Risk factors for asthma in inner city children

Inner city children have the highest prevalence and the highest mortality rates for asthma in the United States. The purpose of this study was to evaluate sensitization and exposure to common indoor allergens among children aged 3 years to 15 years seen for treatment of asthma at Grady Memorial Hospital, Atlanta, Ga. Eighty children in this study were enrolled in the emergency department and 64 in hospital clinics. Dust from 57 homes, assayed for three indoor allergens (dust mite, cat, and cockroach), revealed similar exposure for asthma and control groups. Sixty-nine percent of the children with asthma had IgE antibodies to dust mite, cockroach, or cat; only 27% of the control subjects were similarly sensitized (p < 0.001). Of 35 children with asthma 21 had both sensitization and significant exposure to the relevant allergen; this was true for only 3 of 22 control subjects (odds ratio, 9.5; p < 0.001). Neither sensitization nor exposure to cat allergen was common in this population. The results show that black children in inner city Atlanta are exposed to high levels of mite and cockroach allergens and that a high proportion of the children with asthma are sensitized to these allergens; the combination of sensitization and exposure is a major risk factor for asthma in this population.

Coronavirus in pregnancy and delivery: rapid review

OBJECTIVES

There are limited case series reporting the impact on women affected by coronavirus during pregnancy. In women affected by severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS), the case fatality rate appears higher in those affected in pregnancy compared with non-pregnant women. We conducted a rapid review to guide health policy and management of women affected by COVID-19 during pregnancy, which was used to develop the Royal College of Obstetricians and Gynaecologists' (RCOG) guidelines on COVID-19 infection in pregnancy.

METHODS

Searches were conducted in PubMed and MedRxiv to identify primary case reports, case series, observational studies and randomized controlled trials describing women affected by coronavirus in pregnancy. Data were extracted from relevant papers. This review has been used to develop guidelines with representatives of the Royal College of Paediatrics and Child Health (RCPCH) and RCOG who provided expert consensus on areas in which data were lacking.

RESULTS

From 9965 search results in PubMed and 600 in MedRxiv, 21 relevant studies, all of which were case reports or case series, were identified. From reports of 32 women to date affected by COVID-19 in pregnancy, delivering 30 babies (one set of twins, three ongoing pregnancies), seven (22%) were asymptomatic and two (6%) were admitted to the intensive care unit (ICU), one of whom remained on extracorporeal membrane oxygenation. No maternal deaths have been reported to date. Delivery was by Cesarean section in 27 cases and by vaginal delivery in two, and 15 (47%) delivered preterm. There was one stillbirth and one neonatal death. In 25 babies, no cases of vertical transmission were reported; 15 were reported as being tested with reverse transcription polymerase chain reaction after delivery. Case fatality rates for SARS and MERS were 15% and 27%, respectively. SARS was associated with miscarriage or intrauterine death in five cases, and fetal growth restriction was noted in two ongoing pregnancies affected by SARS in the third trimester.

CONCLUSIONS

Serious morbidity occurred in 2/32 women with COVID-19, both of whom required ICU care. Compared with SARS and MERS, COVID-19 appears less lethal, acknowledging the limited number of cases reported to date and that one woman remains in a critical condition. Preterm delivery affected 47% of women hospitalized with COVID-19, which may put considerable pressure on neonatal services if the UK's reasonable worst-case scenario of 80% of the population being affected is realized. Based on this review, RCOG, in consultation with RCPCH, developed guidance for delivery and neonatal care in pregnancies affected by COVID-19, which recommends that delivery mode be determined primarily by obstetric indication and recommends against routine separation of affected mothers and their babies. We hope that this review will be helpful for maternity and neonatal services planning their response to COVID-19. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology.

A randomized comparison between rasburicase and allopurinol in children with lymphoma or leukemia at high risk for tumor lysis

Standard therapy in the United States for malignancy-associated hyperuricemia consists of hydration, alkalinization, and allopurinol. Urate oxidase catalyzes the enzymatic oxidation of uric acid to a 5 times increased urine soluble product, allantoin. Rasburicase is a new recombinant form of urate oxidase available for clinical evaluation. This multicenter randomized trial compared allopurinol to rasburicase in pediatric patients with leukemia or lymphoma at high risk for tumor lysis. Patients received the assigned uric acid-lowering agent for 5 to 7 days during induction chemotherapy. The primary efficacy end point was to compare the area under the serial plasma uric acid concentration curves during the first 96 hours of therapy (AUC(0-96)). Fifty-two patients were randomized at 6 sites. In an intent-to-treat analysis, the mean uric acid AUC(0-96) was 128 +/- 70 mg/dL.hour for the rasburicase group and 329 +/- 129 mg/dL.hour for the allopurinol group (P <.0001). The rasburicase versus allopurinol group experienced a 2.6-fold (95% CI: 2.0-3.4) less exposure to uric acid. Four hours after the first dose, patients randomized to rasburicase compared to allopurinol achieved an 86% versus 12% reduction (P <.0001) of initial plasma uric acid levels. No antirasburicase antibodies were detected at day 14. This randomized study demonstrated more rapid control and lower levels of plasma uric acid in patients at high risk for tumor lysis who received rasburicase compared to allopurinol. For pediatric patients with advanced stage lymphoma or high tumor burden leukemia, rasburicase is a safe and effective alternative to allopurinol during initial chemotherapy.

Post-Transcriptional Genetic Silencing of BCL11A to Treat Sickle Cell Disease

BACKGROUND

Sickle cell disease is characterized by hemolytic anemia, pain, and progressive organ damage. A high level of erythrocyte fetal hemoglobin (HbF) comprising α- and γ-globins may ameliorate these manifestations by mitigating sickle hemoglobin polymerization and erythrocyte sickling. BCL11A is a repressor of γ-globin expression and HbF production in adult erythrocytes. Its down-regulation is a promising therapeutic strategy for induction of HbF.

METHODS

We enrolled patients with sickle cell disease in a single-center, open-label pilot study. The investigational therapy involved infusion of autologous CD34+ cells transduced with the BCH-BB694 lentiviral vector, which encodes a short hairpin RNA (shRNA) targeting BCL11A mRNA embedded in a microRNA (shmiR), allowing erythroid lineage-specific knockdown. Patients were assessed for primary end points of engraftment and safety and for hematologic and clinical responses to treatment.

RESULTS

As of October 2020, six patients had been followed for at least 6 months after receiving BCH-BB694 gene therapy; median follow-up was 18 months (range, 7 to 29). All patients had engraftment, and adverse events were consistent with effects of the preparative chemotherapy. All the patients who could be fully evaluated achieved robust and stable HbF induction (percentage HbF/(F+S) at most recent follow-up, 20.4 to 41.3%), with HbF broadly distributed in red cells (F-cells 58.9 to 93.6% of untransfused red cells) and HbF per F-cell of 9.0 to 18.6 pg per cell. Clinical manifestations of sickle cell disease were reduced or absent during the follow-up period.

CONCLUSIONS

This study validates BCL11A inhibition as an effective target for HbF induction and provides preliminary evidence that shmiR-based gene knockdown offers a favorable risk-benefit profile in sickle cell disease. (Funded by the National Institutes of Health; ClinicalTrials.gov number, NCT03282656).

Root branching toward water involves posttranslational modification of transcription factor ARF7

Plants adapt to heterogeneous soil conditions by altering their root architecture. For example, roots branch when in contact with water by using the hydropatterning response. We report that hydropatterning is dependent on auxin response factor ARF7. This transcription factor induces asymmetric expression of its target gene LBD16 in lateral root founder cells. This differential expression pattern is regulated by posttranslational modification of ARF7 with the small ubiquitin-like modifier (SUMO) protein. SUMOylation negatively regulates ARF7 DNA binding activity. ARF7 SUMOylation is required to recruit the Aux/IAA (indole-3-acetic acid) repressor protein IAA3. Blocking ARF7 SUMOylation disrupts IAA3 recruitment and hydropatterning. We conclude that SUMO-dependent regulation of auxin response controls root branching pattern in response to water availability.

Reporting colorectal cancer

The management of colorectal cancer is a team process. High-quality reporting of colorectal cancer is very important as the whole team relies upon the skill of the pathologist. Failure to report key features can lead to undertreatment of this disease. The use of a proforma has been demonstrated to be beneficial and we recommend staying with TNM5 due to scientific and reproducibility issues with TNM6. Important features in stage II/Dukes' B cases are extramural vascular invasion, peritoneal involvement, extent of extramural spread, incomplete resection and perforation. All of these may lead to adjuvant therapy being administered. The surgically created circumferential resection margin (CRM) and the mode of its creation are important features and the CRM retains its value after preoperative therapy. Regression grading should be applied only to fully resected tumours and the dissection and sampling must be standardized to allow comparison of results between trials and centres. When reporting local resections of early-stage cancers we need to look for features that predict spread to local lymph nodes to allow a full resection to be considered.

Functional diversity in coral-dinoflagellate symbiosis

Symbioses are widespread in nature and occur along a continuum from parasitism to mutualism. Coral-dinoflagellate symbioses are defined as mutualistic because both partners receive benefit from the association via the exchange of nutrients. This successful interaction underpins the growth and formation of coral reefs. The symbiotic dinoflagellate genus Symbiodinium is genetically diverse containing eight divergent lineages (clades A-H). Corals predominantly associate with clade C Symbiodinium and to a lesser extent with clades A, B, D, F, and G. Variation in the function and interactive physiology of different coral-dinoflagellate assemblages is virtually unexplored but is an important consideration when developing the contextual framework of factors that contribute to coral reef resilience. In this study, we present evidence that clade A Symbiodinium are functionally less beneficial to corals than the dominant clade C Symbiodinium and may represent parasitic rather than mutualistic symbionts. Our hypothesis is supported by (i) a significant correlation between the presence of Symbiodinium clade A and health-compromised coral; (ii) a phylogeny and genetic diversity within Symbiodinium that suggests a different evolutionary trajectory for clade A compared with the other dominant Symbiodinium lineages; and (iii) a significantly lower amount of carbon fixed and released by clade A in the presence of a coral synthetic host factor as compared with the dominant coral symbiont lineage, clade C. Collectively, these data suggest that along the symbiotic continuum the interaction between clade A Symbiodinium and corals may be closer to parasitism than mutualism.

Unacceptable variation in abdominoperineal excision rates for rectal cancer: time to intervene?

OBJECTIVE

To determine the variation in the rates of use of abdominoperineal excision (APE) by cancer network, hospital trust and surgeon across England between 1998 and 2004 and determine if any variation could be explained by differences in patient characteristics such as stage of disease, age, gender or socioeconomic deprivation.

DESIGN

Retrospective study of a population-based dataset comprised of cancer registry and hospital episode statistics data.

SETTING

All NHS providers of rectal cancer surgery within England.

PATIENTS

31,223 patients diagnosed with rectal cancer and receiving a major abdominal procedure within the NHS in England between 1998 and 2004.

MAIN OUTCOME MEASURE

Rates and odds of use of APE were determined in relation to patient case-mix and each patient's managing surgeon, trust and cancer network.

RESULTS

The rate of use of APE decreased from 30.5% in 1998 to 23.0% in 2004. Males, the economically deprived and those managed by surgeons operating on fewer than seven rectal cancer cases per year were all significantly more likely to receive an APE. There were also significant variations in the odds of receiving an APE over time and between individual surgeons and hospital trusts independently of patient case-mix.

CONCLUSIONS

Over the study period the use of APE decreased but statistically significant variation was observed in its application independently of case mix. Reducing this variation will remove inequalities, reduce colostomy rates, and improve outcomes in rectal cancer. Rates of APE use could be a national performance measure.

Maternity services in the UK during the coronavirus disease 2019 pandemic: a national survey of modifications to standard care

OBJECTIVE

To explore the modifications to maternity services across the UK, in response to the coronavirus disease 2019 (COVID-19) pandemic, in the context of the pandemic guidance issued by the Royal College of Obstetricians and Gynaecologists (RCOG), Royal College of Midwives (RCM) and NHS England.

DESIGN

National survey.

SETTING

UK maternity services during the COVID-19 pandemic.

POPULATION OR SAMPLE

Healthcare professionals working within maternity services.

METHODS

A national electronic survey was developed to investigate local modifications to general and specialist maternity care during the COVID-19 pandemic, in the context of the contemporaneous national pandemic guidance. After a pilot phase, the survey was distributed through professional networks by the RCOG and co-authors. The survey results were presented descriptively in tabular and graphic formats, with proportions compared using chi-square tests.

MAIN OUTCOME MEASURES

Service modifications made during the pandemic.

RESULTS

A total of 81 respondent sites, 42% of the 194 obstetric units in the UK, were included. They reported substantial and heterogeneous maternity service modifications. Seventy percent of units reported a reduction in antenatal appointments and 56% reported a reduction in postnatal appointments; 89% reported using remote consultation methods. A change to screening pathways for gestational diabetes mellitus was reported by 70%, and 59% had temporarily removed the offer of births at home or in a midwife-led unit. A reduction in emergency antenatal presentations was experienced by 86% of units.

CONCLUSIONS

This national survey documents the extensive impact of the COVID-19 pandemic on maternity services in the UK. More research is needed to understand the impact on maternity outcomes and experience.

TWEETABLE ABSTRACT

A national survey showed that UK maternity services were modified extensively and heterogeneously in response to COVID-19.

Phosphatidylglycerol is involved in the dimerization of photosystem II

Photosystem II core dimers (450 kDa) and monomers (230 kDa) consisting of CP47, CP43, the D1 and D2 proteins, the extrinsic 33-kDa subunit, and the low molecular weight polypeptides PsbE, PsbF, PsbH, PsbI, PsbK, PsbL, PsbTc, and PsbW were isolated by sucrose density gradient centrifugation. The photosystem II core dimers were treated with phospholipase A2 (PL-A2), which cuts phosphatidylglycerol (PG) and phosphatidylcholine molecules at the sn-2 position. The PL-A2-treated dimers dissociated into two core monomers and further, yielding a CP47-D1-D2 subcomplex and CP43. Thin layer chromatography showed that photosystem II dimers contained four times more PG than their monomeric counterparts but with similar levels of phosphatidylcholine. Consistent with this was the finding that, compared with monomers, the dimers contained a higher level of trans-hexadecanoic fatty acid (C16:1Delta3tr), which is specific to PG of the thylakoid membrane. Moreover, treatment of dimers with PL-A2 increased the free level of this fatty acid specific to PG compared with untreated dimers. Further evidence that PG is involved in stabilizing the dimeric state of photosystem II comes from reconstitution experiments. Using size exclusion chromatography, it was shown that PG containing C16:1Delta3tr, but not other lipid classes, induced significant dimerization of isolated photosystem II monomers. Moreover, this dimerization was observed by electron crystallography when monomers were reconstituted into thylakoid lipids containing PG. The unit cell parameters, p2 symmetry axis, and projection map of the reconstituted dimer was similar to that observed for two-dimensional crystals of the native dimer.

Comparison of tibial plateau angles in dogs with and without cranial cruciate ligament injuries

OBJECTIVE

To measure and compare tibial plateau angles (TPA) of dogs with cranial cruciate ligament (CrCL) injuries and dogs without CrCL injuries.

DESIGN

Prospective study.

ANIMALS

87 dogs.

PROCEDURE

Stifle joints were measured from lateral radiographic views to determine TPA in 3 groups: group-1 dogs had CrCL injuries, group-1a dogs, a subgroup of group 1, had 1 unaffected stifle joint, and group-2 dogs had no CrCL injuries. Age, sex, breed, body weight, limb injured, and TPA were recorded for each dog.

RESULTS

56 stifle joints were measured in group-1 dogs; mean TPA was 23.76 degrees , and mean age and weight were 5.7 years and 37.91 kg (83.4 lb), respectively. Fourteen stifle joints were measured in group-1a dogs; mean TPA was 24.71 degrees , and mean age and weight were 5.6 years and 38.06 kg (83.8 lb), respectively. Sixty stifle joints were measured in group-2 dogs; mean TPA was 18.10 degrees , and mean age and weight of these dogs were 4.83 years and 35.85 kg (79 lb), respectively. The most common breeds included Labrador Retriever, Golden Retriever, and Rottweiler. The TPA of dogs in group 1 and group 1a were significantly greater than the TPA of dogs in group 2.

CONCLUSIONS AND CLINICAL RELEVANCE

Dogs with CrCL injuries have a significantly greater TPA than dogs without CrCL injury. With further investigation, a normal TPA can be determined. In the future, TPA measurements may be used to screen dogs suspected of being susceptible to CrCL injury.

Systemic neutrophil-to-lymphocyte ratio in colorectal cancer: the relationship to patient survival, tumour biology and local lymphocytic response to tumour

Background:

Colorectal cancer (CRC) is a major cause of mortality and morbidity. The impact of inflammatory biomarkers (C-reactive protein etc.) on CRC is increasingly studied including systemic neutrophil-to-lymphocyte ratio (NLR) as they seem to predict outcome.

Methods:

All patients who underwent curative resection for CRC from 2000 to 2004 at Leeds Teaching Hospitals NHS Trust had pre-operative NLR calculated. Demographic, histopathological and survival data were collected. Tissue microarrays were created and stained to determine the mismatch repair (MMR) protein status of each tumour. Local lymphocytic response to the tumour was assessed and graded.

Results:

About 358 patients were eligible. Of these 88 had an NLR ⩾5, which predicted lower overall survival and greater disease recurrence. A high NLR is associated with higher pT- and pN-stage and a greater incidence of extramural venous invasion. MMR protein status was not associated with NLR. A pronounced lymphocytic reaction at the invasive margin (IM) indicated a better prognosis and was associated with a lower NLR.

Conclusion:

Neutrophil-to-lymphocyte ratio predicts disease-free and overall survival and is associated with a more aggressive tumour phenotype. The lymphocytic response to tumour at the IM is associated with NLR however dMMR is not. Neutrophil-to-lymphocyte ratio is a cheap, easy-to-access test that predicts outcome in CRC.

Corneal endothelial specular microscopy following deep lamellar keratoplasty with lyophilised tissue

PURPOSE

To assess the corneal endothelial cell density following deep lamellar keratoplasty (DLK) carried out by air dissection and with the transplantation of lyophilised tissue.

METHOD

Contact endothelial specular microscopy was carried out on a series of patients who had undergone DLK with a minimum of 1 year post-operative follow-up.

RESULTS

Twenty eyes of 18 patients were examined at follow-up times ranging from 1 to 8 years post-operatively (mean 3 years). Indications for surgery were: keratoconus (n = 12), herpes simplex virus (HSV) keratitis (n = 1), herpes zoster ophthalmicus (HZO) keratitis (n = 1), lipid keratopathy (n = 2), lattice dystrophy (n = 1) and corneal scarring (n = 3). Overall, mean post-operative cell density was 2417 cells/mm2 (range 928-3656 cells/mm2). In eyes with pathological conditions not likely to have affected the endothelial cell density, such as keratoconus or lattice degeneration, the mean cell density was 2837 cells/mm2 (range 1030-3656 cells/mm2).

CONCLUSIONS

In patients undergoing DLK for conditions such as keratoconus the post-operative cell density was at a normal level in the majority of cases. Cell loss through this surgical intervention thus appears generally to be small. The prospect for long-term survival of these grafts is good.

Palliative biliary stents for obstructing pancreatic carcinoma

BACKGROUND

Palliative endoscopic stents or surgical by-pass are often required for inoperable pancreatic carcinoma to relieve symptomatic obstruction of the distal biliary tree. The optimal method of intervention remains unknown.

OBJECTIVES

To compare surgery, metal endoscopic stents and plastic endoscopic stents in the relief of distal biliary obstruction in patients with inoperable pancreatic carcinoma.

SEARCH STRATEGY

We searched the databases of the Cochrane Upper Gastrointestinal and Pancreatic Group specialised register, Cochrane Central Register of Controlled Trials , MEDLINE, EMBASE, CancerLit, Current Concepts Database and BIDS (September 2002 to September 2004). Reference lists of articles and published abstracts from UEGW and DDW were hand-searched.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing surgery to endoscopic stenting, endoscopic metal stents to plastic stents, and different types of endoscopic plastic and metal stents, used to relieve obstruction of the distal bile duct in patients with inoperable pancreatic carcinoma.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality and extracted data. Adverse effects information was collected from the trials.

MAIN RESULTS

Twenty-one trials involving 1,454 people were included. Based on meta-analysis, endoscopic stenting with plastic stents appears to be associated with a reduced risk of complications (RR 0.60, 95% CI 0.45 - 0.81), but with higher risk of recurrent biliary obstruction prior to death (RR 18.59, 95% CI 5.33 - 64.86) when compared with surgery. There was a trend towards higher 30-day mortality in the surgical group (p=0.07, RR 0.58, 95% CI 0.32, 1.04). There was no evidence of a difference in technical or therapeutic success. Other outcomes were not suitable for meta-analysis. No trials comparing endoscopic metal stents to surgery were identified. In endoscopic stent comparisons, metal biliary stents appear to have a lower risk of recurrent biliary obstruction than plastic stents (RR 0.52, 95% CI 0.39 - 0.69). There was no significant statistical difference in technical success, therapeutic success, complications or 30-day mortality using meta-analysis. A narrative review of studies of the cost-effectiveness of metal stents drew conflicting conclusions, but results may be dependent on the patients' length of survival. Neither Teflon, hydrourethane, or hydrophilic coating appear to improve the patency of plastic stents above polyethylene in the trials reviewed. Only perflouro alkoxy plastic stents had superior outcome to polyethylene stents in one trial. The single eligible trial comparing types of metal stents reported higher patency with covered stents, but also a higher risk of complications. These results are based on review of the trials individual results only.

AUTHORS' CONCLUSIONS

Endoscopic metal stents are the intervention of choice at present in patients with malignant distal obstructive jaundice due to pancreatic carcinoma. In patients with short predicted survival, their patency benefits over plastic stents may not be realised. Further RCTs are needed to determine the optimal stent type for these patients.

Three-dimensional structure of the photosystem II core dimer of higher plants determined by electron microscopy

Here we report the first three-dimensional structure of a higher plant photosystem II core dimer determined by electron crystallography at a resolution sufficient to assign the organization of its transmembrane helices. The locations of 34 transmembrane helices in each half of the dimer have been deduced, 22 of which are assigned to the major subunits D1 (5), D2 (5), CP47 (6), and CP43 (6). CP47 and CP43, located on opposite sides of the D1/D2 heterodimer, are structurally similar to each other, consisting of 3 pairs of transmembrane helices arranged in a ring. Both CP47 and CP43 have densities protruding from the lumenal surface, which are assigned to the loops joining helices 5 and 6 of each protein. The remaining 12 helices within each half of the dimer are attributed to low-molecular-weight proteins having single transmembrane helices. Comparison of the subunit organization of the higher plant photosystem II core dimer reported here with that of its thermophilic cyanobacterial counterpart recently determined by X-ray crystallography shows significant similarities, indicative of a common evolutionary origin. Some differences are, however, observed, and these may relate to variations between the two classes of organisms in antenna linkage or thermostability.

Distinctive patterns of memory function in subgroups of females with Turner syndrome: evidence for imprinted loci on the X-chromosome affecting neurodevelopment

X-monosomy is a form of Turner syndrome (TS) in which an entire X chromosome is missing. It is usually assumed that neuropsychological deficits in females with TS result from insufficient dosage of gene products from alleles on the sex chromosomes. If so, then parental origin of the single X chromosome should be immaterial. However, if there are imprinted genes on the X chromosome affecting brain development, neuropsychological development will depend on the parental origin of the single X chromosome. We contrasted verbal and visuospatial memory in females with a single paternal X chromosome (45,X(p)) and those with a single maternal X (45,X(m)). Neither group showed any impairment on immediate story recall; if anything, performance was above control levels. Groups did not differ on a measure of delayed recall. However, when delayed recall was considered after adjusting for level of immediate recall, 45,X(m) females showed enhanced verbal forgetting relative to controls over a delay. On the Rey figure, both groups were poor at copying the figure, but, after adjusting scores for initial copy score and strategy, only the 45,X(p) females showed disproportionate forgetting relative to controls. We propose there may be one or more imprinted genes on the X chromosome that affect the development of lateralised brain regions important for memory function.

Clinical pharmacology and economics of recombinant human erythropoietin in end-stage renal disease: the case for subcutaneous administration

The clinical pharmacology of human recombinant erythropoietin (epoetin) was studied in order to compare the effectiveness of various routes and dosing schedules in dialysis patients. Thirty-six patients received epoetin beta three times a week i.v. for at least 12 wk. The mean dose needed to achieve target hemoglobin was 225 +/- 36 U/kg per week (median dose, 180 U/kg per week). Twenty-eight of 36 patients who were converted to a once-a-week i.v. schedule increased their requirements to 429 +/- 50 U/kg per week in order to maintain a target hematocrit of 33 to 40 vol%. Twelve of 28 patients could maintain their target hematocrit when dosed once a week s.c. at 84 +/- 10 U/kg. The other 16 patients required 137 +/- 15 U/kg per week divided into two doses. In the entire group of 28 patients, the weekly requirement for epoetin was reduced by 50% when the s.c. route was used two or three times a week. Pharmacokinetic studies performed during chronic therapy indicated rapid clearance of erythropoietin (t1/2 of 6.8 +/- 0.3 h). Single i.v. doses greater than 150 U/kg were required to increase basal erythropoietin by 30 mU/mL at 44 h postdosing. With s.c. dosing, such increments in erythropoietin levels frequently persisted beyond 60 h because of prolonged and slow absorption. Pharmacokinetic simulations in conjunction with clinical correlation of the erythropoietic response suggest that the duration that the erythropoietin levels are maintained, and not the absolute peaks, is the primary determinant of efficacy. This may result from nonlinearity in the dose response. Pharmacokinetic simulation also indicated that i.v. dosing could not maintain adequate interdialytic erythropoietin levels, whereas s.c. dosing could. Cost analysis indicated that the use of s.c. dosing two or three times a week at an average total weekly dose of 110 to 120 U/kg is effective treatment of anemia in most dialysis patients.

The impact of the Calman-Hine report on the processes and outcomes of care for Yorkshire's colorectal cancer patients

The 1995 Calman-Hine plan outlined radical reform of the UK's cancer services with the aim of improving outcomes and reducing inequalities in NHS cancer care. Its main recommendation was to concentrate care into the hands of site-specialist, multi-disciplinary teams. This study aimed to determine if the implementation of Calman-Hine cancer teams was associated with improved processes and outcomes of care for colorectal cancer patients. The design included longitudinal survey of 13 colorectal cancer teams in Yorkshire and retrospective study of population-based data collected by the Northern and Yorkshire Cancer Registry and Information Service. The population was all colorectal cancer patients diagnosed and treated in Yorkshire between 1995 and 2000. The main outcome measures were: variations in the use of anterior resection and preoperative radiotherapy in rectal cancer, chemotherapy in Dukes stage C and D patients, and five-year survival. Using multilevel models, these outcomes were assessed in relation to measures of the extent of Calman-Hine implementation throughout the study period, namely: (i) each team's degree of adherence to the Manual of Cancer Service Standards (which outlines the specification of the 'ideal' colorectal cancer team) and (ii) the extent of site specialisation of each team's surgeons. Variation was observed in the extent to which the colorectal cancer teams in Yorkshire had conformed to the Calman-Hine recommendations. An increase in surgical site specialisation was associated with increased use of preoperative radiotherapy (OR=1.43, 95% CI=1.04-1.98, P<0.04) and anterior resection (OR=1.43, 95% CI=1.16-1.76, P<0.01) in rectal cancer patients. Increases in adherence to the Manual of Cancer Service Standards was associated with improved five-year survival after adjustment for the casemix factors of age, stage of disease, socioeconomic status and year of diagnosis, especially for colon cancer (HR=0.97, 95% CI=0.94-0.99 P<0.01). There was a similar trend of improved survival in relation to increased surgical site specialisation for rectal cancer, although the effect was not statistically significant (HR=0.93, 95% CI=0.84-1.03, P=0.15). In conclusion, the extent of implementation of the Calman-Hine report has been variable and its recommendations are associated with improvements in processes and outcomes of care for colorectal cancer patients.

Subunit positioning and transmembrane helix organisation in the core dimer of photosystem II

Recently 3D structural models of the photosystem II (PSII) core dimer complexes of higher plants (spinach) and cyanobacteria (Synechococcus elongatus) have been derived by electron [Rhee et al. (1998) Nature 396, 283-286; Hankamer et al. (2001) J. Struct. Biol., in press] and X-ray [Zouni et al. (2001) Nature 409, 739-743] crystallography respectively. The intermediate resolutions of these structures do not allow direct identification of side chains and therefore many of the individual subunits within the structure are unassigned. Here we review the structure of the higher plant PSII core dimer and provide evidence for the tentative assignment of the low molecular weight subunits. In so doing we highlight the similarities and differences between the higher plant and cyanobacterial structures.

Ifosfamide, carboplatin and etoposide in children with poor-risk relapsed Wilms' tumor: a Children's Cancer Group report

BACKGROUND

The outcome of children with relapsed Wilms' tumor is poor, especially with poor-risk factors such as unfavorable histology, early recurrence, previous three-drug therapy, relapse not confined to lungs and abdominal relapse following abdominal radiotherapy. We report the overall response rate, progression-free survival and overall survival of 11 children with relapsed and poor-risk Wilms' tumor following ifosfamide/carboplatin/etoposide (ICE) chemotherapy.

PATIENTS AND METHODS

ICE therapy consisted of ifosfamide 1800 mg/m2/day (on day 0-4), carboplatin 400 mg/m2/day (on day 0-1) and etoposide 100 mg/m2/day (on day 0-4). The median age at diagnosis was 39 months (range from 13 months to 16 years) and the median time to relapse after initial diagnosis was 9 months (range 4-72 months). All but one patient had at least one poor prognostic feature, with eight patients showing three or four.

RESULTS

After ICE chemotherapy the number of patients showing a complete response (CR) was three (27%) and a partial response (PR) was six (55%). The overall response rate (CR+PR) was 82%. Five of the six patients with a PR subsequently achieved a CR with further therapy. The 3-year event-free survival and overall survival were 63.6 +/- 14.5%.

CONCLUSIONS

The response rate in children with relapsed and poor-risk Wilms' tumor is >80% with ICE re-induction chemotherapy followed by post-ICE therapy. The optimal approach for post-ICE consolidation therapy has yet to be determined.

Attention and regional cerebral blood flow in posttraumatic stress disorder patients with substance abuse histories

Performance on an attentional task was assessed in posttraumatic stress disorder patients with substance abuse histories (PTSD-SA). Positron emission tomography (PET) was used to measure concurrent regional cerebral blood flow (rCBF). Eight male PTSD-SA patients and eight normal subjects each received three serial PET scans with 15O-labeled water under the following conditions: (1) resting, (2) auditory continuous performance task (ACPT1), and (3) repeat auditory task (ACPT2). PTSD-SA patients made more errors of commission on the ACPT than normal subjects. Examination of right frontal and parietal cortex ACPT task substrates revealed decreased parietal blood flow in PTSD-SA, which may represent a pathophysiology for poor attentional task performance in PTSD-SA. Attentional problems may underlie other symptomatology in PTSD.

Reduced intensity allogeneic umbilical cord blood transplantation in children and adolescent recipients with malignant and non-malignant diseases

There is a significant amount of morbidity and mortality following myeloablative umbilical cord blood transplantation (UCBT). Reduced intensity (RI) conditioning offers an alternative to myeloablative conditioning before UCBT. We investigated RI-UCBT in 21 children and adolescents with malignant (n=14), and non-malignant diseases (n=7). RI conditioning consisted of fludarabine (150-180 mg/m2) with either busulfan (< or = 8 mg/kg)+rabbit antithymocyte globulin (R-ATG; n=16) or cyclophosphamide+R-ATG+/-etoposide (n=5). Human leukocyte antigen match: 4/6 (n=13), 5/6 (n=5) and 6/6 (n=3). The median total nucleated cell and CD34+ cell dose per kilogram were 3.58 x 10(7) and 2.54 x 10(5), respectively. The median time for neutrophil and platelet engraftment was 17.5 and 52 days, respectively. There were six primary graft failures (chronic myelogenous leukemia (CML), beta-thalassemia, hemophagocytic lymphohistiocytosis (HLH) and myelodysplastic syndrome (MDS)). The probability of developing grade II to grade IV acute graft-versus-host disease (GVHD) and chronic GVHD was 28.6 and 16.7%, respectively. Incidence of transplant-related mortality (TRM) was 14%. The 5 years overall survival (OS) in all patients was 59.8%. The 5 years OS for patients with average versus poor-risk malignancy was 77.8 versus 22.2% (P=0.03). RI-UCBT may result in graft failure in specific high-risk chemo-naïve patients (CML, beta-thalassemia, HLH and MDS), but in more heavily pretreated pediatric and adolescent recipients results in rapid engraftment and may be associated with decreased severe GVHD and TRM.