Long-Term Sensitivity and Patient-Reported Functionality of the Neoclitoris After Gender Reassignment Surgery.

INTRODUCTION: A cornerstone of treating gender dysphoria for transgender women is gender reassignment surgery (GRS) encompassing vaginoplasty and clitoroplasty. The neoclitoris is harvested as a flap with a neurovascular pedicle from the proximal dorsal part of the glans penis. Few long-term follow-ups exist on postoperative sensation and patient-reported sexual functionality of the neoclitoris. AIM: To examine the sensitivity of the neoclitoris and its relation to orgasm and sexual function at least 1 year after GRS. METHODS: Twenty-two patients were included, with a mean follow-up of 37 months (range = 12-63) after initial surgery. Tactile and vibratory sensitivities were measured with Semmes-Weinstein monofilaments and the Bio-Thesiometer vibratory measurement device, respectively. A questionnaire was provided to the patients, as were interview questions about body image, orgasm, pain, and general satisfaction with the surgery. MAIN OUTCOME MEASURES: Tactile and vibratory sensitivities of the neoclitoris and questionnaire on satisfaction with orgasm, sexual function, and general satisfaction. RESULTS: The average tactile threshold for the clitoris was 12.5 g/mm2 and the average vibratory threshold was 0.3 µm. Most participants (86%) experienced orgasm after surgery, had no or little pain, and were satisfied with the surgery. No statistical correlation was found between better or worse objective pressure and vibratory thresholds and patient answers to questions about the clitoris in the Body Image Scale for Transsexuals questionnaire. CONCLUSION: The neoclitoris derived from the glans penis in GRS provides long-term clitoral sensation that is erogenous. Overall, the vast majority of patients who undergo male-to female GRS experience orgasm and are satisfied with the surgery.

Histone H2AX-dependent GABA(A) receptor regulation of stem cell proliferation.

Stem cell self-renewal implies proliferation under continued maintenance of multipotency. Small changes in numbers of stem cells may lead to large differences in differentiated cell numbers, resulting in significant physiological consequences. Proliferation is typically regulated in the G1 phase, which is associated with differentiation and cell cycle arrest. However, embryonic stem (ES) cells may lack a G1 checkpoint. Regulation of proliferation in the 'DNA damage' S/G2 cell cycle checkpoint pathway is known for its role in the maintenance of chromatin structural integrity. Here we show that autocrine/paracrine gamma-aminobutyric acid (GABA) signalling by means of GABA(A) receptors negatively controls ES cell and peripheral neural crest stem (NCS) cell proliferation, preimplantation embryonic growth and proliferation in the boundary-cap stem cell niche, resulting in an attenuation of neuronal progenies from this stem cell niche. Activation of GABA(A) receptors leads to hyperpolarization, increased cell volume and accumulation of stem cells in S phase, thereby causing a rapid decrease in cell proliferation. GABA(A) receptors signal through S-phase checkpoint kinases of the phosphatidylinositol-3-OH kinase-related kinase family and the histone variant H2AX. This signalling pathway critically regulates proliferation independently of differentiation, apoptosis and overt damage to DNA. These results indicate the presence of a fundamentally different mechanism of proliferation control in these stem cells, in comparison with most somatic cells, involving proteins in the DNA damage checkpoint pathway.

Oversized design of the anterolateral thigh flap for head and neck reconstruction.

Most surgical protocols for head and neck cancer extirpation require concurrent neck lymph node dissection. Hence, the defect involves not only the cancerous anatomical structures but also the neck. The tissue deficiency in the latter region imposes potential problems such as carotid and jugular vein exposure risking blowout, infections and orocutaneous fistulae in the neck, and a cosmetically untoward sunken appearance. The free anterolateral thigh flap (ALT) provides abundant tissue and is often the flap of choice in head and neck reconstruction. To replace the proper amount of postoperative soft tissue deficit in the neck area, we use an oversized ALT flap design. This allows reconstruction of the specific anatomical defects, protection of the important neck structures, and prevention of a sunken appearance. An oversized flap may also provide additional coverage for fixation hardware to prevent its exposure, especially after radiotherapy. In the event of partial flap loss, some viable parts of the oversized flap may be possible to advance or rotate to replace the nonviable part to avoid a repeated free flap procedure or other more complicated reconstructive procedures.

Cell migration by a FRS2-adaptor dependent membrane relocation of ret receptors.

During development neural progenitor cells migrate with extraordinary precision to inhabit tissues and organs far from their initial position. Little is known about the cellular basis for directional guidance by tyrosine kinase receptors (RTKs). RET is a RTK with important functions in guiding the migration of neuronal cells, and RET dysregulation leads to clinical disease such as agangliosis of the colon. We show here that RET migration in neuroepitheliomal and non-neuronal cells is elicited by the activation of specific signaling pathways initiated by the competitive recruitment of the FRS2 adaptor molecule to tyrosine 1062 (Y1062) in RET. FRS2 selectively recruited RET to focal complexes and led to activation of SRC family kinases and focal adhesion kinase (FAK). Activation of SRC depended on its direct interaction with RET at a different intracellular tyrosine (Y981) and activation of molecular signaling from these two separate sites in concert regulated migration. Our data suggest that an important function for FRS2 is to concentrate RET in membrane foci, leading to an engagement of specific signaling complexes localized in these membrane domains.

Differential expression and dynamic changes of murine NEDD9 in progenitor cells of diverse tissues.

NEDD9 is a scaffolding protein in the integrin signaling pathway that is involved in cell adhesion dynamics. Little is known of the cellular localization of NEDD9 expression during embryonic development. In the present study, we have analyzed NEDD9 mRNA expression in the mouse and identified new relevant expression sites. In addition, we have characterized NEDD9 protein expression pattern for the first time in mammals. At E9.5-E10.5, high levels of Nedd9 and the neurogenic transcription factor neurogenin-2 (Ngn2) were found to largely overlap in two discrete domains of the trunk neural tube along its dorso-ventral axis, with Nedd9 extending to more ventral regions of the ventricular zone and Ngn2 differentially expressed in neuronally committed progenitors of the intermediate zone. At encephalic and trunk levels of the neural tube, NEDD9 was present in Sox2(+) progenitor cell populations mostly generating Ngn2(+) and/or Nurr1(+) cells. A sharp down-regulation of NEDD9 expression was found in cells upon lineage commitment, as observed in Nurr1(+) and Ngn2(+) mesencephalic dopaminergic and brainstem neuronal progenitors. In other tissues/organs, i.e. prospective heart, retina, olfactory epithelium, gonads, cartilage, gut and pituitary gland, NEDD9 was found to be co-expressed with Sox2, RXR alpha and/or Nurr1-like proteins, suggesting that NEDD9 expression is confined to early progenitors involved in diverse organogenesis and that it may depend on the repertoire and levels of retinoic acid co-receptors expressed by those cells.

Subcellular receptor redistribution and enhanced microspike formation by a Ret receptor preferentially recruiting Dok.

Ret is a receptor tyrosine kinase for the GDNF family of ligands and plays important roles during nervous system development for cell proliferation, cell migration and neurite growth. Signaling initiated from intracellular tyrosine 1062, by recruitment of several different phosphotyrosine binding (PTB) proteins (i.e. Shc, Frs2 and Dok), is important for these biological effects. By a single amino acid substitution in the PTB domain binding sequence of Ret, we have rewired the receptor such that it preferentially recruits Dok (Ret(Dok+)) with little or no remaining interactions with Shc and Frs2. Ret(Dok+) displays a sustained MAP kinase activation and a loss of Akt signaling compared to Ret(WT). We show that early events after ligand stimulation of Ret(Dok+) include massive formation of fine microspikes that are believed to be priming structures for neurite growth from the cell soma. The Ret(Dok+) receptors relocated in the membrane compartment into focal clusters at the tip of the microspikes, which was associated with Cdc42 activation. These results suggest that engagement of different adaptor proteins by Ret results in very different downstream signaling and functions within neurons and that Dok recruitment leads to a rapid receptor relocation and formation of microspikes.

Midface Osteotomies for Feminization of the Facial Skeleton.

Facial feminization surgery is a term to describe the surgical alteration of a masculine facial appearance to a more feminine appearance, which is most commonly performed for male-to-female transsexual individuals. To alter the midfacial relations, segmentalized osteotomies were performed in selected patients expanding on the established techniques for facial feminization surgery. All patients underwent a preoperative 3D computerized tomography scan and 3D photography before and after the surgery. The inclusion of the midface in surgery was determined based on the relative projection and angle of the zygomatic body compared with the supraorbital region (the supraorbital region was reduced in all patients). Patients were prospectively followed up by 3D surface photography and 3D computerized tomography scans. Rotation and advancement of the zygomatic region was found to be an effective way to further feminize the midfacial appearance in selected male-to-female transsexual patients. No major surgical complications occurred. Although somewhat technically challenging, we suggest that midface surgery should be considered for feminizing purposes in order for the patient to achieve a long-term favorable result compared with other alternative methods.

Long-term sensory disturbances after orbitozygomatic fractures.

BACKGROUND: Orbitozygomatic fractures often lead to infraorbital nerve (ION) injury, and affected sensibility is a common long-term complaint within this patient group. We present a long-term follow-up study where the validated von Frey filament system was used for testing ION sensibility. Furthermore, we examined the incidence of persistent nerve injury and whether more complex fractures led to more pronounced ION sensibility disturbances. METHODS: Patients treated for facial fractures involving the orbitozygomatic complex were included and the follow-up time was 3 years or more. Depending on the location and severity of the fractures, the patients were divided into 4 groups. The patients answered a questionnaire before ION sensibility testing with von Frey filaments. RESULTS: Eighty-one patients were examined: 65 males (80%) and 16 females (20%). Examinations were conducted between 3.0 and 7.6 years (mean 4.9 years) after injury. Sixteen patients (20%) had affected and 6 patients (7.4%) had severely affected ION sensibility according to von Frey testing. No statistically significant differences were found in terms of questionnaire score between the groups. There was also no statistically significant correlation between questionnaire results and log von Frey values. Although the effect of groups could not be statistically verified using the log von Frey values, a larger proportion of patients with complex fractures had higher log von Frey values than the other groups. CONCLUSIONS: Patients with complex fractures report more permanent sensory disturbance of the ION after surgery than those with isolated orbitozygomatic fractures, although this could not be verified statistically with von Frey filament testing at several locations. Hence, a validated method for testing facial sensibility such as von Frey filaments, although sensitive, is inadequate to determine all aspects of sensory malfunction after orbitozygomatic fractures. This suggests that the patient's experience of long-term sensation after trauma may not be correlated with objective measures.

Quality of life improves early after gender reassignment surgery in transgender women.

BACKGROUND: Few studies have examined the long-term quality of life (QoL) of individuals with gender dysphoria, or how it is affected by treatment. Our aim was to examine the QoL of transgender women undergoing gender reassignment surgery (GRS). METHODS: We performed a prospective cohort study on 190 patients undergoing male-to-female GRS at Karolinska University Hospital between 2003 and 2015. We used the Swedish version of the Short Form-36 Health Survey (SF-36), which measures QoL across eight domains. The questionnaire was distributed to patients pre-operatively, as well as 1, 3, and 5 years post-operatively. The results were compared between the different measure points, as well as between the study group and the general population. RESULTS: On most dimensions of the SF-36 questionnaire, transgender women reported a lower QoL than the general population. The scores of SF-36 showed a non-significant trend to be lower 5 years post-GRS compared to pre-operatively, a decline consistent with that of the general population. Self-perceived health compared to 1 year previously rose in the first post-operative year, after which it declined. CONCLUSIONS: To our knowledge, this is the largest prospective study to follow a group of transgender patients with regards to QoL over continuous temporal measure points. Our results show that transgender women generally have a lower QoL compared to the general population. GRS leads to an improvement in general well-being as a trend but over the long-term, QoL decreases slightly in line with that of the comparison group. Level of evidence: Level III, therapeutic study.

Solely Penile Skin for Neovaginal Construction in Sex Reassignment Surgery.

BACKGROUND: Gender reassignment surgery due to transsexualism (International Classification of Diseases, Tenth Revision: F64.0) is a procedure becoming increasingly common worldwide as a result of a significant increase in diagnostic incidence. Several methods have been described for this complex surgery, but no internationally agreed upon gold standard exists, in particular with regard to which methods allow for creating a sufficient neovaginal depth. METHODS: We use a 2-stage technique using solely penile skin for creating a neovaginal cavity and present the long-term outcome in terms of measured neovaginal depth. Eighty patients were included. Patients' neovaginal depth was measured in a standardized fashion 6 months or more after initial surgery. Results were compared with published data on female anatomy. RESULTS: The average neovaginal depth achieved was 10.2 cm. Having had a postoperative complication and noncompliance to neovaginal dilatation were both negatively correlated with neovaginal depth, whereas higher body mass index was not. Most patients received a neovaginal depth sufficient for penetrative intercourse and within the range for biological women. CONCLUSIONS: Using solely penile skin for the vaginal lining is a satisfactory surgical method to achieve adequate vaginal depth, provided that the postoperative dilatation regimen is followed. This holds true regardless of age or body mass index.

Composite orbital reconstruction using the vascularized segmentalized osteo-fascio-cutaneous fibula flap.

Reconstruction of composite orbital defects must address the orbit and an exposed skull base and/or maxillary region. The orbit should not only be covered but also reshaped to accommodate the orbital contents or an epithesis when warranted. This study presents a rationale for a near-anatomical reconstruction of the orbit, together with adjacent dead space obliteration, using the segmentalized osteo-fascia-cutaneous fibula flap. Before the flap transfer, a cutting template for the fibula is made according to the measures and requirements of the facial defect. The segmentalized bone is then osteosynthesized to the facial skeleton and revascularized. Thus, an orbital depth is created by the bony fibula, whereas the fascio-cutaneous part of the flap may be used for lining the orbit and obliteration of the skull base or the maxillary region, or resurface the palate and/or the nasal cavity.

Persistent diplopia after fractures involving the orbit related to nerve injury.

BACKGROUND: Fractures in the facial skeleton are common and may lead to orbital sequelae caused by the injury and/or the surgery. In this long-term follow-up, we examined the nature of sequelae after facial fractures involving the orbit and whether a higher complexity of the fractures produced more sequelae compared to simpler fracture patterns, and if so, to what extent. METHODS: Patients surgically treated for facial fractures involving the orbit at the Karolinska University Hospital with a follow-up duration of ≥3 years were included in this retrospective study and were examined by a neuro-ophthalmologist. Based on the location and severity of the fractures, the patients were divided into four groups according to fracture complexity: 1) isolated zygomatic fracture, 2) isolated orbital floor blowout fracture, 3) zygomatic fracture combined with blowout fracture and 4) bilateral or multiple fracture patterns. RESULTS: Out of 154 patients, 81 patients (53%) attended follow-up examinations, 65 male (80%) and 16 female (20%). The duration of follow-up was 3.0-7.6 years (mean of 4.9 years). The incidence of diplopia was 3.7%, visual loss 2.5%, dystopia 4.9% and visible enophthalmos (>2 mm) 8.6%. Severe diplopia (2.5%) was due to nerve injuries. Visual loss was encountered only in group 4 with complex fractures. Fracture complexity had an effect on the presence of any sequelae, with group 4 presenting a higher percentage of patients with sequelae than the other three groups. However, no statistically significant effect of group could be found on the individual, quantitative output values of dystopia and enophthalmos. CONCLUSIONS: In this study, severe persistent diplopia in patients was due to nerve injuries, which emphasizes the need for preoperative ophthalmologic examinations, in all patients with fractures involving the orbit. A higher fracture complexity was found to lead to a higher percentage of patients presenting sequelae.

Development of a bioactive implant for repair and potential healing of cranial defects.

The repair of complex craniofacial bone defects is challenging and a successful result is dependent on the size of the defect, quality of the soft tissue covering the defect, and choice of reconstruction method. The objective of this study was to develop a bioactive cranial implant that could provide a permanent reconstructive solution to the patient by stimulating bone healing of the defect. In this paper the authors report on the feasibility and clinical results of using such a newly developed device for the repair of a large traumatic and therapy-resistant cranial bone defect. The patient had undergone numerous attempts at repair, in which established methods had been tried without success. A mosaic-designed device was manufactured and implanted, comprising interconnected ceramic tiles with a defined calcium phosphate composition. The clinical outcome 30 months after surgery revealed a restored cranial vault without postoperative complications. Computed tomography demonstrated signs of bone ingrowth. Examination with combined (18)F-fluoride PET and CT provided further evidence of bone healing of the cranial defect.

RET PLCγ phosphotyrosine binding domain regulates Ca2+ signaling and neocortical neuronal migration.

The receptor tyrosine kinase RET plays an essential role during embryogenesis in regulating cell proliferation, differentiation, and migration. Upon glial cell line-derived neurotrophic factor (GDNF) stimulation, RET can trigger multiple intracellular signaling pathways that in concert activate various downstream effectors. Here we report that the RET receptor induces calcium (Ca(2+)) signaling and regulates neocortical neuronal progenitor migration through the Phospholipase-C gamma (PLCγ) binding domain Tyr1015. This signaling cascade releases Ca(2+) from the endoplasmic reticulum through the inositol 1,4,5-trisphosphate receptor and stimulates phosphorylation of ERK1/2 and CaMKII. A point mutation at Tyr1015 on RET or small interfering RNA gene silencing of PLCγ block the GDNF-induced signaling cascade. Delivery of the RET mutation to neuronal progenitors in the embryonic ventricular zone using in utero electroporation reveal that Tyr1015 is necessary for GDNF-stimulated migration of neurons to the cortical plate. These findings demonstrate a novel RET mediated signaling pathway that elevates cytosolic Ca(2+) and modulates neuronal migration in the developing neocortex through the PLCγ binding domain Tyr1015.

Engineering the recruitment of phosphotyrosine binding domain-containing adaptor proteins reveals distinct roles for RET receptor-mediated cell survival.

The RET receptor tyrosine kinase is important for several different biological functions during development. The recruitment at the phosphorylated Tyr(1062) site in RET of a number of different phosphotyrosine binding (PTB) domain-containing adaptor proteins, including Shc and Frs2, plays a dominant role for the multiple different biological functions of the RET receptor during development, including stimulation of cell survival. Here, we demonstrate that a competitive recruitment of Shc as opposed to Frs2 mediates the survival signaling arising from RET activation. Based on results from a peptide array, we have genetically engineered the PTB domain binding site of RET to rewire its recruitment of the PTB proteins Shc and Frs2. An engineered RET that has a competitive interaction with Shc at the expense of Frs2, but not a RET receptor that only recruits Frs2, activates cell survival signaling pathways and is protective from cell death in neuronal SK-N-MC cells. Thus, cell type-specific functions involve a competitive recruitment of different PTB adaptor molecules by RET that activate selective signaling pathways.