bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of the Akt kinase activation in a PTEN deficient canine osteosarcoma cell line
Authors: Dervisis N. G. , Kitchell B. E.
Published: August 2004

Introduction:  Osteosarcoma is a devastating disease in both human and veterinary medicine. The dog has been recognized as an important model system for the study of this disease, with a high incidence of tumor development noted annually. The cure rates in veterinary oncology are between 20 and 30% of patients seen. Akt is a serine/threonine kinase that primarily protects the cell from apoptosis and may prompt proliferation and growth. Akt activation involves sequential phosphorylation of threonine at position 308 (T308) and serine at position 473 (S473). While for the T308 phosphorylation responsible is PDK1 kinase, for S473 phosphorylation no definitive mechanism has yet been identified. The tumor suppressor PTEN, which has been reported to be absent in canine osteosarcoma, negatively regulates Akt. In our study we evaluated the Akt activation sequence in response to serum deprivation.

Methods:  “Buck,” an immortalized PTEN deficient canine OSA cell line established and characterized in our laboratory was used. Buck cells were grown in the absence of fetal bovine serum for 8, 24, and 48 hours. Activity of Akt was assayed directly by a method described by Kang et al. The phosphorylation status of Akt at T308 and S473, together with serine at position 241 (S241) of PDK1 was assessed by immunoblotting.

Results:  We noted marked decrease of the Akt kinase activity with the nadir at the 24‐hour time point and subsequent increase of Akt activity at the 48‐hour time point. Decoupling of the two Akt phosphorylation sites at the 24, and 48‐hour time points was observed (p < 0.01). The phosphorylation status of T308 declined steadily throughout the experiment. The phosphorylation status of S473 declined until the 24‐hour time point, and then increased in parallel with the results noted in the kinase activity assay. Phosphorylation of PDK1 S241 was examined and found to decrease at 24 hours, with subsequent increase after 48 hours of serum starvation, in parallel with the phosphorylation pattern of Akt S473 (p < 0.01).

Conclusions:  We report parallel patterns of PDK1 S241 and Akt S473 phosphorylation in the absence of growth factors. PDK1 activity is not assessed directly, but its phosphorylation status indicates that more PDK1 is in an activated from at the 48‐hour time point than at 24 hours. The increase of Akt activity and S473 phosphorylation at the 48‐hour time point is presumably a response to the apoptogenic conditions of the serum free medium. The same response of PDK1 may indicate the presence of a regulatory autophosphorylation mechanism that members of the AGC kinase family share. Surprisingly, the increased amount of activated PDK1 does not correlate with the phosphorylation pattern of Akt T308, and could be attributed to cytoplasmic sequestration of PDK1.
Clonality and clinical behavior of canine indolent lymphoma
Authors: Valli V. E. , Vernau W. , DeLorimier L. P. , Ehrhart E. J. , Chladny J. , Graham P. S.
Published: August 2004

Introduction:  Canine lymphomas with a follicular architecture are biologically indolent and include follicular (FL), mantle cell (MCL), marginal zone (MZL) and T‐zone (TZL) types. They are under recognized and have long survival regardless of treatment.

Methods:  70 cases of canine lymphoma with fading follicular hyperplasia (FFH) received1 over 1996 to present were reviewed. Diagnoses were determined by consensus of three pathologists1,2 on phenotyped tissues. Clonality for B and T‐cell receptor genes was determined on DNA from paraffin blocks via PCR on 53 of 70 cases2.

Results:  Of the total of 70 cases 52 were of B‐cell type (MZL 44, FL 4, MCL 3, MALT 1) and 9 were of T‐cell type (TZL). 9 cases of benign hyperplasia were included to assist in defining the histologic boundaries of neoplasia. Case presentation included splenic 16, and nodal 54. For 44 cases called MZL on histologic criteria, DNA was available on 33 of which 26 (78.8%) were clonal for B‐cell rearranged gene including 5 also clonal for T‐cell receptor, one clonal for T‐cell only and 6 cases negative for both and considered benign. For TZL, DNA was available on 6 of 9 cases of which 3 were clonal for T‐cell receptor, 1 for B‐cell, 1 for both and 2 polyclonal for both.

Conclusions:  An Ohio review of 380 cases of canine nodal lymphoma found 29% of cases to be of indolent type as described here and thus a very significant part of the patient population. Seven of 10 cases of MZL treated at Illinois with follow‐up died of other causes than lymphoma at an average of 18.8 months after diagnosis. One of the other three was lost to follow‐up, one was euthanized at owners’ choice at 9.5 m. after diagnosis still in good health and the other was terminated 3 m after diagnosis with concurrent lung carcinoma.
The Role of Pacemaker Currents in Neuropathic Pain
Authors: Brown Sean M. , Dubin Adrienne E. , Chaplan Sandra R.
Published: August 2004

Abstract:  Hyperpolarization‐activated cation nonselective cyclic nucleotide‐gated (HCN) channels mediate pacemaker currents that control basic rhythmic processes including heartbeat. Alterations in HCN channel expression or function have been described in both epilepsy and cardiac arrhythmias. Recent evidence suggests that pacemaker currents may also play an important role in ectopic neuronal activity that manifests as neuropathic pain. Pacemaker currents are subject to endogenous regulation by cyclic nucleotides, pH and perhaps phosphorylation. In addition, a number of neuromodulators with known roles in pain affect current density and kinetics. The pharmacology of a number of drugs that are commonly used to treat neuropathic pain includes effects on pacemaker currents. Altered pacemaker currents in injured tissues may be an important mechanism underlying neuropathic pain, and drugs that modulate these currents may offer new therapeutic options.
Side Effects of Antiepileptics— A Review
Authors: Walia Kulbir S. , Khan Elizabeth A. , Ko Dong H. , Raza Shariq S. , Khan Yasin N.
Published: August 2004

Abstract:  Older generation antiepileptic drugs like Phenobarbital (Luminal), carbamazepine (Tegretol), phenytoin (Dilantin), and valproic acid (Depakote) have several shortcomings such as suboptimal response rates, significant adverse effects, several drug interactions, and a narrow therapeutic index. New antiepileptic drugs have been developed in the last decade to overcome some of these problems. These newer generation antiepileptics like felbamate (Felbatol), gabapentin (Neurontin), lamotrigine (Lamictal), levetiracetam (Keppra), oxcarbazepine (Trileptal), tiagabine (Gabitril), topiramate (Topamax), and zonisamide (Zonegran) have better tolerability profiles, low interaction potential, and significantly less enzyme inducing or inhibiting properties. As the use of antiepileptic drugs has expanded to include treatment of neuropathic pain, newer side effects have been reported. In addition to the common side effects of antiepileptic drugs, like dizziness, drowsiness, and mental slowing; other side effects like weight gain, metabolic acidosis, nephrolithiasis, angle closure glaucoma, skin rash, hepatotoxicity, colitis, and movement and behavioral disorders, to name a few, have been brought to our attention. This review is an attempt to highlight the features and incidences of some of these side effects.
An Unusual Complication of Sinus Arrest Following Right‐Sided Stellate Ganglion Block: A Case Report
Authors: Saxena Ashok K. , Saxena Neeraj , Aggarwal Bhavna , Sethi Ashok K.
Published: August 2004

Abstract:  We present a case of a 29‐year‐old female patient who had presented to us for the management of her chronic right shoulder–hand pain and developed a sinus arrest following a right‐sided stellate ganglion block (RSGB). This patient on receiving a diagnostic RSGB via the anterior paratracheal (C6) approach developed sinus arrest followed by apnea and unconsciousness. On institution of resuscitative measures involving tracheal intubation, positive pressure ventilation, cardiac massage, and intravenous atropine, spontaneous cardiac activity recovered in about 3 minutes. Other signs and symptoms resolved fully in a total of 10 minutes. She had persistent postural hypotension lasting for about 24 hours requiring bed rest and was discharged about 36 hours after the procedure, without any adverse sequelae. As the sinus node is supplied by the right‐sided sympathetic chain, its blockade probably resulted in unopposed parasympathetic activity leading to asystole. Available evidence of the role of right stellate ganglion in regulation of cardiac electrophysiology and functioning is also discussed.
Whiplash Associated Disorders: Pathomechanics, Diagnosis, and Management
Authors: Sizer Phillip S. , Poorbaugh Keith , Phelps Valerie
Published: August 2004

Abstract:  Whiplash has been defined as an injury mechanism, an injury, a medico‐legal or social dilemma, and a complex chronic pain syndrome. Whiplash associated disorders are frequent in the cervical spine, especially as a result of a motor vehicle accident. The mechanisms responsible for whiplash‐related tissue trauma are complex and a clinician's understanding of these complexities lends to a more complete appreciation for the anatomical structures and pathological processes that are involved, as well as a comprehensive diagnosis and appropriate management. While several classification scales have been developed for whiplash associated disorders, a thorough and tissue‐specific examination is merited. Management should be directed toward pain reduction and normalization of mechanics. While conservative measures can address many of clinical sequelae of whiplash, both invasive pain management procedures and surgical interventions may be paramount to a patient's complete recovery.
A comprehensive assessment program to improve blood‐administering practices using the FOCUS–PDCA model
Authors: Saxena Sunita , Ramer Lois , Shulman Ira A.
Published: August 2004

BACKGROUND:  The Joint Commission on the Accreditation of Healthcare Organizations requires that hospitals have a planned approach to systematically collect data on processes related to the use, ordering, and administering of blood components. This study describes how a comprehensive blood‐administering assessment program and the FOCUS‐PDCA approach improved overall blood‐administering practices.

STUDY DESIGN AND METHODS:  Nurses were trained to observe blood issuance, blood administering, and patient monitoring steps, and to audit patient's charts to measure compliance with blood‐ordering procedures. The observations were recorded on a standardized scannable form, which allowed automatic entry of recorded data directly into a computer database.

RESULTS:  A total of 982 assessments were completed during the 51‐month study period. Documentation of informed consent improved from 80 percent to 100 percent. Compliance with a California law that requires patients to receive information on the risks, benefits, and alternatives to transfusion rose from 30 percent to 100 percent. Physicians’ compliance in specifying the rate of blood administration improved from 30 percent to 100 percent, and verification of information on the patient's identification band with the patient's self‐identification rose from 50 percent to 100 percent. For all other blood‐administering steps, compliance remained high throughout the study period. For the past 9 months, 100‐percent compliance has been maintained for all transfusion processes, and during this period no mistransfusions or blood administration near‐misses have been reported.

CONCLUSION:  The blood‐administering assessment program described above has improved transfusion practice, reduced the number of near‐miss events, and may have prevented mistransfusions.
Hepatitis C seroprevalence in accepted versus deferred blood‐donor candidates evaluated by medical history and self‐exclusion form
Authors: López Rafael Antonio Marín y , Romero‐Estrella Sagrario , Infante‐Ramírez Lilia , Méndez‐Aquino Jorge Saúl , Berrón‐Ruiz Patricia , Morales‐Alfaro Norma Angélica , Vivar Raúl , Carrada Etelvina , Rivera‐Rendón María del Refugio , Sánchez‐Guerrero Sergio Arturo
Published: August 2004

BACKGROUND:  Hepatitis C virus (HCV) represents a viral pandemic that is five times as widespread as human immunodeficiency virus. Blood transfusion posed a major risk of HCV infection in developed countries before 1990, but the introduction of improved blood‐screening measures has decreased the risk of transfusion‐associated HCV infection, which may now be even lower since the introduction of screening of pooled samples by nucleic acid testing (NAT). Unfortunately, NAT is not affordable in most developing countries. The goal of this work is to assess the usefulness of both screening measures, the medical history, and the self‐exclusion form to distinguish between high‐risk and low‐risk populations of HCV‐carrier blood‐donor candidates in Mexico.

STUDY DESIGN AND METHODS:  From February 2002 to April 2003, 4174 consecutive candidates were enrolled in a prospective, nonrandomized and comparative study. In total, 4158 candidates were included in the analysis and divided in two groups: Group A consisted of 3101 accepted donors and Group B consisted of 1057 deferred donors according to a complete medical history and self‐exclusion form. The only exclusion criteria was the lack of a signed consent form to enter the study. All candidates from both groups underwent anti‐HCV detection by third‐generation enzyme immunoassay (EIA). Those who had either a positive or gray‐zone signal‐to‐cutoff ratio underwent polymerase chain reaction and a second EIA test. If the second EIA test resulted in either a positive or gray‐zone signal‐to‐cutoff ratio, a recombinant immunoblot assay test was performed. The chi‐square test was used for statistical analysis, and a p value less than 0.05 was considered significant.

RESULTS:  Anti‐HCV prevalence by the EIA method was as follows: 0.61 percent for Group A and 1.32 percent for Group B (p = 0.0243); whereas with recombinant immunoblot assay the prevalence was 0.19 percent for Group A and 0.47 percent for Group B (p = 0.1265). When we analyzed the polymerase chain reaction test results, the prevalence in Group A was 0.10 percent (95% confidence interval, 0.089‐0.110) and in Group B was 0.47 percent (95% confidence interval, 0.439‐0.500) (p = 0.0159).

CONCLUSIONS:  The medical history of blood donors in conjunction with serologic screening tests helps to improve blood transfusion safety. This measure is recommended in blood banks of those countries where NAT is still unaffordable.
RhD variants in Caucasians: consequences for checking clinically relevant alleles
Authors: Ansart‐Pirenne Hélène , Asso‐Bonnet Marianne , Pennec Pierre‐Yves Le , Roussel Michèle , Patereau Claude , Noizat‐Pirenne France
Published: August 2004

BACKGROUND:  Weak D type carriers cannot be immunized against D except when antigen density is below 400 antigens per RBC, whereas partial D carriers can produce anti‐D.

STUDY DESIGN AND METHODS:  A total of 168 blood samples from Caucasian individuals were studied because of weak D expression and/or anti‐D production. Serologic analysis and molecular analysis were performed.

RESULTS:  In total, 70 partial D and 62 weak D were identified. Among weak D samples, 30 weak D Type 1 and 21 weak D Type 2 alleles were found. Five new alleles were characterized carrying 399G > T, 680T > C, 833G > A, 851C > T, and 1015G > A, respectively. According to previous studies, antigen density was up to 500 for weak D Type 1 and 2, except when there was a dCe haplotype in trans. Antigen density was below 400 antigens per red blood cell for the new variants and most other weak D variants.

CONCLUSION:  These results provide molecular characterization of five new D variants. They also suggest that it would be advantageous to develop in routine laboratories weak D Type 1 and 2 genotyping for serologically depressed D antigen. It will help to avoid wasting of D– red blood cell units because carriers may safely receive D+ units.
The Aged Are Family Members
Authors: SPARK GERALDINE M. , BRODY ELAINE M.
Published: August 2004

Research reveals that the notion of the aged being abandoned or dumped by families is a myth. In general close ties and mutually responsible behavior continue. For those engaged in family treatment, older families and intergenerational relationships are a clinical frontier. Practitioners have the opportunity to experience and observe, in depth, the emotional quality and meaning of intergenerational relations. Older family members may play important roles in the family dynamics. It is hypothesized that their inclusion when appropriate in the treatment of younger families can be a preventive measure to forestall cyclical repetition of pathological relationship patterns. Just as family therapists are committed to the premise that many nuclear families are capable of psychological growth and change, they must become aware that aged family members have similar capacities. If intergenerational relationships are modified then family members in all the generations could be benefited.
A System of Notation of Dyadic Interaction
Authors: RAVICH ROBERT A.
Published: August 2004

The necessity of organizing the large quantity of data derived from the use of the Ravich Interpersonal Game‐Test (RIG/T) (1) has led to the development of a system of notation of two‐person interaction.
Child Participation in Family Therapy
Authors: ACKERMAN NATHAN W.
Published: August 2004

The full involvement of children, particularly those of younger ages, in family therapy presents a personal and professional challenge to the therapist. Out of his own needs he may favor involvement with one or another generation rather than with the complete three generation family. This issue is discussed and suggestions for therapeutic use of younger children are presented.
Non‐Verbal Communication and Marital Satisfaction
Authors: KAHN MALCOLM
Published: August 2004

Twenty‐one college couples were identified as maritally satisfied and 21 couples as maritally dissatisfied by the Locke‐Wallace Marital Adjustment Scale. The Marital Communication Scale (MCS), a new behavioral measure of accuracy of marital non‐verbal communication, and the Primary Communication Inventory (PCI), a self‐report measure, were administered to each couple. The results indicate a relationship between marital satisfaction and accuracy of non‐verbal communication as assessed by both measures. The commonality of the two measures was found to be limited, however.
Two Families: The Origins of a Therapeutic Crisis
Authors: ERLICH‐AMITAI HERBERT S. , BLOCH DONALD A. , CAMBOR C. GLENN
Published: August 2004

The treatment by individual and family therapy of a hospitalized young woman is presented as it reflects the historical and current family dynamics of the patient and her individual psychotherapist. The contribution of these factors to a therapeutic crisis is discussed.
T. S. Eliot's The Family Reunion—“Schizophrenia” Reconsidered
Authors: SANDER FRED M.
Published: August 2004

T. S. Eliot's play, The Family Reunion (4), can be interpreted as a representation of a “schizophrenic” and his family. As such it illustrates some of the clinical insights of both individual psychiatry and family psychiatry. This paper will discuss the play from a clinical vantage point and conclude with a re‐consideration of the concept of schizophrenia.
Patterns of Interaction in Families with Low Adjusted, High Adjusted, and Mentally Retarded Members
Authors: O'CONNOR WILLIAM A. , STACHOWIAK JAMES
Published: August 2004

Family interactions were compared in three groups: families with a low adjusted child prior to formal clinic contact (LA), with a high adjusted child (HA), and with a retarded child (RM). Nine measures were utilized, described as: adaptation, stability, productivity, specificity, overt power, conflict, cohesion, and emotionality. Data suggested a failure of cohesion in the LA group, but many clinic‐family stereotypes were supported. HA families showed high cohesion, but also high conflict. RM families showed cohesion, but many “auxiliary” control features, such as assigning “youngest sib” role to the handicapped child.
The “Shadow‐of‐Death” and Its Implications in Four Families, Each with a Hospitalized Schizophrenic Member
Authors: WELLDON RONALD M. C.
Published: August 2004

This paper summarizes the salient points from tape recordings of conjoint sessions with four families, each with a hospitalized schizophrenic member carrying a poor prognosis. As the sessions progressed, a profound and overwhelming sense of frustration, foreboding, doom and despair emerged, as if the family were attempting to preserve what seemed destined to die.

Each family as a whole was involved in what can best be described as a vicious circle of displaced and distorted mourning for a dead family member. This had deep and unresolved emotional significance for one or other parent. This same parent was also more obviously involved with the schizophrenic child, whose own symbolic family role included both being protected from anything in life carrying the possibility of death and distracting others from the source of this “shadow‐of‐death.”
The Marriage Contract
Authors: Sager Clifford J. , Kaplan Helen S. , Gundlach Ralph H. , Kremer Malvina , Lenz Rosa , Royce Jack R.
Published: August 2004

This article is intended to serve as an introduction to the concept of the marriage contract, which has proved to be a useful clinical tool for clarification and treatment of troubled marriages. Transactional as well as intrapsychic factors are important aspects of marital dynamics. The contract concept employs both these behavioral parameters and facilitates therapeutic intervention at both levels.
Perceived Parental Attitudes and Family Concepts of Disturbed Adolescents, Normal Siblings and Normal Controls
Authors: VAN DER VEEN FERDINAND , NOVAK ARTHUR L.
Published: August 2004

This study tested the hypotheses that disturbed adolescents perceive lower parental attitudes (positive regard, empathic understanding, genuineness and unconditional regard) than are perceived by their normal siblings and normal controls; that normal siblings do not differ from normal controls on these variables; that levels of perceived attitudes are positively related to family concept measures of adjustment and satisfaction; and that attitudes perceived in one parent are positively associated with those perceived in the other. The hypotheses were substantially confirmed. In contrast to both normal groups, the disturbed adolescents failed to show positive relationships between maternal attitudes and the family concept measures and between perceived paternal and maternal attitudes.
The Marriage of Families: Cross‐Generational Complementarity
Authors: NAPIER AUGUSTUS Y.
Published: August 2004

Marriage is often characterized as a beginning, a fresh start. This paper presents the results of an exploratory study of two young “normal” couples and the family of origin of each partner. An attempt is made to examine the “emergent” marriage in the context of its familial origins with special emphasis on cross‐generational complementarily.
Living Space in an Urban Ghetto
Authors: SCHEFLEN ALBERT E.
Published: August 2004

In this paper I will outline the idea of human territoriality and then describe some territorial arrangements and behaviors in the households we have studied.

The environment of people is prestructured socially and temporally. For two years our research team has been studying the prestructured living spaces and the territorial behavior of urban people in a central Bronx ghetto. We have conducted interviews in about 1800 households, photographically surveyed space layouts in 35, and videotaped space usage and territorial behavior intensively in six. In the main, our data is about Puerto Ricans and Afro‐Americans; we have a little data about Italian‐Americans, but the Jewish and old British American families have moved out of the East Tremont area.
Process and Outcome in Conjoint Family Therapy
Authors: POSTNER ROSLYN SPECTOR , GUTTMAN HERTA A. , SIGAL JOHN J. , EPSTEIN NATHAN B. , RAKOFF VIVIAN M.
Published: August 2004

Forty‐nine coded twenty‐minute transcript segments sampled at six‐week intervals from the conjoint treatment of eleven families were examined. Coding procedures tapped both participation and affective expression (Emergency, Welfare, and Neutral) of family members and the quantity, direction, and quality of therapists' interventions. The families were assigned to two outcome groups on the basis of change scores in four areas (Overall; Affective Involvement; Affective Communication and Affective Expression) derived from the independent ratings of pre and post‐therapy interviews by three judges (73 percent agreement). A two‐way analysis of variance applied to the Good and Poor Outcome group coding data indicated an increase in Welfare feelings, a sharp decrease in Neutral speech paralleled by an initial rise then leveling off of Emergency. For any given therapist‐family unit, therapist's output remained within a unique range, the level of which rose gradually only in the Good Outcome group. Therapists focused increasingly on only one family member, usually a parent, the parent initially most talkative. A Good Outcome resulted when the father was initially the more vocal parent, a Poor Outcome when mother outtalked father. The Drive‐Interpretation ratio decreased as therapy progressed. The initial level of this ratio was positively related to outcome and inversely to drop‐out rate.
Communicational Styles and Interaction of Alcoholics and Their Wives
Authors: GORAD STEPHEN L.
Published: August 2004

The following hypotheses, derived from an interpersonal‐interactional theory of alcoholism were investigated: (1) The alcoholic uses a style of communication characterized by responsibility avoidance, when interacting with his wife; (2) The wife of the alcoholic uses a more direct, responsibility‐accepting style of communication than her husband, when interacting with him; (3) The interaction between an alcoholic and his wife is marked by (a) an inability to function as a unit for mutual benefit, and (b) rigidity of complementarity and/or escalation of symmetry. These hypotheses were tested by placing twenty married couples with alcoholic husbands and twenty normal control couples in an interactional game‐playing situation. Hypotheses 1, 2, and 3a were confirmed. It was found that alcoholic couples use the escalation of symmetry pattern (hypothesis 3b). Additional findings on competition, dominance, and interactional rigidity are discussed.
Immunohistochemical assessment of extracellular matrix components in syndrome and non‐syndrome odontogenic keratocysts
Authors: Amorim RFB , Godoy GP , Galvão HC , Souza LB , Freitas RA
Published: August 2004

Objective:  Investigate the immunohistochemical distribution of fibronectin, tenascin, laminin and collagen IV in syndrome (SOKC) and non‐syndrome odontogenic keratocysts (NSOKC).

Materials and methods:  Ten cases of SOKC and five of NSOKC were selected and streptoavidin‐biotin technique was applied. The specimens were analyzed taking into account the following evaluation parameters: presence, continuity and thickness in the basement membrane and intensity, distribution and association with inflammatory cells in the cyst wall.

Results:  Differences could be detected regarding tenascin, fibronectin and collagen IV between the SOKC and NSOKC. Tenascin was present in all cases along the basement membrane in SOKC and in five cases of NSOKC predominated negative areas. Furthermore, tenascin distribution was focal in the cyst wall in SOKC whereas in NSOKC it was diffuse. Concerning fibronectin, it was detected as a discontinuous band when present in SOCK and as a continuous band in NSOKC. Collagen IV was not present in the majority of the cases in SOKC. Negative areas for laminin predominated in the basement membrane in both groups.

Conclusions:  These findings show differences between the immunohistochemical expression of tenascin, fibronectin and collagen IV which might indicate a more aggressive biological behavior of SOKC as compared with NSOKC.
Effect of amine fluoride/stannous fluoride toothpaste and mouthrinse on dental plaque accumulation and gingival health
Authors: Madléna M , Dombi C , Gintner Z , Bánóczy J
Published: August 2004

Objective:  The aim was to investigate the influence of amine fluoride (AmF)/stannous fluoride (SnF2) containing toothpaste and mouthrinse on plaque accumulation and gingival health of young adults after 4 weeks use.

Subject and methods:  Forty‐two young adults (mean age: 28.33 ± 7.19 years) were examined for the Plaque Index (PI; Silness and Löe, 1964) and Gingival Index (GI; Löe and Silness, 1963) scores, and divided randomly into two groups. Both groups used AmF/SnF2 containing toothpaste twice a day for 3 min toothbrushing, and one group after toothbrushing rinsed with AmF/SnF2 containing mouthrinse for 30 s. After 4 weeks the probands were re‐examined.

Results:  Statistically significant decrease in dental plaque (PI) and gingival (GI) index values were found at the end of the study. The reduction of PI and GI values was significant in all groups but it was higher in the combined (toothpaste + mouthrinsing) group, than using toothpaste only.

Conclusion:  The regular combined use of AmF/SnF2 toothpaste and mouthrinse was more effective in the reduction of plaque accumulation and maintenance of gingival health than the toothpaste alone.
Expression of integrin subunits α2, α3, α5, αv, β1, β3 and β4 in different histological types of ameloblastoma compared with dental germ, dental lamina and adult lining epithelium
Authors: Modolo F , Martins MT , Loducca SVL , De Araújo VC
Published: August 2004

Objective:  To analyze integrin expression and distribution in different histological types of ameloblastoma, compared with dental germ, dental lamina and adult lining epithelium.

Materials and methods:  Three‐micrometer sections from paraffin‐embedded specimens were evaluated employing a streptavidin–biotin immunohistochemical method and anti‐integrin α2, α3, α5, αv, β1, β3 and β4 antibodies.

Results:  All integrins were present in all specimens, exhibiting different patterns. In follicular ameloblastoma, the integrin staining was stronger in the periphery while integrin α2 was not present in the central cells. Acanthomatous ameloblastoma showed a similar pattern, with positive staining for integrins α3, α5, αv, β1 and β4 in the metaplastic cells. In the unicystic, integrin staining was uniform except for integrins α5 and β3 which showed weaker staining in the upper layers. In the plexiform ameloblastoma, dental germ and lamina integrin staining was uniform. In the adult lining epithelium, staining for integrins α2, α5 and β4 was confined to the basal layer, while integrins αv and β3 were present in the basal and parabasal, with integrins α3 and β1 in the upper layers.

Conclusion:  Acanthomatous, follicular and unicystic ameloblastomas showed integrin staining patterns similar to the adult lining epithelium while the plexiform ameloblastoma was similar to the dental germ and lamina.
Solubility properties of human tooth mineral and pathogenesis of dental caries
Authors: Aoba T
Published: August 2004

Dental research over the last century has advanced our understanding of the etiology and pathogenesis of caries lesions. Increasing knowledge of the dynamic demineralization/remineralization processes has led to the current consensus that bacteria‐mediated tooth destruction can be arrested or even to some degree reversed by adopting fluoride and other preventive measures without using restorative materials. Our experimental approach provided new insight into the stoichiometries and solubility properties of human enamel and dentin mineral. The determination of the solubility product constant on the basis of the stoichiometric model (Ca)5·x(Mg)q(Na)u(HPO4)v(CO3)w(PO4)3·y(OH,F)1·z, verifies the difference in their solubility properties, supporting the phase transformation between tooth mineral and calcium phosphates in a wide range of fluid compositions as found in the oral environment. Further refinement of the stoichiometry and solubility parameters is essential to assess quantitatively the driving force for de‐ and remineralization of enamel and dentin in the oral fluid environment. Prediction of the effects of a combination of inhibitors and accelerator(s) on remineralization kinetics is also required. In order to develop devices efficient for optimizing remineralization in the lesion body, it is a critical question how, and to what extent, fluoride can compensate for the activity of any inhibitors in the mineralizing media.
Following in Einstein's Footsteps: Teaching the Photoelectric Effect
Authors: Calvin Scott
Published: August 2004

Five years ago when I was asked to develop a module on quantum physics for a new course,1 I decided to see if students could reproduce some of the reasoning that won Einstein his Nobel Prize. The students were in the third semester of a four-semester sequence emphasizing guided discovery, graphical analysis, and scientific communication. Most had weak high school physics backgrounds and had shown little evidence of remembering the concepts they had been exposed to at that level. The students were accustomed to working in groups of three to five for two-hour in-class workshops. They had not studied concepts related to light, optics, or electromagnetism in the course to that point. Thus, I gave them a workshop that presented a description of the photoelectric effect experiment at a schematic level (light of various colors hits a metal, electrons come off, the number of electrons and the kinetic energy per electron are measured), and a data table consisting of the qualitative color of the incident light, the intensity of the light, the number of electrons, and the kinetic energy per electron. The workshop asked them to graph the data in whatever way they felt appropriate, and to suggest a model of light that could explain the results.
Making ‘Internal Thermal Energy’ Visible
Authors: Zou Xueli
Published: August 2004

In a 1992 paper published in this journal, Uri Ganiel1 described a pair of model carts used to demonstrate elastic and inelastic collisions. The wooden carts had low-friction wheels and a steel-strip bumper on one end. On one of the carts, a number of brass washers were rigidly mounted in vertical stacks to a wooden framework. The other cart was similar except that the washers were tied to rubber bands that were stretched horizontally and diagonally across the framework. When the first cart was rolled into a wall it bounced off with only a small reduction in speed (“elastic” collision). The second cart, on the other hand, was found to come nearly to a complete stop upon colliding with the wall (“inelastic” collision). Following the instructions given in Ganiel's paper, I built a pair of carts and demonstrated them to introductory-level physics students at a large public university. It was interesting to find that many students were distracted by the different-looking structures of the two model carts.2 They thought the different distributions of washers between the carts resulted in the rubber-band cart bouncing back a significantly shorter distance than the rigid-rod one after they both collided with a wall at the same initial speed. Apparently, the students had difficulties in understanding the collisions and used surface features to reason about them. To avoid this superficial distraction and to help students visualize easily “where the kinetic energy goes in an inelastic collision,” I modified the rigid-rod cart to have washers fixed on hollow aluminum rods mounted at four different levels horizontally and diagonally (see Fig. 1). The new pair of the model carts look very similar to each other: They have the same bumpers, same wheels, same distributions of washers, and same masses.
Stellar Inquiry
Authors: Slater Timothy F.
Published: August 2004

The NRC National Science Education Standards (NSES) clearly indicate that concepts should be taught from a perspective of student-centered inquiry. For some concepts, this inquiry-based strategy is much easier said than actually done. For me personally, one of the most difficult concepts to teach in Earth and space science that is explicitly stated in the NSES, without resorting to rote student memorization, is the life cycles of stars. Developed through considerable trial-and-error, I would like to share a student-centered, learning-cycle approach to teaching star life cycles.
Illustrating Electric Circuit Concepts with the Glitter Circuit
Authors: Pfister Hans
Published: August 2004

Many beginning physics students have a harder time understanding basic concepts of electric circuits than understanding basic mechanics concepts. This is likely due to the fact that we cannot see electric charge carriers (electrons) move through an electric wire. It is thus the responsibility of the physics instructor to introduce his/her students to a variety of electric circuit models that will enable those students encountering circuits for the first time to come up with their own coherent mental picture of current flow in an electric circuit. Electric circuit analogs might prove helpful in this endeavor.
A Strange Direction for Static Friction
Authors: Keeports David
Published: August 2004

Except at the Earth's poles and at the equator, a box on a horizontal surface cannot remain at rest relative to the surface unless a very small static friction force acts upon the box. I demonstrate here that in the Northern Hemisphere, the required static friction is in the counterintuitive direction of south to north.
The Metal Detector and Faraday's Law
Authors: McNeil J. A.
Published: August 2004

Electromagnetism has proven a notoriously difficult subject for beginning physics and engineering students. When simultaneously exercising their newly acquired calculus skills on abstract electromagnetism concepts, these students often lose the physics in the mathematical formalism. One way we have addressed this problem is by including engineering-style design and fabrication activities in the laboratory portion of the course. In addition to providing concrete examples of the electromagnetic concepts under study, the integration of mathematics and physics concepts in the design activities can significantly raise the level of student interest, increase the ownership of their learning, and ultimately improve learning and retention.
The Kodak One-Time-Use Flash Camera
Authors: Carlson John
Published: August 2004

When the subject of capacitors is brought up, students often question how they are used in common everyday life. One excellent example is their use in camera flash units. The flash needs both high voltage and high current for a very short period of time, and a capacitor can deliver both. The Kodak one-time-use camera offers a unique opportunity to illustrate not only how a capacitor is used in a practical circuit, but also how a 1.5-V battery can charge the capacitor to over 300 V using a dc circuit with a transformer.
IS MASS QUANTIZED?
Authors: WESSON PAUL S.
Published: August 2004

The cosmological constant combined with Planck's constant and the speed of light implies a quantum of mass of approximately 2×10-65 g . This follows either from a generic dimensional analysis, or from a specific analysis where the cosmological constant appears in 4D spacetime as the result of a dimensional reduction from higher-dimensional relativity (such as 5D induced-matter and membrane theory). In the latter type of theory, all the particles in the universe can be in higher-dimensional contact.
THE FORMATION AND THE INNER STRUCTURE OF THE EARTH BY N-BODY SIMULATION
Authors: PAVLOV ANDREI
Published: August 2004

A mechanism of formation of a planet from a gaseous cloud and dust is proposed. The particles of the clouds are combined into clusters and the gravitational contraction of the system is modeled using central gravitational field. Initially the clusters are randomly distributed in the space, and during the contraction process they form hollow spherical layers. The thermodynamic approach considers each cluster as a volume comprising an initial number of the particles to give the temperature of the layers. This method has been used to model the formation of the Earth at early stages. Our results demonstrate that the gravitational contraction leads to quantization of the structure and formation of spherical shells. Particularly, the Earth consists of at least three spherical layers of high density.
ISO Spectroscopy of Gas and Dust: From Molecular Clouds to Protoplanetary Disks
Authors: van Dishoeck Ewine F.
Published: August 2004

▪ Abstract  Observations of interstellar gas-phase and solid-state species in the 2.4–200 μm range obtained with the spectrometers on board the Infrared Space Observatory (ISO) are reviewed. Lines and bands caused by ices, polycyclic aromatic hydrocarbons, silicates, and gas-phase atoms and molecules (in particular H2, CO, H2O, OH, and CO2) are summarized and their diagnostic capabilities illustrated. The results are discussed in the context of the physical and chemical evolution of star-forming regions, including photon-dominated regions, shocks, protostellar envelopes, and disks around young stars.
Neutron Star Cooling
Authors: Yakovlev D.G. , Pethick C.J.
Published: August 2004

▪ Abstract  Observation of cooling neutron stars can potentially provide information about the states of matter at supernuclear densities. We review physical properties important for cooling such as neutrino emission processes and superfluidity in the stellar interior, surface envelopes of light elements owing to accretion of matter, and strong surface magnetic fields. The neutrino processes include the modified Urca process and the direct Urca process for nucleons and exotic states of matter, such as a pion condensate, kaon condensate, or quark matter. The dependence of theoretical cooling curves on physical input and observations of thermal radiation from isolated neutron stars are described. The comparison of observation and theory leads to a unified interpretation in terms of three characteristic types of neutron stars: high-mass stars, which cool primarily by some version of the direct Urca process; low-mass stars, which cool via slower processes; and medium-mass stars, which have an intermediate behavior. The related problem of thermal states of transiently accreting neutron stars with deep crustal burning of accreted matter is discussed in connection with observations of soft X-ray transients. Observations imply that some stars cool more rapidly than can be explained on the basis of nonsuperfluid neutron star models cooling via the modified Urca process, whereas other star cool less rapidly. We describe possible theoretical models that are consistent with observations.
My Cruise Through the World of Astronomy
Authors: Blaauw Adriaan
Published: August 2004

▪ Abstract  I was born in 1914 in Amsterdam. I grew up there, filling my teenage years with activities as an amateur astronomer. I later studied at Leiden University and volunteered at Leiden Observatory. From 1938 to 1945, I was assistant at the Kapteyn Institute in Groningen, including during the war years 1940–1945, returning to Leiden in October 1945. After prolonged stays at Yerkes Observatory in 1947–1948 and 1952, and participation in Leiden's astrometric Kenya expedition in 1949–1950, I became associate professor at Yerkes Observatory in the fall of 1953. In 1957, I returned to the Kapteyn Institute and soon became involved in the creation of ESO, of which I became scientific director in 1968 and director general from 1970 to 1974. In 1975, I joined Leiden Observatory again, staying until my retirement in 1981, and since then I have enjoyed the hospitality of the Kapteyn Institute. I was president of the IAU from 1976 to 1979. From 1982 to 1989, I was chairman of the Scientific Programs Selection Committee for the European Space Agency's satellite, Hipparcos. My principal research interests have been in galactic structure and star formation, with emphasis on stellar associations. In addition to my astronomical interests, I have researched and published on Dutch village history.
Eros and Faint Red Galaxies
Authors: McCarthy Patrick J.
Published: August 2004

▪ Abstract  This chapter reviews the properties of faint IR-selected field galaxies and the extremely red color-selected populations in particular. These populations are a mix of passively evolving stellar systems and heavily obscured star-forming galaxies. The star-forming component appears to constitute 20–50% of the population depending on the magnitude and color cuts employed. The remaining objects are a mix of passively evolving ellipticals and early-type disk galaxies. The passively evolving red galaxies are strongly clustered in space and are likely the high-mass high-luminosity end of the elliptical galaxy progenitor population at redshifts between one and two. These galaxies have masses and space densities that appear to be in conflict with late-forming hierarchical galaxy-formation models. The red galaxies appear to be a population that is distinct from the moderately star-forming Lyman-Break galaxies but may be related to the starburst population at z > 2 seen in deep submillimeter surveys.
Chronic Inflammation and Impaired Coronary Vasoreactivity in Patients With Coronary Risk Factors
Authors: Schindler Thomas H. , Nitzsche Egbert U. , Olschewski Manfred , Magosaki Nobuhisa , Mix Michael , Prior John O. , Facta Alvaro D. , Solzbach Ulrich , Just Hanjoerg , Schelbert Heinrich R.
Published: August 2004

Background—

The goal of this study was to examine a possible association between systemic microinflammation, as reflected by C-reactive protein (CRP) serum levels, and coronary vasomotion in patients with coronary risk factors but with angiographically normal coronary arteries.

Methods and Results—

Coronary vasomotor function was studied in response to cold pressor testing (CPT) in 71 patients with normal angiograms. In all patients, CPT-induced changes in epicardial luminal area (LA; mm
2
) were assessed with quantitative angiography. Within 20 days, myocardial blood flow (MBF) responses to CPT were measured (mL · g
−1
· min
−1
) noninvasively with
13
N-ammonia and PET imaging. The CPT-induced mean changes in LA and in MBF in patients with elevated CRP (≥0.5 mg/dL) were significantly impaired compared with patients presenting with CRP levels within normal range (<0.5 mg/dL) (ΔLA, −1.09±0.86 versus 0.45±0.63 mm
2
; ΔMBF, 0.06±0.18 versus 0.44±0.31 mL · g
−1
· min
−1
;
P
<0.0001, respectively). Coronary LA changes and MBF responses to CPT were inversely correlated with CRP serum levels (
r
=−0.84 and
r
=−0.63;
P
<0.0001). Lastly, regression analysis revealed a significant correlation between the changes in LA and MBF during CPT for patients with elevated CRP levels and those for patients with normal CRP levels (
r
=0.56 and
r
=0.66;
P
<0.001).

Conclusions—

These findings suggest a direct association between systemic microinflammation and altered coronary vasomotor function of both the epicardial conductance and the arteriolar resistance vessels.