Profibrotic phenotype of conjunctival fibroblasts from mucous membrane pemphigoid

Ocular mucous membrane pemphigoid is an immunobullous disease in which excessive conjunctival fibrosis causes blindness, and the pathogenesis of scarring is incompletely understood. To establish whether profibrotic fibroblasts with an altered phenotype exist in ocular mucous membrane pemphigoid, we compared the functional characteristics of pemphigoid conjunctival fibroblasts to normal conjunctival fibroblasts with respect to cell division; migration; collagen contraction; matrix metalloproteinase, secretion of collagen and chemokines; and myofibroblast differentiation. We found that pemphigoid fibroblasts showed increased cell division (P = 0.01), increased migration in serum-free medium (72 ± 18 migrated cells versus 33 ± 11, P = 0.04), increased collagen contraction in the presence of 10 ng/ml tumor necrosis factor-α, increased collagen type I secretion (P = 0.03), increased secretion of matrix metalloproteinase-3 (P = 0.03), and increased secretion of eotaxin in response to interleukin-13 (P = 0.04). Differences between pemphigoid and normal conjunctival fibroblasts with respect to collagen contraction and MMP secretion in the presence of interleukin-13 were also observed. Together, these findings indicate that pemphigoid conjunctival fibroblasts have a profibrotic phenotype that is maintained in vitro. No differences between pemphigoid fibroblasts obtained from acutely inflamed versus clinically uninflamed conjunctiva were observed. Developing effective antifibrotic therapies will require understanding of the mechanisms that both induce and maintain the profibrotic phenotype.     

Intervention for stress management among skilled construction workers

Objective:Previous studies have demonstrated the need for a stress management intervention among construction workers. Construction workers, despite their degree of stress, are expected to contribute to the accomplishment of projects on construction sites. This study aimed to ascertain the effect of a group rational emotive behavior therapy (group REBT) on stress management among a select sample of skilled construction workers in construction industry in Nigeria.Methods:With a randomized controlled trial design, 160 skilled construction workers completed the study and responded to the perceived stress scale-14 and work-related irrational beliefs questionnaire. Participants were randomly allocated to either the intervention group (n = 80) or the control group (n = 80). The main method of data analysis used in the study was repeated measures within-between subjects analysis of variance statistic.Results:Results show that group REBT significantly improved stress and work-related irrational beliefs scores of the skilled construction workers after they were exposed to the intervention and compared with their colleagues in the control group. The significant reduction in stress and work-related irrational beliefs scores of the treatment group were also sustained at follow-up.Conclusion:Group REBT was significant in reducing stress and work-related irrational beliefs among the skilled construction workers.     

Impact of Timing of Sex Education on Teenage Pregnancy in Nigeria: Cross-sectional Survey of Secondary School Students

The objective of this study was to explore whether the time at which sex education was provided had any impact on reported cases of unintended pregnancies. A cross-sectional survey of secondary school students and their teachers was conducted using self-administered questionnaires. The participants were 1,234 students aged 14–17 years and 46 teachers in 5 secondary schools in South Eastern Nigeria. The outcome measures were reported pregnancies within the last 3 years by type of school and class level; class level at the time of receiving sex education at school; and age at the time of receiving sex education at home. In all schools, sex education was provided at all the junior and senior secondary school levels (JSS and SSS, respectively). Overall, reported cases of unintended pregnancies were highest among the junior students. In the private schools, four in ten teachers reported pregnancies among JSS 3 students. Almost four in ten teachers in public schools reported pregnancies among JSS 2 students. Of all the students, about three in ten reported pregnancies among JSS 2 and 3 students respectively. At home, sex education was provided at the mean age of 16 years (SD ±2.2). All participants cited financial need and marital promise as major predisposing factors. About four in ten students did not use contraceptives during their first sexual experience. This study highlights the need to introduce sex education much earlier, possibly before the JSS levels. At home, sex education may have greater impact if provided before the age of 14 years. Efforts should be made to address the factors predisposing to teenage pregnancy.     

Conjunctival Interleukin-13 Expression in Mucous Membrane Pemphigoid and Functional Effects of Interleukin-13 on Conjunctival Fibroblasts in Vitro

Interleukin-13 (IL-13) is the dominant effector cytokine of fibrosis in pulmonary and liver disease. Excessive conjunctival fibrosis in the immunobullous disease ocular mucous membrane pemphigoid (MMP) causes blindness; the pathogenesis of scarring in this disease is incompletely understood. To determine whether IL-13 is involved in conjunctival fibrosis in MMP, we studied the expression of IL-13 in ocular MMP patients before and after systemic immunosuppression and examined the effects of IL-13 on normal human conjunctival fibroblasts. We found high stromal cell expression of IL-13 in active ocular MMP by immunohistochemistry; 80% of these cells were CD3-positive T cells. Following immunosuppression, in clinically uninflamed, treated, ocular MMP patients, the number of IL-13 positive cells was significantly reduced, but this was still fourfold greater than in normal conjunctiva. IL-13 stimulated collagen lattice contraction and migration, and decreased production of mmp-3 and mmp-10 by human conjunctival fibroblasts. The addition of T cell culture supernatant to IL-13 synergistically augmented fibroblast migration. IL-13 also up-regulated surface expression of HLA-DR, CD80, CD40, and CD154 by conjunctival fibroblasts, suggesting a potential mechanism for fibroblast-T cell cross talk, via which fibroblasts may actively engage in perpetuating chronic inflammation and continued fibrosis. Together, these findings suggest that IL-13 is involved in conjunctival fibrosis in MMP, and that IL-13 has both profibrotic and pro-inflammatory effects on human conjunctival fibroblasts.Autoimmune conjunctivitis caused by ocular mucous membrane pemphigoid (MMP), also known as ocular cicatricial pemphigoid, is a blinding disease characterized by recurrent episodes of inflammation and aggressive conjunctival fibrosis. It is part of a spectrum of immunobullous disease associated with linear deposition of IgG and IgA autoantibodies directed against epithelial basement membrane zone proteins, which most commonly involves oral and ocular mucosa. In ocular mucosa, unlike oral mucosa, scarring is a clinical hallmark of the disease.¹ Although the mechanisms have not been clearly demonstrated, autoantibodies are thought to cause blistering by disrupting basement membrane adherence via activation of complement, neutrophils and pro-inflammatory cytokines.² In the eye, blisters are infrequently seen, and the disease manifests as chronic recurrent cicatricial conjunctivitis.The functional consequences of the inflammatory lesions that heal with scarring are most evident in the eye, where patients with severe conjunctival fibrosis become blind in 30% of cases.³ Developing effective anti-fibrotic agents would therefore have therapeutic potential, but is challenging because the cellular and molecular mechanisms of conjunctival scarring in MMP are incompletely understood. Given that conjunctival fibrosis can still progress, despite apparent clinical control of inflammation by conventional immunosuppressive therapy,^4,5 better understanding of the changes in treated tissue compared with actively inflamed tissue might assist and guide in the development of adjunctive local therapies to target conjunctival fibrosis.Interleukin-13 is a key profibrotic mediator that has been identified as the dominant effector cytokine of fibrosis in experimental models of skin, hepatic, and pulmonary fibrosis and airway remodeling in asthma.^6,7,8,9 It is produced by type 2 helper T cell (Th2) cells, mast cells, and basophils, and is a potent stimulator of eosinophil-, lymphocyte- and macrophage-rich inflammation, mucosal metaplasia, tissue fibrosis, and parenchymal remodeling.^10,11 Fibrosis associated with repetitive injury in chronic inflammatory disease is strongly linked with CD4⁺ Th2 responses involving interleukin (IL)-4, IL-5, IL-13, and IL-21.¹² As CD4⁺ and CD8⁺ T cells are the predominant cells in the conjunctival subepithelial infiltrate in ocular MMP,^13,14,15 it has been hypothesized that T cells play an important role in the pathogenesis of conjunctival fibrosis in MMP. As in most chronic immune-mediated fibroproliferative disorders,¹⁶ both Th1 (interferon [IFN]γ) and Th2 cytokines (IL-4, IL-5) are present in MMP lesions,^17,18,19,20 but it is not known whether the Th2 cytokine IL-13 plays a role in the autoimmune conjunctivitis and fibrosis observed in ocular MMP.IL-13 is unique in that it is not thought to exert any control over T cell function,¹⁰ so unlike IL-4, it does not appear to be important in the initial differentiation of CD4⁺T cells into Th2-type cells, but rather appears to be important in the effector phase of inflammation and repair, via its effects on monocytes/macrophages, dendritic cells, fibroblasts, and other inflammatory and stromal cells. IL-13 has been shown to exert direct pro-fibrotic effects on fibroblasts isolated from human lung and skin.^21,22,23,24 Fibroblasts isolated from different bodily sites exhibit different functional properties and site-specific gene expression,²⁵ so these effects cannot necessarily be extrapolated to fibroblasts from other tissues such as the conjunctiva. Although the effects of IL-13 on normal human conjunctival fibroblast proliferation, apoptosis, and matrix metalloproteinase expression have been reported,^26,27 its effects on other functional activities carried out by normal conjunctival fibroblasts have not been fully investigated.Fibrosis is an excessive repair response, where the replacement of normal parenchymal tissue by connective tissues is uncontrolled, and there is an imbalance between accumulation of extracellular matrix, and remodeling and collagen turnover. Fibrosis typically results from chronic inflammation due to a persistent irritant that damages tissues.^12,28 Inflammatory cells, including macrophages and Th2 lymphocytes, play important roles in the chronic inflammation resulting in fibrosis, by releasing cytokines, chemokines, and growth factors, and also through direct interaction with fibroblasts.^12,16,28 Rather than simply being structural cells, it is also recognized that fibroblasts play an active role in the persistence of inflammation by secreting cytokines and chemokines, recruiting and maintaining the survival of T cells and other inflammatory cells via both soluble factors, and by direct cross talk with lymphocytes via the CD40/CD154 pathway.^25,29 It has previously been shown that IFNγ up-regulates CD40 expression on human lung fibroblasts, and that IL-13 increases CD154 levels in human lung fibroblasts, but the effects of IL-13 on co-stimulatory molecule expression by human conjunctival fibroblasts has yet to be elucidated.In the present study, we sought to explore the potential role of IL-13 in ocular MMP, and its effects on conjunctival fibroblast-related profibrotic and pro-inflammatory activity.     

Repeated inoculation of killed Leishmania major induces durable immune response that protects mice against virulent challenge

It is widely believed that persistence of live parasites at the primary site of infection is important for maintenance of anti-Leishmania immunity. However, whether this immunity requires only the presence of antigen and not necessarily live replicating parasites has not been investigated. To determine whether non-replicating antigens could induce and maintain anti-Leishmania immunity, we inoculated naïve mice with killed parasites (once or 5 times weekly) either alone or in combination with rIL-12 and challenged them with virulent Leishmania major parasites at different times after inoculation. We found that similar to mice that recovered from virulent live L. major infection, mice inoculated repeatedly with killed parasites were protected against virulent L. major challenge. The protection obtained following 5 weekly inoculations of killed parasites was associated with strong antigen-specific IFN-γ production by cells from the lymph nodes draining the inoculation site. In contrast, mice that received a single or double inoculation of killed parasites either alone or followed with repeated rIL-12 injection were not protected. Repeated antigen inoculation resulted in increased numbers of the IFN-γ-secreting CD44⁺CD62L⁻ T cells that were comparable in magnitude to that seen in mice with persistent infections. Overall, these results suggest that it is possible to generate and maintain anti-Leishmania immunity for a relatively long period of time in the absence of live replicating parasites. However, a certain threshold of effector cells has to be generated in order to achieve this protection.     

Spontaneous enterocutaneous fistula--A rare presentation of enteric fever

BACKGROUND: Enterocutaneous fistulae (ECFs) after typhoid perforation have been previously recorded postoperatively due to repair leak or new perforation. Spontaneous ECF formation due to primary intra-abdominal pathologic processes has been attributed to infectious diseases such as tuberculosis and Crohn's disease. A review of the literature has shown no previous report of spontaneous ECF caused primarily by salmonella typhi infection. OBJECTIVE: To report a case of spontaneous ECF due to salmonella typhi infection. CASE REPORT: An eight-year-old female presented with high fever and weight loss of two weeks' duration and a one-week history of a foul-smelling umbilical discharge. She was ill looking, wasted, with evidence of peritonitis. An emergency exploratory laparotomy revealed multiple perforations at the antimesenteric border of the ileocecal valve. With intestinal resection and anastomosis and the use of broad spectrum antibiotics, her clinical state improved. Tissue biopsy showed hemorrhagic necrosis with infiltration by mononuclear inflammatory cells. CONCLUSION: ECF is a rare complication of enteric fever, Enteric fever should therefore be considered in ill children presenting with ECF in the absence of a history of previous surgery, or blunt or penetrating trauma.     

Persistent parasites and immunologic memory in cutaneous leishmaniasis: implications for vaccine designs and vaccination strategies

Despite a plethora of publications on the murine model of cutaneous leishmaniasis and their contribution to our understanding of the factors that regulate the development of CD4+ T cell immunity in vivo, there is still no effective vaccine against the human disease. While recovery from natural or experimental infection with Leishmania major, the causative agent of human cutaneous leishmaniasis, results in persistence of parasites at the primary infection site and the development of long-lasting immunity to reinfection, vaccination with killed parasites or recombinant proteins induces only short-term protection. The reasons for the difference in protective immunity following recovery from live infection and vaccination with heat-killed parasites are not known. This may in part be related to persistence of live parasites following healing of primary cutaneous lesions, because complete clearance of parasites leads to rapid loss of infection-induced immunity. Recent reports indicate that in addition to persistent parasites, IL-10-producing natural regulatory T cells may also play critical roles in the maintenance and loss of infection-induced immunity. This review focuses on current understanding of the factors that regulate the development, maintenance and loss of anti-Leishmania memory responses and highlights the role of persistent parasites and regulatory T cells in this process. Understanding these factors is crucial for designing effective vaccines and vaccination strategies against cutaneous leishmaniasis.     

All-epiphyseal versus trans-epiphyseal screw fixation for tillaux fractures: Does it matter?

BACKGROUNDTillaux fractures occur primarily in adolescents due to the pattern of physeal closure and are classified as Salter-Harris type III physeal fractures. Operative management with screw fixation is recommended for more than 2 mm of displacement or more than 1 mm of translation. However, the efficacy and complications of trans-physeal vs all-physeal screw fixation have not been investigated extensively.AIMTo compare the clinical and functional outcomes of trans-physeal (oblique) and all-epiphyseal (parallel) screw fixation in management of Tillaux fractures among pediatric patients. METHODSThis was an ethics board approved retrospective review of pediatric patients who presented to our tertiary children’s care facility with Tillaux fractures. We included patients who had surgical fixation of a Tillaux fracture over a 10 year period. Data analysis included demographics, mode of injury, management protocols, and functional outcomes. The patients were divided into group 1 (oblique fixation) and group 2 (parallel fixation). Baseline patient characteristics and functional outcomes were compared between groups. Statistical tests to evaluate differences included Fisher’s Exact or Chi-squared and independent samples t or Mann Whitney tests for categorical and continuous variables, respectively.RESULTSA total of 42 patients (28 females and 14 males) were included. There were no significant differences in body mass index, sex, age, or time to surgery between the groups [IK2]. Sports injuries accounted for 61.9% of the cases, particularly non-contact (57.1%) and skating (28.6%) injuries. Computed Tomography (CT) scan was ordered for 28 patients (66.7%), leading to diagnosis confirmation in 17 patients and change in management plan in 11 patients. [GRC3] Groups 1 and 2 consisted of 17 and 25 patients, respectively. For mid to long-term functional outcomes, there were 14 and 10 patients in groups 1 and 2, respectively. Statistical analysis revealed no significant differences in the functional outcomes, pain scores, or satisfaction between groups. No infections, non-unions, physeal arrest, or post-operative ankle deformities were reported. Two (4.8%) patients had difficulty returning to sports post-surgery due to pain. One was a dancer, and the other patient had pain while running, which led to hardware removal. Both patients had parallel fixation. Hardware removal for groups 1 and 2 were 4 (23.5%) and 5 (20.0%) patients, respectively. The reasons for removal was pain in 2 patients, and parental preference in the remaining. CONCLUSIONThis is the largest reported series of pediatric patients with Tillaux fractures comparing functional outcomes of different methods of screw fixation orientation to the physis, which showed no difference regarding functional outcomes.     

Folate levels in children with sickle cell anaemia on folic acid supplementation in steady state and crises at a tertiary hospital in Enugu,Nigeria: a prospective,comparative study

IntroductionFolic acid supplementation is an integral aspect of the management of children with sickle cell anaemia (SCA) especially in Africa. In spite of this, there have been concerns about lower folate levels, especially during crisis.AimTo determine red cell folate levels of children with sickle cell anaemia in steady state and during crisis and compare with those with haemoglobin AA genotype.MethodThis study was prospective, hospital based, and comparative. Fifty children with sickle cell anaemia were recruited during crises and followed up until they met the criteria for attaining steady state. The controls were fifty children matched with those with SCA for age and gender and had haemoglobin AA genotype. Red cell folate estimation was done with the Electrochemiluminescence Immunoassay (ECLIA) method using the automated Roche Cobas e411 equipment.ResultsThe median (IQR) red cell folate level in children during sickle cell crisis was 265.95 (134.50) ng/ml, which was significantly lower than the median (IQR) of 376.30 (206.85) ng/ml obtained during steady state. Most children with SCA (41 out of 50) had significantly higher folate levels during steady state (T=1081, Z-score= -4.660, p < 0.001). Median level of red cell folate was lower during anaemic crisis compared to vaso-occlusive crisis, though not significantly so (N(50), U = 214.00, Z-score= -1.077, p = 0.305). The median red cell folate level of normal controls was 343.55 (92.90) ng/ml, which was significantly lower than the 376.30 (206.85) ng/ml obtained during steady state (N(50), U= 209.00, Z-score= -7.177, p <0.001).ConclusionMedian red cell folate levels of the study participants were within normal limits, though most children with SCA had significantly higher levels during steady state compared to crisis. Normal controls had significantly lower red cell folate levels than the children with SCA during steady state.