Biochemical and Serological Characteristics of a Yersinia enterocolitica Isolate

Yersinia enterocolitica was isolated from human mesenteric lymph nodes. Its morphological characteristics and biochemical and serological reactions are described.     

Inhibition of vascular endothelial growth factor (VEGF) does not affect early renal changes in a rat model of lean type 2 diabetes.

Type 2 diabetes is the most frequent cause of end-stage renal failure in many Western countries. Approximately 10-15 % of all type 2 diabetics are lean. Various growth factors and cytokines have been implicated in the pathophysiology of diabetic kidney disease, including vascular endothelial growth factor (VEGF). To elucidate a role for VEGF in the renal changes associated with type 2 diabetes, we examined the effect of a VEGF-antibody (ab) on early renal changes in the Goto-Kakizaki (GK) rat, a lean type 2 diabetes model. GK-rats were treated for 6 weeks with the VEGF-ab or with an isotype-matched irrelevant IgG. Wistar rats were used as non-diabetic controls. Placebo-treated GK-rats showed a pronounced increase in glomerular volume and urinary albumin excretion (UAE) and no change in the renal expression of endothelial nitric oxide synthase (eNOS) compared to placebo-treated non-diabetic controls. Kidney weight and creatinine clearance were no different between the groups. VEGF-ab treatment had no effect on glomerular volume, UAE, eNOS expression, body weight, blood glucose levels or food intake, but lowered serum insulin levels in non-diabetic and diabetic animals. We conclude that VEGF inhibition has minimal effects on early renal changes in GK-rats.     

Human immunodeficiency virus viremia induces plasmacytoid dendritic cell activation in vivo and diminished alpha interferon production in vitro

Human immunodeficiency virus type 1 (HIV-1) infection has been associated with perturbations of plasmacytoid dendritic cells (PDC), including diminished frequencies in the peripheral blood and reduced production of type I interferons (IFNs) in response to in vitro stimulation. However, recent data suggest a paradoxical increase in production of type 1 interferons in vivo in HIV-infected patients compared to uninfected controls. Using a flow cytometric assay to detect IFN-alpha-producing cells within unseparated peripheral blood mononuclear cells, we observed that short-term interruptions of antiretroviral therapy are sufficient to result in significantly reduced IFN-alpha production by PDC in vitro in response to CpG A ligands or inactivated HIV particles. The primary cause of diminished IFN-alpha production was reduced responsiveness of PDC to de novo stimulation, not diminished per cell IFN-alpha production or migration of cells to lymphoid organs. Real-time PCR analysis of purified PDC from patients prior to and during treatment interruptions revealed that active HIV-1 replication is associated with upregulation of type I IFN-stimulated gene expression. Treatment of hepatitis C virus-infected patients with IFN-alpha2b and ribavirin for hepatitis C virus infection resulted in a profound suppression of de novo IFN-alpha production in response to CpG A or inactivated HIV particles, similar to the response observed in HIV-infected patients. Together, these results suggest that diminished production of type I interferons in vitro by PDC from HIV-1-infected patients may not represent diminished interferon production in vivo. Rather, diminished function in vitro is likely a consequence of prior activation via type I interferons or HIV virions in vivo.     

Two families of acyl-CoA thioesterases in Arabidopsis

We have identified two families of acyl-CoA thioesterase (ACHs) in Arabidopsis thaliana. One family, consisting of AtACH1 and AtACH2, appears to be peroxisomal, as they have type-1 peroxisomal targeting sequences. The other family, consisting of AtACH4 and AtACH5, resides in the endoplasmic reticulum, as shown by green fluorescent protein studies. AtACH2 has been overexpressed in Escherichia coli and shows high levels of acyl-CoA thioesterase activity against both 16:0-CoA and 18:1-CoA. AtACH5 has also been overexpressed in E. coli, and shows thioesterase activity as well. ACHs have been characterized in other many other organisms and in various subcellular locations, but their true physiological role is not yet understood. Indeed, atach5 gene knockout mutants have no observable phenotype.     

Hyperglycemia Exacerbates Burn-Induced Liver Inflammation via Noncanonical Nuclear Factor-κB Pathway Activation

Hyperglycemia and inflammation are hallmarks of burn injury. In this study, we used a rat model of hyperglycemia and burn injury to investigate the effects of hyperglycemia on inflammatory responses in the liver. Hyperglycemia was induced in male Sprague-Dawley rats with streptozotocin (STZ) (35–40 mg/kg), followed by a 60% third-degree scald burn injury. Cytokine levels (by multiplex, in cytosolic liver extracts), hormones (by enzyme-linked immunosorbent assay [ELISA], in serum), nuclear factor (NF)-κB protein deoxyribonucleic acid (DNA) binding (by ELISA, in nuclear liver extracts) and liver functional panel (using VetScan, in serum) were measured at different time points up to 7 d after burn injury. Blood glucose significantly increased after burn injury in both groups with different temporal patterns. Hyperglycemic rats were capable of endogenous insulin secretion, which was enhanced significantly versus controls 12 h after burn injury. DNA binding data of liver nuclear extracts showed a robust and significant activation of the noncanonical NF-κB pathway in the hyperglycemic versus control burn animals, including increased NF-κB–inducing kinase expression (p < 0.05). Liver acute-phase proteins and cytokine expression were increased, whereas secretion of constitutive proteins was decreased after burn injury in hyperglycemic versus control animals (p < 0.05). These results indicate that burn injury to the skin rapidly activated canonical and noncanonical NF-κB pathways in the liver. Robust activation of the NF-κB noncanonical pathway was associated with increased expression of inflammatory markers and acute-phase proteins, and impaired glucose metabolism. Hyperglycemia is detrimental to burn outcome by augmenting inflammation mediated by hepatic noncanonical NF-κB pathway activation.     

Dietary use and conservation concern of edible wetland plants at indo-burma hotspot: a case study from northeast India

Background

The wetlands of the North East India fall among the global hotspots of biodiversity. However, they have received very little attention with relation to their intrinsic values to human kind; therefore their conservation is hardly addressed. These wetlands are critical for the sustenance of the tribal communities.

Methods

Field research was conducted during 2003 to 2006 in seven major wetlands of four districts of Manipur state, Northeast India (viz. Imphal-East, Imphal-West, Thoubal, and Bishnupur). A total of 224 wetland-plant-collectors were interviewed for the use and economics of species using semi-structured questionnaires and interview schedules. Imphal, Bishenpur and Thoubal markets were investigated in detail for influx and consumption pattern of these plants. The collectors were also inquired for medicinal use of wetland species. Nutritive values of 21 species were analyzed in laboratory. The vouchers were collected for all the species and deposited in the CSIR-NEIST (Formerly Regional Research Laboratory), Substation, Lamphelpat, Imphal, Manipur, India.

Results

We recorded 51 edible wetland species used by indigenous people for food and medicinal purposes. Thirty eight species had high medicinal values and used in the traditional system to treat over 22 diseases. At least 27 species were traded in three markets studied (i.e. Imphal, Thoubal and Bishenpur), involving an annual turnover of 113 tons of wetland edible plants and a gross revenue of Rs. 907, 770/- (US$1 = Rs. 45/-). The Imphal market alone supplies 60% of the total business. Eighty per cent of the above mentioned species are very often used by the community. The community has a general opinion that the availability of 45% species has depleted in recent times, 15 species need consideration for conservation while another 7 species deserved immediate protection measures. The nutrient analysis showed that these species contribute to the dietary balance of tribal communities.

Conclusions

Considering the importance of wild wetland plants in local sustenance, it is suggested to protect their habitats, develop domestication protocols of selected species, and build programs for the long-term management of wetland areas by involving local people. Some medicinal plants may also be used to develop into modern medicines.

     

Inflammatory thresholds and the species-specific effects of colonising bacteria in stable chronic obstructive pulmonary disease

Background

There has been increasing interest in the use of newer, culture-independent techniques to study the airway microbiome of COPD patients. We investigated the relationships between the three common potentially pathogenic microorganisms (PPMs) Haemophilus influenzae, Streptococcus pneumoniae and Moraxella catarrhalis, as detected by quantitative PCR (qPCR), and inflammation and health status in stable patients in the London COPD cohort.

Methods

We prospectively collected sputum, serum and plasma samples for analysis of airway bacterial presence and load, and airway and systemic inflammation from 99 stable COPD patients between January 2011 and October 2012. Health status was measured with St George’s Respiratory Questionnaire and COPD Assessment Test.

Results

Airway inflammation and plasma fibrinogen, but not C-reactive protein, were greater in samples with PPM detection (p < 0.001, p = 0.049 and p = 0.261, respectively). Increasing total bacterial load was associated with increasing airway (p < 0.01) but not systemic inflammation (p > 0.05). Samples with high total bacterial loads had significantly higher airway inflammation than both samples without PPM detection and those with lower loads. Haemophilus influenzae presence was associated with significantly higher levels of airway but not systemic inflammation for all given pathogen loads (p < 0.05), and was significantly greater than with other PPMs. No association was observed between inflammation and health status (p > 0.05).

Conclusions

Airway and systemic inflammation, as measured by fibrinogen, is greater in stable COPD patients with PPMs detected using the culture-independent qPCR technique. The airway, but not systemic inflammatory response, appears to have a total pathogen-load threshold and appears attributable to Haemophilus influenzae. However, discordance between inflammation and health status was observed.

Electronic supplementary material

The online version of this article (doi:10.1186/s12931-014-0114-1) contains supplementary material, which is available to authorized users.     

Reversal of the silver inhibition of microorganisms by agar.

Increasing use of silver in the treatment of water has necessitated an examination of microbiological methods for the measurement of silver inactivation of microorganisms. Three common agar media were tested for their ability to neutralize the bacteriostatic effects of silver. Results suggested that growth media differed in their neutralizing capacity; that is, the non-inhibitory media tryptone glucose agar and Trypticase soy agar showed more neutralizing capacity than eosin methylene blue agar. Furthermore, the neutralizing effect appeared to be a function of the soluble component of the media and not of the agar itself.