A Novel Model of Urinary Tract Differentiation,Tissue Regeneration,and Disease: Reprogramming Human Prostate and Bladder Cells into Induced Pluripotent Stem Cells

Background

Primary culture and animal and cell-line models of prostate and bladder development have limitations in describing human biology, and novel strategies that describe the full spectrum of differentiation from foetal through to ageing tissue are required. Recent advances in biology demonstrate that direct reprogramming of somatic cells into pluripotent embryonic stem cell (ESC)-like cells is possible. These cells, termed induced pluripotent stem cells (iPSCs), could theoretically generate adult prostate and bladder tissue, providing an alternative strategy to study differentiation.

Objective

To generate human iPSCs derived from normal, ageing, human prostate (Pro-iPSC), and urinary tract (UT-iPSC) tissue and to assess their capacity for lineage-directed differentiation.

Design, setting, and participants

Prostate and urinary tract stroma were transduced with POU class 5 homeobox 1 (POU5F1; formerly OCT4), SRY (sex determining region Y)-box 2 (SOX2), Kruppel-like factor 4 (gut) (KLF4), and v-myc myelocytomatosis viral oncogene homolog (avian) (MYC, formerly C-MYC) genes to generate iPSCs.

Outcome measurements and statistical analysis

The potential for differentiation into prostate and bladder lineages was compared with classical skin-derived iPSCs. The student t test was used.

Results and limitations

Successful reprogramming of prostate tissue into Pro-iPSCs and bladder and ureter into UT-iPSCs was demonstrated by characteristic ESC morphology, marker expression, and functional pluripotency in generating all three germ-layer lineages. In contrast to conventional skin-derived iPSCs, Pro-iPSCs showed a vastly increased ability to generate prostate epithelial-specific differentiation, as characterised by androgen receptor and prostate-specific antigen induction. Similarly, UT-iPSCs were shown to be more efficient than skin-derived iPSCs in undergoing bladder differentiation as demonstrated by expression of urothelial-specific markers: uroplakins, claudins, and cytokeratin; and stromal smooth muscle markers: α-smooth-muscle actin, calponin, and desmin. These disparities are likely to represent epigenetic differences between individual iPSC lines and highlight the importance of organ-specific iPSCs for tissue-specific studies.

Conclusions

IPSCs provide an exciting new model to characterise mechanisms regulating prostate and bladder differentiation and to develop novel approaches to disease modelling. Regeneration of bladder cells also provides an exceptional opportunity for translational tissue engineering.     

Healing of osteotomy sites applying either piezosurgery or two conventional saw blades: a pilot study in rabbits

Purpose

The purpose of this study was to compare bone healing of experimental osteotomies applying either piezosurgery or two different oscillating saw blades in a rabbit model.

Methods

The 16 rabbits were randomly assigned into four groups to comply with observation periods of one, two, three and five weeks. In all animals, four osteotomy lines were performed on the left and right nasal bone using a conventional saw blade, a novel saw blade and piezosurgery.

Results

All three osteotomy techniques revealed an advanced gap healing starting after one week. The most pronounced new bone formation took place between two and three weeks, whereby piezoelectric surgery revealed a tendency to faster bone formation and remodelling. Yet, there were no significant differences between the three modalities.

Conclusions

The use of a novel as well as the piezoelectric bone-cutting instrument revealed advanced bone healing with a favourable surgical performance compared to a traditional saw.     

Assessment and management of chronic pain in patients with stable total hip arthroplasty

Total hip arthroplasty (THA) is one of the most successful operations that can restore function and relieve pain. Although a majority of the patients achieve significant pain relief after THA, there are a number of patients that develop chronic pain for unknown reasons. A literature search was performed looking for chronic pain after total hip arthroplasty and stable THA. Major causes of chronic pain include aseptic loosening or infection. However, there is a subset of patients with a stable THA that present with chronic pain which can have several aetiologies. These include soft tissue, bony, neurological, vascular and psychological causes. Essential for successful treatment is the ability to make the correct diagnosis. Thus therapy may be either non-operative or operative. In addition, diagnosis and management often may require multidisciplinary approaches to successfully alleviate chronic pain in these patients with a stable prosthesis.     

Laparoendoscopic single-site (LESS) varicocelectomy with reusable components: comparison with the conventional laparoscopic technique

Background

This study aimed to compare laparoendoscopic single-site varicocelectomy (LESSV) with multiport laparoscopic varicocelectomy (MLV) in terms of intraoperative parameters and postoperative outcomes.

Methods

A retrospective case–control study investigated 10 male adolescents and 89 adults who underwent either LESSV or MLV at the authors’ center. The reusable X-Cone single port was inserted transumbilically. A 5-mm 30° telescope was used together with a straight and a prebent laparoscopic instrument. The MLV procedure was performed using two 5-mm ports and one 10-mm port.

Results

Between January 2009 and November 2012, 20 patients underwent LESSV and 79 patients underwent MLV. The demographic data were comparable between the two groups. The mean operating time was 59.1 ± 15.5 min for LESSV and 51.2 ± 14.4 min for MLV (P = 0.04). In the LESSV group, no conversion to MLV was necessary. The hospital stay was 1.6 ± 0.7 days in the LESSV group versus 1.8 ± 0.5 days in the MLV group (P = 0.17). The postoperative pain scores did differ between the two groups. By day 2, significantly more patients in the LESSV group than in the MLV group fully recovered their normal physical activity (P = 0.02). Comparison of pre- and postoperative values showed relief of testicular pain and improvement of semen parameters for the majority of the patients. The overall incidence of complications was distributed equally between the two groups as follows: paresthesia of the upper thigh (8 %), wound infection (5 %), epididymitis (3 %) and hydrocele (4 %). All the patients in the LESSV group were fully satisfied with their cosmetic results compared with only 76 % of the patients in the MLV group (P = 0.01).

Conclusions

The LESSV procedure performed with the reusable X-Cone is as safe and efficient as MLV. After LESSV, the parameters measuring postoperative patient satisfaction are significantly improved. Given its reusable components, including prebent laparoscopic instruments, the X-Cone platform is a cost-effective alternative to disposable or homemade single ports.     

Clinical and radiographical results after double flip button stabilization of acute grade III and IV acromioclavicular joint separations

Introduction

Persistent horizontal instability after acute acromioclavicular (AC) joint separation may provoke unsatisfactory results of conservative treatment. Hypothesis: the arthroscopically assisted double flip button stabilization of acute horizontally unstable grade III and IV AC joint disruptions results in full functional restoration and stable radiological reposition.

Materials

21 patients treated for an acute grade III or IV AC joint separation were enrolled. Clinical assessment at least 2-year postoperative included the constant score (CS) and the simple shoulder test. A panorama stress view, bilateral axial view and an AC view were obtained for radiographic evaluation.

Results

19 individuals (mean 37 years; 17 men) with 16 Rockwood type III and 3 type IV injuries were available for examination 24–51 months postoperatively. The mean CS was 90.2 points (SD 6.5) with no statistically significant difference between CS and age-adjusted normative values. The mean Simple Shoulder Test scored 11.5 points (range 8–12). Loss of reduction of more than 2 mm in the coronal plane stress views was present in 6 patients (32 %) with no associated loss of functional outcome. Two of four reported complications in four patients were treated surgically (one open revision with graft augmentation for coracoid implant break out, one arthroscopic capsular release for persistent glenohumeral stiffness).

Conclusion

Arthroscopically assisted double flip button stabilization for acute grade III and IV AC joint separation restores fully horizontal stability and age-expected shoulder function, resulting in high patient satisfaction, despite a loss of reduction observed radiographically in approximately one-third of patients.

Level of evidence

IV.     

Prognostic Value of Disseminated Tumor Cells in the Bone Marrow of Patients with Operable Primary Breast Cancer: A Long-term Follow-up Study

Background

Detection of disseminated tumor cells (DTC) in primary breast cancer (BC) patients’ bone marrow (BM) seems to be a surrogate marker of tumor spread and an independent prognostic factor for disease-free and overall survival.

Methods

Here we present the largest single-center cohort of patients (n = 1378) with the longest observation time (median 82.0 months). Immunocytochemical staining was performed using murine monoclonal antibody 2E11 with the avidin–biotin complex technique.

Results

At primary surgery, 49 % of patients showed MUC-1 positive cells inside their BM. Patients without BM DTC had significantly more often T1-tumors (P = 0.007) with less often affected axillary lymph nodes (P < 0.001). We observed a significantly higher incidence of distant metastases in DTC positive patients (P < 0.001). This leads to a reduced disease-free survival (P < 0.0001). Furthermore, in DTC positive patients there was a higher mortality rate and, accordingly, a reduced overall survival (P < 0.0001).

Conclusions

Due to the presence of BM DTC, patients with a clinically poorer outcome can be identified at primary surgery. We therefore suggest that DTC analysis can be used as a prognostic factor and monitoring tool in clinical trials. Future study concepts relating to DTC should aim at identification of BC patients who may profit from adjuvant systemic therapy.     

Reflux-Associated Oxygen Desaturations: Usefulness in Diagnosing Reflux-Related Respiratory Symptoms

Background

Current diagnostic techniques establishing gastroesophageal reflux disease as the underlying cause in patients with respiratory symptoms are poor. Our aim was to provide additional support to our prior studies suggesting that the association between reflux events and oxygen desaturations may be a useful discriminatory test in patients presenting with primary respiratory symptoms suspected of having gastroesophageal reflux as the etiology.

Methods

Thirty-seven patients with respiratory symptoms, 26 with typical symptoms, and 40 control subjects underwent simultaneous 24-h impedance–pH and pulse oximetry monitoring. Eight patients returned for post-fundoplication studies.

Results

The median number (interquartile range) of distal reflux events associated with oxygen desaturation was greater in patients with respiratory symptoms (17 (9–23)) than those with typical symptoms (7 (4–11, p?<?0.001)) or control subjects (3 (2–6, p?<?0.001)). A similar relationship was found for the number of proximal reflux-associated desaturations. Repeat study in seven post-fundoplication patients showed marked improvement, with reflux-associated desaturations approaching those of control subjects in five patients; 20 (9–20) distal preoperative versus 3 (0–5, p?=?0.06) postoperative; similar results were identified proximally.

Conclusions

These data provide further proof that reflux-associated oxygen desaturations may discriminate patients presenting with primary respiratory symptoms as being due to reflux and may respond to antireflux surgery.     

Are Mammographic Changes in the Tumor Bed More Pronounced After Intraoperative Radiotherapy for Breast Cancer? Subgroup Analysis from a Randomized Trial (TARGIT‐A)

Intraoperative radiotherapy (IORT) with low‐energy x‐rays is increasingly used in breast‐conserving therapy (BCT). Previous non‐randomized studies have observed mammographic changes in the tumor bed to be more pronounced after IORT. The purpose of this study was to reassess the postoperative changes in a randomized single‐center subgroup of patients from a multicenter trial (TARGIT‐A). In this subgroup (n = 48) 27 patients received BCT with IORT, 21 patients had BCT with standard whole‐breast radiotherapy serving as controls. Overall 258 postoperative mammograms (median follow‐up 4.3 years, range 3–8) were retrospectively evaluated by two radiologists in consensus focusing on changes in the tumor bed. Fat necroses showed to be significantly more frequent (56% versus 24%) and larger (8.7 versus 1.6 sq cm, median) after IORT than those in controls. Scar calcifications were also significantly more frequent after IORT (63% versus 19%). The high incidence of large fat necroses in our study confirms previous study findings. However, the overall higher incidence of calcifications in the tumor bed after IORT represents a new finding, requiring further attention.