A possible two-photon effect in vitro using a focused laser beam

A probable two-photon effect is described as a result of focusing an intense pulsed laser beam onto chromosomes of living cells. The effect was suggested after the derivation of a two-photon action spectrum and the demonstration of a lack of reciprocity.     

Characteristics of highly physically active smokers in a population of young adult military recruits

A substantial number of cigarette smokers are thought to engage in regular exercise. It is unclear why individuals who engage in a health-promoting activity such as exercising would simultaneously engage in a health-damaging behavior like smoking. Two possibilities are that (1) exercise serves as a "harm reduction" strategy to lessen the negative effects of smoking, or (2) that among weight conscious individuals, exercise and smoking are both used as weight control strategies. To examine these issues, smoking status, physical activity level, weight concerns, and several additional health behaviors and attitudes were assessed by questionnaire in a population of United States Air Force recruits (n=32,144). Multiple logistic regression analyses were used to compare characteristics of highly physically active smokers with both highly physically active never-smokers, and less active smokers. A substantial proportion of smokers reported being highly physically active (15.8%), although this proportion was significantly higher for never-smokers (22.7%). Active smokers were similar to active never-smokers across several health behaviors and attitudes, including diet, seatbelt use, and attitudes toward illegal drugs and condom use. Compared to less active smokers, active smokers consumed more fruits and vegetables, worried less about their weight, were less nicotine dependent, and had greater previous success at quitting smoking. These findings indicate that a substantial proportion of highly physically active young adults are regular cigarette smokers. Based on findings regarding general health behaviors and smoking history, this group may be particularly amenable to smoking cessation efforts.     

Low density lipoprotein phosphorylates the focal adhesion-associated kinase p125(FAK) in human platelets independent of integrin alphaIIb beta3

Low density lipoprotein (LDL) is known to sensitize platelets to agonists via integrin mediated outside-in signaling (Hackeng, C. M., Huigsloot, M., Pladet, M. W., Nieuwenhuis, H. K., Rijn, H. J. M. v., and Akkerman, J. W. N. (1999) Arterioscler. Thromb. Vasc. Biol., in press). As outside in signaling is associated with phosphorylation of p125(FAK), the effect of LDL on p125(FAK) phosphorylation in platelets was investigated. LDL induced p125(FAK) phosphorylation in a dose- and time- dependent manner. The phosphorylation was independent of ligand binding to integrin alphaIIbbeta3 and aggregation, such in contrast to alpha-thrombin-induced p125(FAK) phosphorylation, that critically depended on platelet aggregation. Platelets from patients with Glanzmann's thrombastenia showed the same LDL- induced phos- phorylation of p125(FAK) as control platelets, whereas alpha-thrombin completely failed to phosphorylate the kinase in the patients platelets. LDL signaling to p125(FAK) was independent of integrin alpha2 beta1, the FcgammaRII receptor, and the lysophosphatidic acid receptor and not affected by inhibitors of cyclooxygenase, protein kinase C, ERK1/2 or p38(MAPK). Phosphorylation of p125(FAK) by LDL was strongly inhibited by cyclic AMP. These observations indicate that LDL is a unique platelet agonist, as it phosphorylates p125(FAK) in platelet suspensions, under unstirred conditions and independent of integrin alphaIIb beta3.     

Theoretical prediction of the hemodynamic performance of slow resorbing polyester protein impregnated arterial prostheses after implantation: a plea for fast resorption of the coating

OBJECTIVE: Although age-related mortality after intensive care unit (ICU) admission has been studied, functional recovery for different age groups following ICU admission is not well characterized. We hypothesized that compared with younger age groups, fewer patients older than age 65 admitted to an ICU would regain their full prehospitalization functional ability and that their recovery would be slower than that of younger patients. DESIGN: A prospective observational cohort study with convenience sampling. SETTING: Intensive care units of an urban university-affiliated Veterans Administration Medical Center. PARTICIPANTS: A total of 222 patients during the first 72 hours after entry to a medical or surgical ICU at the Denver Veteran's Administration Medical Center between September 1991 and July 1992. MEASUREMENTS: We collected baseline data on patient demographics and on the severity of acute illness using the Acute Physiology and Chronic Health Evaluation (APACHE II), Acute Physiology Score (APS), and functional status (highest level of physical activity level 1 month before admission). We recorded survival and patient-perceived global functional status at 6 weeks and 6 months after admission. Post-ICU function was adjusted for baseline function, age, APACHE II, and APS using multiple regression. RESULTS: Average patient age was 62+/-.74 years (mean +/- SEM). Fifty-two percent of the entire cohort returned to baseline function at 6 months. Although baseline function was better for younger people, there was no difference in recovery at 6 weeks in older compared with younger patients. Most functional recovery occurred by 6 weeks, with maintenance of this recovery at 6 months. Baseline function was the major determinant of both 6 week recovery (P < .001) and 6 month recovery (P = .002), whereas APACHE II was not (P = .3). Age predicted recovery significantly (P = .04) at 6 months but not at 6 weeks (P = .26). APACHE II (P < .001) and baseline function (P = .03) predicted mortality. CONCLUSIONS: Older people had worse functional ability at ICU admission, but the proportion of older people who recovered and their rate of recovery was the same as for younger people. Baseline functional status, rather than abnormal physiologic status (as measured by APACHE II) on admission, was the major determinant of recovery, whereas APACHE II was the main correlate of mortality. Together, baseline function and physiologic status provide valuable complementary information for clinically relevant outcomes following an ICU admission.