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1.
Congenital malformations may occur during early embryogenesis in cases of genetic abnormalities or various environmental factors. Affected subjects most often have only one or 2 abnormalities; subjects rarely have several unrelated congenital defects. Here we describe a case of a stillborn New Zealand white rabbit with multiple complex congenital malformations, including synophthalmia, holoprosencephaly, gastroschisis, and a supernumerary hindlimb, among other anomalies. There was no historical exposure to teratogens or other known environmental causes. Although not confirmed, this case was most likely a rare spontaneous genetic event.Congenital malformations occur when there is derangement of the embryologic developmental process. Neural development and organogenesis is a critical time of development that occurs during early embryogenesis.2,37 Congenital malformations that manifest at this stage of development may occur in association with various genetic abnormalities, such as point mutations and chromosomal abnormalities.25,29 In addition, environmental factors, including maternal health status, nutritional deficiencies, and exposure to teratogenic drugs or chemicals, may play a role in the development of congenital malformations.12,25 However, in 65% to 75% of human cases, the cause is unknown, resulting from a complex set of events such as polygenic or multifactorial genetic disorders, spontaneous genetic errors, and synergistic interactions of teratogens.3,25 Approximately 78% of human cases demonstrate only a single developmental malformation, with cardiovascular defects accounting for approximately 30% to 35% of organ defects. Cases of more than 2 or 3 malformations in a single person are extremely rare.28Here we describe a New Zealand white rabbit that was stillborn with numerous complex developmental abnormalities, including synophthalmia, a supraoptic proboscis, holoprosencephaly with other associated craniofacial deformities, Chiari malformation type I, gastroschisis, a supernumerary hindlimb, a fused (horseshoe) kidney with a supernumerary kidney, and male pseudohermaphroditism.  相似文献   
2.
Lu  Chongchong  Liu  Haifeng  Jiang  Depeng  Wang  Lulu  Jiang  Yanke  Tang  Shuya  Hou  Xuwen  Han  Xinyi  Liu  Zhiguang  Zhang  Min  Chu  Zhaohui  Ding  Xinhua 《Plant and Soil》2019,445(1-2):383-396
Plant and Soil - There are growing concerns regarding the restoration of karst rocky desertification (KRD) areas. However, the soil conditions and its residing microorganisms, which are essential...  相似文献   
3.
猪O型口蹄疫病毒细菌样颗粒疫苗的制备与免疫原性鉴定   总被引:1,自引:0,他引:1  
验证基于革兰氏阳性增强基质(Gram-positive enhancer matrix,GEM)展示口蹄疫病毒细菌样颗粒(Bacteria-like particles,BLP)疫苗的可行性。按照大肠杆菌偏好性密码子优化合成基于猪口蹄疫病毒Mya98株序列的3种抗原基因设计,并将其插入到含有锚钩蛋白基因的原核表达载体p QZ-PA,鉴定阳性后转入Escherichia coli BL21,进行诱导表达。利用SDS-PAGE与Western blotting对目的基因表达及产物的可溶性进行分析。利用GEM颗粒纯化目的蛋白,制备细菌样颗粒疫苗抗原;利用BCA试剂盒测定重组蛋白的浓度,将重组蛋白与白油佐剂乳化,制备疫苗,免疫5周龄小鼠,同时设商品化多肽苗对照与空白对照,免疫后不同时间采集试验小鼠血清,利用口蹄疫病毒多肽ELISA抗体检测试剂盒和O型口蹄疫抗体液相阻断酶联免疫(Enzyme-linked immunosorbent assay,ELISA)检测试剂盒检测免疫小鼠血清的抗体水平;利用噻唑蓝比色法(Methylthiazolyldiphenyl-tetrazolium bromide,MTT)测定淋巴细胞增殖情况;利用荧光定量PCR方法检测相关细胞因子表达,评价细胞免疫水平。SDS-PAGE结果表明,设计在大肠杆菌中的3种口蹄疫病毒抗原基因均以可溶形式获得高效表达;Western blotting结果显示,表达的重组蛋白能够与口蹄疫病毒阳性血清发生反应,利用GEM颗粒能够实现重组蛋白的一步离心纯化,制备BLP疫苗抗原;免疫试验结果表明,设计的重组抗原B(T1BT2)4B不但能够刺激免疫小鼠产生更高水平的多肽特异性ELISA抗体与口蹄疫特异性液相阻断抗体,而且产生了更高水平的脾淋巴细胞增殖及Th1型的细胞因子分泌。初步实验结果表明,本研究制备的BLP疫苗GEM-B(T1BT2)4B具有良好的免疫原性,为研究口蹄疫病毒基因工程亚单位疫苗开辟了一条新的思路。  相似文献   
4.
Gamma‐aminobutyric acid (GABA) is an important metabolite which functions in plant growth, development, and stress responses. However, its role in plant defense and how it is regulated are largely unknown. Here, we report a detailed analysis of GABA induction during the resistance response to Pseudomonas syringae in Arabidopsis thaliana. While searching for the mechanism underlying the pathogen‐responsive mitogen‐activated protein kinase (MPK)3/MPK6 signaling cascade in plant immunity, we found that activation of MPK3/MPK6 greatly induced GABA biosynthesis, which is dependent on the glutamate decarboxylase genes GAD1 and GAD4. Inoculation with Pseudomonas syringae pv tomato DC3000 (Pst) and Pst‐avrRpt2 expressing the avrRpt2 effector gene induced GAD1 and GAD4 gene expression and increased the levels of GABA. Genetic evidence revealed that GAD1, GAD2, and GAD4 play important roles in both GABA biosynthesis and plant resistance in response to Pst‐avrRpt2 infection. The gad1/2/4 triple and gad1/2/4/5 quadruple mutants, in which the GABA levels were extremely low, were more susceptible to both Pst and Pst‐avrRpt2. Functional loss of MPK3/MPK6, or their upstream MKK4/MKK5, or their downstream substrate WRKY33 suppressed the induction of GAD1 and GAD4 expression after Pst‐avrRpt2 treatment. Our findings shed light on both the regulation and role of GABA in the plant immunity to a bacterial pathogen.  相似文献   
5.
Human tumor necrosis factor a (hTNFa), a pleiotropic cytokine with activities ranging from host defense mechanisms in infection and injury to severe toxicity in septic shock or other related diseases, is a promising target for drug screening. Using the SELEX (systematic evolution of ligands by exponential enrichment) process, we isolated oligonucleotide ligands (aptamers) with high affinities for hTNFa. Aptamers were selected from a starting pool of 40 randomized sequences composed of about 1015 RNA molecules. Representative aptamers were truncated to the minimal length with high affinity for hTNFa and were further modified by replacement of 2'-OH with 2'-F and 2'-NH2 at all ribopurine positions. These modified RNA aptamers were resistant to nuclease. The specificity of these aptamers for hTNFa was confirmed, and their activity to inhibit the cytotoxicity of hTNFa on mouse L929 cells was determined. Results demonstrated that four 2'-NH2-modified aptamers bound to hTNFa with high affinity and blocked the  相似文献   
6.
Experiments were conducted to measure the suction volume of silver carp and bighead carp of age 1 + with respiratory chamber, and to calculate the suction volume and the filtering efficiency with respect to changes in concentrations of food particles. Suction volume (B. ml/mouth) and filtering efficiency (E. %) were calculated using the following formula: C 1=C0(1-BE/v)n where C0 and C1 were the concentrations of specific food particles at the beginning and at the end of experiment, respectively, V was the volume (ml) of experimental water, and n was the total number of observation of suction made during the experimental period. The relationships between suction volume (ml/mouth) of age I+ silver carp (Bh) and bighead carp (Ba) and their standard lengths (L, cm) were: B h=0.561L-8.94, Ba= 0.627L-7.48 while those of the fingerlings were: B h= O.l70L-0.837, Ba= 0.157L-0.418. The suction volume of the fingerlings was mainly affected by fish size, the function of temperature between 15 and 25° C being negligible. However, temperature affected filtering rate (filtered volume per unit time) through its effect on filtering frequency. The filtering efficiency of the fishes for rotifers (Brachionus caliciflorus) was 100 per cent. The relationships between filtering efficiency and sizes of food particles smaller than or equal to that of a rotifer were: E h=25.1 ln e.s.d. -13.6, Ea=22.2 In e.s.d. -33.1 where Eh and Ea were filtering efficiency of silver carp and bighead carp, respectively, and e.s.d. was the equivalent spherical diameter (μm) of food particles.  相似文献   
7.
Anesthetic agents prolong cardiac repolarization by blocking ion currents. However, the clinical relevance of this blockade in subjects with reduced repolarization reserve is unknown. We have generated transgenic long QT syndromes type 1 (LQT1) and type 2 (LQT2) rabbits that lack slow delayed rectifier K+ currents (IKs) or rapidly activating K+ currents (IKr) and used them as a model system to detect the channel-blocking properties of anesthetic agents. Therefore, LQT1, LQT2, and littermate control (LMC) rabbits were administered isoflurane, thiopental, midazolam, propofol, or ketamine, and surface ECGs were analyzed. Genotype-specific heart rate correction formulas were used to determine the expected QT interval at a given heart rate. The QT index (QTi) was calculated as percentage of the observed QT/expected QT. Isoflurane, a drug that blocks IKs) prolonged the QTi only in LQT2 and LMC but not in LQT1 rabbits. Midazolam, which blocks inward rectifier K+ current (IK1), prolonged the QTi in both LQT1 and LQT2 but not in LMC. Thiopental, which blocks both IKs and IK1, increased the QTi in LQT2 and LMC more than in LQT1. By contrast, ketamine, which does not block IKr, IKs, or IK1, did not alter the QTi in any group. Finally, anesthesia with isoflurane or propofol resulted in lethal polymorphic ventricular tachycardia (pVT) in three out of nine LQT2 rabbits. Transgenic LQT1 and LQT2 rabbits could serve as an in vivo model in which to examine the pharmacogenomics of drug-induced QT prolongation of anesthetic agents and their proarrhythmic potential. Transgenic LQT2 rabbits developed pVT under isoflurane and propofol, underlining the proarrhythmic risk of IKs blockers in subjects with reduced IKr.  相似文献   
8.
Ba M  Kong M  Yu G  Sun X  Liu Z  Wang X 《Neurochemical research》2011,36(6):1135-1144
The phosphorylation of glutamate receptor 1 (GluR1) has been increasingly implicated in the formation and maintenance of plastic responses. To investigate molecular mechanisms that underlie the persisting alterations in motor response occurring with levodopa treatment of parkinsonian patients, we evaluated the time course of these changes in relation to the phosphorylation of GluR1 in 6-hydroxydopamine (6-OHDA) lesioned animals. Three weeks of twice-daily levodopa administration to rats shortened the duration of the rotational responses and increased the peak turning responses, which lasted at least 7 days after withdrawal of chronic levodopa treatment. The shortened response duration and increased peak turning, resembling human wearing-off fluctuations and dyskinesia, were associated with a marked increase in Ser-845 phosphorylated GluR1 (pGluR1S845) immunoreactivity in lesioned striatum in response to levodopa treatment. The time course of changes in GluR1 phosphorylation correlated with the time course of changes in motor behavior after withdrawal of chronic levodopa therapy. Our immunostaining data showed that these changes were confined to parvalbumin-positive neurons where GluR1 are exclusively expressed. Both the altered motor response and the degree of pGluR1S845 were attenuated by the intrastriatal administration of protein kinase A (PKA) inhibitor Rp-cAMPS or GluR1 antisense oligonucleotides. The results suggest that Ser-845 GluR1 phosphorylation within parvalbumin-positive neurons contributes to the persistence of the motor response alterations produced by chronic intermittent dopaminergic stimulation.  相似文献   
9.

Aim

To assess the efficacy of a biodegradable, prednisolone acetate implant in a rabbit uveitis model.

Methods

Randomized, controlled study of biodegradable microfilms preloaded with prednisolone acetate (PA) in a rabbit uveitis model. Experimental uveitis was induced by unilateral intravitreal injection of Mycobacterium tuberculosis H37Ra antigen (50 ug; 1 ug/uL) in preimmunized rabbits. PA-loaded poly[d,l-lactide-co-ε-caprolactone] (PLC) microfilms (n = 10) and blank microfilms (n = 6) were implanted subconjunctivally. An estimate of PA release in vivo was calculated from measured residual PA amounts in microfilms after the rabbits were sacrificed. The eyes were clinically monitored for ocular inflammation for 28 days. Histopathological examination of the enucleated eyes was performed at the end of the study period.

Results

In vitro studies revealed that sandwich PA-loaded microfilm formulations exhibited higher release kinetic compared to homogenous PA-loaded microfilms. The 60–40–60% microfilm released an average of 0.034 mg/day of PA over the period of 60 days in vitro; and we found that approximately 0.12 mg/day PA was released in vivo. Animals implanted with the PA-loaded microfilms exhibited significantly lowered median inflammatory scores when compared against the control group in this model for recurrent uveitis (P<0.001). The implants were clinically well tolerated by all the animals. Histology results showed no significant scarring or inflammation around the PA-loaded microfilms.

Conclusion

Our pilot study demonstrated that a subconjunctival PA-loaded implant is effective in suppressing inflammation in the rabbit model of uveitis, by providing therapeutic levels of PA that attenuated the inflammatory response even after a rechallenge. Longer term studies are now needed to establish the therapeutic potential of such a delivery system for treatment of ocular inflammation.  相似文献   
10.
Facing the trend of increasing population, how to increase maize grain yield is a very important issue to ensure food security. In this study, 28 nationally approved maize hybrids were evaluated across 24 different climatic conditions for two consecutive years (2018–2019). The purpose of this study was to select high-yield with stable genotypes and identify important agronomic traits for maize breeding program improvement. The results of this study showed that the genotype ╳ environment interaction effects of the 12 evaluated agronomic traits was highly significant (P < 0.001). We introduced a novel multi-trait genotype-ideotype distance index (MGIDI) to select genotypes based on multiple agronomic traits. The selection process exhibited by this method is unique and easy to understand, so the MGIDI index will have more and more important applications in future multi-environment trials (METs) research. The genotypes selected by the MGIDI index were G22, G10, G12 and G1 as the high yielding and stable genotypes. The parents of these selected genotypes have the ability to play a greater role as the basic germplasm in the breeding process. A new form of genotype (G) main effects and genotype (G) -by-environment (E) interaction (GGE) technician, genotype*yield*trait (GYT) biplot, based on multiple traits for genotypes selection was also applied in this study. The GYT biplot ranked genotypes by combining grain yield with other evaluated agronomic traits, and displayed the distribution of their traits, namely strengths and weaknesses.  相似文献   
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