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Medial preoptic area interactions with the nucleus accumbens-ventral pallidum circuit and maternal behavior in rats.

Several experiments explored the roles of nucleus accumbens (NA), ventral pallidum (VP) and medial preoptic area (MPOA) in the regulation of maternal behavior in rats. A preliminary experiment found that bilateral radiofrequency lesions of medial NA did not disrupt maternal behavior. Experiment 1 found that bilateral infusions of muscimol into VP, but not into medial NA, reversibly disrupted maternal behavior. Experiment 2 found that unilateral muscimol injections into VP disrupted maternal behavior to a greater extent when paired with a contralateral N-methyl-d-aspartic acid (NMDA) MPOA lesion than when paired with a sham MPOA lesion. Experiment 3 showed that a unilateral NMDA MPOA lesion paired with a contralateral NMDA VP lesion (Contra group) disrupted maternal behavior to a much greater extent than did sham NMLA lesions or NMDA lesions of MPOA and VP ipsilateral to one another. Experiment 3 focused on the specificity of the maternal behavior disruptions and found that the primary maternal deficit in the Contra females was a severe deficit in retrieval behavior. Importantly, these females showed normal hoarding behavior, home cage activity, and elevated plus maze activity. Experiment 3 used Neu N immunohistochemistry to define the extent of MPOA and VP excitotoxic lesions. It is hypothesized that MPOA acts to facilitate the active components of maternal behavior by inhibiting NA, which then releases VP from GABAergic inhibition, and such disinhibition of VP allows pup stimuli to trigger appropriate maternal responses.

Analysis of Variance↗

Medicare payment changes and nursing home quality: effects on long-stay residents.

The Balanced Budget Act of 1997 dramatically changed the way that Medicare pays skilled nursing facilities, providing a natural experiment in nursing home behavior. Medicare payment policy (directed at short-stay residents) may have affected outcomes for long-stay, chronic-care residents if services for these residents were subsidized through cost-shifting prior to implementation of Medicare prospective payment for nursing homes. We link changes in both the form and level of Medicare payment at the facility level with changes in resident-level quality, as represented by pressure sores and urinary tract infections in Minimum Data Set (MDS) assessments. Results show that long-stay residents experienced increased adverse outcomes with the elimination of Medicare cost reimbursement.

Aged↗

Case-mix payment for nursing home care: lessons from Maryland.

Even before Medicare adopted case-based payments for hospitals, some state Medicaid programs employed case-mix payment systems for nursing home care. Their purpose was less to promote cost containment than to improve access to nursing homes for the most costly patients. This paper evaluates one such system, adopted by the state of Maryland in 1983 as part of an overall reimbursement reform. Using data on nursing home patient characteristics, costs, and staffing, as well as interviews with officials and various providers of care, the article shows that Maryland's system was successful in shifting nursing home service away from light-care and toward heavy-care patients. Furthermore, the shift occurred without inducing readily measurable declines in quality of care and with little additional administrative cost (partly because the state built its case-mix system on preexisting patient review activities). Although states could learn from and improve upon Maryland's experience--most notably in offering incentives to improve quality of care and in targeting community care on the light-care patients that nursing homes become less willing to serve--Maryland demonstrates that case-mix payment can change nursing home behavior in desired directions without substantial negative consequences.

Activities of Daily Living↗

The use of teacher checklists to identify children at risk for later behavioral and emotional problems.

Measures of child behavior based on teacher checklists have been shown to be reliable and valid indicators of a child's current school functioning. Such measures, however, are not very accurate predictors of behavior in other settings, or of the development of future behavior problems; they should not be used to label a child as "high risk." The primary care physician could help the teacher decide which children to refer for more thorough evaluation by providing the teacher with information on the child's development and neurologic status, home behavior, and family situation. Follow-up studies suggest that many behavioral disturbances seen in pre-school settings are transient situational disturbances that could be adequately managed through use of behavior modification techniques or simply through the passage of time.

Affective Symptoms↗

Reactions of adolescents following hospitalization for acute conditions.

Examination of the behaviors of 85 hospitalized adolescents during a 28-day summer period following discharge from two acute care hospitals was undertaken. A control group of 63 nonhospitalized adolescents was used. Self-esteem and body attitude measures were administered at 3 and 28 days following discharge, and parents provided information on adolescent in-home behavior. Positive self-esteem, body attitude scores, and personal comments of hospitalized adolescents suggest aspects of psychological benefit from short-term hospitalization.

Adolescent↗

Lymphocyte homing and clinical behavior of non-Hodgkin's lymphoma.

Lymphocyte homing receptors (HRs) defined by Hermes antibodies (anti-CD44) and lymphocyte function associated antigen-1 (LFA-1, CD11a/CD18) are involved in lymphocyte binding to endothelial cells of high endothelial venules (HEVs) at sites where lymphocytes exit the blood. Their expression was correlated to the clinical behavior of 245 non-Hodgkin's lymphomas followed up for the median of 87 mo after the diagnosis. Lymphomas that showed no or weak staining intensity for HRs were more often of stage I (P = 0.005), disseminated less frequently hematogenously (P = 0.003), and had more favorable prognosis than lymphomas with intensive staining for HRs (P less than 0.0001) despite that they were more often histologically of high grade malignancy (P = 0.002). Expression of LFA-1 beta chain (CD18) did not correlate significantly with stage or survival, but had prognostic value in a subgroup of HR expression negative lymphomas (P = 0.03). HR staining intensity was an independent prognostic factor in a multivariate analysis. These findings indicate that Hermes/CD44 molecule is associated to the determination of the metastatic potential and prognosis of non-Hodgkin's lymphomas. They also reveal a new entity among non-Hodgkin's lymphomas, because lymphomas that express low levels of HR have favorable prognosis despite their often highly malignant histological appearance.

Adolescent↗

Altered migration of gut-derived T lymphocytes after activation with concanavalin A.

Although activation of lymphocytes is known to be associated with profound changes in homing behavior, it remains unclear how activation alters migration of gut-derived lymphocytes in lymphoid and nonlymphoid organs. The objectives of this study were 1) to compare migration of naive and concanavalin A (ConA)-activated T lymphocytes into the gut mucosa, spleen, and liver and 2) to define the role of specific adhesion molecules in this homing process. Fluorescently labeled T lymphocytes collected from rat intestinal lymph were injected into the jugular vein, and the kinetics of appearance of the infused lymphocytes were monitored in ileal Peyer's patches, spleen, and liver. The migration of naive and ConA-activated T lymphocytes into microvessels were compared using an intravital microscope. ConA stimulation significantly increased the rolling velocity of T lymphocytes in postcapillary venules of Peyer's patches, and ConA-stimulated lymphocytes exhibited a loss of the selective adherence properties in Peyer's patches that is normally observed with naive T cells. ConA activation also suppressed the accumulation of T cells in the spleen. On the other hand, the adherence of T cells to hepatic sinusoidal endothelium was significantly increased after ConA activation, especially in the periportal area, and this increase was attenuated by an anti-intercellular adhesion molecule (ICAM)-1 antibody. Flow cytometry analysis revealed a decline in L-selectin expression and an increase in CD11a expression and ICAM-1 on the surface of ConA-treated T cells. In conclusion, activation of gut-derived T lymphocytes with ConA significantly alters their migration path, with a diminished localization to Peyer's patches and spleen and a preferential accumulation in hepatic sinusoids. This altered migration pattern likely results from changes in the expression of leukocyte adhesion molecules such as L-selectin and CD11a.

Animals↗

Differential expression of homing-associated adhesion molecules by T cell subsets in man.

The ability of lymphocyte populations to recognize and bind high endothelial venules during homing into lymphoid tissues and sites of chronic inflammation is critically dependent on their expression of certain homing-associated adhesion molecules known as homing receptors (HR). In animal models, certain lymphocyte populations, particularly subsets of memory or previously activated lymphocytes, demonstrate tissue-selective homing behavior, and it has been hypothesized that differential expression of HR accounts for this selective migration. In this study, we analyzed expression of human HR--the Dreg 56/Leu 8-defined peripheral lymph node (PLN) HR (also known as LECAM-1), H-CAM (CD44), and alpha 4-integrins (CD49d; VLA-4)--among subsets of thymocytes and peripheral blood T cells to identify populations with differential homing potential. In the thymus, these three HR classes are differentially regulated relative to phenotypically defined maturational stages, but are all expressed on the mature, surface CD3high subset. In the peripheral blood, virgin T cells (LFA-3/CD58low) show uniform high expression of the PLN HR, uniform relatively low expression of H-CAM and alpha 4-integrin, and lack markers of tissue association--the mucosal and cutaneous lymphocyte associated Ag (MLA and CLA Ags) defined by mAb Ber ACT8 and HECA-452, respectively. In contrast, circulating memory T cells (LFA-3/CD58high) are bimodal with respect to PLN HR expression, show uniform high expression of H-CAM and alpha 4-integrin, and contain essentially all the CLA and MLA Ag-bearing T cells. The circulating skin-associated T cell subset (CLA Ag+; 10 to 15% of total T cells) is predominantly PLN HR+, and shows high levels of both the alpha 4- and beta 1-integrin chains. The distinct mucosa-associated T cell subset (MLA Ag+; 1 to 3% of peripheral blood T cells) is predominantly PLN HR-; and is alpha 4high, but beta 1low. These findings indicate the independent regulation of homing-associated adhesion molecules among populations of memory/previously activated T cells, and suggest that the expression patterns of these molecules contribute to, or perhaps determine, the tissue distribution of these subsets.

Adult↗

Homing of fluorescently labeled murine hematopoietic stem cells.

PKH-26 was used as a viable fluorescent membrane stain for murine hematopoietic stem cells. The presence of the dye on the cells was shown not to interfere with their ability to form day-8 and -12 spleen colonies in lethally irradiated mice. To study their in vivo homing behavior in detail, 10(4) labeled cells from a population enriched for CFU-S were injected intravenously into nonirradiated mice and into mice irradiated 3 hours previously. At 17, 41, and 65 hours after injection, the numbers of labeled cells per organ were quantified using the specialty developed flow cytometric fluorescence hypercompensation procedure for the detection of rare events, which allows a detection sensitivity of 1 per 10(6). Spleen homing in irradiated and nonirradiated mice was virtually identical, whereas homing to nonirradiated bone marrow was 2.5 times higher than to irradiated bone marrow. This indicates a different homing mechanism for spleen and bone marrow. The results of this direct homing assay were placed in perspective with results of indirect homing studies from the literature, introducing a new "h-factor." From the CFU-S data, putative specific enrichment factors for spleen-specific and bone marrow-specific homing were derived. Examination of the fluorescence intensity distribution among the labeled cell population indicated that virtually all cells started to proliferate rapidly after injection into both irradiated and nonirradiated animals. This indicates that specific signals from stromal elements in the stem cell niches are needed to keep the cells quiescent and that the majority of the transplanted stem cells do not home to such niches. The potential use of PKH-26 for in vivo characterization of stem cell niches is discussed.

Animals↗

Antigen-dependent transgene expression in kidney transplantation: a novel approach using gene-engineered T lymphocytes.

So far, gene therapy in transplantation mainly focuses on the expression of therapeutic proteins in the graft itself. Insufficient transfection and inflammatory responses that are due to the immunogenicity of multiple vector systems are often limiting factors in these approaches. The potential of genetically modified T lymphocytes was investigated as a delivery system for therapeutic transgenes to transplanted organs as a way to circumvent immunogenicity and efficiency problems in a rat transplant model. Gene-engineering of alloantigen-specific rat T cell lines was performed by using a Moloney murine leukemia virus (MoMuLV)-based enhanced green fluorescence protein (EGFP) encoding retroviral transduction system. The ex vivo gene-modified lymphocytes were adoptively transferred into syngeneic rats carrying allogeneic, syngeneic, or third party kidneys. Homing behavior, activation level, and transgene expression of the adoptively given cells were monitored. The T(EGFP) lymphocytes infiltrated the transplanted kidneys in an antigen-specific manner. High numbers of alloantigen-specific T lymphocytes accumulated exclusively in allografts but not in syngeneic or third party grafts. Flow cytometric analysis revealed that only T(EGFP) lymphocytes found in allografts had an activated phenotype that resulted in higher transgene expression. Alloantigen-specific homing, activation, and transgene expression are important prerequisites for the guarantee of localized delivery and expression of transgenic proteins by gene-engineered T lymphocytes. Antigen-specific gene-targeting strategies using ex vivo modified T lymphocytes with donor specificity are a novel approach to the delivery of therapeutic transgenes in transplantation.

Adoptive Transfer↗

Determinants of adherence to methylphenidate and the impact of poor adherence on maternal and family measures.

OBJECTIVE: The aim of this study was to examine the association between adherence to immediate-release methylphenidate (IR MPH) and maternal psychological distress, parenting style, parent- child relationship, and perceived family support. METHODS: The sample consisted of 307 children with attention-deficit hyperactivity disorder (ADHD) (271 boys and 36 girls), 6-17 years of age, who had been treated with IR MPH for the past 6 months. The measures included the Chinese Health Questionnaire, Parental Bonding Instrument, Family APGAR, and Home Behaviors of the Social Adjustment Inventory for Children and Adolescents. RESULTS: Reasons for poor adherence (n = 79; 25.7%) included forgetting medication (72.7%), the medication having no effect (20.0%), and refusing medication (12.7%). Increased age and three-times-daily administration were the major predictors for poor adherence to IR MPH. Poor adherence was associated with increased degree of maternal psychological distress, indifferent parenting, maternal overprotection/control, poor family support, decreased interaction with parents, and increased problems at home. CONCLUSIONS: Findings indicate that multiple daily dosing of MPH increases the likelihood of poor adherence, particularly in adolescents, and that poor adherence is associated with impaired maternal/family process. Once-daily administration of MPH is necessary to improve adherence and to decrease the possible exacerbation of tense parent-child relationships caused by poor drug adherence.

Adolescent↗

Control of lymphocyte recirculation in man. I. Differential regulation of the peripheral lymph node homing receptor L-selectin on T cells during the virgin to memory cell transition.

Conventional virgin lymphocytes of a given class show relatively homogeneous recirculation through secondary lymphoid tissues, whereas memory/effector populations are composed of distinct subsets with differential, often tissue-selective migratory capability. In keeping with these observations, CD45RAhigh/ROlow "virgin" T cells in human peripheral blood uniformly express the peripheral lymph node homing receptor (HR) L-selectin, whereas among the CD45RAlow/ROhigh "memory/effector" subset, the expression of this HR is bimodal. To investigate the mechanisms responsible for the generation of memory/effector T cell subsets with differential homing potential, we developed a multiparameter flow cytometric technique that defines a common pathway of post-thymic T cell differentiation in secondary lymphoid tissues. Our analyses indicate that the virgin to memory T cell transition is characterized by a stepwise, unidirectional progression through distinct CD45RA+/RO+ intermediates that allow the in vivo discrimination of early, middle, and late transitional T cells. In normal peripheral blood, few T cells with a transitional phenotype are identified, but in secondary lymphoid tissues, 2 to 10% of T cells have this phenotype, including those CD45RA+ T cells that 1) are morphologically blasts, 2) are in S or G2/M phase of the cell cycle, or 3) express activation Ag. General adhesion molecules (LFA-1, LFA-3, ICAM-1) are uniformly up-regulated concordant with changes in T cell expression of CD45RA/RO in all tissues examined. Early in the transition, L-selectin is also uniformly up-regulated, but in subsequent stages, T cell expression of this HR is preferentially down-regulated in mucosal lymphoid tissues, and retained in peripheral lymph node. Differential regulation of L-selectin can also be demonstrated in vitro by the activation of virgin T cells in the presence of specific cytokines--IL-2 induces L-selectin down-regulation, whereas IL-6 and particularly TGF-beta 1 promote L-selectin up-regulation. Taken together, these findings support the hypothesis that local microenvironments within particular secondary lymphoid tissues influence HR expression at the time of CD45RA/RO conversion, and thereby contribute to the formation of CD45RAlow/ROhigh memory/effector T cell populations with tissue-selective homing behavior.

Adult↗

Ainsworth revisited: an empirical analysis of interactive behavior in the home.

Naturalistic assessment of maternal and infant interactive behavior using q-sorts has typically focused on rationally derived variables, such as maternal sensitivity and infant security. In the current study, behavior profiles characteristic of groups of young and adult mothers and their infants were derived empirically through q-factor analysis of the Maternal Behavior Q-sort (Version 3.0) and the Attachment Q-sort (Version 3.0). A three-factor solution best described the behavior profiles characteristic of young mothers. The identified factors were labeled: 'ignoring/neglecting versus interacting', 'accepting versus hostile/rejecting', and 'interfering'. The behavior of adult mothers was less variable and was described with only one factor, which corresponded to the 'accepting versus hostile/rejecting' factor. The factor solutions for infants of young and adult mothers were similar, with four identified factors, or behavioral profiles, discriminating between groups of infants with similar patterns of behavior: 'secure with mother', 'prefers visitor', 'socially withdrawn' and 'demanding with mother'. Infants of young and adult mothers differed with regard to their mean values on the first two identified factors. Results provide support for the relevance of rationally derived domains and criterion sorts in populations of both adult and young mothers, and suggest ways of progressing beyond the currently used, rationally derived variables in assessments of maternal and infant behavior in high- and low-risk populations.

Adolescent↗

[Adhesion molecules in dermato-oncology].

Adhesion molecules are cell surface proteins responsible for cell-cell and cell-matrix interactions. They represent a basis for physiologic and pathologic processes, especially for homing behavior, homeostasis of the immune response, inflammations and tumor metastasis. Recently, adhesions molecules such as CD44v6 have been shown to be expressed on tumor cells of cutaneous lymphomas with systemic tumor spread and thus play an important role in metastasis.

Cell Adhesion Molecules↗

Why do nursing home costs vary? The determinants of nursing home costs.

Since the costs of nursing home care are a major component of the rapidly rising costs of health care, it is appropriate to base public policy discussions about cost containment on the determinants of nursing home costs. This article investigates the determinants of nursing home operating costs and reviews the results of 11 related econometric cost analyses conducted by the authors. Single-equation cost analyses are developed for nursing homes in three states and in the nation. The cost results of a multi-equation model of nursing home behavior are also reviewed. The analyses indicate that facility size and occupancy rate are minimally important in determining cost variation. Facility characteristics, particularly type of facility and ownership, are important variables. Nonprofit facilities consistently had higher costs than for-profit facilities, after controlling for patient mix and service differences, and, in one analysis, for a measure of quality.

Costs and Cost Analysis↗

Once-daily atomoxetine treatment for children with attention-deficit/hyperactivity disorder, including an assessment of evening and morning behavior: a double-blind, placebo-controlled trial.

OBJECTIVES: Atomoxetine seems to be as effective for treating attention-deficit/hyperactivity disorder (ADHD) when the daily dose is administered once in the morning as when the dose is divided and administered in the morning and evening. In the present study, the efficacy of atomoxetine administered once daily among children with ADHD was assessed throughout the day, including the evening and early morning. Another goal was to determine how early in treatment it was possible to discern a specific effect of the drug on ADHD symptoms. METHODS: This study was a randomized, multicenter, double-blind, placebo-controlled trial conducted at 12 outpatient sites in the United States. A total of 197 children, 6 to 12 years of age, who had been diagnosed as having ADHD, on the basis of the Diagnostic and Statistical Manual of Mental Disorders (4th ed.) criteria, were randomized to receive 8 weeks of treatment with atomoxetine or placebo, dosed once daily in the mornings. ADHD symptoms were assessed with parent and investigator rating scales. The primary outcome measure was the Attention-Deficit/Hyperactivity Disorder Rating Scale-IV-Parent Version: Investigator-Administered and Scored total score. Daily parent assessments of children's home behaviors in the evening and early morning were recorded with an electronic data entry system. This instrument measures 11 specific morning or evening activities, including getting up and out of bed, doing or completing homework, and sitting through dinner. RESULTS: Seventy-one percent of the children enrolled were male, 69% met criteria for the combined subtype (both inattentive and hyperactive/impulsive symptoms), and the most common psychiatric comorbidity was oppositional defiant disorder (35%). Once-daily atomoxetine (final mean daily dose of 1.3 mg/kg) was significantly more effective than placebo in treating core symptoms of ADHD. Mean reductions in the Attention-Deficit/Hyperactivity Disorder Rating Scale-IV-Parent Version: Investigator-Administered and Scored total score were significantly greater for patients randomized to atomoxetine, beginning at the first visit after the initiation of treatment and continuing at all subsequent visits. Both inattentive and hyperactive/impulsive symptom clusters were significantly reduced with atomoxetine, compared with placebo. With continued treatment and dose titrations, core symptoms of ADHD continued to decrease throughout the 8-week study. Mean reductions in the daily parent assessment total scores for patients randomized to atomoxetine were superior during the first week, beginning with the first day of dosing, and were also superior at endpoint. Efficacy outcomes for the evening hours for atomoxetine-treated patients were superior to those for placebo-treated patients, as assessed with 2 different assessment scales. Decreases in the daily parent assessment morning subscores at endpoint showed a significant reduction in symptoms that lasted into the mornings. Rates of discontinuations attributable to adverse events were <5% for both groups. Adverse events reported significantly more frequently with atomoxetine were decreased appetite, somnolence, and fatigue. CONCLUSIONS: Among children 6 to 12 of age who had been diagnosed as having ADHD, once-daily administration of atomoxetine in the morning provided safe, rapid, continuous, symptom relief that lasted not only into the evening hours but also into the morning hours. Atomoxetine treatment was safe and well tolerated.

Atomoxetine Hydrochloride↗

HIV knowledge and sexual risk behaviors of street children in Takoradi, Ghana.

A pilot survey was conducted among 100 street children aged 11-19 years and data collected regarding HIV knowledge, risk behaviors, home and sexual experiences, and factors that contributed to their relocation to the street environment. Data indicated that 80% of the street children had at least minimal knowledge of HIV and 54% perceived themselves to be at risk for contracting HIV. More than three-fourths of the females, and over half of the boys reported ever having sex. There were significant differences between males and females for sexual activity, physical and sexual abuse, and prostitution, as girls were more likely to be sexually active, physically abused, and involved in prostitution.

Attitude to Health↗