Enhanced Chromium (VI) Adsorption onto Waste Pomegranate-Peel-Derived Biochar for Wastewater Treatment: Performance and Mechanism.

Surface chemical modification allows for the rational construction of biochar with desirable structures and functionalities for environment purification. Fruit-peel-derived adsorbing material has been well studied in the adsorption of heavy-metal removal due to its abundance and non-toxicity, but its precise mechanism in removing chromium-containing pollutants remains unclear. Herein, we explored the potential application of engineered biochar prepared from fruit waste via chemical modification to remove chromium (Cr) from an aqueous solution. By synthesizing two types of agricultural residue-derived adsorbents, including pomegranate peel adsorbent (PG) and its modified product, pomegranate-peel-derived biochar (PG-B), via chemical and thermal decomposition methods, we elucidated the adsorption property of Cr(VI) on the studied materials and identified the cation retention mechanism of the adsorption process. Batch experiments and varied characterizations demonstrated that superior activity was exhibited in PG-B, which can contribute to the porous surfaces caused by pyrolysis and effective active sites resulting from alkalization. The highest Cr(VI) adsorption capacity is obtained at pH 4, a dosage of 6.25 g L-1, and a contact time of 30 min. The maximum adsorption efficiency of 90.50% in a short period (30 min) was obtained on PG-B, while PG reached a removal performance of 78.01% at 60 min. The results from kinetic and isotherm models suggested that monolayer chemisorption dominated the adsorption process. The Langmuir maximum adsorption capacity is 16.23 mg g-1. This study shortened the adsorption equilibrium time of pomegranate-based biosorbents and presents positive significance in designing and optimizing waste fruit-peel-derived adsorption materials for water purification.

Mutation of DEFECTIVE EMBRYO SAC1 results in a low seed-setting rate in rice by regulating embryo sac development.

The seed-setting rate has a significant effect on grain yield in rice (Oryza sativa L.). Embryo sac development is essential for seed setting; however, the molecular mechanism underlying this process remains unclear. Here, we isolated defective embryo sac1 (des1), a rice mutant with a low seed-setting rate. Cytological examination showed degenerated embryo sacs and reduced fertilization capacity in des1. Map-based cloning revealed a nonsense mutation in OsDES1, a gene that encodes a putative nuclear envelope membrane protein (NEMP)-domain-containing protein that is preferentially expressed in pistils. The OsDES1 mutation disrupts the normal formation of functional megaspores, which ultimately results in a degenerated embryo sac in des1. Reciprocal crosses showed that fertilization is abnormal and that the female reproductive organ is defective in des1. OsDES1 interacts with LONELY GUY (LOG), a cytokinin-activating enzyme that acts in the final step of cytokinin synthesis; mutation of LOG led to defective female reproductive organ development. These results demonstrate that OsDES1 functions in determining the rice seed-setting rate by regulating embryo sac development and fertilization. Our study sheds light on the function of NEMP-type proteins in rice reproductive development.

Neutrophil-to-Lymphocyte Ratio and Ferritin as Measurable Tools for Disease Burden and B Symptoms in Pediatric Patients With Hodgkin Lymphoma.

BACKGROUND: Pediatric Hodgkin lymphoma (HL) has been treated successfully with risk-adapted and response-adapted therapy. While risk factors like Ann Arbor staging system, B symptoms, bulky disease, and erythrocyte sedimentation rate were measured objectively, B symptoms are subjective tools. We evaluated whether the neutrophil-to-lymphocyte ratio (NLR) and inflammatory marker levels correlated with B symptoms and disease burden. MATERIALS AND METHODS: We conducted a retrospective chart review of all children ≤14 years old with pathology-confirmed HL treated at our institution. Data included clinical and pathologic features, pretreatment erythrocyte sedimentation rate, ferritin levels; monocyte, neutrophil, and lymphocyte counts; and NLR. Optimum cutoffs of variables significantly associated with B symptoms were determined based on receiver operating characteristic curves. RESULTS: Sixty-four patients were included in the analysis. Sixteen patients (25%) had B symptoms. Patients with B symptoms had higher ferritin levels (P<0.0001), monocyte counts (P=0.0060), neutrophil counts (P=0.0003) and NLR (P<0.0001), and lower lymphocyte counts (P=0.0017). Multiple receiver operating characteristic curves were generated to identify the optimum cutoff. Sensitivities and specificities of NLR (cutoff, 3.5) and ferritin (cutoff, 173 ng/mL) were the highest (81.25% and 81.25% [P<0.0001] and 89.36% and 75% [P<0.0001], respectively). Patients with NLR >3.5 and ferritin >173 (ng/mL) had significantly higher stage, bulky disease, and B symptoms. NLR and ferritin are not predictive of worst outcome in the cohort analyzed. CONCLUSIONS: NLR and ferritin levels were associated with high disease burden and B symptoms. Therefore, these variables can be used as measurable tools for B symptoms that can help stratify patients with HL. Larger and prospective studies are needed to validate these findings.

DCET1 Controls Male Sterility Through Callose Regulation, Exine Formation, and Tapetal Programmed Cell Death in Rice.

In angiosperms, anther development comprises of various complex and interrelated biological processes, critically needed for pollen viability. The transitory callose layer serves to separate the meiocytes. It helps in primexine formation, while the timely degradation of tapetal cells is essential for the timely callose wall dissolution and pollen wall formation by providing nutrients for pollen growth. In rice, many genes have been reported and functionally characterized that are involved in callose regulation and pollen wall patterning, including timely programmed cell death (PCD) of the tapetum, but the mechanism of pollen development largely remains ambiguous. We identified and functionally characterized a rice mutant dcet1, having a complete male-sterile phenotype caused by defects in anther callose wall, exine patterning, and tapetal PCD. DCET1 belongs to the RNA recognition motif (RRM)-containing family also called as the ribonucleoprotein (RNP) domain or RNA-binding domain (RBD) protein, having single-nucleotide polymorphism (SNP) substitution from G (threonine-192) to A (isoleucine-192) located at the fifth exon of LOC_Os08g02330, was responsible for the male sterile phenotype in mutant dcet1. Our cytological analysis suggested that DCET1 regulates callose biosynthesis and degradation, pollen exine formation by affecting exine wall patterning, including abnormal nexine, collapsed bacula, and irregular tectum, and timely PCD by delaying the tapetal cell degeneration. As a result, the microspore of dcet1 was swollen and abnormally bursted and even collapsed within the anther locule characterizing complete male sterility. GUS and qRT-PCR analysis indicated that DCET1 is specifically expressed in the anther till the developmental stage 9, consistent with the observed phenotype. The characterization of DCET1 in callose regulation, pollen wall patterning, and tapetal cell PCD strengthens our knowledge for knowing the regulatory pathways involved in rice male reproductive development and has future prospects in hybrid rice breeding.

Exploiting Genic Male Sterility in Rice: From Molecular Dissection to Breeding Applications.

Rice (Oryza sativa L.) occupies a very salient and indispensable status among cereal crops, as its vast production is used to feed nearly half of the world's population. Male sterile plants are the fundamental breeding materials needed for specific propagation in order to meet the elevated current food demands. The development of the rice varieties with desired traits has become the ultimate need of the time. Genic male sterility is a predominant system that is vastly deployed and exploited for crop improvement. Hence, the identification of new genetic elements and the cognizance of the underlying regulatory networks affecting male sterility in rice are crucial to harness heterosis and ensure global food security. Over the years, a variety of genomics studies have uncovered numerous mechanisms regulating male sterility in rice, which provided a deeper and wider understanding on the complex molecular basis of anther and pollen development. The recent advances in genomics and the emergence of multiple biotechnological methods have revolutionized the field of rice breeding. In this review, we have briefly documented the recent evolution, exploration, and exploitation of genic male sterility to the improvement of rice crop production. Furthermore, this review describes future perspectives with focus on state-of-the-art developments in the engineering of male sterility to overcome issues associated with male sterility-mediated rice breeding to address the current challenges. Finally, we provide our perspectives on diversified studies regarding the identification and characterization of genic male sterility genes, the development of new biotechnology-based male sterility systems, and their integrated applications for hybrid rice breeding.

The MYB transcription factor Baymax1 plays a critical role in rice male fertility.

Key message Rice male fertility gene Baymax1, isolated through map-based cloning, encodes a MYB transcription factor and is essential for rice tapetum and microspore development.Abstract The mining and characterization of male fertility gene will provide theoretical and material basis for future rice production. In Arabidopsis, the development of male organ (namely anther), usually involves the coordination between MYB (v-myb avian myeloblastosis viral oncogene homolog) and bHLH (basic helix-loop-helix) members. However, the role of MYB proteins in rice anther development remains poorly understood. In this study, we isolated and characterized a male sterile mutant (with normal vegetative growth) of Baymax1 (BM1), which encodes a MYB protein. The bm1 mutant exhibited slightly lagging meiosis, aborted transition of the tapetum to a secretory type, premature tapetal degeneration, and abnormal pollen exine formation, leading to ultimately lacks of visible pollens in the mature white anthers. Map-based cloning, complementation and targeted mutagenesis using CRISPR/Cas9 technology demonstrated that the mutated LOC_Os04g39470 is the causal gene in bm1. BM1 is preferentially expressed in rice anthers from stage 5 to stage 10. Phylogenetic analysis indicated that rice BM1 and its homologs in millet, maize, rape, cabbage, and pigeonpea are evolutionarily conserved. BM1 can physically interacts with bHLH protein TIP2, EAT1, and PHD (plant homeodomain)-finger member TIP3, respectively. Moreover, BM1 affects the expression of several known genes related to tapetum and microspore development. Collectively, our results suggest that BM1 is one of key regulators for rice male fertility and may serve as a potential target for rice male-sterile line breeding and hybrid seed production.

Cytomegalovirus viremia among pediatric oncology non-stem cell transplant patients with prolonged fever neutropenia.

BACKGROUND: Cytomegalovirus (CMV) is a rare cause of prolonged febrile neutropenia (PFN) among pediatric oncology patients, especially in non-stem cell transplant setting (Non-SCTS). Infectious Diseases Society of America (IDSA) guidelines stated briefly that neutropenia is not considered as an indication of CMV re-activation, and thus preventive strategies are not needed; however, multiple studies pressed on the need to treat CMV viremia among patients with PFN even when there is no evidence of end-organ involvement. Therefore, this study aimed to prospectively investigate the significance of CMV as a cause of PFN among pediatric oncology patients in a Non-SCTS. PATIENTS AND METHODS: This was a prospective cohort study that was done at Princess Norah Oncology Center, King Abdulaziz Medical City in Jeddah, Saudi Arabia. CMV viral load was monitored weekly once the subject was identified as a case of PFN until resolution. Subjects and treating physicians were blinded to CMV viral load results. RESULTS: The data of 27 PFN episodes (48% males) were analyzed. The incidence of CMV viremia was reported as 29.6%. Both CMV positive and negative episodes of PFN had similar rate of spontaneous resolution (p=0.669), with overall mortality as 105 and 125 per 1000 PFN episodes, respectively. No subject received anti-CMV in the positive CMV group; however, one subject did in the negative group for reasons other than CMV infection. CONCLUSION: This study demonstrated that CMV was not a significant cause of PFN in Non-SCTS. CMV also had no significant role in terms of survival and severity of the PFN episode.

A proteomic approach identifies novel proteins and metabolites for lesion mimic formation and disease resistance enhancement in rice.

Lesion mimic mutants are ideal genetic materials to study programmed cell death and defense signaling in plants. However, the molecular basis of lesion mimic formation remains largely unknown. Here, we first used a proteomic approach to identify differentially expressed proteins during dynamic lesion mimic formation in the rice oscul3a mutant, then electron microscope observation and physiological assays were used to analyze the mutant. The oscul3a mutant had disrupted cell metabolism balance, and the identified differentially expressed proteins were mainly located in the chloroplast and cytoplasm, which caused enhanced lipid metabolism, but suppressed carbon/nitrogen metabolism with reduced growth and grain quality. The oscul3a mutant had higher salicylic acid (SA) concentration in leaves, and H2O2 was shown to accumulate late in the formation of lesions. The secondary metabolite coumarin induced reactive oxygen species (ROS) and had rice blast resistance activity. Moreover, the cell death initiated lesion mimic formation of oscul3a mutant was light-sensitive, which might be associated with metabolite biosynthesis and accumulation. This study sheds light on the metabolic transition associated with cell death and defense response, which is under tight regulation by OsCUL3a and metabolism-related proteins, and the newly identified chemicals in the secondary metabolic pathway can potentially be used to control disease in crop plants.

Improving Lodging Resistance: Using Wheat and Rice as Classical Examples.

One of the most chronic constraints to crop production is the grain yield reduction near the crop harvest stage by lodging worldwide. This is more prevalent in cereal crops, particularly in wheat and rice. Major factors associated with lodging involve morphological and anatomical traits along with the chemical composition of the stem. These traits have built up the remarkable relationship in wheat and rice genotypes either prone to lodging or displaying lodging resistance. In this review, we have made a comparison of our conceptual perceptions with foregoing published reports and proposed the fundamental controlling techniques that could be practiced to control the devastating effects of lodging stress. The management of lodging stress is, however, reliant on chemical, agronomical, and genetic factors that are reducing the risk of lodging threat in wheat and rice. But, still, there are many questions remain to be answered to elucidate the complex lodging phenomenon, so agronomists, breeders, physiologists, and molecular biologists require further investigation to address this challenging problem.

LSSR1 facilitates seed setting rate by promoting fertilization in rice.

Seed setting rate is one of the major components that determine rice (Oryza sativa L.) yield. Successful fertilization is necessary for normal seed setting. However, little is known about the molecular mechanisms governing this process. In this study, we report a novel rice gene, LOW SEED SETTING RATE1 (LSSR1), which regulates the seed setting rate by facilitating rice fertilization. LSSR1 encodes a putative GH5 cellulase, which is highly conserved in plants. LSSR1 is predominantly expressed in anthers during the microsporogenesis stage, and its encoded protein contains a signal peptide at the N-terminal, which may be a secretory protein that stores in pollen grains and functions during rice fertilization. To explore the physiological function of LSSR1 in rice, loss-of-function mutants of LSSR1 were created through the CRISPR-Cas9 system, which showed a significant decrease in rice seed setting rate. However, the morphology of the vegetative and reproductive organs appears normal in lssr1 mutant lines. In addition, lssr1 pollen grains could be normally stained by I2-KI solution. Cytological results demonstrate that the blockage of fertilization mostly accounted for the low seed setting rate in lssr1 mutant lines, which was most likely caused by abnormal pollen grain germination, failed pollen tube penetration, and retarded pollen tube elongation. Together, our results suggest that LSSR1 plays an important role in rice fertilization, which in turn is vital for maintaining rice seed setting rate.

TDR INTERACTING PROTEIN 3, encoding a PHD-finger transcription factor, regulates Ubisch bodies and pollen wall formation in rice.

Male reproductive development involves a complex series of biological events and precise transcriptional regulation is essential for this biological process in flowering plants. Several transcriptional factors have been reported to regulate tapetum and pollen development, however the transcriptional mechanism underlying Ubisch bodies and pollen wall formation remains less understood. Here, we characterized and isolated a male sterility mutant of TDR INTERACTING PROTEIN 3 (TIP3) in rice. The tip3 mutant displayed smaller and pale yellow anthers without mature pollen grains, abnormal Ubisch body morphology, no pollen wall formation, as well as delayed tapetum degeneration. Map-based cloning demonstrated that TIP3 encodes a conserved PHD-finger protein and further study confirmed that TIP3 functioned as a transcription factor with transcriptional activation activity. TIP3 is preferentially expressed in the tapetum and microspores during anther development. Moreover, TIP3 can physically interact with TDR, which is a key component of the transcriptional cascade in regulating tapetum development and pollen wall formation. Furthermore, disruption of TIP3 changed the expression of several genes involved in tapetum development and degradation, biosynthesis and transport of lipid monomers of sporopollenin in tip3 mutant. Taken together, our results revealed an unprecedented role for TIP3 in regulating Ubisch bodies and pollen exine formation, and presents a potential tool to manipulate male fertility for hybrid rice breeding.

OsMS1 functions as a transcriptional activator to regulate programmed tapetum development and pollen exine formation in rice.

KEY MESSAGE: OsMS1 functions as a transcriptional activator and interacts with known tapetal regulatory factors through its plant homeodomain (PHD) regulating tapetal programmed cell death (PCD) and pollen exine formation in rice. The tapetum, a hallmark tissue in the stamen, undergoes degradation triggered by PCD during post-meiotic anther development. This degradation process is indispensable for anther cuticle and pollen exine formation. Previous study has shown that PTC1 plays a critical role in the regulation of tapetal PCD. However, it remained unclear how this occurs. To further investigate the role of this gene in rice, we used CRISPR/Cas9 system to generate the homozygous mutant named as osms1, which showed complete male sterility with slightly yellow and small anthers, as well as invisible pollen grains. In addition, cytological observation revealed delayed tapetal PCD, defective pollen exine formation and a lack of DNA fragmentation according to a TUNEL analysis in the anthers of osms1 mutant. OsMS1, which encodes a PHD finger protein, was located in the nucleus of rice protoplasts and functioned as a transcription factor with transcriptional activation activity. Y2H and BiFC assays demonstrated that OsMS1 can interact with OsMADS15 and TDR INTERACTING PROTEIN2 (TIP2). It has been reported that TIP2 coordinated with TDR to modulate the expression of EAT1 and further regulated tapetal PCD in rice. Results of qPCR suggested that the expression of the genes associated with tapetal PCD and pollen wall biosynthesis, such as EAT1, AP37, AP25, OsC6 and OsC4, were significantly reduced in osms1 mutant. Taken together, our results demonstrate that the interaction of OsMS1 with known tapetal regulatory factors through its PHD finger regulates tapetal PCD and pollen exine formation in rice.

OsGPAT3 Plays a Critical Role in Anther Wall Programmed Cell Death and Pollen Development in Rice.

In flowering plants, ideal male reproductive development requires the systematic coordination of various processes, in which timely differentiation and degradation of the anther wall, especially the tapetum, is essential for both pollen formation and anther dehiscence. Here, we show that OsGPAT3, a conserved glycerol-3-phosphate acyltransferase gene, plays a critical role in regulating anther wall degradation and pollen exine formation. The gpat3-2 mutant had defective synthesis of Ubisch bodies, delayed programmed cell death (PCD) of the inner three anther layers, and abnormal degradation of micropores/pollen grains, resulting in failure of pollen maturation and complete male sterility. Complementation and clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated 9 (Cas9) experiments demonstrated that OsGPAT3 is responsible for the male sterility phenotype. Furthermore, the expression level of tapetal PCD-related and nutrient metabolism-related genes changed significantly in the gpat3-2 anthers. Based on these genetic and cytological analyses, OsGPAT3 is proposed to coordinate the differentiation and degradation of the anther wall and pollen grains in addition to regulating lipid biosynthesis. This study provides insights for understanding the function of GPATs in regulating rice male reproductive development, and also lays a theoretical basis for hybrid rice breeding.

The prognostic significance of hypertension at diagnosis in children with wilms tumor.

OBJECTIVES: To determine the prognostic effect of hypertension at diagnosis on outcomes of children with Wilms tumor (WT).   Methods: A single center retrospective analysis was conducted on 85 consecutive children with WT diagnosed between January 2000 and August 2013. Patients were classified as hypertensive or normotensive at diagnosis. Overall survival (OS) and progression-free survival (PFS) were estimated using the Kaplan-Meier method. Cox regression was used to determine the predictive significance of hypertension and other clinical factors.  Results: Seventy-one patients had complete data. Of this, 25 (35.2%) were hypertensive and 46 (64.8%) normotensive with corresponding remission rates of 56.0% versus 82.6%, p=0.032; and death as first event of 7% versus 0%, p=0.004. The 5-year OS in the hypertensive versus normotensive patients were (67.1±10.3% versus 89.6±4.9%, p=0.009) and the corresponding 5-year PFS were (53.4±10.4% versus 79.1±6.2%, p=0.007). With univariate analysis, hypertension and local stage were predictors of OS (p=0.012 and p=0.029) and PFS (p=0.030 and p=0.008). In the multivariate analysis, hypertension, local stage, and histopathology were identified as independent prognostic factors of OS (p=0.004, p=0.034, and p=0.038); and hypertension  and local stage as prognostic for PFS (p=0.010 and p=0.012).  Conclusion: Hypertension at diagnosis is a prognostic predictor of poor outcome in WT and may signify tumor resistance.

Extensive gingival and respiratory tract Kaposi sarcoma in a child after allogenic hematopoietic stem cell transplantation.

An 8-year-old, human immune virus-negative boy received full human leukocyte antigen-matched related allogenic hematopoietic stem cell transplantation (HSCT) for relapsed acute myeloid leukemia. While on cyclosporine A and prednisolone therapy for graft versus host disease, he developed extensive gingival, cutaneous, and respiratory tract human herpes virus-8-associated Kaposi sarcoma (KS). Withdrawal of cyclosporine, tapering of prednisolone, recovery of lymphocyte count, and local supportive measures resulted in resolution of his gingival and respiratory tract lesions. To our knowledge this is the first case of gingival and extensive respiratory tract KS to be reported in a child post HSCT.

Evaluation of therapeutic control in a Pakistani population with hypertension.

RATIONALE, AIMS AND OBJECTIVES: Cardiovascular diseases (CVD) are increasing at an alarming rate in South Asia. High blood pressure is a modifiable risk factor for CVD. In this study, we evaluated the control of blood pressure and the prevalence of cardiovascular risk factors in patients with hypertension. METHOD: A cross-sectional study was conducted in 50 primary health care centres throughout Pakistan. Individuals with a documented history of hypertension, receiving pharmacological therapy, were enrolled and evaluated for the control of their blood pressure. RESULTS: The recommended therapeutic control of hypertension (systolic blood pressure <140 mmHg, diastolic blood pressure <90 mmHg) was seen in only 6.4% of the study participants. Values of both the mean systolic and diastolic blood pressures in all subjects were higher than the desired therapeutic levels (P<0.001). There was a high prevalence in the study population of established but modifiable risk factors of CVD, such as smoking (30.5%), hypercholesterolemia (59.5%) and sedentary lifestyle (43.5%). Lack of therapeutic control of systolic blood pressure was found significantly associated with age, hypercholesterolemia and sedentary lifestyle (P<0.05). CONCLUSIONS: Patients being treated at primary health care centres in Pakistan have inadequate control of high blood pressure. Evidence-based continuous education of primary health care physicians is a necessary intervention for optimizing treatment strategies and achieving better therapeutic control of hypertension in our population.

Radiographic inguinal curl may indicate paraspinal misplacement of percutaneously inserted central venous catheters: report of three cases.

BACKGROUND: Misplacement of percutaneously inserted central venous catheters (PCVCs) into the paraspinal venous plexus can result in devastating outcomes. Several cases have been reported in the literature together with an explanation of the mechanism. OBJECTIVE: To describe three premature babies with their PCVCs inserted through the left saphenous vein that ended up in the lumbar spinal dural venous plexus. RESULTS: Plain radiographs obtained to check positions showed an unusual 360 degrees curl of the PCVC in the left inguinal area. CONCLUSION: We believe that misplacement of the catheter into the paraspinal venous plexus could be diagnosed with great accuracy if such a curl is seen.

A pilot study of prophylactic ciprofloxacin during delayed intensification in children with acute lymphoblastic leukemia.

BACKGROUND: We hypothesized that prophylactic administration of an appropriate antibiotic following each delayed intensification (DI) in children with acute lymphoblastic leukemia (ALL) would reduce the episodes of fever and bacteremia associated with neutropenia, and hence reduce both the rate and duration of hospitalization. PROCEDURE: All patients in the study were treated according to a modified Medical Research Council United Kingdom ALL XI (MRC UKALL XI) protocol utilizing three DI courses. Between June and December 2000 patients received prophylactic ciprofloxacin following DI courses. The rates of hospitalization and bacteremias were compared to ALL patients who had received between one and three DI courses prior to June 2000. RESULTS: There were 69 patients who received a total of 194 DIs (controls 130; study group 64). The rate of hospitalization was 90% in the controls and 58% in the study group (P < 0.001). The median hospital stay was 10.1 days for controls and 6.0 for the study group (P < 0.001). Intensive care unit admissions were reduced from 12 to 1.5% (P = 0.02). The overall rate of proven bacteremia was reduced from 22 to 9% (P = 0.028). There were no Gram-negative bacteremias in the study group compared to 10 (7.7%) in the controls (P < 0.001). CONCLUSIONS: Compared to historical controls, patients in this study receiving prophylactic ciprofloxacin had a reduced rate and duration of hospitalization and incidence of Gram-negative bacteremia.

Factors influencing central line infections in children with acute lymphoblastic leukemia: results of a single institutional study.

BACKGROUND: We compared the rates of infection in external catheters (ECs) and totally implantable devices (TIDs) and the effect of timing of insertion in children with acute lymphoblastic leukemia (ALL). PROCEDURE: Central line data was collected on all children with ALL referred to the National Guard Hospital, Jeddah. Data was collected retrospectively from 1996 to September 1999 and prospectively thereafter. Only ECs were inserted prior to 1999 subsequently TIDs were preferred. RESULTS: One hundred forty eight children with ALL, mean age 5.1 years had 129 ECs and 70 TIDs inserted for a total of 41,382 catheter days. The overall rate of infective episodes (infections/1,000 catheter days) was 3.43. Of the initial 148 lines 100 developed complications of which 76 (51%) were secondary to an infective episode. Only young age and treatment protocol were risk factors for first line infections (P < 0.05). There was weak evidence that ECs had an earlier time to infection compared to TIDs (P = 0.056). CONCLUSIONS: In this study, population central lines were associated with a high rate of infection. Treatment protocol and age were the only significant risk factors when only first lines were considered. Delaying catheter insertion for more than 3 weeks from diagnosis did not reduce the risk of infection.