Wastewater treatment with microalgal-bacterial aggregates: The tradeoff between energy savings and footprint requirements.

Microalgal-bacterial aggregates (MBAs) have recently attracted significant attention as a potential replacement for conventional, suspended-growth wastewater treatment processes. This article evaluates MBAs for full-scale implementation from the perspective of oxygen supply, land use, and energy savings. The results suggest that under ideal conditions, photosynthesis and atmospheric diffusion would provide at most only 2.7% of the oxygen demand in a conventionally designed, nitrifying activated sludge process, which is equivalent to approximately 1.5% of typical treatment plant-wide energy requirements. The results also suggest that a wastewater treatment process using MBAs and relying on solar photosynthesis and atmospheric diffusion for oxygen would have nearly the same footprint as an equivalent well-mixed wastewater treatment pond. While photosynthesis and passive atmospheric diffusion are capable of providing significant oxygen for suspended-growth wastewater treatment processes, the tradeoffs between footprint requirements and energy savings should be carefully considered.

Assessment of knowledge and socioeconomic status of caregivers of children with malnutrition at a district hospital in Ghana.

Background: Malnutrition is a significant public health problem and is a major cause of morbidity and mortality in children. Aims: To assess knowledge and socioeconomic status of caregivers of children under 5 years with malnutrition at a district hospital in Ghana. Methods: Case Report forms were used to gather data in a cross-sectional study which was carried out among 189 caregivers and their children aged from zero to fifty-nine months at the Out-Patient Department clinic. Results: Most (80.95%) children had marasmus. Sixty-two point four-two percent had severe wasting, while 35.45% had mild stunting. The rest, 21.69% had moderate stunting; while only 2.12% severe stunting. Almost all caregivers (94.71%) had heard of exclusive breast feeding as a good feeding practice but only 58.20% practiced it. Most caregivers (68.26%) had no education or only up to basic level, p=0.035. The average number of children per family was 4.8 per household (SD: 1.69) with majority of them (64.55%) having 4-6 children per family and 13.23% of them had more than 7 children per family, p=0.009. More than a third (37.04%) of the caregivers earned less than a hundred Ghana cedis (GhC 100 [US$ 19] per month and 50.26% of them earned between GhC 101 (US$ 19) and GhC 500 (US$ 96) per month. Conclusion: Lower level of caregivers' education and large family size were risk factors for developing malnutrition among children.

Growing Up Can Be Hard to Do: Reimagining 1 Structurally Supportive Pediatric-to-Adult Transitions of Care from a Rights-Based Perspective.

Extended life expectancies and shifting dynamics in chronic disease have changed the landscape of public health interventions worldwide, with an increasing emphasis on chronic care. As a result, transition from pediatric to adult care for medically complex adolescents and young adults is a growing area of intervention. Transition medicine is a nascent field whose current emphasis is on middle- and high-income countries, and thus far its methods and discourse have reflected those origins. Through several case-based examples, this paper aims to highlight the possibilities of an analytic approach grounded in structural competency for transforming transition medicine through a human rights-based framework, with an emphasis on imagining a more global framework for transition medicine. Our cases highlight the disparities between patients navigating pediatric to adult-based care, illuminating social stigma, stratification between public and private insurances, engagement in risk-taking behaviors, family conflict, and challenges with transition readiness. To reimagine transition medicine so that it is based on human rights, we must prioritize structural solutions that embrace multisectoral integration and holistic mental health support rather than oppress and marginalize these critical systemic adaptations. We aim to reconfigure this scaffolding to center structures that integrate holistic well-being and imagine alternate realities to healing. Our work contributes to the literature bringing structural competency to new spaces of clinical practice, contextualizing new frontiers for the exploration of chronic diseases across diverse clinical contexts worldwide.

Spinal muscular atrophy in Ghanaian children confirmed by molecular genetic testing: a case series.

Spinal muscular atrophy (SMA) is an autosomal recessive inherited motor neuron disease characterized by progressive muscle weakness due to degeneration and loss of the anterior horn cells in the spinal cord and the brain stem nuclei from foetal life through infancy and childhood. SMA is prevalent in Ghanaian children, though not widely reported. Cases are likely missed or misdiagnosed due to lack of expertise and investigations. Newborn screening is not currently available in Ghana. The management remains supportive as newly approved genetic modifications therapies are currently not available. We present a retrospective folder review of children attending a tertiary pediatric neurology clinic who were diagnosed with SMA and confirmed by molecular genetic testing. Between January 2018 and August 2021, five (5) children from three families had molecular genetic tests confirming their diagnosis of SMA. Three (3) children had SMA I phenotype while 2 had SMA III phenotype. Two (2) of the 3 children with SMA I died from respiratory complications. The last surviving child with SMA I was diagnosed through newborn screening program overseas and received gene modification therapy. Careful history and physical examination remain the best approach to diagnosis as confirmatory genetic testing and supplemental investigations are not readily available. The current management of the children with SMA in Ghana include respiratory care, physiotherapy, and genetic counselling. Genetic modification therapies are currently not available.

Management of Pediatric Stroke - Challenges and Perspectives from Resource-limited Settings.

Childhood stroke is not as common as adult stroke, but it is underrecognized the world over. Diagnosis is often delayed due to lack of awareness not only by the lay public but also by emergency and front-line health care workers. Despite the relative rarity of childhood stroke, the impact on morbidity, mortality and the economic burden for families and society is high, especially in poorly resourced settings. The risk factors for stroke in children differ from the adult population where lifestyle factors play a more important role. The developmental aspects of the pediatric cerebral vasculature and hematological maturational biology affects the clinical presentation, investigation, management and outcomes of childhood stroke in a different way compared to adults. The management of childhood stroke is currently based on expert guidelines and evidence extrapolated from adult studies. Hyperacute therapies that have revolutionized the treatment of stroke in adults cannot be easily applied to children at this stage due to the diagnostic delays, diverse risk factors and developmental considerations mentioned above. Much has been achieved in the understanding of genetic, acquired, preventable and recurrent stroke risk factors in the past decade through international collaborative efforts like the International Pediatric Stroke Study. Evidence for the prevention and treatment of childhood stroke remains elusive. Even more elusive are relevant and achievable management guidelines for pediatric stroke in resource-limited settings. This narrative review focusses on the current management practices globally, emphasizing the challenges, and gaps in knowledge of pediatric stroke in low- and middle-income countries and other areas with limited resources. Priorities and some potential solutions at national and local level are suggested for these settings.

Epilepsy research in Africa: A scoping review by the ILAE Pediatric Commission Research Advocacy Task Force.

OBJECTIVE: Despite the high prevalence of epilepsy in Africa, evaluation of epilepsy research trends on the continent is lacking. Without establishing effective research, improvement in care for people with epilepsy cannot be effectively strategized or targeted. METHODS: A scoping review of the peer-reviewed literature on epilepsy from Africa (1989-2019) was conducted. The aim was to understand from this what areas are well researched versus underresearched based on published epilepsy topics. RESULTS: A total of 1227 publications were identified and assessed. A significant increase in publications occurred over the 30 years assessed. African author leadership was evident in most reports. Nine countries had >50 publications identified; the remaining 45 countries had <50 or no publications. Research studies were typically of lower quality (case series and observational studies). Research themes were more focused on clinical epilepsy (descriptive observational studies) and social aspects (qualitative surveys). However, there were a number of unique and strong themes, specifically for neurocysticercosis and nodding syndrome, where strong research collaborations were evident, basic science understandings were explored, and interventional models were established. SIGNIFICANCE: Despite Africa being the continent with the most countries, it is lacking in the quantity, quality, and for some areas, relevance of research on epilepsy. Targeted approaches are needed to upskill the strength of research undertaken with more basic science, interventional, and randomized controlled studies. Themes of research need to promote those with unique African content but also to align with current international research areas that have impact on care delivery, such as epilepsy surgery and epilepsy genetics. For this to be possible, it is important to strengthen research hubs with collaborations that empower Africa to own its epilepsy research journey.

Barriers to generic antiseizure medication use: Results of a global survey by the International League Against Epilepsy Generic Substitution Task Force.

The objective of this study was to identify and quantify barriers to generic substitution of antiseizure medications (ASM). A questionnaire on generic ASM substitution was developed by the International League Against Epilepsy (ILAE) Task Force on Generic Substitution. Questions addressed understanding of bioequivalence, standards for generic products, experiences with substitution, and demographic data. The survey was web-based and distributed to ILAE chapters, their membership, and professional colleagues of task force members. Comparisons in responses were between ILAE regions and country income classification. A total of 800 individuals responded, with 44.2% being from the Asia-Oceania ILAE Region and 38.6% from European Region. The majority of respondents had little or no education in generic substitution or bioequivalence. Many respondents indicated lack of understanding aspects of generic substitution. Common barriers to generic substitution included limited access, poor or inconsistent quality, too expensive, or lack of regulatory control. Increase in seizures was the most common reported adverse outcome of substitution. Of medications on the World Health Organization Essential Medication list, problems with generic products were most frequent with carbamazepine, lamotrigine, and valproic acid. Several barriers with generic substitution of ASM revolved around mistrust of regulatory control and quality of generic ASM. Lack of education on generic substitution is also a concern. Generic ASM products may be the only option in some parts of the world and efforts should address these issues. Efforts to address these barriers should improve access to medications in all parts of the world.

'There is family tension, but they understand ': familial and sibling relationships following the diagnosis of cerebral palsy in children in Ghana.

The challenges faced by parents raising children with cerebral palsy (CP) have been well explored in the literature. However, little attention has been paid to the experiences of parents raising children with CP in low-income countries, such as Ghana. OBJECTIVE: Therefore, the objective of this study was to explore parents' experiences of raising children with CP, specifically focusing on the relationships between spouses and between children with CP and their typically developing siblings. METHOD: Qualitative semi-structured interviews were conducted with 40 parents, who were purposively selected from the largest tertiary hospital in Ghana. RESULTS: The results revealed that typically developing children accept their siblings with CP as their equals and even take up domestic responsibilities to lessen the burden on their parents. However, the parents reported experiencing marital and extended family conflict, financial burden and negative attitudes from spouses, resulting in family tensions. CONCLUSION: The implications of these findings for policy-making have also been discussed.

The use of assistive technologies among children with disabilities: the perception of parents of children with disabilities in Ghana.

PURPOSE: Assistive technologies (ATs) are fundamental to the successful educational and societal inclusion of all children with disabilities. In particular, the use of ATs has been found to increase levels of independence in daily living and promote greater access to learning opportunities for children with disabilities. However, the knowledge base and baseline information on the use of ATs is limited in developing countries such as Ghana. In this study, we sought to explore the experiences of parents regarding the use of ATs by their children with disabilities in Ghana. MATERIALS AND METHODS: We used a survey questionnaire consisting of both open- and closed-ended questions to explore the perspectives of parents with children with disabilities (n = 35) who were attending the rehabilitation unit of a referral hospital. RESULTS: Although participants acknowledged the benefits of ATs for the development and participation of their children in society, they noted barriers to the usage of ATs by their children. Among several barriers, parents mentioned that they lacked funds to purchase assistive devices. Some parents also mentioned the high cost of ATs and rehabilitation services. CONCLUSION: The need for government to include rehabilitation services and ATs in the National Health Insurance Scheme to ease the burden on participants and other implications of the findings for policymaking are extensively discussed. Implications for rehabilitationIn an environment where there is negative attitude towards children and parents with disabilities, ATs are expected to encourage the participation and acceptance in society.Although many participants were aware of the benefits of ATs to their children, they reported barriers to usage among their children with disabilities.This study shows that poverty, limited health facilities, unfriendly environment and stigmatisation were barriers encountered by parents.We conclude that the government should expand health and rehabilitation facilities to encourage access and participation.

Clinical Characteristics and Morbidity Associated With Coronavirus Disease 2019 in a Series of Patients in Metropolitan Detroit.

Importance: In late December 2019, an outbreak caused by a novel severe acute respiratory syndrome coronavirus 2 emerged in Wuhan, China. Data on the clinical characteristics and outcomes of infected patients in urban communities in the US are limited. Objectives: To describe the clinical characteristics and outcomes of patients with coronavirus disease 2019 (COVID-19) and to perform a comparative analysis of hospitalized and ambulatory patient populations. Design, Setting, and Participants: This study is a case series of 463 consecutive patients with COVID-19 evaluated at Henry Ford Health System in metropolitan Detroit, Michigan, from March 9 to March 27, 2020. Data analysis was performed from March to April 2020. Exposure: Laboratory-confirmed severe acute respiratory syndrome coronavirus 2 infection. Main Outcomes and Measures: Demographic data, underlying comorbidities, clinical presentation, complications, treatment, and outcomes were collected. Results: Of 463 patients with COVID-19 (mean [SD] age, 57.5 [16.8] years), 259 (55.9%) were female, and 334 (72.1%) were African American. Most patients (435 [94.0%]) had at least 1 comorbidity, including hypertension (295 patients [63.7%]), chronic kidney disease (182 patients [39.3%]), and diabetes (178 patients [38.4%]). Common symptoms at presentation were cough (347 patients [74.9%]), fever (315 patients [68.0%]), and dyspnea (282 patients [60.9%]). Three hundred fifty-five patients (76.7%) were hospitalized; 141 (39.7%) required intensive care unit management and 114 (80.8%) of those patients required invasive mechanical ventilation. Male sex (odds ratio [OR], 2.0; 95% CI, 1.3-3.2; P = .001), severe obesity (OR, 2.0; 95% CI, 1.4-3.6; P = .02), and chronic kidney disease (OR, 2.0; 95% CI, 1.3-3.3; P = .006) were independently associated with intensive care unit admission. Patients admitted to the intensive care unit had longer length of stay and higher incidence of respiratory failure and acute respiratory distress syndrome requiring invasive mechanical ventilation, acute kidney injury requiring dialysis, shock, and mortality (57 patients [40.4%] vs 15 patients [7.0%]) compared with patients in the general practice unit. Twenty-nine (11.2%) of those discharged from the hospital were readmitted and, overall, 20.0% died within 30 days. Male sex (OR, 1.8; 95% CI, 1.1-3.1; P = .03) and age older than 60 years (OR, 5.3; 95% CI, 2.9-9.7; P < .001) were significantly associated with mortality, whereas African American race was not (OR, 0.98; 95% CI, 0.54-1.8; P = .86). Conclusions and Relevance: In this review of urban metropolitan patients with COVID-19, most were African American with a high prevalence of comorbid conditions and high rates of hospitalization, intensive care unit admission, complications, and mortality due to COVID-19.

Experiences of primary caregivers of children with cerebral palsy across the trajectory of diagnoses in Ghana.

BACKGROUND: Cerebral palsy (CP) is a non-progressive disorder of posture or movement caused by a lesion to the developing brain that results in functional limitations. The diagnosis of CP can vary from one child to another, causing family stress because of vague and unknown outcomes of the disorder. Although there are negative attitudes in Ghanaian societies towards primary caregivers and children with disabilities, fewer attempts have been made to understand their experiences. OBJECTIVES: The main aim of this study was to explore the experiences of primary caregivers across the trajectory of the diagnosis (before, during and after) of CP in the setting of a tertiary hospital. METHOD: Using Social Capital Theory as framework, 40 primary caregivers of children with CP, who were receiving treatment at a major referral hospital in Ghana, were interviewed about their experiences before, during and after diagnosis. RESULTS: The results that emerged from the thematic analysis were discussed as follows: experiences before diagnosis, experiences during the diagnosis and experiences after the diagnosis. Particularly, participants discussed their inability to access essential services such as education for their children with CP. CONCLUSION: In light of systemic challenges faced by participants and their children with CP, the need for health policymakers to prioritise the public education about CP, promoting the well-being of caregivers and other implications of the study have been discussed.

Neuropsychiatric and Neurocognitive Manifestations in HIV-Infected Children Treated With Efavirenz in South Africa-A Retrospective Case Series.

Background: Efavirenz is associated with transient neuropsychiatric manifestations but the impact on neurocognition in children is unknown. Genetically slow metabolizers of efavirenz may be at risk of toxicity. This study describes neuropsychiatric and neurocognitive manifestations of South African children with suspected efavirenz neurotoxicity. Method: This retrospective study describes clinical features of 12 children with features consistent with efavirenz neurotoxicity between 2008 and 2014. Results: Twelve children (4 males, 8 females) aged 3-12 years (median 8.4 years) were referred to a dedicated pediatric neuroHIV service. Eight were of indigenous African (black) ancestry and 4 were of mixed ancestry. The total duration on efavirenz-containing ART at the time of referral was 6-72 (mean 31) months. Two children (both of black ancestry) were phenotypically slow metabolizers and presented with acute manifestations and high plasma efavirenz concentrations above normal range resulting in discontinuation of efavirenz. Ten other children had clinical presentations compatible with efavirenz neurotoxicity but had normal or sub-therapeutic plasma efavirenz concentrations and continued treatment with efavirenz. The acute neuropsychiatric manifestations reported included drowsiness, seizures, sleep disturbances, personality changes, ataxia, and slurred speech. These were noticed 2-8 weeks (mean 5 weeks) after commencing efavirenz and resolved over a few weeks. Nine children had neurocognitive deficits and showed poor performance in all neurocognitive domains that were tested. Interpretation: Efavirenz causes transient neuropsychiatric adverse effects and may contribute to poor long-term neurocognitive outcomes in HIV-infected children. Prospective studies comparing efavirenz-treated and efavirenz-naïve children are needed to further elucidate the manifestations of efavirenz toxicity.

NeuroAIDS in children.

The human immunodeficiency virus-1 (HIV-1) enters the central nervous system compartment within the first few weeks of systemic HIV infection and may cause a spectrum of neurologic complications. Without combination antiretroviral therapy (cART), 50-90% of all HIV-infected infants and children develop some form of neuroAIDS. Of the estimated 2.3 million children less than 15 years of age who were living in sub-Saharan Africa at the end of 2014, only 30% were receiving cART, suggesting that there is a large burden of neuroAIDS among HIV-infected children in sub-Saharan Africa. There is complex interplay between the disease process itself, the child's immune reaction to the disease, the secondary complications, the side-effects of antiretroviral drugs, and inadequate antiretroviral drug uptake into the central nervous system. In addition there is the layering effect from the multiple socioeconomic challenges for children living in low- and middle-income countries. Adolescents may manifest with a range of neurocognitive sequelae from mild neurocognitive disorder through to severe neurocognitive impairment. Neuroimaging studies on white-matter tracts have identified dysfunction, especially in the frontostriatal networks needed for executive function. Psychiatric symptoms of depression, attention deficit hyperactivity disorder, and behavioral problems are also commonly reported in this age group. Antiretroviral drugs may cause treatment-limiting neurologic and neuropsychiatric adverse reactions. The following chapter addresses the neurologic complications known to be, and suspected of being, associated with HIV infection in children and adolescents.

Assessment of prison life of persons with disability in Ghana.

BACKGROUND: Persons with Disabilities (PWDs) are a unique group that are often overlooked in many developing countries due to systemic weaknesses, lack of political commitment and inadequate support from government and non-governmental agencies. The population of these individuals is however steadily on the increase and currently corresponds to 15 % of the world population. Although much data exist on lifestyle and conditions of prisoners with disabilities in the western world, scanty information is available in Africa. In Ghana, there is insufficient data on the occurrence and social characteristics of prisoners with disabilities. The purpose of this current study was therefore to identify the occurrence, types and causes of disabilities among prisoners serving sentences in Ghanaian prisons. METHODS: This study was a descriptive cross-sectional survey conducted in the Male and Female Regional Prisons in Kumasi, Sunyani and the Nsawam Medium Security Prison, from November to December 2011. PWDs were selected by prisons officers and interviewed using structured questionnaires on variables such as socio-demographic characteristics, causes of disabilities and accessibility to recreational facilities. Ethical approval was obtained from the security services and the Committee of Human Research Publications and Ethics (CHRPE) of the School of Medical Sciences, Kwame Nkrumah University of Science and Technology (KNUST). RESULTS: We screened 6114 records of prisoners of which 1852 (30.3 %) were from the Kumasi Central Prisons, 3483 (57 %) from the Nsawam Medium Security and 779 (12.8 %) from the Sunyani Central Prisons. A total of 99 PWDs were identified with the commonest disability being physical, followed by visual, hearing, speech, mental and albinism. Most of the disabilities were caused by trauma (68.8 %) followed by infection (16.7 %), and drug related mental disabilities (6.3 %). Fifty (50.5 %) out of the 99 PWDs were not provided with assistive devices although they admitted the need for such. CONCLUSION: The present study has demonstrated the occurrence and conditions of PWDs in Ghanaian prisons. Major stakeholders including government agencies and other organisations could develop policies that would improve the conditions and livelihood of prisoners with disabilities in Ghana.

Moyamoya Syndrome in South African Children With HIV-1 Infection.

A national multicenter study identified 17 South African children with vertically acquired HIV-1 infection and HIV-associated vasculopathy. Five of the children (all indigenous African ancestry) had progressive vascular disease, consistent with moyamoya syndrome. Median presentation age 5.8 years (range 2.2-11). The children with moyamoya syndrome presented with abnormal CD4 counts and raised viral loads. Clinical features included motor deficits, neuroregression, and intellectual disability. Neuroimaging supported progressive vascular disease with preceding clinically silent disease course. Neurologic recovery occurred in 1 patient with improved CD4 counts. Four of the 5 children presented during the era when access to antiretroviral therapy was limited, suggesting that with improved management of HIV-1, progressive vasculopathy is less prevalent. However the insidious disease course illustrated indicates that the syndrome can progress "silently," and manifest with misleading phenotypes such as cognitive delay or regression. Sub-Saharan Africa has limited access to neuroimaging and affected children may be underdiagnosed.

Cerebrovascular disease in children with HIV-1 infection.

An estimated 3.2 million children worldwide have human immunodeficiency virus (HIV) infection. Antiretroviral therapy (ART) has resulted in prolonged survival, leading to an increase in complications previously recognized in adults. Children with HIV infection have increased risk of cerebrovascular disease from multiple aetiologies including HIV-associated vasculopathy, opportunistic vasculitis, cardioembolism or coagulopathy, all of which may be secondary to the infection. Prevalence of cerebrovascular disease in HIV-infected children is underestimated because of limited neuroimaging in low and middle income countries, silent events without overt motor manifestations, and mislabeling as HIV encephalopathy for non-motor manifestations such as behavioural and cognitive difficulties. No management guidelines for cerebrovascular disease in HIV-infected children exist but common practices target risk factors for stroke in low and middle income countries. Where capacity permits, screening for opportunistic infections, vasculitis, coagulopathy and cardioembolism is important. Optimising virological suppression, correction of anaemia, control of seizures and aspirin prophylaxis are management priorities. Neurosurgical interventions may have a role.

A Polymer-Based Antibody-Vinca Drug Conjugate Platform: Characterization and Preclinical Efficacy.

Antibody-drug conjugates (ADC) are an emerging drug class that uses antibodies to improve cytotoxic drug targeting for cancer treatment. ADCs in current clinical trials achieve a compromise between potency and physicochemical/pharmacokinetic properties by conjugating potent cytotoxins directly to an antibody at a 4:1 or less stoichiometric ratio. Herein, we report a novel, polyacetal polymer-based platform for creating ADC that use poly-1-hydroxymethylethylene hydroxymethyl-formal (PHF), also known as Fleximer. The high hydrophilicity and polyvalency properties of the Fleximer polymer can be used to produce ADC with high drug loading without compromising physicochemical and pharmacokinetic properties. Using trastuzumab and a vinca drug derivative to demonstrate the utility of this platform, a novel Fleximer-based ADC was prepared and characterized in vivo. The ADC prepared had a vinca-antibody ratio of 20:1. It exhibited a high antigen-binding affinity, an excellent pharmacokinetic profile and antigen-dependent efficacy, and tumor accumulation in multiple tumor xenograft models. Our findings illustrate the robust utility of the Fleximer platform as a highly differentiated alternative to the conjugation platforms used to create ADC currently in clinical development.

Helicobacter pylori virulence factors affecting gastric proton pump expression and acid secretion.

Acute Helicobacter pylori infection of gastric epithelial cells and human gastric biopsies represses H,K-ATPase α subunit (HKα) gene expression and inhibits acid secretion, causing transient hypochlorhydria and supporting gastric H. pylori colonization. Infection by H. pylori strains deficient in the cag pathogenicity island (cag PAI) genes cagL, cagE, or cagM, which do not transfer CagA into host cells or induce interleukin-8 secretion, does not inhibit HKα expression, nor does a cagA-deficient strain that induces IL-8. To test the hypothesis that virulence factors other than those mediating CagA translocation or IL-8 induction participate in HKα repression by activating NF-κB, AGS cells transfected with HKα promoter-Luc reporter constructs containing an intact or mutated NF-κB binding site were infected with wild-type H. pylori strain 7.13, isogenic mutants lacking cag PAI genes responsible for CagA translocation and/or IL-8 induction (cagA, cagζ, cagε, cagZ, and cagß), or deficient in genes encoding two peptidoglycan hydrolases (slt and cagγ). H. pylori-induced AGS cell HKα promoter activities, translocated CagA, and IL-8 secretion were measured by luminometry, immunoblotting, and ELISA, respectively. Human gastric biopsy acid secretion was measured by microphysiometry. Taken together, the data showed that HKα repression is independent of IL-8 expression, and that CagA translocation together with H. pylori transglycosylases encoded by slt and cagγ participate in NF-κB-dependent HKα repression and acid inhibition. The findings are significant because H. pylori factors other than CagA and IL-8 secretion are now implicated in transient hypochlorhydria which facilitates gastric colonization and potential triggering of epithelial progression to neoplasia.

Discrimination of normal and esophageal cancer plasma proteomes by MALDI-TOF mass spectrometry.

BACKGROUND: Most patients presenting with symptoms of esophageal cancer (EC) have advanced disease. Even with resection, the cure rate is extremely low due to local recurrence and metastatic disease. Early detection and effective therapeutic intervention are essential to improve survival. AIMS: This study tested the hypothesis that the presence of EC modulates concentrations of specific plasma proteins and peptides, potentially allowing discrimination between EC and controls based on mass spectrometric analysis of the respective plasma proteomes. METHODS: Blood samples from 79 esophageal cancer patients and 40 age-matched normal subjects were processed to plasma, and protein/peptide sub-fractions were isolated using HIC8 or WAX-derivatized superparamagnetic beads. Triplicate matrix-assisted laser desorption time-of-flight mass spectra were acquired for specific plasma fractions from each subject. RESULTS: HIC8 and WAX-derivatized plasma eluates yielded 79 and 77 candidate features, respectively, and a Random Forest algorithm identified a subset of features whose peak intensities allowed discrimination between cancer patients and controls. Areas under the curve in receiver operating characteristic curves for HIC8 spectra were 0.88 and 0.83 for WAX spectra. The combined feature set discriminated EC from control plasma with 79 % sensitivity and 79 % specificity, with positive and negative test likelihood ratios of >14 and 0.17, respectively. CONCLUSIONS: These data lay the foundation for the development of a clinically useful test for esophageal cancer based on statistical analysis of proteomic spectra of patient plasma samples. This approach will be validated by analysis of larger patient cohorts, development of cancer-specific classifiers, and assessment of racial origin imbalances.

Helicobacter pylori-induced posttranscriptional regulation of H-K-ATPase α-subunit gene expression by miRNA.

Acute Helicobacter pylori infection of gastric epithelial cells induces CagA oncoprotein- and peptidoglycan (SLT)-dependent mobilization of NF-κB p50 homodimers that bind to H-K-ATPase α-subunit (HKα) promoter and repress HKα gene transcription. This process may facilitate gastric H. pylori colonization by induction of transient hypochlorhydria. We hypothesized that H. pylori also regulates HKα expression posttranscriptionally by miRNA interaction with HKα mRNA. In silico analysis of the HKα 3' untranslated region (UTR) identified miR-1289 as a highly conserved putative HKα-regulatory miRNA. H. pylori infection of AGS cells transfected with HKα 3' UTR-Luc reporter construct repressed luciferase activity by 70%, whereas ΔcagA or Δslt H. pylori infections partially abrogated repression. Transfection of AGS cells expressing HKα 3' UTR-Luc construct with an oligoribonucleotide mimetic of miR-1289 induced maximal repression (54%) of UTR activity within 30 min; UTR activity was unchanged by nontargeting siRNA transfection. Gastric biopsies from patients infected with cagA(+) H. pylori showed a significant increase in miR-1289 expression compared with uninfected patients or those infected with cagA(-) H. pylori. Finally, miR-1289 expression was necessary and sufficient to attenuate biopsy HKα protein expression in the absence of infection. Taken together, these data indicate that miR-1289 is upregulated by H. pylori in a CagA- and SLT-dependent manner and targets HKα 3' UTR, affecting HKα mRNA translation. The sensitivity of HKα mRNA 3' UTR to binding of miR-1289 identifies a novel regulatory mechanism of gastric acid secretion and offers new insights into mechanisms underlying transient H. pylori-induced hypochlorhydria.