Herbivory, plant traits and nectar chemistry interact to affect the community of insect visitors and pollination in common milkweed, Asclepias syriaca.

Herbivory can alter plant fitness directly through changing reproductive allocation and indirectly through changing pollinator identity or behavior. Common milkweed is a plant of conservation concern with an inducible chemical defense that is also an important nectar resource. In this study, we aim to understand how herbivory severity and plant traits, including morphology and nectar chemistry, interact to affect insect visitation and pod production in common milkweed. We conducted pollinator watches on plants with experimentally varied herbivory severity and quantified insect frequency and visit length as a response to nectar chemistry, ramet height, number of inflorescences, number of flowers per inflorescence and percent tissue removed. We also quantified pollinator effectiveness and importance. Increased herbivory severity reduced floral displays, including fewer inflorescences and fewer flowers per inflorescence. A reduced floral display was correlated with reduced sucrose, fructose and glucose and resulted in a reduced number and species richness of insect visitors. Fewer flowers per inflorescence reduced the frequency of bumble bee and fly visitors, which were two important pollinators. Although honeybees, flies, small bees, soldier beetles and bumble bees were equally effective pollinators, only bumble bee frequency was positively correlated with pod production. The differences in pollinator visitation have the potential to create diversifying selection on plant floral traits, many of which are also affected by herbivores. This research demonstrates potentially conflicting selection pressures between native and non-native pollinators as well as non-native herbivores.

Temporal Dynamics of Wheat Blast Epidemics and Disease Measurements Using Multispectral Imagery.

Wheat blast is a devastating disease caused by the Triticum pathotype of Magnaporthe oryzae. M. oryzae Triticum is capable of infecting leaves and spikes of wheat. Although symptoms of wheat spike blast (WSB) are quite distinct in the field, symptoms on leaves (WLB) are rarely reported because they are usually inconspicuos. Two field experiments were conducted in Bolivia to characterize the change in WLB and WSB intensity over time and determine whether multispectral imagery can be used to accurately assess WSB. Disease progress curves (DPCs) were plotted from WLB and WSB data, and regression models were fitted to describe the nature of WSB epidemics. WLB incidence and severity changed over time; however, the mean WLB severity was inconspicuous before wheat began spike emergence. Overall, both Gompertz and logistic models helped to describe WSB intensity DPCs fitting classic sigmoidal shape curves. Lin's concordance correlation coefficients were estimated to measure agreement between visual estimates and digital measurements of WSB intensity and to estimate accuracy and precision. Our findings suggest that the change of wheat blast intensity in a susceptible host population over time does not follow a pattern of a monocyclic epidemic. We have also demonstrated that WSB severity can be quantified using a digital approach based on nongreen pixels. Quantification was precise (0.96 < r> 0.83) and accurate (0.92 < ρ > 0.69) at moderately low to high visual WSB severity levels. Additional sensor-based methods must be explored to determine their potential for detection of WLB and WSB at earlier stages.

Growth and form of a self-constructing tube network.

When a small amount of liquid is quickly injected into another liquid with similar density, the fluid jet usually does not propagate very far. However, when the two solutions chemically react to form a flexible membrane at their interface, then structures that are long and branching can form. Here, we describe the tube networks produced when a small amount of AlCl3 solution is quickly injected into a NaOH solution. Single straight tubes do not occur, but straight tubular "stems" with 2-5 "branches" are observed. The branches emerge relatively symmetrically from the stem at a common branching junction. These structures can have a ratio of propagation distance to stem width as large as 50. The stem and branches grow by the stretching of the membrane sheathing the closed tube system. These tube networks occasionally exhibit the spontaneous creation of new branches at a junction and also the splitting of a branching junction. A model explains why the branches occur, why they are symmetric around the central stem, and why the initial growth speed is insensitive to the flow rate.

Integrating Spectroscopy with Potato Disease Management.

Spectral phenotyping is an efficient method for the nondestructive characterization of plant biochemical and physiological status. We examined the ability of a full range (350 to 2,500 nm) of foliar spectral data to (i) detect Potato virus Y (PVY) and physiological effects of the disease in visually asymptomatic leaves, (ii) classify different strains of PVY, and (iii) identify specific potato cultivars. Across cultivars, foliar spectral profiles of PVY-infected leaves were statistically different (F = 96.1, P ≤ 0.001) from noninfected leaves. Partial least-squares discriminate analysis (PLS-DA) accurately classified leaves as PVY infected (validation κ = 0.73) and the shortwave infrared spectral regions displayed the strongest correlations with infection status. Although spectral profiles of different PVY strains were statistically different (F = 6.4, P ≤ 0.001), PLS-DA did not classify different strains well (validation κ = 0.12). Spectroscopic retrievals revealed that PVY infection decreased photosynthetic capacity and increased leaf lignin content. Spectral profiles of potato cultivars also differed (F = 9.2, P ≤ 0.001); whereas average spectral classification was high (validation κ = 0.76), the accuracy of classification varied among cultivars. Our study expands the current knowledge base by (i) identifying disease presence before the onset of visual symptoms, (ii) providing specific biochemical and physiological responses to disease infection, and (iii) discriminating between multiple cultivars within a single plant species.

Behavioral Responses of Pityophthorus juglandis (Coleoptera: Curculionidae: Scolytinae) to Volatiles of Black Walnut and Geosmithia morbida (Ascomycota: Hypocreales: Bionectriaceae), the Causal Agent of Thousand Cankers Disease.

Thousand cankers disease (TCD) is a pest complex formed by the association of the walnut twig beetle (WTB), Pityophthorus juglandis Blackman (Coleoptera: Curculionidae: Scolytinae), with the fungal pathogen Geosmithia morbida Kolarík, Freeland, Utley and Tisserat (Ascomycota: Hypocreales: Bionectriaceae). Current monitoring and detection efforts for WTB rely on a pheromone lure that is effective over a limited distance while plant- and fungal-derived volatiles that may facilitate host location remain poorly understood. In this study, we test the hypothesis that adult beetles are attracted to volatiles of black walnut, Juglans nigra L. (Juglandaceae), and the pathogen, G. morbida. We measured the response of beetles to head-space volatiles collected from leaves and stems of 12 genotypes of black walnut and found genotypic variation in the attractiveness of host trees to adult WTB. Volatile profiles of the most attractive genotypes contained more α-pinene and ß-pinene, and adult beetles were attracted to both of these compounds in olfactometer bioassays. In bioassays, we also demonstrated that adult WTB are attracted to volatiles of G. morbida. These findings suggest that, in addition to the aggregation pheromone, dispersing WTB potentially use host plant and fungal volatiles to locate suitable larval hosts. Finally, we conducted a field experiment to determine the extent to which ethanol, a common attractant for bark beetles, and limonene, a known bark beetle repellent, influence the behavior of adult WTB to pheromone-baited traps. Although ethanol did not increase trap capture, WTB were repelled by limonene, suggesting that this compound could be used to manipulate and manage WTB populations.

Preparation, Biochemical Analysis, and Structure Determination of SET Domain Histone Methyltransferases.

In eukaryotes, several lysine residues on histone proteins are methylated. This posttranslational modification is linked to a myriad of nuclear-based transactions such as epigenetic inheritance of heterochromatin, regulation of gene expression, DNA damage repair, and DNA replication. The majority of the enzymes responsible for writing these marks onto chromatin belong to the SET domain family of histone lysine methyltransferases. Although they often share important structural features, including a conserved catalytic domain, SET domain enzymes use different mechanisms to achieve substrate recognition, mono-, di-, or trimethylate lysine residues and some require other proteins to achieve maximal methyltransferase activity. In this chapter, we summarize our efforts to purify, crystallize, and enzymatically characterize SET domain enzymes with a specific focus on the histone H3K27 monomethyltransferase ATXR5.

Insect herbivory alters impact of atmospheric change on northern temperate forests.

Stimulation of forest productivity by elevated concentrations of CO2 is expected to partially offset continued increases in anthropogenic CO2 emissions. However, multiple factors can impair the capacity of forests to act as carbon sinks; prominent among these are tropospheric O3 and nutrient limitations(1,2). Herbivorous insects also influence carbon and nutrient dynamics in forest ecosystems, yet are often ignored in ecosystem models of forest productivity. Here we assess the effects of elevated levels of CO2 and O3 on insect-mediated canopy damage and organic matter deposition in aspen and birch stands at the Aspen FACE facility in northern Wisconsin, United States. Canopy damage was markedly higher in the elevated CO2 stands, as was the deposition of organic substrates and nitrogen. The opposite trends were apparent in the elevated O3 stands. Using a light-use efficiency model, we show that the negative impacts of herbivorous insects on net primary production more than doubled under elevated concentrations of CO2, but decreased under elevated concentrations of O3. We conclude that herbivorous insects may limit the capacity of forests to function as sinks for anthropogenic carbon emissions in a high CO2 world.

Long-term exposure to elevated CO2 and O3 alters aspen foliar chemistry across developmental stages.

Anthropogenic activities are altering levels of greenhouse gases to the extent that multiple and diverse ecosystem processes are being affected. Two gases that substantially influence forest health are atmospheric carbon dioxide (CO2 ) and tropospheric ozone (O3 ). Plant chemistry will play an important role in regulating ecosystem processes in future environments, but little information exists about the longitudinal effects of elevated CO2 and O3 on phytochemistry, especially for long-lived species such as trees. To address this need, we analysed foliar chemical data from two genotypes of trembling aspen, Populus tremuloides, collected over 10 years of exposure to levels of CO2 and O3 predicted for the year 2050. Elevated CO2 and O3 altered both primary and secondary chemistry, and the magnitude and direction of the responses varied across developmental stages and between aspen genotypes. Our findings suggest that the effects of CO2 and O3 on phytochemical traits that influence forest processes will vary over tree developmental stages, highlighting the need to continue long-term, experimental atmospheric change research.

Calphostin C-induced apoptosis is mediated by a tissue transglutaminase-dependent mechanism involving the DLK/JNK signaling pathway.

A role for tissue transglutaminase (TG2) and its substrate dual leucine zipper-bearing kinase (DLK), an upstream component of the c-Jun N-terminal kinase (JNK) signaling pathway, has been previously suggested in the apoptotic response induced by calphostin C. In the current study, we directly tested this hypothesis by examining via pharmacological and RNA-interference approaches whether inhibition of expression or activity of TG2, DLK and JNK in mouse NIH 3T3 fibroblasts and human MDA-MB-231 breast cancer epithelial cells affects calphostin C-induced apoptosis. Our experiments with the selective JNK inhibitor SP600125 reveal that calphostin C is capable of causing JNK activation and JNK-dependent apoptosis in both cell lines. Small interfering RNA-mediated depletion of TG2 alone strongly reduces calphostin C action on JNK activity and apoptosis. Consistent with an active role for DLK in this cascade of event, cells deficient in DLK demonstrate a substantial delay of JNK activation and poly-ADP-ribose polymerase (PARP) cleavage in response to calphostin C, whereas overexpression of a recombinant DLK resistant to silencing, but sensitive to TG2-mediated oligomerization, reverses this effect. Importantly, combined depletion of TG2 and DLK further alters calphostin C effects on JNK activity, Bax translocation, caspase-3 activation, PARP cleavage and cell viability, demonstrating an obligatory role for TG2 and DLK in calphostin C-induced apoptosis.

Post-operative radiochemotherapy for gastric cancer: adoption and adaptation.

AIMS: Intergroup study 0116 (INT-0116) showed an 11% absolute improvement in 3-year survival with post-operative radiochemotherapy for gastric cancer, but reported 33% severe acute GI toxicity using conventional simulation with large fields. We adapted the treatment using conformal radiotherapy techniques and assessed toxicity and outcome in 20 consecutive patients. METHODS: A conformal radiotherapy technique previously developed for gastric lymphoma was adapted to treat the target volume defined in INT-0116. The five-field plan used a large anterior field, plus asymmetrically matched upper AP:PA fields and lower lateral fields. Consecutive patients with ECOG PS 0-2 and stage IB-IV non-metastatic gastric cancer were treated with 5-FU (425 mg/m2 daily x 5 days) and leucovorin (20 mg/m2 daily x 5 days) for one cycle prior to and two cycles following concurrent radiation (45 Gy/25 fractions) with identical drug dosages on the first 4 and last 3 days of radiation. Acute toxicity was prospectively recorded weekly using RTOG and NCI common toxicity criteria. Patient charts were reviewed in November 2003 and late toxicity and outcome were recorded. RESULTS: Nineteen of 20 patients completed radiotherapy and 14 completed all chemotherapy cycles. One patient died of neutropenic sepsis. Maximum acute toxicity [grade (number)] was: 5(1), 4(0), 3(4), 2(10), 1(4), 0(1). There were two grade 1 late toxicities. Two-year overall survival is 70% (95% confidence interval: 50-90). CONCLUSIONS: Conformal radiotherapy may improve acute toxicity (25% grade 3 or greater toxicity as compared with 41% reported in INT-0116). Survival is comparable to that achieved in the INT-0116 treatment arm (approximately 60% at 2 years). INT-0116 results can be achieved outside a study setting; however, further efforts to improve treatment efficacy and minimize toxicity are warranted.

Anatomic landmarks to estimate the length of the diaphragm from chest radiographs: effects of emphysema and lung volume reduction surgery.

STUDY OBJECTIVES: To define anatomic landmarks that can be used to predict insertions of the diaphragm on chest radiographs and to estimate diaphragm length. DESIGN: Prospective clinical trial with a parallel group design. SETTING: Laboratory investigations in normal volunteers recruited by advertisement and in emphysema outpatients being evaluated for elective bilateral lung volume reduction surgery (LVRS). PATIENTS: Twenty-six normal subjects classified into young and older age groups, with a third group of 13 emphysema patients matched for age and sex with the older group. MEASUREMENTS: Identification and between-group comparisons were made of anatomic landmarks on anteroposterior and lateral chest radiographs obtained at total lung capacity. Predicted landmarks were generated from normal subjects. Within-subject and between-group comparisons were made of diaphragm length index (DLI) based on observed anatomic landmarks (DLIobs) and diaphragm length index based on predicted anatomic landmarks (DLIpred) at functional residual capacity. RESULTS: Anatomic landmarks were not different between the three groups or between male and female subjects, and were not different before and after LVRS in emphysema patients. No difference was found between DLIobs and DLIpred in normal subjects and emphysema patients, but both were smaller in emphysema patients than in normal subjects and increased after LVRS in emphysema patients. CONCLUSION: This study validates the use of anatomic landmarks to estimate DLI. Using these landmarks simplifies the determination of diaphragmatic lengths and could be a useful tool for the evaluation of the functional capacity of the diaphragm, and possibly as a prognostic indicator of patients who are candidates for LVRS.

Soft tissue sarcomas involving the pelvis.

BACKGROUND AND OBJECTIVES: Soft tissue sarcomas (STS) of the true pelvis are rare tumors and there is little information in the literature related to pelvic STS. The purposes of this review were to understand the anatomic extension of these tumors to better plan surgical treatment and to determine the outcome of these patients. METHODS: Eighteen consecutive patients presenting between 1987 and 1995 with soft tissue sarcomas involving the true pelvis were retrospectively reviewed at minimum follow-up of 18 months. Cross-sectional imaging was reviewed for each patient to determine the anatomical location of the lesions. RESULTS: The tumors were confined to the true pelvis in 4 patients, extended to the retroperitoneum in three cases, and extended to the thigh in 11 patients. Adjuvant radiation was administered to all but 2 patients who had received radiation to the region in the past and all patients underwent surgical resection (local resection in 13 patients and hindquarter amputation in 5 patients). Surgical resection had a high rate of morbidity and complications including positive resection margins in nine individuals. Of the 18 patients, 11 died at a mean time of 15.5 (2-58) months from surgery, 4 were alive with evidence of disease at a mean time of 44.3 (18-68) months, and 3 were alive with no evidence of disease at a mean time of 57 (43-71) months. CONCLUSIONS: Soft tissue sarcoma of the pelvis is fortunately a rare disease with a high risk of local and systemic disease progression despite treatment with irradiation and surgical resection.

Impact of a cost-sharing drug insurance plan on drug utilization among older people.

OBJECTIVES: In August 1996, the Régie de l'assurance-maladie du QuEbec (RAMQ), the government body responsible for medical insurance in the Canadian province of Quebec, introduced a cost-sharing drug insurance plan. Before this plan, individuals age 65 years and older had to pay Canadian (CDN)$2 per prescription, with the remaining cost paid by the RAMQ. With the new plan, beneficiaries may have to pay an amount between CDN$200 and CDN$925 per year, depending on their income. Concerned that this financial constraint imposed on older people might have an impact on the use of medications, we investigated whether the consumption of four classes of medications, antihypertensive agents, anticoagulants, nitrates, and benzodiazepines, was affected by the drug plan implementation. DESIGN: Time series models with pre/post comparison group. SETTING: Administrative computerized databases of the RAMQ. PARTICIPANTS: Random sample of Quebec residents age 65 years and older registered in the provincial drug plan between August 1992 and June 1997: 54,771 users of nitrates, 133,146 users of antihypertensive agents, 45,534 users of anti-coagulants, and 26,165 users of benzodiazepines. MEASUREMENTS: We modeled the monthly consumption of the medications under study between August 1992 and June 1996. Monthly drug consumptions predicted from the models were compared with those observed for the 13 months (August 1996 to August 1997) following the implementation of the new drug plan using 95% confidence intervals. The number of prescriptions dispensed served as an indicator for drug consumption. RESULTS: During the study period we observed a nonstatistically significant decrease in number of prescriptions of 5.1% for nitrates, 1.1% for antihypertensive agents, and 0.8% for benzodiazepines, and a nonstatistically significant increase of 1.6% for anticoagulants. CONCLUSION: Residents of Quebec age 65 years and older were not found to have reduced significantly their consumption of nitrates, antihypertensive agents, anticoagulants, and benzodiazepines during the 13 months that followed the implementation of a cost-sharing drug insurance plan.

Guidelines 2000 for colon and rectal cancer surgery.

BACKGROUND: Oncologic resection techniques affect outcome for colon cancer and rectal cancer, but standardized guidelines have not been adopted. The National Cancer Institute sponsored a panel of experts to systematically review current literature and to draft guidelines that provide uniform definitions, principles, and practices. METHODS: Methods were similar to those described by the American Society of Clinical Oncology in developing practice guidelines. Experts representing oncology and surgery met to review current literature on oncologic resection techniques for level of evidence (I-V, where I is the best evidence and V is the least compelling) and grade of recommendation (A-D, where A is based on the best evidence and D is based on the weakest evidence). Initial guidelines were drafted, reviewed, and accepted by consensus. RESULTS: For the following seven factors, the level of evidence was II, III, or IV, and the findings were generally consistent (grade B): anatomic definition of colon versus rectum, tumor-node-metastasis staging, radial margins, adjuvant R0 stage, inadvertent rectal perforation, distal and proximal rectal margins, and en bloc resection of adherent tumors. For another seven factors, the level of evidence was II, III, or IV, but findings were inconsistent (grade C): laparoscopic colectomy; colon lymphadenectomy; level of proximal vessel ligation, mesorectal excision, and extended lateral pelvic lymph node dissection (all three for rectal cancer); no-touch technique; and bowel washout. For the other four factors, there was little or no systematic empirical evidence (grade D): abdominal exploration, oophorectomy, extent of colon resection, and total length of rectum resected. CONCLUSIONS: The panel reports surgical guidelines and definitions based on the best available evidence. The availability of more standardized information in the future should allow for more grade A recommendations.

Predictors of persistence of use of the novel antidiabetic agent acarbose.

BACKGROUND: A carbose is the first of a new class of antidiabetic agents, the alpha-glucosidase inhibitors. This study characterizes and identifies predictors of persistence of use of acarbose. METHODS: Medical, pharmaceutical, and demographic records were extracted for 2 cohorts of patients (social assistance recipients and seniors) from the databases of Quebec's provincial health plan. Patients were eligible for inclusion if they had received their first dispensation of acarbose between August 1, 1996, and December 31, 1997. The observation period included at least 1 year before the first dispensation and a minimum of 4 months after. RESULTS: New users of acarbose included 216 social assistance recipients and 677 seniors who were followed up for 82 914 and 270 041 person-days, respectively. Median persistence with acarbose treatment was 83 days (95% confidence interval, 75-105 days) for social assistance recipients and 105 days (95% confidence interval, 90-119 days) for seniors. In both cohorts, treatment by an endocrinologist vs another physician predicted longer treatment persistence. In the seniors cohort, additional determinants of (earlier) treatment discontinuation included a higher initial daily dose, previous treatment with insulin, and consultation with a gastroenterologist after treatment initiation. CONCLUSIONS: New users of acarbose showed low persistence in 2 cohorts of beneficiaries of Quebec's provincial health plan. Prescribing specialist was an important predictor of persistence in seniors and the socially assisted. The importance of 4 additional factors in seniors only led to hypotheses concerning population differences in treatment expectations and in the occurrence and tolerance of adverse effects.

Malignant gastrointestinal stromal tumors of the small intestine: a review of 50 cases from a prospective database.

BACKGROUND: Malignant gastrointestinal stromal tumors (M-GIST) are rare mesenchymal tumors originating in the wall of the gastrointestinal (GI) tract. Previous studies have included limited numbers of patients, and most included malignant and benign cases from throughout the GI tract. We reviewed the experience of a single tertiary cancer care center with M-GIST of the small intestine only. METHODS: A prospective database identified all patients seen from 1989 to 1998. Clinical and pathological data, treatment, and outcome were analyzed. Overall median follow-up time was 24 months (range, 1-176 months). RESULTS: Fifty patients (31 male, 19 female) were identified. Mean age at diagnosis was 55 years. Disease was localized in 11 patients, locally advanced (invasion into adjacent organs/peritoneum) in 24 patients, perforated in 4 patients, multiple primary lesions in 2 patients, and distant metastases in 9 patients. All patients underwent resection, which was complete in 70%. Locoregional recurrence (LR) developed in 43% (median, 25 months), and distant metastases in 59% (median, 21 months) of patients at risk. At last follow-up, 14 patients were alive (6 disease-free), 2 had died disease-free, and 34 died with recurrent disease. Overall survival (OS) was similar for localized and locally advanced disease; OS also was similar for patients with multiple primaries and distant metastases at diagnosis. Patients were grouped into three stages: (I) patients with localized and locally advanced disease; (II) patients with perforated; and (III) patients with multiple primaries and distant metastases. Actuarial OS at 5 years was 41% (n = 50)--42% for those with complete resection and 8% for incomplete resection. Univariable analysis showed that earlier stage at diagnosis (P = .001) and completeness of resection (P = .004) predicted for longer OS. CONCLUSIONS: Most patients with M-GIST of the small intestine relapse following resection, but survival may be prolonged. In univariable analysis, stage at presentation and complete resection were significant prognostic variables for OS; grade was not significant. Localized and locally advanced M-GIST of the small intestine have a mean OS > 5 years. Complete resection should be the goal of initial surgical treatment.

Recent progress in the management of retroperitoneal sarcoma.

Retroperitoneal sarcomas (RPS) are rare tumours that typically present late and carry a poor prognosis even following grossly complete resection. In an attempt to improve the outlook for patients with RPS, sarcoma specialists have employed various adjuvant therapies, including extermal beam radiation, intraoperative radiation, brachyradiation and systemic chemotherapy. This article reviews the presentation and prognosis of RPS, and focuses on the results of new treatment strategies compared with conventional management.A Medline search of the English literature was performed to identify all retrospective and prospective reports relating to the management of adult RPS published since 1980. Series that did not analyse RPS separately from other intra-abdominal or extra-abdominal sarcomas or other malignancies were excluded, and information on investigation, presentation, prognostic factors, treatment and outcome was extracted from the remaining reports. Survival and local control data were collected from reports that contained at least 30 cases of RPS (n = 31).While surgical resection remains the cornerstone of treatment for RPS, the majority of patients will relapse and die from sarcoma within 5 years of resection. Adjuvant radiation may improve these results, but further trials are required to definitively demonstrate its benefit. Possible reasons for the failure of conventional treatment are discussed, and alternative strategies designed to overcome these obstacles are presented.

Proliferation parameters in epidermoid carcinomas of the anal canal.

PURPOSE: In a prospective study, we assessed the proliferation parameters in primary epidermoid carcinomas of the anal canal, and results were compared with those in cervical carcinomas. METHODS: Between January 1992 and December 1996, 32 patients with primary epidermoid carcinoma of the anal canal were studied prospectively. Patients were given i.v. bromodeoxyuridine and proliferation parameters were obtained using flow cytometry. The treatment protocol consisted of radiation therapy (XRT) (24 Gy/12-3.5 week split-28 Gy/14) and concurrent 5-fluorouracil and mitomycin C. Proliferation parameters were not obtained in six patients, leaving 26 patients in the analysis. There were 16 females and ten males, with two T1, 16 T2, five T3 and three T4 lesions. Median follow-up was 3.6 years. There were 22 squamous cell and four basaloid carcinomas. Six tumors were aneuploid. RESULTS: Median values for T(s) and S-phase fraction were 7.7 h and 8.2%, respectively. The median LI was 6.8% (0.9-35.7%), and the median T(pot) was 4.1 days (0.9-30 days). There was no correlation of LI or T(pot) with gender, age, tumor stage, size or histology. Local failure was observed in five patients (T(pot)>4.1 days, n=3; LI>6.8%, n=4). Isolated regional failure or distant disease in the absence of local failure was not observed. The small number of outcome events precluded a definitive analysis of the prognostic role of LI and T(pot). Values for the proliferation parameters were similar to those in our updated study of patients with carcinoma of the uterine cervix (n=107), median LI of 6.7% and median T(pot) of 5.5 days. CONCLUSIONS: We conclude that proliferation parameters in anal carcinomas are similar to those in cervical carcinomas. Rapid tumor proliferation does not have an apparent adverse impact on outcome in anal carcinomas managed by split-course XRT with concurrent 5-florouracil and mitomycin C.

Temporal relation between acoustic and force responses at the adductor pollicis during nondepolarizing neuromuscular block.

BACKGROUND: Contracting muscle emits sounds. The purpose of this study was to compare the time course of muscular paralysis at the adductor pollicis muscle (AP) with use of acoustic myography and mechanomyography. METHODS: Thirteen elective surgery patients, American Society of Anesthesiologists physical status I, received rocuronium (0.6 mg/kg intravenously) as a bolus dose during general anesthesia. Force of AP was measured with use of a strain gauge, and sounds were recorded simultaneously with use of a small condenser microphone fixed on the palmar surface of the hand over the AP. Supramaximal stimulation was applied to the ulnar nerve at 0.1 Hz for 45-60 min. In seven patients, the response to train-of-four stimulation was also recorded during recovery. RESULTS: Force and sounds both were equally sensitive in measuring maximum block. The relation between sound and force was curvilinear, with good agreement near 0 and 100% and acoustic response exceeding mechanical response at intermediate levels of block. The acoustic signal had a slower onset and a faster recovery than the force response. The fade response of sound to train-of-four stimulation also recovered faster than that of force. CONCLUSION: Acoustic myography is an alternative method to monitor muscular paralysis that is easy to set up and applicable to most superficial muscles. However, the time course of relaxation at AP using acoustic myography differs from the time course of force relaxation. Therefore, these two methods are not equivalent when applied to AP.

Urinary incontinence.

BACKGROUND: One of the more prevalent conditions associated with aging is urinary incontinence (UI), which may affect up to 55% of women and 34% of men older than 65 years. As a result of increasing longevity in developed nations, the proportion of UI-susceptible individuals continues to grow, presenting clinical and economic challenges to healthcare providers. OBJECTIVE: To assist the clinician in making informed decisions regarding UI, provide information on the wider ramifications of the disease, and provide a comprehensive overview of the condition. DATA SOURCES: MEDLINE (1966-December 1998) was searched for relevant publications using the following search terms: UI, UI in the elderly, treatment of UI, oxybutynin, flavoxate, vasopressin, quality of life in UI, and economic impact of UI. DATA SYNTHESIS: Key articles relating to the etiology, diagnosis, classification, economic burden, quality of life, and treatment of UI were retrieved, and this information formed the basis of the review. CONCLUSIONS: Although UI can be controlled relatively well with existing therapies, only about 50% of affected patients may actually seek care. There are a variety of therapeutic options available for the treatment of UI, although pharmacologic intervention is presently a relatively minor component of overall care; this suggests that effective drug therapy might play a more significant role in the future. The economic burden associated with the care of the incontinent patient is substantial, and in the US the direct medical cost of the disease was estimated at $25.5 billion in 1995. The disease also has a large impact on the individual UI patient, negatively affecting many parameters normally associated with a tolerable health-related quality of life.