Psychophysiological correlates of infant temperament: stability of behavior and autonomic patterning from 5 to 18 months

The stability of infant temperament and autonomic patterning (heart period and cardiac vagal tone) was examined longitudinally when infants were 5, 10, and 18 months of age. Behavioral measures of reactivity and regulation to frustration tasks, and maternal perceptions of infant temperament were obtained at each age along with baseline measures of cardiac activity. No stability was found from 5 to 10 months while some stability of behavior and autonomic patterning was identified from 10 to 18 months, with the exception of negative reactivity. High levels of cardiac vagal tone (V) were associated with negative reactivity at 18 months. When examining groups based on degrees of reactivity and regulation, we found infants who responded negatively to frustration but who also displayed more regulatory behavior to have higher V.     

Fast tracking in cardiac surgery: implications for practice

Even though economic incentives might have been the impetus for its revival, fast tracking offers numerous other benefits, not the least of which is improved patient care. However, its benefits can be realized only through specific perioperative management, including preoperative assessment, identification and selection of appropriate candidates, optimal intra- and postoperative management and interdisciplinary discharge planning. Through interdisciplinary collaboration, the maximum benefits of fast tracking can be reaped by both the patient and the healthcare team.     

Effect of a coffee lipid (cafestol) on cholesterol metabolism in human skin fibroblasts

The receptor (R) for epidermal growth factor (EGF) is expressed at high levels on human breast cancer cells and associates with ErbB2, ErbB3, and Src proto-oncogene family protein tyrosine kinases (PTKs) to form membrane-associated PTK complexes with pivotal signaling functions. Recombinant human EGF was conjugated to the soybean-derived PTK inhibitor genistein (Gen) to construct an EGF-R-directed cytotoxic agent with PTK inhibitory activity. The EGF-Gen conjugate was capable of binding to and entering EGF-R-positive MDA-MB-231 and BT-20 breast cancer cells (but not EGF-R-negative NALM-6 or HL-60 leukemia cells) via its EGF moiety, and it effectively competed with unconjugated EGF for target EGF-R molecules in ligand binding assays. EGF-Gen inhibited the EGF-R tyrosine kinase in breast cancer cells at nanomolar concentrations, whereas the IC50 for unconjugated Gen was >10 microM. Notably, EGF-Gen triggered a rapid apoptotic cell death in MDA-MB-231 as well as BT-20 breast cancer cells at nanomolar concentrations. The EGF-Gen-induced apoptosis was EGF-R-specific because cells treated with the control granulocyte-colony stimulating factor-Gen conjugate did not become apoptotic. Apoptosis was dependent both on the PTK inhibitory function of Gen and the targeting function of EGF, because cells treated with unconjugated Gen plus unconjugated EGF did not undergo apoptosis. The IC50s of EGF-Gen versus unconjugated Gen against MDA-MB-231 and BT-20 cells in clonogenic assays were 30 +/- 3 nM versus 120 +/- 18 microM (P < 0.001) and 30 +/- 10 nM versus 112 +/- 17 microM (P < 0.001), respectively. Thus, the EGF-Gen conjugate is a >100-fold more potent inhibitor of EGF-R tyrosine kinase activity in intact breast cancer cells than unconjugated Gen and a >100-fold more potent cytotoxic agent against EGF-R+ human breast cancer cells than unconjugated Gen. Taken together, these results indicate that the EGF-R-associated PTK complexes have vital antiapoptotic functions in human breast cancer cells and may therefore be used as therapeutic targets.     

Repeatability of the Petrifilm HEC test and agreement with a hydrophobic grid membrane filtration method for the enumeration of Escherichia coli O157:H7 on beef carcasses

The review highlights recent advances in our understanding of basic mechanisms of reperfusion injury after warm hepatic ischemia. Kupffer cells play a central role as the initial cytotoxic cell type and as a source of many proinflammatory mediators. Subsequently, neutrophils are activated and recruited into the liver. Factors and conditions are outlined that determine whether neutrophils undergo apoptosis without causing damage or migrate out of the sinusoids and attack parenchymal cells. In addition to the inevitable inflammatory response during reperfusion, microcirculatory perfusion failure, due to an imbalance between the actions of vasodilators and vasoconstrictors, also has a serious impact on reperfusion injury. A better understanding of the basic pathophysiology will reveal potential targets for therapeutic interventions and will show us how to avoid risk factors that may aggravate reperfusion injury.     

Photoreceptor loss in age-related macular degeneration

PURPOSE: The authors showed previously that parafoveal rods, but not cones, decrease during the course of adulthood in donor eyes that were screened to exclude the grossly visible macular drusen and pigmentary disturbances typical of age-related macular degeneration (AMD). Because AMD begins in the parafovea, this selective loss of rods actually may be subclinical AMD not yet visible in the fundus. If so, AMD must have a predilection for rods over cones. The authors tested this hypothesis by determining the relative numbers of cones and rods in donor eyes with mid-to late-stage AMD and in age-matched controls. METHODS: Thirteen eyes (from seven donors) with grossly visible macular drusen and pigmentary disturbances were either wholemounted for photoreceptor counts or sectioned through the fovea for histopathology and carbonic anhydrase histochemistry to label red-green cones. Eyes were assigned to AMD or control groups on the basis of histopathology and clinical history. RESULTS: Five nonexudative AMD (NE-AMD) eyes from three donors showed sparing of foveal cones and loss of rods and cones in the parafovea. In two donors, rod loss exceeded cone loss at most parafoveal locations, and in one donor, rod density was normal and cone density was reduced. In eight exudative AMD (EX-AMD) eyes from five donors, photoreceptors surviving along the margins of and overlying disciform scars were largely cones. CONCLUSIONS: Photoreceptors are lost in NE-AMD as well as in the more severe exudative form, consistent with functional and clinical studies. The authors propose that rods die in older eyes without evidence of overt retinal pigment epithelial disease. In persons susceptible to AMD, the retinal pigment epithelium becomes dysfunctional. Secondarily, rod loss continues and cones begin to degenerate. Eventually, only degenerate cones remain; ultimately, all photoreceptors may disappear.     

Ethanol effects on synaptic neurotransmission and tetanus-induced synaptic plasticity in hippocampal slices of chronic in vivo lead-exposed adult rats

The interaction of chronic in vivo lead exposure and acute in vitro ethanol treatment on synaptic neurotransmission and plasticity were studied using extracellular electrophysiological techniques in CA1 region of hippocampal brain slices from adult rats. Neither chronic lead exposure nor acute ethanol treatment had any significant effect on field excitatory postsynaptic potentials (EPSPs). In vivo lead exposure enhanced short-term potentiation (STP, potentiation that decays within 30 min) by 21% shortly after 'weak' tetanus, but had no effect on long-term potentiation (LTP, sustained at least 1 h). In vitro bath application of 60 mM ethanol inhibited STP by 35% and blocked LTP induced by 'weak' tetanus in slices from Pb exposed rats (500 ppm lead acetate, 56-70 days), while having no effect on STP or LTP in slices from control counterpart Na-exposed rats (pair-fed 216 ppm sodium acetate). In contrast, 'strong'-tetanus-induced LTP was abolished in Pb-exposed slices, and 60 mM ethanol slightly inhibited STP and blocked LTP in slices from Na-exposed rats. These differences could not be explained by differences in ethanol inhibition of NMDA-mediated field EPSPs because they were similarly reduced in slices from Na-exposed (30%) and Pb-exposed (25%) rats. These findings suggest that the strength of the tetanus used determines whether or not synaptic plasticity is blocked by either chronic lead exposure or acute ethanol treatment, and that even in adult rats, hippocampal synaptic LTP can be compromised by combined exposure to ethanol and lead. More importantly, these findings suggest the consequences of combined lead exposure and alcohol abuse in the adult human population may not be fully recognized yet.     

Bis-naphthalimides 3: synthesis and antitumor activity of N,N''-bis[2-(1,8-naphthalimido)-ethyl] alkanediamines

Gap junctions regulate a variety of cell functions by creating a conduit between two apposing tissue cells. Gap junctions are unique among membrane channels. Not only do the constituent membrane channels span two cell membranes, but the intercellular channels pack into discrete cell-cell contact areas forming in vivo closely packed arrays. Gap junction membrane channels can be isolated either as two-dimensional crystals, individual intercellular channels, or individual hemichannels. The family of gap junction proteins, the connexins, create a family of gap junctions channels and structures. Each channel has distinct physiological properties but a similar overall structure. This review focuses on three aspects of gap junction structure: (1) the molecular structure of the gap junction membrane channel and hemichannel, (2) the packing of the intercellular channels into arrays, and (3) the ways that different connexins can combine into gap junction channel structures with distinct physiological properties. The physiological implications of the different structural forms are discussed.     

Prevalence of comorbid anxiety disorders in primary care outpatients

OBJECTIVE: To estimate the extent to which anxiety disorders (eg, panic disorder, phobia, and generalized anxiety disorder [GAD]) co-occur in patients with major medical and psychiatric conditions. DESIGN: Observational study. SETTING: Offices of primary care providers in three US cities, with mental health specialty providers included for comparative purposes. PATIENTS: Adult patients (N = 2494) with hypertension, diabetes, heart disease (congestive heart failure or myocardial infarction), current depressive disorder, or subthreshold depression. MEASURES: Current (past 12 months) and lifetime panic disorder, phobia, GAD, perceived need for help for emotional or family problems, and unmet need (ie, failure to get help that was needed). METHODS: Comparisons of the prevalence of anxiety comorbidity in medically ill nondepressed patients of primary care providers and in depressed patients of both primary care and mental health specialty providers. RESULTS: Among primary care patients, those with chronic medical illnesses or subthreshold depression had low rates of lifetime (1.5% to 3.5%) and current (1.0% to 1.7%) panic disorder, but those with current depressive disorder had much higher rates (10.9% lifetime and 9.4% current panic disorder). Concurrent phobia and GAD were more common (10.4% to 12.4% current GAD), especially among depressed patients (25% to 54% current GAD). Depending on the type of medical illness or depression, 14% to 66% of primary care patients had at least one concurrent anxiety disorder. Patient-perceived unmet need for care for personal or emotional problems was high among all primary care patients (54.6% to 72.9%). CONCLUSION: Primary care clinicians should be aware of the possible coexistence of anxiety disorders (especially GAD) among their patients with chronic medical conditions, but especially among those with current depressive disorder.     

Surgical rehabilitation of deafness

The critical effects of pH on the electronic absorption and fluorescence characteristics of the siderophore, pyochelin, are investigated. A single anionic species is shown to be sufficient to explain the data obtained under alkaline conditions. In acidic solutions, several competing ground- and excited-state equilibria are present, which lead to fluorescence emissions from both the protonated form of pyochelin and its phenolate ion. From the spectroscopic data we are also able to show that pyochelin interacts with zinc ions in the ground state via its anionic form, thereby confirming that this siderophore does not bind Fe(III) ions uniquely.