The 100 Most-Cited Articles Focused on Ultrasound Imaging: A Bibliometric Analysis.

Purpose The number of citations that an article has received reflects its impact on a particular research area. The aim of this study was to identify the 100 most-cited articles focused on ultrasound (US) imaging and to analyze the characteristics of these articles. Methods We determined the 100 most-cited articles on US imaging via the Web of Science database, using the search term. The following parameters were used to analyze the characteristics of the 100 most-cited articles: publication year, journal, journal impact factor, number of citations and annual citations, authors, department, institution, country, type of article, and topic. Results The number of citations for the 100 most-cited articles ranged from 1849 to 341 (median: 442.0) and the number of annual citations ranged from 108.0 to 8.1 (median: 22.1). The majority of articles were published in 1990 - 1999 (39 %), published in radiology journals (20 %), originated in the United States (45 %), were clinical observation studies (67 %), and dealt with the vessels (35 %). The Department of Internal Medicine at the University of California and the Research Institute of Public Health at the University of Kuopio (n = 4 each) were the leading institutions and Salonen JT and Salonen R (n = 4 each) were the most prolific authors. Conclusion Our study presents a detailed list and analysis of the 100 most-cited US articles, which provides a unique insight into the historical development in this field.

Sodium meta-arsenite prevents the development of autoimmune diabetes in NOD mice.

Sodium meta-arsenite (SA) is an orally available arsenic compound. We investigated the effects of SA on the development of autoimmune type 1 diabetes. Female non-obese diabetic (NOD) mice were orally intubated with SA (5mg/kg/day) from 8weeks of age for 8weeks. The cumulative incidence of diabetes was monitored until 30weeks of age, islet histology was examined, and lymphocytes including T cells, B cells, CD4+ IFN-γ+ cells, CD8+ IFN-γ+ cells, CD4+ IL-4+ cells, and regulatory T cells were analyzed. We also investigated the diabetogenic ability of splenocytes using an adoptive transfer model and the effect of SA on the proliferation, activation, and expression of glucose transporter 1 (Glut1) in splenocytes treated with SA in vitro and splenocytes isolated from SA-treated mice. SA treatment decreased the incidence of diabetes and delayed disease onset. SA treatment reduced the infiltration of immunocytes in islets, and splenocytes from SA-treated mice showed a reduced ability to transfer diabetes. The number of total splenocytes and T cells and both the number and the proportion of CD4+ IFN-γ+ and CD8+ IFN-γ+ T cells in the spleen were significantly reduced in SA-treated NOD mice compared with controls. The number, but not the proportion, of regulatory T cells was decreased in SA-treated NOD mice. Treatment with SA either in vitro or in vivo inhibited proliferation of splenocytes. In addition, the expression of Glut1 and phosphorylated ERK1/2 was decreased by SA treatment. These results suggest that SA reduces proliferation and activation of T cells, thus preventing autoimmune diabetes in NOD mice.

Glucagon-like peptide-1 inhibits adipose tissue macrophage infiltration and inflammation in an obese mouse model of diabetes.

AIMS/HYPOTHESIS: Obesity and insulin resistance are associated with low-grade chronic inflammation. Glucagon-like peptide-1 (GLP-1) is known to reduce insulin resistance. We investigated whether GLP-1 has anti-inflammatory effects on adipose tissue, including adipocytes and adipose tissue macrophages (ATM). METHODS: We administered a recombinant adenovirus (rAd) producing GLP-1 (rAd-GLP-1) to an ob/ob mouse model of diabetes. We examined insulin sensitivity, body fat mass, the infiltration of ATM and metabolic profiles. We analysed the mRNA expression of inflammatory cytokines, lipogenic genes, and M1 and M2 macrophage-specific genes in adipose tissue by real-time quantitative PCR. We also examined the activation of nuclear factor κB (NF-κB), extracellular signal-regulated kinase 1/2 and Jun N-terminal kinase (JNK) in vivo and in vitro. RESULTS: Fat mass, adipocyte size and mRNA expression of lipogenic genes were significantly reduced in adipose tissue of rAd-GLP-1-treated ob/ob mice. Macrophage populations (F4/80(+) and F4/80(+)CD11b(+)CD11c(+) cells), as well as the expression and production of IL-6, TNF-α and monocyte chemoattractant protein-1, were significantly reduced in adipose tissue of rAd-GLP-1-treated ob/ob mice. Expression of M1-specific mRNAs was significantly reduced, but that of M2-specific mRNAs was unchanged in rAd-GLP-1-treated ob/ob mice. NF-κB and JNK activation was significantly reduced in adipose tissue of rAd-GLP-1-treated ob/ob mice. Lipopolysaccharide-induced inflammation was reduced by the GLP-1 receptor agonist, exendin-4, in 3T3-L1 adipocytes and ATM. CONCLUSIONS/INTERPRETATION: We suggest that GLP-1 reduces macrophage infiltration and directly inhibits inflammatory pathways in adipocytes and ATM, possibly contributing to the improvement of insulin sensitivity.

CFD modelling of flow field and particle tracking in a hydrodynamic stormwater separator.

The best management practices (BMPs) for control of urban stormwater pollution are evaluated to remove solid particles containing various pollutants. Currently, most storm runoff treatment devices using primary pollutant removal mechanism are applied to storm water since most pollutants in runoff are associated with the solid particulates. A hydrodynamic separator is a storm water treatment device using centrifugal motion which separates solids pollution from runoff. In this study, the velocity flow field and particle tracking of hydrodynamic separator were investigated using anthracite as a computational fluid dynamics (CFD) model particle. The Fluent 6.3.26 CFD program was used to predict the solid particles removal efficiency for various parameters such as particle size, surface loading rate, and the ratio of underflow to overflow. The velocity flow field in a hydrodynamic stormwater separator (HDS) has been simulated using CFD RNG κ-ε model. Modeling results for the removal efficiency of HDS were similar with the results obtained from experimental measurements of laboratory scale HDS. These results showed that the simulated velocity field was useful to interpret the behavior of flow in the hydrodynamic separator. The results obtained from particle tracking can be applied to predict the separation efficiency.

Detection and characterization of intracranial aneurysms with 16-channel multidetector row CT angiography: a prospective comparison of volume-rendered images and digital subtraction angiography.

BACKGROUND AND PURPOSE: The aim of our study was to compare multidetector row CT angiography (MDCTA) with digital subtraction angiography (DSA) in the detection and characterization of intracranial aneurysms. MATERIALS AND METHODS: In our blinded prospective study, 85 patients with suspected intracranial aneurysm (47 women, 38 men; age range, 19-83 years) underwent both 16-channel MDCTA and DSA. The MDCT angiograms were interpreted for the presence, location, size, ratio of the neck to the dome (N/D ratio), and lobularity of the aneurysms and relationship of the aneurysm with the adjacent arterial branches, by using volume-rendering techniques. MDCTA and DSA images (reference standard) were interpreted by 2 independent readers, and the results were compared. RESULTS: A total of 93 aneurysms were detected at DSA in 71 patients, whereas no aneurysms were detected in 14 patients. Compared with DSA, the overall sensitivity, specificity, and accuracy of MDCTA on a per-aneurysm basis were 92.5%, 93.3%, and 92.6%, respectively, for both independent readers. For aneurysms of <3 mm, however, MDCTA had a sensitivity of 74.1% for reader 1 and 77.8% for reader 2. There was excellent agreement between readers in the detection of aneurysms (kappa = 0.822). In addition, MDCTA was also accurate in determining N/D ratio of aneurysms, aneurysm lobularity, and adjacent arterial branches. CONCLUSION: MDCTA is accurate in the detection and characterization of intracranial aneurysms and can be used as a reliable alternative imaging technique to DSA in selected cases.

Multidetector-row CT angiography of cerebral vasospasm after aneurysmal subarachnoid hemorrhage: comparison of volume-rendered images and digital subtraction angiography.

BACKGROUND AND PURPOSE: Cerebral vasospasm remains a major problem in patients recovering after surgical treatment of cerebral aneurysms. The purpose of this study was to evaluate cerebral vasospasm at multidetector-row spiral CT angiography (MDCTA) compared with digital subtraction angiography (DSA) in patients with aneurysmal subarachnoid hemorrhages (SAHs). METHODS: Seventeen patients suspected of having vasospasm on clinical findings underwent both postoperative MDCTA and DSA. MDCTA was analyzed by using volume-rendered images as well as axial images. A total of 251 arterial segments were analyzed for vasospasm by using a 5-point grading system. The MDCTA results were then compared with findings on the corresponding DSA images. Sensitivity, specificity, and accuracy of MDCTA for detection of hemodynamically significant spasms were also calculated, with findings at DSA used as the reference standard. RESULTS: On DSA, 74 spasmatic segments were found among the 251 segments evaluated, and 40 segments with hemodynamically significant vasospasms were present. The overall agreement between MDCTA and DSA was 95.2%. We had 12 (4.8%) cases of disagreement between MDCTA and DSA. In 11 segments, the degree of stenosis was overestimated at MDCTA. Overall accuracy, sensitivity and specificity of MDCTA in the detection of hemodynamically significant vasospasm were 97.5%, 98.1%, and 98.0%, respectively, with positive and negative predictive values of 90.7% and 99.5%. CONCLUSION: MDCTA appears to be a reliable alternative imaging technique to DSA in the assessment of patients with cerebral vasospasm after aneurysmal SAH.

Free fatty acids induce peripheral insulin resistance without increasing muscle hexosamine pathway product levels in rats.

To evaluate the role of the hexosamine biosynthesis pathway (HBP) in fat-induced insulin resistance, we examined whether fat-induced insulin resistance is additive to that induced by increased HBP flux via glucosamine infusion and, if so, whether such additive effects correlate with muscle HBP product levels. Prolonged hyperinsulinemic (approximately 550 pmol/l) euglycemic clamps were conducted in conscious overnight-fasted rats. After the initial 150 min to attain steady-state insulin action, rats received an additional infusion of saline, Intralipid, glucosamine, or Intralipid and glucosamine (n = 8 or 9 for each) for 330 min. At the conclusion of clamps, skeletal muscles (soleus, extensor digitorum longus, and tibialis anterior) were taken for the measurement of HBP product levels. Intralipid and glucosamine infusions decreased insulin-stimulated glucose uptake (Rd) by 38 and 28%, respectively. When the infusions were combined, insulin-stimulated Rd decreased 47%, significantly more than with Intralipid or glucosamine alone (P < 0.05). The glucosamine-induced insulin resistance was associated with four- to fivefold increases in muscle HBP product levels. In contrast, the Intralipid-induced insulin resistance was accompanied by absolutely no increase in HBP product levels in all of the muscles examined. Also, when infused with glucosamine, Intralipid decreased insulin action below that with glucosamine alone without changing HBP product levels. In a separate study, short-term (50 and 180 min) Intralipid infusion also failed to increase muscle HBP product levels. In conclusion, increased availability of plasma free fatty acids induces peripheral insulin resistance without increasing HBP product levels in skeletal muscle.

Differential infection of porcine alveolar macrophage subpopulations by nonopsonized Mycobacterium bovis involves CD14 receptors.

The resurgence in mycobacterial infection worldwide has led to renewed attention to the pathogenesis of Mycobacterium species. The purpose of this study was to characterize the infection of alveolar macrophages (AMs) by nonopsonized Mycobacterium bovis, and to elucidate the mechanism by which a differential infection of subpopulations of AM may occur. A difference in susceptibility to Mycobacterium bovis infection of subpopulations of AMs was observed, such that the least dense cells were the least susceptible (21.4 +/- 10.7%) and the most dense cells were the most readily infected (61.8 +/- 5.6%). The percentage of AMs staining for CD14 receptors showed a similar differential distribution, with fewer of the least dense cells expressing CD14 and a greater percentage of the most dense cells staining for CD14 receptor expression. To investigate the role of CD14 receptors in the infection of AMs, anti-CD14 antibody was added to the cell cultures. Infection of AM by Mycobacterium bovis was blocked by up to 60.2% by anti-CD14 antibody but not by isotype control antibody. The results of this study suggest that Mycobacterium bovis selectively infects AM subpopulations, specifically those with the greatest expression of CD14, a putative receptor mechanism for Mycobacterium bovis infection of porcine AM.

Benign breast diseases associated with cyclosporine therapy in renal transplant recipients.

PURPOSE: Our aim was to correlate the radiologic characteristics of cyclosporine-induced benign breast diseases with clinical and pathologic findings. MATERIALS AND METHODS: The clinical, mammographic, and ultrasonographic records of 33 female renal transplant recipients who received cyclosporine were retrospectively reviewed. Eleven patients had 46 breast masses on ultrasonography. We performed core needle biopsies on 20 masses and reviewed the pathologic findings. RESULTS: Among 33 female renal transplant recipients, 11 (33%) had 46 benign breast lesions detected on ultrasonography. We performed core needle biopsies on 20 of the 46 masses. On pathologic examination, 12 were fibroadenomas, 6 showed fibrocystic changes, and 2 revealed dense fibrosis. Regardless of the final pathologic diagnosis, more than half of the lesions revealed severe lymphatic and venular swellings. Among 11 patients with breast lesions on ultrasonography, 10/11 (91%) showed multiplicity, and 7/11 (64%) bilaterality. Mammographically, patients with breast lesions revealed heterogeneous or extremely dense breast patterns, and 8 of 11 patients, circumscribed masses. Twenty-two patients without breast lesions showed scattered fibroglandular densities (n = 7), or heterogeneously dense (n = 11) or extremely dense (n = 4) breast patterns, and 3 of 22 patients showed vague or asymmetric densities that needed further evaluation. CONCLUSION: The development of new breast lesions in patients after renal transplantation should suggest a diagnosis of cyclosporine-induced benign breast disease including fibroadenoma, fibrocystic changes, and dense fibrosis.

Involvement of different second messengers in parathyroid hormone- and interleukin-1-induced interleukin-6 and interleukin-11 production in human bone marrow stromal cells.

Previous studies have suggested that increased secretion of bone active cytokines, such as interleukin-6 (IL-6) and interleukin-11 (IL-11), from osteoblasts and stromal cells play a pivotal role in the activation of osteoclasts and the genesis of osteoporosis. Various systemic and local factors can stimulate IL-6/IL-11 production, but the intracellular mechanism for such stimulation is largely unknown. In this study, we characterized the second messenger signaling in parathyroid hormone (PTH)- and IL-1-induced production of IL-6/IL-11 and studied the possible modulating effects of estrogen. rhPTH(1-34) and rhIL-1 alpha dose-dependently stimulated IL-6 and IL-11 production from human bone marrow stromal cells (hBMSCs). Agonists for protein kinase A (PKA) (forskolin), and protein kinase C (PKC) (phorbol 12-myristate 13-acetate; PMA) also stimulated IL-6/IL-11 production. Rp-diastereoisomer of adenosine cyclic 3',5'-phosphorothioate (Rp-cAMPS) and H-8, inhibitors of PKA, significantly inhibited PTH-stimulated IL-6/IL-11 production, but did not inhibit IL-1-stimulated IL-6/IL-11 production. In contrast, staurosporine and calphostin C, inhibitors of PKC, suppressed IL-1-stimulated, but not PTH-stimulated, IL-6/ IL-11 production. Pretreatment of cells with 17 beta-estradiol (17 beta-E2) antagonized IL-1-stimulated IL-6 production. However, PTH-stimulated IL-6 production and IL-1- and PTH-stimulated IL-11 production were not affected by 17 beta-E2. Similarly, 17 beta-E2 inhibited PMA-stimulated IL-6 production, whereas neither forskolin-stimulated IL-6/ IL-11 production nor PMA-stimulated IL-11 production was affected by 17 beta-E2. These results indicate that different second messengers are involved in PTH- and IL-1-induced IL-6 and IL-11 production by hBMSCs: PTH and IL-1 stimulate IL-6/IL-11 production via a PKA-dependent and PKC-dependent pathway, respectively. Furthermore, our results suggest that regulation of cytokine production by estrogen in hBMSCs is selective; only the IL-1-induced IL-6 production, which is mediated by PKC pathway, is inhibited, but PTH-induced IL-6 production and PTH/IL-1-induced IL-11 production are not inhibited by estrogen.

A study of the correlation between organic matrices and nanocomposite materials in oyster shell formation.

Calcium carbonate minerals are an integral part of many organisms. These biogenic minerals are all of original size, shape and high strength, and they are quite different from those found in their abiotic precipitates. It has been accepted that the formation, morphological development and crystallography of the biocomposites are controlled by the intrinsic molecular recognition of macromolecules. In this study, with the analyses of X-ray diffraction and scanning electron microscopy of the texture of biogenic minerals in oyster shells, we noted that the intracrystalline proteins deliberately reduce the coherence lengths of biogenic crystals compared to synthetic ones, leading to more isotropy. In order to understand the exact nature of the controlled nucleation and growth, we investigated the changes in protein conformation in vivo from the mineral-specific layers using Fourier self-deconvolution and Gaussian curve-fitting techniques. And via in vitro assays, we studied the relation of such changes to biomineral phase and morphology. We showed that the shell proteins in vivo are in the higher structural ordered state, and beta-antiparallel structure was predominant in each shell layer. Also, as the shell undergoes a change of calcium carbonate polymorphs from aragonite to calcite, significant alterations of the protein conformation with the denaturing of alpha-helix and beta-structure in the aragonitic layer is induced. These results provide a relationship between the effects of conformational changes on the nanostructure of biocomposites and the necessity of new synthetic strategies.

Polymerase chain reaction (PCR) amplification for the detection of porcine parvovirus.

A polymerase chain reaction (PCR) amplification method was developed and evaluated to detect porcine parvovirus (PPV). A pair of 20-base primers and an oligonucleotide probe were derived from the DNA sequences common to two isolates of PPV, NADL-8 and NADL-2. The primers flanked 118-bp nucleotides within the region coding for the major structural protein VP2. After DNA amplification of PPV replicative form (RF), a 158-bp fragment was detected in agarose gels. This amplified fragment was shown to be specific for PPV DNA after Southern transfer and hybridization to a 20-base internal probe. The amplified fragment also contained a single EcoRI cleavage site. Various conditions, such as number of cycles and annealing temperature, were examined to optimize the conditions for detecting viral DNAs from infected cell cultures and swine fetal tissues. Four different isolates of PPV, NADL-8, NADL-2, KBSH and Kresse, and two other viruses, canine parvovirus (CPV) and pseudorabies virus (PRV), were included to determine specificity of amplification. Slot blot hybridization with a radiolabeled probe was used to evaluate the sensitivity of PCR amplification. The optimized protocol was specific for PPV detecting equally all four strains of PPV, but failing to amplify CPV or PRV sequences. The PCR method could detect at least 100 fg of viral replicative form (RF) DNA or the equivalent of 1 PFU of infectious virus. The applications of this method include routine detection of PPV in clinical samples and as a contaminant in mammalian cell lines.

Association between birth weight and insulin sensitivity in healthy young men in Korea: role of visceral adiposity.

Recent studies have demonstrated decreased insulin sensitivity in individuals with low birth weight. This study was performed to examine whether abdominal obesity is a link between insulin resistance and low birth weight. We studied the relationships between birth weight and insulin secretion, insulin sensitivity, and various anthropometric indices including visceral fat area in 22 healthy young Korean adults. Birth weight correlated significantly with diastolic blood pressure (r=-0.47, P<0.05) and insulin sensitivity index (S(I)) measured by a frequently sampled intravenous glucose tolerance test (FSIGT) (r=0.54, P<0.05), but not with insulin secretory indices such as acute insulin responses during FSIGT (r=-0.35, NS) or hyperglycemic clamp (r=0.17, NS) and submaximum insulin response during hyperglycemic clamp (r=0.10, NS). S(I) correlated significantly with abdominal obesity measurements such as waist circumference (r=-0.48, P<0.05), waist-to-hip ratio (r=-0.53, P<0.05) and visceral fat area (r=-0.58, P<0.01). However, we could not find significant correlation between birth weight and any of the abdominal obesity measurements (r=-0.35 for waist-to-hip ratio, r=-0.22 for visceral fat area, and r=-0.24 for visceral-to-subcutaneous fat ratio; NS for all). The present data confirm that low birth weight is associated with insulin resistance in adult life. However, our data suggest that the association between low birth weight and insulin resistance is not mediated by abdominal obesity.

Peripheral blood mitochondrial DNA content correlates with lipid oxidation rate during euglycemic clamps in healthy young men.

Both qualitative and quantitative changes in mitochondrial DNA (mtDNA) have been implicated in the pathogenesis of diabetes mellitus. It was previously found that decreased mtDNA content preceded the development of diabetes and mtDNA content correlated with the clinical parameters of insulin resistance syndrome, including diastolic blood pressure and waist-hip ratio. These results prompted one to look whether there are correlations between mtDNA content and the biochemical parameters of insulin resistance in non-diabetic subjects. MtDNA content of peripheral blood leukocytes was measured in Korean healthy young men, and this was correlated with various parameters of fuel metabolism at baseline and during euglycemic hyperinsulinemic clamps with indirect calorimetry. MtDNA content in peripheral blood leukocytes did not correlate with insulin sensitivity index or other metabolic variables such as body mass index (BMI), waist-to-hip ratio (WHR) and blood pressure. However, mtDNA content showed a positive significant correlation with fat oxidation rate during euglycemic clamps (r = 0.61, P < 0.05). Changes in fat oxidation rate and carbohydrate oxidation rate during the clamps were significantly correlated with mtDNA content (r = 0.65, P < 0.05, r = -0.65, P < 0.05, respectively). These results suggest that mtDNA content in peripheral blood may not correlate with insulin resistance per se but with some aspect of insulin resistance in healthy young men.

Peripheral blood mitochondrial DNA content is inversely correlated with insulin secretion during hyperglycemic clamp studies in healthy young men.

Abnormalities in mitochondrial DNA(mtDNA) have been implicated in the pathogenesis of diabetes mellitus. We recently reported that decreased mtDNA content precedes the development of diabetes mellitus and is associated with parameters of insulin resistance. In this study, we examined whether there is any relation between mtDNA content and insulin secretion. We compared the mtDNA content of peripheral blood leukocytes with the parameters of insulin secretion measured by hyperglycemic clamp in a group of healthy young men. There were statistically significant correlations between mtDNA content in peripheral blood and fasting plasma insulin (r=-0.43, P<0.05) and C-peptide levels (r=-0.44, P<0.05). MtDNA content also correlated negatively with acute insulin response(r=-0.48, P<0.05), late insulin response (r=-0.50, P<0.05) during hyperglycemic clamp and insulin secretion after glucagon stimulation (r=-0.60, P<0.01). mtDNA content in peripheral blood correlated negatively with homeostasis model (HOMA) insulin resistance (r=-0.45, P<0.05) although it did not correlate with the insulin insensitivity index (M/I) during hyperglycemic clamp. In summary, the mtDNA content of peripheral blood correlated negatively with indices of insulin resistance and insulin secretion in healthy young men. The compensatory response of pancreas beta cells to insulin resistance might contribute in part to increased insulin secretion in these subjects.

Microalbuminuria is associated with the insulin resistance syndrome independent of hypertension and type 2 diabetes in the Korean population.

To investigate whether microalbuminuria is associated with the insulin resistance syndrome independent of hypertension and type 2 diabetes, we studied the association between microalbuminuria and features of insulin resistance syndrome in Korean general population. We selected 1006 subjects by a random cluster sampling among residents aged >40 years living in the Chung-Up district, a rural area of South Korea. Subjects were stratified by oral glucose tolerance status [normal glucose tolerance (NGT), impaired glucose tolerance (IGT), and diabetes mellitus], and by the presence or absence of hypertension. Urinary albumin excretion rate (UAER) was determined using timed overnight urine collection. Various cardiovascular risk factors including anthropometric indices, serum lipid, true insulin and proinsulin concentrations were also measured. The prevalence of microalbuminuria (UAER between 20 and 200 microg/min) increased as the glucose tolerance worsened (6.0% in NGT, 11.8% in IGT, and 21.8% in diabetes; chi(2) trend=25.9, P<0.001). Subjects with microalbuminuria had a higher body mass index (BMI), waist-to-hip circumference ratio (WHR), systolic and diastolic blood pressure (BP), fasting and 2 h plasma glucose, fasting plasma insulin and proinsulin levels, and lower HDL-cholesterol level than subjects without microalbuminuria. In multiple regression analysis, BMI, diastolic BP, 2 h plasma glucose, and fasting plasma insulin levels were found to be independent factors associated with UAER. Multiple logistic regression analysis showed that not only diabetes mellitus and hypertension, but also fasting hyperinsulinemia and waist-to-hip ratio were independent factors associated with the presence of microalbuminuria. When the normotensive, non-diabetic subjects were analyzed separately, fasting hyperinsulinemia and impaired glucose tolerance remained independent variables associated with the presence of microalbuminuria. These results show that microalbuminuria in the Korean general population is associated with hyperinsulinemia and central obesity, and suggest that microalbuminuria is a feature of the insulin resistance syndrome independent of hypertension or type 2 diabetes.

Specificity of purified protein derivative extracts from ten species of Mycobacteria killed with phenol in the haemagglutination and haemagglutination inhibition test.

The specificity of purified protein derivative (PPD) extracts from 10 species of Mycobacteria killed with phenol was evaluated using the haemagglutinin (HA) and haemagglutination inhibition (HI) tests. The HA test showed many cross-reactions with homologous and heterologous antisera. In the HI test, many antisera cross-reacted with most PPD extracts. The PPD extracts from Mycobacterium foruitum and M. smegmatis were the most specific. It was concluded that PPD extracted from unheated bacilli was not sufficiently specific for use in HI tests.

Factors affecting the consecutive and simultaneous coupling with bis-diazotized benzidine of protein antigen to sheep red blood cells.

The dynamics of attaching antigen to sheep red blood cells using bis-diazotized benzidine ( BDB ) were studied using purified protein derivative tuberculin as antigen. Factors considered were the concentration of antigen and BDB , temperature, time, and simultaneous or consecutive coupling. Simultaneous coupling at 42 degrees C for 10 min gave the most specific haemagglutination reactions and was simple to carry out.

Colorimetric assay using XTT for assessing virulence of avian Pasteurella multocida strains.

A colorimetric assay using sodium 3,3'-[1[(phenylamino)carbonyl]3,4- tetrazolium]-bis(4-methoxy-6-nitro) benzene sulfonic acid hydrate (XTT) was adapted to quantitate bactericidal activity of chicken macrophage HD 11 cell line against five Pasteurella multocida strains and an avirulent transposon insertion mutant. The strains used were virulent P1059, and D92, and four avirulent strains including a streptomycin resistant mutant of P1059 (P1059 SmR), two live vaccine strains namely, the Clemson University (CU) and M9, and a transposon insertion mutant PmTn-294. Percentage of bacteria killed by chicken macrophage (HD 11) cells was determined by extrapolation from a standard formazan curve derived by incubating XTT with known bacterial cell numbers of each strain. The amount of formazan as measured by absorption at 450 nm was directly related to the number of viable bacterial cells. The percentages of P1059 SmR, CU, M9 and PmTn-294 killed by HD 11 cells were approximately 50%, 61%, 25% and 34%, respectively. By contrast, the virulent P1059 and D92 strains were resistant to killing, and were able to replicate inside the HD 11 cells. Association of virulence with resistance to phagocytic killing by HD 11 cells as assessed by the colorimetric bactericidal assay, was validated with resistance to complement (C')-mediated killing and a turkey mortality test. Strains P1059 and D92 were resistant to C'-mediated killing, whereas strains P1059 SmR, CU, M9 and PmTn-294 strains were susceptible. All turkeys challenged with P1059 or D92 were dead within 18 hrs. Mortality did not occur in turkeys challenged with strains of P1059 SmR, M9 and PmTn-294. The mortality among CU challenged turkeys ranged from 0 to 40%. The results suggest that the colorimetric bactericidal assay using XTT can be used to quantitate chicken macrophage phagocytic killing of P. multocida strains, and may be a valuable assay to differentiate virulent from avirulent strains of avian P. multocida.

Immunity to PRRSV: double-edged sword.

The immune system is a double-edged sword for porcine reproductive and respiratory syndrome virus (PRRSV) infection. On one edge PRRSV has a predilection for immune cells and the disease manifestations can be linked directly to changes in the immune system. PRRSV appears to replicate extensively, if not exclusively, in cells of the immune lineage, notably macrophages; the direct replication of which may lead to immunosuppression, precipitate secondary infection and/or mediate disease. On the other edge, the virus stimulates immunity post-infection that protects an animal from re-infection. A vast array of structural and functionally distinct antibody specific to PRRSV are generated following infection or vaccination. Discrete populations of functional antibodies appear at different times and possibly reflect reactivity to different PRRSV polypeptides. Cell-mediated immune responses specific to PRRSV can be detected in various exposed pigs as well. Thus, the immune system appears to be intimately involved in both the disease process and protection from disease. It is unclear at this state of understanding what immune compartment provides protective immunity. It is humoral (i.e. antibodies), selective functionally distinct populations of antibodies specific for selected PRRSV polypeptides or is cellular immunity essential for protection, or both. This review will attempt to summarize the current state of knowledge of the complex interaction of the immune system and PRRSV.