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1.
BMJ Open ; 13(11): e075817, 2023 11 27.
Article in English | MEDLINE | ID: mdl-38011972

ABSTRACT

INTRODUCTION: Child mortality rates remain high in sub-Saharan Africa, including Ethiopia. We are conducting a cluster randomised control trial in the Gondar zone of the Amhara region to determine the impact of pairing Orthodox priests with community health workers, known locally as the Health Development Army (HDA), on newborns' nutritional status, early illness identification and treatment, and vaccination completeness.Ensuring intervention efficacy with scientific rigour is essential, but there are often delays in adopting evidence into policy and programmes. Here, we present a protocol for conducting parallel implementation research alongside an efficacy study to understand intervention implementability and scalability. This will help develop a scale-up strategy for effective elements of the intervention to ensure rapid implementation at scale. METHODS AND ANALYSIS: We will conduct a stakeholder analysis of key implementation stakeholders and readiness surveys to assess their readiness to scale up the intervention. We will conduct semistructured interviews and focus group discussions with stakeholders, including HDA members, health workers, Orthodox priests, and caregivers, to determine the core intervention elements that need to be scaled, barriers and facilitators to scaling up the intervention in diverse sociocultural settings, as well as the human and technical requirements for national and regional implementation. Finally, to determine the financial resources necessary for sustaining and scaling the intervention, we will conduct activity-based costing to estimate implementation costs from the provider's perspective. ETHICS AND DISSEMINATION: The study received approval from the University of Gondar Institutional Review Board (approval no: VP/RTT/05/1030/2022) and the University of Washington Human Subjects Division (approval no: STUDY00015369). Participants will consent to participate. Results will be disseminated through workshops with stakeholders, local community meetings, presentations at local and international conferences, and journal publications. The study will provide evidence for factors to consider in developing a scale-up strategy to integrate the intervention into routine health system practices.


Subject(s)
Implementation Science , Public Health , Child , Humans , Infant , Infant, Newborn , Ethiopia , Nutritional Status , Outcome Assessment, Health Care , Randomized Controlled Trials as Topic
2.
J Glob Health ; 11: 04063, 2021.
Article in English | MEDLINE | ID: mdl-34737863

ABSTRACT

BACKGROUND: Ethiopia and other countries continue to experience high rates of maternal mortality and neonatal deaths. Interventions are needed to increase utilization of antenatal care (ANC) and facility delivery services to improve outcomes. METHODS: A cluster-randomized trial was conducted in the Amhara Region of Ethiopia, with 6 communities randomly assigned to receive the intervention and 12 communities monitored as controls. Intervention teams provided outreach to pregnant women and their families. Registry data were used to measure utilization of services provided at health centers in intervention and control communities.The intervention consisted of trained pairs of community health workers and Ethiopian Orthodox priests who worked together to promote health messages around safe delivery. The pairs visited pregnant women and their families in their homes to provide counseling, discuss concerns, and answer questions about ANC and facility deliveries. Intervention impact was measured using facility-level data on monthly number of ANC visits and facility deliveries at the health centers that served the intervention and control communities. Intervention effect was measured using difference-in-difference analyses estimated by generalized estimating equation models. RESULTS: During the 12-month intervention period, intervention facilities (n = 6) recorded 14% more ANC1 visits (relative risk RR = 1.14; 95% confidence interval (CI) = 1.09-1.19; P < 0.001) and 26% more ANC4 visits (RR = 1.26; 95%CI = 1.18, 1.34; P < 0.001) compared to control health centers (n = 12). The intervention health centers experienced a 10% increase in facility deliveries over what would have been expected had the intervention not occurred (RR = 1.10; 95% CI = 1.05-1.16; P < 0.001). CONCLUSIONS: Promotion of safe delivery through home visits by community health workers paired with Ethiopian Orthodox priests increased utilization of ANC and facility delivery services. This approach could leverage the influential role of faith leaders and increase the impact of community health workers in Ethiopia. TRIAL REGISTRATION: NCT04039932.


Subject(s)
Community Health Workers , Prenatal Care , Ethiopia , Female , Health Promotion , Humans , Infant, Newborn , Maternal Mortality , Pregnancy
3.
S Afr Med J ; 107(12): 1058-1064, 2017 Nov 27.
Article in English | MEDLINE | ID: mdl-29262956

ABSTRACT

BACKGROUND: Many people living with HIV in South Africa (SA) are not aware of their seropositive status and are diagnosed late during the course of HIV infection. These individuals do not obtain the full benefit from available HIV care and treatment services. OBJECTIVES: To describe the prevalence of late presentation for HIV care among newly diagnosed HIV-positive individuals and evaluate sociodemographic variables associated with late presentation for HIV care in three high-burden districts of SA. METHODS: We used data abstracted from records of 8 138 newly diagnosed HIV-positive individuals in 35 clinics between 1 June 2014 and 31 March 2015 to determine the prevalence of late presentation among newly diagnosed HIV-positive individuals in selected high-prevalence health districts. Individuals were categorised as 'moderately late', 'very late' or 'extremely late' presenters based on specified criteria. Descriptive analysis was performed to measure the prevalence of late presentation, and multivariate regression analysis was conducted to identify variables independently associated with extremely late presentation. RESULTS: Overall, 79% of the newly diagnosed cases presented for HIV care late in the course of HIV infection (CD4+ count ≤500 cells/µL and/or AIDS-defining illness in World Health Organization (WHO) stage III/IV), 19% presented moderately late (CD4+ count 351 - 500 cells/µL and WHO clinical stage I or II), 27% presented very late (CD4+ count 201 - 350 cells/µL or WHO clinical stage III), and 33% presented extremely late (CD4+ count ≤200 cells/µL and/or WHO clinical stage IV) for HIV care. Multivariate regression analysis indicated that males, non-pregnant women, individuals aged >30 years, and those accessing care in facilities located in townships and inner cities were more likely to present late for HIV care. CONCLUSIONS: The majority of newly diagnosed HIV-positive individuals in the three high-burden districts (Gert Sibande, uThukela and City of Johannesburg) presented for HIV care late in the course of HIV infection. Interventions that encourage early presentation for HIV care should be prioritised in SA and should target males, non-pregnant women, individuals aged >30 years and those accessing care in facilities located in inner cities and urban townships.


Subject(s)
Delayed Diagnosis , Early Diagnosis , HIV Infections , Health Services Accessibility , Healthcare Disparities/statistics & numerical data , Adult , Age Factors , CD4 Lymphocyte Count/methods , Delayed Diagnosis/prevention & control , Delayed Diagnosis/statistics & numerical data , Early Medical Intervention/organization & administration , Female , HIV Infections/diagnosis , HIV Infections/epidemiology , Health Services Accessibility/organization & administration , Health Services Accessibility/statistics & numerical data , Humans , Male , Needs Assessment , Prevalence , Risk Factors , Sex Factors , South Africa/epidemiology , Time Factors
5.
J Fish Biol ; 81(2): 750-65, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22803734

ABSTRACT

The reproductive biology of the only known intact species flock of large cyprinids, the 16 Labeobarbus species of Lake Tana (Ethiopia), has been extensively studied for the past two decades. Seven species of Labeobarbus are known to migrate >50 km upstream into tributary rivers for spawning during the rainy season (July to October), whereas eight other species are absent from these rivers and probably developed a new strategy of lacustrine spawning (macro-spatial segregation). One species (L. intermedius) probably spawns in the lake as well as in the rivers. Between the early 1990s and 2000s, the riverine spawners showed a decline of 75% in both biomass and number in both fishery independent surveys and in commercial catches. Reproductive migration makes fishes vulnerable to fisheries and other threats like habitat modifications. Lacustrine spawners are probably more resilient as they are not known to form spawning aggregations that can easily be exploited by fishermen. In addition, upstream rivers and catchments around Lake Tana are highly degraded by erosion and recently subjected to intensive habitat modification for irrigation and hydroelectric power generation. This article reviews results of field studies on the Labeobarbus spawning migration from Lake Tana to spawning rivers, giving emphasis on segregation and homing. It also summarizes existing and emerging threats which form potential causes for the decline of the migratory Labeobarbus species. Knowledge gaps on the reproductive biology are identified for further investigation.


Subject(s)
Animal Migration , Conservation of Natural Resources , Cyprinidae/physiology , Animals , Cues , Ethiopia , Homing Behavior , Lakes , Reproduction , Rivers
6.
Scand J Immunol ; 70(3): 277-87, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19703017

ABSTRACT

Immunoglobulin (IgG) has the ability to suppress the Ab response against the Ag to which it binds. Although the mechanism remains unclear, this phenomenon has physiological relevance and is used clinically in Rh prophylaxis. As suppression works well in mice lacking the inhibitory FcgammaRIIB, the two most likely explanations are that IgG masks epitopes and/or that IgG increases the clearance of Ag. In the present study, mice were immunized with sheep red blood cells (SRBC) to which the hapten 5-iodo-4-hydroxyl-3-nitrophenacetyl (NIP) was conjugated at high or low density and the ability of IgG anti-NIP to suppress the Ab response to NIP and SRBC was assayed. Only the NIP-specific response was suppressed when mice were immunized with SRBC-NIP(low), whereas both NIP- and SRBC-specific responses were suppressed when SRBC-NIP(high) was used. This is best explained by epitope masking; at high epitope density, IgG also blocks neighbouring epitopes from recognition by B cells. We also examined the effects of IgG-mediated suppression on T-cell responses directly in vivo. While IgG anti-SRBC administered with sheep red blood cells ovalbumin (SRBC-OVA) almost completely suppressed the anti-SRBC and anti-OVA Ab responses, the OVA-specific T-cell response was still 50% of that observed in control mice. This is probably the result of decreased Ag exposure as IgG-bound SRBC were cleared faster from the bloodstream and were found at lower concentration in the spleen than unbound SRBC. These results suggest that both Ag clearance and epitope masking occurs during IgG-mediated suppression, but that under physiological circumstances epitope masking is the predominant mechanism.


Subject(s)
Antibody Formation , Antigens/immunology , Epitopes/immunology , Immunoglobulin G/immunology , Nitrohydroxyiodophenylacetate/immunology , Spleen/immunology , Adoptive Transfer , Animals , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/metabolism , Epitopes/metabolism , Erythrocytes/immunology , Immunoglobulin G/metabolism , Mice , Mice, Inbred BALB C , Nitrohydroxyiodophenylacetate/metabolism , Sheep , Spleen/metabolism
7.
Scand J Immunol ; 70(2): 77-84, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19630912

ABSTRACT

Severely impaired Ab responses are seen in animals lacking C (complement) factors C2, C3 or C4 as well as CR1/2 (C receptors 1 and 2). The molecular mechanism behind this phenomenon is not understood. One possibility is that C-containing immune complexes are endocytosed via CR2 on B cells and presented to specific CD4+ T cells, which would then proliferate and provide efficient help to specific B cells. In vitro, B cells can endocytose immune complexes via CR1/2 and present the Ag to T cells. Whether absence of this Ag presenting function in Cr2(-/-) mice (mice lacking CR1/2) explains their low Ab response is unclear. To address this question, Cr2(-/-) and wild type mice were transferred with OVA-specific T cells, obtained from the DO11.10 strain which has a transgenic TCR recognizing an OVA peptide. The animals were subsequently immunized with sheep red blood cells (SRBC) conjugated to OVA. Interestingly, proliferation of the OVA-specific T cells was normal in Cr2(-/-) mice, although their Ab response to both SRBC and OVA was severely impaired. These observations suggest that the impaired Ab response in Cr2(-/-) mice cannot be explained by a lack of appropriate induction of T cell help.


Subject(s)
Antibody Formation/immunology , B-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/immunology , Receptors, Complement 3d/immunology , Receptors, Complement/immunology , Adoptive Transfer , Animals , Antibody Formation/genetics , B-Lymphocytes/metabolism , CD4-Positive T-Lymphocytes/metabolism , Mice , Mice, Inbred BALB C , Mice, Knockout , Mice, Transgenic , Ovalbumin/immunology , Receptors, Complement/genetics , Receptors, Complement 3d/genetics
8.
Scand J Immunol ; 64(3): 177-84, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16918684

ABSTRACT

Antibodies administered in vivo together with the antigen they are specific for can regulate the immune response to that antigen. This phenomenon is called antibody-mediated feedback regulation and has been known for over 100 years. Both passively administered and actively produced antibodies exert immunoregulatory functions. Feedback regulation can be either positive or negative, resulting in >1000-fold enhancement or >99% suppression of the specific antibody response. Usually, the response to the entire antigen is up- or downregulated, regardless of which epitope the regulating antibody recognizes. IgG of all isotypes can suppress responses to large particulate antigens like erythrocytes, a phenomenon used clinically in Rhesus prophylaxis. IgG suppression works in mice lacking the known Fc-gamma receptors (FcgammaR) and a likely mechanism of action is epitope masking. IgG1, IgG2a and IgG2b administered together with soluble protein antigens will enhance antibody and CD4+ T-cell responses via activating FcgammaR, probably via increased antigen presentation by dendritic cells. IgG3 as well as IgM also enhance antibody responses but their effects are dependent on their ability to activate complement. A possible mechanism is increased B-cell activation caused by immune complexes co-crosslinking the B-cell receptor with the complement-receptor 2/CD19 receptor complex, known to lower the threshold for B-cell activation. IgE-antibodies enhance antibody and CD4+ T-cell responses to small soluble proteins. This effect is entirely dependent on the low-affinity receptor for IgE, CD23, the mechanism probably being increased antigen presentation by CD23+ B cells.


Subject(s)
Antibody Formation , Models, Immunological , Animals , Feedback, Physiological , Humans , Immune Tolerance , Immunoglobulin G/immunology , Immunoglobulin M/immunology
9.
J Immunol ; 167(10): 5558-64, 2001 Nov 15.
Article in English | MEDLINE | ID: mdl-11698426

ABSTRACT

The suppressive effect of IgG on Ab responses to particulate Ags such as erythrocytes is well documented. IgG-mediated suppression is used clinically in rhesus prophylaxis to prevent RhD-negative mothers from becoming immunized against their Rh D-positive fetuses. We have recently shown that IgG anti-SRBC, passively administered together with SRBC, can induce efficient suppression of primary Ab responses to SRBC in mice lacking the known FcRs for IgG (FcgammaRI, FcgammaIII, and FcgammaRIIB or the neonatal FcR). The lack of a demonstrable effect of the inhibitory FcgammaRIIB was particularly surprising, and, in this study, the involvement of this receptor is further investigated during broader experimental conditions. The data show that SRBC-specific IgG administered up to 5 days after SRBC can induce suppression both in wild-type and FcgammaRIIB-deficient mice. Suppression of secondary Ab responses to SRBC in vivo was similar in the two strains. In contrast, IgG-mediated suppression of Ab responses in vitro was impaired in cultures with primed FcgammaRIIB-deficient spleen cells. In conclusion, inhibition of in vivo Ab responses to SRBC by passively administered IgG can take place via an FcgammaRIIB-independent pathway. This pathway causes >99% suppression and operates during all experimental conditions studied so far. The nature of the mechanism can at present only be hypothesized. Masking of epitopes and/or rapid elimination of IgG-Ag complexes would both be compatible with the observations.


Subject(s)
Antigens, CD/physiology , Immunoglobulin G/pharmacology , Immunoglobulins/biosynthesis , Receptors, IgG/physiology , Adoptive Transfer , Animals , Antigens, CD/genetics , B-Lymphocytes/immunology , B-Lymphocytes/transplantation , Cells, Cultured , Erythrocytes/immunology , Hemolytic Plaque Technique , Immunization, Secondary , Kinetics , Mice , Mice, Knockout , Receptors, IgG/genetics , Spleen/immunology
11.
Dev Comp Immunol ; 24(8): 751-63, 2000 Dec.
Article in English | MEDLINE | ID: mdl-10906388

ABSTRACT

In this study the characterisation of the Atlantic salmon (MhcSasa-DAA) and rainbow trout (MhcOnmy-DAA) class II alpha chain cDNA sequences is presented. The DAA sequences from these two salmonid species showed a high degree of similarity, although the Onmy-DAA(*)03 cDNA sequence differed in the cytoplasmic region. Interestingly, the Onmy-DAA(*)02 sequence has lost the second cysteine in the alpha-1 domain. However, another cysteine is present in this sequence 7 positions downstream of the cysteine which is substituted for a leucine. Despite a thorough search, only a single locus of expressed class II alpha chain sequences was identified in both salmonid species. Amplification by PCR and sequencing of the alpha-1 domain from genomic DNA of three Atlantic salmon, identified four different variants assumed to have derived from this single locus. Two of these variants originated from one individual and are likely functional alleles.


Subject(s)
Histocompatibility Antigens Class II/genetics , Salmon/genetics , Amino Acid Sequence , Amino Acid Substitution , Animals , Cysteine , DNA/genetics , DNA, Complementary , Genetic Variation , Molecular Sequence Data , Oncorhynchus mykiss/genetics , Phylogeny , Salmo salar/genetics , Sequence Alignment
12.
Immunology ; 97(3): 408-13, 1999 Jul.
Article in English | MEDLINE | ID: mdl-10447761

ABSTRACT

Immunoglobulin (IgM) is found in various states of covalent polymerization (microL)n, where n is typically 8, 10, or 12. The usual form of IgM of bony fish is tetrameric (8 microL units) as compared to the pentameric form (10 microL units) observed in cartilaginous fish and mammals. Two hypotheses were tested in this study. First, that the length of the mu-chain C terminus following Cys575 determines whether an IgM polymerizes as a tetramer or as a pentamer. This was tested by examining the covalent polymerization state of mouse IgM mutated to contain a series of mu-chain C-termini from bony and cartilaginous fish. The results proved this hypothesis wrong: mouse IgM bearing the C-terminal sequence of shark, salmon and cod mu-chain behaved identically to native mouse IgM, forming predominantly (microL)10 and (microL)12 forms. The second hypothesis was that an additional Cys residue near the C terminus of the mu-chain is responsible for the multiple covalent structures seen in IgM of the channel catfish. The addition of a catfish C terminus to the mouse mu-chain resulted, as predicted, in the production of a series of covalently bonded forms, with the major species being (microL)4. When a Ser-Cys unit was removed from the catfish C terminus added to the mouse mu-chain, this resulted in production of IgM indistinguishable in structure from that of wild-type mouse IgM.


Subject(s)
Fishes/immunology , Immunoglobulin M/chemistry , Immunoglobulin mu-Chains/chemistry , Animals , Catfishes/immunology , Cell Culture Techniques , Cell Line , Culture Techniques , Electrophoresis, Polyacrylamide Gel , Immunoglobulin M/biosynthesis , Immunoglobulin mu-Chains/genetics , Macromolecular Substances , Mice , Polymerase Chain Reaction , Protein Structure, Quaternary , Structure-Activity Relationship
13.
Dev Dyn ; 213(1): 39-49, 1998 Sep.
Article in English | MEDLINE | ID: mdl-9733099

ABSTRACT

The purpose of this study was to make an explicit test of the idea that a retinoid could act as a morphogen, differentially activating genes and specifying anteroposterior (a-p) level in the developing vertebrate central nervous system (CNS). Our approach was to characterize the concentration-dependent effects of retinoic acid (RA) on the neural expression of a set of a-p patterning genes, both in vivo and in an in vitro system for neural patterning. Our results indicate that a retinoid is unlikely to specify a-p level along the entire CNS. Instead, our data support the idea that the developing hindbrain may be patterned by a retinoid gradient. Sequentially more posterior hindbrain patterning genes were induced effectively by sequentially higher RA concentration windows. The most posterior CNS level induced under our RA treatment conditions corresponded to the most posterior part of the hindbrain.


Subject(s)
Rhombencephalon/metabolism , Tretinoin/metabolism , Animals , Gene Expression Regulation, Developmental/drug effects , Homeodomain Proteins/genetics , Models, Biological , Rhombencephalon/drug effects , Rhombencephalon/embryology , Tretinoin/pharmacology , Xenopus
14.
Trop Geogr Med ; 40(3): 233-6, 1988 Jul.
Article in English | MEDLINE | ID: mdl-3188214

ABSTRACT

A house-to-house survey of neonatal tetanus was performed in 30 population clusters in Gondar, Northwestern Ethiopia. At the end of the survey 37,219 households were visited and 2010 live births were recalled. Out of the 2010 live-born children 127 had died. Eighty died during the neonatal period. Nine of the neonatal deaths were due to tetanus, giving a neonatal tetanus mortality rate of 4.5/1000 live births. The problem of neonatal tetanus in developing countries, particularly that of Ethiopia, is discussed.


Subject(s)
Tetanus/epidemiology , Ethiopia , Female , Health Surveys , Home Childbirth , Humans , Infant, Newborn , Retrospective Studies , Rural Health , Tetanus/mortality , Tetanus Toxoid/administration & dosage , Urban Health
15.
Am J Trop Med Hyg ; 38(3): 633-5, 1988 May.
Article in English | MEDLINE | ID: mdl-3275143

ABSTRACT

A house-to-house survey was carried out to determine the prevalence of poliomyelitis. During the survey 37,219 households were visited and 17,941 children 5-9 years old were found. Of 231 lame children, lameness compatible with paralytic poliomyelitis was found in 131, of these 91% had their condition before the age of 3 years. Nineteen percent needed a stick support for walking while 12% were unable to walk even with support. This problem was more common in rural populations. The prevalence of paralytic poliomyelitis was 7.3/1,000 children 5-9 years old.


Subject(s)
Paralysis/epidemiology , Poliomyelitis/epidemiology , Cerebral Palsy/complications , Child , Ethiopia/epidemiology , Humans , Lathyrism/complications , Paralysis/congenital , Paralysis/etiology , Poliomyelitis/complications , Prevalence , Rural Population , Urban Population , Wounds and Injuries/complications
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