Fibroblast dynamics as an in vitro screening platform for anti‐fibrotic drugs in primary myelofibrosis

Although the cause for bone marrow fibrosis in patients with myelofibrosis remains controversial, it has been hypothesized that it is caused by extensive fibroblast proliferation under the influence of cytokines generated by the malignant megakaryocytes. Moreover, there is no known drug therapy which could reverse the process. We studied the fibroblasts in a novel system using the hanging drop method, evaluated whether the fibroblasts obtain from patients are part of the malignant clone of not and, using this system, we screen a large library of FDA‐approved drugs to identify potential drugs candidates that might be useful in the treatment of this disease, specifically which would inhibit fibroblast proliferation and the development of bone marrow fibrosis. We have found that the BM fibroblasts are not part of the malignant clone, as previously suspected and two immunosuppressive medications—cyclosporine and mycophenolate mophetil, as most potent suppressors of the fibroblast collagen production thus potentially inhibitors of bone marrow fibrosis production in myelofibrosis.     

Lung tissue extracellular matrix-derived hydrogels protect against radiation-induced lung injury by suppressing epithelial–mesenchymal transition

This study aimed to examine whether lung tissue extracellular matrix (ECM) hydrogels have protective effects on radiation-induced lung injury (RILI). The cytocompatibility and histocompatibility were tested for the obtained ECM-derived hydrogel. Sprague–Dawley rats were randomly divided into three groups (n = 18): control group (control); rats receiving irradiation and intratracheal injection of normal saline (IR + NS); and rats receiving irradiation and intratracheal injection of lung ECM-derived hydrogel (IR + ECM). The wet/dry weight ratio was used to evaluate the congestion and edema of the lungs. Histopathological analysis of lung tissues was performed using hemotoxylin and eosin staining and Masson's trichrome staining. Immunohistochemical staining and western blot analyses were carried out to determine the expression of epithelial–mesenchymal transition (EMT)-related proteins in lung tissues (E-cadherin, α-smooth muscle actin [α-SMA], and vimentin). In addition, tumor necrosis factor-α (TNF-α), transforming growth factor-β1 (TGF-β1) and interleukin-6 (IL-6), hydroxyproline, malondialdehyde (MDA), and superoxide dismutase (SOD) levels were also evaluated. The ECM-derived hydrogels had good cytocompatibility and histocompatibility. ECM-derived hydrogel treatment improved lung histopathology injury and pulmonary edema. Higher expression of E-cadherin and lower expression of vimentin and α-SMA were found in the IR + ECM group compared with those in the IR + NS group. Hydroxyproline levels were reduced by ECM-derived hydrogel treatment compared with those in the IR + NS group. Obvious increases of TNF-α, IL-6, and TGF-β1 were identified following irradiation. Marked reductions in MDA content and increases in SOD were induced by ECM-derived hydrogel treatment in rats after radiation. ECM-derived hydrogels were shown to protect against RILI, potentially by reducing EMT, inflammation, and oxidative damage.     

Oxygen and nitrate-dependent regulation of <Emphasis Type="Italic">dmsABC</Emphasis> operon expression in <Emphasis Type="Italic">Escherichia coli</Emphasis>: sites for Fnr and NarL protein interactions

Background  

Escherichia coli can respire anaerobically using dimethyl sulfoxide (DMSO) or trimethylamine-N-oxide (TMAO) as the terminal electron acceptor for anaerobic energy generation. Expression of the dmsABC genes that encode the membrane-associated DMSO/TMAO reductase is positively regulated during anaerobic conditions by the Fnr protein and negatively regulated by the NarL protein when nitrate is present.     

Meeting the meiotic challenge: Specializations in mammalian oocyte spindle formation

Oocytes uniquely accumulate cytoplasmic constituents to support early embryogenesis. This unique specialization is accompanied by acquisition of a large size and by execution of asymmetric meiotic divisions that preserve precious ooplasm through the expulsion of minimal size polar bodies. While often taken for granted, these basic features of oogenesis necessitate unique specializations of the meiotic apparatus. These include a chromatin‐sourced RanGTP gradient that restricts spindle size by defining a spatial domain where meiotic spindles form, acentriolar centrosomes that rely on microtubule organizing centers to form spindle poles, and an actin‐based mechanism for asymmetric spindle positioning. Additionally, localized protein synthesis to support spindle formation is achieved in the spindle forming region, whilst protein synthesis is reduced elsewhere in the ooplasm. This is achieved through enrichment of spindle‐related mRNAs in the spindle forming region combined with local PLK1‐mediated phosphorylation and inactivation of the translational repressor EIF4EBP1. This allows PLK1 to function as an important regulatory nexus through which endogenous and exogenous signals can impact spindle formation and function, and highlights the important role that PLK1 may have in maintaining oocyte quality and fertility.     

Minimizing the impact of the mosquito adulticide naled on honey bees, Apis mellifera (Hymenoptera: Apidae): aerial ultra-low-volume application using a high-pressure nozzle system

The impact of the mosquito adulticide naled on honey bees, Apis mellifera L., was evaluated by exposing test beehives to nighttime aerial ultra-low-volume (ULV) applications using a high-pressure nozzle system. The tests were conducted during routine mosquito control missions at Manatee County, Florida, in summer 2000. Two treatment sites were sprayed a total of four times over a 10-wk period. Honey bees, which clustered outside of the hive entrances, were subjected to naled exposure during these mosquito control sprays. The highest average naled ground deposition was 2,688 microg/m2 at the Port Manatee site, which resulted in statistically significant bee mortality (118) compared with the controls. At the Terra Ceia Road site, an intermediate level of naled deposition was found (1,435 microg/m2). For this spray mission, the range of dead bees per hive at Terra Ceia was 2 to 9 before spraying and 5 to 36 after naled application. Means of all other naled ground depositions were < 850 microl/m2. We concluded that substantial bee mortality (> 100 dead bees) resulted when naled residue levels were > 2,000 kg/m2 and honey bees were clustered outside of the hive entrances during mosquito adulticide applications. Compared with the flat-fan nozzle systems currently used by most of Florida's mosquito control programs, the high-pressure nozzle system used in this experiment substantially reduced environmental insecticide contamination and lead to decreased bee mortality. Statistical analysis also showed that average honey yield at the end of the season was not significantly reduced for those hives that were exposed to the insecticide.     

Risk factors for human disease emergence

A comprehensive literature review identifies 1415 species of infectious organism known to be pathogenic to humans, including 217 viruses and prions, 538 bacteria and rickettsia, 307 fungi, 66 protozoa and 287 helminths. Out of these, 868 (61%) are zoonotic, that is, they can be transmitted between humans and animals, and 175 pathogenic species are associated with diseases considered to be 'emerging'. We test the hypothesis that zoonotic pathogens are more likely to be associated with emerging diseases than non-emerging ones. Out of the emerging pathogens, 132 (75%) are zoonotic, and overall, zoonotic pathogens are twice as likely to be associated with emerging diseases than non-zoonotic pathogens. However, the result varies among taxa, with protozoa and viruses particularly likely to emerge, and helminths particularly unlikely to do so, irrespective of their zoonotic status. No association between transmission route and emergence was found. This study represents the first quantitative analysis identifying risk factors for human disease emergence.     

Intensified Tuberculosis Case Finding among Malnourished Children in Nutritional Rehabilitation Centres of Karnataka,India: Missed Opportunities

Background

Severe acute malnutrition (SAM) is the most serious form of malnutrition affecting children under-five and is associated with many infectious diseases including Tuberculosis (TB). In India, nutritional rehabilitation centres (NRCs) have been recently established for the management of SAM including TB. The National TB Programme (NTP) in India has introduced a revised algorithm for diagnosing paediatric TB. We aimed to examine whether NRCs adhered to these guidelines in diagnosing TB among SAM children.

Methods

A cross-sectional study involving review of records of all SAM children identified by health workers during 2012 in six tehsils (sub-districts) with NRCs (population: 1.8 million) of Karnataka, India.

Results

Of 1927 identified SAM children, 1632 (85%) reached NRCs. Of them, 1173 (72%) were evaluated for TB and 19(2%) were diagnosed as TB. Of 1173, diagnostic algorithm was followed in 460 (37%). Among remaining 763 not evaluated as per algorithm, tuberculin skin test alone was conducted in 307 (41%), chest radiography alone in 99 (13%) and no investigations in 337 (45%). The yield of TB was higher among children evaluated as per algorithm (4%) as compared to those who were not (0.3%) (OR: 15.3 [95%CI: 3.5-66.3]). Several operational challenges including non-availability of a full-time paediatrician, non-functioning X-ray machine due to frequent power cuts, use of tuberculin with suboptimal strength and difficulties in adhering to a complex diagnostic algorithm were observed.

Conclusion

This study showed that TB screening in NRCs was sub-optimal in Karnataka. Some children did not reach the NRC, while many of those who did were either not or sub-optimally evaluated for TB. This study pointed to a number of operational issues that need to be addressed if this collaborative strategy is to identify more TB cases amongst malnourished children in India.