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PubMed1984

Meeting the needs of the teen-age pregnant student: an in-school program that works.

The drop-out rate for pregnant students in the York (Pennsylvania) City School District is dramatically lower than the national average because the district recognized the need for meeting the unique problems of the pregnant student. In York, as in the rest of the nation, teen-age pregnancy was on the increase. Administrators of the district realized that a separately housed alternative education program would be too costly. In January 1979, the authors designed and implemented an in-school program called "Changing Roles." Five years later, that program has become an important factor in keeping the majority of pregnant students in school, at the same time, providing the girls the special information they need. In the 1982-83 school year, only 9.5% of the pregnant students dropped out of York City schools. This rate is far below the national drop-out rate of 80% to 90%.

Adolescent↗
PubMed1996

Drug use among adolescent mothers: prepregnancy to 18 months postpartum.

PURPOSE: Little is known about the substance use patterns of adolescent mothers, particularly in the postpartum period. This study provides descriptive, longitudinal data on the substance use behavior of a cohort of adolescent mothers. METHODS: A total of 241 pregnant adolescents, under 18 years old and planning to carry the pregnancy to term, completed the initial interview. Respondents were interviewed again at 1, 6, 12, and 18 months postpartum. The data reported here are based on the 229 respondents who completed all five interviews. RESULTS: Use of all substances decreased substantially during pregnancy, but increased steadily in the first 6 months postpartum. A similar pattern was observed for regular use of multiple substances. Regular use before and after the pregnancy, but not during it, was the most common pattern of substance use. CONCLUSIONS: The prevalence of substance use among adolescent mothers is significant. To capitalize on the large decreases in use during pregnancy, drug prevention programs for adolescent mothers should target the first 6 months postpartum.

Adolescent↗
PubMed2000

A kinetic chain approach for shoulder rehabilitation.

OBJECTIVE: To introduce an approach to shoulder rehabilitation that integrates the kinetic chain throughout the rehabilitation program while providing the theoretical rationale for this program. BACKGROUND: The focus of a typical rehabilitation program is to identify and treat the involved structures. However, in activities of sport and daily life, the body does not operate in isolated segments but rather works as a dynamic unit. Recently, rehabilitation programs have emphasized closed kinetic chain exercises, core-stabilization exercises, and functional programs. These components are implemented as distinct entities and are used toward the end of the rehabilitation program. DESCRIPTION: Kinetic chain shoulder rehabilitation incorporates the kinetic link biomechanical model and proximal-to-distal motor-activation patterns with proprioceptive neuromuscular facilitation and closed kinetic chain exercise techniques. This approach focuses on movement patterns rather than isolated muscle exercises. Patterns sequentially use the leg, trunk, and scapular musculature to activate weakened shoulder musculature, gain active range of motion, and increase strength. The paradigm of kinetic chain shoulder rehabilitation suggests that functional movement patterns and closed kinetic chain exercises should be incorporated throughout the rehabilitation process. CLINICAL ADVANTAGES: The exercises in this approach are consistent with biomechanical models, apply biomechanical and motor control theory, and work toward sport specificity. The exercises are designed to stimulate weakened tissue by motion and force production in the adjacent kinetic link segments.

Journal Article↗
PubMedDate not supplied

Principles of disaster management. Lesson 2: Program planning.

Many of the problems that develop in disaster management can be avoided with good program planning. Assessment following a disaster is essential. Needs assessment is essential in the early phases of a disaster and situation assessments become more important as the disaster process continues. Both are dynamic and continuous processes. Program planning requires setting policies, goals, and objectives with the end result of selection of strategies to accomplish the mission. Implementation of the strategies requires identification of funding sources, allocation of the resources, development management, and monitoring of the progress. Together, these elements should result in a balanced and successful program.

Budgets↗
PubMed1989

Fertility, menstrual characteristics, and contraceptive practices among white, black, and Southeast Asian refugee adolescents.

This study compares fertility and menstrual characteristics and contraceptive practices of white, black, and Southeast Asian refugee adolescents participating in the Minneapolis Health Department's Maternal and Infant Care Program between 1980 and 1982. Mean ages were similar among all racial groups; however, half the Hmong adolescents had a live birth as compared to less than 25% of the other racial groups. More than 75% of the Hmong and other Southeast Asian adolescents were married as compared to 11% of the whites and 8% of the blacks. Menarche was significantly later (2 years) for Hmong and other Southeast Asians, and the interval between menarche and first pregnancy was significantly shorter for the Hmong. While more than half of the whites and blacks previously used contraception, 14% of the Hmong and 29% of the other Southeast Asians had used contraception. Oral contraceptives were the most frequently used method for whites, blacks, and Southeast Asians; the Hmong were equally likely to choose oral contraceptives or barrier methods. The Hmong were less likely to choose contraception postpartum than were the other groups.

Adolescent↗
PubMed2003

3D-QSAR and docking studies on 4-anilinoquinazoline and 4-anilinoquinoline epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors.

The overexpression and/or mutation of the epidermal growth factor receptor (EGFR) tyrosine kinase has been observed in many human solid tumors, and is under intense investigation as a novel anticancer molecular target. Comparative 3D-QSAR analyses using different alignments were undertaken employing comparative molecular field analysis (CoMFA) and comparative molecular similarity analysis (CoMSIA) for 122 anilinoquinazoline and 50 anilinoquinoline inhibitors of EGFR kinase. The SYBYL multifit alignment rule was applied to three different conformational templates, two obtained from a MacroModel Monte Carlo conformational search, and one from the bound conformation of erlotinib in complex with EGFR in the X-ray crystal structure. In addition, a flexible ligand docking alignment obtained with the GOLD docking program, and a novel flexible receptor-guided consensus dynamics alignment obtained with the DISCOVER program in the INSIGHTII modeling package were also investigated. 3D-QSAR models with q2 values up to 0.70 and r2 values up to 0.97 were obtained. Among the 4-anilinoquinazoline set, the q2 values were similar, but the ability of the different conformational models to predict the activities of an external test set varied considerably. In this regard, the model derived using the X-ray crystallographically determined bioactive conformation of erlotinib afforded the best predictive model. Electrostatic, hydrophobic and H-bond donor descriptors contributed the most to the QSAR models of the 4-anilinoquinazolines, whereas electrostatic, hydrophobic and H-bond acceptor descriptors contributed the most to the 4-anilinoquinoline QSAR, particularly the H-bond acceptor descriptor. A novel receptor-guided consensus dynamics alignment has also been introduced for 3D-QSAR studies. This new alignment method may incorporate to some extent ligand-receptor induced fit effects into 3D-QSAR models.

Aniline Compounds↗
PubMed1984

Sexual function during the puerperium.

Of 328 women interviewed at a postnatal clinic, 166 (50.6%) had resumed sexual intercourse, the average interval after delivery being 5 weeks postpartum. Of the various social and clinical factors examined, resumption of coitus was related only to marital status, vaginal laceration, and continuing vaginal bleeding. Of the sexually active group, 89% were practicing effective contraception.

Adult↗
PubMed1996

Dynamical complexity in age-structured models of the transmission of the measles virus: epidemiological implications at high levels of vaccine uptake.

This article explores the effect of increasingly finely stratified age structure on the dynamical properties of deterministic metapopulation models of the transmission of the measles virus. The dynamical simplicity of earlier age-structured models is shown to break down once the age-specific force of infection is no longer assumed to be constant across all child age classes below 5 years of age. While the biennial epidemics characteristic of earlier models are still observed, additional higher period stable cycles arise and coexist with the biennial cycle. The existence of multiple stable limit cycles necessarily implies model sensitivity on initial conditions, and for certain parameter values, chaotic dynamics are observed. Using a novel parameterization of the magnitude of seasonal forcing we are also able to make more biologically relevant comparisons between the dynamics of age- and non-age-structured models than have hitherto been possible. The epidemiological significance of these results is discussed, and we demonstrate that perturbations of the kind produced by intensive vaccination programs can shift transmission dynamics between biennial and triennial cycles. The possible implications of this work for studies of intermittency and infection persistence are also considered.

Adolescent↗
PubMed1998

Solution structure of an artificial Fe8S8 ferredoxin: the D13C variant of Bacillus schlegelii Fe7S8 ferredoxin.

The solution structure of the D13C variant of the thermostable Fe7S8 ferredoxin from Bacillus schlegelii has been determined by 1H-NMR spectroscopy in its oxidized form. In a variable-temperature NMR study the D13C variant was as thermostable (up to 90 degrees C) as the wild-type protein (WT). Seventy-five out of 77 amino acid residues and 81% of all theoretically expected proton resonances in the D13C Fe8S8 protein have been assigned. Its structure was determined through torsion angle dynamics calculations with the program DYANA, using 935 meaningful NOEs (from a total of 1251), hydrogen bond constraints, and NMR-derived dihedral angle constraints for the cluster-ligating cysteines. Afterwards, restrained energy minimization and restrained molecular dynamics were applied to each conformer of the family. The final family of 20 structures has RMSD values from the mean structure of 0.055 nm for the backbone atoms and of 0.099 nm for all heavy atoms. The overall folding of the WT is maintained in the mutant, except for the immediate vicinity of the new cysteine, which becomes much more similar to native Fe8S8 proteins. The two residues at positions 11 and 12, which constitute an insertion with respect to all known Fe8S8 proteins, assume a conformation that does not prevent the preceding and following residues from folding like in native Fe8S8 proteins. Clear evidence for the existence of two conformations involving almost half of the amino acid residues was found. The two conformations are structurally indistinguishable. Temperature-dependent NMR experiments show that one of them is thermodynamically more stable than the other.

Amino Acid Sequence↗
PubMedDate not supplied

Measuring accessibility to family planning services in rural Thailand.

There are a variety of ways to conceptualize and measure accessibility to contraceptive services and supplies. Using detailed data for rural Thailand, a multiplicity of reasonable measures are developed that reflect time and/or distance to various government program outlets. Many of these are only moderately correlated with one another, and to an important extent, different measures show different associations with levels of contraceptive prevalence. Clearly there is a general need in this area of investigation to pay more attention to the measurement of accessibility as a community characteristic and to consider the sensitivity of results to alternate measures.

Adolescent↗
PubMed1978

Management of teenage pregnancies in three different health care settings.

A retrospective study was undertaken to determine if differences existed in obstetric outcome, contraceptive usage, and repeat pregnancy rates of teenage patients cared for in three different health care settings. The sites included the Rochester Adolescent Maternity Project (RAMP), a traditional obstetric clinic, and a neighborhood health center. Comparison of the three groups revealed that RAMP patients experienced a lower incidence of anemia and preeclampsia than patients in the other programs. At one year postpartum, 25% of the hospital clinic patients were using contraception compared to 45% for the health center and 49% for RAMP patients, compared to 15.8% for the health center and 6.5% for the RAMP group.

Adolescent↗
PubMed1980

Computer measurement of dynamic compliance: technique and reproducibility in man.

A computer program was developed to calculate the frequency dependence of dynamic compliance (Cdyn) using continuous data analysis. Cdyn was measured repeatedly in eight normal human subjects over a 2-yr period. Comparison with Cdyn results measured manually showed that the computer program improved 10-fold the ratio of variance within subjects to between subjects of the compliance at specific frequencies, but there was only slight improvement in indices of the slope of the frequency dependence of compliance. We suggest that the absolute compliance at specific frequencies merits further consideration as a pathophysiological measurement and that, if the frequency dependence of compliance continues to be used, standardization of its calculation should be applied and the wide normal range should be more widely appreciated. Measurements of Cdyn in subjects breathing 80% helium-20% oxygen confirm that inertia is insignificant when breathing with tidal volumes of less than 500 ml and frequency of less than 1.5 Hz.

Diagnosis, Computer-Assisted↗
PubMed2002

Clinical implementation of intensity-modulated arc therapy.

PURPOSE: Intensity-modulated arc therapy (IMAT) is a method for delivering intensity-modulated radiation therapy (IMRT) using rotational beams. During delivery, the field shape, formed by a multileaf collimator (MLC), changes constantly. The objectives of this study were to (1) clinically implement the IMAT technique, and (2) evaluate the dosimetry in comparison with conventional three-dimensional (3D) conformal techniques. METHODS AND MATERIALS: Forward planning with a commercial system (RenderPlan 3D, Precision Therapy International, Inc., Norcross, GA) was used for IMAT planning. Arcs were approximated as multiple shaped fields spaced every 5-10 degrees around the patient. The number and ranges of the arcs were chosen manually. Multiple coplanar, superimposing arcs or noncoplanar arcs with or without a wedge were allowed. For comparison, conventional 3D conformal treatment plans were generated with the same commercial forward planning system as for IMAT. Intensity-modulated treatment plans were also created with a commercial inverse planning system (CORVUS, Nomos Corporation). A leaf-sequencing program was developed to generate the dynamic MLC prescriptions. IMAT treatment delivery was accomplished by programming the linear accelerator (linac) to deliver an arc and the MLC to step through a sequence of fields. Both gantry rotation and leaf motion were enslaved to the delivered MUs. Dosimetric accuracy of the entire process was verified with phantoms before IMAT was used clinically. For each IMAT treatment, a dry run was performed to assess the geometric and dosimetric accuracy. Both the central axis dose and dose distributions were measured and compared with predictions by the planning system. RESULTS: By the end of May 2001, 50 patients had completed their treatments with the IMAT technique. Two to five arcs were needed to achieve highly conformal dose distributions. The IMAT plans provided better dose uniformity in the target and lower doses to normal structures than 3D conformal plans. The results varied when the comparison was made with fixed gantry IMRT. In general, IMAT plans provided more uniform dose distributions in the target, whereas the inverse-planned fixed gantry treatments had greater flexibility in controlling dose to the critical structures. Because the field sizes and shapes used in the IMAT were similar to those used in conventional treatments, the dosimetric uncertainty was very small. Of the first 32 patients treated, the average difference between the measured and predicted doses was -0.54 +/- 1.72% at isocenter. The 80%-95% isodose contours measured with film dosimetry matched those predicted by the planning system to within 2 mm. The planning time for IMAT was slightly longer than for generating conventional 3D conformal plans. However, because of the need to create phantom plans for the dry run, the overall planning time was doubled. The average time a patient spent on the table for IMAT treatment was similar to conventional treatments. CONCLUSION: Initial results demonstrated the feasibility and accuracy of IMAT for achieving highly conformal dose distributions for different sites. If treatment plans can be optimized for IMAT cone beam delivery, we expect IMAT to achieve dose distributions that rival both slice-based and fixed-field IMRT techniques. The efficient delivery with existing linac and MLC makes IMAT a practical choice.

Brain Neoplasms↗
PubMed1998

Adolescent satisfaction with postpartum contraception and body weight concerns.

PURPOSE: To explore factors that could be related to adolescents' satisfaction with postpartum contraceptives. METHODS: Three focus groups were conducted with a total of 22 adolescent mothers. The groups covered four content areas: feelings about birth control since becoming a mother, decision making about contraceptive use, factors that would influence contraceptive discontinuation, and the perceived side effects of the current contraceptive. Audiotapes from the groups were analyzed to identify major themes. RESULTS: Nineteen subjects received Depo-Provera when they were discharged after delivery and the majority reported that menstrual irregularities and weight gain were side effects. Two body weight-related themes were dominant: dissatisfaction with heavier than desired body weights and resignation about not returning to prepregnancy weights. CONCLUSIONS: Depo-Provera may be an effective contraceptive for adolescent mothers who are generally at high risk for rapid repeat pregnancy. This qualitative study suggests that contraceptive continuation may be enhanced with specific counselling to manage body weight concerns.

Adolescent↗
PubMed2004

Cooperative effects on the formation of intercalation sites.

Daunomycin is one of the most important agents used in anticancer chemotherapy. It interacts with DNA through intercalation of its planar chromophore between successive base pairs. The effect of intercalation on structure, dynamics and energetics is the topic of a wealth of scientific studies. In the present study, we report a computational examination of the energetics of the intercalation process. In detail, we concentrate on the energetic penalty that intercalation of daunomycin introduces into DNA by disturbing it from its unbound conformation. For these means, we are analyzing already published molecular dynamics simulations of daunomycin-DNA complexes and present novel simulations of a bisdaunomycin-DNA and a 9-dehydroxydaunomycin-DNA intercalated complex using the MM-GBSA module implemented in the AMBER suite of programs. Using this molecular dynamics based, continuum solvent method we were able to calculate the energy required to form an intercalation site. Consequently, we compare the free energy of the duplex d(CGCGCGATCGCGCG)(2) in the B-form conformation with the respective conformations when intercalated with daunomycin and a bisintercalating analog. Our results show that the introduction of one single intercalation site costs approximately 32 kcal/mol. For double intercalation, or intercalation of the bisintercalator, the respective value for one intercalation site decreases to 27 and 24 kcal/mol, respectively, at a theoretical salt concentration of 0.15 M. This proposes that at least in these cases, a synergistic effect takes place. Although it is well known that intercalation leads to substantial disturbance of the DNA conformation, already performed investigations suggest a lower energetic penalty. Nevertheless to the best of our knowledge the calculations presented here are the most complete ones and consider hydration effects for the first time. The interaction energy between the ligand and the DNA certainly over-compensates this penalty for introducing the intercalation site and thus favors complexation. Such analyses are helpful for the description of allosteric effects in protein ligand binding.

Antibiotics, Antineoplastic↗