Access to Methotrexate Monitoring in Latin America: A Multicountry Survey of Supportive Care Capacity

High-dose methotrexate (HDMTX) is used to treat a broad spectrum of cancers. Methotrexate (MTX) monitoring and adequate supportive care are critical for safe drug administration; however, MTX level timing is not always possible in low- and middle-income countries. The aim of this study was to evaluate HDMTX supportive care capacity and MTX monitoring practices in Latin America (LATAM) to identify gaps and opportunities for improvement. A multicenter survey was conducted among LATAM pediatric oncologists. Twenty healthcare providers from 20 institutions answered the online questionnaire. HDMTX was used to treat acute lymphoblastic leukemia (ALL; 100%), non-Hodgkin lymphoma (84.2%), diffuse large B-cell lymphoma (47.4%), osteosarcoma (78.9%), and medulloblastoma (31.6%). Delays in starting HDMTX infusion were related to bed shortages (47.4%) and MTX shortages (21.1%). MTX monitoring was performed at an in-hospital laboratory in 52%, at an external/nearby laboratory in 31.6%, and was not available in 10.5%. Median interval between sampling and obtaining MTX levels was ≤ 2 h in 45% and ≥ 6 h in 30%, related to laboratory location. Sites without access to MTX monitoring reduced the MTX dose for patients with high-risk ALL or did not include MTX in the treatment of patients with osteosarcoma. Respondents reported that implementation of point-of-care testing of MTX levels is feasible. In LATAM, highly variable supportive care capacity may affect the safe administration of MTX doses. Improving accessibility of MTX monitoring and the speed of obtaining results should be prioritized to allow delivery of full doses of MTX required by the current protocols.

A Systematic Review of High-Dose Methotrexate for Adults with Primary Central Nervous System Lymphoma

Primary central nervous system lymphoma (PCNSL) is a highly aggressive non-Hodgkin lymphoma that is confined within the CNS. Due to its ability to cross the blood-brain barrier, high-dose methotrexate (HDMTX) is the backbone for induction chemotherapy. This systematic review was conducted to observe outcomes among different HDMTX doses (low, <3 g/m²; intermediate, 3-4.9 g/m²; high, ≥5 g/m²) and regimens used in the treatment of PCNSL. A PubMed search resulted in 26 articles reporting clinical trials using HDMTX for PCNSL, from which 35 treatment cohorts were identified for analysis. The median dose of HDMTX used for induction was 3.5 g/m² (interquartile range IQR, 3-3.5); the intermediate dose was most frequently used in the studies examined (24 cohorts, 69%). Five cohorts used HDMTX monotherapy, 19 cohorts used HDMTX + polychemotherapy, and 11 cohorts used HDMTX + rituximab ± polychemotherapy. Pooled overall response rate (ORR) estimates for low, intermediate, and high dose HDMTX cohorts were 71%, 76%, and 76%, respectively. Pooled 2-year progression-free survival (PFS) estimates for low, intermediate, and high HDMTX dose cohorts were 50%, 51%, and 55%, respectively. Regimens that included rituximab showed a tendency to have higher ORR and 2-year PFS than those that did not include rituximab. These findings indicate that current protocols utilizing 3-4 g/m² of HDMTX in combination with rituximab provide therapeutic efficacy in PCNSL.

Impact of COVID-19 in pediatric oncology care in Latin America during the first year of the pandemic

BACKGROUND

The ongoing coronavirus 2019 disease (COVID-19) pandemic strained medical systems worldwide. We report on the impact on pediatric oncology care in Latin American (LATAM) during its first year.

METHOD

Four cross-sectional surveys were electronically distributed among pediatric onco-hematologists in April/June/October 2020, and April/2021 through the Latin American Society of Pediatric Oncology (SLAOP) email list and St Jude Global regional partners.

RESULTS

Four hundred fifty-three pediatric onco-hematologists from 20 countries responded to the first survey, with subsequent surveys response rates above 85%. More than 95% of participants reported that treatment continued without interruption for new and active ongoing patients, though with disruptions in treatment availability. During the first three surveys, respondents reported suspensions of outpatient procedures (54.2%), a decrease in oncologic surgeries (43.6%), radiotherapy (28.4%), stem cell transplants (SCT) (69.3%), and surveillance consultations (81.2%). Logistic regression analysis showed that at the beginning of the first wave, participants from countries with healthcare expenditure below 7% were more likely to report a decrease in outpatient procedures (odds ratio [OR]: 1.84, 95% CI: 1.19-2.8), surgeries (OR: 3, 95% CI: 1.9-4.6) and radiotherapy (OR: 6, 95% CI: 3.5-10.4). Suspension of surveillance consultations was higher in countries with COVID-19 case fatality rates above 2% (OR: 3, 95% CI: 1.4-6.2) and SCT suspensions in countries with COVID-19 incidence rate above 100 cases per 100,000 (OR: 3.48, 95% CI: 1.6-7.45). Paradoxically, at the beginning of the second wave with COVID-19 cases rising exponentially, most participants reported improvements in cancer services availability.

CONCLUSION

Our data show the medium-term collateral effects of the pandemic on pediatric oncology care in LATAM, which might help delineate oncology care delivery amid current and future challenges posed by the pandemic.

Subsequent malignant neoplasms in the pediatric age in retinoblastoma survivors in Argentina

BACKGROUND

Retinoblastoma survivors in low- and middle-income countries are exposed to high-intensity treatments that potentially place them at higher risk of early subsequent malignant neoplasms (SMNs).

METHODS

We followed 714 (403 [56.4%] nonhereditary and 311 [43.5%] hereditary) retinoblastoma survivors diagnosed from August 1987 to December 2016, up to the age of 16 years. We quantified risk of SMNs with cumulative incidence (CI) and standardized incidence ratios (SIR) analysis. Multivariate regression Cox model was used to determine the association of treatments and risk of SMNs.

RESULTS

Median follow-up was of 9 years (range: 0.18-16.9) and 24 survivors (3.36%) developed 25 SMNs (n = 22 hereditary, n = 2 nonhereditary). SMNs included sarcomas (osteosarcomas, Ewing sarcomas, rhabdomyosarcomas; n = 12), leukemias (n = 5), and central nervous system tumors (CNS; n = 3). All cases of acute myeloid leukemia (AML) and most of Ewing sarcomas occurred within 5 years of retinoblastoma diagnosis. The type of SMN was the main indicator of mortality (five of five patients with leukemias, six of 12 with sarcomas, and zero of three with CNS tumors died). Compared to the general population, radiation increased the risk of Ewing sarcoma in hereditary survivors by 700-fold (95% CI = 252-2422.6) and chemotherapy increased the risk of AML by 140-fold (95% CI = 45.3-436). The CI of SMNs for hereditary survivors was 13.7% (95% CI = 8.4-22.1) at 15 years.

CONCLUSION

Retinoblastoma survivors from Argentina are at higher risk of developing SMNs early in life compared to the general Argentinean population, especially those treated with radiation plus chemotherapy. AML and Ewing sarcoma presented within 5 years of retinoblastoma diagnosis are associated with chemotherapy and radiation exposure.

GCT-71. SIOP STRATEGY TREATMENT FOR CENTRAL NERVOUS SYSTEM GERM CELL TUMORS IN A MIDDLE INCOME COUNTRY

BACKGROUND/OBJECTIVES

Central nervous system (CNS) germ cell tumors (GCTs) represent 3% of primary paediatric brain tumours in occident. They can be divided into major groups including germinomas and nongerminomatous GCTs (NGGCTs). The aim is to describe demographic characteristics, Event Free Survival (EFS) and Overall Survival (OS) in patients with GCTs treated at Oncology Unit of Garrahan Hospital (HG).

DESIGN/METHODS

Retrospective analysis of patients with GCTs admitted between September 1st,2000 to September 1st,2019. Variables analysed: age, localization, treatment, relapse and death. Patients were treated per SIOP-CNSGCTs protocol. For statically analysis SPSS (IBM), for EFS/OS Kaplan-Meyer, Long-rank for significance.

RESULTS

Fifty-seven patients were included, comprising 38 Germinomas and 19 NGGCTS. Median age was 146 months (range 11–228). Primary site in localized Germinomas were pineal (16p), suprasellar (7p) and bifocal (7p). Five-year EFS and OS of 100% and 88.5%, respectively. Four patients presented metastatic disease, with an EFS and OS of 60.9% and 66.6%. Tumor site in localized NGGCT were pineal(8p) and suprasellar(5p). Five-year EFS was 81.8% and OS was 80.2%. No patients presented metastatic disease. All patients with high-risk tumor markers at diagnosis relapsed. No significative differences were found in OS neither EFS between groups (Germinomas OS5y 90% vs NGGCTs 74.6%p=0.19[CI95%0.0786–1.689]), (Germinomas EFS5y 78.9% vs NGGCTs5y 81.8%p=0.85[CI95%0.3046–4.230). Global OS and EFS5y was 83% and 72.9%.

CONCLUSION

OS of our cohort is lower than what has been shown in current literature. This result may be related to the lack of resources and lower social economic status in our population.

Urinary symptoms and infections among female garment factory workers in Bangladesh

BACKGROUND

The prevalence of urinary symptoms and infections among female garment factory workers in Bangladesh - a large developing country - is largely unknown. Garment sector is this country's main economic growth engine.

OBJECTIVES

This paper focuses on garment industry workers and compares the findings with another group of low socioeconomic status working women.

METHODS

Urinary tract symptoms (UTS) were determined by self-reported survey including International Consultation on Incontinence Modular Questionnaire-Female Lower Urinary Tract Symptoms (ICIQ-FLUTS) and urinary tract infection (UTI) was determined among a subset population by urine dipstick tests.

RESULTS

Data were collected from 310 garment workers and 297 comparison workers. About one third of garment workers (31.94%) and comparison workers (29.97%) could take up to 3 toilet breaks in a day. Garment workers reported to be more sexually active and menstruation was more common among them compared to comparison workers. They reported a significantly higher prevalence of malodorous urine and vaginal discharge. Garment workers were found to have a significantly higher ICIQ-FLUTS score of voiding than comparison workers (0.44 vs. 0.27; p-value = 0.0167).Among the study respondents, 148 garment workers and 134 other workers provided urine samples and 21 (7.45%) were found to have UTI. After considering all the risk factors in multivariate model, garment work had a significant impact on the probability of having UTI with Odds Ratio of 5.46 (p-value = 0.0374; 95% CI = 1.10, 26.97) compared to other workers.

CONCLUSIONS

This study highlights the prevalence and burden of urinary symptoms and infections among female worker populations in Bangladesh.

A portable miniaturized laser heterodyne radiometer (mini‑LHR) for remote measurements of column CH4 and CO2

We present the design of a portable version of our miniaturized laser heterodyne radiometer (mini-LHR) that simultaneously measures methane (CH4) and carbon dioxide (CO2) in the atmospheric column. The mini-LHR fits on a backpack frame, operates autonomously, and requires no infrastructure because it is powered by batteries charged by a folding 30 W solar panel. Similar to our earlier instruments, the mini-LHR is a passive laser heterodyne radiometer that operates by collecting sunlight that has undergone absorption by CH4 and CO2. Within the mini-LHR, sunlight is mixed with light from a distributive feedback (DFB) laser centered at approximately 1.64 μm where both gases have absorption features. The laser scans across these absorption features roughly every minute and the resulting beat signal is collected in the radio frequency (RF). Scans are averaged into half hour and hour data products and analyzed using the Planetary Spectrum Generator (PSG) retrieval to extract column mole fractions. Instrument performance is demonstrated through two deployments at significantly different sites in interior Alaska and Hawaii. The resolving power (λ/∆λ) is greater than 500,000 at 1.64 μm with precisions of better than 20 ppb and 1 ppm for CH4 and CO2, respectively. Because mini-LHR instruments are portable and can be co-located, they can be used to characterize bias between larger, stationary, column observing instruments. In addition, mini-LHRs can be deployed quickly to respond to transient events such as methane leaks or can be used for field studies targeting geographical regions.

Impact of vaccination on antibiotic usage: a systematic review and meta-analysis

BACKGROUND

Vaccines may reduce antibiotic use and the development of resistance.

OBJECTIVES

To provide a comprehensive, up-to-date assessment of the evidence base relating to the effect of vaccines on antibiotic use.

DATA SOURCES

Ovid MEDLINE, Embase, the Cochrane Library, ClinicalTrials.gov and WHO Trials Registry.

STUDY ELIGIBILITY CRITERIA

Randomized controlled trials (RCTs) and observational studies published from January 1998 to March 2018.

PARTICIPANTS

Any population.

INTERVENTIONS

Vaccines versus placebo, no vaccine or another vaccine.

METHODS

Titles, abstracts and full-texts were screened independently by two reviewers. Certainty of RCT evidence was assessed using GRADE.

RESULTS

In all, 4980 records identified; 895 full-text reports assessed; 96 studies included (24 RCTs, 72 observational). There was high-certainty evidence that influenza vaccine reduces days of antibiotic use among healthy adults (one RCT; n = 4253; rate reduction 28·1%; 95% CI 16·0-38·4); moderate-certainty evidence that influenza vaccines probably reduce antibiotic use in children aged 6 months to 14 years (three RCTs; n = 610; ratio of means 0·62; 95% CI 0·54-0·70) and probably reduce community antibiotic use in children aged 3-15 years (one RCT; n = 10 985 person-seasons; risk ratio 0·69, 95% CI 0·58-0·83); and moderate-certainty evidence that pneumococcal vaccination probably reduces antibiotic use in children aged 6 weeks to 6 years (two RCTs; n = 47 945; rate ratio 0·93, 95% CI 0·87-0·99) and reduces illness episodes requiring antibiotics in children aged 12-35 months (one RCT; n = 264; rate ratio 0·85, 95% CI 0·75-0·97). Other RCT evidence was of low or very low certainty, and observational evidence was affected by confounding.

CONCLUSIONS

The evidence base is poor. Although some vaccines may reduce antibiotic use, collection of high-quality data in future vaccine trials is needed to improve the evidence base.

PROSPERO REGISTRATION

CRD42018103881.

Nutritional status at diagnosis of cancer in children and adolescents in Guatemala and its relationship to socioeconomic disadvantage: A retrospective cohort study

BACKGROUND

At least 80% of children with cancer live in low- and middle-income countries where the prevalence of malnutrition and socioeconomic disadvantage is high. We examined the relationship between nutritional status (NS), assessed by arm anthropometry, and socioeconomic status (SES) in children diagnosed with cancer at Unidad Nacional de Oncologia Pediatrica (UNOP) in Guatemala over a three-year period.

METHOD

Patients aged 0 to 18 years of age diagnosed between January 2015 and December 2017 were included. NS was evaluated by mid-upper arm circumference, triceps skin fold thickness, and serum albumin level, and subjects were classified as adequately nourished, moderately depleted, and severely depleted nutritionally. SES was measured by a 15-item instrument developed at UNOP.

RESULTS

Of 1365 patients diagnosed in the study period, 1060 (78%) fulfilled the eligibility criteria. Only 6% of patients were classified as medium to high, the remainder as medium-low to extremely low SES. Almost 47% were severely depleted at diagnosis, 19% moderately depleted, and 34% adequately nourished. SES was shown to be a determinant of NS; with progressively lower SES, the probability of a decline in NS increased by a factor of 1.04 points (P < 0.0001). Leukemia and lymphoma were also important predictors of nutritional depletion with odds ratios of 6.08 (95% CI, 1.74-28.28; P = 0.008) for leukemias and 4.83 (95% CI, 1.33-23.03; P = 0.03) for lymphomas.

CONCLUSION

Both low SES and a diagnosis of leukemia or lymphoma are strong predictors of poor NS at diagnosis in children with cancer in Guatemala.

Prevalence and risk factors of depression among garment workers in Bangladesh

BACKGROUND

Depression is a growing health issue in both developed and developing countries. General unawareness at the population level, lack of training among health care providers and scarcity of resources including treatment opportunities may conceal the real burden of depression in developing countries, and more epidemiological studies on its prevalence and risk factors are critically needed.

AIM

This study reports the prevalence of depression and its associated risk factors among female garment factory workers in Bangladesh - a major supplier country of clothes for the Western market. This research should generate useful evidence for national and international stakeholders who have an interest in improving health, safety and well-being of outsourced factory workers.

METHODS

A survey was conducted on a sample of 600 lower socio-economic status working women including garment workers. This survey collected data on demographic and health profile of these workers. The primary outcome was depression as measured by Patient Health Questionnaire 9. It also obtained data on traumatic life events and post-traumatic stress disorder.

RESULTS

The prevalence of depression was 23.5%: 20.9% among garment workers and 26.4% among others. Part-time employment (odds ratio-OR): 2.36, 95% confidence interval (95% CI): 1.01-5.51), chronic pain (OR: 1.67, 95% CI: 1.01-2.78), two or more traumatic life events (OR: 6.43, 95% CI: 2.85-14.55) and dysuria (OR: 2.50, 95% CI: 1.02-6.15) were found to be significantly associated with depression among these workers in multivariate regression model. Depression prevalene lowered by 11% among these workers for every additional monthly earning of 1,000 taka (US$12).

CONCLUSION

Depression is a multifaceted health issue with many personal, social, economic and health determinants and consequences. This study demonstrates that the prevalence of moderate-to-severe depression among working women in Bangladesh is quite high. Prevention and treatment of depression in developing countries and societies can reduce suffering, lower incidence of suicide, and prevent economic loss. Creating awareness on outsourced workers' poor mental health may help in developing initiatives to protect and preserve their well-being.

Intravenous Immunoglobulin in the Treatment of Hematologic Disorders in Pediatrics

Intravenous immunoglobulin (IVIG) is pooled immunoglobulin G derived from human blood donors. It was introduced in the early 1980s to treat immunodeficiency disorders. Since then, its use has expanded to other fields such as neurology, rheumatology, and hematology. IVIG has been used to provide passive immunity in qualitative and quantitative immunoglobulin disorders, to neutralize antibodies in immune-mediated diseases, and as an immune modulatory agent. The difficulty of producing IVIG in high quantities, in addition to a growing list of "off-label" indications, has resulted in a worldwide shortage and increase in cost. From a pediatric hematology perspective, IVIG is considered an appropriate therapeutic option in autoimmune cytopenias, sometimes coadministrated with steroids. Its use in other hematologic disorders is questionable, and there is not sufficient evidence to recommend it. This article provides clear information to the general pediatrician about indications for IVIG therapy in children with hematologic disorders. [Pediatr Ann. 2017;46(1):e13-e18.].

Comparing determinants of physical activity in Puerto Rican, Mexican-American, and non-Hispanic white breast cancer survivors

Purpose

Physical activity (PA) has a myriad of benefits for breast cancer survivors, including a reduced risk of cancer recurrence. Latinas are less physically active than are women in the general population and little is known about Latina breast cancer survivors’ levels of PA or their beliefs related to PA. We conducted a survey of 50 Puerto Rican (PR), 50 Mexican-American (MA) and 50 non-Hispanic white (NHW) breast cancer survivors to investigate similarities and differences in PA and social cognitive theory (SCT) constructs associated with PA.

Methods

We collected information on current PA using the Godin Leisure Time Exercise Questionnaire (GLTEQ); comorbidities; anthropometric measures of body mass index [BMI (kg/m²)] and waist-to-hip (W:H) ratio; and SCT measures, including exercise self-efficacy, exercise barriers self-efficacy, modeling and social support from friends and family. Descriptive statistics, one-way analysis of variance of differences between groups and regression models of the predictors of PA were performed.

Results

Survivors from the three groups were similar in age (M = 56.8, SD = 11.0), BMI (M = 29.0, SD = 5.7) and co-morbidity (M = 2.09, SD = 1.69). Survivors differed in PA (p < 0.001), self-efficacy (p = 0.05), modeling (p = 0.03) and social support from family (p = 0.05). Social support from family member and exercise barriers self-efficacy were predictors of PA.

Conclusions

Consistent with published studies, Hispanic breast cancer survivors self-report that they are less physically active than are non-Hispanic whites. SCT variables associated with PA differ among Hispanic subgroups and non-Hispanic whites. Further research is warranted in order to understand determinants of physical activity for specific ethnic breast cancer survivors.

The prevalence and risk factors of Post-Traumatic Stress Disorder among workers injured in Rana Plaza building collapse in Bangladesh

OBJECTIVES

Prevalence and risk factors of PTSD among injured garment workers who survived a major factory collapse.

METHODS

Survivors receiving treatment or rehabilitation care at one year post event were surveyed, which included Post Traumatic Stress Disorder Checklist Specific version.

RESULTS

The respondents consisted of 181 people with a mean age of 27.8 years and a majority had less than high school education (91.2%). Multivariable logistic regression found that the odds of having PTSD was higher among married (OR: 3.2 [95% CI: 1.3-8.0]), those who used to work more than 70 hr/week (OR: 2.4 [1.1-5.3]), workers who used to hold higher job positions (OR: 2.6 [1.2-5.6]) or who had a concussion injury (OR: 3.7 [1.4-9.8]). Among the respondents, 83.4% remained unemployed, and only 57.3% (63 people) reported receiving a quarter or less of what they were promised as compensation.

CONCLUSIONS

Probable PTSD was prevalent among surviving workers of the Rana Plaza building collapse in Bangladesh.

Abstract B57: Comparing determinants of physical activity in Puerto Rican, Mexican-American, and non-Hispanic white breast cancer survivors

Purpose: Among the plethora of benefits of moderate to vigorous levels of physical activity for breast cancer survivors is a link to reduced risk for cancer recurrence. However, after the experience of cancer, many breast cancer survivors who were not previously active will stay inactive; and, those who were active do not return to their previous level of activity. Latinas are among the least physically active segments of the U.S. population. Utilizing a Social Cognitive Theory (SCT) based model as a guide, we conducted a cross sectional survey to investigate similarities and differences in SCT variables associated with current level of physical activity in Puerto Rican, Mexican-American and non-Hispanic white breast cancer survivors. The results reported here are being used to culturally adapt an exercise intervention specific for Mexican-American and Puerto Rican breast cancer survivors.

Methods: A total of 150 breast cancer survivors completed an interviewer-guided survey. Fifty Puerto-Rican (PR) participants completed the survey in San Juan Puerto Rico in the Oncologic Hospital. Fifty Mexican-American (MA) and fifty non-Hispanic (NHW) white breast cancer survivors completed the survey in the Breast Clinic at the University of Texas M. D. Anderson Cancer Center. The survey included information on: current physical activity (Godin Leisure Time Exercise Scale, [GLTES]); current health status; and, anthropometric measures of BMI (kg/m2) with hip and waist circumferences (W:H). SCT measures included: exercise self-efficacy (ESE), barriers self-efficacy (BSE), modeling (MOD), social support from friends (SSFR), and social support from family (SSFA). Descriptive statistics, one-way analysis of variance and correlation analyses were conducted for the three groups.

Results: Participants were similar in age (M=56.75, SD=11.0), BMI (M=29.0, SD=5.7) and level of co-morbidity (M=1.63, SD=1.42). There were differences in GLTES score (p&lt;.001) with the PR group having the lowest level (M=14.0, SD=19.1), MA lower level (M=33.5, SD=18.8) and NHW highest levels (M=43.7, SD=27.6) of activity. SCT variables that differed between groups were ESE (p=.05), MOD (p=.034) and SSAF (p=.052). SCT variables associated with current physical activity differed between the three groups: for NHW BSE (r=.58, p&lt;.001) and SSFA (r=.26, p=.01); for PR ESE (r=.58, p&lt;.001), BSE (r=.58, p&lt;.001); and, for MA MOD (r=.41, p=.003) were associated with current physical activity.

Conclusions: Consistent with current literature, Hispanic breast cancer survivors indicate that they are less physically active than non-Hispanic whites. Variables associated with current physical activity differ between Hispanic breast cancer survivor groups and non-Hispanic whites. Further research to understand culturally specific variables of exercise behaviors for ethnic breast cancer survivors are warranted in order to develop culturally competent interventions that can result in increased physical activity.

Citation Information: Cancer Epidemiol Biomarkers Prev 2011;20(10 Suppl):B57.

Metallic nanowires by full wafer stencil lithography

Aluminum and gold nanowires were fabricated using 100 mm stencil wafers containing nanoslits fabricated with a focused ion beam. The stencils were aligned and the nanowires deposited on a substrate with predefined electrical pads. The morphology and resistivity of the wires were studied. Nanowires down to 70 nm wide and 5 mum long have been achieved showing a resistivity of 10 microOmegacm for Al and 5 microOmegacm for Au and maximum current density of approximately 10(8) A/cm(2). This proves the capability of stencil lithography for the fabrication of metallic nanowires on a full wafer scale.

3-D modulable PDMS-based microlens system

The design, simulation, fabrication and characterization of 3-D modulable micro-optical system based on poly-dimethilsiloxane (PDMS) are presented in this paper. This system consists on two uncoupled PDMS lenses with different diameter (2 and 10 microm). Under stretching conditions, the dimensions of the small lens are not modified, whereas the geometry of the bigger lens is shifted from spherical to elliptical. A combination of different technologies is used to fabricate this microsystem: silicon, polymer and soft-lithography microfabrication techniques. This combination allows obtaining structures with a simple and mass production technology. Experimental results confirm the predicted numerical simulations, showing that, when the structure is under stretching conditions, the first focus is virtually invariable whereas the second focus becomes a Sturm zone.

A single nanotrench in a palladium microwire for hydrogen detection

The hydrogen sensing characteristics of a single nanotrench fabricated by focused ion beam milling (FIB) in an evaporated palladium microwire are presented. In situ atomic force microscopy (AFM) measurements proved that, in the presence of H(2), the trench closes and electrically connects the initially separated parts of the wire due to the increase in volume of the material. Therewith, an electrical current can be switched through the wire. With experiments under various H(2) concentrations and a mathematical model, we describe the closing mechanism of the trench with respect to various parameters, including the substrate material, film thickness, trench size and wire dimensions. Results have been compared with those from equivalent continuous wires. Thin SiO(2) and polyimide (PI) layers on silicon were used to study the effect of substrate elasticity. Sufficient lateral expansion of Pd to close trenches of up to 70 nm in width has only been observed on PI, which we attribute to its advantageous elastic properties. The scale of the response times allowed the observation of two superposing effects: the chemical conversion of Pd to PdH(x) and the mechanical closing of the trench.

The utility of an automated electronic system to monitor and audit transfusion practice

BACKGROUND AND OBJECTIVES

Transfusion laboratories with transfusion committees have a responsibility to monitor transfusion practice and generate improvements in clinical decision-making and red cell usage. However, this can be problematic and expensive because data cannot be readily extracted from most laboratory information systems. To overcome this problem, we developed and introduced a system to electronically extract and collate extensive amounts of data from two laboratory information systems and to link it with ICD10 clinical codes in a new database using standard information technology.

MATERIALS AND METHODS

Three data files were generated from two laboratory information systems, ULTRA (version 3.2) and TM, using standard information technology scripts. These were patient pre- and post-transfusion haemoglobin, blood group and antibody screen, and cross match and transfusion data. These data together with ICD10 codes for surgical cases were imported into an MS ACCESS database and linked by means of a unique laboratory number. Queries were then run to extract the relevant information and processed in Microsoft Excel for graphical presentation. We assessed the utility of this data extraction system to audit transfusion practice in a 600-bed adult tertiary hospital over an 18-month period.

RESULTS

A total of 52 MB of data were extracted from the two laboratory information systems for the 18-month period and together with 2.0 MB theatre ICD10 data enabled case-specific transfusion information to be generated. The audit evaluated 15,992 blood group and antibody screens, 25,344 cross-matched red cell units and 15,455 transfused red cell units. Data evaluated included cross-matched to transfusion ratios and pre- and post-transfusion haemoglobin levels for a range of clinical diagnoses. Data showed significant differences between clinical units and by ICD10 code.

CONCLUSION

This method to electronically extract large amounts of data and linkage with clinical databases has provided a powerful and sustainable tool for monitoring transfusion practice. It has been successfully used to identify areas requiring education, training and clinical guidance and allows for comparison with national haemoglobin-based transfusion guidelines.

Deep Impact: observations from a worldwide Earth-based campaign

On 4 July 2005, many observatories around the world and in space observed the collision of Deep Impact with comet 9P/Tempel 1 or its aftermath. This was an unprecedented coordinated observational campaign. These data show that (i) there was new material after impact that was compositionally different from that seen before impact; (ii) the ratio of dust mass to gas mass in the ejecta was much larger than before impact; (iii) the new activity did not last more than a few days, and by 9 July the comet's behavior was indistinguishable from its pre-impact behavior; and (iv) there were interesting transient phenomena that may be correlated with cratering physics.

Efficacy of preoperative versus postoperative ketorolac tromethamine 0.5% in reducing inflammation after cataract surgery

PURPOSE

To compare the efficacy of 30 minute preoperative versus 1 day postoperative administration of ketorolac tromethamine 0.5% ophthalmic solution (Acular) in reducing anterior chamber inflammation after cataract surgery.

SETTING

The Hermann Eye Center, The University of Texas Health Science Center-Houston, Texas, USA.

METHODS

Fifty eyes of 48 consecutive patients scheduled for phacoemulsification with intraocular lens implantation were included. Before surgery, patients were randomly assigned to start the study drug 30 minutes preoperatively or 1 day postoperatively. No other antiinflammatory agents were used intraoperatively or postoperatively. Main outcome measures were flare and cell counts.

RESULTS

Preoperative and postoperative flare and cell counts did not differ significantly between the 2 treatment groups at any time. Both groups showed significant increases in flare (P =.0001) and cells (P =.0001) 1 day postoperatively. Flare and cells returned to baseline levels by day 28 in both groups. There was no significant difference at any time between the 2 groups in the change from the preoperative level of inflammation.

CONCLUSIONS

There was no difference between administering ketorolac 30 minutes preoperatively versus 1 day postoperatively in reducing inflammation.

Low-dose postoperative transconjunctival application of mitomycin C in rabbit trabeculectomy

PURPOSE

Mitomycin C (MMC) is commonly administered during filtering surgery to enhance the success of the procedure. Unfortunately, the increased success rate is associated with complications, including late bleb leaks, endophthalmitis, and ciliary epithelial toxicity. The purpose of this study was to investigate a safe and effective dose regimen for MMC to reduce incidence of those complications.

METHODS

Trabeculectomy was performed in 36 rabbits. MMC was applied only during surgery, only one day after surgery, or once daily after surgery for 3 days at lower concentrations. Balanced salt solution (BSS) was administered during surgery to one group as a placebo. The time to bleb failure was determined and the eyes were evaluated histopathologically. Success and toxicity were compared for the different treatment groups.

RESULTS

The mean time until trabeculectomy failure was 2.83 days for the placebo group, 6.33 days with administration of MMC 0.5 mg/mL during surgery, 7.83 days with administration of MMC 0.5 mg/mL once after surgery, and 11, 9, and 4.83 days with administration of MMC 0.1 mg/mL, 0.05 mg/mL, or 0.025 mg/mL, respectively, once a day for 3 consecutive days. On electron microscopic examination of the ciliary epithelium, toxic effects were greatest with MMC concentrations of 0.5 mg/mL and were less with lower concentrations.

CONCLUSION

The effect of MMC on trabeculectomy survival was dependent on both the concentration and the method of administration. Lower concentrations with multiple postoperative administrations were as effective as but caused less ciliary body toxicity than intraoperative administration of higher concentrations.

Ondansetron/promethazine combination or promethazine alone reduces nausea and vomiting after middle ear surgery

STUDY OBJECTIVES

To determine the incidence of postoperative nausea and vomiting when a combination of ondansetron and promethazine is given prophylactically, and to ascertain the effect of postoperative nausea and vomiting on recovery room duration and patient satisfaction.

DESIGN

Prospective, randomized, placebo-controlled, double-blind study.

SETTING

University-affiliated tertiary-care hospital.

PATIENTS

87 ASA physical status I and II adult patients scheduled for middle ear surgery.

INTERVENTIONS

Patients were randomly assigned to receive one of the following interventions intravenously: ondansetron 4 mg (Group 1), promethazine 25 mg (Group 2), ondansetron 2 mg plus promethazine 12.5 mg (Group 3, combination), or placebo (Group 4).

MEASUREMENTS AND MAIN RESULTS

Independent, study blinded observers recorded complaints of nausea and number of episodes of vomiting for 24 hours following the patient's first response to commands. All patients were contacted the day after discharge to inquire about nausea and vomiting. The awakening time, postanesthesia care unit and day surgery unit durations, opioid use, and side effects were recorded. At the end of the 24-hour period, the study blinded observers asked patients for an overall assessment of their global anesthesia experience using an 11-point scale. During the 24-hour period, the incidence of postoperative nausea and vomiting was reduced from 74% (placebo) to 39% (promethazine; p = 0.03) and 29% (combination; p = 0.003). Compared with placebo, the severity of vomiting was significantly less in the combination group (p = 0.04). The number of very satisfied patients correlated negatively with the incidence of postoperative nausea and vomiting (p < 0.0001) and with the severity of vomiting (p = 0.003).

CONCLUSION

The prophylactic use of an antiemetic with middle ear surgery may reduce postoperative nausea and vomiting over 24 hours, and the ondansetron/promethazine combination or promethazine alone are cost-effective choices. Finally, the combination reduced significantly the severity of vomiting.

N400 and lexical decisions: automatic or controlled processing?

OBJECTIVE

To investigate whether the N400 effect is sensitive to automatic or controlled processes.

METHODS

Two experiments were performed. In one experiment, directly related word pairs were used. In the other experiment, mediated-related word pairs were used. In order to reduce controlled processes, each experiment consisted of 3 tasks: Low- and high-proportion of related pairs, and single presentation lexical decision task.

RESULTS

In the first experiment, the amount of priming was equivalent for the 3 tasks. The N400 effect appeared in the high and low proportion of directly related words, but not in the single presentation task. In the second experiment, behavioral priming was also found in the 3 tasks. However, the N400 effect was observed only in the task with low proportion of related pairs.

CONCLUSION

These results suggest that the N400 effect may be related to controlled processes.

Consensual inflammation following ocular surgery

PURPOSE

To determine whether a consensual inflammatory response occurs following unilateral phacoemulsification or trabeculectomy in humans.

METHODS

Sixty patients undergoing phacoemulsification or primary trabeculectomy were included in the study. Some patients were randomly assigned to have a shield placed on the non-operated eye during surgery. The Kowa laser flare meter (FM-500) and laser cell counter (LC-500) (Kowa Electronics and Optics, Tokyo, Japan) were used to assess the inflammatory response in both eyes. Measurements were taken preoperatively and on postoperative days 1, 7 and 28. The regression analysis with random model effect was used to identify factors which may affect the change of flare and cells in the non-operated eye after surgery. Correlation was evaluated between the inflammatory responses of the paired eyes. A P<0.05 was considered statistically significant for all analyses.

RESULTS

The flare and cells in the non-operated eye showed a small, but significant, increase on day 1 (mean flare increased 2.68 photons/ms from preoperative level with P<0.001 and mean cells increased 2.49 cells/0.5 mm3 from preoperative level with P<0.0001). At day 7 the amount of inflammation was still elevated (mean flare increased 0.41 photons/ms from preoperative level with P<0.001 and mean cells increased 0.63 cells/0.5 mm3 from preoperative level with P<0.001). By day 28, the amount of inflammation in the nonoperated eyes returned to preoperative levels.

CONCLUSIONS

Subclinical inflammation occurs in the non-operated eye following phacoemulsification and trabeculectomy. The etiology of this finding has yet to be elucidated.

A randomized double-masked trial comparing ketorolac tromethamine 0.5%, diclofenac sodium 0.1%, and prednisolone acetate 1% in reducing post-phacoemulsification flare and cells

BACKGROUND AND OBJECTIVE

To compare the efficacy of ketorolac tromethamine 0.5%, diclofenac sodium 0.1%, and prednisolone acetate 1% in reducing flare and cells following cataract surgery.

PATIENTS AND METHODS

Fifty-eight patients undergoing phacoemulsification with posterior chamber intraocular lens implantation were randomly selected to receive either ketorolac tromethamine 0.5%, diclofenac sodium 0.1%, or prednisolone acetate 1% following surgery. The treatment regimen was 1 drop 4 times a day for 1 week, then twice a day for the next 3 weeks. Flare, cells, and intraocular pressures (IOPs) were measured preoperatively and on postoperative days 1, 7, and 28.

RESULTS

No statistically significant differences in either actual flare or cell counts or in change in flare or cell counts from baseline were detected among the three groups. No statistically significant differences in IOP or in change of IOP from preoperative measurements were detected. No medication-related complications were noted at any time.

CONCLUSION

Ketorolac tromethamine 0.5% and diclofenac sodium 0.1% may be as effective and as safe as prednisolone acetate 1% in controlling inflammation following cataract extraction.

Reproducibility of the laser flare meter and laser cell counter in assessing anterior chamber inflammation following cataract surgery

BACKGROUND AND OBJECTIVES

To determine the interobserver and intraobserver reproducibility of the laser flare meter and laser cell counter in assessing anterior chamber inflammation following cataract surgery.

PATIENTS AND METHODS

Thirty-nine eyes with varied degrees of inflammation and 9 normal eyes were included in the study. Anterior chamber flare and cells were evaluated with the slit lamp and graded on a scale of 0 to 4+. The flare and cells were then measured three times each using the flare meter and cell counter by two different, experienced observers. The intraobserver reproducibilities were computed to evaluate repeatability of the instruments operated by the same observer. The first measurement taken by each observer was used to assess reproducibility between the two observers.

RESULTS

The intraobserver reproducibility for overall flare was 0.995 for both observers. The intraobserver reproducibility for overall cells was 0.996 for observer 1 and 0.991 for observer 2. The overall interobserver reproducibility was 0.994 for flare and 0.988 for cells. The correlation between measurements and slit-lamp ratings was 0.78 for flare and 0.56 for cells.

CONCLUSIONS

The intraobserver and interobserver reproducibilities were excellent, with good correlation to slit-lamp measurements. Reproducible results can be obtained using the laser flare meter and the laser cell counter. It is not known whether these results are applicable to other inflammatory processes with higher grades of flare and cells and with different protein and cell types.

Valve membrane adhesion as a cause of Ahmed glaucoma valve failure

PURPOSE

The purpose of this study was to describe a possible mechanism of failure of the Ahmed glaucoma valve (AGV; New World Medical, Rancho Cucamonga, CA).

METHOD

Two AGVS that failed to control intraocular pressure (IOP) were examined. In vivo examination consisted of unroofing the capsule surrounding the implant and injecting fluorescein-stained balanced salt solution into the tube. In one case the entire implant was removed and examined in vitro, and in the other case only the valve portion was removed.

RESULT

No flow in either case extended beyond the valve. In both cases, the membrane valve system was found to be fused and could not be pulled apart.

CONCLUSION

Failure of the AGV may occur due to adhesion of the valve membranes.

[Clinical and etiologic study of 90 cases of chronic diarrhea]

90 patients with chronic diarrhoea underwent this prospective study. They were seen in a private hospital of Lima during 1990 and 1991. According to a methodologic plan for determining sources and the diseases that originate chronic diarrhoea. In all patients hematologic, bioquimic, coprocultures, coproparasitologic exams were done, chest and intestinal transit X-rays. All underwent duodenal content culture. Colon X-ray in 25 cases; proctosigmoidoscopy in 14 and upper digestive endoscopy in 19 patients. Abdominal echography in 12 and TAC in 2 cases. The final results showed as determinant diseases for chronic diarrhoea, according to their frequency: enteroparasitosis (23.3%), functional digestive disorders (20.0%), intestinal bacterial overpopulation (15.5%) of unknown origin (8.8%), colon diverticulus (7.7%) proven and probably (5.5%), lactose intolerance (3.3%), diabetes mellitus (2.2%), and in one case (1.1%) the following: intestinal linfoma, pancreas malignancy, AIDS, colonic and deformation and megaloblastic anemia. The causes of chronic diarrhoea are several and multifactorals and in this study we prove the preeminence of the intestinal parasitosis, functional disorders and intestinal bacterial overpopulation and with less frequency other pathologies.

[Phagocytic capacity of peritoneal exudate cells from rats immunized with a ribosomal preparation of Ty2 Salmonella typhi]

It was compared the activity of exudate peritoneal cells (EPC) obtained from CFW mice immunized either with Salmonella typhi Ty2 ribosomal fraction or whole-cell heat inactivated vaccine, both in comparison with EPC from sham-immunized. In the group which received ribosomal preparation, a subcutaneous dose equivalent to 100 micrograms of RNA in incomplete Freund's adjuvant (IFA) was initially used and 14 days after a booster of the same dose in IFA was given. A single dose of whole-cell heat inactivated vaccine, with 10(6) bacteria in IFA was employed subcutaneously in animals of the second group. EPC from controls and immunized mice were withdrawn at periods of 7, 11, 14, 18, 22, 25, 29 and 31 days after immunization and each sample was incubated in vitro in presence of live virulent non-opsonized S. typhi Ty2 in 1:200 cell-bacteria relation. Twenty four hours after cultivation, EPC bacterial capacity was determined after cell disruption and enumeration of survival bacteria were made through viable counts. Results have shown that EPC from mice immunized were more efficient in eliminating intracellular bacteria than those which came from sham-immunized animals. Also, it was found that EPC from mice immunized with ribosomal preparation were more efficient (maximum P = 0.005) than EPC from the mice which received killed whole bacteria.

On the origin of the positive band in the far-ultraviolet circular dichroic spectrum of fibronectin

The genesis of the positive bands in the far-ultraviolet circular dichroic spectra of human plasma fibronectin and its 31-kDa NH2-terminal heparin-binding fragment was studied. Spectra of ester derivatives of tyrosine, tryptophan, and phenylalanine and of model mixtures of these derivatives in which they are present in the same ratios as in the proteins indicate that all the aromatic side chains make substantial contributions to composite positive bands with maxima several nanometers below those of the proteins. In the presence of solvent perturbants such as polyethylene glycol and ethylene glycol, the bands of the model mixtures are red-shifted to the approximate positions they have in the spectra of the proteins. No additional red shift is seen with solvent perturbation of the proteins, suggesting that the conditions leading to this effect are satisfied within the proteins. A separate effect of solvent perturbation, an increase in amplitude of the positive band, occurs equally in solutions of free aromatic amino acid derivatives and in the proteins. This effect is used to estimate the relative accessibility of the chromophores of fibronectin and its fragment to different perturbants. The possible influence of protein secondary structure on the amplitude of the positive circular dichroic band is discussed.

Structural changes in the NH2-terminal domain of fibronectin upon interaction with heparin. Relationship to matrix-driven translocation

The effects of heparin and various related polysaccharides on the circular dichroic spectra of fibronectin and its 31-kDa NH2-terminal tryptic fragment were studied. These effects were evaluated with respect to (i) spectral features of the native proteins that are sensitive to pH denaturation and breaking of disulfide bonds, (ii) sensitivity of spectral changes to Ca2+, and (iii) the fibronectin-dependent interfacial interaction known as "matrix-driven translocation." We found that native heparin causes an attenuation of the positive CD peak at 228 nm with both the intact protein and the fragment, and causes a small but reproducible red shift in the spectrum of the fragment. All of these changes are analogous to spectral changes seen with denaturation or reduction of the proteins. In contrast to the situation with the intact protein, the heparin-induced spectral changes in the fragment were abolished in the presence of 10 mM Ca2+. Desulfation of heparin lessened or destroyed its ability to induce these changes, and carboxymethylated heparin and dextran sulfate induced different kinds of spectral alterations. Fibronectin and heparin determinants required for the induction of the characteristic spectral shift of the NH2-terminal domain corresponded to those required for matrix-driven translocation, suggesting that the associated conformational change in fibronectin plays a role in this biophysical effect.

Conformational changes accompanying the binding of antithrombin III to thrombin

The conformational aspects of the binding of antithrombin III to thrombin were investigated by difference spectroscopy, circular dichroism, and optical rotatory dispersion. The CD and ORD studies indicate an increase of 6--8% in alpha-helix content at the expense of the beta structure, while the results from difference spectroscopy showed an increased exposure of approximately seven tyrosine residues. In the presence of heparin there is a slightly greater increase in helicity which is accompanied by exposure of an average of two tryptophan and one tyrosine residues. These spectral results indicate that the thrombin-antithrombin III complex formed in the presence of heparin differs in its conformation from that produced in its absence.