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91.
The aim of the present investigation is to evaluate adrenomedullary hormones and blood glucose responses to intermale aggression in the bandicoot rat. Aggression elicited a rise in adrenaline and noradrenaline content of the adrenal gland and in blood glucose level in the subordinate rats. No significant change was marked in the dominant rats after aggression. It is suggested that during aggression the subordinate rats suffered from psychosomatic stress that resulted in hyperactivity of the adrenal medulla and consequently hyperglycemia.  相似文献   
92.
Cotyledon explants of Brassica tournefortii L. were excised from germinated seedlings and cultured on Murashige & Skoog's [6] basal medium supplemented with various combinations of cytokinins and auxins, Both cytokinin and auxin were required for induction of shoot organogenesis. Of the three cytokinins tested (in combination with a low concentration of IAA), kinetin was found to be the best for shoot regeneration. On this medium, cotyledonary explants invariably underwent callusing followed by multiple shoot formation. NAA in combination with any of the three cytokinins yielded a reduced number of shoots or none, but favoured good callus growth. Callus so produced also regenerated shoots when subcultured on media containing high concentration of KIN or ZEA and low concentration of IAA. Shoots were rooted during prolonged incubation on the same medium or on MS medium free of growth regulators. Mature plants were grown in the greenhouse.  相似文献   
93.

Rationale

Humans with a dominant negative mutation in STAT3 are susceptible to severe skin infections, suggesting an essential role for STAT3 signaling in defense against cutaneous pathogens.

Methods

To focus on innate antiviral defenses in keratinocytes, we used a standard model of cutaneous infection of severe combined immunodeficient mice with the current smallpox vaccine, ACAM-2000. In parallel, early events post-infection with the smallpox vaccine ACAM-2000 were investigated in cultured keratinocytes of human and mouse origin.

Results

Mice treated topically with a STAT3 inhibitor (Stattic) developed larger vaccinia lesions with higher virus titers and died more rapidly than untreated controls. Cultured human and murine keratinocytes infected with ACAM-2000 underwent rapid necrosis, but when treated with Stattic or with inhibitors of RIP1 kinase or caspase-1, they survived longer, produced higher titers of virus, and showed reduced activation of type I interferon responses and inflammatory cytokines release. Treatment with inhibitors of RIP1 kinase and STAT3, but not caspase-1, also reduced the inflammatory response of keratinocytes to TLR ligands. Vaccinia growth properties in Vero cells, which are known to be defective in some antiviral responses, were unaffected by inhibition of RIP1K, caspase-1, or STAT3.

Conclusions

Our findings indicate that keratinocytes suppress the replication and spread of vaccinia virus by undergoing rapid programmed cell death, in a process requiring STAT3. These data offer a new framework for understanding susceptibility to skin infection in patients with STAT3 mutations. Interventions which promote prompt necroptosis/pyroptosis of infected keratinocytes may reduce risks associated with vaccination with live vaccinia virus.  相似文献   
94.
We describe the characterization of the herpes simplex virus type 2 (HSV-2) gene encoding infected cell protein 32 (ICP32) and virion protein 19c (VP19c). We also demonstrate that the HSV-1 UL38/ORF.553 open reading frame (ORF), which has been shown to specify a viral protein essential for capsid formation (B. Pertuiset, M. Boccara, J. Cebrian, N. Berthelot, S. Chousterman, F. Puvian-Dutilleul, J. Sisman, and P. Sheldrick, J. Virol. 63: 2169-2179, 1989), must encode the cognate HSV type 1 (HSV-1) ICP32/VP19c protein. The region of the HSV-2 genome deduced to contain the gene specifying ICP32/VP19c was isolated and subcloned, and the nucleotide sequence of 2,158 base pairs of HSV-2 DNA mapping immediately upstream of the gene encoding the large subunit of the viral ribonucleotide reductase was determined. This region of the HSV-2 genome contains a large ORF capable of encoding two related 50,538- and 49,472-molecular-weight polypeptides. Direct evidence that this ORF encodes HSV-2 ICP32/VP19c was provided by immunoblotting experiments that utilized antisera directed against synthetic oligopeptides corresponding to internal portions of the predicted polypeptides encoded by the HSV-2 ORF or antisera directed against a TrpE/HSV-2 ORF fusion protein. The type-common immunoreactivity of the two antisera and comparison of the primary amino acid sequences of the predicted products of the HSV-2 ORF and the equivalent genomic region of HSV-1 provided evidence that the HSV-1 UL38 ORF encodes the HSV-1 ICP32/VP19c. Analysis of the expression of the HSV-1 and HSV-2 ICP32/VP19c cognate proteins indicated that there may be differences in their modes of synthesis. Comparison of the predicted structure of the HSV-2 ICP32/VP19c protein with the structures of related proteins encoded by other herpes viruses suggested that the internal capsid architecture of the herpes family of viruses varies substantially.  相似文献   
95.
Two techniques suitable for qualitative radioautographic analysis of histologic sections of human testicular tissue are described. In one, deparaffinized wet slides are coated with photographic emulsion resulting in significant improvement in preservation of histologic quality of the tissue section. In the second procedure stained and processed slides are coated with a thin layer of H.S.R. prior to coating with photographic emulsion. This procedure allows excellent preservation of the stained tissue section and also enables visualization of the reactive cell and its radioautographic image at two different focal planes. The techniques can be applied with equal advantage to histologic preparations of other tissues.  相似文献   
96.
Chowdhury P  Das AM  Goswami P 《Steroids》2005,70(8):494-498
Regioselective synthesis of novel steroidal anti-inflammatory ante drug analogues, viz., [16alpha,17alpha-d]-isoxazolines 1(a-h) and 2(a-h) prepared in a single step in good yield by the reaction of 16-dehydropregnenolone acetate (16-DPA) 1 or related 21-chloro-20-oxopregnane 2 with various aldoximes (a-h) in presence of chloramine-T in refluxing ethanol.  相似文献   
97.
Diel vertical migration is a behavioral antipredator defense that is shaped by a trade-off between higher predation risk in surface waters and reduced growth in deeper waters. The strength of migration of zooplankton increases with a rise in the abundance of predators and their exudates (kairomone). Recent studies span multiple trophic levels, which lead to the concept of coupled vertical migration. The migrations that occur at one trophic level can affect the vertical migration of the next lower trophic level, and so on, throughout the food chain. This is called cascading migration. In this paper, we introduce cascading migration in a well-known model (Hastings and Powell, Ecology 73:896–903, 1991). We represent the dynamics of the system as proposed by Hastings and Powell as a phytoplankton–zooplankton–fish (prey–middle predator–top predator) model where fish affect the migrations of zooplankton, which in turn affect the migrations of motile phytoplankton. The system under cascading migration enhances system stability and population coexistence. It is also observed that for a higher rate of cascading migration, the system shows chaotic behavior. We conclude that the observations of Hastings and Powell remain true if the cascading migration rate is high enough.  相似文献   
98.
Calcium signaling is a key regulator of processes important in differentiation. In colon cancer cells differentiation is associated with altered expression of specific isoforms of calcium pumps of the endoplasmic reticulum and the plasma membrane, suggesting that differentiation of colon cancer cells is associated with a major remodeling of calcium homeostasis. Purinergic and neurotensin receptor activation are known regulators of cytosolic free Ca2+ levels in colon cancer cells. This study aimed to assess changes in cytosolic free Ca2+ levels in response to ATP and neurotensin with differentiation induced by sodium butyrate or culturing post-confluence. Parameters assessed included peak cytosolic free Ca2+ level after activation; time to reach peak cytosolic free Ca2+ and the EC50 of dose response curves. Our results demonstrate that differentiation of HT-29 colon cancer cells is associated with a remodeling of both ATP and neurotensin mediated Ca2+ signaling. Neurotensin-mediated calcium signaling appeared more sensitive to differentiation than ATP-mediated Ca2+ signaling.  相似文献   
99.
The functions of proteins are often realized through their mutual interactions. Determining a relative transformation for a pair of proteins and their conformations which form a stable complex, reproducible in nature, is known as docking. It is an important step in drug design, structure determination, and understanding function and structure relationships. In this paper, we extend our nonuniform fast Fourier transform-based docking algorithm to include an adaptive search phase (both translational and rotational) and thereby speed up its execution. We have also implemented a multithreaded version of the adaptive docking algorithm for even faster execution on multicore machines. We call this protein-protein docking code F2Dock (F2 = Fast Fourier). We have calibrated F2Dock based on an extensive experimental study on a list of benchmark complexes and conclude that F2Dock works very well in practice. Though all docking results reported in this paper use shape complementarity and Coulombic-potential-based scores only, F2Dock is structured to incorporate Lennard-Jones potential and reranking docking solutions based on desolvation energy .  相似文献   
100.
In enteroaggregative hemorrhagic Escherichia coli (EAHEC) O104 the complex antibiotic resistance gene loci (CRL) found in the region of divergence 1 (RD1) within E. coli genomic island 3 (GI3) contains blaTEM-1, strAB, sul2, tet(A)A, and dfrA7 genes encoding resistance to ampicillin, streptomycin, sulfamethoxazole, tetracycline and trimethoprim respectively. The precise arrangement of antibiotic resistance genes and the role of mobile elements that drove the evolutionary events and created the CRL have not been investigated. We used a combination of bioinformatics and iterative BLASTn searches to determine the micro-evolutionary events that likely led to the formation of the CRL in GI3 using the closed genome sequences of EAHEC O104:H4 strains 2011C-3493 and 2009EL-2050 and high quality draft genomes of EAHEC E. coli O104:H4 isolates from sporadic cases not associated with the initial outbreak. Our analyses indicate that the CRL in GI3 evolved from a progenitor structure that contained an In2-derived class 1 integron in a Tn21/Tn1721 hybrid backbone. Within the hybrid backbone, a Tn6029-family transposon, identified here as Tn6029C abuts the sul1 gene in the 3´-Conserved Segment (-CS) of a class 1 integron generating a unique molecular signature that has only previously been observed in pASL01a, a small plasmid found in commensal E. coli in West Africa. From this common progenitor, independent IS26-mediated events created two novel transposons identified here as Tn6029D and Tn6222 in 2011C-3493 and 2009EL-2050 respectively. Analysis of RD1 within GI3 reveals IS26 has played a crucial role in the assembly of regions within the CRL.  相似文献   
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