Bone and non-contractile soft tissue changes following open kinetic chain resistance training and testosterone treatment in spinal cord injury: an exploratory study.

Twenty men with spinal cord injury (SCI) were randomized into two 16-week intervention groups receiving testosterone treatment (TT) or TT combined with resistance training (TT + RT). TT + RT appears to hold the potential to reverse or slow down bone loss following SCI if provided over a longer period. INTRODUCTION: Persons with SCI experience bone loss below the level of injury. The combined effects of resistance training and TT on bone quality following SCI remain unknown. METHODS: Men with SCI were randomized into 16-week treatments receiving TT or TT + RT. Magnetic resonance imaging (MRI) of the right lower extremity before participation and post-intervention was used to visualize the proximal, middle, and distal femoral shaft, the quadriceps tendon, and the intermuscular fascia of the quadriceps. For the TT + RT group, MRI microarchitecture techniques were utilized to elucidate trabecular changes around the knee. Individual mixed models were used to estimate effect sizes. RESULTS: Twenty participants completed the pilot trial. A small effect for yellow marrow in the distal femur was indicated as increases following TT and decreases following TT + RT were observed. Another small effect was observed as the TT + RT group displayed greater increases in intermuscular fascia length than the TT arm. Distal femur trabecular changes for the TT + RT group were generally small in effect (decreased trabecular thickness variability, spacing, and spacing variability; increased network area). Medium effects were generally observed in the proximal tibia (increased plate width, trabecular thickness, and network area; decreased trabecular spacing and spacing variability). CONCLUSIONS: This pilot suggests longer TT + RT interventions may be a viable rehabilitation technique to combat bone loss following SCI. CLINICAL TRIAL REGISTRATION: Registered with clinicaltrials.gov : NCT01652040 (07/27/2012).

Strong Size Dependency on the Carrier and Photon Dynamics in InGaN/GaN Single Nanowalls Determined Using Photoluminescence and Ultrafast Transient Absorption Spectroscopy.

Here, we have demonstrated strong size dependency of quasi-equilibrium and nonequilibrium carrier and photon dynamics in InGaN/GaN single nanowalls using photoluminescence and transient absorption spectroscopy. We demonstrate that two-dimensional carrier confinement, strain relaxation, and modified density of states lead to a reduced Stokes shift, smaller full width at half-maxima, increased exciton binding energy, and reduced nonradiative recombination. The ultrafast transient spectroscopy shows that carrier capture is a two-step process dominated by optical phonons and carrier-carrier scattering in succession. The carrier capture is a strongly size-dependent process and becomes slower due to modulation of the density of available states for progressively decreasing nanowall sizes. The slowest process is the electron-hole recombination, which is also extremely size-dependent and the rate increases by almost an order of magnitude in comparison to that of quantum-well structures. Electron-hole wave function overlap and modified density of states are among the key aspects in determining all the properties of these structures.

Bone architecture adaptations after spinal cord injury: impact of long-term vibration of a constrained lower limb.

SUMMARY: This study examined the effect of a controlled dose of vibration upon bone density and architecture in people with spinal cord injury (who eventually develop severe osteoporosis). Very sensitive computed tomography (CT) imaging revealed no effect of vibration after 12 months, but other doses of vibration may still be useful to test. INTRODUCTION: The purposes of this report were to determine the effect of a controlled dose of vibratory mechanical input upon individual trabecular bone regions in people with chronic spinal cord injury (SCI) and to examine the longitudinal bone architecture changes in both the acute and chronic state of SCI. METHODS: Participants with SCI received unilateral vibration of the constrained lower limb segment while sitting in a wheelchair (0.6g, 30 Hz, 20 min, three times weekly). The opposite limb served as a control. Bone mineral density (BMD) and trabecular micro-architecture were measured with high-resolution multi-detector CT. For comparison, one participant was studied from the acute (0.14 year) to the chronic state (2.7 years). RESULTS: Twelve months of vibration training did not yield adaptations of BMD or trabecular micro-architecture for the distal tibia or the distal femur. BMD and trabecular network length continued to decline at several distal femur sub-regions, contrary to previous reports suggesting a "steady state" of bone in chronic SCI. In the participant followed from acute to chronic SCI, BMD and architecture decline varied systematically across different anatomical segments of the tibia and femur. CONCLUSIONS: This study supports that vibration training, using this study's dose parameters, is not an effective anti-osteoporosis intervention for people with chronic SCI. Using a high-spatial-resolution CT methodology and segmental analysis, we illustrate novel longitudinal changes in bone that occur after spinal cord injury.

Use of local anesthesia in transrectal ultrasound guided prostatic biopsy.

Transrectal ultrasound (TRUS) guided biopsy of the prostate is the gold standard for detecting prostate cancer. Intraprostatic administration of local anesthesia significantly decreases pain during prostatic biopsy. Transrectal ultrasound guided intraprostatic lidocaine administration along with intrarectally lidocaine gel is a new local anesthesia technique for prostatic biopsy. It was a randomized prospective, comparative, interventional type of the study. A total of 60 patients of age over 55 years included in the study among them 30 patients with transrectal lidocaine gel was in Group I and 30 patients with intraprostatic lidocaine injection with intra rectal gel were in Group II. The mean age was almost identically distributed between the two groups (p=0.668). About 47% of patients in Group I exhibited hard prostate on digital rectal examination (DRE), 33.3% single nodule and 20% multinodule compared to 33.3% of patients in Group II had hard prostate, 26.7% single nodule and 40% multinodule (p=0.236). The mean serum prostate specific antigen (PSA) was significantly higher in Group II than that in Group I (36.7±9.2 vs. 7.5±5.8ng/ml; p=0.007). The mean pain intensity during biopsy was almost two times higher in Group I than in Group II (p<0.001). The present study concludes that the intraprostatic lidocaine injection along with intra rectal lidocaine gel is less painful method and can be considered in all patients undergoing transrectal ultrasound guided prostate biopsy.

Carbohydrate response element-binding protein (ChREBP) plays a pivotal role in beta cell glucotoxicity.

AIMS/HYPOTHESIS: This study was aimed at the elucidation of the pathogenesis of glucotoxicity, i.e. the mechanism whereby hyperglycaemia damages pancreatic beta cells. The identification of pathways in the process may help identify targets for beta cell-protective therapy. Carbohydrate response element-binding protein (ChREBP), a transcription factor that regulates the expression of multiple hyperglycaemia-induced genes, is produced in abundance in pancreatic beta cells. We hypothesise that ChREBP plays a pivotal role in mediating beta cell glucotoxicity. METHODS: We assessed the role of ChREBP in glucotoxicity in 832/13 beta cells, isolated mouse islets and human pancreas tissue sections using multiple complementary approaches under control and high-glucose-challenge conditions as well as in adeno-associated virus-induced beta cell-specific overexpression of Chrebp (also known as Mlxipl) in mice. RESULTS: Under both in vitro and in vivo conditions, ChREBP activates downstream target genes, including fatty acid synthase and thioredoxin-interacting protein, leading to lipid accumulation, increased oxidative stress, reduced insulin gene transcription/secretion and enhanced caspase activity and apoptosis, processes that collectively define glucotoxicity. Immunoreactive ChREBP is enriched in the nucleuses of beta cells in pancreatic tissue sections from diabetic individuals compared with non-diabetic individuals. Finally, we demonstrate that induced beta cell-specific Chrebp overexpression is sufficient to phenocopy the glucotoxicity manifestations of hyperglycaemia in mice in vivo. CONCLUSIONS/INTERPRETATION: These data indicate that ChREBP is a key transcription factor that mediates many of the hyperglycaemia-induced activations in a gene expression programme that underlies beta cell glucotoxicity at the molecular, cellular and whole animal levels.

High dose compressive loads attenuate bone mineral loss in humans with spinal cord injury.

UNLABELLED: People with spinal cord injury (SCI) lose bone and muscle integrity after their injury. Early doses of stress, applied through electrically induced muscle contractions, preserved bone density at high-risk sites. Appropriately prescribed stress early after the injury may be an important consideration to prevent bone loss after SCI. INTRODUCTION: Skeletal muscle force can deliver high compressive loads to bones of people with spinal cord injury (SCI). The effective osteogenic dose of load for the distal femur, a chief site of fracture, is unknown. The purpose of this study is to compare three doses of bone compressive loads at the distal femur in individuals with complete SCI who receive a novel stand training intervention. METHODS: Seven participants performed unilateral quadriceps stimulation in supported stance [150% body weight (BW) compressive load-"High Dose" while opposite leg received 40% BW-"Low Dose"]. Five participants stood passively without applying quadriceps electrical stimulation to either leg (40% BW load-"Low Dose"). Fifteen participants performed no standing (0% BW load-"Untrained") and 14 individuals without SCI provided normative data. Participants underwent bone mineral density (BMD) assessment between one and six times over a 3-year training protocol. RESULTS: BMD for the High Dose group significantly exceeded BMD for both the Low Dose and the Untrained groups (p < 0.05). No significant difference existed between the Low Dose and Untrained groups (p > 0.05), indicating that BMD for participants performing passive stance did not differ from individuals who performed no standing. High-resolution CT imaging of one High Dose participant revealed 86% higher BMD and 67% higher trabecular width in the High Dose limb. CONCLUSION: Over 3 years of training, 150% BW compressive load in upright stance significantly attenuated BMD decline when compared to passive standing or to no standing. High-resolution CT indicated that trabecular architecture was preserved by the 150% BW dose of load.

Relationship of Serum Uric Acid Level with Acute Ischemic Stroke: A Single-Center, Hospital-Based Study from Bangladesh.

The role of uric acid as a risk factor for cerebrovascular disease, particularly acute ischemic stroke, is controversial and there is little information about this in our setting. This cross-sectional study was conducted at the departments of Medicine and Neurology of a tertiary hospital in Bangladesh over one year, from January 2018 to December 2018, to estimate serum uric acid (SUA) levels and assess its risk factor potential in patients with acute ischemic stroke. Forty-five patients with acute ischemic stroke were enrolled and a similar number of age and sex-matched healthy individuals were recruited for comparison. All known risk factors for stroke were searched and SUA levels were measured. SUA was higher (6.66±2.33 vs. 5.23±1.81 mg/dL; p=0.002) and hyperuricemia was more frequent (64.4% vs. 24.4%, p<0.001) in stroke patients in comparison to the controls. Hypertension was more frequent among stroke patients. In multivariate analysis, hyperuricemia [OR 4.51 (95% CI 1.67-12.16; p<0.05)] and HTN [OR 6.31 (95% CI 2.26-17.61; p<0.001)] were found to be independent risk factors of acute ischemic stroke. The stroke and control groups had no differences in age, sex, residence, education, monthly income, occupation, fasting plasma glucose, triglyceride and high-density lipoprotein cholesterol levels. Total cholesterol and low-density lipoprotein cholesterol levels were higher in the stroke patients. SUA may be used as a marker for increased risk of ischemic stroke. However, larger-scale studies are needed to get more insight into our findings.

Prevalence of multidrug-resistant tuberculosis among category II pulmonary tuberculosis patients.

BACKGROUND & OBJECTIVES: Multidrug-resistant tuberculosis (MDR-TB) has emerged as a significant global health concern. The most important risk factor for the development of MDR-TB is previous anti-tuberculosis therapy. Category II pulmonary TB includes those patients who had failed previous TB treatment, relapsed after treatment, or defaulted during previous treatment. We carried out this study to ascertain the prevalence of MDR-TB among category II pulmonary TB patients. METHODS: This was a cross-sectional, descriptive study involving category II pulmonary TB patients diagnosed between 2005 and 2008. All sputum-positive category II TB cases were subjected to mycobacterial culture and drug-susceptibility testing (DST). MDR-TB was defined as TB caused by bacilli showing resistance to at least isoniazid and rifampicin. RESULTS: A total of 196 cases of sputum-positive category II pulmonary tuberculosis patients were included. Of these, 40 patients (20.4%) had MDR-TB. The mean age of MDR-TB patients was 33.25 ± 12.04 yr; 9 patients (22.5%) were female. Thirty six patients showed resistance to rifampicin and isoniazid; while 4 patients showed resistance to rifampicin, isoniazid and streptomycin. The prevalence of MDR-TB among category-II pulmonary tuberculosis patients was 20.4 per cent. INTERPRETATION & CONCLUSIONS: The prevalence of MDR-TB in category II TB patients was significant. However, nation-wide and State-wide representative data on prevalence of MDR-TB are lacking. We stress the importance of continuous monitoring of drug resistance trends, in order to assess the efficacy of current interventions and their impact on the TB epidemic.

Three-body nonmesonic weak decay of the (Lambda)12C hypernucleus.

We have measured the branching ratio of the three-body process in the nonmesonic weak decay of Lambda12C to be 0.29+/-0.13. This result was obtained by reproducing the nucleon and the nucleon pair yields introducing a measured final state interaction. At the same time, we have determined the absolute decay widths, Gamma(n) and Gamma(p), along with Gamma2N, whose relative ratio has been a long-standing puzzle. Including the three-body process, we have successfully reproduced the nucleon energy distribution, the coincidence two-nucleon angular correlation, and the momentum sum distribution simultaneously.

Kinetics of growth and multi substrate degradation by an indigenous mixed microbial culture isolated from a wastewater treatment plant in Guwahati, India.

An indigenous mixed culture of microorganisms, isolated from a sewage treatment plant, was investigated for its potential to simultaneously degrade phenol and m-cresol during its growth in batch shake flasks. 2(2) full factorial designs with the two substrates as the factors, at two different levels and two different initial concentration ranges, were employed to carry out the biodegradation experiments. For complete utilisation of phenol and m-cresol, the culture took a minimum duration of 21 hrs at their low concentration of 100 mg/L each, and a maximum duration of 187 hrs at high concentration of 600 mg/L each in the multisubstrate system. The biodegradation results also showed that the presence of phenol in low concentration range (100-300 mg/L did not inhibit m-cresol biodegradation; on the other hand, presence of m-cresol inhibited phenol biodegradation by the culture. Moreover, irrespective of the concentrations used, phenol was degraded preferentially and earlier than m-cresol. During the culture growth, a lag phase was observed above a combined concentration of 500 mg/L i.e., 200 mg/L m-cresol and 300 mg/L of phenol and above). Statistical analysis of the specific growth rate of the culture in the multisubstrate system was also performed in the form of ANOVA and Student 't' test, which gave good interpretation in terms of main and interaction effects of the substrates.

Forgotten, Encrusted Ureteral Stents: Removal - Multimodal Endourologic Approach.

Ureteral stent placement is a common procedure in urologic practice. Forgotten, encrusted D/J stents represent a difficult problem for urologists. The major complications are infection, impaired renal function, migration, encrustation, stone formation and multiple fragmentation of stent. A consensus on the best therapeutic approach is still lacking. Here we present our experience with endoscopic management of this challenging problem and discuss the multimodal endourologic approaches for treating forgotten, encrusted ureteral stents. In this prospective observational study 29 patients (17 males and 12 females), age ranges from 19 to 57 years with 35 (23 unilateral and 6 bilateral) encrusted ureteral stents, indwelling for 5 to 78 months were treated in the Department of Urology, Dhaka Medical College Hospital (DMCH), Dhaka, Bangladesh from January 2011 to December 2015. All patients were evaluated by urine culture and sensitivity, renal function. Stent encrustation and the associated stone burden were estimated by plain radiograph. Treatment decisions were made based on the clinical presentation, degree of encrustation, stone burden and image findings. Patients were followed up to 06 months. The main indications for stenting were pyelolithotomy, ureterolithotomy, ureteroneocystostomy, URS and pyeloplasty. In kidney, mild encrustation was common (48.3%) moderate encrustation (27.6%) was less common; where as in ureter and urinary bladder, moderate encrustation was common (72.4% and 44.8%). Over three-quarters 22(75.9%) of the patients underwent extracorporeal shockwave lithotripsy (ESWL) and 10(34.5%) percuteneousnephrostomy preoperatively. Retrograde ureteroscopy with intracorporeal lithotripsy (URS & ICPL) was done in 29 cases and cystolitholapaxy (CLL) in 16(55%) cases. Cystolithotomy & PCNL was rarely done. The mean number of procedures was 2.8 (range: 1-7). Using these multimodal approaches, all stents and associated stones were eventually removed with minor complications. Nine patients developed haematuria, 5 urosepsis and 4 both haematuria & urosepsis. Multimodal endourologic approaches can safely remove forgotten, encrusted D/J stents, if treatment is tailored to the volume of encrustation and associated stone. Imaging evaluation and documentation of negative urine culture are imperative prior to any attempt to remove the stent.

Efficacy and Safety of Mycobacterium indicus pranii as an adjunct therapy in Category II pulmonary tuberculosis in a randomized trial.

Prolonged treatment of tuberculosis (TB) often leads to poor compliance, default and relapse, converting primary TB patients into category II TB (Cat IITB) cases, many of whom may convert to multi-drug resistant TB (MDR-TB). We have evaluated the immunotherapeutic potential of Mycobacterium indicus pranii (MIP) as an adjunct to Anti-Tubercular Treatment (ATT) in Cat II pulmonary TB (PTB) patients in a prospective, randomized, double blind, placebo controlled, multicentric clinical trial. 890 sputum smear positive Cat II PTB patients were randomized to receive either six intra-dermal injections (2 + 4) of heat-killed MIP at a dose of 5 × 108 bacilli or placebo once in 2 weeks for 2 months. Sputum smear and culture examinations were performed at different time points. MIP was safe with no adverse effects. While sputum smear conversion did not show any statistically significant difference, significantly higher number of patients (67.1%) in the MIP group achieved sputum culture conversion at fourth week compared to the placebo (57%) group (p = 0.0002), suggesting a role of MIP in clearance of the bacilli. Since live bacteria are the major contributors for sustained incidence of TB, the potential of MIP in clearance of the bacilli has far reaching implications in controlling the spread of the disease.

Predictors of development and outcome in patients with acute respiratory distress syndrome due to tuberculosis.

OBJECTIVE: To study the predictors of development and determinants of outcome in patients with acute respiratory distress syndrome (ARDS) due to tuberculosis (TB). METHODS: Retrospective case-control study of demographic, clinical and laboratory data of hospitalised adult patients with active TB. RESULTS: Of 2733 TB patients treated during 1980-2003, 29 (1.06%; 1.21 patients/year; mean age 31.6 +/- 10.9 years; 16 males) developed ARDS (cases). Seven had pulmonary TB and 22 had miliary TB (MTB); 298 (mean age 32.0 +/- 14.2 years; 110 males) who did not develop ARDS constituted controls. Presence of MTB (OR 4.6, 95%CI 1.2-17.8; P = 0.02), duration of illness beyond 30 days at presentation (OR 177.9, 95%CI 39-811.7; P < 0.001), absolute lymphocyte count < 1625/ mm3 (OR 4.5, 95%CI 1.1-19.3; P = 0.04) and serum ALT > 100 IU (OR 15.7, 95%CI 3.0-81.1, P < 0.001) were independent predictors of ARDS development. Twelve cases died (41.4%). Patients with APACHE II score >18; those with APACHE II score <18 in the presence of hyponatraemia and PaO2/FIO2 ratio <108.5 were likely to die. CONCLUSIONS: In patients with TB, prolonged illness, MTB, absolute lymphocytopaenia and elevated ALT are independently associated with ARDS development. APACHE II score, serum sodium and PaO2/FIO2 ratio are determinants of outcome.

Mechanics of the ankle and subtalar joints revealed through a 3D quasi-static stress MRI technique.

A technique to study the three-dimensional (3D) mechanical characteristics of the ankle and of the subtalar joints in vivo and in vitro is described. The technique uses an MR scanner compatible 3D positioning and loading linkage to load the hindfoot with precise loads while the foot is being scanned. 3D image processing algorithms are used to derive from the acquired MR images bone morphology, hindfoot architecture, and joint kinematics. The technique was employed to study these properties both in vitro and in vivo. The ankle and subtler joint motion and the changes in architecture produced in response to an inversion load and an anterior drawer load were evaluated. The technique was shown to provide reliable measures of bone morphology. The left-to-right variations in bone morphology were less than 5%. The left-to-right variations in unloaded hindfoot architecture parameters were less than 10%, and these properties were only slightly affected by inversion and anterior drawer loads. Inversion and anterior drawer loads produced motion both at the ankle and at the subtalar joint. In addition, high degree of coupling, primarily of internal rotation with inversion, was observed both at the ankle and at the subtalar joint. The in vitro motion produced in response to inversion and anterior drawer load was greater than the in vivo motion. Finally, external motion, measured directly across the ankle complex, produced in response to load was much greater than the bone movements measured through the 3D stress MRI technique indicating the significant effect of soft tissue and skin interference.

Reversal of subclinical adrenal insufficiency through antituberculosis treatment in TB patients: a longitudinal follow up.

BACKGROUND & OBJECTIVE: Subclinical adrenal insufficiency has been shown to occur in patients with tuberculosis. Whether this insufficiency can be reversed with therapy and on long-term follow up, is not known. We studied the effect of antituberculosis treatment (ATT) with respect to reversal of the adrenal insufficiency, as assessed by response to standard dose adrenocorticotropin (ACTH) stimulation test in TB patients. METHODS: One hundred and five HIV-negative tuberculosis patients were studied. Of these, 72 patients had pulmonary and 33 had extrapulmonary forms of the disease. Baseline (pre-treatment) standard-dose ACTH stimulation test was done on all the subjects, following which, they were put on standard antituberculosis therapy, depending on the type of disease and were followed up for a period of 30 months. ACTH stimulation tests were performed at follow up, every 6 months. RESULTS: Baseline (pre-treatment) standard-dose ACTH stimulation test revealed an impaired response in 52 of 105 patients (49.5%). At 6 months, the percentage of responders had increased to 71 per cent with a gradual increasing trend noted thereafter. At 24 months, 31 of the 32 patients (97%) who were followed up demonstrated a normal response to ACTH stimulation. The percentage of responders was comparable in both pulmonary [21 of 22 patients (95%)] and extrapulmonary TB [10 of 10 patients (100%)] groups at follow up. INTERPRETATION & CONCLUSION: Our study shows that nearly half of patients with active tuberculosis had a subclinical adrenal insufficiency indicated by an impaired response to ACTH stimulation test. This insufficiency reverse with therapy in most patients on long-term follow up.

Contraceptive practices and awareness of emergency contraception in educated working women.

BACKGROUND: Regular contraceptive use and emergency contraception are tools to prevent pregnancies. AIMS: This study was designed to investigate knowledge and use of contraceptive methods and awareness of emergency contraception among women working in the hospital. SETTINGS: Educated workingwomen in a medical college hospital. DESIGN: Cross-sectional study. MATERIALS AND METHODS: The study was carried out among women belonging to three categories: staff nurses, ministerial staff and others. Married as well as unmarried employees in the reproductive age group were interviewed. A pretested mixed questionnaire containing open as well as closed ended questions was administered. The women were asked questions concerning knowledge and use of contraceptive methods and awareness of emergency or postcoital contraception. RESULTS: Of the 284 employees 258 women consented for the interview. All the subjects were literate and majority (97.2%) had an urban background. Of the 190 married women, 154 (81.1%) practiced contraception, among them (73.3%) were regular users. Eighty respondents underwent abortions of which 46 had spontaneous and 34 had induced abortions. Among the available contraceptive methods, condom was the most popular method in 89 (57.8%) followed by Copper T in 38 women (24.7%). The use of hormonal contraception was very low 2.6%. Print and electronic media were the common source of public awareness in 149 subjects (57.7%). Twenty-nine women (11.2%) were aware and only three women used emergency contraception. CONCLUSIONS: A high percentage of females in this literate workingwomen population used contraception; however, the awareness of emergency contraception was low.

Leech bite: a rare gynecologic emergency.

Vaginal bleeding as the result of a leech bite is a rare occurrence. We report 2 cases of vaginal bleeding in young girls that resulted from a leech bite and required treatment. Clinical presentation and management for young girls is described. Health professionals working in rural areas where leech infestation is common should be aware that children are at risk for leech bites in the genital region; a high index of suspicion is of great help to make an early diagnosis and ensure prompt treatment.

Digital topological analysis of in vivo magnetic resonance microimages of trabecular bone reveals structural implications of osteoporosis.

Osteoporosis is a disease characterized by bone volume loss and architectural deterioration. The majority of work aimed at evaluating the structural implications of the disease has been performed based on stereologic analysis of histomorphometric sections. Only recently noninvasive imaging methods have emerged that provide sufficient resolution to resolve individual trabeculae. In this article, we apply digital topological analysis (DTA) to magnetic resonance microimages (mu-MRI) of the radius obtained at 137 x 137 x 350 microm3 voxel size in a cohort of 79 women of widely varying bone mineral density (BMD) and vertebral deformity status. DTA is a new method that allows unambiguous determination of the three-dimensional (3D) topology of each voxel in a trabecular bone network. The analysis involves generation of a bone volume fraction map, which is subjected to subvoxel processing to alleviate partial volume blurring, followed by thresholding and skeletonization. The skeletonized images contain only surfaces, profiles, curves, and their mutual junctions as the remnants of trabecular plates and rods after skeletonization. DTA parameters were compared with integral BMD in the lumbar spine and femur as well as MR-derived bone volume fraction (BV/TV). Vertebral deformities were determined based on sagittal MRIs of the spine with a semiautomatic method and the number of deformities counted after threshold setting. DTA structural indices were found the strongest discriminators of subjects with deformities from those without deformities. Subjects with deformities (n = 29) had lower topological surface (SURF) density (p < 0.0005) and surface-to-curve ratio (SCR; a measure of the ratio of platelike to rodlike trabeculae; p < 0.0005) than those without. Profile interior (PI) density, a measure of intact trabecular rods, was also lower in the deformity group (p < 0.0001). These data provide the first in vivo evidence for the structural implications inherent in postmenopausal osteoporosis accompanying bone loss, that is, the conversion of trabecular plates to rods and disruption of rods due to repeated osteoclastic resorption.

Reproducibility and error sources of micro-MRI-based trabecular bone structural parameters of the distal radius and tibia.

The mechanical competence of trabecular bone is significantly determined, next to material density, by its three-dimensional (3D) structure. Recent advances in micromagnetic resonance imaging (micro-MRI) acquisition and processing techniques allow the 3D trabecular structure to be analyzed in vivo at peripheral sites such as the distal radius and tibia. The practicality of micro-MRI-based noninvasive virtual bone biopsy (VBB) for longitudinal studies of patients hinges on the reproducibility of the derived structural parameters, which largely determine the size of the effect that can be detected at a given power and significance level. In this paper, the reproducibility of micro-MRI-derived trabecular bone structure measures was examined by performing repeat studies in six healthy subjects in whom the distal aspects of the radius and tibia were scanned with a 3D spin-echo sequence at 137 x 137 x 410 microm3 voxel size. Bone volume fraction (BV/TV) and digital topological analysis (DTA) structural parameters including the topological bone surface-to-curve ratio (SCR) and topological erosion index (TEI) were evaluated after subjecting the raw images to a cascade of processing steps. The average coefficient of variation was 4-7% and was comparable for the two anatomic sites and for all parameters measured. The reliability expressed in terms of the intraclass correlation coefficient ranged from 0.95 to 0.97 in the radius and 0.68 to 0.92 in the tibia. Error analysis based on simulations suggests involuntary patient motion, primarily rotation, to be the chief source of imprecision, followed by failure to accurately match the analysis volumes in repeat studies.

Blood coagulation and fibrinolysis in haemorrhagic stroke.

Studies of 11 patients with haemorrhagic stroke revealed no significant change in kaolin cephalin clotting time, prothrombin time, thrombin time, PF 3 availability, platelet count and factor V and VIII during the first week. Plasma fibrinogen was significantly increased while factors VII + X were decreased (borderline significance). Prolongation of plasma recalcification time and decrease in heparin tolerance reached borderline significance. There was moderate, but significant, increase in serum antithrombin activity and plasma (euglobulin fraction) fibrinolytic activity.