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This study was conducted at Belen de Escobar, Argentina, in March and April 1987. Experimental work on synchronization of estrus, deep-freeze conservation of ram semen and small fertility trials involving cervical and intrauterine (i.u.) insemination methods was undertaken. A total of 80 Corriedale ewes were used in seven insemination trials. Insemination trials were grouped into two experimental groups for comparison of 1) frozen semen diluted with an experimental extender and a control diluent inseminated cervically or i.u. in synchronized/superovulated ewes and 2) cervical insemination of fresh diluted or frozen semen in ewes inseminated at natural estrus or in ewes that were synchronized/superovulated. An overall ovulation rate of 8.7 +/- 0.5 was obtained by using a superovulatory regimen consisting of 3 mg Norgestomet implants and a total dose of 18 mg follicle stimulating hormone-pituitary (FSH-P). Numbers of ova recovered per ewe following superovulation ranged from 4.3 to 5.4. In experimental Group I, fertilization rates improved when laparoscopic intrauterine AI was used compared with cervical insemination (P<0.05). Fertility rates of i.u. and cervical insemination of frozen semen diluted with the experimental extender showed satisfactory fertilizing capacity. In experimental Group II, a lower number of fertilized ova were recovered from ewes inseminated with frozen semen (P<0.02), irrespective of their estrus manipulation.  相似文献   
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We evaluated in a double-blind study the bronchodilatory properties of 2-decarboxy-2-hydroxymethyl prostaglandin E1 (PGE1-carbinol), described recently as a nonirritant bronchodilator in animals. Fifteen asthmatic patients received by inhalation single doses of 1, 10, and 30 μg PGE1-carbinol, 55 μg PGE2, and placebo (10% ethanol in normal saline, which was also used as diluent for the PGs). Such pulmonary function tests as forced expiratory volume in 1 second, forced vital capacity, and maximal expiratory flow were monitored during 2 hours following inhalation of each compound. 10 and 30 μg PGE1-carbinol produced significant but short-acting bronchodilation, similar to that caused by 55 μg PGE2. One-third of the patients reported mild cough and throat irritation during and shortly after inhalation of 30 μg PGE1-carbinol or 55 μg PGE2. Placebo and 1 μg PGE1-carbinol produced minimal side effects, but neither agent caused bronchodilation. In an adjunctive, unblinded trial, the same patients received 400 μg fenoterol. Fenoterol caused greater bronchodilation 15 and 30 minutes after inhalation than did the PGs in the double-blind study.  相似文献   
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In contact experiments with different experimental conditions, electrochemical Ag+ solutions exhibited better antimicrobial effectiveness against bacteria, a yeast species, and a mold than did analogous silver solutions from inorganic salts. The particular characteristics of electrochemical Ag+, such as the mode of action, effectiveness at low concentrations, and stability, indicate that Ag+ could be used effectively in preservatives.  相似文献   
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Three analogues of the tridecapeptide amide H-Leu-(Glu)5-Ala-Tyr-Gly-Nle-Asp-Phe-NH2 were synthetized with alpha-deuterated glutamate residues in specific positions in order to assign unambiguously the 1H nmr spectrum of the parent peptide in water and in water-trifluoroethanol mixtures. The synthetic route is described and the assignment illustrated. A previous, tentative assignment based solely on indirect evidence [Mammi, S., Mammi, N. J. & Peggion, E. (1988) Biochemistry 27, 1374-1379] was partially modified.  相似文献   
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The establishment of permanent T-lymphocyte cell lines by transformation with DNA viruses has not yet been achieved. This paper reports the successful transfer of polyoma virus genome into T-lymphocyte cells by somatic hybridization. A T-lymphocyte clone, HB1, derived from (DBA/ 2J×AKR) spleen cells, isolated in vitro by cloning in semi-solid agar, was fused with a polyoma (Py) virus-transformed fibroblast C3HPy, clone 1. The authenticity of the hybrid C3H/HB was established by chromosome and histocompatibility antigen studies. This initial population and the various clones retained T-lymphocyte characteristics such as morphological appearance, growth properties (suspension culture) and differentiation antigen (Thy 1–2). The hybrid cell line and the various clones presented all the characteristics of Py transformation. Namely, they carried the Py genome originating from the fibroblastic parent and maintained Py virus tumour-associated antigens (TSTA, TSSA and T antigens). In most respects, this hybrid population resembled the C3HPy/C11 parent and exhibited the same tumorigenicity.  相似文献   
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Purpose

PP2A is a serine/threonine phosphatase critical to physiological processes, including apoptosis. Cell penetrating peptides are molecules that can translocate into cells without causing membrane damage. Our goal was to develop cell-penetrating fusion peptides specifically designed to disrupt the caspase-9/PP2A interaction and evaluate their therapeutic potential in vitro and in vivo.

Experimental Design

We generated a peptide containing a penetrating sequence associated to the interaction motif between human caspase-9 and PP2A (DPT-C9h), in order to target their association. Using tumour cell lines, primary human cells and primary human breast cancer (BC) xenografts, we investigated the capacity of DPT-C9h to provoke apoptosis in vitro and inhibition of tumour growth (TGI) in vivo. DPT-C9h was intraperitonealy administered at doses from 1 to 25 mg/kg/day for 5 weeks. Relative Tumour Volume (RTV) was calculated.

Results

We demonstrated that DPT-C9h specifically target caspase-9/PP2A interaction in vitro and in vivo and induced caspase-9-dependent apoptosis in cancer cell lines. DPT-C9h also induced significant TGI in BC xenografts models. The mouse-specific peptide DPT-C9 also induced TGI in lung (K-Ras model) and breast cancer (PyMT) models. DPT-C9h has a specific effect on transformed B cells isolated from chronic lymphocytic leukemia patients without any effect on primary healthy cells. Finally, neither toxicity nor immunogenic responses were observed.

Conclusion

Using the cell-penetrating peptides blocking caspase-9/PP2A interactions, we have demonstrated that DPT-C9h had a strong therapeutic effect in vitro and in vivo in mouse models of tumour progression.  相似文献   
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As the scientific distinction between climate and weather suggests, knowledge about climate is supposed to be beyond indigenous peoples’ everyday experience of the environment in that it requires a long-term record. On the basis of ethnographic work among geoscientists in Scotland and West Greenland, I show that practitioners of this discipline have mastered the craft of turning ‘visible’ what is ‘invisible’ to the senses by playing with shorter time-scales. In thinking and communicating about the past, geoscientists would compress and accelerate long-term environmental processes, often at the cost of dissociating them from processes occurring at shorter time-scales, particularly the adaptation of living organisms. Attending to the historical circumstances around the development of this skill, I argue that it relates to an ideal of objectivity in science that corresponds to an optical understanding of time, inspired by the image of the telescope. Challenging the distinction between climate and weather, and the epistemic distance on which it rests, I discuss recent approaches in environmental anthropology that have uncritically adopted this distinction to distinguish indigenous knowledge of the environment from climate science. In conclusion, informed by research with indigenous peoples of the Arctic, I speculate on alternative ways of understanding climate knowledge, beyond the climate-weather distinction.  相似文献   
10.
We present a robust and general shotgun glycoproteomics approach to comprehensively profile glycoproteins in complex biological mixtures. In this approach, glycopeptides derived from glycoproteins are enriched by selective capture onto a solid support using hydrazide chemistry followed by enzymatic release of the peptides and subsequent analysis by tandem mass spectrometry. The approach was validated using standard protein mixtures that resulted in a close to 100% capture efficiency. Our capture approach was then applied to microsomal fractions of the cisplatin-resistant ovarian cancer cell line IGROV-1/CP. With a Protein Prophet probability value greater than 0.9, we identified a total of 302 proteins with an average protein identification rate of 136 +/- 19 (n = 4) in a single linear quadrupole ion trap (LTQ) mass spectrometer nano-LC-MS experiment and a selectivity of 91 +/- 1.6% (n = 4) for the N-linked glycoconsensus sequence. Our method has several advantages. 1) Digestion of proteins initially into peptides improves the solubility of large membrane proteins and exposes all of the glycosylation sites to ensure equal accessibility to capture reagents. 2) Capturing glycosylated peptides can effectively reduce sample complexity and at the same time increase the confidence of MS-based protein identifications (more potential peptide identifications per protein). 3) The utility of sodium sulfite as a quencher in our capture approach to replace the solid phase extraction step in an earlier glycoprotein chemical capture approach for removing excess sodium periodate allows the overall capture procedure to be completed in a single vessel. This improvement minimizes sample loss, increases sensitivity, and makes our protocol amenable for high throughput implementation, a feature that is essential for biomarker identification and validation of a large number of clinical samples. 4) The approach is demonstrated here on the analysis of N-linked glycopeptides; however, it can be applied equally well to O-glycoprotein analysis.  相似文献   
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