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Animals bearing malignant grafts reject normal grafts that express through gene transfer the same antigen.
Breaking the state of immunological unresponsiveness of tumor-bearing individuals to cancer is a prerequisite for active or passive tumor-specific immunotherapy. To study this problem the immunogenic MHC class I antigen, K216 was transfected into a progressor tumor. The transfected tumors were regularly rejected by normal mice but grew progressively in mice bearing nontransfected tumors. In addition, transgenic mice were derived to obtain normal cells and tissues expressing the same K216 gene product. Normal mice rejected K216-positive normal or malignant tissue grafts and generated K216-specific CTL in vitro and in vivo in response to these challenges. In contrast, mice bearing nontransfected tumors, though rejecting K216-positive nonmalignant tissue grafts, did not reject K216-positive tumors nor generate K216-specific CTL in response to K216-positive tumor cells. Mice bearing K216-positive tumors also rejected the nonmalignant K216-positive tissue grafts, but this in vivo response failed to lead to rejection of the simultaneously present tumor graft expressing the same antigen; in fact, immunity had no measurable effect whatsoever on tumor size or incidence and caused no selection for antigen loss variants. Taken together, the present findings suggest that transfer of expression of a target antigen into nonmalignant cells provides a way for obtaining effective stimulation of antigen-specific CTL in tumor-bearing mice, but that additional manipulations will be required to cause immunological rejection of established tumors
Severe malaria - a case of fatal Plasmodium knowlesi infection with post-mortem findings: a case report.
BACKGROUND: Zoonotic malaria caused by Plasmodium knowlesi is an important, but newly recognized, human pathogen. For the first time, post-mortem findings from a fatal case of knowlesi malaria are reported here.
CASE PRESENTATION: A formerly healthy 40 year-old male became symptomatic 10 days after spending time in the jungle of North Borneo. Four days later, he presented to hospital in a state of collapse and died within two hours. He was hyponatraemic and had elevated blood urea, potassium, lactate dehydrogenase and amino transferase values; he was also thrombocytopenic and eosinophilic. Dengue haemorrhagic shock was suspected and a post-mortem examination performed. Investigations for dengue virus were negative. Blood for malaria parasites indicated hyperparasitaemia and single species P. knowlesi infection was confirmed by nested-PCR. Macroscopic pathology of the brain and endocardium showed multiple petechial haemorrhages, the liver and spleen were enlarged and lungs had features consistent with ARDS. Microscopic pathology showed sequestration of pigmented parasitized red blood cells in the vessels of the cerebrum, cerebellum, heart and kidney without evidence of chronic inflammatory reaction in the brain or any other organ examined. Brain sections were negative for intracellular adhesion molecule-1. The spleen and liver had abundant pigment containing macrophages and parasitized red blood cells. The kidney had evidence of acute tubular necrosis and endothelial cells in heart sections were prominent.
CONCLUSIONS: The overall picture in this case was one of systemic malaria infection that fit the WHO classification for severe malaria. Post-mortem findings in this case were unexpectedly similar to those that define fatal falciparum malaria, including cerebral pathology. There were important differences including the absence of coma despite petechial haemorrhages and parasite sequestration in the brain. These results suggest that further study of knowlesi malaria will aid the interpretation of, often conflicting, information on malaria pathophysiology in humans
Two Warehouse Inventory Model for Deteriorating Products with Stock Dependent Demand and Shortages
In this paper a deterministic inventory model for two warehouses has been developed. In two warehouses the first is the owned warehouse with a fixed capacity of W units and the other one is rented warehouse with unlimited stocking capacity. The deterioration occurs in both the warehouses. First the demand is fulfilled from the inventory in rented warehouse and after thatthe inventory in owned warehouse has been used. The shortages are allowed in owned warehouse only and the excess demand is partially backlogged. For the generality of the model we presented the equations for total cost of the system. A numerical example and sensitivity analysis with respect to different associated parameters has also been presented to illustrate the model
A study of KIT activating mutations in acute myeloid leukemia M0 subtype in north India
Acute Myeloid Leukemia (AML)-M0 is a cancer of blood-forming cells in the bone marrow. KIT gene is a receptor tyrosine kinase class III that is expressed on by early hematopoietic progenitor cells and plays an important role in hematopoietic stem cell proliferation, differentiation and survival. Mutations of KIT receptor tyrosine kinase are involved in the constitutive activation and development of human hematologic malignancies. We have designed this study aiming to identify and determine the frequency and prevalence of mutations in North Indian patients suffering from AML-M0. To perceive the KIT gene mutations, we have carried out PCR–SSCP followed by direct DNA sequencing in 50 AML-M0 cases. We have found eight cases (24.2%) with t(8;21) having 12 point mutations whereas three cases (17.6%) with inv(16) having four point mutations. The point mutation detected at exon 9 in five cases is Asp496Val. Eight different point mutations were identified at exon 11 in seven AML-M0 cases that include Lys550Asn, Tyr568Ser, Ile571Leu, Tyr578Pro, Trp582Ser and Arg588Met. Point mutations at codons Ile571Leu and Trp582Ser was found in two independent cases. Three point mutations were found in exon 17 (Leu813Pro, Lys818Arg, Val825Ala) in three AML-M0 cases. The results underline that the KIT gene appears to be most frequently mutated target in AML-M0 cases. These observations suggest that mutations in exon 11 of the KIT gene might be useful molecular genetic markers in AML-M0 and these mutations might be related to progression and clinical pathogenesis.Keywords: PCR; SSCP–PAGE; KIT; Malignant; AML-M0; Mutation
Sexual conflict over remating interval is modulated by the sex peptide pathway
Sexual conflict, in which the evolutionary interests of males and females diverge, shapes the evolution of reproductive systems across diverse taxa. Here we used the fruit fly to study sexual conflict in natural, three-way interactions comprising a female, her current and previous mates. We manipulated the potential for sexual conflict by using sex peptide receptor (SPR) null females and by varying remating from 3 to 48h, a period during which natural rematings frequently occur. SPR-lacking females do not respond to sex peptide transferred during mating and maintain virgin levels of high receptivity and low fecundity. In the absence of SPR there was a convergence of fitness interests, with all individuals gaining highest productivity at 5h remating. This suggests that the expression of sexual conflict was reduced. We observed an unexpected second male-specific advantage to early remating, resulting from an increase in the efficiency of second male sperm use. This early window of opportunity for exploitation by second males depended on the presence of SPR. The results suggest that the sex peptide pathway can modulate the expression of sexual conflict in this system, and show how variation in the selective forces that shape conflict and co-operation can be maintained
Effects of fluoroquinolones and tetracyclines on mitochondria of human retinal MIO-M1 cells
Our goal was to explore the detrimental impacts of ciprofloxacin (CPFX) and tetracycline (TETRA) on human retinal Müller (MIO-M1) cells in vitro. Cells were exposed to 30, 60 and 120 μg/ml of CPFX and TETRA. The cellular metabolism was measured with the MTT assay. The JC-1 and CM-H2DCFDA assays were used to evaluate the levels of mitochondrial membrane potential (MMP) and ROS (reactive oxygen species), respectively. Mitochondrial DNA (mtDNA) copy number, along with gene expression levels associated with apoptotic (BAX, BCL2-L13, BCL2, CASP-3 and CASP-9), inflammatory (IL-6, IL-1β, TGF-α, TGF-β1 and TGF-β2) and antioxidant pathways (SOD2, SOD3, GPX3 and NOX4) were analyzed via Quantitative Real-Time PCR (qRT-PCR). Bioenergetic profiles were measured using the Seahorse® XF Flux Analyzer. Cells exposed 24 h to 120 μg/ml TETRA demonstrated higher cellular metabolism compared to vehicle-treated cells. At each time points, (i) all TETRA concentrations reduced MMP levels and (ii) ROS levels were reduced by TETRA 120 μg/ml treatment. TETRA caused (i) higher expression of CASP-3, CASP-9, TGF-α, IL-1B, GPX3 and SOD3 but (ii) decreased levels of TGF-B2 and SOD2. ATP production and spare respiratory capacity declined with TETRA treatment. Cellular metabolism was reduced with CPFX 120 μg/ml in all cultures and 60 μg/ml after 72 h. The CPFX 120 μg/ml reduced MMP in all cultures and ROS levels (72 h). CPFX treatment (i) increased expression of CASP-3, CASP-9, and BCL2-L13, (ii) elevated the basal oxygen consumption rate, and (iii) lowered the mtDNA copy numbers and expression levels of TGF-B2, IL-6 and IL-1B compared to vehicle-control cells. We conclude that clinically relevant dosages of bactericidal and bacteriostatic antibiotics can have negative effects on the cellular metabolism and mitochondrial membrane potential of the retinal MIO-M1 cells in vitro. It is noteworthy to mention that apoptotic and inflammatory pathways in exposed cells were affected significantly This is the first study showing the negative impact of fluoroquinolones and tetracyclines on mitochondrial behavior of human retinal MIO-M1 cells
Importance of the Collagen Adhesin Ace in Pathogenesis and Protection against Enterococcus faecalis Experimental Endocarditis
Ace is an adhesin to collagen from Enterococcus faecalis expressed conditionally after growth in serum or in the presence of collagen. Here, we generated an ace deletion mutant and showed that it was significantly attenuated versus wild-type OG1RF in a mixed infection rat endocarditis model (P<0.0001), while no differences were observed in a peritonitis model. Complemented OG1RFΔace (pAT392::ace) enhanced early (4 h) heart valve colonization versus OG1RFΔace (pAT392) (P = 0.0418), suggesting that Ace expression is important for early attachment. By flow cytometry using specific anti-recombinant Ace (rAce) immunoglobulins (Igs), we showed in vivo expression of Ace by OG1RF cells obtained directly from infected vegetations, consistent with our previous finding of anti-Ace antibodies in E. faecalis endocarditis patient sera. Finally, rats actively immunized against rAce were less susceptible to infection by OG1RF than non-immunized (P = 0.0004) or sham-immunized (P = 0.0475) by CFU counts. Similarly, animals given specific anti-rAce Igs were less likely to develop E. faecalis endocarditis (P = 0.0001) and showed fewer CFU in vegetations (P = 0.0146). In conclusion, we have shown for the first time that Ace is involved in pathogenesis of, and is useful for protection against, E. faecalis experimental endocarditis
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