Consensus Statement of the IAP - Neurodevelopmental Chapter On Neurodevelopmental Disorders Habilitation Process: Strategic Plan for Prevention, Early Detection and Early Intervention.

JUSTIFICATION: Neurodevelopmental disorders, as per DSM-V, are described as a group of conditions with onset in the development period of childhood. There is a need to distinguish the process of habilitation and rehabilitation, especially in a developing country like India, and define the roles of all stakeholders to reduce the burden of neurodevelopmental disorders. PROCESS: Subject experts and members of Indian Academy of Pediatrics (IAP) Chapter of Neurodevelopmental Pediatrics, who reviewed the literature on the topic, developed key questions and prepared the first draft on guidelines. The guidelines were then discussed by the whole group through online meetings, and the contentious issues were discussed until a general consensus was arrived at. Following this, the final guidelines were drafted by the writing group and approved by all contributors. OBJECTIVES: These guidelines aim to provide practical clinical guidelines for pediatricians on the prevention, early diagnosis and management of neurodevelopmental disorders (NDDs) in the Indian settings. It also defines the roles of developmental pediatricians and development nurse counselor. STATEMENT: There is a need for nationwide studies with representative sampling on epidemiology of babies with early NDD in the first 1000 days in India. Specific learning disability (SLD) has been documented as the most common NDD after 6 years in India, and special efforts should be made to establish the epidemiology of infants and toddlers at risk for SLD, where ever measures are available. Preconception counseling as part of focusing on first 1000 days; Promoting efforts to organize systematic training programs in Newborn Resuscitation Program (NRP); Lactation management; Developmental follow-up and Early stimulation for SNCU/ NICU graduates; Risk stratification of NICU graduates, Newborn Screening; Counseling parents; Screening for developmental delay by trained professionals using simple validated Indian screening tools at 4, 8, 12, 18 and 24 months; Holistic assessment of 10 NDDs at child developmental clinics (CDCs) / district early intervention centre (DEICs) by multidisciplinary team members; Confirmation of diagnosis by developmental pediatrician/developmental neurologist/child psychiatrist using clinical/diagnostic tools; Providing parent guided low intensity multimodal therapies before 3 years age as a center-based or home-based or community-based rehabilitation; Developmental pediatrician to seek guidance of pediatric neurologist, geneticist, child psychiatrist, physiatrist, and other specialists, when necessary; and Need to promote ongoing academic programs in clinical child development for capacity building of community based therapies, are the chief recommendations.

Parenting stress and associated factors in healthcare workers after the second wave of COVID-19 in India: a two-center cross-sectional study.

Background: High parenting stress (PS) in members of the general population during the COVID-19 pandemic was exacerbated by work-, family-, and child-related factors. However, the negative effects of PS on the mental health and work participation of healthcare workers (HCWs) have received limited attention. This study aimed to examine the proportion of severe PS among HCWs and identify its contributory factors. Methods: This cross-sectional survey was conducted in two COVID-19-care hospitals attached to medical colleges in India between November 1 and December 24, 2021, following the delta variant-driven second wave of COVID-19. The study recruited 662 HCW parent and child dyads (aged 1.5-18 years) and assessed workplace, family, and child-related characteristics. The Parenting Stress Scale (PSS) and Child Behavior Checklist (CBCL) were used to identify severe PS and child behavioral issues, respectively. Univariable and multivariable logistic regression analyzes were used to identify the significant and independent risk factors associated with severe PS, respectively. Results: Equal proportions of medical and paramedical HCWs completed the survey [mean age: 36.96 ± 5.89; female: 466 (70%)]. The median PSS score of HCWs was 33 [interquartile range (IQR): 28-39], and 23% (155/662) of the HCW parents experienced severe PS. The independent predictors of severe PS included the female sex [adjusted odds ratio (aOR): 3.31; 95% confidence interval (CI): 1.74-6.29], HCWs with >15-day postings in COVID-19 care (aOR: 3.74; 95% CI: 1.53-9.16), having children with behavioral issues (aOR: 3.49; 95% CI: 1.29-9.48), HCWs at the Dehradun center (aOR: 2.25; 95% CI: 1.24-4.10), having an HCW spouse simultaneously working in COVID-19 care (aOR: 1.88; 95% CI: 1.01-3.49), and HCWs with joint families (aOR: 1.93; 95% CI: 1.17-3.18). Conclusion: Overall, 23% of the cohort of HCWs continued to experience severe PS after the second COVID-19 wave driven by the delta variant in India. Routine screening of HCWs for PS using the PSS or similar measures, anticipatory guidance for parenting, and targeting at-risk HCWs with appropriate supportive measures may help reduce the incidence of severe PS and optimize the participation of HCWs in the fight against current and future pandemic-like situations.

Stress among mothers of children with Autism Spectrum Disorder in comparison to children with & without special health care needs.

PURPOSE: Parenting a child with special health care needs (SHCN) is often stressful. This study aimed to measure and compare stress among mothers of children with (a) Autism Spectrum Disorder (ASD) - ASD group, (b) Developmental delay without ASD group, (c) SHCN without developmental delay group, and (d) Typically developing group. To assess factors associated with maternal stress in children with developmental disorders. METHODS: A cross-sectional analytical study was performed with children aged 2-12 years and their mothers. The study population was classified into four groups as defined above help of detailed history, developmental & behavioral assessments, psychological assessments, and Child Special Health Care Needs Screener (CSHCN). Parental Stress Scale (PSS) Questionnaire was administered. The main outcome measurement was the PSS and various factors affecting it. RESULTS: The mothers of the ASD group reported a high stress score (50.4±11.4) compared to SHCN without developmental delay group (38.2±8.8) and the Typically developing group (22.3±3.3) (p < 0.05) and higher but not significant stress than Developmental delay without ASD group (45.3±9.6, p > 0.05). Maladaptive behavioral issues and irregular interventions were the factors contributing to higher parental stress in the ASD group (p < 0.05). A moderate positive correlation was observed in rewarding and challenging scores of PSS among mothers of the ASD group, Developmental delay without ASD group, and SHCN without developmental delay group. CONCLUSION: Mothers of the ASD group perceived higher stress as compared to SHCN without developmental delay group and Typically developing group. Evaluation of stress and stressors is crucial for holistic management of ASD.

Diagnosis and Management of Global Development Delay: Consensus Guidelines of Growth, Development and Behavioral Pediatrics Chapter, Neurology Chapter and Neurodevelopment Pediatrics Chapter of the Indian Academy of Pediatrics.

JUSTIFICATION: Global developmental delay (GDD) is a relatively common neurodevelopmental disorder; however, paucity of published literature and absence of uniform guidelines increases the complexity of clinical management of this condition. Hence, there is a need of practical guidelines for the pediatrician on the diagnosis and management of GDD, summarizing the available evidence, and filling in the gaps in existing knowledge and practices. PROCESS: Seven subcommittees of subject experts comprising of writing and expert group from among members of Indian Academy of Pediatrics (IAP) and its chapters of Neurology, Neurodevelopment Pediatrics and Growth Development and Behavioral Pediatrics were constituted, who reviewed literature, developed key questions and prepared the first draft on guidelines after multiple rounds of discussion. The guidelines were then discussed by the whole group in an online meeting. The points of contention were discussed and a general consensus was arrived at, after which final guidelines were drafted by the writing group and approved by all contributors. The guidelines were then approved by the Executive Board of IAP. Guidelines: GDD is defined as significant delay (at least 2 standard deviations below the mean with standardized developmental tests) in at least two developmental domains in children under 5 years of age; however, children whose delay can be explained primarily by motor issues or severe uncorrected visual/hearing impairment are excluded. Severity of GDD can be classified as mild, moderate, severe and profound on adaptive functioning. For all children, in addition to routine surveillance, developmental screening using standardized tools should be done at 9-12 months,18-24 months, and at school entry; whereas, for high risk infants, it should be done 6-monthly till 24 months and yearly till 5 years of age; in addition to once at school entry. All children, especially those diagnosed with GDD, should be screened for ASD at 18-24 months, and if screen negative, again at 3 years of age. It is recommended that investigations should always follow a careful history and examination to plan targeted testing and, vision and hearing screening should be done in all cases prior to standardized tests of development. Neuro-imaging, preferably magnetic resonance imaging of the brain, should be obtained when specific clinical indicators are present. Biochemical and metabolic investigations should be targeted towards identifying treatable conditions and genetic tests are recommended in presence of clinical suspicion of a genetic syndrome and/or in the absence of a clear etiology. Multidisciplinary intervention should be initiated soon after the delay is recognized even before a formal diagnosis is made, and early intervention for high risk infants should start in the nursery with developmentally supportive care. Detailed structured counselling of family regarding the diagnosis, etiology, comorbidities, investigations, management, prognosis and follow-up is recommended. Regular targeted follow-up should be done, preferably in consultation with a team of experts led by a developmental pediatrician/ pediatric neurologist.

Cognitive function and behavioral problems in children born to mothers with preeclampsia: an Indian study.

Studies from high-income countries report associations of preeclampsia (PE) with reduced cognitive function and adverse behavioural outcomes in children. We examined these associations in Indian children aged 5-7 years. Children of mothers with PE (n=74) and without PE (non-PE; n=234) were recruited at delivery at Bharati Hospital, Pune, India. The cognitive performance was assessed using 3 core tests from the Kaufman Assessment Battery and additional tests including Verbal fluency, Kohs block design, and Coding A (from Wechsler Intelligence Scale for Children). The parent-reported Strengths and Difficulties Questionnaire (SDQ) was used to assess children's behavioral characteristics. Scores were compared between children from PE and non-PE groups, and associations analyzed further using regression models, adjusted for potential confounders. After adjusting for age, sex, socio-economic status and maternal education, children of PE mothers had lower Kohs block design scores (adjusted odds ratio per score category 0.57, [95% CI 0.34-0.96] p=0.034; 0.62 [95%CI (0.36, 1.07), p=0.09 on further adjustment for birth weight and gestation) compared to children of mothers without PE. In the SDQ, there was a lower prevalence of abnormal 'conduct problem' scores in PE group than non-PE group (OR=0.33, 95% CI 0.13-0.83, p=0.018, in the fully adjusted model); there were no differences for other behavioral domains. This preliminary study in Indian children suggests that fetal exposure to maternal PE may have an adverse impact on visuo-spatial performance but does not adversely affect behavior. Further studies with larger sample sizes are essential to understand effects of maternal PE on cognitive/behavioral outcomes in children.

Multicenter Evaluation of 434 Hospital Deaths From COVID-19: How Can We Improve End-of-Life Care During a Pandemic?

CONTEXT: The pandemic has substantially increased the workload of hospital palliative care providers, requiring them to be responsive and innovative despite limited information on the specific end of life care needs of patients with COVID-19. Multi-site data detailing clinical characteristics of patient deaths from large populations, managed by specialist and generalist palliative care providers are lacking. OBJECTIVES: To conduct a large multicenter study examining characteristics of COVID-19 hospital deaths and implications for care. METHODS: A multi-center retrospective evaluation examined 434 COVID-19 deaths in 5 hospital trusts over the period March 23, 2020 to May 10, 2020. RESULTS: Eighty three percent of patients were over 70%-32% were admitted from care homes. Diagnostic timing indicated over 90% of those who died contracted the virus in the community. Dying was recognized in over 90% of patients, with the possibility of dying being identified less than 48 hours from admission for a third. In over a quarter, death occurred less than 24 hours later. Patients who were recognized to be dying more than 72 hours prior to death are most likely to have access to medication for symptom control. CONCLUSION: This large multicenter study comprehensively describes COVID-19 deaths throughout the hospital setting. Clinicians are alert to and diagnose dying appropriately in most patients. Outcomes could be improved by advance care planning to establish preferences, including whether hospital admission is desirable, and alongside this, support the prompt use of anticipatory subcutaneous medications and syringe drivers if needed. Finally, rapid discharges and direct hospice admissions could better utilize hospice beds and improve care.

Consensus Statement of Indian Academy of Pediatrics on Early Childhood Development.

JUSTIFICATION: Early Childhood Development (ECD) has lifelong impact on learning, education, productivity, socio-emotional functioning, health and disease. A Consensus Statement for promoting ECD is needed to improve patient care and promote research. PROCESS: Indian Academy of Pediatrics convened a National Consultative Meeting on 20 September, 2019 at Surat to discuss the way forward for pediatricians in ECD and form a consensus advisory statement. Experts from Chapters of Infant and Young Child Feeding, Neurodevelopmental Pediatrics, Neonatology, Growth Development and Behavior, Adolescent Health Academy, Parenting for Peace and UNICEF participated. OBJECTIVES: To formulate, endorse and disseminate a consensus advisory statement of working at current levels of resources and to build future framework for ECD from Indian perspective. CONCLUSIONS: Interventions for ECD should begin from conception to adolescence, prioritized in first 3 years, inclusive and equitable for all, especially for high risk, vulnerable and marginalized families. Pediatric clinics can play a pivotal role as cost effective delivery points for guidance and interventions. Age appropriate approaches, active care giver's involvement, advocacy and integration with different sectors, community and policy makers should be done to enable supportive environment. Research should be promoted into finding cost effective novel scalable interventions.

Time-dependent behavioral, neurochemical, and metabolic dysregulation in female C57BL/6 mice caused by chronic high-fat diet intake.

High-fat diet (HFD) induced obesity is associated not only with metabolic dysregulation, e.g., impaired glucose homeostasis and insulin sensitivity, but also with neurological dysfunction manifested with aberrant behavior and/or neurotransmitter imbalance. Most studies have examined HFD's effects predominantly in male subjects, either in the periphery or on the brain, in isolation and after a finite feeding period. In this study, we evaluated the time-course of selected metabolic, behavioral, and neurochemical effects of HFD intake in parallel and at multiple time points in female (C57BL/6) mice. Peripheral effects were evaluated at three feeding intervals (short: 5-6 weeks, long: 20-22 weeks, and prolonged: 33-36 weeks). Central effects were evaluated only after long and prolonged feeding durations; we have previously reported those effects after the short (5-6 weeks) feeding duration. Ongoing HFD feeding resulted in an obese phenotype characterized by increased visceral adiposity and, after prolonged HFD intake, an increase in liver and kidney weights. Peripherally, 5 weeks of HFD intake was sufficient to impair glucose tolerance significantly, with the deleterious effects of HFD being greater with prolonged intake. Similarly, 5 weeks of HFD consumption was sufficient to impair insulin sensitivity. However, sensitivity to insulin after prolonged HFD intake was not different between control, low-fat diet (LFD) and HFD-fed mice, most likely due to age-dependent decrease in insulin sensitivity in the LFD-fed mice. HFD intake also induced bi-phasic hepatic inflammation and it increased gut permeability. Behaviorally, prolonged intake of HFD caused mice to be hypoactive and bury fewer marbles in a marble burying task; the latter was associated with significantly impaired hippocampal serotonin homeostasis. Cognitive (short-term recognition memory) function of mice was unaffected by chronic HFD feeding. Considering our prior findings of short-term (5-6 weeks) HFD-induced central (hyperactivity/anxiety and altered ventral hippocampal neurochemistry) effects and our current results, it seems that in female mice some metabolic/inflammatory dysregulations caused by HFD, such as gut permeability, appear early and persist, whereas others, such as glucose intolerance, are exaggerated with continuous HFD feeding; behaviorally, prolonged HFD consumption mainly affects locomotor activity and anxiety-like responses, likely due to the advanced obesity phenotype; neurochemically, the serotonergic system appears to be most sensitive to continued HFD feeding.

A Neoglycoconjugate Containing the Human Milk Sugar LNFPIII Drives Anti-Inflammatory Activation of Antigen Presenting Cells in a CD14 Dependent Pathway.

The milk pentasaccharide LNFPIII has therapeutic action for metabolic and autoimmune diseases and prolongs transplant survival in mice when presented as a neoglycoconjugate. Within LNFPIII is the Lewisx trisaccharide, expressed by many helminth parasites. In humans, LNFPIII is found in human milk and also known as stage-specific embryonic antigen-1. LNFPIII-NGC drives alternative activation of macrophages and dendritic cells via NFκB activation in a TLR4 dependent mechanism. However, the connection between LNFPIII-NGC activation of APCs, TLR4 signaling and subsequent MAP kinase signaling leading to anti-inflammatory activation of APCs remains unknown. In this study we determined that the innate receptor CD14 was essential for LNFPIII-NGC induction of both ERK and NFkB activation in APCs. Induction of ERK activation by LNFPIII-NGC was completely dependent on CD14/TLR4-Ras-Raf1/TPL2-MEK axis in bone marrow derived dendritic cells (BMDCs). In addition, LNFPIII-NGC preferentially induced the production of Th2 "favoring" chemokines CCL22 and matrix metalloprotease protein-9 in a CD14 dependent manner in BMDCs. In contrast, LNFPIII-NGC induces significantly lower levels of Th1 "favoring" chemokines, MIP1α, MIP1ß and MIP-2 compared to levels in LPS stimulated cells. Interestingly, NGC of the identical human milk sugar LNnT, minus the alpha 1-3 linked fucose, failed to activate APCs via TLR4/MD2/CD14 receptor complex, suggesting that the alpha 1-3 linked fucose in LNFPIII and not on LNnT, is required for this process. Using specific chemical inhibitors of the MAPK pathway, we found that LNFPIII-NGC induction of CCL22, MMP9 and IL-10 production was dependent on ERK activation. Over all, this study suggests that LNFPIII-NGC utilizes CD14/TLR4-MAPK (ERK) axis in modulating APC activation to produce anti-inflammatory chemokines and cytokines in a manner distinct from that seen for the pro-inflammatory PAMP LPS. These pathways may explain the in vivo therapeutic effect of LNFPIII-NGC treatment for inflammation based diseases.

CD14 influences host immune responses and alternative activation of macrophages during Schistosoma mansoni infection.

Antigen-presenting cell (APC) plasticity is critical for controlling inflammation in metabolic diseases and infections. The roles that pattern recognition receptors (PRRs) play in regulating APC phenotypes are just now being defined. We evaluated the expression of PRRs on APCs in mice infected with the helminth parasite Schistosoma mansoni and observed an upregulation of CD14 expression on macrophages. Schistosome-infected Cd14(-/-) mice showed significantly increased alternative activation of (M2) macrophages in the livers compared to infected wild-type (wt) mice. In addition, splenocytes from infected Cd14(-/-) mice exhibited increased production of CD4(+)-specific interleukin-4 (IL-4), IL-5, and IL-13 and CD4(+)Foxp3(+)IL-10(+) regulatory T cells compared to cells from infected wt mice. S. mansoni-infected Cd14(-/-) mice also presented with smaller liver egg granulomas associated with increased collagen deposition compared to granulomas in infected wt mice. The highest expression of CD14 was found on liver macrophages in infected mice. To determine if the Cd14(-/-) phenotype was in part due to increased M2 macrophages, we adoptively transferred wt macrophages into Cd14(-/-) mice and normalized the M2 and CD4(+) Th cell balance close to that observed in infected wt mice. Finally, we demonstrated that CD14 regulates STAT6 activation, as Cd14(-/-) mice had increased STAT6 activation in vivo, suggesting that lack of CD14 impacts the IL-4Rα-STAT6 pathway, altering macrophage polarization during parasite infection. Collectively, these data identify a previously unrecognized role for CD14 in regulating macrophage plasticity and CD4(+) T cell biasing during helminth infection.

Immunomodulatory glycan lacto-N-fucopentaose III requires clathrin-mediated endocytosis to induce alternative activation of antigen-presenting cells.

The mechanism of alternative activation of antigen-presenting cells (APCs) is largely unknown. Lacto-N-fucopentaose III (LNFPIII) is a biologically conserved pentasaccharide that contains the Lewis(x) trisaccharide. LNFPIII conjugates and schistosome egg antigens, which contain the Lewis(x) trisaccharide, drive alternative activation of APCs and induce anti-inflammatory responses in vivo, preventing inflammation-based diseases, including psoriasis, transplant organ rejection, and metabolic disease. In this study, we show that LNFPIII conjugates and schistosome egg antigens interact with APCs via a receptor-mediated process, requiring internalization of these molecules through a clathrin/dynamin-dependent but caveolus-independent endocytic pathway. Using inhibitors/small interfering RNA (siRNA) against dynamin and clathrin, we show for the first time that endocytosis of Lewis(x)-containing glycans is required to drive alternative maturation of antigen-presenting cells and Th2 immune responses. We identified mouse SIGNR-1 as a cell surface receptor for LNFPIII conjugates. Elimination of SIGNR-1 showed no effect on uptake of LNFPIII conjugates, suggesting that other receptors bind to and facilitate uptake of LNFPIII conjugates. We demonstrate that disruption of actin filaments partially prevented the entry of LNFPIII conjugates into APCs and that LNFPIII colocalizes with both early and late endosomal markers and follows the classical endosomal pathway leading to lysosome maturation. The results of this study show that the ability of LNFPIII to induce alternative activation utilizes a receptor-mediated process that requires a dynamin-dependent endocytosis. Thus, key steps have been defined in the previously unknown mechanism of alternative activation that ultimately leads to induction of anti-inflammatory responses.

Polarization of host immune responses by helminth-expressed glycans.

Helminth parasites bias host CD4(+) T helper (Th) cells toward Th2 responses, drive alternative activation of macrophages, and expand T regulatory cells. Helminth-expressed carbohydrates play critical roles in driving much of this immune cell biasing. Studies on helminth glycans have focused on Lewis X, LDN, LDN-DF, other fucosylated structures, chitin, tyvelose, and trehalose, which interact with host antigen presenting cells (APCs) minimally via C-type lectins and/or Toll-like receptors (TLR). Here, we review recent findings on helminth glycan activation of APCs via C-type lectin/TLRs and introduce the concept that glycosylated helminth molecules require endocytosis to function as immune modulators. Second, we describe unpublished data showing that in vivo glycoconjugates comprising multiple copies of glycans on carriers are directly immune modulatory. Lastly, we discuss the observation that CD14 negatively regulates alternative activation of APCs during helminth infection. We close with a discussion on the use of immune modulatory glycans as vaccine adjuvants and as antiinflammatory therapeutics.

Mammalian DEAD box protein Ddx51 acts in 3' end maturation of 28S rRNA by promoting the release of U8 snoRNA.

Biogenesis of eukaryotic ribosomes requires a number of RNA helicases that drive molecular rearrangements at various points of the assembly pathway. While many ribosome synthesis factors are conserved among all eukaryotes, certain features of ribosome maturation, such as U8 snoRNA-assisted processing of the 5.8S and 28S rRNA precursors, are observed only in metazoan cells. Here, we identify the mammalian DEAD box helicase family member Ddx51 as a novel ribosome synthesis factor and an interacting partner of the nucleolar GTP-binding protein Nog1. Unlike any previously studied yeast helicases, Ddx51 is required for the formation of the 3' end of 28S rRNA. Ddx51 binds to pre-60S subunit complexes and promotes displacement of U8 snoRNA from pre-rRNA, which is necessary for the removal of the 3' external transcribed spacer from 28S rRNA and productive downstream processing. These data demonstrate the emergence of a novel factor that facilitates a pre-rRNA processing event specific for higher eukaryotes.

Polyadenylation and degradation of incomplete RNA polymerase I transcripts in mammalian cells.

Most transcripts in growing cells are ribosomal RNA precursors (pre-rRNA). Here, we show that in mammals, aberrant pre-rRNA transcripts generated by RNA polymerase I (Pol I) are polyadenylated and accumulate markedly after treatment with low concentrations of actinomycin D (ActD), which blocks the synthesis of full-length rRNA. The poly(A) polymerase-associated domain-containing protein 5 is required for polyadenylation, whereas the exosome is partly responsible for the degradation of the short aberrant transcripts. Thus, polyadenylation functions in the quality control of Pol I transcription in metazoan cells. The impact of excessive aberrant RNAs on the degradation machinery is an unrecognized mechanism that might contribute to biological properties of ActD.

Kinetic studies of constitutive human granulocyte-macrophage colony stimulating factor (hGM-CSF) expression in continuous culture of Pichia pastoris.

Extracellular human granulocyte-macrophage colony stimulating factor (hGM-CSF) expression was studied under the control of the GAP promoter in recombinant Pichia pastoris in a series of continuous culture runs (dilution rates from 0.025 to 0.2 h(-1)). The inlet feed concentration was also varied and the steady state biomass concentration increased proportionally demonstrating efficient substrate utilization and constancy of the biomass yield coefficient (Y(x/s)) for a given dilution rate. The specific product formation rate (q(P)) showed a strong correlation with dilution rates demonstrating growth associated product formation of hGM-CSF. The volumetric product concentration achieved at the highest feed concentration (4x) and a dilution rate of 0.2 h(-1) was 82 mg l(-1) which was 5-fold higher compared to the continuous culture run with 1x feed concentration at the lowest dilution rate thus translating to a 40 fold increase in the volumetric productivity. The specific product yield (Y(P/X)) increased slightly from 2 to 2.5 mg g(-1), with increasing dilution rates, while it remained fairly invariant, for all feed concentrations demonstrating negligible product degradation or feed back inhibition. The robust nature of this expression system would make it easily amenable to scale up for industrial production.