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91.
Heritability of human cranial dimensions: comparing the evolvability of different cranial regions 总被引:1,自引:0,他引:1
Neus Martínez-Abadías Mireia Esparza Torstein Sjøvold Rolando González-José Mauro Santos Miquel Hernández 《Journal of anatomy》2009,214(1):19-35
Quantitative craniometrical traits have been successfully incorporated into population genetic methods to provide insight into human population structure. However, little is known about the degree of genetic and non-genetic influences on the phenotypic expression of functionally based traits. Many studies have assessed the heritability of craniofacial traits, but complex patterns of correlation among traits have been disregarded. This is a pitfall as the human skull is strongly integrated. Here we reconsider the evolutionary potential of craniometric traits by assessing their heritability values as well as their patterns of genetic and phenotypic correlation using a large pedigree-structured skull series from Hallstatt (Austria). The sample includes 355 complete adult skulls that have been analysed using 3D geometric morphometric techniques. Heritability estimates for 58 cranial linear distances were computed using maximum likelihood methods. These distances were assigned to the main functional and developmental regions of the skull. Results showed that the human skull has substantial amounts of genetic variation, and a t -test showed that there are no statistically significant differences among the heritabilities of facial, neurocranial and basal dimensions. However, skull evolvability is limited by complex patterns of genetic correlation. Phenotypic and genetic patterns of correlation are consistent but do not support traditional hypotheses of integration of the human shape, showing that the classification between brachy- and dolicephalic skulls is not grounded on the genetic level. Here we support previous findings in the mouse cranium and provide empirical evidence that covariation between the maximum widths of the main developmental regions of the skull is the dominant factor of integration in the human skull. 相似文献
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Núria Besalduch Marta Toms Manel M. Santaf Neus Garcia Josep Toms Maria Angel Lanuza 《The Journal of comparative neurology》2010,518(2):211-228
Protein kinase C (PKC) is essential for signal transduction in a variety of cells, including neurons and myocytes, and is involved in both acetylcholine release and muscle fiber contraction. Here, we demonstrate that the increases in synaptic activity by nerve stimulation couple PKC to transmitter release in the rat neuromuscular junction and increase the level of α, βI, and βII isoforms in the membrane when muscle contraction follows the stimulation. The phosphorylation activity of these classical PKCs also increases. It seems that the muscle has to contract in order to maintain or increase classical PKCs in the membrane. We use immunohistochemistry to show that PKCα and PKCβI were located in the nerve terminals, whereas PKCα and PKCβII were located in the postsynaptic and the Schwann cells. Stimulation and contraction do not change these cellular distributions, but our results show that the localization of classical PKC isoforms in the membrane is affected by synaptic activity. J. Comp. Neurol. 518:211–228, 2010. © 2009 Wiley‐Liss, Inc. 相似文献
95.
Carreras E Saiz A Marín P Martínez C Rovira M Villamor N Aymerich M Lozano M Fernández-Avilés F Urbano-Izpizua A Montserrat E Graus F 《Haematologica》2003,88(3):306-314
BACKGROUND AND OBJECTIVES: Autologous stem cell transplantation (ASCT) is currently being evaluated as a therapy for patients with multiple sclerosis (MS). We report the results of a phase II trial to evaluate feasibility and toxicity of CD34+ selected ASCT (CD34+/ASCT) and treatment results at one year of follow-up. DESIGN AND METHODS: Patients with advanced secondary progressive (SP) or relapsing-remitting (RR) MS and confirmed worsening of the extended disability status scale (EDSS) in the previous year despite interferon or other immunotherapies were included. Peripheral blood stem cells were obtained by leukaphereses after mobilization with cyclophosphamide (Cy) and granulocyte colony-stimulating factor (G-CSF). CD34+ selection was performed by means of an Isolex 300 or CliniMACS device. BCNU, Cy and antithymocyte globulin (ATG) were administered as conditioning regimen. RESULTS: Fifteen patients (9 SPMS and 6 RRMS) with a median EDSS of 6.0 (4.5-6.5) and a median of 3 (1-7) relapses in the previous year were included. Mobilization was unsuccessful in one patient. During mobilization, one patient had a transient neurologic deterioration. The main complication during ASCT were engraftment syndrome, which developed in three patients, CMV reactivation in one, and neurologic deterioration in two patients coinciding with high-fever related to ATG. Hematologic recovery was fast and complete in all cases. At 12 months, the EDSS had improved in three patients, worsened in two and remained stable in nine. Despite withdrawal of all immunosuppressive therapy only two patients had relapses. Magnetic resonance imaging showed disappearance of enhanced T1 lesions but oligoclonal bands persisted in the cerebrospinal fluid of all evaluated cases. INTERPRETATION AND CONCLUSIONS: CD34+/ASCT using BCNU, Cy and ATG as conditioning regimen has an acceptable toxicity and clearly reduces the progression of MS. Further follow-up is necessary to establish the real impact of this procedure on the long-term evolution of the disease. 相似文献
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The development of pneumonia requires the pathogen to reach the alveoli and the host defenses to be overwhelmed, either by microorganism virulence or by inoculums size. The endogenous sources of microorganisms are nasal carriers, sinusitis, mouth, oropharynx, gastric, or tracheal colonization, and hematogenous spread. The exogenous sources of microorganisms are biofilm of the tracheal tube, ventilator circuits, nebulizers, and humidifiers. Health care workers may also play a role in this setting. Different microorganisms can be found depending on the onset time of pneumonia and on the local pattern variation encountered between different institutions and countries. Healthy patients may be chronically colonized. A very important, unresolved issue is the definition of early and late-onset pneumonia; it still remains uncertain from the literature whether the given threshold refers to the number of days in hospital or to the number of days following intubation. Noninvasive ventilation is demonstrating that the term "ventilator-associated pneumonia" is perhaps inaccurate and should be referred to as "intubation-associated pneumonia." 相似文献
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Lara Fuentes Josep Gómez-Lara Neus Salvatella Nieves Gonzalo Felipe Hernández-Hernández Eduard Fernández-Nofrerias Ángel Sánchez-Recalde Fernando Alfonso Rafael Romaguera José Luis Ferreiro Gerard Roura Luis Teruel Montserrat Gracida Ana Lucrecia Marcano Joan-Antoni Gómez-Hospital Ángel Cequier 《Revista espa?ola de cardiología》2018,71(5):335-343
Introduction and objectives
Stent thrombosis (ST) is a life-threatening complication after stent implantation. Intravascular ultrasound is able to discern most causes of ST. The aim of this study was to compare intravascular ultrasound findings between bare-metal stents (BMS) and drug-eluting stents (DES) in patients with late (31 days to 1 year) or very late ST (> 1 year).Methods
Of 250 consecutive patients with late or very late ST in 7 Spanish institutions, 114 patients (45.5% BMS and 54.5% DES) were imaged with intravascular ultrasound. Off-line intravascular ultrasound analysis was performed to assess malapposition, underexpansion, and neoatherosclerosis.Results
The median time from stent implantation to ST was 4.0 years with BMS and 3.4 years with DES (P = .04). Isolated malapposition was similarly observed in both groups (36.5% vs 46.8%; P = .18) but was numerically lower with BMS (26.6% vs 48.0%; P = .07) in patients with very late ST. Isolated underexpansion was similarly observed in both groups (13.5% vs 11.3%; P = .47). Isolated neoatherosclerosis occurred only in patients with very late ST and was more prevalent with BMS (22.9%) than with DES (6.0%); P = .02. At 2.9 years’ follow-up, there were 0% and 6.9% cardiac deaths, respectively (P = .06) and recurrent ST occurred in 4.0% and 5.2% of patients, respectively (P = .60).Conclusions
Malapposition was the most common finding in patients with late and very late ST and is more prevalent with DES in very late ST. In contrast, neoatherosclerosis was exclusively observed in patients with very late ST and mainly with BMS.Full English text available from:www.revespcardiol.org/en 相似文献100.
Ischemic preconditioning affects interleukin release in fatty livers of rats undergoing ischemia/reperfusion 总被引:8,自引:0,他引:8
Serafín A Roselló-Catafau J Prats N Gelpí E Rodés J Peralta C 《Hepatology (Baltimore, Md.)》2004,39(3):688-698
The present study evaluates the effect of ischemic preconditioning on interleukin-1 (IL-1) and interleukin-10 (IL-10) generation following hepatic ischemia/reperfusion (I/R) in normal and steatotic livers as well as the role of nitric oxide (NO) in this process. Increased IL-1beta and IL-10 levels were observed in normal livers after I/R. Steatotic livers showed higher IL-1beta levels than normal livers, and IL-10 at control levels. The injurious role of IL-1beta and the benefits of IL-10 on hepatic I/R injury was shown with the use of IL-1 receptor antagonist (IL-1ra), anti-IL-10 polyclonal antibody against IL-10 (anti-IL-10) and exogenous IL-10. The effective dose of these treatments was different in both types of livers. Preconditioning prevented IL-1beta release and increased IL-10 generation after I/R in normal and steatotic livers. IL-1beta or anti-IL-10 pretreatments reversed the benefits of preconditioning. IL-1beta action inhibition in a preconditioned group that was pretreated with anti-IL-10 did not modify the benefits of preconditioning. In addition, anti-IL-10 pretreatment in the preconditioned group resulted in IL-1beta levels comparable to those observed after I/R. NO inhibition eliminated the benefits of preconditioning on IL-10 release, IL-1beta levels, and hepatic injury. In conclusion, preconditioning, through IL-10 overproduction, inhibits IL-1beta release and the ensuing hepatic I/R injury in normal and steatotic livers. IL-10 generation induced by preconditioning could be mediated by NO. 相似文献