Allogeneic bone grafting of calvarial defects: an experimental study in the rabbit

The purpose of this study was to investigate the incorporation of fresh frozen irradiated membranous allogeneic bone grafts into critical size calvarial defects in the rabbit. Fifteen rabbits had calvarial defects prepared. Twelve rabbits received allogeneic grafts and three received autogenous bone grafts. The rabbits were sacrificed at 9 and 12 months postoperatively, and the specimens were examined radiologically, histopathologically and with fluorescence microscopy. Neovascularization, bone marrow regeneration and new bone formation was evident throughout the grafts however revitalization of the entire graft was incomplete at 12 months. This study revealed that the FFI membranous grafts were well incorporated into rabbit calvarial defects.

Development and validation of a self-completed HIV symptom index

Traditional, open-ended provider questions regarding patient symptoms are insensitive. Better methods are needed to measure symptoms for clinical management, patient-oriented research, and adverse drug-event reporting. Our objective was to develop and initially validate a brief, self-reported HIV symptom index tailored to patients exposed to multidrug antiretroviral therapies and protease inhibitors, and to compare the new index to existing symptom measures. The research design was a multistage design including quantitative review of existing literature, qualitative and quantitative analyses of pilot data, and quantitative analyses of a prospective sample. Statistical analyses include frequencies, chi-square tests for significance, linear and logistic regression. The subjects were from a multisite convenience sample (n = 73) within the AIDS Clinical Trials Group and a prospective sample from the Cleveland Veterans Affairs Medical Center (n = 115). Measures were patient-reported symptoms and health-related quality of life, physician-assessed disease severity, CD4 cell count, and HIV-1 RNA viral quantification. A 20-item, self-completed HIV symptom index was developed based upon prior reports of symptom frequency and bother and expert opinion. When compared with prior measures the index included more frequent and bothersome symptoms, yet was easier to use (self-report rather than provider interview). The index required less than 5 minutes to complete, achieved excellent completion rates, and was thought comprehensive and comprehensible in a convenience sample. It was further tested in a prospective sample of patients and demonstrated strong associations with physical and mental health summary scores and with disease severity. These associations were independent of CD4 cell count and HIV-1 RNA viral quantification. This 20-item HIV symptom index has demonstrated construct validity, and offers a simple and rational approach to measuring HIV symptoms for clinical management, patient-oriented research, and adverse drug reporting.

The use of a pressure manometer enhances student physiotherapists' performance during manual hyperinflation

The purpose of this study was to determine the effect of using a pressure manometer on the delivery of target airway pressures during manual hyperinflation by student physiotherapists in the laboratory and clinical environments. Manual hyperinflations were delivered under control and feedback conditions where the feedback condition involved manual hyperinflation with a pressure manometer. Compared with control conditions, the availability of a manometer significantly decreased the mean absolute error (9.5 +/- 0.9 cm H2O to 1.4 +/- 0.2 cm H2O) and mean variable error (2.2 +/- 0.3 cm H2O to 1.3 +/- 0.1cm H2O) of peak airway pressures during manual hyperinflation. In addition, the availability of a manometer negated the influence of environment on accuracy. Therefore, the availability of a pressure manometer provided an effective clinical tool that was easily used to provide feedback regarding the peak airway pressures delivered during manual hyperinflation.

Parent to child transmission of HIV: policy considerations in the Asia-Pacific region

BACKGROUND

As HIV spreads through many countries in Asia and the Pacific, women of reproductive age are becoming infected and we can expect increasing numbers of infants to be infected. Rapid advances in knowledge about mother to child transmission (MTCT), new findings from intervention studies, recognition of complex ethical implications, and changing attitudes and behaviours combine to create uncertainty for policy makers.

OBJECTIVE

Policy makers need sound advice but MTCT and its prevention are complicated topics. We aim to provide an overview of MTCT of HIV and suggest some key points to consider in the allocation of resources.

STUDY DESIGN

This is a policy analysis based on review of the literature, consultation with policy makers and researchers, and observations in the context of projects in developing countries.

RESULTS

The risk of MTCT is between 15 and 40%, but the use of antiretroviral prophylaxis, elective caesarean section, and replacement of breastfeeding can reduce this to less than 4%. But most infected women in developing countries are unaware that they are HIV-infected and do not yet have access to these 'test-dependent' interventions (interventions based on testing for HIV infection). Population-based strategies that address known influences on the risk of MTCT can be implemented with benefits for the health of both men and women. The test-dependent interventions can have adverse effects as well as benefits, careful preparation is necessary before they are introduced in resource poor settings. The public health impact of test-dependent interventions is limited by difficulties in achieving wide coverage and because they miss women who become infected late in pregnancy or during lactation who have the highest risk of MTCT.

CONCLUSIONS

We argue for a broad response to the problems raised by MTCT of HIV that includes gathering information to inform the introduction of strategies that do not depend on testing for HIV infection as well as the test-dependent interventions, community education that reaches men as well as women; strengthening of reproductive health services; and mobilising communities to care for infected women, their families, and orphans.

Follistatin-related protein (FSRP): a new member of the follistatin gene family

The identification and characterization of follistatin related protein (FSRP) suggests that the follistatin (FS) gene family may actually contain two sub-families. The first includes FS and FSRP by virtue of their high degree of structural homology and comparable activin-binding activity, while the second sub-family contains extracellular matrix proteins that possess one or more 10-cysteine FS domains, but do not bind activin or related TGF-beta family members. Characterization of FSRP indicates that it binds activin with similar affinity and selectivity as FS, but does not bind heparin. Furthermore, although FSRP inhibits activin-mediated gene transcription in heterologous assays, FSRP is much less active than FS in the rat pituitary bioassay. When overexpressed in transgenic mice, FSRP may lead to interruption of follicular development and fertility in females but appears to have only a modest effect on males. These results suggest that FSRP is a structural, but not necessarily a functional homologue of FS.

The Female Sexuality Questionnaire: instrument development

The purpose of this study was to develop and validate a measure of female sexuality, the Female Sexuality Questionnaire (FSQ). A survey design was employed for the study. The sample included 262 adult women ages 18 to 81 (M = 32). Five hundred questionnaires were distributed to a diverse female population representing multiple geographic areas in the U.S. and Canada. Participants were healthy (as per self-report), sexually active and engaged in an intimate relationship. The majority of the sample was premenopausal. Item stems for the FSQ were developed based on the literature and the domain-referenced approach for item generation. A pool of 70 items generated to represent 6 theoretical domains of female sexuality: Reproduction, Beliefs, Intimacy, Body Image, Physical Responsiveness, and Satisfaction were subjected to systematic review by a panel of experts. A 5-point self-report response scale was appended to the 54 items surviving judges' reviews (criterion validity index of 91.3 for the pool of retained items). Data screening and item analysis was performed and yielded 13 items which were removed prior to principal factor analysis (PFA) resulting in a sample of 218 subjects and 41 items. The PFA with quartrimax rotation resulted in a 5-factor solution. Four of the five were consistent with the hypothesized domains of Satisfaction, Physical Responsiveness, Beliefs, and Body Image. The fifth factor suggested an association with Intimacy, and was renamed Relationships. The hypothesized domain of Reproduction was not supported. Twelve items failed to load on any of the factors. Recommendations for alternations of the final version of the FSQ are based upon the empirical results of the item analysis and PFA.

Prospective study of the incidence, aetiology and outcome of adult lower respiratory tract illness in the community

BACKGROUND

Acute lower respiratory tract illness in previously well adults is usually labelled as acute bronchitis and treated with antibiotics without establishing the aetiology. Viral infection is thought to be the cause in most cases. We have investigated the incidence, aetiology, and outcome of this condition.

METHODS

Previously well adults from a stable suburban population consulting over one year with a lower respiratory tract illness were studied. For the first six months detailed investigations identified predetermined direct and indirect markers of infection. Evidence of infection was assessed in relation to presenting clinical features, indirect markers of infection, antibiotic use, and outcome.

RESULTS

Consultations were very common, particularly in younger women (70/1000 per year in previously well women aged 16-39 years), mainly in the winter months; 638 patients consulted, of whom 316 were investigated. Pathogens were identified in 173 (55%) cases: bacteria in 82 (Streptococcus pneumoniae 54, Haemophilus influenzae 31, Moraxella catarrhalis 7), atypical organisms in 75 (Chlamydia pneumoniae 55, Mycoplasma pneumoniae 23), and viruses in 61 (influenza 23). Seventy nine (24%) had indirect evidence of infection. Bacterial and atypical infection correlated with changes in the chest radiograph and high levels of C reactive protein but not with (a) the GP's clinical assessment of whether infection was present, (b) clinical features other than focal chest signs, and (c) outcome, whether or not appropriate antibiotics were prescribed.

CONCLUSIONS

Over 50% of patients have direct and/or indirect evidence of infection, most commonly bacterial and atypical pathogens, but the outcome is unrelated to the identified pathogens. Many patients improve without antibiotics and investigations do not help in the management of these patients. GPs can reassure patients of the causes and usual outcome of this self-limiting condition.

A study of the cycle of abuse among child molesters

The current study was designed to determine whether there is support for the cycle of abuse theory among child molesters. A group of 147 sex offenders on probation were used in this study. The victims of 32 of these offenders were under the age of 10, and 19 of these offenders reported a history of childhood sexual abuse. Results indicate that being abused as a child is related to being a child molester. It was also found that the MMPI-2 did not predict the status of the subjects in regard to being abused as a child and having a victim under 10-years-old.

Transarticular joint reconstruction and indirect plate osteosynthesis for complex distal supracondylar femoral fractures

In a prospective study conducted between 1992 and 1995, displaced Müller type C2-C3 intraarticular fractures of the distal femur were treated using an indirect plate fixation technique and a lateral parapatellar arthrotomy for the direct reduction of the condylar block. There were 6 closed, and 2 open fractures (1 grade II and 1 grade IIIB). Following reconstruction of the articular block, the block was indirectly reduced and fixed to the shaft by a plate inserted by the retrograde method beneath the vastus lateralis. Transcutaneous/transmuscular screws were used to fix the plate to the shaft. Time to bone healing was 12 weeks (median range 8-17 weeks) after surgery without needing primary or secondary bone grafts. There were no infections or refractures. Except for one case which required a corrective osteotomy for 10 degrees of varus malalignment, there were no revisions. According to the Neer score, there were 6 excellent or satisfactory results, 2 unsatisfactory results, and no failures. At follow-up, there were 2 varus-valgus deformities greater than 5 degrees, 2 leg length discrepancies greater than 10 mm, and 2 rotational deformities of 15 degrees. The treatment results for complex supracondylar/intracondylar fractures of the distal femur obtained with this technique compare favourably with other reported series using different techniques without the added morbidity associated with autogenous bone grafting. However, the surgical technique is demanding and special care must be taken to ensure correct axial alignment.

Binding mode of the 4-anilinoquinazoline class of protein kinase inhibitor: X-ray crystallographic studies of 4-anilinoquinazolines bound to cyclin-dependent kinase 2 and p38 kinase

4-Anilinoquinazolines represent an important class of protein kinase inhibitor. Modes of binding for two members of this inhibitor class were determined by X-ray crystallographic analysis of one inhibitor (4-[3-hydroxyanilino]-6,7-dimethoxyquinazoline) in complex with cyclin-dependent kinase 2 (CDK2) and the other (4-[3-methylsulfanylanilino]-6,7-dimethoxyquinazoline) in complex with p38 kinase. In both inhibitor/kinase structures, the 4-anilinoquinazoline was bound in the ATP site with the quinazoline ring system oriented along the peptide strand that links the two domains of the protein and with the anilino substituent projecting into a hydrophobic pocket within the protein interior. In each case, the nitrogen at position-1 of the quinazoline accepted a hydrogen bond from a backbone NH (CDK2, Leu-83; p38, Met-109) of the domain connector strand, and aromatic hydrogen atoms at C2 and C8 interacted with backbone carbonyl oxygen atoms of the peptide strand. The anilino group of the CDK2-bound compound was essentially coplanar with the quinazoline ring system and occupied a pocket between Lys-33 and Phe-80. For the p38-bound inhibitor, the anilino group was angled out of plane and was positioned between Lys-53 and Thr-106 in a manner similar to that observed for the aryl substituent of the pyridinylimidazole class of inhibitor.

Cyclophosphamide, cytosine arabinoside and TBI as a conditioning regimen for allogeneic bone marrow transplantation in patients with leukemia

This is a prospective study designed to determine the toxicity, efficacy and antileukemic effect of high-dose cytosine arabinoside (ara-C), cyclophosphamide and total body irradiation (TBI) as a myeloablative regimen prior to allogeneic bone marrow transplantation for patients with hematologic malignancies. Fifty-eight patients with hematologic malignancies were treated with cyclophosphamide, high-dose ara-C and total body irradiation (TBI) followed by allogeneic bone marrow transplantation. Fifty patients had good prognosis disease and eight had poor prognosis disease. Cyclosporine and short-course methotrexate were used for graft-versus-host disease (GVHD) prophylaxis. The conditioning regimen consisted of ara-C 3000 mg/m2 twice a day x six doses on days -7, -6, and -5; cyclophosphamide 1800 mg/m2 on days -4 and -3; and TBI 1400 cGy midline dose at 5 cGy/min in eight total fractions administered twice a day on days -4, -3, -2, and -1. The bone marrow was infused on day 0 (zero). Toxicity related to the conditioning regimen was comparable to that reported with other conditioning regimens, except for diarrhea which appears to be more frequent. The actuarial survival at 1 year was 69% (58-82) and at 5 years was 54% (42-69) with the numbers in parentheses representing the 95% confidence interval of the Kaplan-Meier estimate. After a median follow-up of 28 months, 31 of 58 (53%) patients are alive without evidence of disease. Only four of the 58 patients (7%) have relapsed. Cyclophosphamide, ara-C and TBI is a safe and effective myeloablative regimen for patients with leukemia. The overall relapse rate in our study was 7% with a median follow-up of 28 months and appears to be lower than relapse rates reported in other series. This is probably due to the added antileukemic effect of ara-C. This regimen should be compared with other myeloablative regimens in a controlled study.

Standardized screening of elderly patients' needs for social work assessment in primary care: use of the SF-36

Fewer hospitalizations and decreased lengths of stay in the hospital have resulted in an increased need for extensive support services and continuing care planning for elderly people in primary care. Early identification of elderly patients needing community and hospital nonmedical services is necessary so that timely appropriate services can be delivered. This study addresses the issue of whether a standardized health-related quality of life questionnaire, the SF-36, can be used independently as a screen predicting primary care elderly patients' needs for social work assessment. In addition, the question of what scales on the SF-36 a social worker would use to screen patients in need of assessment is explored.

Plate osteosynthesis of the distal femur: surgical techniques and results

Over the past three decades, the techniques for internal fixation of the distal femur have evolved to provide reliably successful results. The improved outcomes of plate osteosynthesis of distal femur fractures are because of better implants, techniques of anatomic reduction and soft tissue handling, and post-fixation stability with early motion. We review the traditional Arbeitsgemeinschaft für Osteosynthesefragen (AO) surgical techniques for plate osteosynthesis of the distal femur and the results reported using these methods.

Voltage-Biased Superconducting Transition-Edge Bolometer with Strong Electrothermal Feedback Operated at 370 mK

We present an experimental study of a composite voltage-biased superconducting bolometer (VSB). The tested VSB consists of a Ti-film superconducting thermometer (T(c) ~375 mK) on a Si substrate suspended by NbTi superconducting leads. A resistor attached to the substrate provides calibrated heat input into the bolometer. The current through the bolometer is measured with a superconducting quantum interference device ammeter. Strong negative electrothermal feedback fixes the bolometer temperature at T(c) and reduces the measured response time from 2.6 s to 13 ms. As predicted, the measured current responsivity of the bolometer is equal to the inverse of the bias voltage. A noise equivalent power of 5 x 10(-17) W/ radicalHz was measured for a thermal conductance G ~ 4.7 x 10(-10) W/K, which is consistent with the expected thermal noise. Excess noise was observed for bias conditions for which the electrothermal feedback strength was close to maximum.

Crystal structure of the catalytic domain of the human cell cycle control phosphatase, Cdc25A

Cdc25 phosphatases activate the cell division kinases throughout the cell cycle. The 2.3 A structure of the human Cdc25A catalytic domain reveals a small alpha/beta domain with a fold unlike previously described phosphatase structures but identical to rhodanese, a sulfur-transfer protein. Only the active-site loop, containing the Cys-(X)5-Arg motif, shows similarity to the tyrosine phosphatases. In some crystals, the catalytic Cys-430 forms a disulfide bond with the invariant Cys-384, suggesting that Cdc25 may be self-inhibited during oxidative stress. Asp-383, previously proposed to be the general acid, instead serves a structural role, forming a conserved buried salt-bridge. We propose that Glu-431 may act as a general acid. Structure-based alignments suggest that the noncatalytic domain of the MAP kinase phosphatases will share this topology, as will ACR2, a eukaryotic arsenical resistance protein.

Recombinant human CXC-chemokine receptor-4 in melanophores are linked to Gi protein: seven transmembrane coreceptors for human immunodeficiency virus entry into cells

This article describes the transient expression of the CXC chemokine receptor-4 in Xenopus laevis melanophores and the resulting functional assay for the endogenous ligand for this receptor stromal cell-derived factor (SDF)-1alpha. Specifically, it will be shown that SDF-1alpha produces increased light transmittance in transfected cells that is consistent with the activation of Gi protein. This stimulus pathway is further implicated by the abolition of this response after pretreatment of the cells with pertussis toxin, a known method for the inactivation of Gi protein. The fact that SDF-1alpha does not produce responses in nontransfected cells and that treatment of the cells with 12G5, an antibody specific for the CXC chemokine receptor-4, eliminates this response indicates that this ligand produces responses by activation of this receptor in these cells. The possible relevance to human immunodeficiency virus (HIV) entry into cells was explored by observing the effects of SDF-1alpha on HIV-mediated cell fusion. It was found that SDF-1alpha blocked cell-to-cell fusion (as has been previously reported) at concentrations 1200-fold greater than those required to produce Gi protein mediated responses. The implications of the functional assay to screening for new drugs to block HIV-mediated fusion is discussed.

Influence of patients' expectations on antibiotic management of acute lower respiratory tract illness in general practice: questionnaire study

OBJECTIVE

To assess patients' views and expectations when they consult their general practitioner with acute lower respiratory symptoms and the influence these have on management.

DESIGN

General practitioners studied consecutive, previously well adults and recorded clinical data, the certainty regarding their prescribing decision, and the influence of non-clinical factors on that decision. Patients completed a questionnaire at home after the consultation.

SETTING

76 doctors from suburban, inner city, and rural practices.

SUBJECTS

1014 eligible patients entered; 787 (78%) returned the questionnaire.

MAIN OUTCOME MEASURES

The views of the patient, the views of and antibiotic prescription by the doctor.

RESULTS

Most patients thought that their symptoms were caused by an infection (662) and that antibiotics would help (656) and had both wanted (564) and expected (561) such a prescription. 146 requested an antibiotic, 587 received one. Of the 643 patients who thought they had an infection, 582 wanted an antibiotic and thought it would help. Severity of symptoms did not relate to wanting antibiotics. For those prescribed antibiotics, their doctor thought they were definitely indicated in only 116 cases and not indicated in 126. Patient pressure most commonly influenced the decision to prescribe even when the doctor thought antibiotics were not indicated. Doctors considered antibiotics definitely indicated in only 1% of the group in whom patient pressure influenced the prescribing decision. Patients who did not receive an antibiotic that they wanted were much more likely to express dissatisfaction. Dissatisfied patients reconsulted for the same symptoms twice as often as satisfied patients.

CONCLUSION

Patients presenting with acute lower respiratory symptoms often believe that infection is the problem and antibiotics the answer. Patients' expectations have a significant influence on prescribing, even when their doctor judges that antibiotics are not indicated.

Phorbol esters and SDF-1 induce rapid endocytosis and down modulation of the chemokine receptor CXCR4

The chemokine receptor CXCR4 is required, together with CD4, for entry by some isolates of HIV-1, particularly those that emerge late in infection. The use of CXCR4 by these viruses likely has profound effects on viral host range and correlates with the evolution of immunodeficiency. Stromal cell-derived factor-1 (SDF-1), the ligand for CXCR4, can inhibit infection by CXCR4-dependent viruses. To understand the mechanism of this inhibition, we used a monoclonal antibody that is specific for CXCR4 to analyze the effects of phorbol esters and SDF-1 on surface expression of CXCR4. On human T cell lines SupT1 and BC7, CXCR4 undergoes slow constitutive internalization (1.0% of the cell surface pool/min). Addition of phorbol esters increased this endocytosis rate >6-fold and reduced cell surface CXCR4 expression by 60 to 90% over 120 min. CXCR4 was internalized through coated pits and coated vesicles and subsequently localized in endosomal compartments from where it could recycle to the cell surface after removal of the phorbol ester. SDF-1 also induced the rapid down modulation (half time approximately 5 min) of CXCR4. Using mink lung epithelial cells expressing CXCR4 and a COOH-terminal deletion mutant of CXCR4, we found that an intact cytoplasmic COOH-terminal domain was required for both PMA and ligand-induced CXCR4 endocytosis. However, experiments using inhibitors of protein kinase C indicated that SDF-1 and phorbol esters trigger down modulation through different cellular mechanisms. SDF-1 inhibited HIV-1 infection of mink cells expressing CD4 and CXCR4. The inhibition of infection was less efficient for CXCR4 lacking the COOH-terminal domain, suggesting at least in part that SDF-1 inhibition of virus infection was mediated through ligand-induced internalization of CXCR4. Significantly, ligand induced internalization of CXCR4 but not CD4, suggesting that CXCR4 and CD4 do not normally physically interact on the cell surface. Together these studies indicate that endocytosis can regulate the cell-surface expression of CXCR4 and that SDF-1-mediated down regulation of cell-surface coreceptor expression contributes to chemokine-mediated inhibition of HIV infection.

Influences on infant-feeding beliefs and practices in an urban aboriginal community

The Victorian Aboriginal Health Service initiated a project to increase breast-feeding rates in the Melbourne Aboriginal community. The results of focus-group discussions on infant-feeding experiences and beliefs provided a wealth of information for the design of appropriate interventions. Most women wanted and expected to breast-feed. Some chose artificial feeding because of embarrassment, a belief that it is as good as breast-feeding, or perceptions that breast-feeding is painful and inconvenient. The most common reasons that women stopped breast-feeding were sore nipples, worries about their supply of milk and tiredness. Lack of knowledge, hospital practices, lack of support and appropriate advice, and lack of confidence and self-esteem contributed to these problems. Disruption of the passing on of knowledge of healthy infant-feeding practices between generations is another cultural loss suffered by Aboriginal communities. Efforts to restore traditional rates of breast-feeding need to be under Aboriginal control and to take account of these influences.