Perceived stress, quitting smoking, and smoking relapse

Assessed perceptions of stress prior to quitting and at 1, 3, and 6 months following quit date. Self-reported smoking status was augmented by a bogus pipeline procedure at each interview, and abstinence at 6 months was verified by carbon monoxide and saliva cotinine. The analyses provide strong evidence for a relation between changes in stress levels and changes in smoking status. Those who failed to quit smoking for more than 24 hr maintained a relatively high and consistent level of stress over the entire 6-month period. For those remaining continuously abstinent over the course of the study, stress decreased as duration of abstinence increased. Increases in stress with relapse were found across all three panel lags (prequit to 1 month, 1 to 3 months, and 3 to 6 months), and decreases in stress with quitting were found across the two lags where that comparison was possible. The possibility that the relation between smoking and stress is bidirectional is discussed as a possible interpretation of the results.

Tacrine or arecoline mediates reversal of anoxia- or AF64A-induced behavioural disorders in the developing rat

A 25 min anoxia, or an intracerebroventricular bilateral 2 nmol dose of ethylcholine aziridinium (AF-64A), administered postnatally to male rat pups, elicited on further development of these behavioural disorders, which are partly related to central cholinergic hypofunction. These included a hyperkinetic syndrome and inferior performance in the passive avoidance test. The anoxia-lesioned group but not the AF-64-A-lesioned one, showed an inferior performance in the active avoidance test. Administration of tacrine, an inhibitor of cholinesterase, or arecoline, a cholinergic agonist, in the drinking water to the nursing mothers, at an estimated daily dose of 15 and 10 mg/kg, then directly to the juvenile rats after weaning and until the age of 40 days, partly reversed the effects of anoxia or AF-64A, normalizing the level of locomotor activity and improving performance in passive avoidance, but not in active avoidance. These beneficial effects persisted long after discontinuation of administration of either drug, suggesting that stimulation of spared cholinoceptors in brain at development had prompted the recovery of cholinergic function.

Lipocortin I (p35) is abundant in a restricted number of differentiated cell types in adult organs

Lipocortin-I (p35) is a unique calcium- and phospholipid-binding protein of the lipocortin/calpactin family. Although several possibilities have been suggested, functions for the individual proteins of this family are not yet known with certainty. As an initial step in the identification of the biological function(s) of p35, we have used immunohistochemical methods to define precisely many of the cellular phenotypes that contain p35 in vivo. In all organs where p35 is found, we have observed a striking distribution of p35-positive cells. Typically it is highly enriched in a limited range of differentiated cell types while apparently totally absent from most others. Our identification of specific p35-positive cell types in vivo will now set limitations on likely possibilities for functions of this protein and thereby permit a more logical approach to the determination of its true function.

Debunking myths about self-quitting. Evidence from 10 prospective studies of persons who attempt to quit smoking by themselves

This article examines data from 10 longterm prospective studies (N greater than 5,000) in relation to key issues about the self-quitting of smoking, especially those discussed by Schachter. When a single attempt to quit was evaluated, self-quitters' success rates were no better than those reported for formal treatment programs. Light smokers (20 or less cigarettes per day) were 2.2 times more likely to quit than heavy smokers. The cyclical nature of quitting was also examined. There was a moderate rate (mdn = 2.7%) of long-term quitting initiated after the early months (expected quitting window) of these studies, but also a high rate (mdn = 24%) of relapsing for persons abstinent for six months. The number of previous unsuccessful quit attempts was unrelated to success in quitting. Finally, there were few occasional smokers (slips) among successful long-term quitters. We argue that quitting smoking is a dynamic process, not a discrete event.

Attachment of tumor cells to endothelial monolayers: detection of surface molecules involved in cell-cell binding

Trypsinization of P815 mastocytoma cells interferes with their ability to bind to endothelial monolayers in vitro, suggesting the involvement of proteins in cell-cell binding. Binding is also dependent upon divalent cations. Incubation of tumor cells with tunicamycin, which blocks protein glycosylation, or the monosaccharide N-acetyl-D-glucosamine could also inhibit binding. In addition, antibodies prepared against whole P815 cells had the ability to interfere with tumor cell binding. The protein fragments released from P815 cells by trypsin interfered with the binding of fresh P815 cells to endothelium. Moreover, those fragments as well as CHAPS extracts of tumor cell membranes were able to neutralize the inhibitory effect of an anti-P815 antibody on tumor cell-endothelial cell binding. These observations, taken together, strongly suggest the presence of adhesion molecules on the tumor cell. The anti-P815 antibody preparation could also inhibit endothelial binding of an unrelated tumor. Ehrlich ascites (EA). In addition, membrane preparations of EA could neutralize the antibody's effect on intact P815, and membrane preparations of P815 could neutralize the antibody's effect on EA. These observations suggest that there are common epitopes on these tumor cells and raise the possibility that a variety of tumors may share common mechanisms for attachment to endothelium. This, in turn, raises the possibility that monospecific antibodies against such epitopes might be useful agents for interfering with metastasis in vivo.

Differences in the pattern of proliferative response with age in thymocytes undergoing spontaneous and induced proliferation

The proliferative capacity of thymocytes from C3H/HeJ mice decrease as the animals attain maturity. The proliferative response of thymocytes from 24- to 28-week-old mice to stimulation with concanavalin A (Con A) is only 20% of that observed at 4 weeks of age. The decreased proliferative capacity of thymocytes in response to Con A stimulation observed between 4 and 24 weeks of age closely correlates to the drop in thymic weight and cellularity observed during this period. In contrast, the spontaneous proliferative capacity of thymocytes, as well as proliferation of thymocytes in response to stimulation with phorbol myristate acetate (PMA) and ionomycin, drops only slightly during this period, as proliferation under these condition in thymocytes from 24- to 28-week-old mice is approximately 65-70% of that observed in 4-week-old animals. We have previously shown that cytoplasmic extracts from proliferating lymphoid cells contain a factor, termed the activator of DNA replication (ADR), which is capable of inducing DNA synthesis in isolated, quiescent nuclei. We show in this study that the decreased proliferative capacity of thymocytes during whole organism maturation and thymic involution is associated with decreased endogenous levels of ADR, while nuclear sensitivity of thymocyte to ADR was retained during these process. The diminution of ADR activity during thymic involution was quantitatively greater than the loss in proliferative capacity.

Heterogeneity of human monocytes: differences in response to IFN-gamma

Human peripheral blood monocytes can be separated into two subpopulations which differ in the efficiency of their adherence to glass after 16 hours of incubation. The adherent subpopulation was found to be about twice as effective in binding mannose-resistant E. coli 0-124, mannose-sensitive E. coli 0-128 and opsonised E. coli than the nonadherent one. In addition, reduction of cytochrome C in response to E. coli binding or 12-myristate 13-acetate (PMA) stimulation was two fold higher in adherent cells. The binding of E. coli O-124 and the superoxide generation stimulated by E. coli were inhibited by the addition of mannose only in the adherent monocytes, indicating the presence of mannose receptors on the cell surface in the adherent subpopulation. The treatment of the nonadherent cells with 0.1-1000 U/ml of Interferon (IFN-gamma) for 24 hours resulted in a dose dependent increase in superoxide generation. After 72 hours of incubation with IFN-gamma (1000 U/ml) the amount of superoxide generated by the nonadherent cells was elevated to 20.5 +/- 1.4 nmoles/10(6) cells/15 min, similar to that of the adherent cells (24.5 +/- 1.2 nmoles/10(6) cells/15 min untreated adherent monocytes). The generation of superoxide in the IFN-gamma treated nonadherent monocytes stimulated by E. coli 0-128 was significantly reduced by addition of mannose.

Demographic and clinical features predictive of recovery in acute mania

Discrepancies exist in previous reports regarding clinical and demographic features associated with recovery in acute mania. The authors studied 44 hospitalized patients with bipolar affective disorder, manic type. They report a significant association between more depressive symptomatology and perhaps younger age of illness onset, and poor immediate treatment response. They also found the total amount of psychopathology at admission, as measured by the Brief Psychiatric Rating Scale and Manic State Rating Scale, and the degree of psychosis to be unrelated to immediate outcome. The authors suggest that the not recovered manic subgroup has a distinct illness or a variant of bipolar disorder with poor prognosis that warrants further and separate investigation.

Vasoactive intestinal peptide. An inhibitor of feline gastric smooth muscle in vitro

Dose-response characteristics of feline corpus circular muscle were studied in vitro for three neuropeptides individually and with vasoactive intestinal peptide. Bombesin, substance P, and cholecystokinin-octapeptide each elicited concentration-dependent isometric contractions that were reduced by 10(-8) M or 10(-7) M vasoactive intestinal peptide (P less than 0.01). The concentration of each neuropeptide producing a half-maximal response was increased more than one logfold to greater than or equal to 10(-6) M by vasoactive intestinal peptide. Tetrodotoxin blocked responses to bombesin (P less than 0.001) and reduced responses to substance P (P less than 0.05), but had no effect on responses to cholecystokinin-octapeptide (P greater than 0.1). These results demonstrate inhibition of neuropeptide responses of gastric smooth muscle and support vasoactive intestinal peptide as an inhibitory regulator of gastric motor function.

Nasal versus temporal preretinal vasoproliferation in retinopathy of prematurity

Nasal preretinal neovascularisations have been observed to develop at least two weeks earlier than those on the temporal side in more than a third of premature babies with retinopathy of prematurity (ROP) stage 3, weighing between 690 and 1030 g. All these babies were assigned for cryotherapy. This interesting observation is discussed in relation to retinal vascular development and the pathogenesis of ROP.

Arthroscopy update #5. Rehabilitation after arthroscopic lateral retinacular release

This study compares postoperative quadriceps strength with functional results in a homogeneous population with isolated anterior knee pain and patellofemoral instability. Although several factors may interfere with the success of lateral retinacular release, this study suggests that poor quadriceps rehabilitation is the single factor preventing total return to athletic participation in patients with lateral subluxation. Many patients seem to adopt changes in life-style in order to accommodate weakened quadriceps and remain symptom free.

Vascular cholinesterases and choline uptake in isolated rat forebrain microvessels: a possible link

The two parameters of the active [methyl-3H]choline uptake into isolated rat forebrain microvessels, Km and Vmax, were determined for 1-, 3-, 10-, and 24-month-old Charles River male rats and compared with the activities of the enzymes choline acetyltransferase (ChAT), acetylcholinesterase (AChE), and butyrylcholinesterase (BuChE) in these microvessels over the same time course. The value of Km remained constant over the entire period, but that of Vmax increased from 8.5 +/- 1.0 to 80.6 +/- 16.4 nmol g-1 (mean +/- SEM) over the first 3 months of life. Over the same period, the increase in ChAT activity, from an initial value of 7.1 +/- 1.6 to 10.2 +/- 0.3 nmol g-1 min-1, was not proportional to that of choline uptake. Levels of BuChE activity (0.9-1.3 mumol g-1 min-1) were almost unchanged throughout the entire 24-month period, but those of AChE showed a steady and significant increase from 1 to 24 months, remaining relatively high at senescence (4.7 mumol g-1 min-1), when choline uptake had decreased to one-third of its optimal value. Selective inhibition of AChE with 1,5-bis(4-allyldimethylammonium-phenyl)pentan-3-one dibromide (0.5 microM) in unruptured capillaries from 3-month-old rats resulted in a decrease in Vmax of choline uptake from approximately 81 to 59 nmol g-1 min-1 or with 9-amino-1,2,3,4-tetrahydroacridine (10 microM) in capillaries from 2-month-old rats from approximately 30 to 15 nmol g-1 min-1. Selective inhibition of BuChE with tetraisopropyl pyrophosphoramide (100 microM) resulted in an increase in Vmax from approximately 81 to 96 nmol g-1 min-1. It is possible that the two vascular enzyme systems are coupled to a hypothetical endothelial choline transporter, but with an action opposite to each other.

Semliki Forest virus E2 envelope epitopes induce a nonneutralizing humoral response which protects mice against lethal challenge

Along the 422 amino acids of the Semliki Forest virus (SFV) E2 envelope glycoprotein, we identified 13 peptide cassettes (ranging in size from 15 to 25 amino acids and designated A through N) that contain hydrophilic sequences flanked by amino acid sequences conserved in the E2 envelopes of the alphavirus family. Six peptide blocks containing either a single cassette or two to three contiguous cassettes (A, BC, DE, FG, HIK, and LMN) were produced in Escherichia coli as recombinant proteins fused to the N terminus of beta-galactosidase. All of the SFV E2 recombinant polypeptides except A-beta-galactosidase were recognized on Western blots (immunoblots) by anti-SFV polyclonal antisera. In addition, these five recombinant proteins induced in mice antibodies that interacted specifically with SFV E2 protein on Western blots as well as with the intact virions in an enzyme-linked immunosorbent assay. The six hybrid proteins were used to vaccinate mice and were tested for the ability to confer resistance against lethal doses of SFV. Peptides BC and HIK, located at amino acid positions 114 to 149 and 216 to 288, respectively, of E2, protected partially (40 to 60%) against SFV challenge. A third peptide, LMN, located between amino acid positions 289 and 352, rendered mice totally resistant to an SFV challenge of 250 50% lethal doses. The partially protective effects of the BC and HIK cassettes and the high efficacy of the LMN cassette were consistently demonstrated, independent of the adjuvant (complete Freund or alum), immunization protocol, and strain of mice used. None of the antisera raised against any given cassette could neutralize the virus in an in vitro tissue culture assay or in a plaque reduction neutralization test. Nevertheless, passive transfer experiments demonstrated that in the case of LMN, the protective effect was mainly of a humoral nature.

Colonic slow-wave analysis. Limitations of usefulness of fast Fourier transform (FFT)

The fast Fourier transform (FFT) has been used to determine frequency components of colonic slow-wave activity. We studied the effect of (1) recorder filter characteristics, (2) number of data points and, (3) data window overlap technique and ingestion of a 1000-kcal meal on the resulting power spectrum. Human rectosigmoid slow-wave activity was recorded in nine normal subjects and stored on FM tape for computer analysis. The dynograph filter characteristics were tested using square wave signals, and derived compensation factors were applied to the FFT before viewing. The dynograph filter, when set to optimize visualization of slow waves, attenuates low frequencies nonlinearly. Failure to compensate for the dynograph filter results in inaccurate detection of slow-wave frequencies. FFT of 1-min data gives a different power spectrum than an FFT of 4 min data, indicating a rapidly changing waveform. FFT's of 1 min of data when examined over time fail to demonstrate a consistent frequency spectrum, confirming this conclusion. The lower frequencies in the normal human rectosigmoid are present at the greatest power. These studies indicate that the colon has slow waves of irregular frequencies, in contrast to the stomach or small intestine. No change in the dominant frequency was seen following the ingestion of a 1000-kcal meal.

Degenerative arthritis of the carpus associated with congenital hypoplastic thumb

The case history of a young man with bilteral congenital hypoplastic thumbs and early degenerative arthritis involving the base of the thumb and scaphotrapeziotrapezoid joints is reported. To our knowledge this association has not been previously made. Limited intercarpal arthrodesis and/or trapezium arthroplasty may be required at a relatively early age in patients with thumb dysplasia. We believe the hypoplastic thenar musculature may lead to instability and excessive shear stresses on the radial side of the carpus, causing the early arthritic changes.

Protection of cattle from infection with vaccinia virus by bovine interferon alpha C

The efficacy of bovine interferon alpha C as an antiviral compound was evaluated in calves infected with vaccinia virus. Calves treated with the interferon did not develop characteristic vaccinia lesions, demonstrating a clear protective effect of treatment. The only side effect observed was hyperthermia. After intramuscular injection, interferon appeared quickly in the blood and was cleared within 24 hours. The in vivo antiviral activity of bovine interferon alpha C was confirmed by its ability to induce 2'5' A synthetase, an enzyme implicated in the antiviral state, in lymphocytes.

Expression of an intercellular adhesion molecule, ICAM-1, by human thyroid cells

Intercellular adhesion molecule-1 (ICAM-1), hitherto identified on activated B cells, macrophages, dendritic cells, endothelia and certain epithelial cells, serves as a ligand for the lymphocyte function-associated antigen-1 (LFA-1). ICAM-1 binding by LFA-1 enhances the efficiency of lymphocyte-target cell and lymphocyte-accessory cell interactions. We have investigated the in-vitro expression of ICAM-1 by cultured thyroid cells from five patients with Graves' disease using indirect immunofluorescence analysis, and found that 30 +/- 11% (mean +/- S.D.) of cells were ICAM-1 positive under basal conditions. The proportion of cells which were ICAM-1 positive and the amount of ICAM-1 per cell (assessed by fluorescence intensity) were both increased in all cases by the cytokines gamma-interferon, interleukin-1 and tumour necrosis factor. Immunohistochemical analysis of frozen sections from thyroidectomy specimens demonstrated ICAM-1 on thyroid follicular cells in areas of lymphocytic infiltration in patients with Graves' disease (n = 2) or Hashimoto's thyroiditis (n = 2). ICAM-1 was not found in specimens from a patient with a toxic multinodular goitre or a patient with Graves' disease without focal lymphocytic accumulation. These results suggest that the thyroid epithelium may express ICAM-1 as well as major histocompatibility complex class II antigens, such as HLA-DR, in response to locally synthesized cytokines. The enhanced expression of ICAM-1 may render these cells more susceptible as targets for lymphocyte-mediated cytotoxicity, and together with HLA-DR antigen expression may increase the accessory cell capability of the thyroid follicular cells.

Onset of response in relation to outcome in depressed outpatients with placebo and imipramine

We have retrospectively analyzed the results of the pooled data from three 6-week placebo controlled double blind phase III clinical trials, initially designed to assess the efficacy of newer antidepressants, in order to study the relationship of early onset improvement with later outcome in 145 depressed outpatients receiving placebo (n = 98) or imipramine (n = 47). The early onset response was seen in a subgroup of subjects receiving either imipramine or placebo and appeared to be independent of treatment assignment. Furthermore, the early onset response predicted outcome for the duration of the trial and was not selective as defined by specific changes in subscales measuring insomnia, anxiety or endogenous features. Exclusion of early onset responders resulted in the augmentation of the difference in outcome with drug and placebo. We recommend that future placebo controlled trials assessing therapeutic efficacy of active treatments in depressed outpatients take into account the early onset response in the analysis of results.