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1.
Cell therapy of heart failure   总被引:1,自引:0,他引:1  
Together with angiogenesis and gene therapy, cell transplantation is one of the newest treatments that have been proposed to improve the still grim outcome of patients with cardiac failure. The underlying rationale is that implantation of contractile cells into fibrous post-infarction scar can functionally 'regenerate' these areas. Primarily for practical reasons, autologous skeletal myoblasts have been the first to be tested in a clinical trial but other cell types can be considered, among which bone marrow stromal and hematopoietic stem cells are of particular interest because of their autologous origin and their purported transdifferentiation potential into cardiac and/or endothelial cells. However, several key issues still need to be addressed, including (i) the optimal type of donor cells, (ii) the mechanism by which cell engraftment improves cardiac function, actively (i.e., by increasing contractility) or passively (i.e. by limiting infarct expansion and remodelling), (iii) the optimisation of cell survival, and (iiii) the potential benefits of cell transplantation in non-ischaemic heart failure. Parallel to the numerous experimental studies designed to address these issues, initial clinical trials are underway or in preparation and, if properly designed and conducted, should allow to know whether the hopes raised by cellular therapy are met by clinically meaningful improvements in the outcomes of patients with heart failure.  相似文献   

2.
3.
In captivity, male bonnet macaques (Macaca radiata) frequently express "friendship" toward one another, including affiliative behavior such as huddling, grooming, coalitionary support, and sitting in close proximity. The purpose of this study was to determine whether wild adult male bonnet macaques also express "friendship" by investigating whether or not (1) adult male bonnet macaques have affiliative social relationships with other males, (2) the strength of social relationships varies among dyads, (3) there is time-matched reciprocity in allogrooming among dyads, and if so, whether the level of reciprocity occurs within a bout of grooming, a day, or over 2 months (the limit of this study), and (4) a correlation exists between the strength of social relationships and dominance ranks among adult males. Focal samples totaling 150 hr on all seven adult males in one study group were conducted to record both agonistic and affiliative interactions. Agonistic interactions were used to construct a dominance hierarchy, whereas affiliative interactions (sitting in proximity to within 1 m with and without grooming) were used to quantify the existence and strength of social bonds within dyads. Results show that adult male bonnet macaques had differentiated affiliative relationships with other males in their group. There was little reciprocity of grooming within a bout of grooming or within a day, but greater reciprocity over the study period of 2 months. There was no correlation between dominance ranking distance and the strength of affiliative relationship within dyads; however, within dyads lower-ranking males groomed higher-ranking males more than vice versa. This study suggests that friendships in male bonnet macaques are characterized not by immediate tit-for-tat reciprocal altruism, but by reciprocity over a longer time span, and that affiliative social relationships may be less constrained by agonistic relationships than is the case in more despotic species of macaques.  相似文献   

4.
Successful pregnancy is dependent upon the implantation of a competent embryo into a receptive endometrium. Despite major advancement in our understanding of reproductive medicine over the last few decades, implantation failure still occurs in both normal pregnancies and those created artificially by assisted reproductive technology (ART). Consequently, there is significant interest in elucidating the etiology of implantation failure. The complex multistep process of implantation begins when the developing embryo first makes contact with the plasma membrane of epithelial cells within the uterine environment. However, although this biological interaction marks the beginning of a fundamental developmental process, our knowledge of the intricate physiological and molecular processes involved remains sparse. In this synopsis, we aim to provide an overview of our current understanding of the morphological changes which occur to the plasma membrane of the uterine endothelium, and the molecular mechanisms that control communication between the early embryo and the endometrium during implantation. A multitude of molecular factors have been implicated in this complex process, including endometrial integrins, extracellular matrix molecules, adhesion molecules, growth factors, and ion channels. We also explore the development of in vitro models for embryo implantation to help researchers investigate mechanisms which may underlie implantation failure. Understanding the precise molecular pathways associated with implantation failure could help us to generate new prognostic/diagnostic biomarkers, and may identify novel therapeutic targets. Birth Defects Research (Part C) 108:19–32, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   

5.
Asian nonhuman primates were surveyed seroepidemiologically for natural infection with human T-cell leukemia virus (ATLV/HTLV) or a closely related agent. Materials from various primates (three genera [Macaca, Presbytis, and Hylobates], 17 species, totalling 1,079 animals) under natural conditions were obtained in the field study. Virus infection was determined by the indirect immunofluorescence test using HTLV-specific antigens. Animals seropositive for HTLV were found only among macaques originating from various localities, toque monkeys in Sri Lanka (17.5%), crab-eating macaques in Thailand (1.3%), stumptailed macaques in Thailand (1.5%), rhesus monkeys in Thailand (3.3%), and Celebes macaques in Indonesia (16.9%). Langurs and gibbons were seronegative. Thus the wide distribution of HTLV in nature among various macaques suggests that the introduction of this virus into primates occurred in ancient times.  相似文献   

6.
IntroductionThe efficacy of catheter ablation in patients with low cardiac function has been previously reported; however, only a few studies have included mid-range ejection fraction (mrEF). This study aimed to evaluate the efficacy and safety of atrial fibrillation (AF) ablation in patients with left ventricular ejection fraction (LVEF) < 50%.MethodsThis study retrospectively analyzed 79 patients (reduced ejection fraction [rEF]/mrEF, 38/41; paroxysmal/persistent, 37/42; heart failure hospitalizations within one year before ablation, 36 [45.6%]) who underwent the first ablation procedure at our hospital from April 2017 to December 2021. Radiofrequency ablation and cryoablation were performed for 69 and 10 patients, respectively.ResultsComplications included pacemaker implantation for postoperative sick sinus syndrome in one patient and inguinal hematoma in one patient. Regarding efficacy, there were significant postoperative improvements in echocardiographic data, blood test values, and diuretic use. After a mean follow-up of 60 months, 86.1% patients had no AF recurrence. There were 9 heart failure hospitalizations (11.4%) and 5 all-cause deaths (6.3%); no significant differences were found between the rEF and mrEF groups. No significant predictors of AF recurrence were found in preoperative patient characteristics.ConclusionAF ablation in patients with LVEF <50% significantly improved cardiac and renal functions with few complications, resulting in a high non-recurrence rate and reduced heart failure.  相似文献   

7.
Several macaques species are used for HIV pathogenesis and vaccine studies, and the characterization of their major histocompatibility complex (MHC) class I genes is required to rigorously evaluate the cellular immune responses induced after immunization and/or infection. In this study, we demonstrate that the gene expressing the Mane-A*06 allele of pig-tailed macaques is an orthologue of the locus encoding the Mamu-A*05 allele family in rhesus macaques. Analysis of the distribution of this locus in a cohort of 63 pig-tailed macaques revealed that it encodes an oligomorphic family of alleles, highly prevalent (90%) in the pig-tailed macaque population. Similarly, this locus was very frequently found (62%) in a cohort of 80 Indian rhesus macaques. An orthologous gene was also detected in cynomolgus monkeys originating from four different geographical locations, but was absent in two African monkey species. Expression analysis in pig-tailed macaques revealed that the Mane-A*06 alleles encoded by this locus are transcribed at 10- to 20-fold lower levels than other MHC-A alleles (Mane-A*03 or Mane-A*10). Despite their conservation and high prevalence among Asian macaque species, the alleles of the Mane-A*06 family and, by extension their orthologues in rhesus and cynomolgus monkeys, may only modestly contribute to cellular immune responses in macaques because of their low level of expression.  相似文献   

8.
中国部分地区实验猕猴巴尔通体感染状况及其遗传特征   总被引:1,自引:0,他引:1  
【目的】五日热巴尔通体(Bartonella quintana)由体虱在人群中传播,可引起多种人类疾病包括战壕热。为进一步搜集猕猴是五日热巴尔通体自然宿主的证据,本研究调查了国内4个地区实验用猕猴五日热巴尔通体的感染状况,对菌株遗传特征进行了分析。【方法】采集猕猴全血和血清样品各550份,用于菌株分离、核酸和血清IgG抗体检测。应用6个管家基因扩增及测序方法进行菌株鉴定、系统发育及核苷酸多态性分析;应用随机扩增多态性DNA标记(Random amplified polymorphic DNA,RAPD)技术分析不同宿主来源菌株RAPD指纹图谱差异;应用间接免疫荧光法(Indirect immunofluorescence assay,IFA)检测血清中抗五日热巴尔通体IgG抗体水平。【结果】从550只猕猴中分离到8株五日热巴尔通体菌株,带菌率为1.5%;直接PCR检测550份全血核酸的总感染率为8.2%。普通猕猴血清阳性率为19.0%,感染水平明显高于食蟹猕猴(5.6%)。五日热巴尔通体与汉赛巴尔通体RAPD指纹图谱的带型完全不同,猴源和人源五日热巴尔通体菌株Fuller带型基本一致。不同宿主来源菌株核苷酸多态性分析显示,猴源菌株之间差异小,其与人源菌株差异较大。【结论】中国猕猴五日热巴尔通体感染水平较高,普通猕猴自然感染率及抗体水平明显高于食蟹猕猴,猴源与人源菌株的基因型有明显差异。  相似文献   

9.
A. S. Trimble  L. L. Black  H. E. Aldridge 《CMAJ》1972,107(7):649-651,653
Saphenous vein bypass grafting is a recent and important procedure in the management of atherosclerotic coronary artery disease. A review of the first 150 patients operated on to July 1971 at the Toronto General Hospital is presented. Many had multiple bypass grafts and some had additional procedures including internal mammary artery implantation, valve replacement and scar tissue resection. There were five operative deaths (3%) and an additional five hospital deaths; the majority were related to myocardial infarction.A clinical review of the results six months to three years after operation indicates marked improvement in over 80% of the survivors. Postoperative hemodynamic studies were performed in many. It is suggested that patients with poor myocardial function presenting in failure may not benefit from the operation.  相似文献   

10.
Using continuous video recording, we identified predation as the main cause of nest failure of understorey‐nesting birds in an intact evergreen forest in northeastern Thailand. Our dataset of 87 predation events is the largest recorded in the tropics. The main predators were macaques (n = 38; 43.7%), nocturnal snakes (n = 19; 21.8%), non‐raptorial birds (n = 12; 13.8%), raptors (n = 6; 6.9%), squirrels (n = 5; 5.7%) and tree shrews (n = 4; 4.6%). The two most important predators, Pig‐tailed Macaque Macaca nemistrina and Green Cat Snake Boiga cinerea, showed no preference for nest type, nest stage or nest height and we found no difference in their relative predation rates among years. Predation was predominantly diurnal (73.6%), suggesting that visual cues may be important for predators at this site.  相似文献   

11.
Bartonella quintana is a bacterium that causes a broad spectrum of diseases in humans including trench fever. Humans were previously considered to be the primary, if not the only, reservoir hosts for B. quintana. To identify the animal reservoir and extend our understanding of the ecological and evolutionary history of B. quintana, we examined blood samples from macaques and performed multilocus sequence typing (MLST) analysis. We demonstrated the prevalence of B. quintana infection was common in macaques from main primate centres in mainland China. Overall, 18.0% (59/328) of rhesus macaques and 12.7% (39/308) of cynomolgus macaques were found to be infected with B. quintana by blood culture and/or polymerase chain reaction. The infection was more frequently identified in juvenile and young monkeys compared with adult animals. In contrast with the relatively low level of sequence divergence of B. quintana reported in humans, our investigation revealed much higher genetic diversity in nonhuman primates. We identified 44 new nucleotide variable sites and 14 novel sequence types (STs) among the B. quintana isolates by MLST analysis. Some STs were found only in cynomolgus macaques, while some others were detected only in rhesus macaques, suggesting evidence of host‐cospeciation, which were further confirmed by phylogenetic analysis and Splits decomposition analysis. Our findings suggest that trench fever may primarily be a zoonotic disease with macaques as the natural hosts.  相似文献   

12.
DNA was extracted from the buffy coats or serum of 212 rhesus macaques (Macaca mulatta) sampled throughout the species' geographic range. An 835 base pair (bp) fragment of mitochondrial DNA (mtDNA) was amplified from each sample, sequenced, aligned, and used to estimate genetic distances from which phylogenetic trees were constructed. A tree that included sequences from rhesus macaques whose exact origins in China are known was used to determine the regional origin of clusters of haplotypes, or haplogroups, defined by the trees. Indian rhesus sequences formed one large homogeneous haplogroup with very low levels of nucleotide diversity and no geographic structure, and a second much smaller haplogroup apparently derived from Burma. The sequences from Burma and eastern and western China were quite divergent from those in the major haplogroup of India. Each of these sequences formed separate clusters of haplotypes that exhibited far greater nucleotide diversity and/or population structure. Correspondingly, sequences from Indian rhesus macaques that are considered to represent different subspecies (based on morphological differences) were intermingled in the tree, while those from China reflected some, but not all, aspects of subspecific taxonomy. Regional variation contributed 72% toward the paired differences between sequences in an analysis of molecular variance (AMOVA), and the average differences between the populations of eastern and western China were also statistically significant. These results suggest that Indian and Chinese rhesus macaques were reproductively isolated during most, if not all, of the Pleistocene, during which time Indian rhesus macaques experienced a severe genetic bottleneck, and that some gene flow westward into India was subsequently reestablished. Samples from breeding centers in three different provinces of China included sequences from rhesus macaques that originated in both eastern (or southern) and western China, confirming anecdotal reports that regional breeding centers in China exchange breeding stock. Genetic differences among rhesus macaques (even those acquired from the same regional breeding center) that originate in different geographic regions and are employed as subjects in biomedical experiments can contribute to phenotypic differences in the traits under study.  相似文献   

13.
BACKGROUND AND PURPOSE: National Institutes of Health's Division of Comparative Medicine has sponsored a multi-institutional program for the establishment of specific-pathogen-free (SPF) macaque colonies. B virus (Herpesvirus simiae, Cercopithecine herpesvirus type 1) has been targeted in this surveillance. Participating institutions have established individual timetables for frequency of testing and types of monitoring and husbandry techniques, all with the common goal of producing pathogen-free monkeys for research. The greatest biosecurity threat to the program comes from failure to detect seronegative latent infections, either in first-year macaques or macaques introduced in subsequent years, although these are supposed to operate as closed colonies. METHODS: From January 1990 through December 1996, we screened macaques for B virus, using enzyme-linked immunoabsorbant assay (ELISA) and Western blot analysis. RESULTS: During the first year, 1,097 macaques from six colonies were tested, and 88.4% tested negative for B virus. During the seventh year, 1,843 were tested, of which 99.7% tested negative. Seropositive macaques were detected as late as the seventh year. CONCLUSIONS: An aggressive program to establish an SPF colony of captive breeding macaques can be effective in reducing the risk of B-virus exposure.  相似文献   

14.
An 835 base pair (bp) fragment of mitochondrial DNA (mtDNA) was sequenced to characterize genetic variation within and among 1,053 samples comprising five regional populations each of longtail macaques (Macaca fascicularis) and rhesus macaques (Macaca mulatta), and one sample each of Japanese (M. fuscata) and Taiwanese (M. cyclopis) macaques. The mtDNA haplotypes of longtail macaques clustered in two large highly structured clades (Fas1 and Fas2) of a neighbor-joining tree that were reciprocally monophyletic with respect to those representing rhesus macaques, Japanese macaques, and Taiwanese macaques. Both clades exhibited haplotypes of Indonesian and Malaysian longtail macaques widely dispersed throughout them; however, longtail macaques from Indochina, Philippines, and Mauritius each clustered in a separate well-defined clade together with one or a few Malaysian and/or Indonesian longtail macaques, suggesting origins on the Sunda shelf. Longtail macaques from Malaysia and Indonesia were far more genetically diverse, and those from Mauritius were far less diverse than any other population studied. Nucleotide diversity between mtDNA sequences of longtail macaques from different geographic regions is, in some cases, greater than that between Indian and Chinese rhesus macaques. Approximately equal amounts of genetic diversity are due to differences among animals in the same regional population, different regional populations, and different species. A greater proportion of genetic variance was explained by interspecies differences when Japanese and Taiwanese macaques were regarded as regional populations of rhesus macaques than when they were treated as separate species. Rhesus macaques from China were more closely related to both Taiwanese and Japanese macaques than to their own conspecifics from India.  相似文献   

15.
Some breeding facilities in the United States have crossbred Chinese and Indian rhesus macaque (Macaca mulatta) founders either purposefully or inadvertently. Genetic variation that reflects geographic origins among research subjects has the potential to influence experimental outcomes. The use of animals from different geographic regions, their hybrids, and animals of varying degrees of kinship in an experiment can obscure treatment effects under study because high interanimal genetic variance can increase phenotypic variance among the research subjects. The intent of this study, based on a broad genomic analysis of 2,808 single nucleotide polymorphisms (SNPs), is to ensure that only animals estimated to be of pure Indian or Chinese ancestry, based on both demographic and genetic information, are used as sources of infants for derivation and expansion of the California National Primate Research Center's (CNPRC) super‐Specific Pathogen Free (SSPF) rhesus macaque colony. Studies of short tandem repeats (STRs) in Indian and Chinese rhesus macaques have reported that heterozygosity of STRs is higher in Chinese rhesus macaques than in Indian rhesus macaques. The present study shows that heterozygosity of SNPs is actually higher in Indian than in Chinese rhesus macaques and that the Chinese SSPF rhesus macaque colony is far less differentiated from their founders compared to the Indian‐origin animals. The results also reveal no evidence of recent gene flow from long‐tailed and pig‐tailed macaques into the source populations of the SSPF rhesus macaques. This study indicates that many of the long‐tailed macaques held in the CNPRC are closely related individuals. Most polymorphisms shared among the captive rhesus, long‐tailed, and pig‐tailed macaques likely predate the divergence among these groups. Am. J. Primatol. 74:747‐757, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   

16.
It is well known that embryo implantation is a critical process in which embryo should be able to reach and attach to endometrium. Until now, various types of factors are involved in the regulation of this process. S100 proteins are calcium-binding proteins, which have vital roles in embryo implantation and have been considered as possible candidate markers for endometrial receptivity. However, studies regarding mode of actions of these proteins are scarce and more mechanistic insights are needed to clarify exact roles of each one of the S100 protein family. Understanding of function of these proteins in different compartments, stages, and phases of endometrium, could pave the way for conducting studies regarding the therapeutic significance of these proteins in some disorders such as recurrent implantation failure. In this review, we outlined roles and possible underlying mechanisms of S100 protein family in embryo implantation.  相似文献   

17.
We used genotypes for 13 short tandem repeats (STRs) to assess the genetic diversity within and differentiation among populations of rhesus macaques (Macaca mulatta) from mainland Asia and long-tailed macaques (M. fascicularis) from mainland and insular Southeast Asia. The subjects were either recently captured in the wild or derived from wild-caught founders maintained in captivity for biomedical research. A large number of alleles are shared between the 2 macaque species but a significant genetic division between them persists. The distinction is more clear-cut among populations that are not, or are unlikely to have recently been, geographically contiguous. Our results suggest there has been significant interspecific nuclear gene flow between rhesus macaques and long-tailed macaques on the mainland. Comparisons of mainland and island populations of long-tailed macaques reflect marked genetic subdivisions due to barriers to migration. Geographic isolation has restricted gene flow, allowing island populations to become subdivided and genetically differentiated. Indonesian long-tailed macaques show evidence of long-term separation and genetic isolation from the mainland populations, whereas long-tailed macaques from the Philippines and Mauritius both display evidence of founder effects and subsequent isolation, with the impact from genetic drift being more profound in the latter.  相似文献   

18.
Evidence that more people are dying as a result of HIV infection than is reflected by the number of deaths among reported cases meeting the WHO definition of AIDS is derived from mortality data. Ninety-five causes of death likely to be associated with HIV infection were selected. Standardized mortality ratios due to these causes increased for single men aged 15-54 years from 100 in 1984 to 118 in 1987. The age, sex, marital status, temporal and geographic distribution of these excess deaths suggest that they are HIV-associated. It is estimated that 58% of excess deaths due to HIV-related causes were among cases reported to the CDSC AIDS Surveillance Programme in 1987. Some of these deaths may have been among HIV-positive people who did not meet the WHO definition at the time of death. There is a need for surveillance to be extended to include HIV-positive people who die before meeting the WHO definition if the full extent of the HIV epidemic is to be identified.  相似文献   

19.
E. N. MacKay  A. H. Sellers 《CMAJ》1967,96(25):1626-1635
In Ontario, leukemia causes about 4% of all cancer deaths, ranging from nearly 50% at under 5 years of age to 1-3% at age 50 and over. Age-specific death rates are highest among older people; at all ages, male deaths exceed female deaths. Only about 20% of all leukemia patients in Ontario are registered at Ontario Cancer Clinics; the proportion changed sharply with the advent of chemotherapy. For 1258 patients registered in 1938-1963, the crude one-year survival rate was 50%, ranging from 9% for acute leukemia to about 60% for non-acute lymphatic and myeloid leukemia. The long-term outlook was much better for non-acute lymphatic leukemia than for non-acute myeloid leukemia. For acute leukemia, the treatment of choice was chemotherapy; for non-acute lymphatic leukemia, radiotherapy was used, followed, if required, by chemotherapy or further radiotherapy. For non-acute myeloid leukemia, the advantage of chemotherapy over radiotherapy was not established.  相似文献   

20.
This paper describes the trends in tobacco sales and smoking prevalence in the Tunisian population, estimates the consequences of smoking on mortality of this population, and discusses anti-tobacco actions: educational actions, legislative measures and price increases. Sales Data were collected from the Tunisia tobacco company. Smoking prevalence data from surveys, conducted by several institutes, and numbers of deaths by causes have been estimated from WHO for the year 1998. Tobacco sales increased from 4.96 g per adult per day in 1981, to 6.3 g, in 1993, then decreased widely. The proportion of smokers was 30% in 1996. 55% among men versus 5.6% among women. Among 17 to 24 years old young adults, the proportion of smokers was 29.2% in 1994 (50% among men versus 3.9%, among women). Mortality attributable to tobacco in Tunisia has been estimated to 6430 deaths in 1997 (5580 among men versus 850 among women). These deaths represent 22% of the total male deaths and 4% of the female ones. Anti-tobacco measures have been reinforced by the enactment of anti-tobacco law. Proportion of young smokers remaining elevated, it is expected that consequences of the tobacco addiction in Tunisia, in term of mortality, will be even heavier in the next two decades, if efficient anti-tobacco actions are not implemented.  相似文献   

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