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41.
Systemic lupus erythematosus is the prototype multisystem autoimmune disease. A strong genetic component of susceptibility to the disease is well established. Studies of murine models of systemic lupus erythematosus have shown complex genetic interactions that influence both susceptibility and phenotypic expression. These models strongly suggest that several defects in similar pathways, e.g. clearance of immune complexes and/or apoptotic cell debris, can all result in disease expression. Studies in humans have found linkage to several overlapping regions on chromosome 1q, although the precise susceptibility gene or genes in these regions have yet to be identified. Recent studies of candidate genes, including Fcγ receptors, IL-6, and tumour necrosis factor-α, suggest that in human disease, genetic factors do play a role in disease susceptibility and clinical phenotype. The precise gene or genes involved and the strength of their influence do, however, appear to differ considerably in different populations. 相似文献
42.
Yasmeen Siddiqui Arthy Surendran R. Russell M. Paterson Asgar Ali Khairulmazmi Ahmad 《Saudi Journal of Biological Sciences》2021,28(5):2840-2849
The rapid expansion of oil palm (OP) has led to its emergence as a commodity of strategic global importance. Palm oil is used extensively in food and as a precursor for biodiesel. The oil generates export earnings and bolsters the economy of many countries, particularly Indonesia and Malaysia. However, oil palms are prone to basal stem rot (BSR) caused by Ganoderma boninense which is the most threatening disease of OP. The current control measures for BSR management including cultural practices, mechanical and chemical treatment have not proved satisfactory. Alternative control measures to overcome the G. boninense problem are focused on the use of biological control agents and many potential bioagents were identified with little proven practical application. Planting OP varieties resistant to G. boninense could provide the ideal long-term solution to basal stem rot. The total resistance of palms to G. boninense has not yet been reported, and few examples of partial resistances have been observed. Importantly, basidiospores are now recognized as the method by which the disease is spread, and control methods require to be revaluated because of this phenomenon. Many methods developed to prevent the spread of the disease effectively are only tested at nursery levels and are only reported in national journals inhibiting the development of useful techniques globally. The initial procedures employed by the fungus to infect the OP require consideration in terms of the physiology of the growth of the fungus and its possible control. This review assesses critically the progress that has been made in BSR development and management in OP. 相似文献
43.
Background: The disparity in breast cancer mortality rates among white and black US women is widening, with higher mortality rates among black women. We apply functional time series models on age-specific breast cancer mortality rates for each group of women, and forecast their mortality curves using exponential smoothing state-space models with damping. Materials and Methods: The data were obtained from the Surveillance, Epidemiology and End Results (SEER) program of the US [1]. Mortality data were obtained from the National Centre for Health Statistics (NCHS) available on the SEER*Stat database. We use annual unadjusted breast cancer mortality rates from 1969 to 2004 in 5-year age groups (45–49, 50–54, 55–59, 60–64, 65–69, 70–74, 75–79, 80–84). Age-specific mortality curves were obtained using nonparametric smoothing methods. The curves are then decomposed using functional principal components and we fit functional time series models with four basis functions for each population separately. The curves from each population are forecast and prediction intervals are calculated. Results: Twenty-year forecasts indicate an overall decline in future breast cancer mortality rates for both groups of women. This decline appears to be steeper among white women aged 55–73 and black women aged 60–84. For black women under 55 years of age, the forecast rates are relatively stable indicating there is no significant change in future breast cancer mortality rates among young black women in the next 20 years. Conclusion: White women have smooth and consistent patterns in breast cancer mortality rates for all age-groups whereas the mortality rates for black women are much more variable. The projections suggest, for some age groups, black American women may not benefit equally from the overall decline in breast cancer mortality in the United States. 相似文献
44.
Global average temperature increase during the last century has induced species geographic range shifts and extinctions. Montane floras, in particular, are highly sensitive to climate change and mountains serve as suitable observation sites for tracing climate-induced biological response. The Himalaya constitute an important global biodiversity hotspot, yet studies on species’ response to climate change from this region are lacking. Here we use historical (1849–50) and the recent (2007–2010) data on temperature and endemic species’ elevational ranges to perform a correlative study in the two alpine valleys of Sikkim. We show that the ongoing warming in the alpine Sikkim Himalaya has transformed the plant assemblages. This study lends support to the hypothesis that changing climate is causing species distribution changes. We provide first evidence of warmer winters in the region compared to the last two centuries, with mean temperatures of the warmest and the coldest months may have increased by 0.76±0.25°C and 3.65±2°C, respectively. Warming-driven geographical range shifts were recorded in 87% of 124 endemic plant species studied in the region; upper range extensions of species have resulted in increased species richness in the upper alpine zone, compared to the 19th century. We recorded a shift of 23–998 m in species’ upper elevation limit and a mean upward displacement rate of 27.53±22.04 m/decade in the present study. We infer that the present-day plant assemblages and community structure in the Himalaya is substantially different from the last century and is, therefore, in a state of flux under the impact of warming. The continued trend of warming is likely to result in ongoing elevational range contractions and eventually, species extinctions, particularly at mountaintops. 相似文献
45.
Ebenezeri Erasto Ngowi Yi-Zhen Wang Saadullah Khattak Nazeer Hussain Khan Salma Sayed Mohamed Mahmoud Yasmeen Ahmed Saleheldin Hassan Helmy Qi-Ying Jiang Tao Li Shao-Feng Duan Xin-Ying Ji Dong-Dong Wu 《Journal of applied microbiology》2021,131(5):2131-2147
Obesity is considered as a risk factor for chronic health diseases such as heart diseases, cancer and diabetes 2. Reduced physical activities, lifestyle, poor nutritional diet and genetics are among the risk factors associated with the development of obesity. In recent years, several studies have explored the link between the gut microbiome and the progression of diseases including obesity, with the shift in microbiome abundance and composition being the main focus. The alteration of gut microbiome composition affects both nutrients metabolism and specific gene expressions, thereby disturbing body physiology. Specifically, the abundance of fibre-metabolizing microbes is associated with weight loss and that of protein and fat-metabolizing bacteria with weight gain. Various internal and external factors such as genetics, maternal obesity, mode of delivery, breastfeeding, nutrition, antibiotic use and the chemical compounds present in the environment are known to interfere with the richness of the gut microbiota (GM), thus influencing weight gain/loss and ultimately the development of obesity. However, the effectiveness of each factor in potentiating the shift in microbes’ abundance to result in significant changes that can lead to obesity is not yet clear. In this review, we will highlight the factors involved in shaping GM, their influence on obesity and possible interventions. Understanding the influence of these factors on the diversity of the GM and how to improve their effectiveness on disease conditions could be keys in the treatment of metabolic diseases. 相似文献
46.
Dongmei Zhu Wen Song Kun Yang Xiaojuan Cao Yasmeen Gul Weiming Wang 《In vitro cellular & developmental biology. Animal》2012,48(8):507-517
The genome size (C value) of eight commercially important fish species in China was measured using flow cytometry. Chicken (Gallus domesticus) erythrocytes were used as reference cells. When using propidium iodide (PI) as the fluorescent dye, genome sizes were 1.09?±?0.08, 2.75?±?0.12, 1.05?±?0.05, 1.35?±?0.11, 0.99?±?0.05, 0.90?±?0.08, 0.90?±?0.07, and 0.88?±?0.07?pg for Japanese eel (Anguilla japonica), mullet (Myxocyprinus asiaticus), yellowcheek carp (Elopichthys bambusa), blunt snout bream (Megalobrama amblycephala), yellow catfish (Pelteobagrus fulvidraco), ricefield eel (Monopterus albus), mandarin fish (Siniperca chuatsi), and snakehead (Ophicephalus argus), respectively. However, genome sizes were 1.25?±?0.00, 3.08?±?0.02, 1.25?±?0.00, 1.57?±?0.01, 0.96?±?0.01, 1.00?±?0.01, 0.91?±?0.01, and 0.89?±?0.01?pg for these fishes, respectively, when 4??, 6-diamidino-2-phenylindole (DAPI) was used as the fluorescent dye. Regardless of the dye used, the more evolutionarily advanced species had a smaller genome size than those with a lower evolutionary status. For each species, we also measured the size of erythrocytes and their nucleus and evaluated the relationships between erythrocyte size, nucleus size, chromosome number, and genome size. Genome size was positively correlated with erythrocyte nucleus size and chromosome number when using PI as the fluorescent dye, but it was only correlated with erythrocyte nucleus size when DAPI was used. 相似文献
47.
The putative anticancer alkaloids berberine, palmatine, jatrorrhizine, and sanguinarine are known to bind to nucleic acids. To develop them as potential drugs for therapeutic use, their binding affinity to functional proteins and mode of transport in the circulatory system need to be clearly understood. Towards this, many studies on their binding aspects to proteins have been reported and a considerable amount of data, mostly of biophysical nature, exists in the literature. The importance of these natural isoquinoline alkaloids and the recent literature on their interaction phenomena with functional proteins, serum albumins, hemoglobin, and lysozyme are presented in this review. 相似文献
48.
Abida Yasmeen Bushra Mirza Samia Inayatullah Naila Safdar Maryam Jamil Shawkat Ali M. Fayyaz Choudhry 《Plant Molecular Biology Reporter》2009,27(1):20-28
In this study, in planta transformation of tomato (Solanum lycopersicum L.), using fruit injection and floral dip, is reported. Agrobacterium tumefaciens strain EHA 105 containing one of three constructs, i.e., pROKIIAP1GUSint (carrying the Apetala 1 [AP1] gene), pROKIILFYGUSint (carrying the LEAFY [LFY] gene), or p35SGUSint (carrying the β-glucuronidase [GUS] gene), was used for plant transformation. For fruit injection transformation, no significant effects (p > 0.05) of the construct used were observed. The highest frequency of transformation was obtained following 48-h incubation
of tomato fruit with bacterial cells harboring either one of the three constructs; transformation frequencies of 17%, 19%,
and 21% for AP1, LFY, and GUS gene constructs, respectively, were obtained. When fruit maturity was evaluated in fruit injection experiments, mature red
fruit resulted in higher frequency of transformants than immature green fruit with 40%, 35%, and 42% for AP1, LFY, and GUS gene constructs, respectively. For floral dip transformation, a higher number of transformants was obtained when the GUS gene construct was used instead of either the AP1 or LFY gene construct, thus suggesting a possible inhibitory effect of the flowering genes used. When flowers were transformed prior
to rather than following pollination, they yielded a higher transformation frequency, 12% for the LFY construct and 23% for the GUS construct (p < 0.05), although no transformant was obtained with the AP1 gene construct. All putative GUS-positive transformants were analyzed using polymerase chain reaction and confirmed for the
presence of the transgene. Compared to control plants, transgenic plants carrying either the AP1 or LFY transgene flowered earlier and showed several different morphological characters. 相似文献
49.