Acid-functionalized single-walled carbon nanotubes alter epithelial tight junctions and enhance paracellular permeability

The T(EB4)Nta, T(IBj5)Nta, and T(B362i)NtA strains were constructed by introgressing the insertionaltranslocations EB4, IBj5, and B362i from Neurospora crassa into the related species N. tetrasperma. Theprogeny from crosses of T(IBj5)Nta and T(B362i)NtA with opposite mating-type derivatives of the standard N.tetrasperma strain 85 exhibited a unique and unprecedented transmission ratio distortion (TRD) that disfavoredhomokaryons produced following alternate segregation relative to those produced following adjacent-1 segregation. The TRD was not evident among the [mat A ? mat a] dikaryons produced following either segregation. Further, crosses of the T(IBj5)Nta and T(B362i)NtA strains with the Eight spore (E) mutant showed anunusual ascus phenotype called ‘max-4’. We propose that the TRD and the max-4 phenotype are manifestations of the same Bateson-Dobzhansky-Muller incompatibility (BDMI). Since the TRD selects against 2/3 ofthe homokaryotic progeny from each introgression cross, the BDMI would have enriched for the dikaryoticprogeny in the viable ascospores, and thus, paradoxically, facilitated the introgressions.

Audit of caesarian deliveries in a tertiary care center, in rural Bangalore, India

Background: The Robson’s Ten-Group Classification System allows critical analysis of caesarean deliveries according to characteristics of pregnancy. The objective was to analyze caesarean section rates in a rural tertiary care teaching hospital in Bangalore, using Robson’s ten groups classification.Methods: This study was done in MVJ Medical College and Research Hospital, a rural tertiary care teaching hospital. All patients who underwent caesarean delivery, between November 2017 and October 2018, were included in the study. Women were classified in 10 groups according to Robson’s classification. For each group, authors calculated its relative contribution to the overall caesarean rate.Results: The overall caesarean section rate was 46.7%. The main contributors to this high caesarean rate were primiparous women in spontaneous labour (group 1) and women with previous caesarean section (group 5).  52.1% of CS were conducted on women who were unbooked or booked at a peripheral health facility and referred to present institution due to complications in labor. Strategies to lower CS rates would include encouraging women with previous CS, to undergo trial of labor to reduce CS rates for group 5C. Sensitization of staff in peripheral medical facilities for early referral of high-risk pregnancies to a tertiary care center for better control of medical complications like hypertensive disorders of diabetes mellitus. Other strategies include offering external cephalic version to eligible women with breech presentation and consider offering vaginal breech delivery to suitable women in groups 6 and 7.Conclusions: The Robson’s classification is easy to use. It is time to implement obstetric audit to lower the overall CS rates.

Age-dependent increase in green autofluorescence of blood erythrocytes.

Green auto-fluorescence (GAF) of different age groups of mouse blood erythrocytes was determined by using a double in vivo biotinylation (DIB) technique that enables delineation of circulating erythrocytes of different age groups. A significant increase in GAF was seen for erythrocytes of old age group (age in circulation more than 40 days) as compared to young erythrocytes (age less than 15 days). Erythrocytes are removed from blood circulation by macrophages in the reticulo-endothelial system and depletion of macrophages results in an increased proportion of aged erythrocytes in the blood. When mice were depleted of macrophages for 7 days by administration of clodronate loaded liposomes, the overall GAF of erythrocytes increased significantly and this increase could be ascribed to an increase in GAF of the oldest population of erythrocytes. Using the DIB technique, the GAF of a cohort of blood erythrocyte generated during a 5 day window was tracked in vivo. GAF of the defined cohort of erythrocytes remained low till 40 days of age in circulation and then increased steeply till the end of the life span of erythrocytes. Taken together our results provide evidence for an age dependent increase in the GAF of blood erythrocytes that is accentuated by depletion of macrophages. Kinetics of changes in GAF of circulating erythrocytes with age has also been defined.

Evidence for lipopolysaccharide-induced differentiation of RAW264.7 murine macrophage cell line into dendritic like cells.

Effect of lipopolysaccharide (LPS) on RAW264.7 macrophage cell line was studied. LPS-treated RAW264.7 cells increased in cell size and acquired distinct dendritic morphology. At the optimal dose of LPS (1 mg/ml), almost 70% RAW264.7 cells acquired dendritic morphology. Flow cytometric studies indicate that the cell surface markers known to be expressed on dendritic cells and involved in antigen presentation and T cell activation (B 7.1, B 7.2, CD40, MHC class II antigens and CD1d) were also markedly upregulated on LPS-treated RAW 264.7 cells. Our results suggest the possibility that LPS by itself could constitute a sufficient signal for differentiation of macrophages into DC-like cells.

Murine model of BCG lung infection: dynamics of lymphocyte subpopulations in lung interstitium and tracheal lymph nodes.

C57Bl/6 female mice were infected with an intrapulmonary dose of 2.5 x 10(4) BCG (Mycobacterium bovis Bacillus Calmette-Guerin). Lymphocyte populations in lung interstitium and lung-associated tracheal lymph nodes (LN) were examined at 1, 2, 4, 5, 6, 8 and 12 weeks after infection. BCG load in lungs peaked between 4-6 weeks post-infection and declined to very low levels by the 12th week of infection. Lung leukocytes were obtained over the course of infection by enzyme digestion of lung tissue followed by centrifugation over Percoll discontinuous density gradients. By 4 to 6 weeks after infection, numbers of lung leukocytes had more than doubled but the proportions of lymphocytes (about 70%), macrophages (about 18%) and granulocytes (about 12%) remained essentially unaltered. Flow cytometric studies indicated: (i) the total number of CD3+ T cells in lungs increased by 3-fold relative to uninfected controls at 5 to 6 weeks post-infection, but the relative proportions of CD4 and CD8 cells within the T cell compartment remained unaltered; (ii) relative proportion of NK cells in lungs declined by 30% but the total number of NK cells (NK1.1+) per lung increased by about 50%, 5-6 weeks post infection; (iii) tracheal LN underwent marked increase in size and cell recoveries (6-10-fold increase) beginning 4 weeks after infection. While both T and B cells contributed to the increase in cell recoveries from infected tracheal LNs, the T/B ratio declined significantly but CD4/CD8 ratio remained unaltered. In control mice, IFNgamma producing non-T cells outnumbered T cells producing IFNgamma. However, as the adaptive response to infection evolves, marked increase occur in the number of IFNgamma producing T cells, but not NK cells in the lungs. Thus, T cells are the primary cell type responsible for the adaptive IFNgamma response to pulmonary BCG infection. Few T cells in tracheal LN of BCG infected mice produce IFNgamma, suggesting that maturational changes associated with migration to the lungs or residence in the lungs enhance the capability of some T cells to produce this cytokine.

Identification and partial purification of a human natural killer cell proliferation-inducing factor.

Culture supernatants of Concanavalin A activated human peripheral blood mononuclear cells were found to contain a factor which induced proliferative response in normal peripheral blood mononuclear cells. This proliferation-inducing factor specifically induced and sustained proliferation of purified human NK cells but not of T or B cells. Although interleukin 2 (IL12) also has proliferation-inducing effects on NK cells, the partially purified proliferationinducing factor preparations contained no measurable IL2 contamination. Moreover, neutralizing anti-IL2 antibodies did not block the growth effect of proliferation-inducing factor on purified human NK cells. Other cytokines which were tested, including IL4, IL6, IL7, IL12, TNF and IFN, were all found to be inactive in the proliferation-inducing factor assay. While proliferation-inducing factor by itself had no effect on T-cell proliferation, IL2-induced proliferation of T cells was significantly enhanced in the presence of proliferation-inducing factor, as was IL2-induced NK-cell proliferation. NK cells could be maintained in culture for at least a month in the presence of proliferation-inducing factor alone, but the cells lost their cytolytic activity after 3-4 weeks in culture. Addition of IL2, to NK cells which had been cultured in the presence of proliferation-inducing factor, restored their cytotoxicity. Proliferation-inducing factor activity was partially purified on an anion exchange HPLC column. The molecular weight of proliferation- inducing factor appeared to be about 10 kDa, based on its elution profile on a sizing HPLC column. Our results indicate that proliferation-inducing factor is a novel NK-cell proliferationinducing factor.