Moderate Percentage Research Articles

Multicenter, prospective study of radiotherapy without surgery after AC followed by weekly paclitaxel for patients with inflammatory breast cancer: SBCCSG-04 study

10783 Background: Inflammatory breast cancer (IBC) is a rare and aggressive disease with a dismal outcome. It is still an open debate whether surgery is beneficial for patients with IBC. This study was conducted to evaluate treatment results when patients were treated by chemotherapy and radiotherapy (CRT) alone. Methods: 52 pts with nonmetastatic IBC were enrolled for a prospective registration trial from 9/01–11/04. A diagnosis required the presence of erythema, ridging, or peau d’orange, with or without dermal lymphatic invasion (DLI). All patients were invited to participate for an experimental protocol; 4 cycles of AC and 12 cycles of weekly paclitaxel (80 mg/m2) followed by radiotherapy. In patients who did not agree to the protocol, the decision about treatment was left to the patients/investigators. The primary endpoint was distant-disease-free survival, and the further endpoints were locoregional relapse (LR) and overall survival. Results: The mean follow-up was 25.7 months. 24 pts (46.2%) were planned for the protocol, but one pt (4%) was receipt surgery. Otherwise, 18 (64%) out of 28 pts have accepted mastectomy. The 2-year distant-disease-free, LR, and overall survival in patients treated with and without the protocol was 35.2 vs 61.0% (HR = 2.4, 1.1–5.3) and 55.2 vs 83.6% (HR = 2.9, 1.1–7.8), respectively. Surgery was not associated with the risk of LR (p = 0.48). There was marginally worse prognosis in patients with DLI. Conclusions: There was a limitation because this comparison had not been conducted a randomized fashion. However, CRT alone would be a feasible treatment schedule for a moderate percentage of patients with IBC. No significant financial relationships to disclose.

Interleukin-10, age and acute lung injury genetics: the action is in the interaction

Acute lung injury (ALI) and its more severe form, acute respiratory distress syndrome (ARDS), are important public health issues, and both incidence and mortality increase with age 1. Given that only a moderate percentage of individuals with the same level of exposure develop ALI/ARDS, it is logical to investigate whether inherent interindividual variation will, in part, determine the risk of ALI/ARDS. Better understanding of the genetic factors influencing both risk of developing ALI/ARDS and outcomes following ALI/ARDS may aid in the identification of high-risk individuals, suggest areas for laboratory research and lead to the development of more specific, targeted pharmacogenomic strategies for treatment and prevention 2. Research on the genetic epidemiology of ALI/ARDS is in its early stages. Studies in this area have either used physiological hypotheses (including angiotensin-converting enzyme and surfactant proteins) 3, 4 or bioinformatics approaches based on animal experiments to select candidate genes 5. In this issue of the European Respiratory Journal , Gong et al . 6 provide an important contribution to understanding the genetic aetiology of ARDS and outcomes following ARDS. In a well-constructed cohort study, the authors report an association of an interleukin (IL)-10 promoter polymorphism with ALI/ARDS that differed by strata of age. Gong et al . 6 should be commended on several important strengths of their study. First, the large nested case–control design ensured that all non-ARDS subjects were drawn from the same at-risk cohort, minimising the bias due …

Development and communication of written ethics policies on euthanasia in Catholic hospitals and nursing homes in Belgium (Flanders)

Objective To describe whether and how Catholic hospitals and nursing homes in Belgium (Flanders) have developed written ethics policies on euthanasia and communicated these policies to their employees, patients, and patient's relatives. Methods A cross-sectional mail survey of general directors of Catholic hospitals and nursing homes in Belgium (Flanders). Results Of the 298 targeted institutions, 81% of hospitals and 62% of nursing homes returned complete questionnaires. A high percentage of Catholic hospitals (79%) and a moderate percentage of nursing homes (30%) had written ethics policies on euthanasia. Both caregivers and healthcare administrators were involved in the development and approval of these policies. Physicians and nurses were best informed about the policies. More than half of the nursing homes (57%) took the initiative to inform both residents and relatives about the policies, while only one hospital did so. Conclusion The high prevalence of written ethics policies on euthanasia in Flemish Catholic hospitals may reflect the concern of healthcare administrators to maintain the quality of care for patients requesting euthanasia. However, the true contribution of these policies to quality end-of-life care and to supporting caregivers remains unknown and needs further research. Practice implications Legislation and centrally developed guidelines might influence healthcare institutions to develop ethics policies.

Disparities in Depression Treatment for Latinos and Site of Care

This study examined the impact of patient characteristics and source of care on differences between whites and Latinos in use and quality of depression treatment in managed primary care settings. Data were examined for 1,175 patients (398 Latinos and 777 whites) in 46 managed primary care practices who screened positive for probable depressive disorder. Patient baseline assessments were used to compile sociodemographic and clinical characteristics and to derive variables for receipt of any depression care and depression care that met minimum guidelines (antidepressant use or specialty counseling) in the past six months. Clinics were classified by the percentage of their patient population that consisted of Latinos to determine whether patients in highly Latino clinics reported lower rates of care. Predictors of use and quality of depression care were examined by using logistic regression. Rates of receipt of any depression care and guideline-level depression care were low, and Latinos were less than half as likely as whites to receive such care, even after the analyses controlled for independent predictors (that is, younger age, higher educational level, current unemployment, more comorbid medical illness, and a diagnosis of a depressive or anxiety disorder). The likelihood of receiving any care or care that met guidelines did not significantly vary according to whether clinics served a low, moderate, or high percentage of Latinos. Disparities in depression care for Latinos were not attributable to sociodemographic and clinical characteristics, and they were not attributable to receiving care in clinics that served ethnically similar or dissimilar clientele. These findings suggest that other patient or provider factors may be responsible.

Evaluating the Molecular Mechanics Poisson−Boltzmann Surface Area Free Energy Method Using a Congeneric Series of Ligands to p38 MAP Kinase

The recently described molecular mechanics Poisson-Boltzmann surface area (MM-PBSA) method for calculating free energies is applied to a congeneric series of 16 ligands to p38 MAP kinase whose binding constants span approximately 2 orders of magnitude. These compounds have previously been used to test and compare other free energy calculation methods, including thermodynamic integration (TI), OWFEG, ChemScore, PLPScore, and Dock Energy Score. We find that the MM-PBSA performs relatively poorly for this set of ligands, yielding results much inferior to those from TI or OWFEG, inferior to Dock Energy Score, and not appreciably better than ChemScore or PLPScore but at an appreciably larger computational cost than any of these other methods. This suggests that one should be selective in applying the MM-PBSA method and that for systems that are amenable to other free energy approaches, these other approaches may be preferred. We also examine the single simulation approximation for MM-PBSA, whereby the required ligand and protein trajectories are extracted from a single MD simulation rather than two separate MD runs. This assumption, sometimes used to speed the MM-PBSA calculation, is found to yield significantly inferior results with only a moderate net percentage reduction in total simulation time.

Laser-Capture Microdissection: Refining Estimates of the Quantity and Distribution of Latent Herpes Simplex Virus 1 and Varicella-Zoster Virus DNA in Human Trigeminal Ganglia at the Single-Cell Level

There remains uncertainty and some controversy about the percentages and types of cells in human sensory nerve ganglia that harbor latent herpes simplex virus 1 (HSV-1) and varicella-zoster virus (VZV) DNA. We developed and validated laser-capture microdissection and real-time PCR (LCM/PCR) assays for the presence and copy numbers of HSV-1 gG and VZV gene 62 sequences in single cells recovered from sections of human trigeminal ganglia (TG) obtained at autopsy. Among 970 individual sensory neurons from five subjects, 2.0 to 10.5% were positive for HSV-1 DNA, with a median of 11.3 copies/positive cell, compared with 0.2 to 1.5% of neurons found to be positive by in situ hybridization (ISH) for HSV-1 latency-associated transcripts (LAT), the classical surrogate marker for HSV latency. This indicates a more pervasive latent HSV-1 infection of human TG neurons than originally thought. Combined ISH/LCM/PCR assays revealed that the majority of the latently infected neurons do not accumulate LAT to detectable levels. We detected VZV DNA in 1.0 to 6.9% of individual neurons from 10 subjects. Of the total 1,722 neurons tested, 4.1% were VZV DNA positive, with a median of 6.9 viral genomes/positive cell. After removal by LCM of all visible neurons on a slide, all surrounding nonneuronal cells were harvested and assayed: 21 copies of HSV-1 DNA were detected in approximately 5,200 nonneuronal cells, while nine VZV genomes were detected in approximately 14,200 nonneuronal cells. These data indicate that both HSV-1 and VZV DNAs persist in human TG primarily, if not exclusively, in a moderate percentage of neuronal cells.

Response of lactating cows to three supplemental fat sources as affected by forage in the diet and stage of lactation: a meta-analysis of literature

Research on fat supplementation has demonstrated that the production response of dairy cows to supplemental fats is highly variable, both among and within fat sources. Differential responses to dietary fats that have been observed when feeding the same type of fat to cows fed different basal diets suggests fat by diet interactions occur. A summary of the available literature on the effects of fat supplementation on dry matter intake (DMI), milk yield and composition and nutrient digestion in dairy cattle since 1980 was performed. Fat sources examined were tallow, calcium salts of palm fatty acids (CaS), and selected hydrolyzed tallow fatty acids (SHTFA). Responses of lactating dairy cows to increased levels of added fat were evaluated as affected by fat source and the main forage in the basal diet. Effect of stage of lactation on the response to fat supplementation was also examined. Decreased DMI and modest milk yield increases occurred for the fat sources evaluated. Different responses to supplemental fats were observed depending on the main forage in the basal diet. Feeding tallow with diets high in corn silage decreased DMI and milk fat yield, with no effect on milk production. However, a moderate positive milk production response was observed when tallow was fed with alfalfa-based diets or diets with corn silage and alfalfa in similar proportions. Supplemental SHTFA resulted in moderate positive milk fat percentage and yield response, regardless of the main forage in the basal diet. A significant positive milk yield response was observed when CaS was fed with diets high in corn silage, but not with alfalfa-based diets or diets with alfalfa and corn silage in similar proportions. An interaction between stage of lactation and amount of supplemental fat was observed, with supplemental fat increasing milk production of early lactation cows but not that of mid lactation cows, where milk fat depression occurred. Interactions between fat type and characteristics of the basal diets must be identified in order to predict the production responses of dairy cows to supplemental dietary fats.

Evaluation of beef cattle genotypes and estimation of direct and maternal genetic effects in a tropical environment. 3. Fertility and calf survival traits

Data from a crossbreeding experiment were analysed to compare various breeds in a tropical environment. Data included male fertility [scrotal circumference at yearling age (YSC) and at 18 months of age (FSC)], female fertility [calving success (CS) and days to calving (DTC)], and calf survival [survival of calf up to 1 week after birth (WKS) and up to weaning (PWS)] traits. Male fertility traits were analysed as traits of the progeny generation, whereas female fertility and calf survival traits were analysed as traits of the dam (parental generation). Tropically adapted British breed bulls and taurine crossbreds (British × Sanga) had higher YSC and FSC than Zebu and its crosses when adjusted for their body weights. Large negative direct and maternal additive effects on scrotal circumference for Zebu relative to the British breed also suggested reduced scrotal circumference and fertility in Zebu and Zebu-derived crosses. Direct dominance effects for YSC and FSC were only significant when an adjustment for body weight was not included in the model, emphasising that the heterosis observed was only due to the increased body weight. In general, CS was higher in non-lactating cows and maiden heifers than in lactating cows. The advantage to crossbred genotypes was more pronounced in lactating cows. Among lactating purebreds, CS was significantly (P < 0.05) higher in Belmont Adaptaur (Hereford–Shorthorn, HS) than in Belmont Red (AX), Belmont Brahman cross (BX), and Brahman (Bh). Lactating crossbreds with a common dam breed of HS, AX, BX, and Bh had 19, 33, 21, and 14% greater CS than their respective purebreds. Boran-sired crossbred dams had higher CS than Brahman-sired crossbreds, indicating higher fertility levels of Borans. Significant direct dominance effect for CS in lactating taurine–indicine crosses and in non-lactating taurine–taurine crosses signifies the importance of use of appropriate breed crosses in improving female fertility. Significantly negative (desirable) direct dominance effects for DTC in indicine–indicine and taurine–indicine crosses suggest an advantage from crossbreeding in achieving early calvings. High mortalities were recorded in calves born to HS dams from matings with Brahman bulls due to dystocia. This resulted in low WKS and PWS for HS dam breeds. All additive and dominance effects for calf survival traits were non-significant except for the direct dominance effect in taurine–indicine crosses for PWS. Moderate percentage heterosis estimates in lactating cows for CS and desirable, significant, but low percentage heterosis estimates for DTC were observed. Percentage heterosis estimates for calf survival traits were low and non-significant.

Ovalbumin-Induced Airway Inflammation and Fibrosis in Mice Also Exposed to Ozone

A murine model of allergen-induced airway inflammation was used to examine the effects of exposure to ozone on airway inflammation and remodeling. Sensitized BALB/c mice were exposed to ovalbumin aerosol for 4 wk before and after 2 wk of exposure to either 0.2 ppm or 0.5 ppm ozone. Other groups of mice were exposed to ovalbumin aerosol for 6 wk with continuous concurrent exposure to ozone during wk 1–6, or during intermittent concurrent exposure to ozone. Lung inflammation was measured by quantitative differential evaluation of lung lavage cells and by histological evaluation of stained lung sections. Alterations in lung structure (airway fibrosis) were evaluated by quantitative biochemical analysis of microdissected airways. The same total number of cells was observed in lavage fluid from animals exposed for 4 wk to ovalbumin alone or to ovalbumin for 4 wk immediately before or after exposure to 2 wk of 0.2 or 0.5 ppm ozone. Mice exposed to ovalbumin for 6 wk with concurrent exposure to either 0.2 ppm or 0.5 ppm ozone during wk 3–6 had a significant decrease in the total number of cells recovered by lavage. Values as low as 7% of the cell number found in mice exposed to ovalbumin aerosol alone were observed in the mice exposed to ovalbumin plus 0.2 ppm ozone during wk 3–6. There were significant differences in the cell differential counts in the lavage fluid from mice exposed to ovalbumin alone as compared with values from mice exposed to ovalbumin and ozone under all of the protocols studied. When ozone was given for 2 wk prior to ovalbumin exposure (Experiment 1), there were a high percentage of macrophages and low percentages of lymphocytes and eosinophils in the lung lavage. When ozone was given for 2 wk after ovalbumin exposure (Experiment 2), there were a moderate percentage of macrophages, a low percentage of eosinophils, and a high percentage of lymphocytes in the lung lavage. When ozone and ovalbumin were given simultaneously (Experiments 3 and 4), there were a high percentage of macrophages in the lavage with 0.2 ppm ozone and a high percentage of eosinophils. Ozone appears to antagonize the specific inflammatory effects of ovalbumin exposure, especially when given before or during exposure to ovalbumin. Airway remodeling was examined by two different quantitative methods. None of the groups exposed concurrently to ovalbumin and ozone had a significant increase in airway collagen content as compared to the matched groups of mice exposed to ovalbumin alone. The findings were consistent with an additive response of mice to simultaneous exposure to ovalbumin and ozone. Ozone exposure alone for 6 wk did not affect the number of goblet cells in the airways, while mice exposed to ovalbumin aerosol alone for 6 wk had about 25% goblet cells in their conducting airways. Concurrent exposure to ovalbumin and 0.2 ppm ozone caused significant increases in goblet cells (to 43% of total cells) in the conducting airways of the exposed mice. We conclude that when mice with allergen-induced airway inflammation induced by ovalbumin are also exposed to ozone, the lung inflammatory response may be modified, but that this altered response is dependent on the sequence of exposure and the concentration of ozone to which they are exposed. At the concentrations of ozone tested, we did not see changes in airway fibrosis. However, goblet-cell hyperplasia appeared to be increased in mice exposed concurrently to ovalbumin and 0.2 ppm ozone.

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Aggressive lipid management for cardiovascular prevention: evidence from clinical trials.

Epidemiologic evidence shows that elevated serum cholesterol, specifically low-density lipoprotein cholesterol (LDL-C), increases the risk of coronary heart disease (CHD). Moreover, large-scale intervention trials demonstrate that treatment with HMG-CoA reductase inhibitors (statins), the most effective drug class for lowering LDL-C, significantly reduces the risk of CHD events. Unfortunately, only a moderate percentage of hypercholesterolemic patients are achieving LDL-C targets specified by the National Cholesterol Education Program (NCEP), in part because clinicians are not effectively titrating medications as needed to achieve LDL-C goals. Recent evidence suggests that more aggressive LDL-C lowering may provide greater clinical benefit, even in individuals with moderately elevated serum cholesterol levels. Furthermore, recent studies suggest that statins have cardioprotective effects in many high-risk individuals, including those with baseline LDL-C <100 mg/dl. High-density lipoprotein cholesterol (HDL-C) was recognized by the NCEP-Adult Treatment Panel II (ATP II) as a negative risk factor for CHD. The NCEP-ATP III guidelines have also reaffirmed the importance of HDL-C by increasing the low HDL-C designation from <35 to <40 mg/dl as a major risk factor for CHD. Similarly, triglyceride control will play a larger role in dyslipidemia management. As more clinicians effectively treat adverse lipid and lipoprotein cardiovascular risk factors, patients will likely benefit from reductions in cardiovascular events.

Conservation and control strategies for the wolf ( Canis lupus) in western Europe based on demographic models

Securing the long-term acceptance of large carnivores such as the wolf ( Canis lupus) in Europe and North America raises a difficult challenge to conservation biologists: planning removals to reduce depredations on livestock while ensuring population viability. We use stochastic-stage-structured population models to investigate wolf population dynamics and to assess alternative management strategies. Among the various management strategies advocated by agencies, zoning that involves eliminating wolves outside a restricted area should be designed with caution, because probabilities of extinction are extremely sensitive to the maximum number of packs that a zone can support and to slight changes in stage specific survival probabilities. In a zoned population, viability is enhanced more by decreasing mortality rates in all classes than by increasing wolf zone size. An alternative to zoning is adaptive management, where there is no limit on pack number but population control can be operated whenever some predefined demographic conditions are met. It turns out that an adaptive management strategy that removes a moderate percentage (10%) of the population following each year of more than 5% of total population growth would provide visible actions addressing public concerns while keeping extinction probability low. To cite this article: G. Chapron et al., C. R. Biologies 326 (2003).

Botulinum toxin treatment of urethral and bladder dysfunction.

Botulinum toxin (BTX) is the most lethal naturally occurring toxin known to mankind. Injection of BTX into the urethral sphincter or bladder is an effective treatment for lower urinary tract dysfunction. We reviewed the literature on the mechanisms of action and clinical efficacy of BTX treatment in urologic diseases, with a focus on lower urinary tract dysfunction. Injection of BTX is safe and effective in the treatment of detrusor-sphincter dyssynergia, non-neurogenic pelvic floor spasticity, and refractory overactive bladder. Urodynamic assessment after sphincter injection with BTX reveals a decrease of bladder voiding pressure, urethral pressure profile, and post-void residual urine. An increase of the functional bladder capacity and a decrease of the bladder voiding pressure can be seen after bladder injection with BTX. Clinical improvement was found in a moderate percentage of treated patients in most reported series and lasted for 3 to 14 months without significant adverse effects. In addition, BTX-A treatment inhibits afferent-nerve-mediated bladder contraction. This analgesic effect may expand the application of BTX in the localized genitourinary tract pain syndrome, such as interstitial cystitis and prostatodynia. In conclusion, application of BTX is a promising treatment for lower urinary tract dysfunction with profound basic and clinical implications.

Sexuality Issues in Adolescents with a Chronic Neurological Condition

Substantial progress in the medical treatment of individuals with spina bifida (SB) has increased the numbers who survive into adolescence and adulthood. However, sexual health in this population has not received much attention. This study explored the knowledge (SB Sexuality Knowledge Scale), worries (SB Worries Scale), romantic appeal (from Harter's Self-Perception Scale), and access to sexuality information of a sample of 60 adolescents from a midwestern state. Study participants reported having sexual feelings like their peers, and they knew they could contract sexually transmitted diseases (STDs) if they were sexually active. However, only a moderate percentage was aware that women with SB are fertile, that adolescent women with SB should take a multivitamin with folic acid, and that latex-free condoms should be used by most adolescents with SB. They did not worry about their ability to make friends; however, these adolescents reported low levels of perceived romantic appeal and they worried about sexuality issues. These sexuality issues were not correlated to measures of SB neurological severity. Although over 50% reported having discussed sexuality with a health professional, 29% reported no one discussed sexuality and SB with them. Data from this study can affect the way health care providers and educators conduct sexuality education in health care and school settings.

Preservice Teachers' Perceptions of Service-Learning

The study explored preservice teachers' experiences and perceptions of implementation of service-learning into the teacher preparation progrcun and its use as a teaching methodology in their own teaching. Through quantitative data generated from a survey instrument, the concept of a service-learning as a viable teaching method was well received. After an initial introduction to the concept of service-learning methhodology, a moderate percentage of preservice teachers stated they would likely use it in their own teaching. Data suggests no systematic relationship between certainty of teaching as a career choice and perceptions of service-learning. However, the data does suggest significant differences in the types of service-learning projects implemented and the grade the preservice teacher was expected to teach.

Dormancy‐breaking and germination requirements for seeds of Symphoricarpos orbiculatus (Caprifoliaceae)

Fruits (drupes) of Symphoricarpos orbiculatus ripen in autumn and are dispersed from autumn to spring. Seeds (true seed plus fibrous endocarp) are dormant at maturity, and they have a small, linear embryo that is underdeveloped. In contrast to previous reports, the endocarp and seed coat of S. orbiculatus are permeable to water; thus, seeds do not have physical dormancy. No fresh seeds germinated during 2 wk of incubation over a 15°/6°-35°/20°C range of thermoperiods in light (14-h photoperiod); gibberellic acid and warm or cold stratification alone did not overcome dormancy. One hundred percent of the seeds incubated in a simulated summer → autumn → winter → spring sequence of temperature regimes germinated, whereas none of those subjected to a winter → spring sequence did so. That is, cold stratification is effective in breaking dormancy only after seeds first are exposed to a period of warm temperatures. Likewise, embryos grew at cold temperatures only after seeds were exposed to warm temperatures. Thus, the seeds of S. orbiculatus have nondeep complex morphophysiological dormancy. As a result of dispersal phenology and dormancy-breaking requirements, in nature most seeds that germinate do so the second spring following maturity; a low to moderate percentage of the seeds may germinate the third spring. Seeds can germinate to high percentages under Quercus leaf litter and while buried in soil; they have little or no potential to form a long-lived soil seed bank.

Evaluation by explicit criteria of the use of total hip joint replacement

To evaluate the appropriateness of the use of total hip replacement (THR) using explicit criteria developed by an expert panel. Patients with a diagnosis of osteoarthritis who were undergoing THR in five public hospitals in Spain were included consecutively in the study during a 1-yr period. The appropriateness of the indication was judged by explicit criteria developed using a mutidisciplinary approach. Complications were measured 3 months after surgery. One year after discharge, pain, functional limitation and general health were measured. After evaluation of 583 patients, 82 (13.6%) were considered to have undergone inappropriate procedures, and for 279 (46.2%) patients indication for the procedure was considered uncertain. Differences were found in the rate of appropriateness among some centres. One year after discharge, the perception of general health was slightly better in those patients who had been judged to have undergone an appropriate procedure. The study identified a moderate percentage of inappropriately performed THR. When considered together with those cases that were judged to have uncertain indications, the results indicate that further studies should be done to identify patients who may have an inadequate benefit:risk ratio from this procedure.

Factors Affecting the Transmission and Spread of Sugarcane yellow leaf virus.

Sugarcane, Saccharum spp. hybrid, is widely infected in the United States and many other countries with a yellowing and stunting disease called sugarcane yellow leaf syndrome. The causal agent, Sugarcane yellow leaf virus (ScYLV), is a Polerovirus of the Luteoviridae family. In this study, it was transmitted by the sugarcane aphid, Melanaphis sacchari, and also by the corn leaf aphid, Rhopalosiphum maidis, and the rice root aphid, R. rufiabdominalis. Two other aphids that infest sugarcane in Hawaii did not transmit the virus. Some Hawaiian sugarcane cultivars are susceptible to ScYLV, while others remain virus-free in the field. The latter were not infected when inoculated with viruliferous M. sacchari. Virus-free plants of susceptible cultivars were produced through apical meristem culture and were readily reinfected by viruliferous M. sacchari. They were also quickly reinfected when planted in a field in proximity to other infected sugarcane naturally infested with M. sacchari. Sugarcane cultivars are hybrids of several Saccharum species. In a field-grown collection of Saccharum and related species, 11 to 71% of the clones of four of the species were infected with ScYLV. None of the related genus Erianthus plants were infected, but four clones were infected experimentally by aphid inoculation. A low to moderate percentage of corn, rice, and sorghum seedlings became infected when inoculated with ScYLV, but barley, oats, and wheat proved to be very susceptible. None of seven weeds common in sugarcane fields were infected with ScYLV.

Nitrogen Sorption Studies of Silica Particles Obtained in Emulsion and Microemulsion Media

The internal surface structures of silica aerogel particles synthesized using different catalysts in emulsion and microemulsion media have been investigated by means of N2 adsorption and desorption isotherms. Surface fractal dimensions have been computed using different methods: Frankel–Halsey–Hill plots of the adsorption isotherms, the thermodynamic fractal isotherm equation, and a modification of the thermodynamic fractal isotherm equation. Silica aerogels synthesized in emulsion media with an acidic catalyst have a high specific surface area without micropores and show two separate ranges of scales where the surface fractal dimensions are different and constant. Silica aerogels synthesized in emulsion media with a basic catalyst have a moderate specific surface area with a high percentage of micropores and show constant surface fractal dimensions over a larger range. Silica aerogels synthesized in microemulsion media with a basic catalyst have a low specific surface area with a moderate percentage of micropores and show a moderate range of scales over which the surface fractal dimension is constant. Analyses by both the thermodynamic and modified thermodynamic methods give similar ranges of the surface fractal dimensions of the silica particles.

EVALUATION OF THE APPROPRIATENESS OF HIP JOINT REPLACEMENT TECHNIQUES

To evaluate the appropriateness of the use of hip joint replacements (HJRs) using explicit criteria developed by an expert panel. Observational study. Nine hundred ninety-seven patients from five hospitals with a diagnosis of osteoarthritis, avascular necrosis, hip fracture, or revision who were undergoing HJR were consecutively included in the study during a 1-year period. The appropriateness of the indication was judged by explicit criteria. Complications were recorded at the time of the intervention and 3 months postoperatively. Of the 1,030 interventions, 604 were for osteoarthritis, 31 avascular necrosis, 191 fractures, and 204 revisions. No differences were found among the hospitals for the main clinical and patient variables. Indications for surgery were considered appropriate in 59% of cases, uncertain in 32%, and inappropriate in 8%, mainly in the osteoarthritis group. Differences were found in the rates of appropriateness among some centers. The complication rate did not differ among the groups based on the level of appropriateness of the procedure. The appropriate use of HJR, as measured by the criteria established by the panel, identified a moderate percentage of inappropriate indications. Those equivocal and inappropriate cases demand further studies to identify patients with an adequate risk-to-benefit ratio from this procedure.