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1.
Artificial diets were reviewed and two tested. The highest level of survival to the adult stage (72%) was obtained on a modified diet of Odell & Rollinson (1966). Rearing required 61 days for males and 70 days for females. Wing deformation occurred in 16% of the adults. The sex ratio ( : ) was 0.80. Average pupal weight was 281 mg for males and 368 mg for females. Females averaged 102 eggs (range 80–125 eggs). Neonates from field-collected egg masses started hatching on 6 December; frost was not necessary for hatching. Hatching could be postponed until at least 10 November of the following year by storing egg masses at-2°C. L. monacha can be maintained continuously in the laboratory.
Zusammenfassung Eine Massenvermehrung der Nonne, Lymantria monacha (L.), trat in 1984 auf 500 ha Pinus sylvestris bei Budelerbergen (S.O. der Niederlande) auf und betraf 1985 eine Fläche von 2800 ha. Obwohl die Vermehrung durch eine Luftapplikation mit Dimilin 25 bekämpft werden konnte, wurden Untersuchungen begonnen zur Entwicklung von für die Umwelt sicheren Bekämpfungsmethoden, besonders die Anwendung von Virosen. Das Ziel bestand in der Virusproduktion in künstlichen Raupenzuchten. Die Nonne wurde bisher mit verschiedenen für andere Insektenarten oder speziell für diesen Zweck entwickelten künstlichen Nährböden gezüchtet. Da die Zusammensetzung dieser Nährböden und die Zuchtmethoden nicht veröffentlicht waren und da wenige Details über die Raupenentwicklung vorlagen, wurden modifizierten Nährböden von McMorran sowie von Odell & Rollinson für die Massenzucht der Nonne geprüft.
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Current status of antisense DNA methods in behavioral studies   总被引:4,自引:0,他引:4  
Ogawa  S; Pfaff  DW 《Chemical senses》1998,23(2):249-255
The antisense DNA method has been used successfully to block the expression of specific genes in vivo in neuronal systems. An increasing number of studies in the last few years have shown that antisense DNA administered directly into the brain can modify various kinds of behaviors. These findings strongly suggest that the antisense DNA method can be used as a powerful tool to study causal relationships between molecular processes in the brain and behavior. In this article we review the current status of the antisense method in behavioral studies and discuss its potentials and problems by focusing on the following four aspects; (i) optimal application paradigms of antisense DNA methods in behavioral studies; (ii) efficiencies of different administration methods of antisense DNA used in behavioral studies; (iii) determination of specificity of behavioral effects of antisense DNA; and (iv) discrepancies between antisense DNA effects on behaviors and those on protein levels of the targeted gene.   相似文献   
4.

Background

A new subgroup of HIV-1, designated Group P, was recently detected in two unrelated patients of Cameroonian origin. HIV-1 Group P phylogenetically clusters with SIVgor suggesting that it is the result of a cross-species transmission from gorillas. Until today, HIV-1 Group P has only been detected in two patients, and its degree of adaptation to the human host is largely unknown. Previous data have shown that pandemic HIV-1 Group M, but not non-pandemic Group O or rare Group N viruses, efficiently antagonize the human orthologue of the restriction factor tetherin (BST-2, HM1.24, CD317) suggesting that primate lentiviruses may have to gain anti-tetherin activity for efficient spread in the human population. Thus far, three SIV/HIV gene products (vpu, nef and env) are known to have the potential to counteract primate tetherin proteins, often in a species-specific manner. Here, we examined how long Group P may have been circulating in humans and determined its capability to antagonize human tetherin as an indicator of adaptation to humans.

Results

Our data suggest that HIV-1 Group P entered the human population between 1845 and 1989. Vpu, Env and Nef proteins from both Group P viruses failed to counteract human or gorilla tetherin to promote efficient release of HIV-1 virions, although both Group P Nef proteins moderately downmodulated gorilla tetherin from the cell surface. Notably, Vpu, Env and Nef alleles from the two HIV-1 P strains were all able to reduce CD4 cell surface expression.

Conclusions

Our analyses of the two reported HIV-1 Group P viruses suggest that zoonosis occurred in the last 170 years and further support that pandemic HIV-1 Group M strains are better adapted to humans than non-pandemic or rare Group O, N and P viruses. The inability to antagonize human tetherin may potentially explain the limited spread of HIV-1 Group P in the human population.  相似文献   
5.
Photo-crosslinkable, fumaric acid monoethyl ester-functionalized triblock oligomers are synthesized and copolymerized with N-vinyl-2-pyrrolidone to form biodegradable photo-crosslinked hydrogels. Poly(ethylene glycol) is used as the middle hydrophilic segment and the hydrophobic segments are based on D,L-lactide, trimethylene carbonate or a mixture of these monomers. Two model proteins, lysozyme and albumin, are incorporated in the hydrogels and their release is studied. The composition of the hydrophobic segments could be used to tune degradation behavior and release rates. Careful optimization of photo-polymerization conditions is needed to limit conjugation of proteins to the hydrogels and protein denaturation.  相似文献   
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L-Lactate dehydrogenase (L-LDH, E.C. 1.1.1.27) is encoded by two or three loci in all vertebrates examined, with the exception of lampreys, which have a single LDH locus. Biochemical characterizations of LDH proteins have suggested that a gene duplication early in vertebrate evolution gave rise to Ldh-A and Ldh-B and that an additional locus, Ldh-C arose in a number of lineages more recently. Although some phylogenetic studies of LDH protein sequences have supported this pattern of gene duplication, others have contradicted it. In particular, a number of studies have suggested that Ldh-C represents the earliest divergence among vertebrate LDHs and that it may have diverged from the other loci well before the origin of vertebrates. Such hypotheses make explicit statements about the relationship of vertebrate and invertebrate LDHs, but to date, no closely related invertebrate LDH sequences have been available for comparison. We have attempted to provide further data on the timing of gene duplications leading to multiple vertebrate LDHs by determining the cDNA sequence of the LDH of the tunicate Styela plicata. Phylogenetic analyses of this and other LDH sequences provide strong support for the duplications giving rise to multiple vertebrate LDHs having occurred after vertebrates diverged from tunicates. The timing of these LDH duplications is consistent with data from a number of other gene families suggesting widespread gene duplication near the origin of vertebrates. With respect to the relationships among vertebrate LDHs, our data are not consistent with previous claims that Ldh-C represented the earliest divergence. However, the precise relationships among some of the main lineages of vertebrate LDHs were not resolved in our analyses.   相似文献   
8.

Background

The past ten years have witnessed a rising trend in the prevalence and duration of breastfeeding in Italy, but breastfeeding rates increase in an unequal way; they are higher in the North of Italy than in the South. The purpose of this study was to describe the experiences, expectations and beliefs of a sample of mothers, and to identify differences, if any, between the North and the South of Italy.

Methods

The study was conducted in two regions of Italy, Friuli Venezia Giulia in the Northeast and Basilicata in the South. Two hundred and seventy-nine mothers of infants and children 6 to 23 months of age were interviewed using an 85-item questionnaire including closed and open questions on infant feeding experiences and beliefs, sources of information and support, reasons for intended and actual choices and practices, and some demographic and social variables. Face-to-face interviews were conducted between May 2001 and September 2002. Quantitative and qualitative methods were used for data analysis.

Results

The distribution of the mothers by age, education, employment and parity did not differ from that of the general population of the two regions. The reported rates of initiation and duration of breastfeeding were also similar: 95% started breastfeeding, exclusive breastfeeding was 32% at three and 9% at six months, with 64% and 35% of any breastfeeding, respectively. Some differences were reported in the rates of full breastfeeding, reflecting different ages of introduction of non-nutritive fluids. These, as well as nutritive fluids – including infant formula – and complementary foods, were introduced far too early. Advice on infant feeding was generally provided by health professionals and often was not based on up-to-date recommendations. Mothers were generally aware of the advantages of breastfeeding, but at the same time reported problems that they were not able to solve alone or through social and health system support. Most mothers would welcome the support of a peer counsellor. More mothers in Basilicata than in Friuli Venezia Giulia reported difficulties with breastfeeding related to returning to work and were not familiar with their rights on breastfeeding and maternity leave.

Conclusion

Programmes for the protection, promotion and support of breastfeeding in these and similar regions of Italy should concentrate on better training of health professionals with regards to lactation management, communication, and counselling skills. The addition of trained peer counsellors could reinforce the work done by the health system and, through community involvement, could help change social prejudice in the mid- and long-term. The differences between regions should be taken into account in formulating these programmes to avoid increasing, and possibly to decrease, the current gaps.  相似文献   
9.
In previous studies in rats and goats, hydrophilic compositions of the PEOT/PBT block copolymer family have shown in vivo calcification and bone bonding. These copolymers are therefore interesting candidates as scaffolding materials in bone tissue engineering applications. Model studies using goat bone marrow stromal cells, however, showed that it was not possible to culture bone marrow stromal cells in vitro on these hydrophilic copolymers. In this paper two ways of surface modifying these materials to improve in vitro bone marrow stromal cell attachment and growth are discussed. Two different approaches are described: (1) blending of hydroxyapatite (HA) followed by CO(2) gas plasma etching; (2) surface modification using CO(2) gas plasma treatments. It was observed that not only HA but also the CO(2) plasma treatment by itself has a positive effect on bone marrow stromal cell attachment and growth. Gas plasma treatment appeared to be the most successful approach, resulting in a large increase in the amount of bone marrow stromal cells present on the surface (determined by a DNA assay). The amount of DNA present on the plasma-treated copolymer 1000/70/30 PEOT/PBT, based on poly(ethylene oxide, M(w) = 1000, 70 m% soft segment), was comparable to the amount present on PDLLA and significantly higher than the amount present on PCL after 7 days of cell culturing. The fact that after gas plasma treatment bone marrow stromal cells do attach to PEOT/PBT copolymers, enables in vitro bone marrow stromal cell culturing, making bone tissue engineering applications of these materials possible.  相似文献   
10.
As stem cells undergo differentiation, mitochondrial DNA (mtDNA) copy number is strictly regulated in order that specialized cells can generate appropriate levels of adenosine triphosphate (ATP) through oxidative phosphorylation (OXPHOS) to undertake their specific functions. It is not understood whether tumor-initiating cells regulate their mtDNA in a similar manner or whether mtDNA is essential for tumorigenesis. We show that human neural stem cells (hNSCs) increased their mtDNA content during differentiation in a process that was mediated by a synergistic relationship between the nuclear and mitochondrial genomes and results in increased respiratory capacity. Differentiating multipotent glioblastoma cells failed to match the expansion in mtDNA copy number, patterns of gene expression and increased respiratory capacity observed in hNSCs. Partial depletion of glioblastoma cell mtDNA rescued mtDNA replication events and enhanced cell differentiation. However, prolonged depletion resulted in impaired mtDNA replication, reduced proliferation and induced the expression of early developmental and pro-survival markers including POU class 5 homeobox 1 (OCT4) and sonic hedgehog (SHH). The transfer of glioblastoma cells depleted to varying degrees of their mtDNA content into immunocompromised mice resulted in tumors requiring significantly longer to form compared with non-depleted cells. The number of tumors formed and the time to tumor formation was relative to the degree of mtDNA depletion. The tumors derived from mtDNA depleted glioblastoma cells recovered their mtDNA copy number as part of the tumor formation process. These outcomes demonstrate the importance of mtDNA to the initiation and maintenance of tumorigenesis in glioblastoma multiforme.  相似文献   
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