Incidence of small lymph node metastases with evidence of extracapsular extension: clinical implications in patients with head and neck squamous cell carcinoma

Small lymph nodes (LN) show evidence of extracapsular extension (ECE) in a significant number of patients. This study was performed to determine the impact of ECE in LN 7 mm as compared with ECE in larger LN.

Cloning of farm animals: impact on animal health and welfare and implications in trade

The commercial use of animal cloning for breeding food producing animals has been limited so far by biological and technical constraints such as adverse effects on the health and welfare of animals, especially high perinatal and postnatal disease and mortality of clones. However, the improvement of the technique may overcome those problems in future and contribute to the spread of cloning in agricultural production, which raises concern not only on health and welfare aspects but also on food safety and ethics. This may cause conflict in international trade. The present article reviews these topics on the basis of up-to-date scientific opinions.

A novel mechanism for hypofibrinolysis in diabetes: the role of complement C3

Impaired fibrin clot lysis is a key abnormality in diabetes and complement C3 is one protein identified in blood clots. This work investigates the mechanistic pathways linking C3 and hypofibrinolysis in diabetes using ex vivo/in vitro studies.

Differential release of plasminogen activator inhibitors (PAIs) during dual perfusion of human placenta: implications in preeclampsia

Plasminogen activator inhibitors (PAIs) play critical roles in regulating cellular invasion and fibrinolysis. An increase in the ratio of PAI-1/PAI-2 in placenta and maternal serum is suggested to result in excessive intervillous fibrin deposition and placental infarction in pregnancies complicated by preeclampsia (PE) and intrauterine growth restriction (IUGR). In the current study we used dual (maternal and fetal) perfusion of human term placentas to examine the release of PAIs to the intervillous space. ELISA revealed a significant time-dependent increase in total PAI-1 levels in maternal perfusate (MP) between 1 and 7h of perfusion. Conversely, PAI-2 levels decreased resulting in a 3-fold increase in the PAI-1/PAI-2 ratio in MP. Levels of PAI-1, but not PAI-2, in placental tissue extracts increased during perfusion. In perfusions carried out with xanthine and xanthine oxidase (X + XO), compounds used to generate reactive oxygen species (ROS), no time-dependent increase in total PAI-1 levels was observed. In addition, X + XO treatment promoted a 3-fold reduction in active PAI-1 levels in MP, indicating that ROS decrease PAI-1 release to MP. The finding of a time-dependent change in patterns of PAI expression and response to ROS indicates the utility of dual perfusion as a model to dissect mechanism(s) promoting aberrant fibrinolysis in pregnancies complicated by PE and IUGR.

Proteolytic processing of chemokines: implications in physiological and pathological conditions

Chemokines are small, secreted proteins that orchestrate the migration of cells, which are involved in immune defence, immune surveillance and haematopoiesis. However, chemokines are also implicated in the pathology of various inflammatory diseases, cancers and HIV. The chemokine system is considerably large and has a redundancy in the repertoire of its inflammatory mediators. Therefore, strict regulation of chemokine activity is crucial. Chemokines are the substrate for various proteases including the serine protease CD26/dipeptidyl-peptidase IV and matrix metalloproteinases. Regulation by proteolytic cleavage controls and fine-tunes chemokine function by either enhancing or reducing its chemotactic activity or receptor selectivity. Often chemokines and the proteases that regulate them are produced in the same microenvironment and expression of both may be simultaneously induced by a common stimulus enabling the rapid regulation of chemokine activity. The overall impact of cleaved chemokines in cellular responses is very complex. In this review, we will give an overview on chemokine modification and the respective chemokine modifying proteases. Furthermore, we will summarize the emerging literature describing the consequences in inflammation, haematopoiesis, cancer and HIV infection upon proteolytic chemokine processing.

Microalbuminuria in diabetes mellitus: efficacy of a new screening method in comparison with timed overnight urine collection

Diabetic nephropathy and end-stage renal failure are still a major cause of mortality amongst patients with diabetes mellitus (DM). In this study, we evaluated the Clinitek-Microalbumin (CM) screening test strip for the detection of microalbuminuria (MA) in a random morning spot urine in comparison with the quantitative assessment of albuminuria in the timed overnight urine collection ("gold standard"). One hundred thirty-four children, adolescents, and young adults with insulin-dependent DM Type 1 were studied at 222 outpatient visits. Because of urinary tract infection and/or haematuria, the data of 13 visits were excluded. Finally, 165 timed overnight urine were collected in the remaining 209 visits (79% sample per visit rate). Ten (6.1%) patients presented MA of > or =15 microg/min. In comparison however, 200 spot urine could be screened (96% sample/visit rate) yielding a significant increase in compliance and screening rate (P<.001, McNemar test). Furthermore, at 156 occasions, the gold standard and CM could be directly compared. The sensitivity and the specificity for CM in the spot urine (cut-off > or =30 mg albumin/l) were 0.89 [95% confidence interval (CI) 0.56-0.99] and 0.73 (CI 0.66-0.80), respectively. The positive and negative predictive value were 0.17 (CI 0.08-0.30) and 0.99 (CI 0.95-1.00), respectively. Considering CM albumin-to-creatinine ratio, the results were poorer than with the albumin concentration alone. Using CM instead of quantitative assessment of albuminuria is not cost-effective (35 US dollars versus 60 US dollars/patient/year). In conclusion, to exclude MA, the CM used in the random spot urine is reliable and easy to handle, but positive screening results of > or =30 mg albumin/l must be confirmed by analyses in the timed overnight collected urine. Although the screening compliance is improved, in terms of analysing random morning spot urine for MA, we cannot recommend CM in a paediatric diabetic outpatient setting because the specificity is far too low.

Livelihoods in Transition: Changing Land Use Strategies and Ecological Implications in a Post Soviet Setting (Kyrgyzstan)

The sudden independence of Kyrgyzstan from the Soviet Union in 1991 led to a total rupture of industrial and agricultural production. Based on empirical data, this study seeks to identify key land use transformation processes since the late 1980s, their impact on people's livelihoods and the implication for natural resources in the communes of Tosh Bulak and Saz, located in the Sokuluk River Basin on the northern slope of the Kyrgyz Range. Using the concept of the sustainable livelihood approach as an analytical framework, three different livelihood strategies were identified: (1) An accumulation strategy applied by wealthy households where renting and/or buying of land is a key element; they are the only household category capable of venturing into rain fed agriculture. (2) A preserving strategy involving mainly intermediate households who are not able to buy or rent additional agricultural land; very often they are forced to return their land to the commune or sell it to wealthier households. (3) A coping strategy including mainly poor households consisting of elderly pensioners or headed by single mothers; due to their limited labour and economic power, agricultural production is very low and hardly covers subsistence needs; pensions and social allowances form the backbone of these livelihoods. Ecological assessments have shown that the forage productivity of remote high mountain pastures has increased from 5 to 22 per cent since 1978. At the same time forage productivity on pre-mountain and mountain pastures close to villages has generally decreased from 1 to 34 per cent. It seems that the main avenues for livelihoods to increase their wealth are to be found in the agricultural sector by controlling more and mainly irrigated land as well as by increasing livestock. The losers in this process are thus those households unable to keep or exploit their arable land or to benefit from new agricultural land. Ensuring access to land for the poor is therefore imperative in order to combat rural poverty and socio-economic disparities in rural Kyrgyzstan.

Study of the cellular mechanism of Sunitinib mediated inactivation of activated hepatic stellate cells and its implications in angiogenesis

The development of hepatocellular carcinomas from malignant hepatocytes is frequently associated with intra- and peritumoral accumulation of connective tissue arising from activated hepatic stellate cells (HSC). Inhibition of receptor tyrosine kinase (RTK) signaling showed promise in the treatment of hepatocellular carcinoma. However, there is a lack of knowledge about the effects of RTK inhibitors on the tumor supportive cells. We performed in vitro experiments to study whether Sunitinib, a platelet-derived growth factor (PDGF) and vascular endothelial growth factor (VEGF) RTKs' inhibitor, could block both activated HSC functions and angiogenesis and thus prevent the progression of cirrhotic liver to hepatocellular carcinoma. In immortalized human activated HSC LX-2, treatment with Sunitinib 100 nM blocked collagen synthesis by 47%, as assessed by Sirius Red staining, attenuated HSC contraction by 65%, and reduced cell migration by 28% as evaluated using a Boyden's chamber, without affecting cell viability, measured by Trypan blue staining, and apoptosis, measured by propidium iodide (PI) incorporation assay. Our data revealed that Sunitinib treatment blocked the transdifferentiation of primary human HSC (hHSC) to activated myofibroblast-like cells by 65% without affecting hHSC apoptosis and migration. In in vitro angiogenic assays, Sunitinib 100 nM reduced endothelial cells (EC) ring formation by 46% and tube formation by 68%, and decreased vascular sprouting in aorta ring assay and angiogenesis in vascular bed of chick embryo. In conclusion, the present study demonstrates that the RTK inhibitor Sunitinib blocks the activation of HSC and angiogenesis suggesting its potential as a drug candidate in pathological conditions like liver fibrosis and hepatocellular carcinoma.

Genome-wide Association Studies Identify Genetic Loci Associated with Albuminuria in Diabetes

Elevated concentrations of albumin in the urine, albuminuria, are a hallmark of diabetic kidney disease and associate with increased risk for end-stage renal disease and cardiovascular events. To gain insight into the pathophysiological mechanisms underlying albuminuria, we conducted meta-analyses of genome-wide association studies and independent replication in up to 5,825 individuals of European ancestry with diabetes mellitus and up to 46,061 without diabetes, followed by functional studies. Known associations of variants in CUBN, encoding cubilin, with the urinary albumin-to-creatinine ratio (UACR) were confirmed in the overall sample (p=2.4*10(-10)). Gene-by-diabetes interactions were detected and confirmed for variants in HS6ST1 and near RAB38/CTSC. SNPs at these loci demonstrated a genetic effect on UACR in individuals with but not without diabetes. The change in average UACR per minor allele was 21% for HS6ST1 and 13% for RAB38/CTSC (p=6.3*10(-7) and 5.8*10(-7), respectively). Experiments using streptozotocin-treated diabetic Rab38 knockout and control rats showed higher urinary albumin concentrations and reduced amounts of megalin and cubilin at the proximal tubule cell surface in Rab38 knockout vs. control rats. Relative expression of RAB38 was higher in tubuli of patients with diabetic kidney disease compared to controls. The loci identified here confirm known and highlight novel pathways influencing albuminuria.

Treatment Goals in Diabetes.

The quality of glycaemic control in diabetes mellitus relies on accurate individualization of available treatment options. Treatment targets depend on the type and duration of diabetes, the patients' abilities and characteristics and the individual risk for acute and/or late-stage complications. These complications include hypoglycaemia, which can be severe and life threatening, hyperglycaemia, which is a main factor for the development of cardiovascular disease, and macrovascular and microvascular disease, both of which are hallmark features of diabetes-associated constraints. Moreover, other treatment goals in diabetic patients influence both glycaemic control and quality of life. Lipoproteins, blood pressure, weight control, mental health and lifestyle are important factors that contribute to the frequency of diabetes-associated complications.

[Treatment of hypertension in type 2 diabetes mellitus--2002 update]

Arterial hypertension and diabetes are potent independent risk factors for cardiovascular, cerebral, renal and peripheral (atherosclerotic) vascular disease. The prevalence of hypertension in diabetic individuals is approximately twice that in the non-diabetic population. Diabetic individuals with hypertension have a greater risk of macrovascular and microvascular disease than normotensive diabetic individuals. Hypertension is a major contributor to morbidity and mortality in diabetes, and should be recognized and treated early. Type 2 diabetes and hypertension share certain risk factors such as overweight, visceral obesity, and possibly insulin resistance. Life-style modifications (weight reduction, exercise, limitation of daily alcohol intake, stop smoking) are the foundation of hypertension and diabetes management as the definitive treatment or adjunctive to pharmacological therapy. Additional pharmacological therapy should be initiated when life-style modifications are unsuccessful or hypertension is too severe at the time of diagnosis. All classes of antihypertensive drugs are effective in controlling blood pressure in diabetic patients. For single-agent therapy, ACE-inhibitors, angiotensin receptor blocker, beta-blockers, and diuretics can be recommended. Because of concerns about the lower effectiveness of calcium channel blockers in decreasing coronary events and heart failure and in reducing progression of renal disease in diabetes, it is recommended to use these agents as second-line drugs for patients who cannot tolerate the other preferred classes or who require additional agents to achieve the target blood pressure. The choice depends on the patients specific treatment indications since each of these drugs have potential advantages and disadvantages. In patients with microalbuminuria or clinical nephropathy, both ACE-inhibitors and angiotensin receptor blockers are considered first line therapy for the prevention of and progression of nephropathy. Since treatment is usually life-long, cost effectiveness should be included in treatment evaluation.

Impaired vascular function in normoglycemic mice prone to autoimmune diabetes: role of nitric oxide

Type 1 diabetes is an immuno-inflammatory condition which increases the risk of cardiovascular disease, particularly in young adults. This study investigated whether vascular function is altered in mice prone to autoimmune diabetes and whether the nitric oxide (NO)-cyclic GMP axis is involved. Aortic rings suspended in organ chambers and precontracted with phenylephrine were exposed to cumulative concentrations of acetylcholine. To investigate the role of NO, some experiments were performed in the presence of either 1400W (N-(3-aminomethyl)benzyl-acetamidine hydrochloride), a selective inhibitor of the iNOS-isoform, L-NAME (N(G)-nitro-L-arginine methyl ester hydrochloride), an inhibitor of all three NOS-isoforms, or ODQ (1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one), a selective inhibitor of guanylate cyclase. Moreover, contractility to phenylephrine, big endothelin-1, and endothelin-1 was assessed and histological analysis and iNOS immunohistochemistry were performed. Endothelium-dependent relaxation was reduced in prediabetic NOD mice (78+/-4 vs. 88+/-2%, respectively, P<0.05 vs. control) despite normal plasma glucose levels (n.s. vs. control). Preincubation with 1400W further attenuated responses in prediabetic (P<0.05 vs. untreated) but not in diabetic or in control mice. In contrast, basal NO bioactivity remained unaffected until the onset of diabetes in NOD mice. Contractile responses to big endothelin-1 and endothelin-1 were reduced in prediabetic animals (P<0.05 vs. control), whereas in diabetic mice only responses to big endothelin-1 were decreased (P<0.05 vs. control). These data demonstrate that endothelium-dependent and -independent vascular function in NOD mice is abnormal already in prediabetes in the absence of structural injury. Early proinflammatory activation due to iNOS in diabetes-prone NOD mice appears to be one of the mechanisms contributing to impaired vasoreactivity.

Glycemic control and macrovascular disease in types 1 and 2 diabetes mellitus: Meta-analysis of randomized trials

Uncertainty persists concerning the effect of improved long-term glycemic control on macrovascular disease in diabetes mellitus (DM).