Evaluating the Frequencies of CNOT3, GRIA1, NFATC2, and PNPLA3 Variant Alleles and Their Association with L-Asparaginase Hypersensitivity in Pediatric Acute Lymphoblastic Leukemia in Addis Ababa, Ethiopia

Introduction

L-asparaginase is a vital component for the treatment of childhood acute lymphoblastic leukemia (ALL); however, hypersensitivity reactions and hepatotoxicity hinder its anti-neoplastic efficacy. Previous reports indicated that genetic variants in CNOT3, GRIA1, and NFATC2 genes might be associated with hypersensitivity reactions and PNPLA3 with liver function.

Objective

In this study, it was investigated whether this association also exists in a pediatric ALL cohort from Ethiopia.

Methods

Three variants GRIA1 rs4958351, CNOT3 rs73062673, and NFATC2 rs6021191 were genotyped in a cohort of 160 patients. Association analysis to investigate the association with hypersensitivity reactions was performed using logistic regression analyses. Besides these variants, a variant in PNPLA3 (rs738409) was genotyped to assess the association with liver function.

Results

Genotype frequencies of GRIA1 rs4958351, CNOT3 rs73062673, and NFATC2 rs6021191 were higher/lower than previously reported. One hundred and forty-four patients were included in the association analysis of which, 18 (12.5%) developed L-ASP hypersensitivity. Though the frequency of hypersensitivity was higher in patients that carried the risk alleles of the three investigated genes, no statistically significant differences were observed. Association analysis between PNPLA3 rs738409 and liver function could not be investigated due to a lack of clinical information.

Conclusion

In conclusion, none of the tested genes did predict L-asparaginase hypersensitivity in an Ethiopian pediatric ALL patients.

Incidence and determinants of hematotoxicity in acute lymphoblastic leukemia children who received 6-mercaptopurine based maintenance therapy in Addis Ababa, Ethiopia

INTRODUCTION

The maintenance phase of acute lymphoblastic leukemia treatment is the final and longest stage of treatment, mainly focused on antimetabolite therapy. This phase is essential to eliminate residual leukemic clones and prevent relapse. However, dose-limiting hematotoxicity is a major problem during this phase resulting in dose reduction or treatment discontinuation.

OBJECTIVE

In this cohort study, the clinical features and risk factors of hematological toxicity during the maintenance phase of treatment were analyzed in pediatric patients from Ethiopia.

METHODS

A total of 160 patients from Tikur Anbessa specialized hospital were included in the study of which 142 had sufficient data available for analysis. Patient characteristics as well as information about the care-givers, sides-effects as reported by the care-givers and clinical factors were collected. Bivariable followed by multivariable analysis was performed to investigate which factors were associated with hematological toxicity during the maintenance phase.

RESULTS

During the first six months of maintenance phase treatment grade 4 neutropenia was detected in 52.8% of the patients. The risk of developing grade 4 neutropenia was increased by about two fold in children with the age of 6 years and less compared to those with the age of more than 6 years. Similarly, the rate of developing grade 4 neutropenia among children with less than 4,500 maintenance day 1 white blood cell counts was significantly higher than that of children with normal maintenance day 1 white blood cell counts (AHR 2.477, 95% CI = 1.461-4.200, p = 0.001).

CONCLUSION

In conclusion, child's age and day 1 maintenance white blood cell/absolute neutrophil counts significantly affected the occurrence of grade 4 hematotoxicity. Close monitoring for white blood cell and absolute neutrophil counts during maintenance phase treatment is recommended for early diagnosis of hematotoxicity.

Genetic variants of genes involved in thiopurine metabolism pathway are associated with 6-mercaptopurine toxicity in pediatric acute lymphoblastic leukemia patients from Ethiopia

Introduction: Genetic variation in the thiopurine S-methyltransferase (TPMT) gene by and large predicts variability in 6-mercaptopurine (6-MP) related toxicities. However, some individuals without genetic variants in TPMT still develop toxicity that necessitates 6-MP dose reduction or interruption. Genetic variants of other genes in the thiopurine pathway have been linked to 6-MP related toxicities previously. Objective: The aim of this study was to evaluate the effect of genetic variants in ITPA, TPMT, NUDT15, XDH, and ABCB1 on 6-MP related toxicities in patients with acute lymphoblastic leukemia (ALL) from Ethiopia. Methods: Genotyping of ITPA, and XDH was performed using KASP genotyping assay, while that of TPMT, NUDT15, and ABCB1 with TaqMan^® SNP genotyping assays. Clinical profile of the patients was collected for the first 6 months of the maintenance phase treatment. The primary outcome was the incidence of grade 4 neutropenia. Bivariable followed by multivariable cox regression analysis was performed to identify genetic variants associated with the development of grade 4 neutropenia within the first 6 months of maintenance treatment. Results: In this study, genetic variants in XDH and ITPA were associated with 6-MP related grade 4 neutropenia and neutropenic fever, respectively. Multivariable analysis revealed that patients who are homozygous (CC) for XDH rs2281547 were 2.956 times (AHR 2.956, 95% CI = 1.494-5.849, p = 0.002) more likely to develop grade 4 neutropenia than those with the TT genotype. Conclusion: In conclusion, in this cohort, XDH rs2281547 was identified as a genetic risk factor for grade 4 hematologic toxicities in ALL patients treated with 6-MP. Genetic polymorphisms in enzymes other than TPMT involved in the 6-mercaptopurine pathway should be considered during its use to avoid hematological toxicity.

Identification of bacterial and fungal pathogens directly from clinical blood cultures using whole genome sequencing

Bloodstream infections are a major cause of morbidity and mortality worldwide. Early administration of appropriate antimicrobial therapy can improve patient survival and prevent antimicrobial resistance (AMR). Whole genome sequencing (WGS) can provide information for pathogen identification, AMR prediction and sequence typing earlier than current phenotypic diagnostic methods. WGS was performed on 97 clinical blood specimens and matched culture isolate pairs. Specimen/isolate pairs were MLST sequence-typed and further characterization was performed on Streptococcus species. WGS correctly identified 91.7% of clinical specimens and 93.2% of matched isolates representing 35 different microbial species. MLST types were assigned for 89.9% of matched cultures and 21.7% of blood specimens, with higher success for blood culture specimens extracted within 3 days (52% characterized) than 7 days (9.3%). This study demonstrates the potential use of WGS for identification and characterization of pathogens directly from blood culture specimens to facilitate timely initiation of appropriate antimicrobial therapies.

Stress and coping strategies among parents of children with cancer at Tikur Anbessa Specialized Hospital paediatric oncology unit, Ethiopia: a phenomenological study

OBJECTIVE

This study explores sources of stress, conditions that help reduce stress levels and coping strategies among parents of children with cancer receiving chemotherapy at Tikur Anbessa Specialized Hospital (TASH) in Ethiopia.

DESIGN

A qualitative phenomenological approach was used.

SETTING

Parents of children receiving chemotherapy at the TASH paediatric oncology unit.

PARTICIPANTS

Fifteen semistructured in-depth interviews were conducted with nine mothers and six fathers of children with cancer from November 2020 to January 2021.

RESULTS

Sources of stress related to child's health condition as the severity of the child's illness, fear of treatment side effects and loss of body parts were identified. Parents mentioned experiencing stress arising from limited access to health facilities, long waiting times, prolonged hospital stays, lack of chemotherapy drugs, and limited or inadequate information about their child's disease condition and treatment. Other sources of stress were insufficient social support, stigmatisation of cancer and financial problems. Conditions decreasing parents' stress included positive changes in the child's health, receiving cancer treatment and access to drugs. Receiving counselling from healthcare providers, getting social support and knowing someone who had a positive treatment outcome also helped reduce stress. Coping strategies used by parents were religious practices including prayer, crying, accepting the child's condition, denial and communication with health providers.

CONCLUSION

The main causes of stress identified by parents of children with cancer in Ethiopia were the severity of their child's illness, expectations of poor treatment outcomes, unavailability of cancer treatment services and lack of social/financial support. Measures that should be considered to reduce parents' stress include providing psycho-oncological care for parents and improving the counselling available to parents concerning the nature of the child's illness, its treatment, diagnostic procedures and treatment side effects. It may also be helpful to establish and strengthen family support groups and parent-to-parent communication, improve the availability of chemotherapy drugs and offer more education on coping strategies.

Risk of recurrence and death in patients with breast cancer after delayed deep inferior epigastric perforator flap reconstruction

Background

Postmastectomy reconstruction using a deep inferior epigastric perforator (DIEP) flap is increasingly being performed in patients with breast cancer. The procedure induces extensive tissue trauma, and it has been hypothesized that the release of growth factors, angiogenic agonists and immunomodulating factors may reactivate dormant micrometastasis. The aim of the present study was to estimate the risk of breast cancer recurrence in patients undergoing DIEP flap reconstruction compared with that in patients treated with mastectomy alone.

Methods

Each patient who underwent delayed DIEP flap reconstruction at Karolinska University Hospital, Sweden, between 1999 and 2013, was compared with up to four controls with breast cancer who did not receive a DIEP flap. The control patients were selected using incidence density matching with respect to age, tumour and nodal status, neoadjuvant therapy and year of mastectomy. The primary endpoint was breast cancer‐specific survival. Survival analysis was carried out using Kaplan–Meier survival estimates and Cox proportional hazard regression analysis.

Results

The analysis included 250 patients who had 254 DIEP flap reconstructions and 729 control patients. Median follow‐up was 89 and 75 months respectively (P = 0·053). Breast cancer recurrence developed in 50 patients (19·7 per cent) in the DIEP group and 174 (23·9 per cent) in the control group (P = 0·171). The 5‐year breast cancer‐specific survival rate was 92·0 per cent for patients with a DIEP flap and 87·9 per cent in controls (P = 0·032). Corresponding values for 5‐year overall survival were 91·6 and 84·7 per cent (P < 0·001). After adjustment for tumour and patient characteristics and treatment, patients without DIEP flap reconstruction had significantly lower overall but not breast cancer‐specific survival.

Conclusion

The present findings do not support the hypothesis that patients with breast cancer undergoing DIEP flap reconstruction have a higher rate of breast cancer recurrence than those who have mastectomy alone.

Deep inferior epigastric perforator is safe

Abstract P4-13-14: Risk of recurrence and death in breast cancer patients after delayed deep inferior epigastric perforator flap reconstruction

PURPOSE

Post-mastectomy reconstruction using the deep inferior epigastric perforator (DIEP) flap is increasingly performed in breast cancer patients. The procedure induces large tissue trauma and it has been hypothesized that the release of growth factors, angiogenic agonists and immunomodulating factors may reactivate dormant micrometastasis. The aim of our study was to contrast the risk of breast cancer recurrence in patients undergoing DIEP reconstruction to patients treated with mastectomy alone.

PATIENTS AND METHODS

We conducted a retrospective nested case-control study. Cases were defined as breast cancer patients operated with delayed DIEP reconstruction at Karolinska University Hospital, Sweden, between 1999-2013. Three controls, defined as breast cancer patients operated with conventional mastectomy without delayed reconstruction, were matched to each case based on age, tumour stage and year of mastectomy. The primary endpoint was breast cancer-specific survival. Survival analysis was carried out by Kaplan–Meier survival estimates and Cox proportional hazard regression analysis.

RESULTS

In all, 254 cases and 729 controls were included and had a median follow up of 134 and 122 months, respectively (p=0.004). Breast cancer recurrence occurred in 50 (19.7%) cases and 174 (23.9%) controls, respectively (p=0.171). Ten-year breast cancer-specific survival was 90.7% for cases and 85.2% in controls (p=0.067). The corresponding figures for 10-year overall survival was 89.6% and 80.0%, respectively (p&lt;0.001). Higher tumor stage and positive axillary lymph nodes, but not DIEP reconstruction, were independent risk factors for death due to breast cancer.

CONCLUSION

Our findings did not support the hypothesis that breast cancer patients undergoing DIEP reconstruction would have a higher rate of breast cancer recurrence than patients undergoing mastectomy alone.

Citation Format: Adam H, Docherty Skogh A-C, Edsander Nord Å, Schultz I, Gahm J, Hall P, Frisell J, Halle M, de Boniface J. Risk of recurrence and death in breast cancer patients after delayed deep inferior epigastric perforator flap reconstruction [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P4-13-14.

[French recommendations on control measures to reduce the infectious risk in immunocompromised patients]

The increase use of immunosuppressive treatments in patients with solid cancer and/or inflammatory diseases requires revisiting our practices for the prevention of infectious risk in the care setting. A review of the literature by a multidisciplinary working group at the beginning of 2014 wished to answer the following 4 questions to improve healthcare immunocompromised patients: (I) How can we define immunocompromised patients with high, intermediate and low infectious risk, (II) which air treatment should be recommended for this specific population? (III) What additional precautions should be recommended for immunocompromised patients at risk for infection? (IV) Which global environmental control should be recommended? Based on data from the literature and using the GRADE method, we propose 15 recommendations that could help to reduce the risk of infection in these exposed populations.

Differences in meristem size and expression of branching genes are associated with variation in panicle phenotype in wild and domesticated African rice

Background

The African rice Oryza glaberrima was domesticated from its wild relative Oryza barthii about 3000 years ago. During the domestication process, panicle complexity changed from a panicle with low complexity in O. barthii, to a highly branched panicle carrying more seeds in O. glaberrima. To understand the basis of this differential panicle development between the two species, we conducted morphological and molecular analyses of early panicle development.

Results

Using X-ray tomography, we analyzed the morphological basis of early developmental stages of panicle development. We uncovered evidence for a wider rachis meristem in O. glaberrima than in O. barthii. At the molecular level, spatial and temporal expression profiles of orthologs of O. sativa genes related to meristem activity and meristem fate control were obtained using in situ hybridization and qRT-PCR. Despite highly conserved spatial expression patterns between O. glaberrima and O. barthii, differences in the expression levels of these early acting genes were detected.

Conclusion

The higher complexity of the O. glaberrima panicle compared to that of its wild relative O. barthii is associated with a wider rachis meristem and a modification of expression of branching-related genes. Our study indicates that the expression of genes in the miR156/miR529/SPL and TAW1 pathways, along with that of their target genes, is altered from the unbranched stage of development. This suggests that differences in panicle complexity between the two African rice species result from early alterations to gene expression during reproductive development.

Electronic supplementary material

The online version of this article (doi:10.1186/s13227-017-0065-y) contains supplementary material, which is available to authorized users.

miR2118-triggered phased siRNAs are differentially expressed during the panicle development of wild and domesticated African rice species

BACKGROUND

Rice exhibits a wide range of panicle structures. To explain these variations, much emphasis has been placed on changes in transcriptional regulation, but no large-scale study has yet reported on changes in small RNA regulation in the various rice species. To evaluate this aspect, we performed deep sequencing and expression profiling of small RNAs from two closely related species with contrasting panicle development: the cultivated African rice Oryza glaberrima and its wild relative Oryza barthii.

RESULTS

Our RNA-seq analysis revealed a dramatic difference between the two species in the 21 nucleotide small RNA population, corresponding mainly to miR2118-triggered phased siRNAs. A detailed expression profiling during the panicle development of O. glaberrima and O. barthii using qRT-PCRs and in situ hybridization, confirmed a delayed expression of the phased siRNAs as well as their lncRNA precursors and regulators (miR2118 and MEL1 gene) in O. glaberrima compared to O. barthii. We provide evidence that the 21-nt phasiRNA pathway in rice is associated with male-gametogenesis but is initiated in spikelet meristems.

CONCLUSION

Differential expression of the miR2118-triggered 21-nt phasiRNA pathway between the two African rice species reflects differential rates of determinate fate acquisition of panicle meristems between the two species.

Micafungin as primary antifungal prophylaxis in patients presenting with acute myeloid leukemia

OBJECTIVE

To study the efficacy and safety of micafungin for prophylaxis of invasive fungal infections in patients undergoing induction chemotherapy for acute myeloid leukemia.

PATIENTS AND METHODS

A prospective observational single-center study of 41 patients from the hematology department between May 2012 and April 2015. Micafungin was administered once daily from the first day of induction chemotherapy to the end of the neutropenic phase.

RESULTS

Neither Candida nor Aspergillus infection was documented in our 41 patients from the first day of micafungin infusion to the end of the neutropenic phase. Patients were followed for three months after discontinuation of micafungin and none of them contracted an invasive fungal infection. Only one patient presented with grade III-IV hepatic and ionic toxicities.

CONCLUSION

Micafungin is associated with a good safety profile and is an interesting option for preventing invasive fungal infections in the high-risk population of patients presenting with hematological disorders.

Re-evaluation of rejection criteria for endotracheal tube (ETT) specimens from adult patients

The purpose of this study was to determine optimal criteria for microbiology laboratory screening of endotracheal tube (ETT) specimens submitted for bacterial culture from adult patients. ETT specimens from adult patients that were received by two microbiology laboratories were prospectively evaluated and subdivided into one of three study arms with the following criteria: <10 squamous epithelial cells (SECs) per low-power field with bacteria seen on Gram staining (arm 1), >10 SECs per low-power field with bacteria seen on Gram staining (arm 2) and <10 SECs per low-power field with no bacteria seen on Gram staining (arm 3). A fourth study arm (>10 SECs per low-power field with no bacteria seen on Gram staining) was planned but this arm was terminated due to the paucity of specimens meeting these criteria. Isolate evaluation was performed using standard microbiology protocols. A limited chart review was undertaken at one of the institutions, only reviewing patients from which a potential pathogen was recovered on culture. In total, 141 ETT specimens were evaluated. A potential respiratory pathogen was recovered from 54, 37 and 10 % of specimens in study arms 1, 2, and 3, respectively (P<0.0001, comparing between arm 1 and arm 3). For the 23 patients included in the chart review from whom a potential pathogen was recovered on culture, respiratory infection was considered to be present in 50 % (6/12) of patients in arm 1, 66.6 % (6/9) of patients in arm 2 and 100 % (2/2) of patients in arm 3. Therapy was rarely altered based on culture results. In this study, the ETT specimens submitted for bacterial culture were of limited benefit to clinicians. The data presented here support the use of an absence of bacteria on Gram staining as a rejection criterion for ETT specimens. The criterion of >10 SECs per low-power field should be further evaluated in a prospective study of patients with an unequivocal clinical diagnosis of pneumonia.

Change in antimicrobial susceptibility of Escherichia coli urinary tract isolates at a single institution over a period of 10 years

Urinary tract infections are common. Few published studies have demonstrated the change in Escherichia coli urinary isolate antimicrobial susceptibility over time within a given area and (or) population. The purpose of this study was to evaluate the change in susceptibility of E. coli clinical isolates obtained from urine specimens at a single institution over a period of 10 years. The microbiology laboratory information system at St. Boniface Hospital (Winnipeg, Manitoba, Canada) was searched retrospectively from 1 January 2000 to 31 December 2009, for all E. coli isolates from either a midstream or catheter urine source that had susceptibility testing performed. Only one isolate per patient was included during the entire study period. Antimicrobial susceptibility testing was carried out with either a Microscan instrument (pre-April 2004) or a Vitek instrument (May 2004 onwards). In total, 7353 E. coli urinary isolates were included for evaluation. Ciprofloxacin susceptibility declined significantly, from 99% in 2000 to 85% in 2009 (p < 0.0001). A small but statistically significant decline in susceptibility was also observed for ampicillin, cefazolin, trimethoprim-sulfamethoxazole, gentamicin, and nitrofurantoin. These data suggest that certain antimicrobials recommended for the treatment of urinary tract infections (ciprofloxacin, trimethoprim-sulfamethoxazole) may no longer be optimal.

The endocrine status of gossypol - treated male rats

Male adult Wistar rats were exposed daily or every other day to oral gossypol acetic acid (GAA) concentrations of 2.5-30 mg/kg for 10-20 weeks. Controls received the GAA-suspension medium or were left completely untreated. The serum concentrations of testosterone, LH and FSH as well as the weight of testis, epididymis, prostate, seminal vesicle, coagulating gland, and pituitary were determined. The accessory sex organs were prepared for light microscopy. Significant antifertility effect in these animals was achieved at GAA-dosage of 15 mg/kg and higher. GAA-administration neither altered the serum hormonal profiles nor the reproductive organ weights in comparison to the controls. Accordingly, light microscopical examination revealed no alterations in the histological picture of prostate, seminal vesicle and coagulating gland when compared with the controls. The results indicate that GAA does not interfere with the hypothalamic-pituitary-gonadal axis in male adult rats.

Conversion from carbamazepine or oxcarbazepine to topiramate in adolescents and adults with epilepsy

OBJECTIVE

To explore effectiveness, tolerability and changes in quality of life in patients with epilepsy converting to topiramate (TPM) from carbamazepine (CBZ) or oxcarbazepine (OXC) due to insufficient effectiveness and/or tolerability.

METHODS

A multicenter, open-label, non-interventional trial was used to examine patients (> or = 12 years) with epilepsy, changing to TPM monotherapy from baseline mono- or combination therapy with CBZ or OXC. TPM was added to the existing antiepileptic drug (AED) treatment and started at a dose of 25 mg once daily. The dose was titrated up with 25 mg/day increments, once every 1-2 weeks, until a final dose between 50 and 200 mg/day was reached. On the basis of clinical judgment, the treating physician decided whether or not the existing AED treatment with CBZ or OXC could then be withdrawn. Type and number of seizures, preferred TPM dose, quality of life (QOLIE-10 questionnaire), subjective perception of improvement and adverse events (AE) were documented.

RESULTS

140 patients (53.5% women, mean age 47 years) decided to switch to TPM due to insufficient effectiveness (75% of patients) and/or poor tolerability (80%) of the CBZ/OXC treatment. Average duration of follow-up was 24 weeks with an overall discontinuation rate of 19.3%, mainly due to AEs (12.1%). At study endpoint, the intended shift to TPM monotherapy was achieved in 73% of patients at a median TPM dose of 100 mg/day. A seizure reduction of > or = 50% was achieved in 91% of patients in the last scheduled period (weeks 12-26); 62% of patients entering that period remained seizure free. Quality of life at endpoint improved significantly when compared with baseline for all domains of QOLIE-10 (P < 0.001). Most frequent AEs (reported by > or = 5% of patients) were paresthesia (9.3%), weight loss (7.9%), convulsions (5.7%) and memory disorders (5.0%).

CONCLUSION

In patients with epilepsy, previously not satisfactorily treated with CBZ or OXC, conversion to TPM may result in an improvement in seizure control as well as in quality of life.

Analysis of the VEGF family and their receptors in serum/plasma of patients with pre-invasive and invasive cervical cancer

5016

Background: The vascular endothelial growth factor (VEGF) family and their receptors are essential regulators of angiogenesis and lymphangiogenesis. This study examined the significance of circulating VEGF, VEGF-C, VEGF-D and their receptors VEGFR-1 and VEGFR-2 in patients with preinvasive and invasive cancer in relation to conventional prognostic parameters. Methods: Blood samples were obtained from 125 women before initial treatment (CIN I-III n = 50; FIGO stage I-IV n = 51; relapse n = 24). Plasma (p) and serum(s) levels of pVEGF, sVEGF-D, sVEGFR-1, sVEGFR-2 (R&D Systems, USA) and sVEGF-C (IBL, Japan) were determined by using a quantitative sandwich enzyme-linked immunosorbent assay (ELISA). Results: The highest level of pVEGF (p = 0.007) and sVEGFR-2 (p = 0.014) were detected in patients with recurrent disease, whereas the highest level of sVEGF-D (p = 0.046) were measured in patients with preinvasive lesions (CIN I-III). Furthermore, significantly elevated levels of sVEGF-C (p = 0.021) were detected in early stages (FIGO I-II) in comparison with advanced stages (FIGO III-IV) of cervical cancer. No significant difference in concentration was observed between the various grades of cervical intraepithelial neoplasia (CIN I-III). Correlations between conventional prognostic markers such as lymph node status (N0/N1), lymphangioinvasion (L0/L1), angioinvasion (V0/V1) and grading (G1/G2/G3) were investigated. Increased plasma levels of VEGF (p = 0.036) correlate with the dissemination of tumor cells to regional lymph nodes (N1),whereas serum VEGF-D levels were significantly decreased in women with lymph-node involvement (N1) (p = 0.045) and vascular invasion (L1) (p = 0.019). None of these members of the VEGF family were found to correlate significantly with histological subtype (squamous cell carcinoma, adenocarcinoma, adeno-squamous cell carcinoma) or grading of the tumor cells (G1/G2/G3). Conclusions: These results show that circulating concentrations of VEGF are associated with the stage of disease. In an early stage of cervical cancer a switch to a lymphangiogenic phenotype (VEGF-D, VEGF-C) might be possible.

No significant financial relationships to disclose.

Cost analysis of ELISA, solid-phase extraction, and solid-phase microextraction for the monitoring of pesticides in water

The implementation of a pesticide water monitoring program in South Africa is limited by a lack of financial and analytical resources. A cost analysis of three analytical methods, enzyme-linked immunosorbent assays (ELISA), solid-phase microextraction (SPME), and traditional solid-phase extraction methods (SPE), was conducted. The cost analysis assumed a hypothetical scenario in terms of the sampling area (a grape farming rural region in the Western Cape province of South Africa), sample collection (weekly grab samples collected from eight sites by an environmental health officer in a nearby town), transport of samples (via courier), and analysis (endosulfan and chlorpyrifos analysis conducted by a local higher educational institution laboratory in Cape Town). The cost per sample for the three analytical methods was determined by estimating the annual capital costs, including building and equipment, and recurrent costs, including transport, personnel, supplies, and building operating costs. At the optimal utility of resources, SPME had the lowest cost per sample (US $37), followed by SPE (US $48.50) and ELISA (US $60). Recurrent costs formed the bulk of the costs of all three methods (91-97%). The cost of supplies was particularly high for ELISA (US $34 per sample). The cost per sample estimated for all three methods is substantially lower than those quoted by other laboratories in South Africa. The low cost of SPME is particularly important because of the sensitivity and reliability of this method and the faster output compared to SPE, and SPME is recommended for the long-term monitoring of pesticide pollution.

[Vertical infraclavicular technique of brachial plexus block]

In comparison to preceding infraclavicular methods, vertical infraclavicular blockade of the brachial plexus (VIP), as described by Kilka et al. in 1995, has quickly established itself because of the high success rates and comparatively low risks. Users define the blockade success achieved at around 85 %. However, this figure includes a more or less large number of patients who require supplementary analgesia/sedation and/or sleep induction in addition to pre-medication. Such a combined procedure, VIP plus analgesia/sedation is sometimes problematic e. g. in geriatric patients with a number of additional diseases. This patient group in particular could possibly profit from VIP without additional medication. Based initially on purely clinical observations, the following study reports on a method to improve the success rate of VIP blockade (operability) without additional analgesia and/or sedation. Altogether 499 patients were included in a retrospective study. In 88 patients (Group 1), the method of Kilka et al. was strictly applied. In a second Group (99 patients) the determined puncture site was moved 1 cm laterally. In Group 3 (312 patients), elicitation of a response to stimulation of the fasciculi of the brachial plexus was examined. This was performed by multiple punction, as a rule lateral to the puncture site of Kilka et al. In this group, the total dose of anesthetic (identical in all groups) was divided into 2 - 3 single doses. The pre-operative data of the patients in all groups were comparable. In the course of the VIP (Group 1), the method was changed in 13 patients (14.8 %) with incomplete blockade and after initial modification (Group 2), this was necessary in 12 patients (12.1 %). By means of targeted stimulation of individual sections of the brachial plexus (Group 3), the rate of incomplete blockade could be reduced to 8.3 %. The clearly improved blockade success was achieved without an increase in complications. In contrast to other authors, we came to the conclusion that the success rate was considerably higher when the anaesthetist had several years of experience. In the case of the authors of this study (longest experience), only 3.7 % of the plexus blocks were incomplete. For the use of VIP in practice it can be concluded that the optimal puncture site is often somewhat lateral to that defined by Kilka et al. By means of multiple stimulation with the aim of locating the individual fasciculi of the brachial plexus, the success of blockade, in terms of operability with unchanged low complication rates, can be considerably improved without the need for additional analgesics and/or sedation.

[Angle closure glaucoma in association with relative anterior microphthalmus (RAM) after premature birth-retinopathy (ROP)]

BACKGROUND

The infantile angle-closure glaucoma is a common and well characterized complication of retinopathy of prematurity (ROP). Progressive shallowing of the anterior chamber by retrolental fibrous masses is mostly responsible for the pressure elevation during the first years of life. Apart of this pathogenesis, ROP-associated glaucoma is totally different in cases that do not manifest until adulthood. Only few cases are described in the literature.

CASE REPORT

A 36-year-old female patient presented with symptoms of acute intraocular pressure (IOP) elevation and fundus results of a cicatricial ROP stadium II. Control of IOP was not achieved by systemic and topical drug treatment. The biometry showed a relative anterior microphthalmus (RAM) in myopia. After peripheral iridectomy, the IOP normalized and remained stable over a long-time period.

CONCLUSION

Myopia induction after ROP and ROP treatment often lead to special anatomical conditions corresponding to the classical relative anterior microphthalmus. Shallowing of the anterior chamber and development of angle-closure glaucoma increase with age. Thus, a manifestation not before the third decade of life was a typical finding in the literature review. A detailed recording of history and consideration of the biometric data are of importance for diagnosis. Peripheral iridectomy was found to be the therapy with the highest success rate. The increase of a pupillary block mechanism can prevent further visual loss to the often pre-damaged eyes. Consideration of this entity is crucial in unilateral IOP elevation, because an increasing prevalence of these patients can be expected due to the increase of premature babies since 1970.

[Anesthesia for section caesarean with aortic dissection in Marfan Syndrome]

Marfan Syndrome (MFS) is associated with an increased anaesthesia risk because of the pathological manifestations in anaesthesia-relevant organ systems. If, in addition, a typical MFS complication - acute aortic dissection - presents and this in pregnant patients, a high-risk anaesthesia must be assumed. In the case reported, a 30 year old woman in the 35 th week of gestation presented with an acute aortic dissection, initially in the region of the descending aorta and later, in the course of the ascending aorta. An urgent Caesarean section was indicated in order to perform the equally urgent vascular surgery as quickly as possible. The most important goal of the anaesthesia management is to determine an anaesthesia procedure which addresses the combination of aorta dissection, gestation and MFS. On the one hand, the risk of an aorta rupture needs to be kept as low as possible and on the other hand, the vital functions of the baby have to be maintained. A general anaesthesia procedure under mild controlled hypotension was selected. Optimal monitoring and absolute freedom from pain were the prerequisites both for the anaesthesia management of the Caesarean section as well as for the immediate transport to a clinic for further treatment after completion of anaesthesia.

[Fantoni translaryngeal tracheotomy (TLT) with rigid endoscopic control]

RATIONALE

The incidence of translaryngeal tracheotomy (TLT)-associated peri- and postoperative complications should be assessed prospectively.

METHODS

TLT was carried out in operation-theatre under rigid endoscopic control. Peri- and postoperative complications, decanulement and late sequelae were assessed in ENT-patients. In patients of other wards only perioperative complications were evaluated.

RESULTS

41 patients (26 ENT-patients, 15 patients of other wards) were tracheotomised by TLT. Perioperatively, we observed 3 technical problems (accidental pulling through of the tracheostomy tube). In 2 of these cases TLT could be completed without problems, in 1 case TLT was converted to surgical tracheotomy. Postoperatively, we could find no complications in 26 ENT-patients. Decanulation took place after 7 days on average. We found no tracheocutaneous fistulas or tracheostenoses, scars were unobtrusive.

CONCLUSIONS

TLT with rigid endoscopy is a simple percutaneous tracheotomy-technique with a low complication rate.

A simple method for the identification and assay of extracellular plant beta-galactosidase

A simple, rapid and reproducible procedure for the identification of extracellular Californian poppy (Eschscholzia californica Cham.) beta-galactosidase is described using callus cultures of seedlings from the tested plant, roots of 4-days-old seedlings of Californian poppy germinating on agar plates and cell suspension cultures cultivated from callus cultures. 6-Bromo-2-naphthyl-beta-D-galactopyranoside and p-nitrophenyl-beta-D-galactopyranoside were used as substrates for the determination of the intracellular and extracellular activities of beta-galactosidase. The extracellular beta-galactosidase activity was identified by evaluating the dye-zones in an agar medium. The enzyme from Californian poppy callus cultures or from seedling roots cultivated on agar plates supplemented with 6-bromo-2-naphthyl-galactopyranoside hydrolyzed this substrate releasing 6-bromo-2-naphthol. By simultaneous coupling with hexazonium p-rosaniline the corresponding (reddish-brown) azo-dye was formed. The agar plate method described permits rapid, simple and specific detection of plant producers of extracellular beta-galactosidase.

Association between severity of atopic eczema and degree of sensitization to aeroallergens in schoolchildren

BACKGROUND

A subgroup of patients with atopic eczema exhibits aggravation through contact with aeroallergens. Little is known from population-based studies, however, about the association between the severity of eczematous skin disease and the degree of aeroallergen sensitization.

OBJECTIVE

We sought to investigate the relationship between IgE-mediated allergic sensitization to aeroallergens and severity of atopic eczema in schoolchildren.

METHODS

A nested case-control analysis on atopic eczema was performed on the basis of a cross-sectional study of 2201 East German schoolchildren aged 5 to 14 years. Atopic eczema and its severity was identified by dermatologic examination. Total and allergen-specific IgE antibodies to grass and birch pollen, Cladosporium herbarum, Dermatophagoides pteronyssinus, and cat epithelium in serum were determined, and additional information was obtained by means of standardized questionnaire.

RESULTS

The overall prevalence of actual atopic eczema was 2.5%. Thirty-seven percent of the children were sensitized to at least one allergen. Children with atopic eczema were significantly more often sensitized than those without skin disease (75.0% vs 36.3%; odds ratio, 5.27; 95% confidence interval, 2.54-11.15). This was observed for each single allergen. The prevalence of atopic eczema increased significantly with increasing RAST class (chi(2) trend test for each allergen, P <.0001). Also, the prevalence of sensitization increased with the severity of the disease (chi(2) trend test for each allergen, P <.0001). This association was pronounced for house dust mite and cat allergen. Multiple linear regression analyses showed significant associations between the severity score of atopic eczema and concentrations of allergen-specific IgE to dust mite (P =.032) and cat (P =.014) allergens after adjustment for sex, age, location, and parental predisposition.

CONCLUSIONS

The degree of sensitization is directly associated with the severity of atopic eczema. We speculate that early epicutaneous sensitization to aeroallergens may be enhanced by damage of the skin barrier function. The specific IgE response seems to contribute to the severity of the disease in a dose-dependent fashion.

Indoor risk factors for atopic eczema in school children from East Germany

This study aimed to investigate the relation between environmental influences such as arsenic, cadmium, lead, and mercury, as well as environmental tobacco smoke, pet keeping, and heating systems on the prevalence of atopic eczema. Therefore, a multicenter cross-sectional study of school children aged 5-14 years, including a standardized questionnaire, blood and urine analyses, and a dermatological examination, was undertaken. A cases-control approach was chosen in order to identify relevant risk factors. A total of 2200 school children (response 79.1%) of two areas (Bitterfeld, Hettstedt) polluted by industrial activities and an agricultural control region (Zerbst) of the former German Democratic Republic were examined. Atopic eczema as identified by dermatological examination and history was the outcome variable of interest. Body burden of arsenic and heavy metals and questionnaire data on environmental tobacco smoke exposure, pet keeping, and heating system were investigated as potential risk factors. The overall prevalence of atopic eczema was 2.6%, with higher prevalences in the industrial areas (2.5 and 2.9%) compared to the control area (1.6%, not significant). Bivariate analyses did not reveal statistically significant associations between atopic eczema and tobacco smoke exposure or the body burden of arsenic and heavy metals. According to multiple logistic regression analysis, atopic eczema was significantly more frequent in predisposed families and those who reported keeping guinea pigs (OR=4.37, CI 2.15-8.91), but not other pets, like dogs, cats, and hamsters. In comparison to a distant heating system, a decreased risk was observed in households with central heating system (OR=0.30, CI 0.10-0.90), whereas the presence of a gas heater with an exhaust pipe connection to the wall was associated with a significantly elevated risk for eczema (OR=8.22, CI 2.44-27.66). The heating system and exposure to certain animal allergens are related to the manifestation of atopic eczema. Further studies are needed to clarify how far a causal relationship is reflected by these findings.

[Anagrelide in control of myeloproliferative thrombocythemia: long-term experiences in 6 patients]

Symptomatic or asymptomatic chronic elevation of platelet count can be observed in all forms of myeloproliferative disorders (MPD). Benefits and limitations of the traditional platelet-reducing agents, such as radioactive phosphorus, alkylating agents, hydroxyurea and interferon alpha, are well known and have been largely described. Anagrelide (Agrelin) is an additional newer drug with a selective platelet-lowering effect. We describe our own long-term experience in 6 patients with MPD who were treated with anagrelide as part of a compassionate-use protocol between April 1991 and August 1997. The median duration of therapy was 54 months (range 17 to 75 months), with an overall response rate of 100% (complete and partial response for at least 4 weeks). The initial median platelet count of 1211 x 10(9)/l (range 847 to 2050 x 10(9)/l) was reduced rapidly and lastingly to 570 x 10(9)/l (range 216 to 667 x 10(9)/l) at the time of the last control. Under treatment with anagrelide 4 of the 6 patients showed a reduction of disease-associated symptoms or complications. Adverse reactions were generally mild and transitory, and no interruption or cessation of therapy was required. Development of drug resistance or late adverse events were not observed. Treatment with anagrelide is effective, safe and in our opinion easy to administer. It also appears to be suitable for long-term administration.

Nitric oxide and ocular blood flow in patients with IDDM

Endothelial dysfunction has been implicated in the pathogenesis of diabetic vascular disorders such as diabetic retinopathy. We hypothesized that either local endogenous nitric oxide (NO) synthesis or local reactivity to endogenous NO might be impaired in patients with IDDM and that this may contribute to the development of diabetic retinopathy. Ten otherwise healthy patients with long-standing IDDM and ten healthy control subjects were studied according to an open randomized two-way cross-over design. Subjects received intravenous infusions of either N(G)-monomethyl-L-arginine, an inhibitor of NO-synthase, or L-arginine, the precursor of NO synthesis, on two separate study days. Ocular hemodynamics were assessed by laser interferometric measurement of fundus pulsations and Doppler sonographic measurement of blood flow velocity in the ophthalmic artery. N(G)-monomethyl-L-arginine decreased fundus pulsations and blood flow velocity in the ophthalmic artery and increased blood pressure in healthy subjects. The responses to NO-synthase inhibition were significantly less in diabetic subjects. In contrast, L-arginine caused a comparable increase in fundus pulsations and decrease in blood pressure in both cohorts. These results indicate that systemic and ocular hemodynamic reactivity to NO-synthase inhibition is reduced in patients with long-standing IDDM, compared with healthy control subjects. Thus, this study indicates that either NO-synthase activity is increased or NO sensitivity is decreased in patients with IDDM and supports the concept of an involvement of the L-arginine-NO system in the pathophysiology of diabetic retinopathy.

[Current legislation in public health--an example for post-modern social ethics?]

Social ethics of affirmative postmodernists are discussed in relation to recent German health care legislation. It could be shown that: 1. the health care legislation 1989 and 1993 only partially fulfills the postmodern call for "cultivation of individual responsibility", 2. both laws largely fail to enforce the principle of subsidiarity, and 3. postmodernist thinking is weak on the question of global strategies but strong In the area of individualism and subjectivity. We conclude that postmodern social ethics are useful to compensate areas largely neglected by recent German health care legislation, rather than that the legislation is an example of postmodern social ethics.

Measles antibody in vaccinated human immunodeficiency virus type 1-infected children

OBJECTIVES

The goals of this study were to evaluate the proportion of previously vaccinated human immunodeficiency virus (HIV) type 1-infected children with detectable postvaccination measles antibody; to assess risk factors for vaccine failure; and to evaluate the response to reimmunization.

METHODS

A total of 81 perinatally HIV-infected children receiving medical care in the Bronx, New York who had previously received measles vaccine were enrolled. The Centers for Disease Control and Prevention (CDC) HIV class, lymphocyte subsets, and measles antibody were determined upon enrollment. Additional data abstracted from medical records included dates and number of prior measles vaccinations and CDC HIV class at the time of vaccination. Measles antibody was determined by microneutralization enzyme-linked immunosorbent assay (ELISA).

RESULTS

The median age at time of study was 42 months (range, 9 to 168 months). Overall, 58 (72%) subjects had detectable measles antibody (microneutralization ELISA titer > 1:5). Children studied within 1 year of vaccination were more likely to have detectable measles antibody than children evaluated more than 1 year after vaccination (83% vs 52%, P < .01). The proportion of children with detectable measles antibody was higher among children with no or moderate immunosuppression compared to those with severe immunosuppression when immune status was based on CD4%. Children vaccinated at 6 to 11 months of age appeared to have a higher proportion of detectable measles antibody than those who received a first measles vaccination after age 1. Only 1 (14%) of 7 previously vaccinated children who were seronegative or had very low titers experienced a four-fold rise in measles antibody when reimmunized.

CONCLUSION

These results support current recommendations to vaccinate HIV-infected children against measles. The proportion of children with detectable measles antibody among vaccinated HIV-infected children is considerably lower than in vaccinated healthy children. HIV-infected children may respond better to measles vaccine when it is administered before the first birthday. From our limited data it appears that reimmunization of previously vaccinated HIV-infected children with moderate to severe immunosuppression does not result in an antibody recall response.

Ontogenic expression of the erythroid-type glucose transporter (Glut 1) in the telencephalon of the mouse: correlation to the tightening of the blood-brain barrier

Since Glut 1 was shown to be highly abundant in brain microvessels, its distribution during early developmental stages seems of importance in respect to the timing of blood-brain barrier (bbb) formation in the developing CNS. Here we have followed the temporal expression of the erythroid-type glucose transporter Glut 1 in the telencephalon of the embryonic and newborn mouse, beginning at the 9th intrauterine day. Glut 1 immunofluorescence staining was done on cryosections using a rabbit polyclonal antiserum to purified human erythrocyte glucose transporter. Endothelial cells resp. capillaries were detected by staining with a rhodamin-coupled Bandeiraea simplicifolia lectin (BSL). In parallel, the developmental tightening of the embryonic bbb was assessed by perfusion of mouse embryos with Trypan blue and horse radish-peroxidase. At E9, prior to the onset of intraneural neovascularization, strong Glut 1 immunoreactivity was found in the whole neuroectoderm but only minor staining was seen in the perineural domain. Glut 1 expression remained uniformly distributed in the intraneural tissue at E10, the beginning of intraneural neovascularization in the mouse. From E11 onwards, Glut 1 immunoreactivity was invisible in neuroepithelial cells, but appeared tightly associated with intraneural capillaries. Perfusion of E12 embryos using trypan blue solution and HRP revealed that most parts of the CNS and spinal cord were impermeable to the tracer substances at that stage. Thus, we suggest that the bbb is established very early in CNS development, probably in the course of intraneural neovascularization. In addition, our data indicate that the restriction of Glut 1 expression to the intraneural capillaries reflects the onset of bbb function in the mouse embryo.