Examining potential mechanisms of testicular fibrosis in Klinefelter Syndrome: A review of current understanding.

BACKGROUND: Men with Klinefelter Syndrome develop some degree of seminiferous tubule degeneration, hyalinization, and fibrosis by adulthood. However, the pathophysiology surrounding testicular fibrosis in Klinefelter Syndrome patients remains incompletely understood. OBJECTIVES: To perform a systematic review of literature studying the mechanisms of fibrosis initiation or propagation in Klinefelter Syndrome testes. MATERIALS/METHODS: PubMed was searched systematically for articles specific to Klinefelter Syndrome and the process of fibrosis. Articles that did not contain original data or specifically addressed the target material were excluded. Additional references were extracted when pertinent from the reference lists of included studies. RESULTS: Primary search yielded 139 articles for abstract review, which was narrowed to 16 for full-text review. Following full-text review, eight contained original data and met topic criteria, with one paper added from reference review for a total of nine papers. DISCUSSION: The date range for included papers was 1992-2022. The proposed mechanisms of fibrosis mainly were centered around the impact of altered Sertoli cells on germ cells, the hormonal impact on Leydig cells, the inflammation mediated by mast cells, or the fibrous extracellular matrix deposition by peritubular myoid cells. Additionally, discussions of the role of the altered microvasculature and the specific proteins involved in the blood-testis barrier or the seminiferous tubule architecture are reviewed. Recent papers have incorporated advanced sequencing and offer future directions for targeted gene expression analysis. Still, much of the published data consists solely of immunohistological assessment by age range, creating difficulties in extrapolating causality. CONCLUSION: The specific initiating factors of fibrosis of the seminiferous tubules and the propagation mechanisms unique to Klinefelter Syndrome remain incompletely understood with a relative paucity of data. Nonetheless, academic interest is increasing in this field as it may further elucidate the pathophysiology behind Klinefelter syndrome.

Urine leaks in children sustaining blunt renal trauma.

BACKGROUND: Few consensus statements exist to guide the timely diagnosis and management of urine leaks in children sustaining blunt renal trauma (BRT). The aims of this study were to characterize kidney injuries among children who sustain BRT, evaluate risk factors for urine leaks, and describe the negative impact of urinoma on patient outcomes and resource consumption. METHODS: A retrospective review was performed of 347 patients, younger than 19 years, who presented with BRT to a single American College of Surgeons-verified Level I Pediatric Trauma Center between 2005 and 2020. Frequency of and risk factors for urine leak after BRT were evaluated, and impact on patient outcomes and resource utilization were analyzed. RESULTS: In total, 44 (12.7%) patients developed urine leaks, which exclusively presented among injury Grade 3 (n = 5; 11.4%), Grade 4 (n = 27; 61.4%), and Grade 5 (n = 12; 27.3%). A minority of urine leaks (n = 20; 45.5%) were discovered on presenting CT scan but all within 3 days. Kidney-specific operative procedures (nephrectomy, cystoscopy with J/ureteral stent, percutaneous nephrostomy) were more common among urine leak patients (n = 17; 38.6%) compared with patients without urine leaks (n = 3; 1.0%; p = 0.001). Patients with urine leak had more frequent febrile episodes during hospital stay (n = 24; 54.5%; p = 0.001) and showed increased overall 90-day readmission rates (n = 14; 33.3%; p < 0.001). Independent risk factors that associated with urine leak were higher grade (odds ratio [OR], 7.9; 95% confidence interval [CI], 2.6-24.3; p < 0.001), upper-lateral quadrant injuries (OR, 2.9; 95% CI, 1.2-7.1; p = 0.02), and isolated BRT (OR, 2.6; 95% CI, 1.0-6.5; p = 0.04). CONCLUSION: In a large cohort of children sustaining BRT, urine leaks result in considerable morbidity, including more febrile episodes, greater 90-day readmission rates, and increased operative or image-guided procedures. This study is the first to examine the relationship between kidney quadrant injury and urine leaks. Higher grade (Grade 4-5) injury, upper lateral quadrant location, and isolated BRT were independently predictive of urine leaks. LEVEL OF EVIDENCE: Therapeutic/Care Management; Level III.

Effects of cone versus multi-leaf collimation on dosimetry and neurotoxicity in patients with small arteriovenous malformations treated by stereotactic radiosurgery.

PURPOSE/OBJECTIVE: Linear accelerator (LINAC) based stereotactic radiosurgery (SRS) for arteriovenous malformations (AVMs) is delivered with cone or multileaf collimators (MLCs), and favorable dosimetry is associated with reduced radionecrosis in normal brain tissue. This study aims to determine whether cones or MLCs has better dosimetric characteristics, to predict differences in toxicity. METHODS: All patients treated for AVMs using LINAC SRS from 2003-2017 were examined retrospectively. Demographic data, volumes of normal tissue exposed to 12Gy (V12Gy[cc]) and 4Gy (V4Gy[cc]), maximal dose, and dose gradient were analyzed. Univariate and multivariate analyses were used to evaluate relationships between collimator type, dosimetric parameters, and toxicity. Propensity score matching was used to adjust for AVM size. RESULTS: Compared to MLC, cones were independently associated with reduced V12Gy[cc] after propensity score matching (p=0.008) and reduced neurotoxicity (p=0.016). Higher V12Gy[cc] (p=0.0008) and V4Gy[cc] (p=0.002) were associated with increased neurotoxicity. CONCLUSIONS: Treating AVMs with cone-based SRS over MLC-based SRS may improve dosimetry and reduce toxicities.

Stereotactic Radiosurgery and Hypofractionated Stereotactic Radiotherapy for Nonfunctioning Pituitary Adenoma.

Objectives Hypofractionated stereotactic radiotherapy (HSRT) in two to five fractions may offer patients with large nonfunctioning pituitary adenomas (NFPAs) with chiasm involvement a safe and effective treatment over a single week. However, little has been reported regarding this novel approach. Design We compared the feasibility, outcomes, and toxicity of single-fraction stereotactic radiosurgery and HSRT. Setting This study was conducted at a tertiary academic referral center. Participants After approval by the institutional review board, we performed a retrospective cohort study of patients treated at our institution with stereotactic radiosurgery (SRS) and HSRT for NFPA. Selection for SRS or HSRT was based on clinicopathologic factors including tumor size and cavernous sinus invasion at the discretion of the treating physician. Main Outcome Measures Local control, endocrinopathy, and radiation-associated toxicity were evaluated by binary logistic regression and Cox's proportional hazards regression. Results A total of 45 patients with mean follow-up of 5 years were enrolled including 26 patients treated by HSRT with mean follow-up of 3 years and 19 patients treated by SRS with median follow-up of 6 years. Clinicopathologic characteristics were balanced between cohorts. Local failure at last follow-up was 5% in the SRS cohort and 8% in the HSRT cohort, and rates of post-SRS endocrinopathy were similar between each cohort. Late complications including radionecrosis, visual deficit, and secondary malignancy were minimal in either cohort. Conclusions HSRT is an appropriate treatment strategy for patients with NFPAs, particularly for optic pathway preservation in the setting of large tumors with chiasm involvement. Further studies are needed to optimize fractionated approaches and patient selection.

Changes in FXR1 expression after Chemotherapy for Rhabdomyosarcoma.

BACKGROUND: Rhabdomyosarcoma (RMS) arises from abnormal muscle development. We reported previously that Fragile-X-Related 1 (FXR1), essential to normal myogenesis, was highly expressed in RMS relative to other embryonal tumors. This current study explored FXR1 expression across RMS disease characteristics and treatment response. METHODS: RMS patients ≤18 years (1980-2019; n = 152) were categorized according to tumor histology, PAX/FOXO1 translocation, and vital status. FXR1 protein expression was compared before and after chemotherapy. Impact of FXR1 expression on relapse-free (RFS) and overall survival (OS) was analyzed. RESULTS: FXR1 was most intensely expressed in the cytosol of undifferentiated rhabdomyoblasts. At diagnosis, FXR1 expression was ubiquitous and strong across all disease characteristics and foremost associated with worse RFS in translocation-positive patients (p = 0.0411). Among embryonal and translocation-negative RMS, survivors showed a significantly greater decrease in FXR1 expression after chemotherapy (p < 0.001) compared to decedents (p = 0.8). In contrast, alveolar and translocation-positive RMS specimens showed insignificant changes in FXR1 expression across therapy. As expected, alveolar histology, translocation presence, stage, and clinical group associated with worse survival. CONCLUSIONS: FXR1 was expressed strongly across RMS specimens at diagnosis regardless of disease or patient characteristics, and particularly in undifferentiated cells. Reduction in FXR1 expression after chemotherapy associated with improved survival for embryonal and translocation-negative RMS patients.

Obesity is Associated with Longer Survival Independent of Sarcopenia and Myosteatosis in Metastatic and/or Castrate-Resistant Prostate Cancer.

PURPOSE: Obesity (body mass index 30 kg/m2 or greater) is associated with better overall survival in metastatic prostate cancer. Conversely, low muscle mass (sarcopenia) and low muscle radiodensity (myosteatosis) are associated with worse overall survival in many cancers. This study seeks to evaluate the relationship of sarcopenia, myosteatosis and obesity with overall survival in men with metastatic or castrate-resistant prostate cancer. MATERIALS AND METHODS: Retrospective analysis of men with metastatic or castrate-resistant prostate cancer and computerized tomography of abdomen/pelvis presenting to the Vanderbilt Comprehensive Prostate Cancer Clinic from 2012 to 2017 was performed. Demographic, pathological and survival data were described, with sarcopenia and myosteatosis determined from abdominal skeletal muscle area and skeletal muscle radiodensity, respectively. Kaplan-Meier curves and log-rank tests estimated the effect of body composition on survival. Multivariable Cox proportional hazard models were performed adjusting for age, Charlson comorbidity index, race and clinical stage. ANOVA was used to compare obese and nonobese men with and without sarcopenia or myosteatosis. RESULTS: Of 182 men accrued, 37.4% were obese, 53.3% sarcopenic and 59.3% myosteatotic. Over a median followup of 33.9 months, body mass index was associated with reduced mortality (HR 0.93, p=0.02), as was visceral adiposity (HR 0.99, p=0.003). Men with high body mass index without sarcopenia/myosteatosis lived significantly longer than men with high body mass index with sarcopenia/myosteatosis or normal body mass index men (F[3,91]=4.03, p=0.01). CONCLUSIONS: Both high body mass index and visceral adiposity in metastatic or castrate-resistant prostate cancer are associated with reduced mortality, independent of sarcopenia and myosteatosis. Therefore, routine clinical workup should include calculation of body mass index and measurement of waist circumference. Morphometric analysis of computerized tomography imaging can identify patients at risk for poor prognosis.

Investigating the reaction and substrate preference of indole-3-acetaldehyde dehydrogenase from the plant pathogen Pseudomonas syringae PtoDC3000.

Aldehyde dehydrogenases (ALDHs) catalyze the conversion of various aliphatic and aromatic aldehydes into corresponding carboxylic acids. Traditionally considered as housekeeping enzymes, new biochemical roles are being identified for members of ALDH family. Recent work showed that AldA from the plant pathogen Pseudomonas syringae strain PtoDC3000 (PtoDC3000) functions as an indole-3-acetaldehyde dehydrogenase for the synthesis of indole-3-acetic acid (IAA). IAA produced by AldA allows the pathogen to suppress salicylic acid-mediated defenses in the model plant Arabidopsis thaliana. Here we present a biochemical and structural analysis of the AldA indole-3-acetaldehyde dehydrogenase from PtoDC3000. Site-directed mutants targeting the catalytic residues Cys302 and Glu267 resulted in a loss of enzymatic activity. The X-ray crystal structure of the catalytically inactive AldA C302A mutant in complex with IAA and NAD+ showed the cofactor adopting a conformation that differs from the previously reported structure of AldA. These structures suggest that NAD+ undergoes a conformational change during the AldA reaction mechanism similar to that reported for human ALDH. Site-directed mutagenesis of the IAA binding site indicates that changes in the active site surface reduces AldA activity; however, substitution of Phe169 with a tryptophan altered the substrate selectivity of the mutant to prefer octanal. The present study highlights the inherent biochemical versatility of members of the ALDH enzyme superfamily in P. syringae.

Conservative management of bladder endometriosis with acute renal failure.

Endometriosis involving the bladder is rare, but generally has a severe presentation with prominent lower urinary tract symptoms and can progress to renal failure. As endometriosis has a significant effect on quality of life and fertility, treatment plans must be centered on the patient's symptoms, expectations, and priorities. We present a case of a 37-year-old African American female with advanced bladder endometriosis and consequent renal failure, who desired to avoid extensive surgery and maintain her fertility. This case highlights the importance of shared decision making in balancing disease management with patient autonomy.

Outcomes of stereotactic radiosurgery and hypofractionated stereotactic radiotherapy for refractory Cushing's disease.

PURPOSE: Hypofractionated stereotactic radiotherapy (HSRT) for refractory Cushing's disease may offer a condensed treatment schedule for patients with large tumors abutting the optic chiasm unsuitable for stereotactic radiosurgery (SRS). To-date only four patients have been treated by HSRT in the published literature. We investigated the feasibility, toxicity, and efficacy of HSRT compared to SRS. METHODS: After approval, we retrospectively evaluated patients treated at our institution for refractory Cushing's disease with SRS or HSRT. Study outcomes included biochemical control, time to biochemical control, local control, and late complications. Binary logistic regression and Cox proportional hazards regression evaluated predictors of outcomes. RESULTS: Patients treated with SRS (n = 9) and HSRT (n = 9) were enrolled with median follow-up of 3.4 years. Clinicopathologic details were balanced between the cohorts. Local control was 100% in both cohorts. Time to biochemical control was 6.6. and 9.5 months in the SRS and HSRT cohorts, respectively (p = 0.6258). Two patients in each cohort required salvage bilateral adrenalectomy. Late complications including secondary malignancy, radionecrosis, cranial nerve neuropathy, and optic pathway injury were minimal for either cohort. CONCLUSIONS: HSRT is an appropriate treatment approach for refractory Cushing's disease, particularly for patients with large tumors abutting the optic apparatus. Prospective studies are needed to validate these findings and identify factors suggesting optimal fractionation approaches.

Fibrosis, low vascularity, and fewer slow fibers after rotator-cuff injury.

INTRODUCTION: Rotator-cuff injury (RCI) represents 50% of shoulder injuries, and prevalence increases with age. Even with successful tendon repair, muscle and joint function may not return. METHODS: To explore the dysfunction, supraspinatus and ipsilateral deltoid (control) muscles were biopsied during arthroscopic RCI repair for pair-wise histological and protein-expression studies. RESULTS: Supraspinatus showed fiber atrophy (P < 0.0001), fibrosis (by Sirius Red, P = 0.05), reduced vascular density (P < 0.001), and a lower proportion of slow fibers (P < 0.0001) compared with the ipsilateral control muscle. There were also higher levels of atrogin-1 (P = 0.05), vascular endothelial growth factor (VEGF, P < 0.01), and dystrophin (P < 0.008, relative to fiber diameter) versus control. CONCLUSIONS: Adaptive changes in vascular endothelial growth factor and dystrophin were likely associated with reduced vascular supply, fatigue resistance, and fibrosis, accompanied by disuse atrophy from mechanical unloading of supraspinatus after tendon tear. Treatment to promote growth and vascularity in atrophic supraspinatus muscle may help improve functional outcome after surgical repair. Muscle Nerve 55: 715-726, 2017.