bluuebunny/crossref_metadata_2025 huggingface dataset:
Neurological complications in AIDS patients: the 1‐year retrospective study in Chiang Mai University, Thailand
Authors: Subsai K. , Kanoksri S. , Siwaporn C. , Helen L.
Published: November 2004

The first case of AIDS patient in the northern part of Thailand was reported in 1987 (Vithayasai et al., 1996), marking the outbreak of an epidemic. In our experience, the neurological involvement in AIDS patients seems to have changed in pattern and incidence during the last 8 years. We have conducted a retrospective study to review the incidence of AIDS‐defining diseases in the patients admitted to Chiang Mai University Hospital, Thailand during the period September 2001 to August 2002. There were 155 AIDS patients admitted during this specified period, 118 of which were male and 37 female, aged between 16 and 60. The incidence of neurological complications was 50.3 per 100 person‐years, in which central nervous system involvement account for 46.5 per 100 person‐years and peripheral nervous system involvement account for 3.8 per 100 person‐years. The incidence of cryptococcal meningitis appeared to be decreasing since 1994 whereas the incidence of cerebral toxoplasmosis appeared to be increasing. The incidence of cryptococcal meningitis, cerebral toxoplasmosis and cytomegalovirus (CMV) infection was 18.0, 14.8 and 7.0 per 100 person‐years, respectively. Other common non‐neurological AIDS‐defining illnesses in northern Thailand include pulmonary tuberculosis (15.4 per 100 person‐years), extra‐pulmonary tuberculosis (9.6 per 100 person‐years), and disseminated penicilliosis (12.2 per 100 person‐years). In this way and summarizing, in northern Thailand, the three most common neurological involvements before the era of highly active anti‐retroviral therapy are cryptococcal meningitis, cerebral toxoplasmosis and CMV infection. The incidence of cryptococcal meningitis appeared to be decreasing whereas the incidence of cerebral toxoplasmosis seemed to be increasing.
Confabulation, but not executive dysfunction discriminate AD from frontotemporal dementia
Authors: Nedjam Z. , Devouche E. , Dalla Barba G.
Published: November 2004

We examined confabulation and performance on frontal/executive tasks in Alzheimer's disease (AD) patients and patients with a diagnosis of probable frontotemporal dementia (FTD). Twenty‐two patients with probable AD, 10 patients with probable FTD and 32 normal control subjects entered the study. Executive functions were assessed with the Modified Card Sorting test; a verbal fluency test; the Cognitive Estimation test; and the Stroop test. Confabulations were assessed with a modified version of the Confabulation Battery. The Confabulation Battery included 10 questions tapping each of the following domains: Episodic Memory (memories of personal past episodes), Semantic Memory (knowledge of famous facts and famous people), and Personal Future (personal plans). The results revealed that both AD patients and FTD patients were clearly and equally impaired on tests of executive functions. Both patients’ groups confabulated across the three tasks of the Confabulation Battery, but FTD patients confabulated significantly more than AD patients on Episodic Memory and Personal Future. The results failed to provide any evidence of a correlation between the performance on frontal/executive tasks and the tendency to produce confabulatory reports. According to our results, confabulation, more than a deficit of frontal/executive functions, discriminate between AD and FTD. Therefore, screening for confabulation and, possibly, for other types of memory distortions may constitute a useful additional clinical tool in order to discriminate AD from FTD.
Chronic cortisol exposure promotes the development of a GABAergic phenotype in the primate hippocampus
Authors: McMillan Pamela J. , Wilkinson Charles W. , Greenup Lynne , Raskind Murray A. , Peskind Elaine R. , Leverenz James B.
Published: November 2004

Glucocorticoids regulate plasticity and survival of hippocampal neurons. Aberrant exposure to this steroid hormone can result in neurodegeneration, perhaps secondary to disruption of calcium homeostasis. Calbindin, a calcium‐binding protein that buffers excess calcium, may protect against neurodegeneration resulting from overabundance of intracellular calcium. In this study, we examined whether chronic treatment (1 year) with cortisol enhances hippocampal calbindin expression in primates. Calbindin is a marker for inhibitory neurons and the dentate gyrus is known to adopt an inhibitory phenotype in response to extreme conditions such as seizures. Thus, we hypothesized that chronic cortisol exposure may also promote a GABAergic phenotype. Therefore, we examined the expression of the GABA‐synthesizing enzyme glutamic acid decarboxylase. The expression of brain‐derived neurotrophic factor, which is responsive to glucocorticoids, was also examined. Our results demonstrate significant increases in calbindin, glutamic acid decarboxylase and brain‐derived neurotrophic factor in several regions of the primate hippocampus, including the dentate gyrus and CA3, in response to chronic cortisol exposure. These results suggest that chronic cortisol exposure may shift the balance towards a GABAergic phenotype, perhaps as part of a compensatory feedback mechanism to dampen the initial excitatory effects of glucocorticoids in the hippocampus.
Characterization of subpopulations of neurons producing melanin‐concentrating hormone in the rat ventral diencephalon
Authors: Cvetkovic Vesna , Brischoux Frédéric , Jacquemard Claude , Fellmann Dominique , Griffond Bernadette , Risold Pierre‐Yves
Published: November 2004

Neurons producing melanin‐concentrating hormone (MCH) are involved in a large array of functions. Some of these functions may be mediated by specific subpopulations. One such subpopulation was characterized by the expression of the neurokinin 3 receptor and the ‘cocaine‐ and amphetamine‐regulated transcript’ (CART) peptide, while another expresses neither one of these two molecules. MCH+/CART+ axons were traced throughout the brain and showed a strikingly different pattern of distribution than that of MCH+/CART– axons. Particularly, many MCH+/CART+ axons are observed in the telencephalon, while MCH+/CART– projections are mostly directed toward the brainstem. Calbindin, a protein involved in calcium homeostasis, has been largely used in many structures of the brain for the identification of neuronal phenotypes. However, few MCH neurons were labeled for this protein. On the other hand, neurons producing the peptides hypocretins (Hcrt), and codistributed with the MCH neurons, were all labeled for calbindin. Thus, at least two subpopulations of MCH neurons can be distinguished on the basis of neuronal phenotypes and connections. These neurons may be involved in distinct circuitry and in distinct functions.
Ambulatory combined pH, bile and manometric monitoring of the oesophagus in asymptomatic healthy volunteers
Authors: Freedman Jacob , Lindqvist Madeleine , Melcher Anders , Granström Lars , Näslund Erik
Published: November 2004

Background:  With the development of sophisticated equipment ambulatory studies of oesophageal motor function, pH and bilirubin have gained in popularity. The aim of the study was to present reference values for combined 24 h pH, bilirubin and manometric measurements of the oesophagus.

Methods:  Twenty‐six (15 male) healthy volunteers without symptoms of gastro‐oesophageal reflux underwent a 24‐h ambulatory oesophageal combined three‐channel pressure, acid and bilirubin detection.

Results:  The subjects were studied for a median of 20 h (16–22). The median per cent time with pH < 4 for the whole measured time was 3·1 (0·8–14; 5 and 95 percentiles). Bile was detected for a median of 0·05% (0·0–8·5; 5 and 95 percentiles) of the time. Eighty‐one per cent of the contractions were peristaltic, 55% of which were complete. Of these, 53% had a pressure over 30 mmHg at all three pressure points, giving an efficient peristalsis in a median of 29% (13–46; 5 and 95 percentiles) of all registered contractile patterns. No difference between the genders could be observed.

Conclusions:  This study provides normative data for ambulatory oesophageal manometry, pH and bilirubin studies that can be used for comparing with patients with disease.
Aerobic and functional capacity in a group of healthy women: reference values and repeatability
Authors: Wisén Anita G. M. , Wohlfart Björn
Published: November 2004

Twenty‐five randomly selected, low or moderately fit and healthy women (22–44 years) rated their perceived physical capacity and performed an incremental cycle exercise test with respiratory gas analysis. The aerobic and functional capacity did not decrease with age. However, τo2 increased with age. The mean value of the perceived physical capacity was 10 metabolic equivalents and that of o2max 2075 ml min−1. The increasing anaerobic metabolism was determined at three points DX (where the rate of co2 increase just exceeds the rate of o2 increase), PX (where co2/o2 = 1·0) and PQ (where ventilation increase disproportionately in relation to co2). The mean o2 (% of o2max) at DX, PX and PQ were 1263 (63%), 1528 (73%) and 1620 (78%) ml min−1, respectively. The mean value of Δo2/ΔW was 10·2 ml min−1 W−1 while that of τo2 was 0·578 (age) + 15·6. Ten women performed a test and re‐test on two consecutive days, and eight of these performed another re‐test 4 weeks later. The repeatability was analysed and the variations were expressed as 2 SD of the differences between the tests. The variation was greater for the 4‐week re‐test than the day‐to‐day re‐test regarding o2max, o2 at DX, PX and PQ, Δo2/ΔW and HR. The variation in o2max, PX and Δo2/ΔW for the 4‐week re‐test was more than twice that of the previously reported 4‐week variation for men. The considerable variation, especially for 4‐week re‐testing for women should be considered when evaluating the effects of exercise and rehabilitation.
Determinants of hypertension and left ventricular function in end stage renal failure: a pilot study using cardiovascular magnetic resonance imaging
Authors: Stewart Graham A. , Mark Patrick B. , Johnston Nicola , Foster John E. , Cowan Michael , Rodger R. Stuart C. , Dargie Henry J. , Jardine Alan G.
Published: November 2004

Cardiovascular disease is the principal cause of mortality in patients with renal failure. Left ventricular (LV) abnormalities are adverse prognostic indicators for cardiovascular outcome. The aim of this study was to use cardiac magnetic resonance scanning (CMR) to define LV functional abnormalities in haemodialysis (HD) patients and clarify the determinants of blood pressure (BP) and the effect of anaemia in this population. We studied 44 HD patients and 11 controls with CMR performed following dialysis. Forty patients and 11 controls completed the study. LV mass (P<0·001) and estimated systemic vascular resistance (SVR) (P = 0·002) were significantly higher in the dialysis group compared to controls. LV ejection fraction (P = 0·002) and SV (P = 0·043) were lower than controls. In the HD patients, BP correlated significantly with cardiac output (CO; r = 0·569, P<0·001) and end diastolic volume (EDV; r = 0·565, P<0·001) but there was no correlation between BP and SVR (r = 0·201, P = 0·594). Haemoglobin was inversely correlated with both CO (r = −0·531, P<0·001) and EDV (r = −0·493, P = 0·001) and positively with SVR (r = 0·402, P = 0·009). HD patients had a higher LV mass and lower ejection fraction than controls. The relationship of BP with CO, but not SVR, supports the theory that a major determinant of BP is intravascular volume and CO rather than vascular resistance although there was a fixed increase in SVR in this population. Improved understanding of the mechanisms underlying increased SVR and improved control of CO and intravascular volume may allow better therapeutic strategies. CMR provides insights into the pathophysiology of hypertension and LV dysfunction in HD patients.
Jealousy and commitment: Perceived threat and the effect of relationship alternatives
Authors: Rydell Robert J. , McConnell Allen R. , Bringle Robert G.
Published: November 2004

Most research on jealousy has focused on the correlation between one psychological factor and jealousy. In contrast, the current work examined how the link between relationship commitment and jealousy depends on the interplay of two situational factors: attractiveness of relationship alternatives and receiving threatening information about the self and the romantic relationship. In two studies, participants completed measures of relationship commitment for their current relationship and then received feedback that manipulated their perceptions of relationship alternatives (Study 1) or their perceptions of relationship compatibility (Study 2). Participants' jealousy was assessed by their responses to a mildly threatening relationship situation (Studies 1 and 2) and on a jealousy scale (Study 2). Study 1 showed that those in more committed relationships experienced greater jealousy when they were induced to consider having unattractive relationship alternatives. Study 2 showed that those with greater relationship commitment reported more jealousy when they received negative information about their relationship compatibility. Implications for how threat plays a causal role in experiencing jealousy are discussed.
The composition of attachment networks throughout the adult years
Authors: Doherty Nicole A. , Feeney Judith A.
Published: November 2004

This study assessed the structure of adults' attachment networks, using a questionnaire measure of preferred attachment figures with a large sample of adults (N = 812) representing various ages and life situations. Two broad research questions were addressed. The first question concerned the variety of attachment figures reported by adults and the relative strength of attachment to each, including preferred (primary) attachment figures. The second question concerned the effects of normative life events on attachment networks and the nature of primary attachment figures in different life situations. Overall, the results supported the preeminent role of attachment relationships with romantic partners. However, relationships with mothers, fathers, siblings, children, and friends also met the strict criteria used to define full‐blown attachments; further, each of these targets constituted the primary attachment figure for some participants. The structure of the attachment network was related to variables such as age, relationship status, and parental status, attesting to the important role of normative life events. The results have theoretical and applied significance and are related to principles of attachment, caregiving, and socioemotional selectivity.
The enigma of altruistic lying: Perspective differences in what motivates and justifies lie telling within romantic relationships
Authors: Kaplar Mary E. , Gordon Anne K.
Published: November 2004

Lie tellers in intimate relationships often claim their lies were told to protect their partner. However, based on several converging theories (e.g., motivated reasoning, cognitive dissonance), we expected lie receivers to interpret lie tellers' motives less altruistically. We also made predictions regarding other variables on which we expected lie tellers' and lie receivers' perceptions to differ (e.g., justifications for the lie and responses to the lie, lie tellers' guilt, the temporal and situational context of the lies, perceptions of causality and blame). Participants wrote 2 autobiographical narratives, one from the perspective of lie teller and the other from the perspective of lie receiver. Participants also completed questionnaire items that mirrored the coding dimensions used in our content analyses of the narratives. As predicted, results indicated that the same participants, when occupying the role of lie teller as opposed to lie receiver, viewed their lies as more altruistically motivated, guilt inducing, spontaneous, justified by features of the situation, and provoked by the lie receiver. We discuss potential explanations for perspective differences in lying, the value of multiple perspectives when studying and evaluating lies, and the potential for an understanding of perspective differences to aid in conflict resolution.
The impact of suicidal ideation in preadolescence, adolescence, and young adulthood on psychosocial functioning and psychopathology in young adulthood
Authors: Steinhausen H.‐C. , Winkler Metzke C. W.
Published: November 2004

Objective:  The long‐term psychopathological outcome of suicidal ideation during adolescence in community samples is largely unknown. Data from the epidemiological and longitudinal Zurich Adolescent Psychology and Psychopathology Study (ZAPPS) allowed the testing of whether transient suicidal ideation in preadolescence or adolescence has the same impact on young adult psychopathology as enduring and concomitant suicidality in young adulthood.

Method:  Using various questionnaires on psychosocial functioning and the structured Composite International Diagnostic Interview (CIDI), the following five groups were compared: preadolescent suicidal ideation only, adolescent suicidal ideation only, young adult suicidal ideation only, enduring suicidality and young adult controls matched by age and gender.

Results:  The young adult and the enduring risk group were most abnormal in various domains of psychosocial functioning and psychopathology. Whereas these groups differed from controls and the adolescent suicidal risk group, the differentiation from the preadolescent risk group was much weaker.

Conclusion:  There is a heightened risk of abnormal psychosocial and psychopathological functioning for young adult people with enduring and concomitant suicidal ideation and for those who experienced suicidal ideation in preadolescence.
Cognitive performance of male adolescents is lower than controls across psychiatric disorders: a population‐based study
Authors: Weiser M. , Reichenberg A. , Rabinowitz J. , Knobler H. Y. , Lubin G. , Yazvitzky R. , Nahon D. , Gur R. C. , Davidson M.
Published: November 2004

Objective: Psychiatric patients, as well as humans or experimental animals with brain lesions, often concurrently manifest behavioral deviations and subtle cognitive impairments. This study tested the hypothesis that as a group, adolescents suffering from psychiatric disorders score worse on cognitive tests compared with controls.

Method: As part of the assessment for eligibility to serve in the military, the entire, unselected population of 16–17‐year old male Israelis undergo cognitive testing and screening for psychopathology by the Draft Board. We retrieved the cognitive test scores of 19 075 adolescents who were assigned any psychiatric diagnosis, and compared them with the scores of 243 507 adolescents without psychiatric diagnoses.

Results: Mean test scores of cases were significantly poorer then controls for all diagnostic groups, except for eating disorders. Effect sizes ranged from 0.3 to 1.6.

Conclusion: As group, adolescent males with psychiatric disorders manifest at least subtle impairments in cognitive functioning.
Late puerperal thrombohemorrhagic complications in a patient with antiphospholipid syndrome
Authors: Bladt V. , Steengaard‐Pedersen K. , Poulsen L. H. , Petersen O. B. , Laursen B. , D'Amore F.
Published: November 2004

Abstract:  In this study, we present a case of late‐puerperal onset of thrombohemorrhagic complications in a 33‐yr‐old woman with known antiphospholipid syndrome (APS) and heterozygosity for factor V Leiden gene mutation. Antithrombotic prophylaxis with low‐molecular‐weight (LMW) heparin was given since the 12th gestational week. Pregnancy and cesarean delivery were uncomplicated. Five weeks postpartum, the patient developed a severe hemorrhagic diathesis with marked thrombocytopenia accompanied by vaginal, nasal and cutaneous bleeding. A variety of autoimmune phenomena were also detected, partly at clinical presentation and partly later on, despite ongoing steroid treatment. Platelet counts recovered to normal values within a few weeks secondary to high‐dose steroids and intravenous immunoglobulin administration. An ultrasound of both legs, performed because of persistent complaint of moderate calf pain, revealed bilateral deep venous thromboses (DVT). The clinical and biochemical findings were not consistent with thrombotic thrombocytopenic purpura (TTP), heparin‐induced thrombocytopenia (HIT) or the ‘hemolysis, elevated liver enzymes and low platelet syndrome’ (HELLP). The diagnostic criteria for systemic lupus erythematosus (SLE) were not fulfilled either. The complex of thrombohemorrhagic complications and autoimmune phenomena seen in this case is unusual and not previously described in the late puerperal stage of APS‐related pregnancies.
Pregnancy in essential thrombocythaemia: experience with 40 pregnancies
Authors: Niittyvuopio Riitta , Juvonen Eeva , Kaaja Risto , Oksanen Kalevi , Hallman Heikki , Timonen Timo , Ruutu Tapani
Published: November 2004

Abstract: In this study, the course of 40 pregnancies in 16 women with essential thrombocythaemia (ET) was analysed retrospectively. Of the pregnancies, 45% were complicated, 55% uncomplicated, and 62% resulted in live birth. The most common complication was spontaneous abortion during the first trimester seen in 33% of all pregnancies and comprising 72% of all complications. Two intrauterine foetal deaths occurred at weeks 22 and 28. Three pregnancies were complicated by eclampsia or pre‐eclampsia. Nine of 16 women with 29 pregnancies had at least one complicated pregnancy. In seven of 16 women, all 11 pregnancies were uneventful. The non‐pregnancy‐related symptoms of ET or the platelet count before conception or during pregnancy did not correlate with the risk of pregnancy complications. Treatment with low‐dose acetylsalicylic acid (ASA) alone during pregnancy or platelet‐lowering drugs before or during pregnancy reduced the risk of complications.
Rituximab as treatment for minimal residual disease in hairy cell leukaemia
Authors: Cervetti Giulia , Galimberti Sara , Andreazzoli Francesca , Fazzi Rita , Cecconi Nadia , Caracciolo Francesco , Petrini Mario
Published: November 2004

Abstract:  Purine analogues have dramatically improved the outcome of patients affected by hairy cell leukemia (HCL), although complete eradication of disease was achieved in few cases. The purpose of this study was to evaluate the role of Rituximab in eradicating minimal residual disease (MRD) in HCL patients after a pre‐treatment with 2‐chloro‐deoxy‐adenosine (2‐CdA). Ten patients received four cycles of Rituximab after administration of Cladribrine. Before starting anti‐CD20 antibody, two patients were in complete remission, six in partial remission and two showed no significant response to Cladribrine. All cases resulted IgH‐positive. Median time from the last 2‐CdA infusion was 5.7 months. Eight of 10 patients [four in partial remission (PR), two in complete remission (CR) and two unresponsive after 2‐CdA] were evaluable for response. Two months after the end of anti‐CD20 therapy, all evaluated patients presented a complete haematological remission. Moreover, Rituximab increased percentage of molecular remission up to 100% 1 yr after the end of treatment. Interestingly, in all cases but one, including those persistently polymerase chain reaction (PCR)‐positive, semi‐quantitative molecular analyses showed MRD levels lower than those found before Rituximab administration. Toxicity was very mild. The present results not only confirm the therapeutic effect of Rituximab, but also show its relevance in eradicating MRD in HCL.
Intracellular Membrane Transport Systems in Trypanosoma brucei
Authors: Field Mark C. , Carrington Mark
Published: November 2004

Trypanosomes belong to the order kinetoplastida, an early diverging group of organisms in the eukaryotic lineage. The principal reasons for interest in these organisms are twofold; they provide a superb distant triangulation point from which to assess global features of eukaryotic biology and, more importantly, they are representative of a number of pathogenic parasitic protozoa with a huge public health impact –Trypanosoma brucei, T. cruzi and Leishmania spp. Recent advances in the study of intracellular transport in T. brucei have been considerable, and a fuller picture of the complexity, function and role that the endomembrane system plays in trypanosomes is finally emerging.
Differential Use of Two AP‐3‐mediated Pathways by Lysosomal Membrane Proteins
Authors: Ihrke Gudrun , Kyttälä Aija , Russell Matthew R. G. , Rous Brian A. , Luzio J. Paul
Published: November 2004

The adaptor protein complex AP‐3 is involved in the sorting of lysosomal membrane proteins to late endosomes/lysosomes. It is unclear whether AP‐3‐containing vesicles form at the trans‐Golgi network (TGN) or early endosomes. We have compared the trafficking routes of endolyn/CD164 and ‘typical’ lysosomal membrane glycoproteins (lgp120/lamp‐1 and CD63/lamp‐3) containing cytosolic YXXΦ‐targeting motifs preceded by asparagine and glycine, respectively. Endolyn, which has a NYHTL‐motif, is concentrated in lysosomes, but also occurs in endosomes and at the cell surface. We observed predominant interaction of the NYHTL‐motif with the μ‐subunits of AP‐3 in the yeast two‐hybrid system. Endolyn was mislocalized to the cell surface in AP‐3‐deficient pearl cells, confirming a major role of AP‐3 in endolyn traffic. However, lysosomal delivery of endolyn (or a NYHTL‐reporter), but not GYXXΦ‐containing proteins, was practically abolished when AP‐2‐mediated endocytosis or traffic from early to late endosomes was inhibited in NRK and 3T3 cells. This indicates that endolyn is mostly transported along the indirect lysosomal pathway (via the cell surface), rather than directly from the TGN to late endosomes/lysosomes. Our results suggest that AP‐3 mediates lysosomal sorting of some membrane proteins in early endosomes in addition to sorting of proteins with intrinsically strong AP‐3‐interacting lysosomal targeting motifs at the TGN.
Lipid Raft‐Dependent Targeting of the Influenza A Virus Nucleoprotein to the Apical Plasma Membrane
Authors: Carrasco Marlene , Amorim Maria Joao , Digard Paul
Published: November 2004

Influenza virus acquires a lipid raft‐containing envelope by budding from the apical surface of epithelial cells. Polarised budding involves specific sorting of the viral membrane proteins, but little is known about trafficking of the internal virion components. We show that during the later stages of virus infection, influenza nucleoprotein (NP) and polymerase (the protein components of genomic ribonucleoproteins) localised to apical but not lateral or basolateral membranes, even in cell types where haemagglutinin was found on all external membranes. Other cytosolic components of the virion either distributed throughout the cytoplasm (NEP/NS2) or did not localise solely to the apical plasma membrane in all cell types (M1). NP localised specifically to the apical surface even when expressed alone, indicating intrinsic targeting. A similar proportion of NP associated with membrane fractions in flotation assays from virus‐infected and plasmid‐transfected cells. Detergent‐resistant flotation at 4 °C suggested that these membranes were lipid raft microdomains. Confirming this, cholesterol depletion rendered NP detergent‐soluble and furthermore, resulted in its partial redistribution throughout the cell. We conclude that NP is independently targeted to the apical plasma membrane through a mechanism involving lipid rafts and propose that this helps determine the polarity of influenza virus budding.
Protein Kinase A Affects Trafficking of the Vesicular Monoamine Transporters in PC12 Cells
Authors: Yao Jia , Erickson Jeffrey D. , Hersh Louis B.
Published: November 2004

Previous studies have shown that the vesicular monoamine transporter 2 (VMAT2) is localized to both large dense core vesicles and synaptic vesicles in vivo. However, when exogenously expressed in PC12 cells, VMAT2 localizes only to large dense core vesicles. This distribution is similar to that of the endogenous vesicular monoamine transporter 1 (VMAT1) in PC12 cells. When VMAT2 was expressed in a protein kinase A (PKA)‐deficient PC12 cell line it localized to synaptic‐like microvesicles. Expression of recombinant VMAT1 in the same cell line showed a heterogeneous distribution to both large dense core vesicles and synaptic‐like microvesicles. Coexpression of the PKA catalytic subunit partially restored trafficking of both VMAT2 and VMAT1 to large dense core vesicles; treatment of wild‐type PC12 cells with the PKA inhibitor H89 increased VMAT2 on synaptic‐like microvesicles. The VMAT1 and VMAT2 in large dense core vesicles exhibit a larger molecular size than those located on synaptic‐like microvesicles. This difference is due to differential N‐linked glycosylation. In vitro phosphorylation experiments show that PKA does not phosphorylate VMAT2. A chimera containing the VMAT2 cytoplasmic C‐terminus fused to vesicular acetylcholine transporter (VAChT) shows mislocalization to synaptic‐like microvesicles and VAChT‐like glycosylation in the PKA‐deficient cell line. However, coexpression with PKA changes the chimera's trafficking to large dense core vesicles and increases the molecular size. These results suggest that protein kinase A affects the formation and/or composition of VMAT trafficking complexes.
ITI implants and Dolder bars in the treatment of large traumatic defect of mandible: a clinical report
Authors: Aydın Murat , Yılmaz Ayşe , Kâtiboğlu Bülent , Tunç Elif Pak
Published: November 2004

Abstract –  The development of more sophisticated implant techniques to produce satisfying results improves the precise planning of both the surgical phase of the implantation and the following prosthetic rehabilitation. Ball and bar attachments are the main retainer systems for implant‐bearing overdentures to achieve a successful treatment in the partial or full edentulism. In this clinical report, a 23‐year‐old male patient, presented with a large traumatic defect in the anterior mandible, was treated with ITI® implant and ITI® Dolder bar combinations. The reason to prefer this kind of treatment depends on the highest retention capacity and cleaning facilities of the system.
Infant weight‐for‐length is positively associated with subsequent linear growth across four different populations
Authors: Dewey Kathryn G. , Hawck Mette G. , Brown Kenneth H. , Lartey Anna , Cohen Roberta J. , Peerson Janet M.
Published: November 2004

Several studies have documented that length gain often lags behind weight gain during infancy and early childhood, suggesting that linear growth is partly regulated by initial body mass or fatness. To investigate this hypothesis, we analysed data from four longitudinal studies on growth of infants in the first 12 months: (1) U.S. breast‐fed and formula‐fed infants (n = 89); (2) breast‐fed infants in Ghana (n = 190); (3) normal birthweight, breast‐fed infants in Honduras (n = 108); and (4) term, low‐birthweight breast‐fed infants in Honduras (n = 119). The dependent variable was length gain during each 3‐month interval (1– 4, 2–5, 3–6, 4–7, 5–8, 6–9, 7–10, 8–11 and 9–12 months). Three main independent variables were examined: initial weight‐for‐length z‐score (W/L), weight change during the prior 3 months, and initial skinfold thickness. Controlling for maternal height, infant sex, and initial length‐for‐age z‐score, length gain was positively correlated with initial W/L and prior weight change during all age intervals and with initial skinfold thickness at 3 and 4 months (r = 0.15–0.36; P < 0.01). There was no evidence of a threshold effect. These associations were evident in all four populations, in both boys and girls, and in breast‐fed and formula‐fed infants. The consistency of this relationship across studies supports the hypothesis that linear growth is partly regulated by initial body mass or fatness in infants.
Government funded breastfeeding peer support projects: implications for practice
Authors: Dykes Fiona
Published: November 2004

In 1999, the Government, Department of Health in England, UK established the Infant Feeding Initiative. As part of this initiative, 79 1‐year infant feeding projects were selected for funding. The funded projects specifically centred upon practice innovation and evaluation in relation to promoting breastfeeding and supporting breastfeeding women in socially excluded communities. The DH recently commissioned a comprehensive evaluation of the 79 projects (DH 2003). This paper focuses upon the evaluation of the 26 DH funded projects that specifically focused upon breastfeeding peer support schemes. The evaluation illuminated many of the challenges involved in implementing community based breastfeeding peer support schemes. Lessons learnt from the most effective projects in terms of: potential to increase breastfeeding initiation and continuation rates; uptake of the service; comprehensive evaluation; and sustainability are presented here, as a series of steps required for successful operationalization of breastfeeding peer support schemes. When these steps are followed, peer support schemes offer exciting prospects for supporting breastfeeding women and increasing breastfeeding initiation and continuation rates, while respecting diversity, ensuring inclusivity and stimulating community empowerment.
Activation of NMDA receptors is required for the initiation and maintenance of walking-like activity in the mudpuppy (Necturus Maculatus)
Authors: Lavrov Igor , Cheng Jianguo
Published: November 2004

We hypothesized that blocking the activation of N-methyl-D-aspartate (NMDA) receptors prevents the initiation of walking-like activity and abolishes the ongoing rhythmic activity in the spinal cord - forelimb preparation from the mudpuppy. Robust walking-like movements of the limb and rhythmic alternating elbow flexor–extensor EMG pattern characteristic of walking were elicited when continuous perfusion of the spinal cord with solution containing D-glutamate. The frequency of the walking-like activity was dose-dependent on the concentration of D-glutamate in the bath over a range of 0.2 to 0.9 mmol/L. Elevation of potassium concentrations failed to induce walking-like activity. Application of the selective antagonist 2-amino-5-phosphonovalerate (AP-5) produced dose-dependent block of the initiation and maintenance of walking-like activity induced by D-glutamate. Complete block of the activity was achieved when the concentration of AP-5 reached 20 µmol/L. Furthermore, application of L-701,324 (a selective antagonist of the strychnine-insensitive glycine site of NMDA receptor) (1–10 µmol/L) also resulted in complete block of the walking-like activity. In contrast, application of the non-NMDA receptor antagonist 6-cyno-7-nitroquinoxaline-2,3-dione (CNQX) (1–50 µmol/L) induced a dose-dependent inhibition of the burst frequency but failed to result in a complete block. Only at concentration as high as 100 µmol/L, did CNQX cause complete block of the rhythmic activity, presumably through nonspecific action on the strychnine-insensitive glycine site of NMDA receptors. These results suggest that activation of NMDA receptors is required for the initiation and maintenance of walking-like activity. Operation of non-NMDA receptors plays a powerful role in the modulation of the walking-like activity in the mudpuppy.Key words: locomotion, central pattern generator, spinal cord, mudpuppy, glutamate, glycine, N-methyl-D-aspartate (NMDA)-receptor, 2-amino-5-phosphonovalerate (AP-5), 6-cyno-7-nitroquinoxaline-2,3-dione (CNQX).
Direct and indirect assessment of γ-motor firing patterns
Authors: Taylor A , Durbaba R , Ellaway P H
Published: November 2004

The study of the patterns of γ-motor activity which accompany natural contractions has been long and difficult, and has not as yet led to general agreement. In this review we have simplified matters by considering the case of locomotion in the cat only, and we have avoided discussion of the various hypotheses which have been advanced to provide general schemes of γ control for a wide range of movements. The development of the subject is shown to depend very much on devising ingenious methods applicable to reduced and intact animals. Direct recording from γ-motoneurones has only been possible in reduced preparations, whereas indirect assessment of γ activity from spindle afferent recordings was used in these and in intact animals. At this point in time, we still have no direct recordings from γ-motoneurones in normally behaving animals, but those obtained in decerebrate animals show distinct patterns of modulation for static and dynamic types with particular temporal relation to the stepping movements. The spindle recordings in intact animals potentially provide the most important information, and the problems of interpretation, which have previously caused difficulties, are beginning to be solved through the insights obtained from the reduced preparations.Key words: locomotion, gamma motoneurons, muscle spindles.
Possible contributions of CPG activity to the control of rhythmic human arm movement
Authors: Zehr E Paul , Carroll Timothy J , Chua Romeo , Collins David F , Frigon Alain , Haridas Carlos , Hundza Sandra R , Thompson Aiko Kido
Published: November 2004

There is extensive modulation of cutaneous and H-reflexes during rhythmic leg movement in humans. Mechanisms controlling reflex modulation (e.g., phase- and task-dependent modulation, and reflex reversal) during leg movements have been ascribed to the activity of spinal central pattern generating (CPG) networks and peripheral feedback. Our working hypothesis has been that neural mechanisms (i.e., CPGs) controlling rhythmic movement are conserved between the human lumbar and cervical spinal cord. Thus reflex modulation during rhythmic arm movement should be similar to that for rhythmic leg movement. This hypothesis has been tested by studying the regulation of reflexes in arm muscles during rhythmic arm cycling and treadmill walking. This paper reviews recent studies that have revealed that reflexes in arm muscles show modulation within the movement cycle (e.g., phase-dependency and reflex reversal) and between static and rhythmic motor tasks (e.g., task-dependency). It is concluded that reflexes are modulated similarly during rhythmic movement of the upper and lower limbs, suggesting similar motor control mechanisms. One notable exception to this pattern is a failure of contralateral arm movement to modulate reflex amplitude, which contrasts directly with observations from the leg. Overall, the data support the hypothesis that CPG activity contributes to the neural control of rhythmic arm movement.Key words: central pattern generator, locomotion, motor control, neural control.
What visual information is used for navigation around obstacles in a cluttered environment?
Authors: Patla Aftab E , Tomescu Sebastian S , Ishac Milad G.A
Published: November 2004

The goal of this study was to determine what visual information is used to navigate around barriers in a cluttered terrain. Twelve traffic pylons were arranged randomly in a 4.55 × 3.15 m travel area: there were 20 different arrangements. For each arrangement, individuals (N = 6) were positioned in 1 of 3 locations on the outside border with their eyes closed: on verbal command they were instructed to open their eyes and quickly go to 1 of 2 specified goals (2 vertical posts defining a door) located on one edge of the travel area. The movement of the body was tracked using the OPTOTRAK system, with the IREDS placed on a collar worn by the subjects. Experimental data of travel path chosen were compared with those predicted by models that incorporated different types of visual information to control path trajectory. The 6 models basically use 2 different strategies for route selection: reactive control based on visual input about the obstacle encountered in the line-of-sight travel path (Model # 1) and path planning based on different visual information (Model # 2, 3, 4, 5, and 6). The models that involve path planning are grouped into 2 categories: models 2, 3, 4, and 5 need detailed geometrical configuration of the obstacles to plan a route while model 6 plans a route based on identifying and avoiding a cluster of obstacles in the travel path. Two measures were used to compare model performance with the actual travel path: the difference in area between predicted and actual travel path and the number of trials that accurately predicted the number of turns during travel. The results suggest that route selection is not based on reactive control, but does involve path planning. The model that best predicts the travel paths taken by the individuals uses visual information about cluster of obstacles and identification of safe corridors to plan a route.Key words: navigation, obstacle avoidance, vision, path planning.
Associations between force and fatigue in fast-twitch motor units of a cat hindlimb muscle
Authors: Laouris Y , Bevan L , Reinking R M , Stuart D G
Published: November 2004

Associations were quantified between the control force and fatigue-induced force decline in 22 single fast-twitch-fatigable motor units of 5 deeply anesthetized adult cats. The units were subjected to intermittent stimulation at 1 train/s for 360 s. Two stimulation patterns were delivered in a pseudo-random manner. The first was a 500-ms train with constant interpulse intervals. The second pattern had the same number of stimuli, mean stimulus rate, and stimulus duration, but the stimulus pulses were rearranged to increase the force produced by the units in the control (prefatigue) state. The associations among the control peak tetanic force of these units, 3 indices of fatigue, and total cumulative force during fatiguing contractions were dependent, in part, on the stimulation pattern used to produce fatigue. The associations were also dependent, albeit to a lesser extent, on the force measure (peak vs. integrated) and the fatigue index used to quantify fatigue. It is proposed that during high-force fatiguing contractions, neural mechanisms are potentially available to delay and reduce the fatigue of fast-twitch-fatigable units for brief, but functionally relevant, periods. In contrast, the fatigue of slow-twitch fatigue-resistant units seems more likely to be controlled largely, if not exclusively, by metabolic processes within their muscle cells.Key words: cat, catch-like property, fatigue, force, motor units, size principle.
Adaptive changes of locomotion after central and peripheral lesions
Authors: Rossignol S , Brustein E , Bouyer L , Barthélemy D , Langlet C , Leblond H
Published: November 2004

This paper reviews findings on the adaptive changes of locomotion in cats after spinal cord or peripheral nerve lesions. From the results obtained after lesions of the ventral/ventrolateral pathways or the dorsal/dorsolateral pathways, we conclude that with extensive but partial spinal lesions, cats can regain voluntary quadrupedal locomotion on a treadmill. Although tract-specific deficits remain after such lesions, intact descending tracts can compensate for the lesioned tracts and access the spinal network to generate voluntary locomotion. Such neuroplasticity of locomotor control mechanisms is also demonstrated after peripheral nerve lesions in cats with intact or lesioned spinal cords. Some models have shown that recovery from such peripheral nerve lesions probably involves changes at the supra spinal and spinal levels. In the case of somesthesic denervation of the hindpaws, we demonstrated that cats with a complete spinal section need some cutaneous inputs to walk with a plantigrade locomotion, and that even in this spinal state, cats can adapt their locomotion to partial cutaneous denervation. Altogether, these results suggest that there is significant plasticity in spinal and supraspinal locomotor controls to justify the beneficial effects of early proactive and sustained locomotor training after central (Rossignol and Barbeau 1995; Barbeau et al. 1998) or peripheral lesions.Key words: spinal lesions, nerve lesions, locomotion, neuroplisticity, locomotor training.
Movements generated by intraspinal microstimulation in the intermediate gray matter of the anesthetized, decerebrate, and spinal cat
Authors: Mushahwar V K , Aoyagi Y , Stein R B , Prochazka A
Published: November 2004

The intermediate laminae of the lumbosacral spinal cord are suggested to contain a small number of specialized neuronal circuits that form the basic elements of movement construction ("movement primitives"). Our aim was to study the properties and state dependence of these hypothesized circuits in comparison with movements elicited by direct nerve or muscle stimulation. Microwires for intraspinal microstimulation (ISMS) were implanted in intermediate laminae throughout the lumbosacral enlargement. Movement vectors evoked by ISMS were compared with those evoked by stimulation through muscle and nerve electrodes in cats that were anesthetized, then decerebrated, and finally spinalized. Similar movements could be evoked under anesthesia by ISMS and nerve and muscle stimulation, and these covered the full work space of the limb. ISMS-evoked movements were associated with the actions of nearby motoneuron pools. However, after decerebration and spinalization, ISMS-evoked movements were dominated by flexion, with few extensor movements. This indicates that the outputs of neuronal networks in the intermediate laminae depend significantly on descending input and on the state of the spinal cord. Frequently, the outputs also depended on stimulus intensity. These experiments suggest that interneuronal circuits in the intermediate and ventral regions of the spinal cord overlap and their function may be to process reflex and descending activity in a flexible manner for the activation of nearby motoneuron pools.Key words: intraspinal microstimulation, spinal cord, gray matter, movement primitives.
The resilience of the size principle in the organization of motor unit properties in normal and reinnervated adult skeletal muscles
Authors: Gordon Tessa , Thomas Christine K , Munson John B , Stein Richard B
Published: November 2004

Henneman's size principle relates the input and output properties of motoneurons and their muscle fibers to size and is the basis for size-ordered activation or recruitment of motor units during movement. After nerve injury and surgical repair, the relationship between motoneuron size and the number and size of the muscle fibers that the motoneuron reinnervates is initially lost but returns with time, irrespective of whether the muscles are self- or cross-reinnervated by the regenerated axons. Although the return of the size relationships was initially attributed to the recovery of the cross-sectional area of the reinnervated muscle fibers and their force per fiber, direct enumeration of the innervation ratio and the number of muscle fibers per motoneuron demonstrated that a size-dependent branching of axons accounts for the size relationships in normal muscle, as suggested by Henneman and his colleagues. This same size-dependent branching accounts for the rematching of motoneuron size and muscle unit size in reinnervated muscles. Experiments were carried out to determine whether the daily amount of neuromuscular activation of motor units accounts for the size-dependent organization and reorganization of motor unit properties. The normal size-dependent matching of motoneurons and their muscle units with respect to the numbers of muscle fibers per motoneuron was unaltered by synchronous activation of all of the motor units with the same daily activity. Hence, the restored size relationships and rematching of motoneuron and muscle unit properties after nerve injuries and muscle reinnervation sustain the normal gradation of muscle force during movement by size-ordered recruitment of motor units and the process of rate coding of action potentials. Dynamic modulation of size of muscle fibers and their contractile speed and endurance by neuromuscular activity allows for neuromuscular adaptation in the context of the sustained organization of the neuromuscular system according to the size principle.Key words: motor unit size, motor unit recruitment, innervation ratio, reinnervation.