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1.
Immunol Rev ; 313(1): 162-180, 2023 01.
Article in English | MEDLINE | ID: mdl-36336911

ABSTRACT

The alternative pathway (AP) is the phylogenetically oldest arm of the complement system and may have evolved to mark pathogens for elimination by phagocytes. Studies using purified AP proteins or AP-specific serum showed that C3b amplification on bacteria commenced following a lag phase of about 5 min and was highly dependent on the concentration of complement. Most pathogens have evolved several elegant mechanisms to evade complement, including expressing proteases that degrade AP proteins and secreting proteins that block function of C3 convertases. In an example of convergent evolution, many microbes recruit the AP inhibitor factor H (FH) using molecular mechanisms that mimic FH interactions with host cells. In most instances, the AP serves to amplify C3b deposited on microbes by the classical pathway (CP). The role of properdin on microbes appears to be restricted to stabilization of C3 convertases; scant evidence exists for its role as an initiator of the AP on pathogens in the context of serum. Therapeutic complement inhibition carries with it an increased risk of infection. Antibody (Ab)-dependent AP activation may be critical for complement activation by vaccine-elicited Ab when the CP is blocked, and its molecular mechanism is discussed.


Subject(s)
Bacterial Infections , Complement Activation , Complement Pathway, Alternative , Humans , Complement Activation/physiology , Properdin/metabolism , Bacterial Infections/metabolism , Complement C3b/metabolism
2.
J Infect Dis ; 226(12): 2192-2203, 2022 12 13.
Article in English | MEDLINE | ID: mdl-36201640

ABSTRACT

BACKGROUND: Likelihood of Neisseria gonorrhoeae infection in women exposed to male sex partners with increasing N. gonorrhoeae burdens and enhancement by Chlamydia trachomatis is not defined. METHODS: We identified men with urethritis and their regular female sex partners. Exposure to N. gonorrhoeae burdens in men was compared in N. gonorrhoeae-infected versus -uninfected partners. Association of N. gonorrhoeae infection in women with burdens in male partners was estimated using logistic regression. Association of C. trachomatis coinfection and N. gonorrhoeae burdens in women adjusted for burdens in male partners was estimated by linear regression. RESULTS: In total, 1816 men were enrolled; 202 had ≥2 partners, 91 who confirmed monogamy and were enrolled; 77% were married. Seventy were partners of N. gonorrhoeae-infected men; 58 (83%) were N. gonorrhoeae infected, 26 (45%) C. trachomatis coinfected. Infected women had partners with 9.3-fold higher N. gonorrhoeae burdens than partners of uninfected women (P = .0041). Association of N. gonorrhoeae infection in women with upper quartiles of N. gonorrhoeae burdens in partners increased (odds ratios ≥ 2.97)compared to the first quartile (P = .032). N. gonorrhoeae burdens in C. trachomatis-coinfected women were 2.82-fold higher than in C. trachomatis-uninfected women (P = .036). CONCLUSIONS: N. gonorrhoeae infections increased in women whose partners were infected with higher N. gonorrhoeae burdens. C. trachomatis coinfection was associated with increased N. gonorrhoeae burdens in women.


Subject(s)
Chlamydia Infections , Coinfection , Gonorrhea , Female , Male , Humans , Gonorrhea/complications , Gonorrhea/epidemiology , Chlamydia Infections/complications , Chlamydia Infections/epidemiology , Coinfection/epidemiology , Coinfection/complications , Chlamydia trachomatis , Neisseria gonorrhoeae
3.
J Infect Dis ; 225(10): 1861-1864, 2022 05 16.
Article in English | MEDLINE | ID: mdl-34971376

ABSTRACT

A safe and effective vaccine against multidrug-resistant gonorrhea is urgently needed. An experimental peptide vaccine called TMCP2 that mimics an oligosaccharide epitope in gonococcal lipooligosaccharide, when adjuvanted with glucopyranosyl lipid adjuvant-stable emulsion, elicits bactericidal immunoglobulin G and hastens clearance of gonococci in the mouse vaginal colonization model. In this study, we show that efficacy of TMCP2 requires an intact terminal complement pathway, evidenced by loss of activity in C9-/- mice or when C7 function was blocked. In conclusion, TMCP2 vaccine efficacy in the mouse vagina requires membrane attack complex. Serum bactericidal activity may serve as a correlate of protection for TMCP2.


Subject(s)
Gonorrhea , Neisseria gonorrhoeae , Animals , Bacterial Vaccines , Complement System Proteins , Disease Models, Animal , Female , Gonorrhea/prevention & control , Lipopolysaccharides , Mice
4.
J Immunol ; 204(12): 3283-3295, 2020 06 15.
Article in English | MEDLINE | ID: mdl-32434942

ABSTRACT

Neisseria gonorrhoeae deploys a unique immune evasion strategy wherein the lacto-N-neotetraose termini of lipooligosaccharide (LOS) are "capped" by a surface LOS sialyltransferase (Lst), using extracellular host-derived CMP-sialic acid (CMP-Neu5Ac in humans). LOS sialylation enhances complement resistance by recruiting factor H (FH; alternative complement pathway inhibitor) and also by limiting classical pathway activation. Sialylated LOS also engages inhibitory Siglecs on host leukocytes, dampening innate immunity. Previously, we showed that analogues of CMP-sialic acids (CMP-nonulosonates [CMP-NulOs]), such as CMP-Leg5,7Ac2 and CMP-Neu5Ac9N3, are also substrates for Lst. Incorporation of Leg5,7Ac2 and Neu5Ac9N3 into LOS results in N. gonorrhoeae being fully serum sensitive. Importantly, intravaginal administration of CMP-Leg5,7Ac2 attenuated N. gonorrhoeae colonization of mouse vaginas. In this study, we characterize and develop additional candidate therapeutic CMP-NulOs. CMP-ketodeoxynonulosonate (CMP-Kdn) and CMP-Kdn7N3, but not CMP-Neu4,5Ac2, were substrates for Lst, further elucidating gonococcal Lst specificity. Lacto-N-neotetraose LOS capped with Kdn and Kdn7N3 bound FH to levels ∼60% of that seen with Neu5Ac and enabled gonococci to resist low (3.3%) but not higher (10%) concentrations of human complement. CMP-Kdn, CMP-Neu5Ac9N3, and CMP-Leg5,7Ac2 administered intravaginally (10 µg/d) to N. gonorrhoeae-colonized mice were equally efficacious. Of the three CMP-NulOs above, CMP-Leg5,7Ac2 was the most pH and temperature stable. In addition, Leg5,7Ac2-fed human cells did not display this NulO on their surface. Moreover, CMP-Leg5,7Ac2 was efficacious against several multidrug-resistant gonococci in mice with a humanized sialome (Cmah-/- mice) or humanized complement system (FH/C4b-binding protein transgenic mice). CMP-Leg5,7Ac2 and CMP-Kdn remain viable leads as topical preventive/therapeutic agents against the global threat of multidrug-resistant N. gonorrhoeae.


Subject(s)
Cytidine Monophosphate N-Acetylneuraminic Acid/pharmacology , Cytidine Monophosphate/analogs & derivatives , Cytidine Monophosphate/physiology , Drug Resistance, Multiple, Bacterial/drug effects , Gonorrhea/drug therapy , Neisseria gonorrhoeae/drug effects , Neuraminic Acids/pharmacology , Sialic Acids/pharmacology , Animals , Cell Line, Tumor , Complement Factor H/metabolism , Complement System Proteins/pharmacology , Cytidine Monophosphate/pharmacology , Female , Gonorrhea/metabolism , Gonorrhea/microbiology , Humans , Lipopolysaccharides/pharmacology , Mice , Mice, Inbred BALB C , Mice, Transgenic , Oligosaccharides/physiology , Sialyltransferases/pharmacology
5.
J Adv Nurs ; 78(4): 918-928, 2022 Apr.
Article in English | MEDLINE | ID: mdl-34910316

ABSTRACT

BACKGROUND: Chronic kidney disease is a common and prevalent condition in the United States. However, 90% of individuals with chronic kidney disease are unaware of their diagnosis. AIMS: To summarize the empirical and theoretical literature to provide a comprehensive understanding of the social determinants of health inequities associated with CKD awareness. Social determinants of health inequities are underlying pathways that shape the health opportunities of individuals based on their social position. DESIGN: Integrative review. DATA SOURCES: (May 2020 through July 2020) Data sources included PubMed, sociological abstracts, ScienceDirect, CINAHL and Google Scholar. REVIEW METHODS: Quantitative, qualitative and theoretical articles describing the association of social determinants of health inequities and chronic kidney disease awareness were included. RESULTS: A total of 19 articles were reviewed: two qualitative, one theoretical and 16 quantitative. CONCLUSION: Findings from this review revealed that socioeconomic status, education, race and gender are consistently associated with patient chronic kidney disease awareness. These findings should serve as a basis for further research on interventions to improve chronic kidney disease awareness as well as guide nurses and health care professionals in caring for this population.


Subject(s)
Renal Insufficiency, Chronic , Social Determinants of Health , Educational Status , Health Inequities , Humans , United States
6.
J Adv Nurs ; 78(7): 1851-1869, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35362166

ABSTRACT

AIMS: The aim of this review was to evaluate the current state of scientific knowledge describing the mental health of Black men who have experienced incarceration. DESIGN: This systematic mixed studies review employed a sequential explanatory design integrating quantitative and qualitative published research. DATA SOURCES: PubMed, CINAHL, PsycINFO, Social Work and Criminal Justice databases were searched using search terms addressing core constructs of mental health, Black men, incarceration and re-entry, January 2010 through October 2021. REVIEW METHODS: Articles identified through a search protocol were screened for inclusion as: peer-reviewed original research, published in English and relevant to the mental health of formerly incarcerated Black men in the United States. RESULTS: Twenty-three articles met inclusion criteria. Quantitative findings demonstrated significant associations between incarceration history and poor mental health, including higher levels of psychological distress, increased severity of depressive and PTSD symptoms, and delayed mental health treatment. Discrimination, negative police encounters, solitary confinement and difficulty finding employment were associated with the relationship between incarceration and mental health outcomes. Four themes were identified from the qualitative synthesis: (1) Social Determinants of Mental Health (2) Pushing Through Emotional Despair (3) Challenges to Healthcare Engagement and (4) Gender, Race and Intersections between Social Identities. IMPACT: The United States has the highest rate of incarceration in the world and disproportionately incarcerates Black men. This review contextualizes the relationship between incarceration history and mental health in the lived experiences and perspectives of formerly incarcerated Black men. Findings indicate the need for interventions to support mental health needs and prevent downstream health consequences in this population. CONCLUSION: Mental health concerns are pervasive in formerly incarcerated Black men; to address key gaps in current scientific understandings future research should focus on how Black men navigate help-seeking experiences and use mental health services in the context of an incarceration history.


Subject(s)
Black or African American , Prisoners , Black or African American/psychology , Humans , Male , Mental Health , Outcome Assessment, Health Care , Qualitative Research , United States
7.
Nurs Educ Perspect ; 43(1): 19-23, 2022.
Article in English | MEDLINE | ID: mdl-34319265

ABSTRACT

BACKGROUND: The literature lacks description of the incidence of nursing students failing and repeating courses. Nursing student repeaters delay graduation and entry into the workforce; they are also at risk for attrition. AIM: The aim of the study was to describe the incidence of nursing student repeaters and progression policies in the United States. METHOD: A national survey of prelicensure nursing program deans and directors was conducted. RESULTS: Invitations were sent to 2,055 nursing programs; the response rate was 32 percent. The annual incidence of nursing student course repetition was found to be 11.5 percent. Progression policies varied widely. CONCLUSION: Nursing student repeaters are a significant population, and examination of progression policies is warranted.


Subject(s)
Education, Nursing, Baccalaureate , Students, Nursing , Humans , Policy , United States
8.
Nurs Outlook ; 70(6 Suppl 1): S32-S37, 2022.
Article in English | MEDLINE | ID: mdl-36446538

ABSTRACT

Dismantling structural racism in nursing research is key to achieving health equity for populations that experience disproportionate burden of health disparities. Several nursing organizations have advocated for the nursing profession to address structural racism in the discipline and the Future of Nursing 2020 to 2030: Charting a Path to Achieve Health Equity specifically calls for research that addresses equity and social justice. Bold calls to conduct research to address structural racism notwithstanding, what remains less clear are the strategies needed. We propose key considerations for the design of research to address structural racism and offer examples from behavioral and biobehavioral research designed to dismantle structural racism.


Subject(s)
Health Equity , Nursing Research , Humans , Systemic Racism , Social Justice
9.
J Am Psychiatr Nurses Assoc ; 28(2): 117-127, 2022 03.
Article in English | MEDLINE | ID: mdl-35176886

ABSTRACT

BACKGROUND: Long-acting injectable antipsychotics (LAIs) are unique and effective pharmacological treatment options for schizophrenia that are underutilized in clinical practice. Research surrounding prescriber barriers to the underuse of LAIs are limited to a few seminal studies which identified psychiatric prescriber barriers to the use of LAIs as knowledge deficits, uninformed attitudes, and poor prescribing practices. There is a gap in the literature regarding effective educational interventions to target the identified psychiatric prescriber barriers to the use of LAIs. AIMS: The study aimed to develop a web-based educational toolkit that would positively affect the knowledge, attitudes, and practices of psychiatric prescribers regarding LAIs. METHODS: A one-group, before and after design with a convenience, purposive sample of 17 psychiatric prescribers to assess the knowledge, attitudes, and practices (KAP) using a 20-item KAP questionnaire before and after a presentation of a web-based educational toolkit about LAIs was chosen. RESULTS: The web-based educational toolkit slightly improved the total and three subscales KAP scores of psychiatric prescribers. However, only the difference in total KAP scores was found to be statistically significant. CONCLUSIONS: The developed and evaluated web-based educational toolkit could provide a foundation for positive change to psychiatric prescribers' KAP regarding LAIs.


Subject(s)
Antipsychotic Agents , Antipsychotic Agents/therapeutic use , Educational Status , Ethnicity , Health Knowledge, Attitudes, Practice , Humans , Internet
10.
Circulation ; 141(22): e864-e878, 2020 06 02.
Article in English | MEDLINE | ID: mdl-32349542

ABSTRACT

Many individuals living with heart failure (HF) rely on unpaid support from their partners, family members, friends, or neighbors as caregivers to help manage their chronic disease. Given the advancements in treatments and devices for patients with HF, caregiving responsibilities have expanded in recent decades to include more intensive care for increasingly precarious patients with HF-tasks that would previously have been undertaken by healthcare professionals in clinical settings. The specific tasks of caregivers of patients with HF vary widely based on the patient's symptoms and comorbidities, the relationship between patient and caregiver, and the complexity of the treatment regimen. Effects of caregiving on the caregiver and patient range from physical and psychological to financial. Therefore, it is critically important to understand the needs of caregivers to support the increasingly complex medical care they provide to patients living with HF. This scientific statement synthesizes the evidence pertaining to caregiving of adult individuals with HF in order to (1) characterize the HF caregiving role and how it changes with illness trajectory; (2) describe the financial, health, and well-being implications of caregiving in HF; (3) evaluate HF caregiving interventions to support caregiver and patient outcomes; (4) summarize existing policies and resources that support HF caregivers; and (5) identify knowledge gaps and future directions for providers, investigators, health systems, and policymakers.


Subject(s)
Caregivers , Heart Failure/therapy , Home Nursing , Caregiver Burden/epidemiology , Caregiver Burden/prevention & control , Caregivers/psychology , Caregivers/statistics & numerical data , Caregivers/supply & distribution , Comorbidity , Decision Making , Health Policy , Health Services Needs and Demand , Home Nursing/economics , Home Nursing/standards , Home Nursing/statistics & numerical data , Humans , Role , Social Responsibility , Social Support , Telemedicine , Terminal Care
11.
J Infect Dis ; 222(10): 1641-1650, 2020 10 13.
Article in English | MEDLINE | ID: mdl-32692363

ABSTRACT

Novel therapies to counteract multidrug-resistant gonorrhea are urgently needed. A unique gonococcal immune evasion strategy involves capping of lipooligosaccharide (LOS) with sialic acid by gonococcal sialyltransferase (Lst), utilizing host-derived CMP-sialic acid (CMP-Neu5Ac in humans). LOS sialylation renders gonococci resistant to complement and cationic peptides, and down-regulates the inflammatory response by engaging siglecs. CMP-sialic acid analogs (CMP-nonulosonates [CMP-NulOs]) such as CMP-Leg5,7Ac2 and CMP-Kdn are also utilized by Lst. Incorporation of these NulO analogs into LOS maintains gonococci susceptible to complement. Intravaginal administration of CMP-Kdn or CMP-Leg5,7Ac2 attenuates gonococcal colonization of mouse vaginas. Here, we identify a key mechanism of action for the efficacy of CMP-NulOs. Surprisingly, CMP-NulOs remained effective in complement C1q-/- and C3-/- mice. LOS Neu5Ac, but not Leg5,7Ac2 or Kdn, conferred resistance to the cathelicidins LL-37 (human) and mouse cathelicidin-related antimicrobial peptide in vitro. CMP-NulOs were ineffective in Camp-/- mice, revealing that cathelicidins largely mediate the efficacy of therapeutic CMP-NulOs.


Subject(s)
Cathelicidins/pharmacology , Cytidine Monophosphate/analogs & derivatives , Cytidine Monophosphate/metabolism , Cytidine Monophosphate/pharmacology , Gonorrhea/drug therapy , N-Acetylneuraminic Acid/metabolism , Animals , Antimicrobial Cationic Peptides/pharmacology , Complement System Proteins , Cytidine Monophosphate/genetics , Female , Lipopolysaccharides , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Knockout , Neisseria gonorrhoeae/drug effects , Neisseria gonorrhoeae/metabolism , Neuraminic Acids , Sialic Acids , Sialyltransferases/metabolism
12.
J Immunol ; 201(9): 2700-2709, 2018 11 01.
Article in English | MEDLINE | ID: mdl-30266769

ABSTRACT

Novel therapeutics against multidrug-resistant Neisseria gonorrhoeae are urgently needed. Gonococcal lipooligosaccharide often expresses lacto-N-neotetraose (LNnT), which becomes sialylated in vivo, enhancing factor H (FH) binding and contributing to the organism's ability to resist killing by complement. We previously showed that FH domains 18-20 (with a D-to-G mutation at position 1119 in domain 19) fused to Fc (FHD1119G/Fc) displayed complement-dependent bactericidal activity in vitro and attenuated gonococcal vaginal colonization of mice. Gonococcal lipooligosaccharide phase variation can result in loss of LNnT expression. Loss of sialylated LNnT, although associated with a considerable fitness cost, could decrease efficacy of FHD1119G/Fc. Similar to N. meningitidis, gonococci also bind FH domains 6 and 7 through Neisserial surface protein A (NspA). In this study, we show that a fusion protein comprising FH domains 6 and 7 fused to human IgG1 Fc (FH6,7/Fc) bound to 15 wild-type antimicrobial resistant isolates of N. gonorrhoeae and to each of six lgtA gonococcal deletion mutants. FH6,7/Fc mediated complement-dependent killing of 8 of the 15 wild-type gonococcal isolates and effectively reduced the duration and burden of vaginal colonization of three gonococcal strains tested in wild-type mice, including two strains that resisted complement-dependent killing but on which FH6,7/Fc enhanced C3 deposition. FH/Fc lost efficacy when Fc was mutated to abrogate C1q binding and in C1q-/- mice, highlighting the requirement of the classical pathway for its activity. Targeting gonococci with FH6,7/Fc provides an additional immunotherapeutic approach against multidrug-resistant gonorrhea.


Subject(s)
Gonorrhea , Immunoglobulin Fc Fragments , Immunotherapy/methods , Recombinant Fusion Proteins/pharmacology , Animals , Complement Factor H , Humans , Immunoglobulin G , Mice , Neisseria gonorrhoeae/immunology
13.
J Infect Dis ; 219(7): 1130-1137, 2019 03 15.
Article in English | MEDLINE | ID: mdl-30346576

ABSTRACT

BACKGROUND: Meningococcal outer membrane vesicle (OMV) vaccines are prepared with detergents to remove endotoxin, which also remove desirable antigens such as factor H binding protein (FHbp). Native OMV (NOMV) vaccines with genetically attenuated endotoxin do not require detergent treatment and elicit broader serum bactericidal antibody (SBA) responses than OMV or recombinant FHbp (rFHbp) vaccines. METHODS: We measured human complement-mediated SBA responses in mice immunized with NOMV with overexpressed FHbp subfamily B (NOMV-FHbp), NOMV with FHbp genetically inactivated (NOMV-KO), and/or a control rFHbp vaccine against meningococcal and gonococcal strains. RESULTS: Despite having 36-fold less FHbp per dose, the NOMV-FHbp vaccine elicited a ≥3-fold higher serum IgG anti-FHbp geometric mean titer than control vaccines containing rFHbp (P ≤ .003). Against 2 meningococcal outbreak strains with mismatched PorA and heterologous FHbp subfamily B sequence variants, the NOMV-FHbp vaccine produced ≥30-fold higher SBA titers than control vaccines. Mice immunized with NOMV-FHbp and NOMV-KO vaccines also elicited SBA against a gonococcal strain (P < .0001 vs the adjuvant-only control group). In contrast, 2 licensed meningococcal serogroup B vaccines, including one containing detergent-extracted OMV, did not produce gonococcal SBA in humans. CONCLUSIONS: A meningococcal NOMV vaccine elicits SBA against gonococci and with overexpressed FHbp elicits SBA against meningococci.


Subject(s)
Antibodies, Bacterial/blood , Antigens, Bacterial/immunology , Bacterial Outer Membrane Proteins/immunology , Bacterial Proteins/immunology , Meningococcal Vaccines/immunology , Neisseria gonorrhoeae/immunology , Neisseria meningitidis/immunology , Animals , Antigens, Bacterial/genetics , Bacterial Proteins/genetics , Endotoxins/genetics , Female , Gene Knockout Techniques , Humans , Immunoglobulin G/blood , Mice , Vaccines, Attenuated/immunology
14.
J Christ Nurs ; 37(1): 38-45, 2020.
Article in English | MEDLINE | ID: mdl-31809379

ABSTRACT

High mortality rates continue among African Americans related to complications of uncontrolled hypertension. The purpose of this study was to determine if a faith-based self-management education program would improve self-care activities related to the management of hypertension among African American adults. Ten African American adults who reported a diagnosis of hypertension for 6 months or longer completed an 8-week education program focused on strategies for hypertension management. The education program was enhanced with the utilization of spiritual components of prayer, Scripture reading, and journaling.


Subject(s)
Black or African American/statistics & numerical data , Christianity , Hypertension/ethnology , Hypertension/therapy , Self Care/statistics & numerical data , Spirituality , Adult , Female , Humans , Life Style , Male , Middle Aged
15.
Infect Immun ; 87(2)2019 02.
Article in English | MEDLINE | ID: mdl-30510105

ABSTRACT

Neisseria gonorrhoeae, the causative agent of gonorrhea, has evolved several mechanisms to subvert complement, including binding of the complement inhibitor factor H (FH). We previously reported FH binding to N. gonorrhoeae independently of lipooligosaccharide (LOS) sialylation. Here we report that factor H-like protein 1 (FHL-1), which contains FH domains 1 through 7 and possesses complement-inhibitory activity, also binds to N. gonorrhoeae The ligand for both FH and FHL-1 was identified as neisserial surface protein A (NspA), which has previously been identified as a ligand for these molecules on Neisseria meningitidis As with N. meningitidis NspA (Nm-NspA), N. gonorrhoeae NspA (Ng-NspA) bound FH/FHL-1 through FH domains 6 and 7. Binding of FH/FHL-1 to NspA was human specific; the histidine (H) at position 337 of domain 6 contributed to human-specific FH binding to both Ng- and Nm-NspA. FH/FHL-1 bound Nm-NspA better than Ng-NspA; introducing Q at position 73 (loop 2, present in Ng-NspA) or replacing V and D at positions 112 and 113 in Nm-NspA loop 3 with A and H (Ng-NspA), respectively, reduced FH/FHL-1 binding. The converse Ng-NspA to Nm-NspA mutations increased FH/FHL-1 binding. Binding of FH/FHL-1 through domains 6 and 7 to N. gonorrhoeae increased with truncation of the heptose I (HepI) chain of LOS and decreased with LOS sialylation. Loss of NspA significantly decreased serum resistance of N. gonorrhoeae with either wild-type or truncated LOS. This report highlights the role for NspA in enabling N. gonorrhoeae to subvert complement despite LOS phase variation. Knowledge of FH-NspA interactions will inform the design of vaccines and immunotherapies against the global threat of multidrug-resistant gonorrhea.


Subject(s)
Bacterial Outer Membrane Proteins/immunology , Complement C3b Inactivator Proteins/immunology , Complement Factor H/immunology , Gonorrhea/immunology , Neisseria gonorrhoeae/immunology , Neisseria meningitidis/immunology , Bacterial Adhesion/immunology , Cells, Cultured , Humans , Neisseria gonorrhoeae/pathogenicity
16.
Nurse Res ; 26(2): 14-18, 2019 09 21.
Article in English | MEDLINE | ID: mdl-30187742

ABSTRACT

BACKGROUND: Qualitative research skills, especially those used in narrative inquiry, are challenging to develop. While the literature provides guidance on some techniques, such as collecting data, few authors share the complex process of data analysis. AIM: To offer a possible road map for novice researchers learning to analyse data generated by narrative inquiry. DISCUSSION: The author describes how a novice qualitative researcher analysed data collected using narrative inquiry with nursing students who failed and then repeated a course. This article shares a step-by-step explanation of how data were analysed, including using qualitative data analysis software to manage the data. CONCLUSION: The process of analysing qualitative data is ill-defined, with great variability among researchers and methodologies. It can be valuable for novice researchers to consider the experiences of others when planning their analysis.


Subject(s)
Narration , Qualitative Research , Learning , Research Personnel , Students, Nursing
17.
Infect Immun ; 86(8)2018 08.
Article in English | MEDLINE | ID: mdl-29844237

ABSTRACT

Sialylation of lacto-N-neotetraose (LNnT) extending from heptose I (HepI) of gonococcal lipooligosaccharide (LOS) contributes to pathogenesis. Previously, gonococcal LOS sialyltransterase (Lst) was shown to sialylate LOS in Triton X-100 extracts of strain 15253, which expresses lactose from both HepI and HepII, the minimal structure required for monoclonal antibody (MAb) 2C7 binding. Ongoing work has shown that growth of 15253 in cytidine monophospho-N-acetylneuraminic acid (CMP-Neu5Ac)-containing medium enables binding to CD33/Siglec-3, a cell surface receptor that binds sialic acid, suggesting that lactose termini on LOSs of intact gonococci can be sialylated. Neu5Ac was detected on LOSs of strains 15253 and an MS11 mutant with lactose only from HepI and HepII by mass spectrometry; deleting HepII lactose rendered Neu5Ac undetectable. Resistance of HepII lactose Neu5Ac to desialylation by α2-3-specific neuraminidase suggested an α2-6 linkage. Although not associated with increased factor H binding, HepII lactose sialylation inhibited complement C3 deposition on gonococci. Strain 15253 mutants that lacked Lst or HepII lactose were significantly attenuated in mice, confirming the importance of HepII Neu5Ac in virulence. All 75 minimally passaged clinical isolates from Nanjing, China, expressed HepII lactose, evidenced by reactivity with MAb 2C7; MAb 2C7 was bactericidal against the first 62 (of 75) isolates that had been collected sequentially and were sialylated before testing. MAb 2C7 effectively attenuated 15253 vaginal colonization in mice. In conclusion, this novel sialylation site could explain the ubiquity of gonococcal HepII lactose in vivo Our findings reinforce the candidacy of the 2C7 epitope as a vaccine antigen and MAb 2C7 as an immunotherapeutic antibody.


Subject(s)
Gonorrhea/microbiology , Heptoses/metabolism , Lactose/metabolism , Lipopolysaccharides/metabolism , N-Acetylneuraminic Acid/metabolism , Neisseria gonorrhoeae/metabolism , Neisseria gonorrhoeae/pathogenicity , Adult , Animals , Antibodies, Bacterial/immunology , Antibodies, Bacterial/metabolism , Antibodies, Monoclonal/immunology , Antibodies, Monoclonal/metabolism , China , Disease Models, Animal , Female , Healthy Volunteers , Humans , Lipopolysaccharides/chemistry , Male , Mass Spectrometry , Mice , Microbial Viability/drug effects , N-Acetylneuraminic Acid/analysis , Neisseria gonorrhoeae/chemistry , Neisseria gonorrhoeae/isolation & purification
18.
J Immunol ; 196(11): 4576-86, 2016 06 01.
Article in English | MEDLINE | ID: mdl-27183633

ABSTRACT

Neisseria gonorrhoeae, the causative agent of the sexually transmitted infection, gonorrhea, has developed resistance to most conventional antibiotics. Safe and effective vaccines against gonorrhea are needed urgently. A candidate vaccine that targets a lipooligosaccharide (LOS) epitope recognized mAb 2C7 attenuates gonococcal burden in the mouse vaginal colonization model. Glycan extensions from the LOS core heptoses (HepI and HepII) are controlled by phase-variable LOS glycosyltransferase (lgt) genes; we sought to define how HepI glycan extensions affect mAb 2C7 function. Isogenic gonococcal mutants in which the lgt required for mAb 2C7 reactivity (lgtG) was genetically locked on and the lgt loci required for HepI variation (lgtA, lgtC, and lgtD) were genetically locked on or off in different combinations were created. We observed 100% complement-dependent killing by mAb 2C7 of a mutant that expressed lactose (Gal-Glc) from HepI, whereas a mutant that expressed Gal-Gal-Glc-HepI fully resisted killing (>100% survival). Mutants that elaborated 4- (Gal-GlcNAc-Gal-Glc-HepI) and 5-glycan (GalNAc-Gal-GlcNAc-Gal-Glc-HepI) structures displayed intermediate phenotypes (<50% killing with 2 µg/ml and >95% killing with 4 µg/ml mAb 2C7). The contrasting phenotypes of the lactose-HepI and the Gal-Gal-Glc-HepI LOS structures were recapitulated with phase variants of a recently isolated clinical strain. Despite lack of killing of the Gal-Gal-Glc-HepI mutants, mAb 2C7 deposited sufficient C3 on these bacteria for opsonophagocytic killing by human neutrophils. In conclusion, mAb 2C7 showed functional activity against all gonococcal HepI LOS structures defined by various lgtA/C/D on/off combinations, thereby providing further impetus for use of the 2C7 epitope in a gonococcal vaccine.


Subject(s)
Antibodies, Viral/immunology , Heptoses/immunology , Lipopolysaccharides/immunology , Neisseria gonorrhoeae/immunology , Viral Vaccines/immunology , Humans
19.
J Immunol ; 196(4): 1732-40, 2016 Feb 15.
Article in English | MEDLINE | ID: mdl-26773149

ABSTRACT

Neisseria gonorrhoeae, the causative agent of the sexually transmitted infection gonorrhea, has developed resistance to almost every conventional antibiotic. There is an urgent need to develop novel therapies against gonorrhea. Many pathogens, including N. gonorrhoeae, bind the complement inhibitor factor H (FH) to evade complement-dependent killing. Sialylation of gonococcal lipooligosaccharide, as occurs in vivo, augments binding of human FH through its domains 18-20 (FH18-20). We explored the use of fusing FH18-20 with IgG Fc (FH18-20/Fc) to create a novel anti-infective immunotherapeutic. FH18-20 also binds to select host glycosaminoglycans to limit unwanted complement activation on host cells. To identify mutation(s) in FH18-20 that eliminated complement activation on host cells, yet maintained binding to N. gonorrhoeae, we created four mutations in domains 19 or 20 described in atypical hemolytic uremic syndrome that prevented binding of mutated fH to human erythrocytes. One of the mutant proteins (D to G at position 1119 in domain 19; FHD1119G/Fc) facilitated complement-dependent killing of gonococci similar to unmodified FH18-20/Fc but, unlike FH18-20/Fc, did not lyse human erythrocytes. FHD1119G/Fc bound to all (100%) of 15 sialylated clinical N. gonorrhoeae isolates tested (including three contemporary ceftriaxone-resistant strains), mediated complement-dependent killing of 10 of 15 (67%) strains, and enhanced C3 deposition (≥10-fold above baseline levels) on each of the five isolates not directly killed by complement. FHD1119G/Fc facilitated opsonophagocytic killing of a serum-resistant strain by human polymorphonuclear neutrophils. FHD1119G/Fc administered intravaginally significantly reduced the duration and burden of gonococcal infection in the mouse vaginal colonization model. FHD1119G/Fc represents a novel immunotherapeutic against multidrug-resistant N. gonorrhoeae.


Subject(s)
Complement Factor H/immunology , Gonorrhea/immunology , Immunoglobulin Fc Fragments/immunology , Immunotherapy/methods , Recombinant Fusion Proteins/immunology , Animals , Complement Factor H/pharmacology , Disease Models, Animal , Female , Flow Cytometry , Humans , Immunoglobulin Fc Fragments/pharmacology , Mice , Mice, Inbred BALB C , Neisseria gonorrhoeae/immunology , Recombinant Fusion Proteins/pharmacology
20.
J Trauma Nurs ; 25(6): 374-380, 2018.
Article in English | MEDLINE | ID: mdl-30395038

ABSTRACT

The importance of reflection and reflective practice is repeatedly reported in trauma literature, with the process of reflective practice being noted as invaluable for clinicians working within trauma settings. Although the literature on medical primary response trauma teams has reported clinicians' management of clinical roles and additional stressors, the practical applications and benefits of reflective practice insofar have not been identified in relation to complex trauma within multidisciplinary mental health services. This study aimed to identify the issues influencing the capacity for collaborative team reflective practice in a multidisciplinary child trauma mental health service within a UK National Health Service trust. Semistructured interviews were used to investigate the issues influencing the capacity for collaborative team reflective practice. The data were fully transcribed verbatim and analyzed using thematic analysis. The results suggest that clinicians working in a multidisciplinary child trauma service experience a positive benefit from collaborative team reflective practice, but that barriers exist, which influence the capacity to reflect. These include the management of reflective practice within the service, and department and service demands including the nature of the work/cases. Recommendations for the service and for future research are suggested to improve the capacity for collaborative team reflective practice.


Subject(s)
Interdisciplinary Communication , Patient Care Team/organization & administration , Quality Improvement , Trauma Centers/organization & administration , Wounds and Injuries/therapy , Adolescent , Child , Child, Preschool , Cooperative Behavior , Female , Humans , Injury Severity Score , Intersectoral Collaboration , Interviews as Topic , Male , Qualitative Research , United Kingdom , Wounds and Injuries/diagnosis
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