Differentially regulated expression of growth differentiation factor 5 and bone morphogenetic protein 7 in articular cartilage and synovium in murine chronic arthritis: potential importance for cartilage breakdown and synovial hypertrophy

OBJECTIVE: To examine whether the endogenous expression of growth differentiation factor 5 (GDF-5) and bone morphogenetic protein 7 (BMP-7) is altered in the cartilage and synovium of human tumor necrosis factor alpha (TNFalpha)-transgenic (hTNFtg) mice with chronic arthritis, and to investigate the response of hTNFtg chondrocytes as well as fibroblast-like synoviocytes (FLS) to these morphogens in vitro. METHODS: Analyses were performed in hTNFtg mice with chronic destructive arthritis and in wild-type (WT) mice as controls. Expression of GDF-5 and BMP-7 in the articular cartilage and synovium was examined by real-time polymerase chain reaction and immunohistochemistry. Human TNFtg cartilage explants, chondrocytes, and FLS monolayer cultures were assessed for basal matrix biosynthesis as well as growth factor responsiveness, using (35)S-sulfate incorporation assays. In addition, the DNA content/cell proliferation rate was measured. RESULTS: The expression of GDF-5 and BMP-7 was decreased in articular cartilage from hTNFtg mice, whereas expression of both morphogens was increased in arthritic synovium from hTNFtg mice, as compared with the levels in WT controls. Isotope incorporation revealed a marked reduction of matrix synthesis in hTNFtg cartilage as well as a decrease in responsiveness to GDF-5 and BMP-7. The DNA content did not change in arthritic cartilage as compared with WT cartilage. In hTNFtg FLS, growth factor stimulation increased the rate of cell proliferation and the production of extracellular matrix. CONCLUSION: In this murine model of TNFalpha-mediated arthritis, the expression of GDF-5 and BMP-7 is regulated differentially in articular cartilage and synovium. In articular cartilage, the down-regulation of GDF-5 and BMP-7, which function to maintain matrix integrity, could potentially compromise tissue repair, whereas in synovium, the increased expression of GDF-5 and BMP-7 might contribute to synovial hypertrophy.     

Non‐invasive assessment of tryptophan fluorescence and confocal microscopy provide information on skin barrier repair dynamics beyond TEWL

The stratum corneum (SC) serves a primary function of skin barrier and understanding the kinetics of SC formation may provide great insight for skin diagnosis and evaluation of therapies. Besides trans‐epidermal water loss (TEWL), few methods have been characterized to assess skin barrier non‐invasively in vivo, particularly for dynamic measurements on the same specimen over time. The objective of this study was to characterize alternative non‐invasive methods to evaluate the dynamic processes involved in the recovery of normal human SC after total removal. TEWL, tryptophan fluorescence and reflectance confocal microscopy (RCM) were used to determine skin barrier function, cell turnover and epidermal morphology over a period of 10 days after total removal of the SC by tape stripping. The results show a biphasic recovery of TEWL over time, which contrasted with a linear increase of 2.3 μm/day in SC thickness. Tryptophan assessment of cell turnover also demonstrated a biphasic pattern attaining a maximum three to four times the levels of the control site 3 days after injury that slowly returned to baseline and displayed great correlation (R² > 0.95) to viable epidermis thickness that also achieved a maximum about 3 days after injury with an approximate increase of 55%. When plotting the change of TEWL versus SC thickness, a single exponential function is observed [Δ‐TEWL = 55 exp (?0.157×)] which contrasts with other proposed models. These methods were able to present rates for SC recovery processes beyond skin barrier (TEWL) that may provide new insights on kinetics of barrier formation for evaluation of skin conditions and treatments.     

Characterization and quantification of wound‐induced hair follicle neogenesis using in vivo confocal scanning laser microscopy

Background: In vivo confocal scanning laser microscopy (CSLM) is a recently developed non‐invasive technique for visualizing microscopic structures with the skin. CSLM has been used to characterize proliferative and inflammatory skin diseases, neoplastic skin lesions and pigmented lesions. Objective: Here, we assessed the ability of CSLM to evaluate the formation of neogenic hair follicles after a full‐thickness wound in mice. Methods: Full‐thickness wounds were made on the dorsal skin of 3‐week‐old mice. After scab detachment (SD), the number, width, length, space and volume of neogenic hair follicles were analyzed using CSLM. The results were compared with those from conventional methods, including staining for alkaline phosphatase (AP) and keratin 17 (K17) as well as histology. Results: Quantification of neogenic hair follicles using CSLM compared favorably with the results from direct measurements on isolated epidermal tissue after immunostaining for K17, a marker for the epithelial portion of new hair follicles. CSLM detected 89% of K17‐stained follicles. CSLM more accurately quantified the number of new follicles compared with AP staining, which detects the dermal portion of the new follicle. The width and length measurement from CSLM and histology were very close and correlated with each other. The minimum length of a neogenic hair follicle that could be detected by CSLM was 21 μm. The space between neogenic hair follicles was decreased in histological sections compared with CSLM. Conclusion: CSLM is an accurate and valuable method for counting and measuring neogenic hair follicles non‐invasively. CSLM produces images similar to histology in mice. Measurements of microstructures using CSLM more accurately reflect actual sizes as this technique avoids fixation artifacts. In vivo visualization of developing follicles with CSLM allows the detection of serial changes in hair follicle formation, thus conserving the numbers of mice required for studies and improving the detection of temporal changes in developing hair follicles.     

Preservation of motor programs in paraplegics as demonstrated by attempted and imagined foot movements

Execution and imagination of movement activate distinct neural circuits, partially overlapping in premotor and parietal areas, basal ganglia and cerebellum. Can long-term deafferented/deefferented patients still differentiate attempted from imagined movements? The attempted execution and motor imagery network of foot movements have been investigated in nine chronic complete spinal cord-injured (SCI) patients using fMRI. Thorough behavioral assessment showed that these patients were able to differentiate between attempted execution and motor imagery. Supporting the outcome of the behavioral assessment, fMRI disclosed specific patterns of activation for movement attempt and for motor imagery. Compared with motor execution data of healthy controls, movement attempt in SCI patients revealed reduced primary motor cortex activation at the group level, although activation was found in all single subjects with a high variability. Further comparisons with healthy subjects revealed that during attempt and motor imagery, SCI patients show enhanced activation and recruitment of additional regions in the parietal lobe and cerebellum that are important in sensorimotor integration. These findings reflect central plastic changes due to altered input and output and suggest that SCI patients may require additional cognitive resources to perform these tasks that may be one and the same phenomenon, or two versions of the same phenomenon, with quantitative differences between the two. Nevertheless, the retained integrity of movement attempt and motor imagery networks in SCI patients demonstrates that chronic paraplegics can still dispose of the full motor programs for foot movements and that therefore, attempted and imagined movements should be integrated in rehabilitative strategies.     

Clinical impact of oncoplastic surgery in a specialist breast practice

Background: Oncoplastic breast surgery is an integral and fundamental component of the clinical management of breast cancer. The aim of this study was to determine the proportion of oncoplastic and reconstructive breast cancer procedures undertaken within a specialist breast practice. Methods: An audit of breast‐related cancer procedures was undertaken for patients with early breast cancer between 1 January 2001 and 31 December 2005, treated at the Royal Adelaide Hospital and in private practice. The proportion of oncoplastic and breast reconstructive procedures was calculated to determine the clinical effects on a specialist breast‐surgical practice. Results: Breast cancer resection procedures accounted for 1514 of 2113 of operations (72%). Most of these (897 of 1514, 59.2%) were wide local excision or re‐excision procedures. Total breast reconstruction operations (i.e. autogenous tissue flaps, tissue expander/implant reconstructions) accounted for 251 procedures. Of these, 67 (26.7%) were carried out at the time of simple mastectomy. Contralateral breast procedures (i.e. reduction mammaplasty, mastopexy and augmentation) accounted for 138 procedures and nipple–areola reconstruction/tattoo accounted for 153 procedures. Oncoplastic procedures, such as skin‐sparing mastectomy, latissimus dorsi miniflap and therapeutic mammaplasty accounted for 57 of 599 procedures (9.5%). Breast reconstruction and oncoplastic operations accounted for 599 of 2113 procedures (28%). Conclusion: Specialist breast surgeons trained in breast reconstruction and oncoplastic techniques can expect a substantial proportion of their breast practice to include such operative procedures (28% in this series). Subspecialist training in breast surgery should incorporate experience in breast reconstructive and aesthetic surgery for trainees who wish to practise as specialist breast surgeons in the future.     

Comparison of volume displacement versus circumferential arm measurements for lymphoedema: implications for the SNAC trial

Background: The Royal Australasian College of Surgeons Sentinel Node versus Axillary Clearance trial is a randomized controlled trial comparing sentinel node biopsy with axillary clearance in breast cancer patients. Primary study end‐points include arm volume differences with time, which may indicate the development of lymphoedema. The RACS SNAC trial uses circumferential arm measurements in the estimation of arm volume. This study aimed to assess the accuracy of circumferential volume estimation in comparison with water displacement. Methods: Eighty‐seven women attending the breast clinic at the Women’s Health Centre, Royal Adelaide Hospital, were assessed by volumetric and circumferential arm measurements. Correlations between volume estimations and measurements were made, taking into account the width of measuring tape and body mass index. Results: There was a highly significant correlation between circumferential and volumetric arm measurements (Pearson’s correlation coefficient = 0.92, P < 0.0001), especially when using the narrow measuring tape. Correlation was best in the overweight BMI group (Pearson’s correlation coefficient = 0.94. P < 0.0001) and worst in the obese group (Pearson’s correlation coefficient = 0.79, P < 0.0001) but all relationships were statistically significant. Conclusion: Using a narrow tape, circumferential arm measurement is an appropriate method for assessing arm volume in the SNAC trial.     

Factors involved in selection of a career in surgery and orthopedics for medical students in Malawi

Aims

There is a critical shortage of Orthopedic Surgeons in Malawi as well as all countries in sub-Saharan Africa. To date, there is no published literature that has investigated surgical or Orthopedic career selection amongst African medical trainees. With the goal of facilitating recruitment into Surgery and Orthopedics in Malawi, we explored the key aspects of Malawian Medical Students'' choice of careers in surgical disciplines.

Methods

An on-line survey of all students in clinical years at the College of Medicine in Blantyre, Malawi was performed. The survey was anonymous and constructed de novo by a stringent process including Item Generation, Item reduction, Survey composition, Pre-testing, Assessment of Validity by a recognized survey expert, Pilot testing in on-line format by several Malawian Medical Students, and then formal survey testing.

Results

Surgery was the most popular specialty choice among the medical trainees (46%). General Surgery was the popular surgical specialty (27%), followed by Neurosurgery (22%) and Orthopedics (19%). The majority of students (67%) feared occupational exposure to HIV but this did not appear to be a factor in specialty choice (p=0.9). Students with Orthopedic mentors were significantly more likely to choose Orthopedics as their first choice surgical specialty (p = 0.01). Despite limited resources and surgeons in sub-Saharan Africa, surgical specialties are desirable career choices.

Conclusions

This is the first evaluation of factors involved in surgical or Orthopedic career selection in any African context. Future initiatives to improve exposure and mentorship in Orthopedics are fundamental to recruitment into the specialty.