Tobacco smoke is well recognized as the major etiological contributor to lung cancer, yet the relationship between tobacco smoke exposure and a specific pattern of molecular abnormalities at somatic loci is less well characterized. We analyzed 100 primary tumors from patients undergoing surgical resection of squamous cell carcinoma and adenocarcinoma of the lung for loss of heterozygosity (LOH) and homozygous deletions at two microsatellite markers in a recombinogenic region of 9p13. We describe the relationship of alterations at these markers with tumor characteristics (both clinical and molecular), patient demographics, survival, and measures of tobacco-smoke exposure. Homozygous deletions in this region occurred in 25% (21/85) and LOH in 33% (28/85) of informative tumors examined. These alterations occurred more often in tumors with intense TP53 protein staining by immunohistochemistry, suggesting that inactivation of the TP53 pathway may contribute to these LOH events. Duration of smoking was greatest in patients with the homozygous deletion, intermediate in patients with LOH, and shortest in patients whose tumor did not demonstrate loss in these markers. Unexpectedly, LOH at 9p13 was a significant predictor of improved survival in patients, while the homozygous deletion was associated with the poorest patient survival. Together, these results suggest that TP53 alteration and long-term tobacco smoke exposure may contribute to genetic alterations at 9p13, and that the mechanism and biologic consequences of allele loss reflect individual biologic differences that determine the extent of loss (LOH or homozygous deletion), such that those patients with the deletion of this region face a more aggressive and deadly disease. 相似文献
Introduction: Even though our understanding of the antiphospholipid syndrome (APS) has improved tremendously over the last decades, we are still not in a position to replace symptomatic anticoagulation by pathogenesis based causal treatments.
Areas covered: Recent years have provided further insights into pathogenetically relevant mechanisms. These include a differentiation of pathogenic subtypes of antiphospholipid antibodies (aPL), novel mechanisms modulating disease activity, for example, extracellular vesicles and microRNA, and novel players in pathogenesis, for example, neutrophils and neutrophil extracellular traps (NETs).
Expert commentary: It is evident that aPL induce a proinflammatory and procoagulant state and recent data suggest that different aPL species activate different signaling pathways which sometimes converge into a common cellular response. This implies that presence of more than one aPL species may disproportionally increase the risk for the major manifestations of APS, that is, thrombosis and fetal loss. Further delineation of the pathogenic mechanisms will hopefully provide clues to causal rather than symptomatic treatments of APS. 相似文献
The authors hypothesized that insulin and leptin, hormones that convey metabolic and energy balance status to the central nervous system (CNS), decrease the reward value of food, as assessed by conditioned place preference (CPP). CPP to high-fat diet was blocked in ad-lib fed rats given intraventricular insulin or leptin throughout training and test or acutely before the test. Insulin or leptin given only during the training period did not block CPP. Thus, elevated insulin and leptin do not prevent learning a food's reward value, but instead block its retrieval. Food-restricted rats receiving cerebrospinal fluid, insulin, or leptin had comparable CPPs. Results indicate that the CNS roles of insulin and leptin may include processes involving memory and reward. 相似文献
Summary In 60-day (group A) and 90-day (group B) old rabbits a standardized osteochondral graft was taken from the distal articular surface of the femur and replanted immediately. Five animals in each group were observed at 9 different times between 3 days and 6 months. On histological and autoradiographic (35S-sulphate) examination the following were found: In group A there was no 35S uptake in the deep layers of the articular cartilage between 3 days and 1 week; in most cases there was normal articular cartilage in the transplants at 2 weeks to 6 months. In group B later changes (3 weeks—6 months), affecting the greater part of the articular cartilage, were observed. These changes appeared to be irreversible and were found in about 1/3 of the cases. The other 2/3 showed completely normal articular cartilage.Fluorescence-microscopic (after tetracycline administration), microradiographic and microangiographic (Indian ink) studies revealed the following: Revascularization of the subchondral bone took place after 3–5 days. The ossification process in the subchondral area was restored within 5–7 days. The osseous part of the transplants healed by primary bone union within 1–2 weeks. The revascularization took place more rapidly in group A.At the longest observation times (8 weeks and 6 months) in both groups slight flattening of the transplant area was seen, probably as a result of slightly retarded growth of the bone within the transplant.Supported by grants from the Swedish Medical Research Council, Project No. 17 X-138-08 A. 相似文献
Major depression is conditionally linked to a polymorphism of the human serotonin transporter gene (SLC6A4). During the presentation of aversive, but not pleasant, pictures, healthy carriers of the SLC6A4 short (s) allele showed stronger activation of the amygdala on functional magnetic resonance imaging. s carriers also showed greater coupling between the amygdala and the ventromedial prefrontal cortex, which may contribute to the abnormally high activity in the amygdala and medial prefrontal cortex seen in major depression. 相似文献
With the use of various techniques an attempt was made to characterize the aggregates that exist in micellar surfactant solutions of salts of the perfluornonanoic acid. The cmc values of the investigated systems were determined by conductivity and surface tension measurements. Conclusions about the shape of the micellar aggregates were drawn from rheologic and electric birefringence measurements. For the lithium, the ammonium and the tetramethylammonium surfactants the existence of normal micelles with spherical shape and with all surfactant ions lying at the micellar surface was found. The perfluornonanoate surfactants with the ammonium counterions that are partially substituted by alkyl groups showed in all investigations a behaviour that was different from the normal case. It was postulated that these solutions contain emulsion-droplet-like giant micelles with the surfactant ions and counterions solubilized as ion pairs in the interior of the micelles. Some of these giant micelles do not have spherical shape; these solutions showed electric birefringence. In most cases the giant micelles disappeared at higher temperatures. Only normal small micelles with spherical symmetry could then be detected and the measured values were again in the range for values of normal C8-perfluordetergents. On the basis of the investigated systems reasons and models for the formation of giant micelles are discussed. 相似文献
Zusammenfassung Es wird ein neues Verfahren zur automatischen Untersuchung von Enzymkinetiken angegeben. Die Umsatzgeschwindigkeit einer Enzymreaktion in Abhängigkeit von jeweils einer veränderlichen Größe wird hierbei am durchlaufenden Reaktionsgemisch kontinuierlich gemessen und registriert. Unabhängige Veränderliche kann eine Konzentration (z. B. Substrat-, Coenzym-, Wasserstoffionenkonzentration) oder die Temperatur sein. Am Beispiel der Ermittlung einer Aktivitäts-pS-Kurve (Koordinaten:v=Umsatzgeschwindigkeit;pS=negativer Logarithmus der Substratkonzentration) wird das Verfahren im Einzelnen beschrieben. Unsere Methode eignet sich bisher zur Untersuchung von Enzymen, deren Umsatz durch Messung der Lichtabsorption erfaßbar ist. Als Beispiel werden Aktivitäts-pS-Kurven von Lactatdehydrogenase aus menschlichem Herzmuskel- und Leberhomogenisat sowie von Kaninchenmuskel-LDH gezeigt und die ermittelten Michaeliskonstanten angegeben. 相似文献
Even now rare human cytomegalovirus (hCMV) reactivation is still a life-threatening complication after solid organ transplantation. Although PCR techniques are regarded as the most sensitive detection methods for hCMV, their accuracy and reproducibility are limited. This is a major disadvantage with quantitative PCR assays, which are thought to provide valuable information about hCMV latency or active viral replication in transplant patients. To enhance the diagnostic safety of quantitative hCMV PCR, we developed a duplex real-time fluorescence PCR that is capable of quantifying hCMV DNA and beta-actin DNA as internal control simultaneously within one reaction. By the use of 6-carboxyfluorescein and hexa-chloro-6-carboxyfluorescein as reporter fluorophores and 4-(4'-dimethylamino-phenylazo) benzoic acid as dark quencher dye, hCMV DNA and beta-actin DNA could be quantified in parallel in a wide linear range from 10(1) to 10(7) copies, each. To test the clinical applicability of this approach, we investigated hCMV DNA kinetics in peripheral leukocytes of three hCMV antigen-positive and four antigen-negative patients after liver transplantation, as assessed by intracellular hCMV pp65 alkaline phosphate-anti-alkaline phosphate (APAAP) complex. While all APAAP-negative individuals remained PCR negative, kinetics of HCMV DNA in leukocyte DNA samples of APAAP-positive patients correlated closely with hCMV antigen tests. Here, comparison of separate and simultaneous target quantitation revealed identical results. It is of interest that, while single hCMV antigen positivity is commonly not regarded as a reliable parameter of viral reactivation, in our study a viral load greater than 10(4) copies/2x10(5) beta-actin DNA copies clearly indicated a subsequent increase in APAAP-positive leukocytes. We conclude that with the presented method the reliability of hCMV quantitation via real-time PCR can be substantially increased and may be used to monitor hCMV kinetics in vivo. 相似文献