Climate Change and Force Majeure on Childhood Oncology Services in a Low Resource Setting: Experience from a Tertiary Institution in Nigeria.

Childhood cancer patients are a vulnerable population who are adversely affected by any disaster that disrupts the healthcare ecosystem. The objective of this study was to describe the impact of flooding on access to care for childhood cancer patients in Bayelsa state, southern Nigeria. We review the effect of the 2022 flooding on childhood cancer care at the paediatric oncology unit of the Niger Delta University Teaching Hospital, southern Nigeria. The devastating floods caused closure of the health facility for four weeks. The challenges faced by the oncology patients included inability to access the facility due to destruction of roads and telecommunication networks, inaccessibility to chemotherapy drugs, postponement of surgeries, parental financial constraints due to income loss occasioned by the flood and worsened by inadequate health insurance. Two children, who were undergoing chemotherapy for rhabdomyosarcoma and retinoblastoma had their care transferred to an unaffected secondary care facility 24km away. Through teamwork and determination, the oncology team was able to overcome various obstacles to provide uninterrupted care for the patients and improve on future patient care during disasters. Care for childhood cancer patients should be prioritized by healthcare facilities especially in predictable flood prone areas like Bayelsa state. Emphasis should be on disaster preparedness training, development of outstations equipped with patient information, chemotherapy drugs and other requirements for continued care to prevent adverse childhood cancer care outcomes.Les patients atteints de cancer pédiatrique constituent une population vulnérable fortement touchée par toute catastrophe perturbant l'écosystème de soins de santé. L'objectif de cette étude était de décrire l'impact des inondations sur l'accès aux soins des patients atteints de cancer pédiatrique dans l'État de Bayelsa, dans le sud du Nigeria. Nous examinons l'effet des inondations de 2022 sur les soins du cancer pédiatrique à l'unité d'oncologie pédiatrique de l'Hôpital universitaire de la Niger Delta, dans le sud du Nigeria. Les inondations dévastatrices ont entraîné la fermeture de l'établissement de santé pendant quatre semaines. Les défis auxquels sont confrontés les patients en oncologie comprennent l'incapacité d'accéder aux installations en raison de la destruction des routes et des réseaux de télécommunication, l'inaccessibilité aux médicaments de chimiothérapie, le report des interventions chirurgicales, des contraintes financières parentales en raison de la perte de revenus causée par les inondations et aggravées par une assurance maladieinsuffisante. par le manque d'assurance maladie. Deux enfants, qui suivaient une chimiothérapie pour un rhabdomyosarcome et un rétinoblastome, ont vu leurssoinstransférésversunétablissementdesoinssecondairesnonaffecté à 24 km de là. Grâce au travail d'équipe et à la détermination, l'équipe d'oncologie a réussi à surmonter les différents obstacles pour assurer des soins ininterrompus aux patients et améliorer les soins futurs aux patients en cas de catastrophes. Les soins aux patients atteints de cancer pédiatrique devraient être une priorité pour les établissements de santé, en particulier dans les zones sujettes aux inondations prévisibles comme l'État de Bayelsa. L'accent devrait être mis sur la formation à la préparation aux catastrophes, le développement de postes extérieurs équipés d'informations sur les patients, de médicaments de chimiothérapie et d'autres éléments nécessaires pour assurer des soins continus, afin de prévenir des résultats défavorables dans les soins del'enfance atteinte de cancer. Mots-clés : Enfance, Cancer, Inondation, Force majeure.

Doctors' Knowledge, Comprehension, Attitude to and Application of Ethical Principles in Child Healthcare in a Nigerian Teaching Hospital.

BACKGROUND AND OBJECTIVES: Due to the prevailing socio-cultural and religious affiliations, Paediatricians in sub-Saharan Africa face unique ethical dilemmas. An understanding and application of the ethical principles can help prevent and resolve these dilemmas, and improve child health indices. The objective is to determine the knowledge, attitude and practical applications of non-maleficence and beneficence by child-care doctors at a Teaching Hospital. METHODS: This is a questionnaire-based study. Socio-demographics, knowledge and attitude towards the ethical principles, and its utilisation by doctors in childcare was sought. Data were analyzed using descriptive statistics. RESULTS: 294 doctors participated. The mean percentage knowledge score of nonmaleficence and beneficence was 31.00±21.14, significantly higher among doctors in Paediatrics (39.35±23.44, p=0.0001). For every decrease in professional rank, knowledge score decreased by 3.8224 (95% CI -5.824 - -1.819; p=0.0001). The doctors had a high mean percentage score on attitude towards ethics of 74.79±16.34, and for every increase in years of practice, attitude towards ethics score would increase by 2.922 (95% CI 1.133 to 4.711, p=0.001). There was a low practice score of 34.27±20.07. Majority (69%) encountered less than one dilemma a month. More than 90% of doctors had encountered dilemmas involving the principle of non-maleficence [184 (90.6%)], while 154 (75.9%) involved beneficence. CONCLUSION: Most respondents have a low level of knowledge and practice of the principles of nonmaleficence and beneficence. Their excellent attitude implies their willingness at improving their knowledge and practice.

Citric acid production by Aspergillus niger ATCC 9142 from a treated ethanol fermentation co-product using solid-state fermentation.

AIMS: To investigate the ability of the citric acid-producing strain Aspergillus niger ATCC 9142 to utilize the ethanol fermentation co-product corn distillers dried grains with solubles for citric acid production following various treatments. METHODS AND RESULTS: The ability of A. niger ATCC 9142 to produce citric acid and biomass on the grains was examined using an enzyme assay and a gravimetric method, respectively. Fungal citric acid production after 240 h was higher on untreated grains than on autoclaved grains or acid-hydrolysed grains. Fungal biomass production was enhanced after autoclaving and acid-hydrolysis of the grains. Phosphate supplementation to the grains slightly stimulated citric acid production while methanol addition decreased its synthesis. Using the phosphate-supplemented grains, the optimal incubation temperature, initial moisture content of the grains and the length of fermentation time for ATCC 9142 citric acid production were determined to be 25 degrees C, 82% and 240 h, respectively. CONCLUSIONS: A. niger ATCC 9142 synthesized citric acid on corn distillers dried grains with solubles. The phosphate-treated grains increased citric acid production by the strain. SIGNIFICANCE AND IMPACT OF THE STUDY: The ethanol fermentation co-product corn distillers dried grains with solubles could be useful commercially as a substrate for A. niger citric acid production.

Rhodospirillum rubrum: utilization of condensed corn solubles for poly-(3-hydroxybutyrate-co-3-hydroxyvalerate) production.

AIMS: This study sought to develop a less expensive medium for growth of the polyhydroxyalkanoate-producing bacterium Rhodospirillum rubrum from the ethanol production coproduct, condensed corn solubles (CCS). METHODS AND RESULTS: Small-scale trials using R. rubrum were performed in aerated or anaerobic stoppered serum bottles filled with media. The CCS (240 g l(-1)) achieved a maximum cell density and growth rate comparable with the defined supplemented malate-ammonium medium (mSMN) or tryptic soy broth. Microaerophilic solubles medium cultures exhibited significantly higher maximum cell densities and growth rates than did strictly anaerobic cultures; while illumination, nickel or biotin addition had no effect. Growth of R. rubrum in a pH controlled bioreactor was significantly better in CCS (240 g l(-1)) than in mSMN medium and supported production of 0.36% (cell dry weight) poly-(3-hydroxybutyrate-Co-3-hydroxyvalerate) after 24 h. CONCLUSIONS: A CCS medium was devised that supported R. rubrum growth for biopolymer production as effective as the defined medium. SIGNIFICANCE AND IMPACT OF THE STUDY: This study demonstrates that a more economical medium can be developed for biopolymer production using a low value coproduct from ethanol production. The impact is that this inexpensive solubles medium may make it more economical to produce the biopolymer on a commercial scale.

Citric acid production by Aspergillus niger on wet corn distillers grains.

AIMS: To determine which citric acid-producing strain of Aspergillus niger utilized wet corn distillers grains most effectively to produce citric acid. METHODS AND RESULTS: Citric acid and biomass production by the fungal strains were analysed on the untreated grains or autoclaved grains using an enzyme assay and a gravimetric method respectively. Fungal citric acid production on the grains was found to occur on the untreated or autoclaved grains. The highest citric acid level on the grains was produced by A. niger ATCC 9142. The autoclaved grains supported less citric acid production by the majority of strains screened. Biomass production by the fungal strains on the untreated or autoclaved grains was quite similar. The highest citric acid yields for A. niger ATCC 9142, ATCC 10577, ATCC 11414, ATCC 12846 and ATCC 26550 were found on the untreated grains. Treatment of the grains had little effect on citric acid yields based on reducing sugars consumed by A. niger ATCC 9029 and ATCC 201122. CONCLUSIONS: It is feasible for citric acid-producing strains of A. niger to excrete citric acid on wet corn distillers grains whether the grains are treated or untreated. The most effective citric acid-producing strain of A. niger was ATCC 9142. SIGNIFICANCE AND IMPACT OF THE STUDY: The study shows that the ethanol processing co-product wet corn distillers grains could be utilized as a substrate for the commercial production of citric acid by A. niger without treatment of the grains.

Regulation of pyrimidine synthesis in Pseudomonas resinovorans.

AIMS: To investigate the regulation of de novo pyrimidine biosynthesis in the bacterium Pseudomonas resinovorans ATCC 14235. METHODS AND RESULTS: The pyrimidine biosynthetic pathway enzymes were measured in cell extracts from P. resinovorans ATCC 14235 and from an auxotroph lacking orotate phosphoribosyltransferase activity. Pyrimidine biosynthetic pathway enzyme activities in ATCC 14235 were affected by the addition of pyrimidine bases to the culture medium. The de novo enzyme activities of the phosphoribosyltransferase mutant strain increased after pyrimidine starvation indicating possible repression of the pathway by a pyrimidine-related compound. Aspartate transcarbamoylase activity in ATCC 14235 was inhibited in vitro by ATP, UTP and pyrophosphate. CONCLUSIONS: Pyrimidine biosynthesis in P. resinovorans was regulated at the level of enzyme synthesis and at the level of activity for aspartate transcarbamoylase. Its regulation of enzyme synthesis seemed to be similar to what has been observed in the taxonomically related species Pseudomonas oleovorans. SIGNIFICANCE AND IMPACT OF THE STUDY: This study found that pyrimidine biosynthesis is regulated in P. resinovorans. This could prove helpful to future studies investigating polyhydroxyalkanoate production by the bacterium.

Regulation of pyrimidine nucleotide formation in Pseudomonas reptilivora.

AIMS: To study the regulation of de novo pyrimidine biosynthesis in the pathogenic bacterium Pseudomonas reptilivora ATCC 14836. METHODS AND RESULTS: The pyrimidine biosynthetic pathway enzymes were assayed in extracts of Ps. reptilivora ATCC 14836 cells and of cells from an auxotroph lacking aspartate transcarbamoylase activity. Pyrimidine biosynthetic pathway enzyme activities in ATCC 14836 were influenced by the addition of pyrimidine bases to the culture medium with orotic acid addition inducing dihydroorotase activity. Pyrimidine starvation of the transcarbamoylase mutant strain increased its de novo enzyme activities suggesting that the de novo pathway was also subject to repression by a pyrimidine-related compound. Aspartate transcarbamoylase activity in ATCC 14836 was inhibited in vitro by pyrophosphate and ATP. CONCLUSIONS: Regulation of pyrimidine biosynthesis in Ps. reptilivora was observed at the level of enzyme synthesis and at the level of activity for aspartate transcarbamoylase. Its regulation of enzyme synthesis seemed to be more highly controlled than what was observed in the related species Ps. fluorescens. SIGNIFICANCE AND IMPACT OF THE STUDY: This investigation found that pyrimidine biosynthesis is controlled in Ps. reptilivora. This could prove helpful to future studies exploring its pathogenicity.

Control of pyrimidine synthesis in Pseudomonas fragi.

AIMS: To study the regulation of the de novo pyrimidine biosynthetic enzymes in the food-spoilage agent Pseudomonas fragi ATCC 4973. METHODS AND RESULTS: The de novo pyrimidine biosynthetic enzymes were measured in extracts of Ps. fragi ATCC 4973 cells and of cells from auxotrophs deficient for dihydroorotase or OMP decarboxylase activity. Pyrimidine biosynthetic enzyme activities in ATCC 4973 were influenced by pyrimidine supplementation to the culture medium. The pyrimidine limitation of each auxotroph elevated the de novo enzyme activities, indicating that this pathway may be repressible by a pyrimidine-related compound. Aspartate transcarbamoylase activity in ATCC 4973 was inhibited in vitro by pyrophosphate and purine or pyrimidine nucleotides. CONCLUSIONS: Pyrimidine synthesis in Ps. fragi appeared to be controlled at the transcriptional level and at the level of activity for aspartate transcarbamoylase. Its transcriptional regulation seemed to be more highly controlled than what was observed in the closely related species Pseudomonas putida and Pseudomonas fluorescens. SIGNIFICANCE AND IMPACT OF THE STUDY: This study demonstrates that pyrimidine synthesis is regulated in Ps. fragi. This could prove useful to future studies examining its biological control and its taxonomic assignment.

Isolation of a mutant strain of Pseudomonas sp ATCC 31461 exhibiting elevated polysaccharide production.

A mutant strain of the bacterium Pseudomonas sp. ATCC 31461 that exhibited elevated production of the polysaccharide gellan on glucose or corn syrup as a carbon source was isolated. Gellan production by the mutant strain was about twofold higher than its parent strain on glucose or corn syrup after 48 h of growth, and about 1.4-fold higher after 72 h. An increase in biomass production was not correlated with enhanced gellan synthesis by the mutant strain. The increased gellan production by the mutant strain on either carbon source resulted in an increase in its culture medium viscosity and the viscosity of the isolated polysaccharide produced by glucose-grown cells. No differences in the glucuronic acid content of the polysaccharides produced by the mutant and parent strains were observed.

Pyrimidine biosynthesis in Pseudomonas oleovorans.

AIMS: To investigate the regulation of de novo pyrimidine biosynthesis in the polyhydroxyalkanoate-producing bacterium Pseudomonas oleovorans at the level of enzyme synthesis and at the level of aspartate transcarbamoylase activity. METHODS AND RESULTS: The effect of pyrimidine supplementation on the pyrimidine biosynthetic pathway enzyme activities was analysed relative to carbon source. Two uracil auxotrophs of P. oleovorans were isolated that were deficient for aspartate transcarbamoylase or dihydroorotase activity. Pyrimidine limitation of these auxotrophs increased the de novo pathway activities to varying degrees depending on the pathway mutation and the carbon source utilized. At the level of aspartate transcarbamoylase activity, pyrophosphate and uridine ribonucleotides were found to be strongly inhibitory of the Ps. oleovorans enzyme. CONCLUSIONS: Pyrimidine biosynthesis is regulated in Ps. oleovorans. Taxonomically, the regulation of the pyrimidine biosynthetic pathway appeared dissimilar from previously studied Pseudomonas species. SIGNIFICANCE AND IMPACT OF THE STUDY: New insights regarding the regulation of nucleic acid metabolism are provided that could prove significant during the genetic manipulation of Ps. oleovorans to increase the synthesis of polyhydroxyalkanoates.

Polysaccharide production by immobilized Aureobasidium pullulans cells in batch bioreactors.

Cells of the fungus Aureobasidium pullulans ATCC 201253 were entrapped within 4% agar cubes or 5% calcium alginate beads and were examined for their production of the polysaccharide pullulan in batch bioreactors. The batch bioreactors were utilized twice for 168 hours of polysaccharide production in medium containing corn syrup as a carbon source. The agar-entrapped cells produced nearly equivalent pullulan concentrations during both production cycles. The alginate-entrapped cells produced higher polysaccharide levels during the second cycle compared to the levels observed during the initial cycle. The agar-entrapped cells elaborated a polysaccharide with a higher pullulan content than did the alginate-entrapped cells during both production cycles.

Polysaccharide production by a reduced pigmentation mutant of Aureobasidium pullulans NYS-1.

AIMS: To isolate a reduced pigmentation mutant of Aureobasidium pullulans NYS-1 and characterize its cellular pigmentation plus its polysaccharide and biomass production relative to carbon source. METHODS AND RESULTS: Cellular pigmentation, polysaccharide levels and biomass production by the isolated mutant NYSRP-1 were analysed relative to carbon source. Cellular pigmentation of the mutant was lower than its parent strain using either carbon source. The mutant elaborated higher polysaccharide levels on sucrose than on corn syrup. The pullulan content of the polysaccharide synthesized and biomass production by the mutant rose as the carbon source concentration was increased. CONCLUSION: It is feasible to isolate a reduced pigmentation mutant from strain NYS-1 that exhibits elevated polysaccharide production using corn syrup as a carbon source. SIGNIFICANCE AND IMPACT OF THE STUDY: The mutant provides an advantage for commercial pullulan production because of its reduced pigmentation and enhanced polysaccharide synthesis.

Effect of culture medium pH on bacterial gellan production.

The effect of the initial pH of the culture medium used in the production of the exopolysaccharide gellan by the bacterium Pseudomonas species ATCC 31461, when glucose or corn syrup served as the carbon source, was investigated. With glucose as the carbon source, exopolysaccharide formation was highest after 72 h of growth when the initial pH of the culture medium was 6.8 to 7.4. Polysaccharide production by the bacterial cells grown on corn syrup for 72 h was maximal when the initial pH of the medium was 7.0 or 7.2. Cell weights of the strain after 72 h tended to be higher for the glucose-grown cells than for the corn syrup-grown cells.

Pyrimidine base catabolism in Pseudomonas putida biotype B.

Reductive catabolism of the pyrimidine bases uracil and thymine was found to occur in Pseudomonas putida biotype B. The pyrimidine reductive catabolic pathway enzymes dihydropyrimidine dehydrogenase, dihydropyrimidinase and N-carbamoyl-beta-alanine amidohydrolase activities were detected in this pseudomonad. The initial reductive pathway enzyme dihydropyrimidine dehydrogenase utilized NADH or NADPH as its nicotinamide cofactor. The source of nitrogen in the culture medium influenced the reductive pathway enzyme activities and, in particular, dihydropyrimidinase activity was highly affected by nitrogen source. The reductive pathway enzyme activities in succinate-grown P. putida biotype B cells were induced when uracil served as the nitrogen source.

Ability of casamino acids to support gellan production by Sphingomonas paucimobilis ATCC 31461.

The ability of casamino acids and vitamin-assay casamino acids to support gellan production by Sphingomonas paucimobilis ATCC 31461 was examined in a medium containing glucose or corn syrup as the carbon source relative to yeast extract supplementation. When glucose or corn syrup served as the carbon source, the presence of yeast extract in the growth medium stimulated gellan production by strain ATCC 31461 on casamino acids. Using vitamin-assay casamino acids as the nitrogen source, the addition of vitamins lowered gellan synthesis by glucose-grown cells regardless of yeast extract supplementation while gellan elaboration by corn syrup-grown strain ATCC 31461 cells could only be increased by supplementing vitamins into medium lacking yeast extract. Independent of carbon source, the absence of yeast extract in the medium reduced biomass production. Biomass production by the strain grown on either carbon source was increased by supplementing vitamins in the medium containing yeast extract.

Role of cytosine deaminase and beta-alanine-pyruvate transaminase in pyrimidine base catabolism by Burkholderia cepacia.

A determination of the possible role of the salvage enzyme cytosine deaminase or beta-alanine-pyruvate transaminase in the catabolism of the pyrimidine bases uracil and thymine by the opportunistic pathogen Burkholderia cepacia ATCC 25416 was undertaken. It was of interest to learn whether these enzymes were influenced by cell growth on pyrimidine bases and their respective catabolic products to the same degree as the pyrimidine reductive catabolic enzymes were. It was found that cytosine deaminase activity was influenced very little by cell growth on the pyrimidines tested. Using glucose as the carbon source, only B. cepacia growth on 5-methylcytosine as a nitrogen source increased deaminase activity by about three-fold relative to (NH4)2SO4-grown cells. In contrast, the activity of beta-alanine-pyruvate transaminase was observed to be at least double in glucose-grown ATCC 25416 cells when pyrimidine bases and catabolic products served as nitrogen sources instead of (NH4)2SO4. Transaminase activity in the B. cepacia glucose-grown cells was maximal after the strain was grown on either uracil or 5-methylcytosine as a nitrogen source compared to (NH4)2SO4-grown cells. A possible role for beta-alanine-pyruvate transaminase in pyrimidine base catabolism by B. cepacia would seem to be suggested from the similarity in how its enzyme activity responded to cell growth on pyrimidine bases and catabolic products when compared to the response of the three reductive catabolic enzymes.

Exopolysaccharide production by entrapped cells of the fungus Aureobasidium pullulans ATCC 201253.

The production of the exopolysaccharide pullulan using entrapped cells of the fungus Aureobasidium pullulans ATCC 201253 was investigated. Fungal cells entrapped in agarose or carrageenan were capable of elaborating pullulan for 2 production cycles. Those fungal cells entrapped in carrangeenan were more productive than the agarose-immobilized cells during the initial cycle while the reverse was true during the second production cycle. The agarose-entrapped cells synthesized polysaccharide with a higher pullulan content than did the carrageenan-immobilized cells. Fungal cells entrapped in carrageenan demonstrated a lower degree of leakage than did those entrapped in agarose.

Effect of nitrogen source on pullulan production by Aureobasidium pullulans grown in a batch bioreactor.

Pullulan production by Aureobasidium pullulans ATCC 201253 using selected nitrogen sources was studied in a medium using corn syrup as a carbon source. Independent of the corn syrup concentration present, the use of corn steep liquor or hydrolysed soy protein as a nitrogen source instead of ammonium sulphate did not elevate polysaccharide production by ATCC 201253 cells grown in an aerated, batch bioreactor containing 4 litres of medium. Pullulan production on corn steep liquor or hydrolysed soy protein as a nitrogen source became more comparable as the concentration of corn syrup was increased. Cell weights after 7 days of growth on any of the nitrogen sources were similar. The viscosity of the polysaccharide on day 7 was highest for cells grown on ammonium sulphate and 12.5% corn syrup. The pullulan content of the polysaccharide elaborated by ammonium sulphate-grown cells on day 7 decreased as the corn syrup level rose in the medium while the pullulan content of polysaccharide produced by cells grown on corn steep liquor or soytone generally increased.

Isolation and characterization of an Escherichia coli B mutant strain defective in uracil catabolism.

A reductive pathway of uracil catabolism was shown to be functioning in Escherichia coli B ATCC 11303 by virtue of thin-layer chromatographic and enzyme analyses. A mutant defective in uracil catabolism was isolated from this strain and subsequently characterized. The three enzyme activities associated with the reductive pathway of pyrimidine catabolism were detectable in the wild-type E. coli B cells, while the mutant strain was found to be deficient for dihydropyrimidine dehydrogenase activity. The dehydrogenase was shown to utilize NADPH as its nicotinamide cofactor. Growth of ATCC 11303 cells on uracil or glutamic acid instead of ammonium sulfate as a nitrogen source increased the reductive pathway enzyme activities. The mutant strain exhibited increased catabolic enzyme activities after growth on ammonium sulfate or glutamic acid.

Pyrimidine biosynthesis in Pseudomonas stutzeri ATCC 17588.

The de novo pyrimidine biosynthetic enzymes in the denitrifying bacterium Pseudomonas stutzeri ATCC 17588 were assayed and their activities were lower in glucose-grown cells than in succinate-grown cells. When P. stutzeri was grown in the presence of uracil, the de novo enzyme activities in succinate-grown cells were lowered while they remained largely unchanged in glucose-grown cells. A uracil auxotroph of P. stutzeri, deficient for aspartate transcarbamoylase activity, was isolated and its auxotrophic requirement was met by only uracil and cytosine. The inability of pyrimidine ribonucleosides to meet the auxotrophic requirement was related to the limited ability of P. stutzeri to transport uridine and cytidine. Pyrimidine limitation of the auxotroph elevated the de novo enzyme activities indicating that this pathway may be repressible by a uracil-related compound in succinate-grown P. stutzeri cells. Regulation of pyrimidine synthesis in P. stutzeri was similar to that observed for other pseudomonads classified within rRNA homology group I.