Protocols and video articles authored by guoyi gao anoxia adalah

Holistic and network analysis of meningioma pathogenesis and malignancy

BioFactors (oxford, england).

2006 |

Pubmed ID: 17473381 meningiomas, which originate from arachnoid cells and constitute the largest subgroup of all intracranial tumors, are generally benign, yet have the capacity to progress into a higher histological grade of malignancy associated with an increase in biological aggressivity and/or capacity to recur. To elucidate meningioma pathogenesis and malignancy, we applied a holistic and network approach analyzing cdna and tissue microarray results. A potential pathway leading to meningioma angiogenesis, apoptosis and proliferation was evidenced as well as a regulatory network of the biomarkers including ki-67, AR, CD34, P53, c-MYC, etc.Anoxia adalah

which might support clinical research. In this potential pathway, ITGB1 could be the most important superoncogene playing a vital role in apoptosis and proliferation, while FOXO3A, MDM4 and MT3 are important to the malignancy process. Some genes are first reported that could explain why radiation induces meningioma and why more female than male patients are affected. Further, we present the hypothesis that HIV-tat protein might have a close relationship with meningioma pathogenesis and malignancy.

The adverse pial arteriolar and axonal consequences of traumatic brain injury complicated by hypoxia and their therapeutic modulation with hypothermia in rat

Journal of cerebral blood flow and metabolism : official journal of the international society of cerebral blood flow and metabolism.Anoxia adalah

Mar, 2010 |

Pubmed ID: 19904286 this study examined the effect of posttraumatic hypoxia on cerebral vascular responsivity and axonal damage, while also exploring hypothermia’s potential to attenuate these responses. Rats were subjected to impact acceleration injury (IAI) and equipped with cranial windows to assess vascular reactivity to topical acetylcholine, with postmortem analyses using antibodies to amyloid precursor protein to assess axonal damage. Animals were subjected to hypoxia alone, IAI and hypoxia, IAI and hypoxia before induction of moderate hypothermia (33 degrees C), IAI and hypoxia induced during hypothermic intervention, and IAI and hypoxia initiated after hypothermia. Hypoxia alone had no impact on vascular reactivity or axonal damage.Anoxia adalah acceleration injury and posttraumatic hypoxia resulted in dramatic axonal damage and altered vascular reactivity. When IAI and hypoxia were followed by hypothermic intervention, no axonal or vascular protection ensued. However, when IAI was followed by hypoxia induced during hypothermia, axonal and vascular protection followed. When this same hypoxic insult followed the use of hypothermia, no benefit ensued. These studies show that early hypoxia and delayed hypoxia exert damaging axonal and vascular consequences. Although this damage is attenuated by hypothermia, this follows only when hypoxia occurs during hypothermia, with no benefit found if the hypoxic insult proceeds or follows hypothermia.Anoxia adalah

Sequencing of 50 human exomes reveals adaptation to high altitude

Science (new york, N.Y.).

Jul, 2010 |

Pubmed ID: 20595611 residents of the tibetan plateau show heritable adaptations to extreme altitude. We sequenced 50 exomes of ethnic tibetans, encompassing coding sequences of 92% of human genes, with an average coverage of 18x per individual. Genes showing population-specific allele frequency changes, which represent strong candidates for altitude adaptation, were identified. The strongest signal of natural selection came from endothelial per-arnt-sim (PAS) domain protein 1 (EPAS1), a transcription factor involved in response to hypoxia. One single-nucleotide polymorphism (SNP) at EPAS1 shows a 78% frequency difference between tibetan and han samples, representing the fastest allele frequency change observed at any human gene to date.Anoxia adalah this SNP’s association with erythrocyte abundance supports the role of EPAS1 in adaptation to hypoxia. Thus, a population genomic survey has revealed a functionally important locus in genetic adaptation to high altitude.

Combinational therapy using hypothermia and the immunophilin ligand FK506 to target altered pial arteriolar reactivity, axonal damage, and blood-brain barrier dysfunction after traumatic brain injury in rat

Journal of cerebral blood flow and metabolism : official journal of the international society of cerebral blood flow and metabolism.

Apr, 2011 |

Pubmed ID: 21157473 this study evaluated the utility of combinational therapy, coupling delayed posttraumatic hypothermia with delayed FK506 administration, on altered cerebral vascular reactivity, axonal injury, and blood-brain barrier (BBB) disruption seen following traumatic brain injury (TBI).Anoxia adalah animals were injured, subjected to various combinations of hypothermic/FK506 intervention, and equipped with cranial windows to assess pial vascular reactivity to acetylcholine. Animals were then processed with antibodies to the amyloid precursor protein and immunoglobulin G to assess axonal injury and BBB disruption, respectively. Animals were assigned to five groups: (1) sham injury plus delayed FK506, (2) TBI, (3) TBI plus delayed hypothermia, (4) TBI plus delayed FK506, and (5) TBI plus delayed hypothermia with FK506. Sham injury plus FK506 had no impact on vascular reactivity, axonal injury, or BBB disruption. Traumatic brain injury induced dramatic axonal injury and altered pial vascular reactivity, while triggering local BBB disruption.Anoxia adalah delayed hypothermia or FK506 after TBI provided limited protection. However, TBI with combinational therapy achieved significantly enhanced vascular and axonal protection, with no BBB protection. This study shows the benefits of combinational therapy, using posttraumatic hypothermia with FK506 to attenuate important features of TBI. This suggests that hypothermia not only protects but also extends the therapeutic window for improved FK506 efficacy.

Transcriptome and network changes in climbers at extreme altitudes

PloS one.

2012 |

Pubmed ID: 22393366 extreme altitude can induce a range of cellular and systemic responses. Although it is known that hypoxia underlies the major changes and that the physiological responses include hemodynamic changes and erythropoiesis, the molecular mechanisms and signaling pathways mediating such changes are largely unknown.Anoxia adalah to obtain a more complete picture of the transcriptional regulatory landscape and networks involved in extreme altitude response, we followed four climbers on an expedition up mount xixiabangma (8,012 m), and collected blood samples at four stages during the climb for mrna and mirna expression assays. By analyzing dynamic changes of gene networks in response to extreme altitudes, we uncovered a highly modular network with 7 modules of various functions that changed in response to extreme altitudes. The erythrocyte differentiation module is the most prominently up-regulated, reflecting increased erythrocyte differentiation from hematopoietic stem cells, probably at the expense of differentiation into other cell lineages.Anoxia adalah these changes are accompanied by coordinated down-regulation of general translation. Network topology and flow analyses also uncovered regulators known to modulate hypoxia responses and erythrocyte development, as well as unknown regulators, such as the OCT4 gene, an important regulator in stem cells and assumed to only function in stem cells. We predicted computationally and validated experimentally that increased OCT4 expression at extreme altitude can directly elevate the expression of hemoglobin genes. Our approach established a new framework for analyzing the transcriptional regulatory network from a very limited number of samples.

Acute traumatic brain injury: is current management evidence based?Anoxia adalah an empirical analysis of systematic reviews

Journal of neurotrauma.

Apr, 2013 |

Pubmed ID: 23151044 traumatic brain injury (TBI) is a major health and socioeconomic problem worldwide with a high rate of death and long-term disability. Previous studies have summarized evidence from large-scale randomized trials, finding no intervention showing convincing efficacy for acute TBI management. The present empirical study set out to assess another crucial component of evidence base-systematic review, which contributes a lot to evidence-based health care, in terms of clinical issues, methodological aspects, and implication for practice and research. A total of 44 systematic reviews pertaining to therapeutic interventions for acute TBI were identified through electronic database searching, clinical guideline retrieval, and expert consultation, of which 21 were published in cochrane library and 23 in peer-reviewed journals.Anoxia adalah their methodological quality was generally satisfactory, with the median overview quality assessment questionnaire score of 5.5 (interquartile range 2-7). Cochrane reviews are of better quality than regular journal reviews. Twenty-nine high-quality reviews provided no conclusive evidence for the investigated 22 interventions except for an adverse effect of corticosteroids. Less than one-third of the component trials were reported with adequate allocation concealment. Additionally other methodological flaws in design-for example, ignoring heterogeneity among the TBI population-also contributed to the failure of past clinical research. Based on the above findings, evidence from both systematic reviews and clinical trials does not fully support current management of acute TBI.Anoxia adalah translating from laboratory success to clinical effect remains an unique challenge. Accordingly it may be the time to rethink the way in future practice and clinical research in TBI.

Altitude adaptation in tibetans caused by introgression of denisovan-like DNA


Aug, 2014 |

Pubmed ID: 25043035 as modern humans migrated out of africa, they encountered many new environmental conditions, including greater temperature extremes, different pathogens and higher altitudes. These diverse environments are likely to have acted as agents of natural selection and to have led to local adaptations. One of the most celebrated examples in humans is the adaptation of tibetans to the hypoxic environment of the high-altitude tibetan plateau.Anoxia adalah A hypoxia pathway gene, EPAS1, was previously identified as having the most extreme signature of positive selection in tibetans, and was shown to be associated with differences in haemoglobin concentration at high altitude. Re-sequencing the region around EPAS1 in 40 tibetan and 40 han individuals, we find that this gene has a highly unusual haplotype structure that can only be convincingly explained by introgression of DNA from denisovan or denisovan-related individuals into humans. Scanning a larger set of worldwide populations, we find that the selected haplotype is only found in denisovans and in tibetans, and at very low frequency among han chinese. Furthermore, the length of the haplotype, and the fact that it is not found in any other populations, makes it unlikely that the haplotype sharing between tibetans and denisovans was caused by incomplete ancestral lineage sorting rather than introgression.Anoxia adalah our findings illustrate that admixture with other hominin species has provided genetic variation that helped humans to adapt to new environments.

Right median nerve electrical stimulation for acute traumatic coma patients

Journal of neurotrauma.

Oct, 2015 |

Pubmed ID: 25664378 the right median nerve as a peripheral portal to the central nervous system can be electrically stimulated to help coma arousal after traumatic brain injury (TBI). The present study set out to examine the efficacy and safety of right median nerve electrical stimulation (RMNS) in a cohort of 437 comatose patients after severe TBI from august 2005 to december 2011. The patients were enrolled 2 weeks after their injury and assigned to the RMNS group (n=221) receiving electrical stimulation for 2 weeks or the control group (n = 216) treated by standard management according to the date of birth in the month.Anoxia adalah the baseline data were similar. After the 2-week treatment, the RMNS-treated patients demonstrated a more rapid increase of the mean glasgow coma score, although statistical significance was not reached (8.43 ± 4.98 vs. 7.47 ± 5.37, p = 0.0532). The follow-up data at 6-month post-injury showed a significantly higher proportion of patients who regained consciousness (59.8% vs. 46.2%, p = 0.0073). There was a lower proportion of vegetative persons in the RMNS group than in the control group (17.6% vs. 22.0%, p = 0.0012). For persons regaining consciousness, the functional independence measurement (FIM) score was higher among the RMNS group patients (91.45 ± 8.65 vs. 76.23 ± 11.02, p 0.001). There were no unique complications associated with the RMNS treatment.Anoxia adalah the current study, although with some limitations, showed that RMNS may serve as an easy, effective, and noninvasive technique to promote the recovery of traumatic coma in the early phase.