Bovine pericardial patch: A good alternative in femoral angioplasty

OBJECTIVE

Bovine pericardial patch (BPP) is currently used in femoral angioplasty as an alternative for autologous vein patch (AVP), but studies comparing the results of the two methods are scarce. In this retrospective study, we aimed to discover the differences between BPP and AVP closure in long-term durability.

METHODS

This study consisted of all femoral endarterectomies with BPP closure performed in Helsinki University Hospital from January 1, 2014, to December 31, 2017. For comparison, the same number of consecutive patients who underwent femoral endarterectomy with AVP closure from January 1, 2014, to October 16, 2016, were reviewed. Follow-up ended December 31, 2020. The mean follow-up was 19 months (range, 0-74 months) in the BPP group and 22 months (range, 0-79 months) in the AVP group. The primary endpoint was primary patency. Secondary endpoints were restenosis at patch site detected by imaging or perioperatively, patch rupture, and deep surgical wound infection. Propensity score analysis was performed for adjustment of differences between the AVP and BPP groups.

RESULTS

Overall primary patency was superior in the AVP group compared with the BPP group: at 1 year, 96.5% vs 85.0% and at 5 years, 83.0% vs 72.3% (P = .04). In propensity score-matched pairs (n = 92), no difference was found between the groups in primary patency: 95.7% and 95.7% at 1 year and 92.5% and 78.6% at 5 years (P = .861) or in freedom from restenosis: 100% and 100% at 1 year and 89.1% and 84.0% at 5 years (P = .057). Deep wound infections occurred slightly more often after BPP closure (8%) than after AVP closure (4%), but the difference was not statistically significant (P = .144). There were no patch ruptures in the BPP group, but in the AVP group, there were five ruptures (3.5%) (P = .024).

CONCLUSIONS

BPP is compatible to AVP in femoral endarterectomy in patency and can be regarded as the safer choice considering the risk of patch rupture.

Impact of the COVID-19 pandemic on the management of gallstone surgery: A Swedish population-based study

Background:

The SARS-CoV-2 pandemic has had a significant impact on healthcare delivery. As resources are reallocated, surgery for benign conditions such as gallstone disease is often given low priority. We do not know how this has affected the risk of patients with uncomplicated gallstone disease to develop acute cholecystitis, biliary pancreatitis, or obstructive jaundice.

Methods:

The study was based on the population-based Swedish Register of Gallstone Surgery and Endoscopic Retrograde Cholangiopancreatography. The period prior to the first cases of COVID-19 in Sweden, that is, April 2015–March 2020, was compared to the period April 2020–March 2021 during the pandemic. Stratification was made for factors potentially related to priority decisions.

Results:

Altogether, 78,211 procedures were performed during the period of the study. The ratio of procedures performed during April 2020–March 2021 in the previous 5 years was 0.960 ( p = 0.113). The ratio of procedures on patients aged <65 years was 0.945 ( p = 0.008), on patients aged 65–80 years was 0.964 ( p = 0.423), on patients aged >80 years was 1.336 ( p = 0.025), on men was 1.001 ( p = 0.841), on women was 0.934 ( p = 0.006), on procedures completed laparoscopically was 0.964 ( p = 0.190), on procedures completed with open approach was 0.659 ( p = 0.044), on acute procedures was 1.218 ( p = 0.016), on planned procedures was 0.791 ( p < 0.001), on procedures performed for biliary colic was 0.808 ( p < 0.001), on procedures performed for acute cholecystitis was 1.274 ( p = 0.012), for biliary pancreatitis was 1.192 ( p = 0.037), and for obstructive jaundice was 1.366 ( p = 0.008).

Conclusions:

The COVID-19 has had a great impact on how gallstone surgery has been organized over the last 2 years. The decreased number of planned procedures probably reflects the reallocation of resources during the pandemic. However, whether the increasing number of acute procedures is the result of postponed planned surgery or a continuation of a long-term trend toward more acute surgery remains unanswered. Further studies are needed to assess and evaluate how this has affected public health and health economics.

Procurement and Evaluation of Hepatocytes for Transplantation From Neonatal Donors After Circulatory Death

Hepatocyte transplantation is a promising treatment for liver failure and inborn metabolic liver diseases, but progress has been hampered by a scarcity of available organs. Here, hepatocytes isolated from livers procured for a neonatal hepatocyte donation program within a research setting were assessed for metabolic function and suitability for transplantation. Organ donation was considered for infants who died in neonatal intensive care in the Stockholm region during 2015–2021. Inclusion was assessed when a decision to discontinue life-sustaining treatment had been made and hepatectomy performed after declaration of death. Hepatocyte isolation was performed by three-step collagenase perfusion. Hepatocyte viability, yield, and function were assessed using fresh and cryopreserved cells. Engraftment and maturation of cryopreserved neonatal hepatocytes were assessed by transplantation into an immunodeficient mouse model and analysis of the gene expression of phase I, phase II, and liver-specific enzymes and proteins. Twelve livers were procured. Median warm ischemia time (WIT) was 190 [interquartile range (IQR): 80–210] minutes. Median viability was 86% (IQR: 71%–91%). Median yield was 6.9 (IQR: 3.4–12.8) x10⁶ viable hepatocytes/g. Transplantation into immunodeficient mice resulted in good engraftment and maturation of hepatocyte-specific proteins and enzymes. A neonatal organ donation program including preterm born infants was found to be feasible. Hepatocytes isolated from neonatal donors had good viability, function, and engraftment despite prolonged WIT. Therefore, neonatal livers should be considered as a donor source for clinical hepatocyte transplantation, even in cases with extended WIT.

Optimizing gamma-ray spectrometers for UAV-borne surveys with geophysical applications

Heavy duty unmanned aerial vehicles (UAVs) have made it possible to fly with large gamma-ray spectrometers that weigh several kilograms. Moreover, they can be purchased at an affordable price. These large UAV-borne gamma-ray detection systems are used to map the naturally occurring radionuclides ⁴⁰K, ²³⁸U, ²³²Th. Such platforms have the advantage that they can be deployed over terrain that is difficult to access, while still maintaining a high spatial resolution. In contrast to UAV-borne radioactive pollution studies, the naturally occurring radionuclides have a much lower activity and therefore require longer integration time, slower flying speed or a larger detector, in order to effectively determine the spatial radionuclide distribution. Therefore, the question arises: what is the minimum practical detector size required to successfully map ⁴⁰K, ²³⁸U and ²³²Th concentrations from UAV platforms. In this study an agricultural field has been mapped with three different scintillator-based gamma-ray spectrometers: a 2000 ml, 1000 ml, and 350 ml detector. They were mounted together on the same UAV. At a flying height of 20 m and a speed of 5.6 m s^-1 the field was mapped. The various aerial measurements were compared to each other and to the ground-based measurements. The field had a low spatial variation in the ⁴⁰K concentration (relative standard deviation (RSD) = 9%) and a larger variation for ²³⁸U and ²³²Th concentrations (RSD = 24% and 31% respectively). Radionuclide concentrations have been extracted from the survey data by Full Spectrum Analysis (FSA). Uncertainties and variances of the radionuclides have been determined by using two methods. Firstly, they are calculated directly from the FSA output and secondly they are extracted from a variogram. The latter incorporates spatial variation and was shown to provide a lower uncertainty. When using small detectors, the former approach could lead to the conclusion that the uncertainty is larger than the variance, while the variogram approach does capture the spatial variation. All three detectors were able to characterize the spatial distribution of the ²³²Th concentration. It is shown that the ²³²Th concentration is a good predictor of the sand and clay fraction of the topsoil in the field. By comparing the UAV-borne measurements to the ground-based measurements it is found that UAV-borne measurements at 20 m height are less sensitive to extreme values than ground-based measurements and they have the tendency to shift to the mean concentration of the area. The results of this study can be used to optimize the detector volume, survey height, and survey speed to maintain an acceptable accuracy for gamma-ray studies with small UAV-borne detectors.

Footprint and height corrections for UAV-borne gamma-ray spectrometry studies

Advancements in the development of gamma-ray spectrometers (GRS) have led to small and lightweight spectrometers that can be used under unmanned aerial vehicles (UAVs). Airborne GRS measurements are used to determine radionuclide concentrations in the ground, among which the natural occurring radionuclides ⁴⁰K, ²³⁸U, and ²³²Th. For successful applications of these GRS sensors, it is important that absolute values of concentrations can be measured. To extract these absolute radionuclide concentrations, airborne gamma-ray data has to be corrected for measurement height. However, the current analysis models are only valid for the height range of 50-250 m. The purpose of this study is to develop a procedure that correctly predicts the true radionuclide concentration in the ground when measuring in the UAV operating range of 0-40 m. An analytical model is developed to predict the radiation footprint as a function of height. This model is used as a tool to properly determine a source-detector geometry to be used in Monte-Carlo simulations of detector response at various elevations between 0 and 40 m. The analytical model predicts that the smallest achievable footprint at 10 m height lies between 22 and 91 m and between 40 and 140 m at 20 m height. By using Monte-Carlo simulations it is shown that the analytical model correctly predicts the reduction in full energy peak gamma-rays, but does not predict the Compton continuum of a spectrum as a function of height. Therefore, Monte-Carlo simulations should be used to predict the shape and intensity of gamma-ray spectra as a function of height. A finite set of Monte-Carlo simulations at intervals of 5 m were used for the analysis of GRS measurements at heights up to 35 m. The resulting radionuclide concentrations at every height agree with the radionuclide concentration measured on the ground.

Outcome after Hybrid Outflow Interventions for Chronic Limb-threatening Ischemia

BACKGROUND AND AIMS

Because chronic limb-threatening ischemia (CLTI) is often associated with multilevel arterial disease, it usually requires revascularization at different sites of the limb vasculature. We aim to assess the outcome of the hybrid interventions including open surgical revascularization together with outflow segment percutaneous transluminal angioplasty (PTA) in patients with chronic limb-threatening ischemia.

MATERIAL AND METHODS

This study included all hybrid outflow-PTA interventions (n = 80) on patients suffering from CLTI performed in Helsinki University Hospital between 2003 and 2015. Follow-up ended on 31 December 2019. Patient data were prospectively collected into our vascular registry and scrutinized retrospectively. Thirty-one patients (39%) suffered from rest pain (Rutherford category IV) and 49 patients (61%) had ischemic ulcers (Rutherford category V-VI). The most common open surgical procedure was femoral endarterectomy (n = 63, 79%) and the most common endovascular procedure was superficial femoral artery percutaneous transluminal angioplasty (n = 65, 81%). Mean follow-up time was 56 months (range: 4 days-183 months).

RESULTS

Limb salvage was at 30 days-92%, at 1 year-91%, and at 5 and 10 years-86%. Survival and amputation-free survival were at 30 days-93% and 86%, at 1 year-80% and 76%, at 5 years-51% and 48%, and at 10 years-21% and 21%. Wound healing at 3, 6, and 12 months was 48%, 71%, and 87%. Freedom from target lesion revascularization was at 30 days-97%, at 1 year-88%, at 5 years-72%, and at 10 years-66%.

CONCLUSION

Hybrid outflow revascularization is an important tool in the vascular surgeon's armamentarium for treatment of patients with multilevel arterial disease causing chronic limb-threatening ischemia.

Herd and environmental determinants of reproductive performance in Swedish dairy herds, 2001-2009

This was a retrospective cohort study of Swedish dairy herds. Summary measures of production and reproductive performance, details of soil, moss mineral concentrations, and temperature and rainfall measurements at each herd location were available for the period September 2001 to August 2009. A Bayesian mixed-effects regression model including spatial and non-spatial heterogeneity terms was developed to quantify associations between hypothesised explanatory variables and mean herd breeding interval, defined as the difference between mean calving to last service interval and mean calving to first service interval for each fiscal year. Mean herd breeding intervals were shorter in herds with greater than 80% Swedish Red Cattle, herds with lower mean age at first calving, herds comprised of older cows and in larger herds. None of the soil composition or moss mineral concentration estimates were associated with mean herd breeding interval and the effect of temperature and rainfall on mean herd breeding interval was small. We conclude that environmental conditions (soil composition, moss mineral concentrations, environmental temperature and rainfall) had relatively minor effects on dairy herd reproductive performance in Sweden between 2001 and 2009.

Risk assessment of high concentrations of molybdenum in forage

Molybdenum is toxic to ruminants when present in high levels in forage, causing physiological copper deficiency. A critical level for ruminants is 3-10 mg Mo kg^-1 dry matter. The average Mo level varies considerably between different arable soils, depending mainly on soil parent material. This study investigated the possibility of using various existing sources of geospatial information (geophysical, biogeochemical and soil chemical) to develop a geography-based risk assessment system. Forage samples (n = 173) were collected in 2006-2007. Three types of national geoscientific datasets were tested: (1) SEPA topsoil, comprising data from arable land within the Swedish environmental monitoring programme; (2) SGU biogeochemical, containing data from aquatic plant root material collected in small streams; and (3) SGU geophysical, consisting of data from airborne gamma-ray scanning. The digital postcode area map was used for geocoding, with Mo concentrations in forage assigned to arable parts of the corresponding postcode area. By combining this with the three national geoscientific databases, it was possible to construct a risk map using fuzzy classification depicting High-risk, Intermediate-risk, Low-risk and Very-low-risk areas. The map was validated using 42 randomly selected samples. All samples but one with Mo > 3 mg kg^-1 were found in postcode areas designated High risk. Thus, the risk map developed seems to be useful as a decision support system on where standard forage analyses need to be supplemented with Mo analyses.

In vivo imaging of Lyme arthritis in mice by [18F]fluorodeoxyglucose positron emission tomography/computed tomography

OBJECTIVE

Lyme borreliosis (LB) is a tick-borne infectious disease caused by Borrelia burgdorferi spirochaetes, which are able to disseminate from the tick-bite site to distant organs. Mouse models are widely used to study LB and especially Lyme arthritis (LA), but only a few whole-animal in vivo imaging studies on the pathogenesis of B. burgdorferi infection in mice have been published so far. The existing imaging techniques have their drawbacks and, therefore, novel tools to complement the array of available LB imaging methodologies are needed.

METHOD

The applicability of positron emission tomography combined with computed tomography (PET/CT) imaging was evaluated as a method to monitor LB and especially LA in the C3H/HeN mouse model infected with wild-type B. burgdorferi N40 bacteria. The imaging results were compared with the traditional LA analysis methods, such as tibiotarsal joint swelling and histopathological assessment of joint inflammation.

RESULTS

PET/CT imaging provided high-resolution images with quantitative information on the spatial and temporal distribution of the [¹⁸F]fluorodeoxyglucose ([¹⁸F]FDG) tracer in B. burgdorferi-infected mice. The [¹⁸F]FDG accumulated in the affected joints and activated lymph nodes of infected mice, while the tracer signal could not be visualized in these organs in uninfected control animals. Importantly, in vivo PET/CT imaging data were in agreement with the histopathological scoring of inflammation of mouse joints.

CONCLUSION

PET/CT imaging with [¹⁸F]FDG is a reliable method to longitudinally monitor the development and progression of B. burgdorferi infection-induced inflammation in vivo in mouse joints.

Multiple sclerosis-associated retrovirus and optic neuritis

One prognostic factor for early multiple sclerosis (MS) patients to develop a definite MS may be the presence of the MS-associated retrovirus (MSRV) in the cerebrospinal fluid (CSF). We designed a specific study on a cohort of optic neuritis (ON) patients to evaluate the MSRV-dependent conversion to MS relative to the prediction conferred by magnetic resonance imaging (MRI) and CSF abnormalities. At follow-up, 33.3% MSRV+ and 0% MSRV− ON patients developed MS ( P=0.03). The prediction value is lower than that given by CSF and MRI abnormalities (42.3%). This intriguing finding is discussed in the light of the abundant discrepancies observed in the MSRV literature.

Cerebrospinal fluid levels of brain specific proteins in optic neuritis

This study evaluates levels of cerebrospinal fluid (C SF) brain-specific proteins (BSP) in subjects with optic neuritis (O N) who are at high risk of progression to multiple sclerosis (MS). Forty-one subjects had acute O N and 17 subjects with other neurological diseases (OND) served as controls. Twenty-o ne subjects with O N had white matter lesions on magnetic resonance imaging (MRI) and intrathecal synthesis of oligoclonal IgG bands (OB) consistent with being at high risk of progression to MS; eight of whom later were diagnosed with clinically definite MS (C DMS). Levels of S100B, ferritin and two neurofilament heavy chain phosphoforms (NfHSMI34 and NfHSMI35) were analysed using ELISA technique. A putative index of ‘axonal health’ was expressed as a ratio of NfHSMI34 to NfHSMI35. NfHSMI34 and the NfHSMI34:SMI35 were significantly elevated in subjects with O N compared to controls. No significant differences in levels of C SF BSP were seen between O N subjects with C DMS plus those at high risk of progression to MS and O N subjects with normal MRI and negative C SF analysis. In conclusion, there is evidence of axonal damage in subjects who present with O N, which is independent of the diagnosis of C DMS.

Cdc20 and securin overexpression predict short-term breast cancer survival

BACKGROUND

Cdc20 is an essential component of cell division and responsible for anaphase initiation regulated by securin degradation. Cdc20 function is strongly regulated by the spindle assembly checkpoint to ensure the timely separation of sister chromatids and integrity of the genome. We present the first results on Cdc20 in a large clinical breast cancer material.

METHODS

The study was based on 445 breast cancer patients with up to 20 years of follow-up (mean 10.0 years). DNA content was determined by image cytometry on cell imprints, and Cdc20 and securin immunohistochemistry on tissue microarrays of breast cancer tissue.

RESULTS

In our results, high Cdc20 and securin expression was associated with aneuploid DNA content. In prognostic analyses, high Cdc20 immunoexpression alone and in combination with high securin immunoexpression indicated aggressive course of disease and up to 6.8-fold (P<0.001) risk of breast cancer death. Particularly, high Cdc20 and securin immunoexpression identified a patient subgroup with extremely short, on average 2.4 years, breast cancer survival and triple-negative breast cancer (TNBC) subtype.

CONCLUSIONS

We report for the first time the association of high Cdc20 and securin immunoexpression with extremely poor outcome of breast cancer patients. Our experience indicates that Cdc20 and securin are promising candidates for clinical applications in breast cancer prognostication, especially in the challenging prognostic decisions of TNBC.

Casein hydrolysate diet controls intestinal T cell activation, free radical production and microbial colonisation in NOD mice

AIMS/HYPOTHESIS

Dietary and microbial factors and the gut immune system are important in autoimmune diabetes. We evaluated inflammatory activity in the whole gut in prediabetic NOD mice using ex vivo imaging of reactive oxygen and nitrogen species (RONS), and correlated this with the above-mentioned factors.

METHODS

NOD mice were fed a normal diet or an anti-diabetogenic casein hydrolysate (CH) diet. RONS activity was detected by chemiluminescence imaging of the whole gut. Proinflammatory and T cell cytokines were studied in the gut and islets, and dietary effects on gut microbiota and short-chain fatty acids were determined.

RESULTS

Prediabetic NOD mice displayed high RONS activity in the epithelial cells of the distal small intestine, in conjunction with a proinflammatory cytokine profile. RONS production was effectively reduced by the CH diet, which also controlled (1) the expression of proinflammatory cytokines and colonisation-dependent RegIIIγ (also known as Reg3g) in ileum; (2) intestinal T cell activation; and (3) islet cytokines. The CH diet diminished microbial colonisation, increased the Bacteroidetes:Firmicutes ratio, and reduced lactic acid and butyric acid production in the gut.

CONCLUSIONS/INTERPRETATION

Epithelial RONS production and proinflammatory T cell activation appears in the ileum of NOD mice after weaning to normal laboratory chow, but not after weaning to an anti-diabetogenic CH diet. Our data suggest a link between dietary factors, microbial colonisation and mucosal immune activation in NOD mice.

The quality of the outdoor environment influences childrens health -- a cross-sectional study of preschools

AIM

To test how the quality of the outdoor environment of child day care centres (DCCs) influences children's health.

METHODS

The environment was assessed using the Outdoor Play Environmental Categories (OPEC) tool, time spent outdoors and physical activity as measured by pedometer. 172/253 (68%) of children aged 3.0-5.9 from nine DCCs participated in Southern Sweden. Health data collected were body mass index, waist circumference, saliva cortisol, length of night sleep during study, and symptoms and well-being which were scored (1-week diary - 121 parent responders). Also, parent-rated well-being and health of their child were scored (questionnaire, 132 parent responders). MANOVA, ANOVA and principal component analyses were performed to identify impacts of the outdoor environment on health.

RESULTS

High-quality outdoor environment at DCCs is associated with several health aspects in children such as leaner body, longer night sleep, better well-being and higher mid-morning saliva cortisol levels.

CONCLUSION

The quality of the outdoor environment at DCCs influenced the health and well-being of preschool children and should be given more attention among health care professionals and community planners.

End-stage renal disease and critical limb ischemia: a deadly combination?

OBJECTIVES

This study was planned to evaluate the prognostic impact of end-stage renal disease (ESRD) in patients with critical leg ischemia (CLI) undergoing infrainguinal revascularization.

MATERIALS AND METHODS

1425 patients who underwent infrainguinal revascularization for CLI were the subjects of the present analysis. Ninety-five patients had ESRD (eGFR < 15 ml/min/m²), and of them 66 (70%) underwent percutaneous transluminal angioplasty and 29 (30%) underwent bypass surgery.

RESULTS

ESRD patients had significantly lower overall survival (at 3-year, 27.1% vs. 59.7%, p < 0.0001), leg salvage (at 3-year, 57.7% vs. 83.0%, p < 0.0001), and amputation free survival (at 3-year, 16.2% vs. 52.9%, p < 0.0001) than patients with no or less severe renal failure. The difference in survival was even greater between 86 one-to-one propensity matched pairs (at 3-year, 23.1% vs. 67.3%, p < 0.0001). ESRD was an independent predictor of all-cause mortality (RR 2.46, 95%CI 1.85-3.26). Logistic regression showed that age ≥ 75 years was the only independent predictor of 1-year all-cause mortality (OR 4.92, 95%CI 1.32-18.36). Classification and regression tree analysis showed that age ≥ 75 years and, among younger patients, bypass surgery for leg ulcer and gangrene were associated with significantly higher 1-year mortality

CONCLUSIONS

Lower limb revascularization in patients with CLI and end-stage renal failure is associated with favourable leg salvage. However, these patients have a very poor survival and this may jeopardize any attempt of revascularization. Further studies are needed to identify ESRD patients with acceptable life expectancy and who may benefit from lower limb revascularization.

Angiosome Theory: Fact or Fiction?

The angiosome concept delineates the human body into three-dimensional blocks of tissue fed by specific arterial and venous sources named “angiosomes.” Adjacent angiosomes are connected by a vast compensatory collateral web, or “choke vessels.” This concept may provide new information applicable to improving targeted revascularization of ischemic tissue lesions.

A few dedicated studies available seem to favor this strategy, as encouraging ulcer healing and limb preservation are reported in connection with both bypass and endovascular techniques based on these principles.

The theory on the angiosome model of revascularization (AMV) may help the clinician to better refine vessel selection, vascular access, and specific strategies in the revascularization of critically ischemic legs with tissue lesions. Specific applications of angiosome-guided revascularization were recently suggested for patients with diabetes or renal insufficiency, with ischemic tissue lesions of the lower limb, and extended large- and medium-size collateral network decay. For these cases, the concept may allow deliberate arterial reconstruction following individual wound topographies in specific ischemic areas, although deprived from “rescue-vessel” supply. The AMV theory may contribute to a shift in common reperfusion options.

However, the data available is suggestive and does not provide strong evidence as factors such as case mix and the severity of ischemia are unsatisfactorily controlled.

At present, the evidence is scarce as to the effect of the severity of the arterial disease. In all comparisons, the groups treated are likely to be dissimilar and mismatched. The angiosome concept is postulated to be valid especially in diabetics, whose ischemic lesions tend to heal worse than those of non-diabetics.

The role of chronic kidney disease as a predictor of outcome after revascularisation of the ulcerated diabetic foot

AIMS/HYPOTHESIS

The aim of the study was to stratify the risk of diabetic patients with leg ulcer or gangrene undergoing infrainguinal revascularisation for critical limb ischaemia.

METHODS

The study cohort included 732 revascularisation procedures performed in 597 diabetic patients with ulcer or gangrene. Logistic regression and CART analysis were used for identification of predictors of 1-year outcome.

RESULTS

Logistic regression showed that chronic kidney disease (CKD) class (OR 1.38, 95% CI 1.16, 1.65) was an independent predictor of 1-year leg salvage (area under the receiver operating characteristic [ROC] curve 0.60, 95% CI 0.54, 0.65). The terminal nodes of the CART for 1-year leg salvage were CKD classes 4-5, the level (infrapopliteal vs femoropopliteal revascularisation), type of revascularisation (bypass surgery vs percutaneous transluminal angioplasty) and gangrene (area under the ROC curve 0.62, 95% CI 0.57, 0.68). Logistic regression showed that pulmonary disease (OR 1.76, 95% CI 1.11, 2.78), CKD class (OR 1.43, 95% CI 1.24, 1.65), foot gangrene (OR 1.76, 95% CI 1.21, 2.60) and patient age (OR 1.02, 95% CI 1.01, 1.04) were independent predictors of 1-year amputation-free survival (area under the ROC curve 0.65, 95% CI 0.60, 0.69). The terminal nodes of the CART for 1-year amputation-free survival were CKD classes 3-5, patient's age of ≥ 75 years and foot gangrene (area under the ROC curve 0.64, 95% CI 0.60, 0.68).

CONCLUSIONS/INTERPRETATION

CKD is a formidable risk factor for poor intermediate outcome after infrainguinal revascularisation in diabetic patients with foot ulcer or gangrene. CART analysis indicates that foot gangrene is also a significant risk factor for adverse outcome.

Tertiary patency as a measure of active revascularization policy for leg salvage

BACKGROUND

An active surgical strategy to save lower limbs of patients with critical leg ischemia includes not only infrainguinal bypass surgery but also repeated surgery when needed. A failed infrainguinal bypass often threatens viability of the patient's legs, at which point a redo bypass procedure with a new graft may be the only alternative to major amputation. We assessed tertiary patency, defined as the whole period of time with a patent infrainguinal graft in a leg, to illustrate future potential of limb salvage surgery after a failed bypass.

METHODS

A total of 593 patients with critical leg ischemia and tissue defects (Fontaine IV) who underwent infrainguinal bypass surgery between January 2000 and December 2005 at our institution were included in this retrospective study.

RESULTS

Secondary and tertiary patency rates were 95 ± 1% and 96 ± 3% at 1 month, 75 ± 2% and 82 ± 2% at 1 year, and 61 ± 2% and 70 ± 3% at 5 years, respectively, p = 0.003. Leg salvage rate was 94 ± 1% at 1 month, 83 ± 2% at 1 year, and 78 ± 2% at 5 years. There was no significant difference between leg salvage and tertiary patency rates, p = 0.281.

CONCLUSION

Tertiary patency rate was higher than the secondary patency rate. This result might reflect active limb salvage surgery with satisfactory results. The absence of a gap between tertiary patency and leg salvage rates indicates the importance of a patent infrainguinal bypass graft to save lower limbs of patients with ischemic tissue defects.

Infrainguinal percutaneous transluminal angioplasty or bypass surgery in patients aged 80 years and older with critical leg ischaemia

Background

Infrainguinal revascularization for critical leg ischaemia (CLI) in patients aged 80 years and over is associated with increased operative risk. The aim was to compare the results of percutaneous transluminal angioplasty (PTA) and bypass surgery in these patients.

Methods

Some 584 consecutive patients aged at least 80 years treated with either PTA (277) or bypass surgery (307) for CLI between 2000 and 2007 were included in this study.

Results

After 2 years PTA achieved better results than bypass surgery (leg salvage: 85·4 versus 78·7 per cent, P = 0·039; survival: 57·7 versus 52·3 per cent, P = 0·014; amputation-free survival (AFS): 53·0 versus 44·9 per cent, P = 0·005). Cox regression analysis showed that increased age (relative risk (RR) 1·05, 95 per cent confidence interval 1·02 to 1·08), decreased estimated glomerular filtration rate (RR 0·99, 0·99 to 1·00), diabetes (RR 1·30, 1·04 to 1·62), coronary artery disease (RR 1·36, 1·05 to 1·75) and bypass surgery (RR 1·55, 1·24 to 1·93) were associated with decreased AFS. In 95 propensity score-matched pairs, leg salvage at 2 years (88 versus 75 per cent; P = 0·010) and AFS (53 versus 45 per cent; P = 0·033) were significantly better after PTA. Classification and regression tree analysis suggested that PTA was associated with better 1-year AFS, especially in patients with coronary artery disease (63·8 versus 48·9 per cent; P = 0·008).

Conclusion

When feasible, a strategy of PTA first appears to achieve better results than infrainguinal bypass surgery in patients aged 80 years and older.

High Leg Salvage Rate after Infrainguinal Bypass Surgery for Ischemic Tissue Loss (Fontaine IV) is Compromised by the Short Life Expectancy

Background and Aims:

Most studies analysing the prognosis of infrainguinal bypass surgery (IBS) in patients with critical leg ischemia (CLI) have combined the outcome of patients with rest pain and tissue loss. The aim of the present study was to evaluate amputation-free survival (AFS) after IBS in patients with the most advanced form of peripheral arterial disease, CLI with tissue loss (Fontaine IV), and to analyse the risk factors for an adverse outcome.

Patients and Methods:

636 patients with CLI and tissue loss who underwent unilateral IBS between January 2000 and December 2006 at our institution were included in this retrospective study.

Results:

At one year, the leg salvage, survival and amputation-free survival rates were 83%, 71% and 55%, respectively, and at five years 76%, 38% and 30%, respectively. In univariate analysis, diabetes was associated with decreased AFS. In multivariate analysis, age, coronary artery disease, chronic pulmonary disease, gangrene and renal insufficiency were independent risk factors for decreased AFS.

Conclusion:

Infrainguinal bypass grafting results in a high rate of leg salvage. Amputation-free survival was low during the follow-up due to the high mortality of patients with CLI and tissue loss. Several co-morbidities of the CLI patients were associated with decreased amputation-free survival.

Arm vein conduit vs prosthetic graft in infrainguinal revascularization for critical leg ischemia

BACKGROUND

One-piece great saphenous vein (GSV) is the conduit of choice in infrainguinal revascularizations for critical limb ischemia (CLI). Unfortunately, adequate length of usable GSV is not always available. Despite inferior patency rates compared with GSV, prosthetic and arm vein conduits are generally considered usable. The purpose of this study was to compare the outcome of infrainguinal arm vein and prosthetic bypass.

MATERIAL AND METHODS

We retrospectively reviewed 290 consecutive infrainguinal bypasses for CLI using arm vein conduit (n = 130) or prosthetic graft (n = 160) during January 2000 and December 2006 at our institution. The groups were compared for risk factors, indication for surgery, and runoff score. Survival, leg salvage, and patency rates were calculated with the Kaplan-Meier method.

RESULTS

Median surveillance time was 35 months (range 0-118 months). The age, gender, and usual risk factors were similar in arm vein and prosthetic groups, except cerebrovascular disease that was more common in the prosthetic group (P = .011). Indication for surgery was CLI. In the arm vein group, more than two-thirds (70.2%) of the procedures were for ischemic ulcer or gangrene, whereas in the prosthetic group the main indication was ischemic rest pain (51.3%). When the outcome of femoropopliteal bypasses was analyzed, the difference between groups was not statistically significant. However, in infrapopliteal revascularizations primary patency, assisted primary patency, and secondary patency rates at 3 years were significantly better in the arm vein group: 28.3% (SE +/- 6.3%) vs 9.6% (SE +/- 8.1%) (P = .031), 56.8% (SE +/- 6.6%) vs 10.4% (SE +/- 8.7%) (P = .000), and 57.4% (SE +/- 6.6) vs 11.2% (SE +/- 9.3%) (P = .000), respectively. Leg salvage and survival at 3 years were 75.0% (SE +/- 4.9%) vs 57.1% (SE +/- 8.8%) (P = .005) and 58.8% (SE +/- 5.1%) vs 39.5% (SE +/- 7.7%) (P = .007), respectively.

CONCLUSION

Arm vein conduits, even when spliced, are superior to prosthetic grafts in terms of midterm assisted primary patency, secondary patency, and leg salvage in infrapopliteal bypasses for CLI.

Gender equality in the work of local research ethics committees in Europe: a study of practice in five countries

BACKGROUND

Funding organisations and research ethics committees (RECs) should play a part in strengthening attention to gender equality in clinical research. In the research policy of European Union (EU), funding measures have been taken to realise this, but such measures are lacking in the EU policy regarding RECs.

OBJECTIVE

To explore how RECs in Austria, Germany, Ireland, The Netherlands and Sweden deal with gender equality issues by asking two questions: (1) Do existing procedures promote representation of women and gender expertise in the committee? (2) How are sex and gender issues dealt with in protocol evaluation?

METHODS

Two RECs were selected from each country. Data were obtained through interviews with key informants and content analysis of relevant documents (regulations, guidelines and review tools in use in 2003).

RESULTS

All countries have rules (mostly informal) to ensure the presence of women on RECs; gender expertise is not required. Drug study protocols are carefully evaluated, sometimes on a formal basis, as regards the inclusion of women of childbearing age. The reason for excluding either one of the sexes or including specific groups of women or making a gender-specific risk-benefit analysis are investigated by some RECs. Such measures are, however, neither defined in the regulations nor integrated in review tools.

CONCLUSIONS

The RECs investigated in five European member states are found to pay limited attention to gender equality in their working methods and, in particular in protocol evaluation. Policy and regulations of EU are needed to strengthen attention to gender equality in the work of RECs.

Peroxisome proliferator activated receptor gamma activity is low in mature primary human visceral adipocytes

AIMS/HYPOTHESIS

The amount of visceral fat mass strongly relates to insulin resistance in humans. The transcription factor peroxisome proliferator activated receptor gamma (PPARG) is abundant in adipocytes and regulates genes of importance for insulin sensitivity. Our objective was to study PPARG activity in human visceral and subcutaneous adipocytes and to compare this with the most common model for human disease, the mouse.

MATERIALS AND METHODS

We transfected primary human adipocytes with a plasmid encoding firefly luciferase controlled by PPARG response element (PPRE) from the acyl-CoA-oxidase gene and measured PPRE activity by emission of light.

RESULTS

We found that PPRE activity was 6.6-fold higher (median) in adipocytes from subcutaneous than from omental fat from the same subjects (n = 23). The activity was also 6.2-fold higher in subcutaneous than in intra-abdominal fat cells when we used a PPARG ligand-binding domain-GAL4 fusion protein as reporter, demonstrating that the difference in PPRE activity was due to different levels of activity of the PPARG receptor in the two fat depots. Stimulation with 5 micromol/l rosiglitazone did not induce a PPRE activity in visceral adipocytes that was as high as basal levels in subcutaneous adipocytes. Interestingly, in mice of two different strains the PPRE activity was similar in visceral and subcutaneous fat cells.

CONCLUSIONS/INTERPRETATION

We found considerably lower PPARG activity in visceral than in subcutaneous primary human adipocytes. Further studies of the molecular mechanisms behind this difference could lead to development of drugs that target the adverse effects of visceral obesity.

Airborne PCB as a contamination risk on freeze-drying of sediment

In a study of polychlorinated biphenyls (PCB) in freeze-dried sediments from Swedish lakes, the samples were found to contain unexpectedly high concentrations of PCBs. In one of the lakes (Björken), e.g. the concentration of PCB-28 was found to be 189 ng/g dw after freeze-drying compared to 7 ng/g dw after air-drying of the sediment and therefore our hypothesis was that the contamination had occurred during the freeze-drying procedure. Hence, a dry reference sediment (RS) was used in order to identify potential sources of PCB contamination. The investigation included freeze-drying of the dry RS in five different laboratories, exposure to the air in the freeze-drying room, storage at room temperature and air-drying in a certain fume hood and in a laminar flow clean bench. The pattern and concentrations of PCBs detected in the exposed RS were strongly influenced by low chlorinated PCB congeners under all of these conditions with exception for air-drying in the fume hood. Storage in the laboratory air resulted in a slight elevation in the concentrations of low chlorinated PCB congeners, whereas higher concentrations of all PCB congeners were observed after freeze-drying. In all experiments the contamination appeared to be due to adsorption of PCB from the laboratory air. On the basis of these findings we recommend that reference material be subjected to the entire procedure, including sample preparation, in order to monitor contamination and that a procedure involving solvent extraction of wet sediment samples is used, whenever possible, instead of procedures involving dry samples.

Up regulation of cathepsin K expression in articular chondrocytes in a transgenic mouse model for osteoarthritis

OBJECTIVES

To study the expression of cysteine proteinases, particularly cathepsin K, and their extracellular inhibitor cystatin C in articular cartilage of transgenic Del1 mice which harbour a short deletion mutation in a type II collagen transgene and are predisposed to early onset osteoarthritis.

METHODS

Northern analysis was used to measure mRNA levels of cathepsins B, H, K, L, and S, and cystatin C in total RNA extracted from knee joints of Del1 mice, using their non-transgenic litter mates as controls. Immunohistochemistry and morphometry was used to study the distribution of cathepsin K and cystatin C in the knee joints.

RESULTS

Up regulation of cathepsin K mRNA expression was seen in the knee joints of transgenic Del1 mice at the onset of cartilage degeneration. Cathepsin K was found near sites of matrix destruction in articular chondrocytes, particularly in clusters of proliferating cells, and in calcified cartilaginous matrix. In intact articular cartilage of control animals, cathepsin K was only seen in a small number of chondrocytes. Upon aging, control animals also developed osteoarthritis, which was accompanied by increased cathepsin K expression. Cystatin C was mostly localised in and around chondrocytes located in calcified cartilage, with no obvious association with the onset of cartilage degeneration.

CONCLUSION

The temporospatial distribution of cathepsin K in osteoarthritic cartilage suggests a role for this enzyme in the pathogenesis of osteoarthritis. Because cathepsin K can digest cartilage matrix components it may contribute to the development of osteoarthritic lesions. These data may provide new clues for the development of treatments aimed at preventing cartilage degeneration.

Multiple sclerosis: rationale for early treatment

MS often presents as acute unilateral optic neuritis (ON). While it is clear that many patients with ON suffer from a generalized disease of the central nervous system that will go on to clinically definite MS (CDMS), it is also clear that others do not. As patients become increasingly wellinformed and with the development of effective pharmacotherapy for MS, the distinction between those patients with ON who have MS and those who do not has become ever more important. Recent randomized clinical trials in patients with ON or other clinically isolated syndromes (CIS) suggestive of MS and evidence of prior subclinical demyelination on magnetic resonance imaging of the brain found that treatment with recombinant interferon-beta-1a is beneficial in reducing the development of CDMS. Ophthalmologists and other non-neurologists should refer patients with acute ON or other CIS suggestive of MS to a neurologist for MS-directed investigations.

Multiple sclerosis: a study of chemokine receptors and regulatory T cells in relation to MRI variables

Magnetic resonance imaging (MRI) remains the most valuable tool for monitoring disease activity and progression in patients with multiple sclerosis (MS), a chronic demyelinating disease of the central nervous system (CNS) with presumably autoimmune etiology. Chemokine receptors have been implicated in MS as key molecules directing inflammatory cells into the CNS. Regulatory (CD4+CD25+) T cells (Tr cells) are important in suppressing autoimmunity, and their absolute or functional deficit could be expected in MS. In the present study, venous blood was obtained from MS patients concurrent with MRI examination of the brain, and expression of chemokine receptors CCR1, CCR2, CCR5, CXCR3 and CXCR4 by CD4 T cells and monocytes, proportions of Tr cells, as well as expression of CD45RO, CD95, CTLA-4, HLA-DR and interleukin (IL)-10 by Tr cells and non-Tr (CD25-) CD4 T cells was analyzed by flow cytometry. Surface expression of CXCR3 by CD4 T cells was downregulated in the group of patients with high lesion load (LL) on T2-weighted images and gadolinium (Gd)-enhancing lesions on T1-weighted images, compared to the group with high LL and no Gd-enhancing lesions, and to the group with low LL, suggesting internalization of CXCR3 due to the release of its chemokine ligand (IP-10/CXCL10) from active MS lesions. Proportions of Tr cells amongst all CD4 T cells, and expression of IL-10 by Tr cells were increased in the patients with high LL and Gd-enhancing lesions. These results suggest that there is correlation between MRI parameters, chemokine receptor expression and the status of circulating Tr cells in MS, but further studies need to discriminate between pathogenetically relevant and bystander phenomena.

Differential recruitment of the coactivator proteins CREB-binding protein and steroid receptor coactivator-1 to peroxisome proliferator-activated receptor gamma/9-cis-retinoic acid receptor heterodimers by ligands present in oxidized low-density lipoprotein

Peroxisome proliferator-activated receptor gamma (PPARgamma) colocalizes with oxidized low-density lipoprotein (LDL) in foam cells in atherosclerotic lesions. We have explored a potential role of oxidized fatty acids in LDL as PPARgamma activators. LDL from patients suffering from intermittent claudication due to atherosclerosis was analyzed using HPLC and gas chromatography/mass spectrophotometry and found to contain 9-hydroxy and 13-hydroxyoctadecadienoic acid (9- and 13-HODE), as well as 5-hydroxy-, 12-hydroxy- and 15-hydroxyeicosatetraenoic acid (5-, 12- and 15-HETE respectively). PPARgamma was potently activated by 13(S)-HODE and 15(S)-HETE, as judged by transient transfection assays in macrophages or CV-1 cells. 5(S)- and 12(S)-HETE as well as 15-deoxy-Delta(12,14)-prostaglandin J(2) also activated PPARgamma but were less potent. Interestingly, the effect of the lipoxygenase products 13(S)-HODE and 15(S)-HETE as well as of the drug rosiglitazone were preferentially enhanced by the coactivator CREB-binding protein, whereas the effect of the cyclooxygenase product 15-deoxy-Delta(12,14)-prostaglandin J(2) was preferentially enhanced by steroid receptor coactivator-1. We interpret these results, which may have relevance to the pathogenesis of atherosclerosis, to indicate that the lipoxygenase products on the one hand and the cyclooxygenase product on the other exert specific effects on the transcription of target genes through differential coactivator recruitment by PPARgamma/9-cis retinoic acid receptor heterodimer complexes.

Predicting multiple sclerosis at optic neuritis onset

Using multivariate analyses, individual risk of clinically definite multiple sclerosis (CDMS) after monosymptomatic optic neuritis (MON) was quantified in a prospective study with clinical MON onset during 1990-95 in Stockholm, Sweden. During a mean follow-up time of 3.8 years, the presence of MS-like brain magnetic resonance imaging (MRI) lesions and oligoclonal immunoglobulin (Ig) G bands in cerebrospinal fluid (CSF) were strong prognostic markers of CDMS, with relative hazard ratios of 4.68 [95% confidence interval (CI) 2.21-9.91] and 5.39 (95% CI 1.56-18.61), respectively. Age and season of clinical onset were also significant predictors, with relative hazard ratios of 1.76 (95% CI 1.02-3.04) and 2.21 (95% CI 1.13-3.98), respectively. Based on the above two strong predictors, individual probability of CDMS development after MON was calculated in a three-quarter sample drawn from a cohort, with completion of follow-up at three years. The highest probability, 0.66 (95% CI 0.48-0.80), was obtained for individuals presenting with three or more brain MRI lesions and oligoclonal bands in the CSF, and the lowest, 0.09 (95% CI 0.02-0.32), for those not presenting with these traits. Medium values, 0.29 (95% CI 0.13-0.53) and 0.32 (95% CI 0.07-0.73), were obtained for individuals discordant for the presence of brain MRI lesions and oligoclonal bands in the CSF. These predictions were validated in an external one-quarter sample.

Cerebrospinal fluid affects phenotype and functions of myeloid dendritic cells

Myeloid (CD11c+) dendritic cells (DC) are present in cerebrospinal fluid (CSF), as well as in the meninges and choroid plexus. Functional studies of these DC are hindered or impossible. To obviate this problem, we investigated the effects of CSF supernatants from patients with non-inflammatory neurological diseases (NIND), multiple sclerosis (MS), bacterial meningitis (BM) and Lyme meningoencephalitis (LM) on immature monocyte-derived DC (moDC) from healthy donors. CSF supernatants caused maturation of moDC (MS > LM > NIND > BM), as reflected by a decrease in CD1a, and an increase in HLA-DR, CD80 and CD86 expression. The maturation effect of MS CSF and LM CSF could be blocked by anti-TNF-alpha MoAb or recombinant human IL-10. moDC cultured with BM CSF either remained immature or turned into CD14+ macrophage-like cells and were relatively inefficient at inducing T cell responses in vitro. In contrast, moDC cultured with LM CSF induced strong Th1 responses. Both BM CSF and LM CSF contained IFN-gamma, a cytokine that augments IL-12 production by moDC and hence should confer an ability to induce a Th1 response. However, BM CSF also contained high levels of IL-10, which could antagonize the effects of IFN-gamma on moDC. moDC cultured with MS CSF induced a higher production of IFN-gamma from T cells compared to moDC cultured with NIND CSF or BM CSF. In summary, soluble factors present in the CSF may influence the phenotype and functions of meningeal, choroid plexus and CSF DC which, in turn, may have an impact on the character of intrathecal T cell responses.

Multiple MAG peptides are recognized by circulating T and B lymphocytes in polyneuropathy and multiple sclerosis

Abnormal immune responses to myelin associated glycoprotein (MAG), a component of myelin of the central and peripheral nervous system, have been suggested to play a role in the pathogenesis of multiple sclerosis (MS) and certain types of inflammatory polyneuropathy. To identify possible immunodominant MAG peptides in neuroinflammation, we examined T and B cell responses to five selected synthetic MAG peptides and myelin proteins in 21 patients with non-inflammatory polyneuropathy, 26 patients with MS, 10 optic neuritis patients and 17 healthy subjects. Enzyme-linked immunosorbent spot-forming cell assays were adopted, allowing the detection and enumeration of individual antigen responsive T and B cells in body fluids. Patients with polyneuropathy as well as those with MS had elevated levels of T and B cells recognizing MAG and its peptides. Any of the five MAG peptides under study functioned as immunodominant T and/or B cell epitope in individual subjects. None of the MAG peptides elicited a specific disease-associated T or B cell response. The enhanced T and B cell response to myelin components like MAG may play some role in initiation and/or progression of these diseases, but they could also represent secondary responses associated with myelin damage and indicate tolerization rather than autoaggressive immunity.