27 research outputs found
Multicenter Study of 19 Aortopulmonary Window parathyroid Tumors : The callenge of Embryologic origin
peer reviewedBackground Ectopic abnormal parathyroid glands are relatively
common in the superior mediastinum but are rarely
situated in the aortopulmonary window (APW). The embryological
origin of these abnormal parathyroid glands is controversial.
The purpose of this investigation was to investigate
the embryological origin and the surgical management of
abnormal parathyroid glands situated in the APW.
Methods The databases of patients operated on for primary,
secondary, and tertiary hyperparathyroidism at eight
European medical centers with a special interest in endocrine
surgery were reviewed to identify those with APW adenomas.
Demographic features, localization procedures, and
perioperative and pathology findings were documented. The
embryological origin was determined based on the number
and position of identified parathyroid glands.
Results Nineteen (0.24%) APW parathyroid tumors were
identified in 7,869 patients who underwent an operation for
hyperparathyroidism (HPT) and 181 patients (2.3%) with
mediastinal abnormal parathyroid glands. Ten patients had
primary, eight had secondary, and one had tertiary HPT.
Sixteen patients had undergone previous unsuccessful cervical
exploration. In three patients, an APW adenoma was
suspected by preoperative localization studies and was cured
at the initial operation. Sixteen patients had persistent HPTof
whom 15 were reoperated, resulting in 6 failures. Evaluation
of 17 patients who had bilateral neck exploration allowed us
to determine the most probable origin of the APW parathyroid
tumors: 12 were supernumerary, 4 appeared to originate
from a superior, and 1 from an inferior gland.
Conclusions Abnormal parathyroid glands situated in the
APW are rare and usually identified after an unsuccessful
cervical exploration. Preoperative imaging of the mediastinum
and neck are essential. The origin of these ectopically
situated tumors is probably, as suggested by our data, from a
supernumerary fifth parathyroid gland or from abnormal
migration of a superior parathyroid gland during the
embryologic development
Enabling Model Testing of Cyber-Physical Systems
Applying traditional testing techniques to Cyber-Physical Systems (CPS) is challenging due to the deep intertwining of software and hardware, and the complex, continuous interactions between the system and its environment. To alleviate these challenges we propose to conduct testing at early stages and over executable models of the system and its environment. Model testing of CPSs is however not without difficulties. The complexity and heterogeneity of CPSs renders necessary the combination of different modeling formalisms to build faithful models of their different components. The execution of CPS models thus requires an execution framework supporting the co-simulation of different types of models, including models of the software (e.g., SysML), hardware (e.g., SysML or Simulink), and physical environment (e.g., Simulink). Furthermore, to enable testing in realistic conditions, the co-simulation process must be (1) fast, so that thousands of simulations can be conducted in practical time, (2) controllable, to precisely emulate the expected runtime behavior of the system and, (3) observable, by producing simulation data enabling the detection of failures. To tackle these challenges, we propose a SysML-based modeling methodology for model testing of CPSs, and an efficient SysML-Simulink co-simulation framework. Our approach was validated on a case study from the satellite domain
Adult rat liver cells transdifferentiated with lentiviral IPF1 vectors reverse diabetes in mice: an ex vivo gene therapy approach
Therapeutic Potential of HDL in Cardioprotection and Tissue Repair
Epidemiological studies support a strong association between high-density lipoprotein (HDL) cholesterol levels and heart failure incidence. Experimental evidence from different angles supports the view that low HDL is unlikely an innocent bystander in the development of heart failure. HDL exerts direct cardioprotective effects, which are mediated via its interactions with the myocardium and more specifically with cardiomyocytes. HDL may improve cardiac function in several ways. Firstly, HDL may protect the heart against ischaemia/reperfusion injury resulting in a reduction of infarct size and thus in myocardial salvage. Secondly, HDL can improve cardiac function in the absence of ischaemic heart disease as illustrated by beneficial effects conferred by these lipoproteins in diabetic cardiomyopathy. Thirdly, HDL may improve cardiac function by reducing infarct expansion and by attenuating ventricular remodelling post-myocardial infarction. These different mechanisms are substantiated by in vitro, ex vivo, and in vivo intervention studies that applied treatment with native HDL, treatment with reconstituted HDL, or human apo A-I gene transfer. The effect of human apo A-I gene transfer on infarct expansion and ventricular remodelling post-myocardial infarction illustrates the beneficial effects of HDL on tissue repair. The role of HDL in tissue repair is further underpinned by the potent effects of these lipoproteins on endothelial progenitor cell number, function, and incorporation, which may in particular be relevant under conditions of high endothelial cell turnover. Furthermore, topical HDL therapy enhances cutaneous wound healing in different models. In conclusion, the development of HDL-targeted interventions in these strategically chosen therapeutic areas is supported by a strong clinical rationale and significant preclinical data.status: publishe
Transgenic mice over expressing Glial Derived Neurotrophic Factor have increased beta cell mass
Diabetic rats with high levels of endogenous dopamine do not show retinal vascular pathology
PurposeLimited research exists on the time course of long-term retinal and cerebral deficits in diabetic rodents. Previously, we examined short term (4–8 weeks) deficits in the Goto-Kakizaki (GK) rat model of Type II diabetes. Here, we investigated the long-term (1–8 months) temporal appearance of functional deficits (retinal, cognitive, and motor), retinal vascular pathology, and retinal dopamine levels in the GK rat.MethodsIn GK rats and Wistar controls, retinal neuronal function (electroretinogram), cognitive function (Y-maze), and motor function (rotarod) were measured at 1, 2, 4, 6, and 8 months of age. In addition, we evaluated retinal vascular function (functional hyperemia) and glucose and insulin tolerance. Retinas from rats euthanized at ≥8 months were assessed for vascular pathology. Dopamine and DOPAC levels were measured via HPLC in retinas from rats euthanized at 1, 2, 8, and 12 months.ResultsGoto-Kakizaki rats exhibited significant glucose intolerance beginning at 4 weeks and worsening over time (p &lt; 0.001). GK rats also showed significant delays in flicker and oscillatory potential implicit times (p &lt; 0.05 to p &lt; 0.001) beginning at 1 month. Cognitive deficits were observed beginning at 6 months (p &lt; 0.05), but no motor deficits. GK rats showed no deficits in functional hyperemia and no increase in acellular retinal capillaries. Dopamine levels were twice as high in GK vs. Wistar retinas at 1, 2, 8, and 12 months (p &lt; 0.001).ConclusionAs shown previously, retinal deficits were detectable prior to cognitive deficits in GK rats. While retinal neuronal function was compromised, retinal vascular pathology was not observed, even at 12+ months. High endogenous levels of dopamine in the GK rat may be acting as an anti-angiogenic and providing protection against vascular pathology.</jats:sec
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Diabetic rats with high levels of endogenous dopamine do not show retinal vascular pathology
PurposeLimited research exists on the time course of long-term retinal and cerebral deficits in diabetic rodents. Previously, we examined short term (4-8 weeks) deficits in the Goto-Kakizaki (GK) rat model of Type II diabetes. Here, we investigated the long-term (1-8 months) temporal appearance of functional deficits (retinal, cognitive, and motor), retinal vascular pathology, and retinal dopamine levels in the GK rat.MethodsIn GK rats and Wistar controls, retinal neuronal function (electroretinogram), cognitive function (Y-maze), and motor function (rotarod) were measured at 1, 2, 4, 6, and 8 months of age. In addition, we evaluated retinal vascular function (functional hyperemia) and glucose and insulin tolerance. Retinas from rats euthanized at ≥8 months were assessed for vascular pathology. Dopamine and DOPAC levels were measured via HPLC in retinas from rats euthanized at 1, 2, 8, and 12 months.ResultsGoto-Kakizaki rats exhibited significant glucose intolerance beginning at 4 weeks and worsening over time (p < 0.001). GK rats also showed significant delays in flicker and oscillatory potential implicit times (p < 0.05 to p < 0.001) beginning at 1 month. Cognitive deficits were observed beginning at 6 months (p < 0.05), but no motor deficits. GK rats showed no deficits in functional hyperemia and no increase in acellular retinal capillaries. Dopamine levels were twice as high in GK vs. Wistar retinas at 1, 2, 8, and 12 months (p < 0.001).ConclusionAs shown previously, retinal deficits were detectable prior to cognitive deficits in GK rats. While retinal neuronal function was compromised, retinal vascular pathology was not observed, even at 12+ months. High endogenous levels of dopamine in the GK rat may be acting as an anti-angiogenic and providing protection against vascular pathology
