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1.
Environ Monit Assess ; 189(6): 303, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28567597

ABSTRACT

Agricultural pesticides are widely used in Suriname, an upper middle-income Caribbean country located in South America. Suriname imported 1.8 million kg of agricultural pesticides in 2015. So far, however, national monitoring of pesticides in crops is absent. Reports from the Netherlands on imported Surinamese produce from 2010 to 2015 consistently showed that samples exceeded plant-specific pesticide maximum residue limits (MRLs) of the European Union (EU). Consumption of produce containing unsafe levels of pesticide residues can cause neurological disorders, and particularly, pregnant women and children may be vulnerable. This pilot study assessed the presence of pesticide residues in commonly consumed produce items cultivated in Suriname. Thirty-two insecticides (organophosphates, organochlorines, carbamates, and pyrethroids) and 12 fungicides were evaluated for their levels in nine types of produce. Pesticide residue levels exceeding MRLs in this study regarded cypermethrin (0.32 µg/g) in tomatoes (USA MRL 0.20 µg/g), lambda-cyhalothrin (1.08 µg/g) in Chinese cabbage (USA MRL 0.40 µg/g), endosulfan (0.07 µg/g) in tannia (EU MRL 0.05 µg/g), and lindane (0.02 and 0.03 µg/g, respectively) in tannia (EU MRL 0.01 µg/g). While only a few pesticide residues were detected in this small pilot study, these residues included two widely banned pesticides (endosulfan and lindane). There is a need to address environmental policy gaps. A more comprehensive sampling and analysis of produce from Suriname is warranted to better understand the scope of the problem. Preliminary assessments, using intake rate, hazard quotient, and level of concern showed that it is unlikely that daily consumption of tannia leads to adverse health effects.


Subject(s)
Environmental Monitoring , Pesticide Residues/analysis , Vegetables/chemistry , Agriculture , Carbamates/analysis , Crops, Agricultural/chemistry , Endosulfan/analysis , Food Contamination/analysis , Food Contamination/statistics & numerical data , Fungicides, Industrial/analysis , Hexachlorocyclohexane/analysis , Humans , Hydrocarbons, Chlorinated/analysis , Insecticides/analysis , Nitriles/analysis , Pesticides/analysis , Pilot Projects , Pyrethrins/analysis , Suriname
2.
Clin Transl Oncol ; 17(3): 197-200, 2015 Mar.
Article in English | MEDLINE | ID: mdl-24965691

ABSTRACT

The discovery of an appendiceal carcinoid tumor found incidentally or during the course of diagnostic or therapeutic procedures is a burden to both the patient and clinician. The role of the correct surgical operation is paramount for lesions suspected to be malignant. In the pediatric population, appendiceal carcinoids continue to challenge the clinician in choosing the optimal treatment when lesions are larger than 2 cm or involve the appendical base. While the criteria used to define these distinct lesions are available in most cases, the management and treatment are still debated and controversial when considering more radical surgical intervention. The purpose of this article is to give an overview regarding the history, diagnosis, histopathology, management, and controversies associated with appendiceal carcinoid in the pediatric population.


Subject(s)
Appendiceal Neoplasms/surgery , Carcinoid Tumor/surgery , Appendectomy , Appendiceal Neoplasms/history , Appendiceal Neoplasms/pathology , Carcinoid Tumor/history , Carcinoid Tumor/pathology , Child , Colectomy , History, 19th Century , Humans
3.
In. Caribbean Public Health Agency. Caribbean Public Health Agency: 60th Annual Scientific Meeting. Kingston, The University of the West Indies. Faculty of Medical Sciences, 2015. p.[1-75]. (West Indian Medical Journal Supplement).
Monography in English | MedCarib | ID: med-18075

ABSTRACT

OBJECTIVE: This specific study objective was to characterize pesticide contamination in produce and medicinal plants in Suriname. DESIGN AND METHODS: Samples were collected during different seasons from several markets in Suriname. The preliminary assessment collected 8 products from the largest market in Paramaribo during the rainy season. Results from the preliminary assessment informed the selection of products for the expanded assessment, which was focused on 7 products sampled from the same market, as well as the largest market in district Wanica during the dry season. Additionally, the vegetable Tannia was sampled at 3 other markets within Paramaribo. All samples were analyzed for pesticide residue with Gas Chromatography Electron Capture Detector. RESULTS: The preliminary assessment conveyed that 12.5% of the samples tested had pesticide residues. The expanded characterization showed that 35.3% of the samples tested positive for pesticide residues. Half of all the samples with pesticide residues exceeded either 1 or more Maximum Residual Levels (MRL) in the expanded assessment. Among the identified residues were Endosulfan and Lindane, which are banned for use in Suriname and are globally being phased out under the Stockholm Convention. CONCLUSIONS: A percentage of selected produce items cultivated in Suriname were contaminated with pesticides. To ascertain the association with adverse health effects, this research will be followed up by a human health assessment that includes a dietary assessment and biomarker testing.


Subject(s)
Pesticide Residues , Chemical Contamination , Vegetables , Plants, Medicinal , Suriname
4.
Malays J Pathol ; 36(3): 201-5, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25500520

ABSTRACT

NK/T cell lymphoma, nasal type is an aggressive and uncommon malignancy. Disease that occurs outside of the aerodigestive tract exhibits an even more aggressive clinical behaviour and does not respond as well to conventional therapy compared to its nasal counterpart. We report such a case of NK/T cell lymphoma, nasal type, that presented as an anterior chest wall mass, arising from the left pectoralis muscle. An interesting feature we wish to highlight is the associated eosinophilia that corresponded to disease activity, exhibiting fluctuations with surgical resection and chemotherapy. To the best of our knowledge this is the third reported case of NK/T cell lymphoma that is associated with peripheral eosinophilia. Our case highlights the role of certain NK cell subsets that play a major role in eosinophilic activation in NK/T lymphomas and calls for more research into further classification of this disease by virtue of its NK cell subsets.


Subject(s)
Eosinophilia/pathology , Killer Cells, Natural/pathology , Lymphoma, T-Cell/pathology , T-Lymphocytes/pathology , Thoracic Wall/pathology , Aged , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Cyclophosphamide/therapeutic use , Doxorubicin/therapeutic use , Etoposide/therapeutic use , Humans , Lymphoma, T-Cell/diagnostic imaging , Lymphoma, T-Cell/drug therapy , Male , Prednisone/therapeutic use , Radiography , Thoracic Wall/diagnostic imaging
5.
Arch Pediatr ; 21(7): 750-3, 2014 Jul.
Article in French | MEDLINE | ID: mdl-24947109

ABSTRACT

Infective endocarditis (IE) is a rare, polymorphic disease in children. Mycotic aneurysm is a rare condition that complicates about 2.5 to 10% of cases of endocarditis. It is responsible for significant morbidity and mortality [1,2]. Mycotic aneurysms are often asymptomatic, physical examination is poor, but the diagnosis should be considered with the triad including fever, abdominal pain, and abdominal mass beating. Abdominal ultrasound and computed tomography are the most useful for the identification of the aneurysmal mass. However, angiography is an interesting addition to confirm the diagnosis and implement a treatment procedure [3]. The treatment of SMA aneurysms is largely surgical. IE treatment is based on antibiotic therapy combined with surgical repair. We report the case of a 15-year-old patient, first operated for an SMA aneurysm complicating the course of IE, who secondarily underwent mitral valve repair. We review the epidemiology, diagnosis, and care principles of mycotic aneurysms of the SMA.


Subject(s)
Aneurysm, Infected/complications , Endocarditis, Bacterial/complications , Mesenteric Artery, Superior , Adolescent , Aneurysm, Infected/diagnosis , Aneurysm, Infected/microbiology , Aneurysm, Infected/therapy , Echocardiography , Endocarditis, Bacterial/therapy , Female , Humans , Magnetic Resonance Angiography , Mesenteric Artery, Superior/surgery , Viridans Streptococci/isolation & purification
6.
J Nanosci Nanotechnol ; 14(1): 744-54, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24730294

ABSTRACT

Many studies have been conducted on the development of nanomaterials for medical applications. The interaction of nanomaterials with human cells is the most important criterion for biomedical application and has been studied in detail. Three common approaches have been suggested for nanomaterial mechanisms for cellular interaction and internalization: direct diffusion or disruption to the plasma membrane, endocytosis, and entry through ion channels and transporter proteins. Several important factors affect the interaction and cellular uptake of nanomaterials: size, shape, rigidity, surface properties, cell type, and endocytotic pathways. In this review, we summarize the mechanisms of cell-nanomaterial interactions, and the various factors that influence these interactions. The importance of proper cell-nanomaterial interaction for medical research applications is also highlighted. The results summarized in this review may add new dimensions to our understanding of cell-nanomaterial interactions and their applications in therapeutic and diagnostic techniques for biomedical, academic, and industrial research.


Subject(s)
Cell Membrane Permeability/physiology , Cell Membrane/chemistry , Cell Membrane/physiology , Endocytosis/physiology , Ion Channel Gating/physiology , Nanostructures/chemistry , Nanostructures/ultrastructure , Animals , Diffusion , Humans
7.
Ann Cardiol Angeiol (Paris) ; 62(2): 101-7, 2013 Apr.
Article in French | MEDLINE | ID: mdl-23312336

ABSTRACT

BACKGROUND: Aortic valve replacement improves clinical symptoms and left ventricular systolic function in patients with chronic aortic regurgitation despite a higher surgical risk. The objective of this study is to determine if left ventricular function will be normalized after surgery. PATIENTS AND METHOD: This retrospective study included 40 patients (nine females and 31 males) with chronic aortic regurgitation and left ventricular systolic dysfunction who were evaluated by echocardiography Doppler. Were included patients with left ventricular ejection fraction less or equal to 45%. Ages ranged from 18 to 77 years (mean = 46.4 ± 12.6 years). Preoperatively, six patients (15%) were asymptomatic, ten (25%) were in NYHA II, half (50%) in NYHA III and four (10%) in NYHA IV. The mean preoperative ejection fraction (EF) was 36.2 ± 2%. The mean end systolic and diastolic dimensions were 61.7 ± 8.5 mm and 78.9 ± 9.7 mm respectively. Aortic regurgitation was quantified grade III in sixteen patients (40%) and grade IV in twenty-four (60%). RESULTS: Thirty-seven patients underwent aortic valve replacement and three Bentall operations. Hospital mortality was 7.5% (3/40). The mean follow-up period was 69.7 months. All survivor patients were investigated. Out of these, five were lost and 32 were controlled. Symptomatic improvement was noted in most of the survivors. Sixty percent (24/40) were severely symptomatic before and only 6.25% (2/32) during follow-up. The ejection fraction increased significantly after surgery (36.2 ± 2% in preoperative period vs. 55.2 ± 10% in postoperative period, P < 0.02). Left ventricular diameters decreased significantly also. Survival rates were 3-year 94%, 5-year 91% and 7-year 89%. CONCLUSION: Despite reduced left ventricular systolic function, aortic valve replacement in chronic aortic regurgitation was associated with acceptable operative risk. Surgery improves functional status, symptoms and ejection fraction in most patients.


Subject(s)
Aortic Valve Insufficiency/physiopathology , Aortic Valve Insufficiency/surgery , Aortic Valve/surgery , Heart Valve Prosthesis Implantation , Ventricular Dysfunction, Left/surgery , Adolescent , Adult , Aged , Aortic Valve Insufficiency/complications , Aortic Valve Insufficiency/diagnosis , Aortic Valve Insufficiency/mortality , Female , Follow-Up Studies , Hospital Mortality , Humans , Male , Middle Aged , Postoperative Period , Preoperative Period , Retrospective Studies , Risk Assessment , Risk Factors , Severity of Illness Index , Ventricular Dysfunction, Left/complications , Ventricular Dysfunction, Left/diagnosis , Ventricular Dysfunction, Left/mortality , Ventricular Dysfunction, Left/physiopathology
8.
Microbiol Res ; 163(4): 441-4, 2008.
Article in English | MEDLINE | ID: mdl-16959478

ABSTRACT

Thielavia gigaspora sp. nov. from herbivore dung is described and illustrated. The new taxon by comparison with previously known species is distinguished by relatively large ascospores (25-38 x 15-21 microm), each showing an apical, protuberant germ pore and a longitudinal dark band. A brief comparison with morphologically related species is given.


Subject(s)
Sordariales/classification , Sordariales/isolation & purification , Animals , Camelus , Egypt , Feces/microbiology , Sordariales/cytology , Spores, Fungal/cytology
9.
Ann Cardiol Angeiol (Paris) ; 56(6): 308-12, 2007 Dec.
Article in French | MEDLINE | ID: mdl-17976511

ABSTRACT

PURPOSE: This retrospective study has for objective to compare the effect of tranexamic acid with low-dose of aprotinin therapy on blood loss in reoperative cardiac surgery. METHODS: Ninety-one adult patients underwent repeated open-heart surgery. Two groups of patients were collected. The aprotinin group AP (N=60) has received an intravenous full low dose of 500000 UIK of aprotinin. The tranexamic group TA (N=31) has received 30 mg/kg of tranexamic acid. Criteria for assessment included: cumulative blood loss at 4 hours and 20 hours after operation, need for transfusion and parameters of coagulation (platelet, fibrinogen count). RESULTS: Demographics characteristics and echocardiographic data were similar between the tow groups. Postoperative blood loss at 4th hour and at 20th hour were reduced in tranexamic group compared with aprotinin group (P=0,009, P=0,001). The transfusion requirement was frequent in the AP group 39% vs 19.4% in TA group. The TA group received fewer total unit of red blood (0.38 unit RBC/patient vs 1.06 in AP group) [RBC=red blood cells]. There was no statistically significant difference in platelet and fibrinogen profiles. CONCLUSION: This study concludes that tranexamic acid and low dose aprotinin effectively reduces postoperative bleeding in repeat open-heart surgery. However, the marked difference in superiority between these tow drug therapies needs the randomized and controlled study.


Subject(s)
Antifibrinolytic Agents/therapeutic use , Aprotinin/administration & dosage , Cardiac Surgical Procedures/methods , Hemostatics/administration & dosage , Tranexamic Acid/therapeutic use , Adult , Blood Loss, Surgical/prevention & control , Blood Transfusion , Extracorporeal Circulation/methods , Female , Fibrinogen/analysis , Humans , Injections, Intravenous , Male , Platelet Count , Postoperative Hemorrhage/prevention & control , Reoperation , Retrospective Studies , Time Factors
10.
Ann Cardiol Angeiol (Paris) ; 56(3): 111-6, 2007 Jun.
Article in French | MEDLINE | ID: mdl-17572170

ABSTRACT

AIM: The aim of this study is to stress the interest of the early surgery in infective endocarditis (IE), its indications and prognostic implications. METHODS: It is a retrospective descriptive study of 30 cases (29 men and 1 woman with an average age of 35+/-12 years) with IE underwent surgery management in the acute phase between September 1993 and June 2005. RESULTS: They were 25 rheumatic lesions, 2 aortic bicuspids and 3 mechanical valves prosthesis. Four twenty-six percent of the patients were operated for hemodynamic deterioration and 10% for embolic complication. We report 3 cases (that is to say 10%) of IE late form on prosthesis. Three patients died in the first post operative month by respectively total desinsertion of mitral prosthesis on peroperative, 1 septic shock at the 13th post operative day and 1 tamponade at the 14th postoperative day. On 72 months an average follow-up, 26 were controlled regularly: 25 evolved favourably and 1 died in third postoperative year (severe heart failure). CONCLUSION: A high early surgery rate is related to good long term results and does not increase in hospital mortality. The reduced mortality was particularly evident among patients with moderate to severe congestive heart failure.


Subject(s)
Endocarditis, Bacterial/surgery , Adult , Aged , Female , Humans , Male , Middle Aged , Retrospective Studies , Time Factors , Young Adult
11.
Ann Cardiol Angeiol (Paris) ; 56(3): 126-9, 2007 Jun.
Article in French | MEDLINE | ID: mdl-17572172

ABSTRACT

INTRODUCTION: Upper gastrointestinal haemorrhage (UGH) following cardiac surgery is infrequent with high mortality. The aim of this study is to compare the frequency and outcome of UGH in patients who had undergone open heart surgery at our institution. PATIENTS AND METHODS: From January 1994 to December 2005, 1278 cardiac operations were performed. A systematic prophylaxis antiacid was used by antagonists of histaminic receptor (anti-H2, ranitidine 150 mg/12 h) in all patients. The diagnosis was based on clinical symptoms (haematemesis and/or melaena) in the postoperative period and confirmed by fibroscopy. We conducted a retrospective study of these patients. RESULTS: Only 8 of the 1278 (0,6%) cardiac operations were complicated by UGH. Demographic data were reported in Table 1. The mean interval between surgery and UGH was 10+/-3,7 days (range 5,15 days). Gastro-duodenal ulcer was the most common cause of UGH in 5 patients (62%), ulcero-hemorrhagic eosophagitis was developed in one patient (12,5%), candidosic eosophagitis in one and multiple gastric ulcer in one patient (12,5%). Medical treatment was applied in 6 patients (72%) with successful result. Surgical intervention was necessary in 2 patients (25%). 2 patients had repeat gastrointestinal bleeding. One patient was died; he was recorded as having severe sepsis and multiple organ failure in addition to UGH. CONCLUSION: UGH in patients undergoing heart operation is rare but associated with poor prognosis despite antiacid prophylaxis. These complications occurred in patients who had in postoperative bad hemodynamic conditions.


Subject(s)
Cardiac Surgical Procedures , Gastrointestinal Hemorrhage/epidemiology , Postoperative Complications/epidemiology , Adult , Aged , Aged, 80 and over , Female , Gastrointestinal Hemorrhage/etiology , Humans , Incidence , Male , Middle Aged , Postoperative Complications/etiology , Retrospective Studies
12.
Tissue Antigens ; 68(4): 325-30, 2006 Oct.
Article in English | MEDLINE | ID: mdl-17026468

ABSTRACT

Idiopathic bronchiectasis is a disease of chronic, bacterial lung infection, unresolving inflammation and progressive lung damage. Bronchiectasis can be associated with autoimmune diseases including ulcerative colitis. Defects of both innate and adaptive immunity have been proposed. The airway inflammation is characterized by interleukin-8 (IL-8) expression and infiltration by neutrophils and T cells. Here we investigated two candidate gene polymorphisms that may contribute to disease susceptibility: a CXCR-1 (+2607 G/C) gene polymorphism that is implicated in IL-8 binding and neutrophil trafficking as well as the interferon-gamma (IFNgamma) (+874 T/A) polymorphism which is linked to levels of IFNgamma production. These polymorphisms were distributed similarly in the idiopathic bronchiectasis group and controls, suggesting that these two candidate gene polymorphisms are not associated with disease susceptibility.


Subject(s)
Bronchiectasis/genetics , Bronchiectasis/immunology , Interferon-gamma/genetics , Polymorphism, Single Nucleotide , Receptors, Interleukin-8A/genetics , Alleles , Colitis, Ulcerative/genetics , Colitis, Ulcerative/immunology , Female , Genetic Predisposition to Disease , Genotype , Humans , Male , Middle Aged
13.
Ann Cardiol Angeiol (Paris) ; 52(2): 125-8, 2003 Apr.
Article in French | MEDLINE | ID: mdl-12754971

ABSTRACT

PURPOSE: This retrospective stady has for objective to compare the effect of Tranexamic Acid (TA) to the low dose of aprotinin (AP) in primary mitral valve surgery in terms of blood loss and transfusion requirements. METHODS: Are included in the study operated patients of a valvulopathy mitral isolated. Two groups of 50 patients are collected. The tranexamic acid group has received 30 mg kg-1 the acid tranexamic and the aprotinin group has received a low regimen as 500,000 UIK of aprotinin. Blood loss by the chest drains are assessed to different times during first 24 hours post cardiopulmonary bypass. In the same way, we have measured the platelet and fibrinogen count. Blood products were administered according to a classic protocol. RESULTS: The two groups are comparable clinic and echocardiographic parameters what authorizes us an appariement acceptable. Various cardiopulmonary bypass times are almost similar. We noticed a tendency to excessive blood loss processed by low regimen aprotinin and a significant rate difference of platelet and the fibrinogen level. But no complication has been recorded in the two groups. CONCLUSIONS: This study demonstrates relatively different effect of the two fibrinolytics inhibitors in primary mitral valve surgery. As for the superiority of one of the two produces, it needs a confirmation by a randomised and controlled clinical trial.


Subject(s)
Antifibrinolytic Agents/administration & dosage , Aprotinin/administration & dosage , Blood Loss, Surgical/prevention & control , Hemostatics/administration & dosage , Mitral Valve/surgery , Tranexamic Acid/administration & dosage , Adult , Cardiopulmonary Bypass , Dose-Response Relationship, Drug , Female , Fibrinogen/analysis , Heart Valve Diseases/surgery , Humans , Male , Platelet Count , Retrospective Studies , Treatment Outcome
14.
Ann Cardiol Angeiol (Paris) ; 52(2): 129-31, 2003 Apr.
Article in French | MEDLINE | ID: mdl-12754972

ABSTRACT

We report a case of 34 years old female with a diagnosis of a big right Atrial myxoma revealed by echocardiography. The treatment consisted on a surgical excision of the tumour under extra corporal circulation. The patient made a good post-operative recovery. Authors showed the clinical signs of these tumours to be various, and echocardiography to be the definitive diagnosis procedure.


Subject(s)
Heart Failure/diagnostic imaging , Heart Neoplasms/diagnosis , Myxoma/diagnosis , Adult , Echocardiography , Female , Heart Atria/surgery , Heart Neoplasms/surgery , Humans , Myxoma/surgery
15.
Surg Endosc ; 15(7): 755-6, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11591984

ABSTRACT

BACKGROUND: Following upon the recent development of minimally invasive coronary robotic surgery, we set out to evaluate the feasibility of bilateral internal mammary artery (IMA) harvesting using the voice-controlled AESOP 2000 video assisted robot. METHODS: The robot is placed on the right side of the patient. The left IMA is first totally video-harvested, with the arm of the robot crossing over the patient to reach the left chest. The voice-controlled movement of the arm allows the surgeon to obtain the best video image of the artery. After completion of the dissection, the arm is positioned on the right part of the chest. The right IMA is then harvested using the same technique. RESULTS: Two patients underwent harvest of a bilateral IMA using this technique. The time of dissection was 52 min and 86 min, respectively. CONCLUSION: This technique allows a more precise, faster, tremor-free dissection, as compared to a conventional thoracoscopic harvesting.


Subject(s)
Coronary Artery Bypass/methods , Robotics/methods , Thoracic Arteries/surgery , Thoracic Surgery, Video-Assisted/methods , Adult , Feasibility Studies , Humans , Internal Mammary-Coronary Artery Anastomosis/methods , Mammary Arteries/surgery , Middle Aged , Robotics/statistics & numerical data , Thoracic Surgery, Video-Assisted/statistics & numerical data , Time Factors
17.
Ann Cardiol Angeiol (Paris) ; 50(5): 269-73, 2001 Sep.
Article in French | MEDLINE | ID: mdl-12555586

ABSTRACT

OBJECTIVE: Infective endocarditis is always a disease at the present time. In this work we report our initial experience of infective endocarditis surgical treatment during the acute phase. METHODS AND RESULTS: Between September 1993 and December 1997, 13 patients underwent valvular surgery for native infective endocarditis. Mean age was 31 +/- 11 years (range: 9 to 42 years); 92.3% of the patients presented with pre-existing rheumatical valvular lesion. Surgical indication was the occurrence of heart failure in all these patients. Surgery consisted on aortic valvular replacement in four patients, mitral and aortic valvular replacement in nine patients. Tricuspid valvuloplasty was required in two patients. Early mortality was 15% (two patients). A third patient developed cardiac failure and died three years postoperatively. CONCLUSION: This work emphasises the interest of the surgical treatment in the active phase of the infective endocarditis.


Subject(s)
Endocarditis, Bacterial/surgery , Streptococcal Infections/surgery , Adolescent , Adult , Child , Female , Follow-Up Studies , Humans , Male
19.
Immunology ; 99(2): 221-8, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10692040

ABSTRACT

Major histocompatibility complex (MHC) alleles acting as immune response genes are coexpressed in heterozygous individuals and therefore control of immune responses is usually codominant. As an exception to this rule, however, several examples of recessive immune responses have been ascribed to regulatory, e.g. suppressive, interactions. We report here that the recessive phenotype of both antibody and T-cell responses to the mycobacterial 16 000-MW antigen depends critically on a low antigen dose for immunization. On the basis of similar responses in hemi- and heterozygous mice, we suggest that the mechanism of recessive MHC control does not involve regulation by the low-responder allele. We also demonstrated mixed haplotype restriction of peptide recognition for a significant fraction of high-antigen-dose primed T cells. Their paucity under limiting antigen dose conditions may lead to the recessive expression of MHC control. In conclusion, our results suggest that recessive MHC control can be explained as a simple gene dosage effect under conditions where antigen is limiting, without a need for regulatory mechanisms.


Subject(s)
Antigens, Bacterial/administration & dosage , Histones/immunology , Mycobacterium tuberculosis/immunology , Alleles , Animals , Antibodies, Bacterial/biosynthesis , Antigen Presentation , Antigens, Bacterial/immunology , Dose-Response Relationship, Immunologic , Female , Gene Dosage , Haplotypes , Mice , Mice, Inbred C57BL , Mice, Inbred Strains , Peptide Fragments/immunology , T-Lymphocytes/immunology
20.
Parasite Immunol ; 21(8): 383-95, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10417673

ABSTRACT

Specific serum and intestinal immunoglobulin (Ig)G1 and IgA responses to Heligmosomoides polygyrus were measured in a panel of seven inbred mouse strains which exhibit 'rapid' (<6 weeks (SWRxSJL)F1), 'fast' (<8 weeks, SJL and SWR), 'intermediate' (10-20 weeks, NIH and BALB/c) or 'slow' (>25 weeks, C57BL/10 and CBA) resolution of primary infections. Mice with 'rapid', 'fast' or 'intermediate' response phenotypes produced greater serum and intestinal antibody responses than those with 'slow' phenotypes. The F1 hybrids ((SWRxSJL)F1) of two 'fast' responder strains showed the earliest antibody response with maximum titres evident within 6 weeks of infection. There was a negative correlation between the serum IgG1 responses and worm burdens in individual mice within a number of mouse strains, and also between serum IgG1 and IgA responses and worm burdens in the 'rapid' ((SWRxSJL)F1) responder strain. The presence of IgG1 in the gut was found to be due to local secretion rather than plasma leakage. Using Western immunoblotting, serum IgG1 from 'rapid' and 'fast' responder but not 'slow' responder mice was found to react with low molecular weight antigens (16-18 kDa) in adult worm excretory/secretory products.


Subject(s)
Antibodies, Helminth/immunology , Nematospiroides dubius , Strongylida Infections/immunology , Acute Disease , Animals , Antibodies, Helminth/analysis , Antibody Formation/genetics , Antibody Formation/immunology , Antibody Specificity/immunology , Antigens, Helminth/immunology , Chronic Disease , Female , Immunity, Innate , Immunoglobulin A/analysis , Immunoglobulin A/blood , Immunoglobulin A/immunology , Immunoglobulin G/analysis , Immunoglobulin G/blood , Immunoglobulin G/immunology , Immunoglobulin Isotypes/blood , Intestinal Mucosa/parasitology , Intestinal Secretions/immunology , Intestinal Secretions/parasitology , Mice , Mice, Inbred C57BL , Mice, Inbred CBA , Mice, Inbred Strains , Phenotype , Time Factors
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