis. The results were based on the functional and electromyography (EMG) scoring of the neurotised muscles showing an overall EMG mean improvement of 26.56% in eye closure, 34.47% in smile restoration and 32.67% in depressor function by the procedure. Median improvement in all facial functions was one grade (25%) in theTerzis grading systems regarding the respective facial functions. The prerequisites are Dt less than 6 months and a functional contralateral facial nerve. In cases where Dt is more than 27 months and preoperative EMG's are silent, a free or pedicled muscle should be used to substitute the denervated native facial muscle. Promoting expressivity and augmenting facial muscle function using direct muscle neurotisation are important components in facial reanimation