Therapeutic role of bone marrow mesenchymal stem cells in diabetic neuronal alternations of rat hippocampus.

BACKGROUND: As the hippocampus is the main brain region for many forms of learning and memory functions and is acutely sensitive to blood glucose changes, diabetes mellitus, which is a serious metabolic disease, is often accompanied by learning and memory deficits. Through scientific literatures, mesenchymal stem cells (MSCs) promote functional recovery in rats with traumatic brain injury, so the present work was conducted to study MSCs as a possible treatment for the diabetic neuronal degeneration and functional impairment of rat hippocampus. MATERIALS AND METHODS: It was carried out using male albino rats: non-diabetic control groups (4, 8, 12 weeks) (n = 15), diabetic groups by i.v. injection of streptozotocin for (4, 8, 12 weeks) (n = 15) and MSCs treatment to diabetic groups for (8, 12 weeks) (n = 10). Hippocampal learning and memory functions were assessed by the Morris Water Maze test and its results were statistically analysed. The rat hippocampal regions (CA1 and CA3) were subjected to histological, ultrastructural examination and morphometrical analyse of pyramidal neurons. RESULTS: Neurons of the diabetic groups showed disturbed function and architecture; shrunken hyperchromatic nuclei and vacuolated eosinophilic cytoplasm (apoptotic changes) also MSCs treatment improved hippocampal learning and memory functions plus its architectural changes; increasing populations and normal regular distribution. CONCLUSIONS: It can be concluded that diabetic hippocampal neuronal alternations and functional impairment can be ameliorated by MSCs treatment.

Yield of Image-Guided Needle Biopsy for Infectious Discitis: A Systematic Review and Meta-Analysis.

BACKGROUND: Image-guided biopsy is routinely conducted in patients with suspected discitis, though the sensitivity reported in the literature ranges widely. PURPOSE: We applied a systematic review and meta-analysis to estimate the yield of image-guided biopsy for infectious discitis. DATA SOURCES: We performed a literature search of 4 data bases: PubMed, Cochrane CENTRAL Register of Controlled Trials, Embase.com, and Scopus from data base inception to March 2016. STUDY SELECTION: A screen of 1814 articles identified 88 potentially relevant articles. Data were extracted for 33 articles, which were eligible if they were peer-reviewed publications of patients with clinical suspicion of discitis who underwent image-guided biopsy. DATA ANALYSIS: Patients with positive cultures out of total image-guided biopsy procedures were pooled to estimate yield with 95% confidence intervals. Hypothesis testing was performed with an inverse variance method after logit transformation. DATA SYNTHESIS: Image-guided biopsy has a yield of approximately 48% (793/1763), which is significantly lower than the open surgical biopsy yield of 76% (152/201; P < .01). Biopsy in patients with prior antibiotic exposure had a yield of 32% (106/346), which was not significantly different from the yield of 43% (336/813; P = .08) in patients without prior antibiotic exposure. LIMITATIONS: The conclusions of this meta-analysis are primarily limited by the heterogeneity of the included studies. CONCLUSIONS: Image-guided biopsy has a moderate yield for the diagnosis of infectious discitis, which is significantly lower than the yield of open surgical biopsy. This yield is not significantly affected by prior antibiotic use.

Metabolic alterations: a biomarker for radiation-induced normal brain injury-an MR spectroscopy study.

PURPOSE: To assess if interval changes in metabolic status in normal cerebral tissue after radiation therapy (RT) can be detected by 2D CSI (chemical shift imaging) proton spectroscopy. MATERIALS AND METHODS: Eleven patients with primary brain tumors undergoing cranial radiation therapy (RT) were included. 2D-CSI MRS was performed before, during, and after the course of RT with the following parameters: TE/TR 144/1500 ms, field of view (FOV) 24, thickness 10 mm, matrix 16 x 16. The metabolic ratios choline/creatine (Cho/Cr), N-acetylaspartate (NAA)/Cr, and NAA/Cho in normal brain tissue were calculated. RESULTS: NAA/Cr and Cho/Cr were significantly decreased at week 3 during RT and at 1 month and 6 months after RT compared to values prior to RT (P < 0.01). The NAA/Cr ratio decreased by -0.19 +/- 0.05 (mean +/- standard error [SE]) at week 3 of RT, -0.14 +/- 0.06 at the last week of RT, -0.14 +/- 0.05 at 1 month after RT, and -0.30 +/- 0.08 at 6 months after RT compared to the pre-RT value of 1.43 +/- 0.04. The Cho/Cr ratio decreased by -0.27 +/- 0.05 at week 3 of RT, -0.11 +/- 0.05 at the last week of RT, -0.26 +/- 0.05 at 1 month after RT and -0.25 +/- 0.07 at 6 months after RT from the pre-RT value of 1.29 +/- 0.03. Changes in Cho/Cr were correlated with the interaction of the radiation dose and dose-volume at week 3 of RT, during the last week of RT (P < 0.005), and at 1 month after RT (P = 0.017). CONCLUSION: The results of this study suggest that MRS can detect early metabolic changes in normal irradiated brain tissue.

Safety of the limited open technique of bone-transfixing threaded-pin placement for external fixation of distal radial fractures: a cadaver study.

OBJECTIVE: To examine the safety of threaded-pin placement for fixation of distal radial fractures using a limited open approach. DESIGN: A cadaver study. METHODS: Four-millimetre Schanz threaded pins were inserted into the radius and 3-mm screw pins into the second metacarpal of 20 cadaver arms. Each threaded pin was inserted in the dorsoradial oblique plane through a limited open, 5- to 10-mm longitudinal incision. Open exploration of the threaded-pin sites was then carried out. OUTCOME MEASURES: Injury to nerves, muscles and tendons and the proximity of these structures to the threaded pins. RESULTS: There were no injuries to the extensor tendons, superficial radial or lateral antebrachial nerves of the forearm, or to the soft tissues overlying the metacarpal. The lateral antebrachial nerve was the closest nerve to the radial pins and a branch of the superficial radial nerve was closest to the metacarpal pins. The superficial radial nerve was not close to the radial pins. CONCLUSION: Limited open threaded-pin fixation of distal radial fractures in the dorsolateral plane appears to be safe.

Accuracy of intraoperative assessment of acetabular prosthesis placement.

Anteversion and vertical tilt of the acetabular prostheses in 50 consecutive total hip arthroplasties were prospectively evaluated during surgery (by the surgeon, using an alignment guide) and radiographically (calculated). From postoperative standardized radiographs vertical tilt was measured directly and anteversion was calculated. The mean error of vertical tilt was 5 degrees (range, 0 degrees - 20 degrees). The mean error of version was 9 degrees (range, 0 degrees - 24 degrees). The reliability of prosthesis placement in a predetermined zone was examined. Although the surgeons believed that all 50 cups were inside this zone, radiographic measurements revealed that 21 of the cups were actually outside. It is concluded that vertical tilt can be reasonably assessed during surgery. Anteversion, however, cannot be accurately assessed during surgery, despite use of the alignment guide.

Radiographic calculation of anteversion in acetabular prostheses.

The position of the acetabular prosthesis is critical for preventing dislocation following total hip arthroplasty. The reliability of a mathematical model for radiographically calculated acetabular cup version was examined. A porous-coated anatomic acetabular prosthesis was mounted in a mold. Anteroposterior radiographs were taken with the cup in five different positions of anteversion. These were reviewed by five orthopaedic surgeons, and measurements were taken from each radiograph. From these measurements, the mathematically derived degree of version was calculated. The results were examined for accuracy and intraobserver reliability. It was concluded that intraobserver reliability was very good and that the accuracy was within a clinically acceptable range. This technique could be useful in studying the "safe zone" for acetabular prostheses.

Absence of cis-acting transposition immunity with Tn7.

It is possible in two steps to insert into the plasmid RP4 two copies of the transposon Tn7. This was demonstrated using a wild-type Tn7 in the first step, and a Tn7 derivative (carrying an additional marker), in the second step. The two successive transpositions occurred with the same polarity and frequency. The genetic structures of the resulting plasmids, predicted from the phenotypes of the bacterial host, were confirmed by direct analysis of the plasmid DNAs. Thus, the phenomenon of cis-acting transposition immunity, described with Tn1 or Tn3, does not take place in the case of Tn7.