Mitochondrial complex I defect resulting from exercise-induced lower limb ischemia in patients with peripheral arterial disease.

This study aims to compare the structural and mitochondrial alterations between muscle segments affected by exercise-induced ischemia and segments of the same muscle without ischemia, in the same subject. In a prospective analysis, 34 patients presenting either peripheral arterial disease or chronic coronary syndrome without any evidence of peripheral arterial disease were eligible for inclusion based on findings indicating a need for either a femoro-popliteal bypass or a saphenous harvesting for coronary bypass. Before surgery, we assessed the level of exercise-induced ischemia in proximal and distal sections of the thigh by the measurement of transcutaneous oxygen pressure during an exercise treadmill test. Distal and proximal biopsies of the sartorius muscle were procured during vascular surgical procedures to assess mitochondrial function and morphometric parameters of the sartorius myofibers. Comparisons were made between the distal and proximal biopsies, with respect to these parameters. Thirteen of the study patients that initially presented with peripheral arterial disease had evidence of an isolated distal thigh exercise-induced ischemia, associated with a 35% decrease in the mitochondrial complex I enzymatic activity in the distal muscle biopsy. This defect was also associated with a decreased expression of the manganese superoxide dismutase enzyme and with alterations of the shapes of the myofibers. No functional or structural alterations were observed in the patients with coronary syndrome. We validated a specific model ischemia in peripheral arterial disease characterized by muscular alterations. This "Distal-Proximal-Sartorius Model" would be promising to explore the physiopathological consequences specific to chronic ischemia. NEW & NOTEWORTHY We compared proximal versus distal biopsies of the sartorius muscle in patients with superficial femoral artery stenosis or occlusion and proof of, distal only, regional blood flow impairment with exercise oximetry. We identified a decrease in the mitochondrial complex I enzymatic activity and antioxidant system impairment at the distal level only. We validate a model to explore the physiopathological consequences of chronic muscle ischemia.

[Hypertension during Takayasu's disease: An Algerian single center experience of 279 patients]. / L'hypertension artérielle au cours de la maladie de Takayasu : à propos d'une série monocentrique de 279 patients.

INTRODUCTION: Takayasu arteritis (TA) is an uncommon large vessel arteritis. Lesions produced by the inflammatory process can be stenotic, occlusive, or aneurysmal. Vascular changes lead to the main complications, including hypertension, most often due to renal artery stenosis or, more rarely, stenosis of the suprarenal aorta. AIM OF STUDY: Our study will assess the prevalence of hypertension during TA and describe its clinical profile. MATERIAL AND METHODS: Among 279 patients with TA resulting from single center study over a period of 35 years, we collected 128 hypertensive patients. All have benefited from a vascular exploration. Renal angiography was performed in 85 patients. The classification of Lupi Herrera allowed us to distribute our patients according to the topography of their lesions. Patients are classified according to the degree of severity of their hypertension. Results are statistically analyzed with SPSS 10.0 database. RESULTS: The prevalence of hypertension is 45.8%, mainly affecting young women (87%). It is indicative of arteritis in 24.7%. Its diagnosis is difficult and delayed when arterial stenosis exist: inter-arm blood pressure difference (53.8%), inverse coarctation (30.4%) or unmeasurable blood pressure at the 4 limbs (6.8%). In 54% of cases, hypertension was due to a renal artery stenosis. The presence of arterial hypertension was associated to a poor prognosis: it was severe in 54% of patients and was linked to 70% of deaths observed. CONCLUSION: Arterial hypertension is common during TA. It remains a factor of bad prognosis specially when renovascular hypertension is present.

Hypogammaglobulinemia and risk of severe infection in kidney transplant recipients.

BACKGROUND: Recent data have outlined a link between hypogammaglobulinemia (HGG) and infection risk and suggested that HGG correction may decrease post-transplant infections. METHODS: We analyzed the risk factors of HGG and the relationship between HGG and the risk of severe infection in a cohort of 318 kidney transplant recipients (KTR) who were transplanted between 2003 and 2013. Immunoglobulin (Ig) concentration was measured prospectively at day 15 (D15), month 6 (M6), month 12 (M12), and month 24 (M24) post transplant. RESULTS: The prevalence of IgG HGG was 56% and 36.8% at D15 and M6, respectively. Age was the sole identified risk factors for D15 IgG HGG (odds ratio [OR] 1.02, P = 0.019). Risk factors for M6 IgG HGG were the presence of D15 IgG HGG (OR 6.41, P < 0.001) and treatment of acute rejection (OR 2.63, P = 0.014). Most infections occurred between D15 and M6 post transplant. Only age (hazard ratio 1.03, P < 0.001) was identified as a risk factor of infection between D15 and M6 post transplant. Survival free of infection (overall infections and bacterial or viral infections) did not differ significantly between patients with or without D15 IgG HGG. Only septicemia occurring between M6 and M12 post transplant was more frequently observed in patients with HGG. The low prevalence of severe HGG (<400 mg/dL) did not allow conclusions on the infectious risk associated with this patient subgroup. CONCLUSIONS: This study does not support the existence of a strong link between post-transplant HGG and the risk of severe infections in KTR. Correction of HGG to minimize the risk of severe infections in KTR is thus questionable and needs to be reevaluated in prospective studies.

Financial impact of allogeneic hematopoietic cell transplantation on patients and families over 2 years: results from a multicenter pilot study.

Hematopoietic cell transplantation (HCT) is a procedure that can significantly influence the socioeconomic wellbeing of patients, caregivers and their families. Among 30 allogeneic HCT recipients and their caregivers enrolled on a pilot study evaluating the feasibility of studying financial impact of HCT, 16 agreed to participate in the long-term phase, completed a baseline questionnaire and received phone interviews at 6, 12, 18 and 24 months post HCT. Analyses showed that by 2 years post HCT, 54% of patients who previously contributed to household earnings had not returned to work and 80% of patients/caregivers reported transplant as having moderate to great impact on household income. However, patients' levels of confidence in their abilities to meet household financial obligations increased from baseline to 2 years. A relatively large proportion of patients reported inability to pay for medical care through this time period. Case studies demonstrated that patients' individual perceptions of the financial impact of HCT varies considerably, regardless of actual income. We demonstrate the feasibility of conducting a study to evaluate the financial impact of allogeneic HCT through 2 years post transplantation. Some patients/caregivers continue to experience a significant long-term financial burden after this procedure. Our study lays the foundation for a larger evaluation of patient/caregiver financial burden associated with HCT.

[Clinical impact of the intravesical prostatic protrusion: a review by the LUTS committee of the French Urological Association]. / Impact en pratique clinique de l'indice de protrusion prostatique intravésicale: une revue de la littérature du CTMH de l'AFU.

INTRODUCTION: Intravesical prostatic protrusion (IPP) is a protrusion of the lateral and/or median prostatic lobes into the bladder lumen. IPP can be estimated by suprapubic ultrasound. METHODS: A literature search was conducted in Pubmed/MEDLINE database using the following keywords: intravesical prostatic protrusion; benign prostatic enlargement; treatment outcome; ultrasonography. RESULTS: There are 3 grades of IPP: grade 1, 2 and 3 respectively if IPP ≤ 5mm, if 5-10mm, and if >10mm. IPP was a better prognosis factor than PSA and prostate volume for bladder outlet obstruction (BOO) with a sensibility of 80% and a sensitivity of 68% for grade 3. The progression risk of BOO increased with IPP (grade 1: OR=5.1 [95%CI: 1.6-16.2] and grade ≥ 2 OR=10.4 [95%CI: 3.3-33.4]). IPP was a predictive marker of failure of trial off catheter in patients with acute urinary retention with a 6 folds higher risk for grades ≥ 2. IPP was a prognosis factor for tamsulosine efficacy: 78% of patients with grade ≤ 2 had an improvement >35% of the IPSS-score versus 58% for grade >3 (P<0.01). Patients with grade >3 and a PV< 40cc had a poorer response to tamsulosine. After TURP, IPSS was more improved for grade ≥ 1 with an OR=3.43 (95%CI: 1.03-11.44, P=0.045). CONCLUSION: IPP can be a useful marker for the management of LUTS/BPH.

Pilot study of patient and caregiver out-of-pocket costs of allogeneic hematopoietic cell transplantation.

Patient/caregiver out-of pocket costs associated with hematopoietic cell transplantation (HCT) are not well known. We conducted a pilot study to evaluate patient/caregiver out-of-pocket costs in the first 3 months after allogeneic HCT. Thirty patients were enrolled at three sites. Before HCT, participants completed a baseline survey regarding household income and insurance coverage. Subsequently, they maintained a paper-based diary to track daily out-of-pocket expenses for the first 3 months after HCT. Telephone interviews were conducted to follow-up on the missing/incomplete diaries and on study completion. Twenty-five patients/caregivers completed the baseline survey. Among these, the median pre-tax household income was $66 500 (range, $30-$375 000) and 48% had to temporarily relocate close to the transplant center. Insurance coverage was managed care plan (56%), Medicaid (20%), Medicare (17%) and other (8%). Twenty-two patients/caregivers completed 4 diaries; the median out-of-pocket expenses were $2440 (range, $199-$13 769). Patients/caregivers who required temporary lodging had higher out-of-pocket expenses compared with those who did not (median, $5247 vs $716). Patients/caregivers can incur substantial out-of-pocket costs over the first 3 months, especially if they need to temporarily relocate close to the transplant center. Our study lays the foundation for future research on the early and long-term financial impact of allogeneic HCT on patients/caregivers.

Discrete Element Method studies of the collision of one rapid sphere on 2D and 3D packings.

We performed numerical simulations of one-bead collision on the surface of a static granular medium. The simulations have been done for two- and three-dimensional packings of beads. The effect of the incident bead velocity, the shot angle, the mechanical parameters and the packing structure are analyzed for ordered and disordered 2D packings and only disordered 3D packings. The 2D results are in good agreement with experimental available data. The 3D simulations give good preliminaries results about the shock-wave propagation through the stacking and provides new insights in the ejection process ("Splash function").

Friction and rotation modes in a packing of cylinders under shear stress.

We study the influence of collective processes such as rotations on the effective friction of sheared granular media made of two-dimensional array of cylinders. An original experimental device allows us to measure simultaneously grain rotations and the global friction force between the packing and the basal plane. It is shown that the correlation between these two quantities can be analyzed at two different time scales: 1. Averaging over the duration of a whole experiment, the mean sliding behavior of the first row on the base of the packing describes satisfactorily the global friction force. 2. At short-time, description of this correlation requires the knowledge of the propagation of rotation perpendicularly to the shear direction.

Collective response of an array of rotating particles to fluctuating confining forces

We study the influence of fluctuations of confining forces on the rotation patterns in a dense array of cylinders. Our theoretical studies are motivated by new results from detailed time-resolved experimental measurements. In order to calculate the system's evolution in time at each moment, a molecular-dynamics code adapted to the system is developed. The numerical procedure is tested by a comparison with rigorous predictions derived analytically. The chain's reaction on oscillating confining forces is analyzed numerically for different typical cases. Our theoretical results reproduce the striking features of the experimental data. A quantitative analysis of the experimental data is performed by a computation of their power spectrum and of spatial and temporal correlation functions. From our comparison of the theoretical and experimental results we conclude that the experimental rotation patterns result of random superpositions of different steady-state patterns ("collective random walk").