Is the iliolumbar ligament a reliable identifier of the L5 vertebra in lumbosacral transitional anomalies?

Objective

Sufficiently sized studies to determine the value of the iliolumbar ligament (ILL) as an identifier of the L5 vertebra in cases of a lumbosacral transitional vertebra (LSTV) are lacking.

Methods

Seventy-one of 770 patients with LSTV (case group) and 62 of 611 subjects without LSTV with confirmed L5 level were included. Two independent radiologists using coronal MR images documented the level(s) of origin of the ILL. The interobserver agreement was analysed using weighted kappa/kappa (wκ/κ) and a Fischer’s exact test to assess the value of the ILL as an identifier of the L5 vertebra.

Results

The ILL identified the L5 vertebra by originating solely from L5 in 95 % of the controls; additional origins were observed in 5 %. In the case group, the ILL was able to identify the L5 vertebra by originating solely from L5 in 25–38 %. Partial origin from L5, including origins from other vertebra was observed in 39–59 % and no origin from L5 at all in 15–23 % (wκ?=?0.69). Both readers agreed that an ILL was always present and its origin always involved the last lumbar vertebra.

Conclusion

The level of the origin of the ILL is unreliable for identification of the L5 vertebra in the setting of an LSTV or segmentation anomalies.

Key Points

? The origin of the ILL is evaluated in subjects with an LSTV. ? The origin of the ILL is anatomically highly variable in LSTV. ? The ILL is not a reliable landmark of the L5 vertebra in LSTV.     

Reduction of hepatic and adipose tissue glucocorticoid receptor expression with antisense oligonucleotides improves hyperglycemia and hyperlipidemia in diabetic rodents without causing systemic glucocorticoid antagonism

Glucocorticoids (GCs) increase hepatic gluconeogenesis and play an important role in the regulation of hepatic glucose output. Whereas systemic GC inhibition can alleviate hyperglycemia in rodents and humans, it results in adrenal insufficiency and stimulation of the hypothalamic-pituitary-adrenal axis. In the present study, we used optimized antisense oligonucleotides (ASOs) to cause selective reduction of the glucocorticoid receptor (GCCR) in liver and white adipose tissue (WAT) and evaluated the resultant changes in glucose and lipid metabolism in several rodent models of diabetes. Treatment of ob/ob mice with GCCR ASOs for 4 weeks resulted in approximately 75 and approximately 40% reduction in GCCR mRNA expression in liver and WAT, respectively. This was accompanied by approximately 65% decrease in fed and approximately 30% decrease in fasted glucose levels, a 60% decrease in plasma insulin concentration, and approximately 20 and 35% decrease in plasma resistin and tumor necrosis factor-alpha levels, respectively. Furthermore, GCCR ASO reduced hepatic glucose production and inhibited hepatic gluconeogenesis in liver slices from basal and dexamethasone-treated animals. In db/db mice, a similar reduction in GCCR expression caused approximately 40% decrease in fed and fasted glucose levels and approximately 50% reduction in plasma triglycerides. In ZDF and high-fat diet-fed streptozotocin-treated (HFD-STZ) rats, GCCR ASO treatment caused approximately 60% reduction in GCCR expression in the liver and WAT, which was accompanied by a 40-70% decrease in fasted glucose levels and a robust reduction in plasma triglyceride, cholesterol, and free fatty acids. No change in circulating corticosterone levels was seen in any model after GCCR ASO treatment. To further demonstrate that GCCR ASO does not cause systemic GC antagonism, normal Sprague-Dawley rats were challenged with dexamethasone after treating with GCCR ASO. Dexamethasone increased the expression of GC-responsive genes such as PEPCK in the liver and decreased circulating lymphocytes. GCCR ASO treatment completely inhibited the increase in dexamethasone-induced PEPCK expression in the liver without causing any change in the dexamethasone-induced lymphopenia. These studies demonstrate that tissue-selective GCCR antagonism with ASOs may be a viable therapeutic strategy for the treatment of the metabolic syndrome.     

Aortic root dilatation may alter the dimensions of the valve leaflets

Objective: Valve-sparing surgery can be used in patients with dilated aortic roots and aortic insufficiency (AI) but has not become a common practice, in part because the spared valve may be incompetent. Our goal was to study how the dimensions of the aortic root and leaflets have changed in such patients. Methods: Fourteen patients with dilated aortic root and AI were examined by transesophageal echocardiography. The annulus diameter, sinotubular junction (STJ) diameter, sinus height, leaflet free-edge length, and leaflet height were measured. Correlations among these dimensions and with the AI grades were explored. Measurements were also made in 19 normal human aortic valves from silicone molds. Results: There was no evident change in the average diameter of the annulus between the normal valves and those in the dilated aortic roots. The STJ diameter was obviously increased in the dilated aortic roots; the aortic sinuses also appeared to be taller and the leaflets larger than normal. The leaflet free-edge length, the leaflet height, and the sinus height were found to increase with the dilated STJ diameter. The degree of AI was not found to correlate well with any of the dimensions measured. Conclusions: The dimensions of the leaflets may change parallel to aortic root dilatation with AI. Therefore, during valve sparing, it may be necessary to correct both the dilatation of the root and the leaflet free-edge length to achieve a competent valve.     

Fluoropolymer coated Dacron or polytetrafluoroethylene for femoropopliteal bypass grafting: a multicentre trial

Background: This trial was designed to compare graft patency between expanded polytetrafluoroethylene (PTFE) and fluoro­polymer coated Dacron for femoropopliteal bypass in patients in whom saphenous vein was unavailable. Methods: A multicentre prospective trial randomized 129 patients (74 men, 55 women) who underwent femoropopliteal bypass using either a PTFE or fluoropolymer coated Dacron graft. The indication for operation was disabling claudication in 68 (52.7%) and critical limb ischaemia in 61 (47.3%) patients. Distal anastomosis was above the knee in 76 (58.9%) and below the knee in 53 (41.1%) patients. Results: Primary patency at 6, 12 and 24 months was 71%, 56% and 47% for PTFE and 50%, 36% and 36% for fluoropolymer coated Dacron (P = 0.002), respectively. Secondary patency at 6, 12 and 24 months was 77%, 60% and 48% for PTFE and 66%, 49% and 46% for fluoropolymer coated Dacron (P = 0.13), respectively. The superior primary patency of PTFE over fluoropolymer coated Dacron was most evident in patients with poor prognostic indicators for graft survival: critical limb ischaemia (P = 0.001); below‐knee anastomosis (P = 0.01); and smaller (6 mm) diameter grafts (P = 0.002). Graft thrombosis developed in the first month in 22 of 61 (36%) patients receiving fluoropolymer coated grafts compared to six of 68 (8.8%) patients receiving PTFE, which accounts for the difference in primary patency. Successful thrombectomy in 10 of the 22 fluoropolymer coated grafts resulted in similar secondary patency. Conclusion: Polytetrafluoroethylene has superior primary patency and similar secondary patency to fluoropolymer coated Dacron. These results support the preferential use of PTFE in patients with critical limb ischaemia, especially when a below‐knee distal anastomosis and smaller diameter graft is required.     

Intracrystalline proteins and urolithiasis: a synchrotron X-ray diffraction study of calcium oxalate monohydrate.

The existence of intracrystalline proteins and amino acids in calcium oxalate monohydrate was demonstrated by X-ray synchrotron diffraction studies. Their presence has implications for the destruction of calcium oxalate crystals formed in the urinary tract and the prevention of kidney stones. INTRODUCTION: Although proteins are present in human kidney stones, their role in stone pathogenesis remains unknown. This investigation aimed to characterize the nature of the relationship between the organic and mineral phases in calcium oxalate monohydrate (COM) crystals grown in human urine and in aqueous solutions of proteins and amino acids to clarify the function of proteins in urolithiasis. METHODS: COM crystals were grown in human urine and in aqueous solutions containing either human prothrombin (PT), Tamm-Horsfall glycoprotein (THG), aspartic acid (Asp), aspartic acid dimer (AspAsp), glutamic acid (Glu), glutamic acid dimer (GluGlu), or gamma-carboxyglutamic acid (Gla). Controls consisted of COM crystals precipitated from pure inorganic solutions or from human urine that had been ultrafiltered to remove macromolecules. Synchrotron X-ray diffraction with Rietveld whole-pattern peak fitting and profile analysis was used to determine nonuniform crystal strain and crystallite size in polycrystalline samples. RESULTS: Crystals precipitated from ultrafiltered urine had lower nonuniform strain than those grown in urine or in aqueous PT solution. Nonuniform strain was much lower in crystals grown in distilled water or in the presence of THG. For the amino acids, the highest nonuniform strain was exhibited by crystals grown in Gla solution, followed by Glu. Crystallite size was inversely related to nonuniform strain, with the effect being significantly less for amino acids than for macromolecules. CONCLUSIONS: Selected proteins and amino acids associated with COM crystals are intracrystalline. Although their incorporation into the mineral bulk would be expected to affect the rate of crystal growth, they also have the potential to influence the phagocytosis and intracellular destruction of any crystals nucleated and trapped within the renal collecting system. Crystals impregnated with protein would be more susceptible to digestion by cellular proteases, which would provide access to the crystal core, thereby facilitating further proteolytic degradation and mineral dissolution. We therefore propose that intracrystalline proteins may constitute a natural form of defense against renal stone formation.     

Acute chest pain with normal coronary angiogram: role of contrast-enhanced multidetector computed tomography in the differential diagnosis between myocarditis and myocardial infarction

OBJECTIVE: To evaluate the accuracy of delayed-enhanced multidetector computed tomography (MSCT) for differentiating between myocarditis and myocardial infarction in patients with normal x-ray coronary angiography. METHODS: Twelve consecutive patients referred for acute chest pain and normal coronary arteries on x-ray coronary angiography were involved in this study. Delayed-enhanced MSCT and postgadolinium delayed-enhanced magnetic resonance imaging (MRI) examinations were performed within 36 hours and 4 days, respectively, after patient admission. Comparison between delayed-enhanced MSCT and MRI was performed by 3 independent blinded observers in term of final diagnosis, number of involved segments, and transmural extent. RESULTS: Final diagnosis between myocarditis and myocardial infarction was identical for delayed-enhanced MSCT and MRI with a significant agreement for number of involved segments and transmural extension. Interobserver reproducibility was good for both techniques. CONCLUSIONS: We demonstrated that delayed-enhanced MSCT allows differentiation between myocardial infarction and myocarditis with the same accuracy at acute phase compared with MRI.     

Intestinal graft versus native liver cytokine expression in a rat model of intestinal transplantation with and without donor-specific cell augmentation

BACKGROUND: Immunomodulatory strategies such as donor-specific bone marrow or blood transfusions have been used to promote engraftment after intestinal transplants. We previously showed that delivery of donor antigen via the portal vein can effectively reduce the rate of intestinal graft rejection. The purpose of our current study was to investigate the impact of donor-specific cell augmentation (blood versus bone marrow) via the portal vein on cytokine expression in intestinal grafts versus native livers. MATERIAL AND METHODS: We performed heterotopic small intestinal transplants between male Brown-Norway (donor) and female Lewis (recipient) rats. We studied 10 groups according to the type of donor-specific cell augmentation and the use and dose of immunosuppressive therapy. For cell augmentation, donor-specific blood or bone marrow was transfused via the donor portal vein immediately before graft implantation. For immunosuppression, tacrolimus was used post-transplant at a high or low dose. Control rats received neither immunosuppression nor cell augmentation. Tissue samples for histological assessment were obtained at designated time points. RNA was extracted from intestinal graft and native liver biopsies for cytokine measurements (IL-1 alpha, IL-1 beta, IL-2, IL-4, IL-5, IL-6, IFN-gamma, TNF-alpha, and TNF-beta). Chimerism levels were determined using Q-PCR analysis. RESULTS: Without concurrent immunosuppression, neither portal donor-specific blood nor bone marrow transfusion reduced the rate of rejection. With immunosuppression, outcome was significantly better after portal donor-specific blood (versus bone marrow) transfusion. Irrespective of the type of donor-specific cell augmentation, severe rejection caused strong cytokine expression in the grafts of IL-1 alpha, IL-1 beta, IFN-gamma, and TNF-alpha; in the native livers, mainly of TNF-alpha (with IFN-gamma showing hardly any increase). In general, rejection caused stronger cytokine expression in the grafts than in the native livers. Mild rejection correlated well with strong intragraft expression of IL-6, TNF-alpha, and TNF-beta (early rejection markers); severe rejection with IL-1 alpha, IL-1 beta, IFN-gamma, and TNF-alpha (late rejection markers).In addition to cell augmentation per se, the type of cell augmentation also had an impact on cytokine expression in both grafts and native livers. Cell-augmented (versus tacrolimus-treated) rats showed hardly any differences in intragraft cytokine expression, but the expression of almost all cytokines was significantly stronger in the native livers. With immunosuppression, bone marrow infusion increased intragraft cytokine expression of IL-1 alpha, IL-1 beta, IFN-gamma, and TNF alpha, as well as liver cytokine expression of IL-1 beta, compared to blood transfusion. This finding reflected the more advanced rejection stages in the bone marrow infused group; different types of donor-specific cell augmentation had similar effects on liver cytokine expression. In the absence of myoablative therapy, chimerism levels were low, in both cell-augmented and non-cell-augmented groups. CONCLUSIONS: Rejection and donor-specific cell augmentation independently causes differences in intragraft versus native liver cytokine expression after intestinal transplants. Portal donor-specific blood transfusion, as compared with donor-specific bone marrow infusion, lowered the incidence of rejection and diminished intragraft cytokine up-regulation.     

Effects of dietary intake, appetite, and eating habits on dialysis and non-dialysis treatment days in hemodialysis patients: cross-sectional results from the HEMO study.

OBJECTIVE: To evaluate differences between dietary energy intake (DEI), dietary protein intake (DPI), appetite, dietary patterns, and eating habits during dialysis treatment days (DD) and non-dialysis treatment days (NDD) in 1,901 adults receiving maintenance hemodialysis who were enrolled in the baseline phase of the National Institutes of Health-sponsored Hemodialysis (HEMO) study. DESIGN: A cross-sectional analysis of participants at baseline (before randomization). SETTING: Fifteen clinical centers across the United States. MEASUREMENTS: DEI, DPI, and self-reported assessment of appetite, dietary patterns, and eating habits. RESULTS: For the entire study cohort, total mean (+/- SD) DEI (1,566 +/- 636 kcal/day) and weight-adjusted DEI (23.2 +/- 9.5 kcal/kg/day) were significantly higher (P <.0001) on NDD than on DD (1,488 +/- 620 kcal/day and 22.2 +/- 9.6 kcal/kg/day), respectively. Similarly, DPI was significantly higher (P <.0001) on NDD (65.0 +/- 29.0 g/day and 0.96 +/- 0.43 g/kg/day) than on DD (60.2 +/- 26.5 g/day and 0.90 +/- 0.41 g/kg/day). On DD and NDD, the mean weight-adjusted DEI for the entire cohort was less than the HEMO study standard of care (SOC) of > or =28 kcal/kg/day, whereas on NDD, several subgroups reported dietary protein intakes that were closer to the study's SOC. These included men, patients under 50 years of age, nonblack participants, those without diabetes, those with a normal or mild Index of Co-Existing Disease score, and those on dialysis for more than 5 years. Protein and energy intakes declined with worsening self-reported appetites in both DD and NDD after adjusting for other subgroup effects. CONCLUSION: Dietary energy and protein intakes of HEMO study participants were lower on DD than on NDD, and also lower than the SOC on both days, particularly with regard to energy intake. People receiving maintenance hemodialysis should be counseled to consume adequate amounts of energy and protein daily, especially on DD. Practitioners should monitor closely those patients who report poor appetite and should intervene appropriately.     

Patient and injury characteristics, mortality risk, and length of stay related to child abuse by burning: evidence from a national sample of 15,802 pediatric admissions

OBJECTIVE: To report demographic and injury characteristics of children admitted to burn centers with injuries from suspected child abuse and to assess mortality risk and length of stay compared with patients whose injuries were labeled accidental. SUMMARY BACKGROUND DATA: Little is known about the association between burn injuries from suspected child abuse, mortality, and length of hospitalization. METHODS: Records from 15,802 pediatric admissions (909 with suspected abuse) to 70 burn centers from the American Burn Association National Burn Repository were reviewed. Multivariable logistic regression and Cox regression models were used to assess the relationship between suspected abuse with mortality and length of intensive care and total hospital stays after controlling for age, sex, race, burn etiology (flame vs. scald or contact), % total body surface area burned, and inhalation injury. RESULTS: Children with injuries from abuse were younger (2.4 years vs. 3.9 years, P < 0.001), had larger total body surface area burned (13.0% vs. 9.7%, P < 0.001) and were more likely to incur a scald injury (78.0% vs. 59.2%, P < 0.001). After adjusting for covariates, children with suspected abuse-related injuries were at greater risk of mortality (odds ratio = 4.67, CI = 2.60-8.39, P < 0.001) and required longer intensive care (hazard ratio for discharge [HR] = 0.93, CI = 0.87-1.00, P = 0.044) and total hospital stays (HR = 0.60, CI = 0.56-0.64, P < 0.001). CONCLUSIONS: Compared with children with accidental burn injuries who had similar demographic and injury characteristics, children admitted to burn centers with suspected abuse were at greater risk of mortality and required longer intensive care and total hospital stays.