Comparison of techniques of detecting immunoglobulin-binding protein reactivity to immunoglobulin produced by different avian and mammalian species.

The rationale of this study was to use several immunological assays to investigate the reactivity of immunoglobulin binding protein (IBP) to immunoglobulins from various avian and mammalian species. The IBP studied were Staphylococcal protein A (SpA), Streptococcal protein G (SpG), Peptostreptococcal protein L (SpL) and recombinant protein LA (SpLA). The various immunological techniques used were double immunodiffusion (Ouchterlony technique) that tested positive high protein reactivities, direct and competitive enzyme-linked immunosorbent assays (ELISAs) that tested moderate and low positive protein binding capacities, respectively. In addition to sandwich ELISAs, immunoblot analyses and Ig-purification by SpA-affinity chromatography, which were sensitive tests and helpful in the screening and confirmatory tests were also used. The Ouchterlony technique showed that compared to the other proteins, SpLA had the highest range of reactivity with animal sera and purified immunoglobulins while SpL was least reactive. With the direct ELISA, SpL reacted with the raccoon sera, rabbit IgG and with IgY from bantam hens and pigeons. While with the direct ELISA, SpA reacted with sera from skunk, coyote, raccoon, mule, donkey and human. The sandwich ELISA revealed high reactivity of both SpG and SpLA with mammalian sera titres ranging from 1:32 (raccoon serum) to 1:1024 (mule and donkey sera). These results suggest that IBP can be used for the detection of immunoglobulin using various immunological assays and this is important for the diagnosis of infectious diseases in animal and bird populations studied and in the purification of immunoglobulins.

Dengue virus serotypes in Jamaica, 2003-2007.

BACKGROUND: Dengue virus (DENV) infection is increasing in prevalence and severity globally. The severity of dengue is influenced by several factors including the immune response, viral and host genetic factors. METHOD: The DENV serotypes were determined in 770 serum samples from dengue immunoglobulin (Ig) M antibody positive (n = 469), dengue IgM negative (n = 185) and dengue antibody negative (n = 116) patients with suspected dengue who presented during (n = 150) or after (n = 620) the acute phase of illness during 2003-2007. Dengue antibodies were detected by enzyme-linked immunosorbent assays and DENV RNA by reverse transcriptase-polymerase chain reaction (RT-PCR) performed on serum and cell culture supernatants of C6/36 mosquito cells inoculated with acute phase serum (n = 150). RESULTS: Based on serological profiles, 41% of acute phase sera and 66% of post acute sera were from patients with current primary or secondary dengue, while 41% and 35% of acute and post-acute phase sera, respectively, were from patients with secondary dengue or past exposure only. Dengue virus RNA was found in 20/770 samples (2.6%). Only 1.5% (9/620) of sera collected after the acute phase of illness tested positive for DENV RNA compared with 2.6% (4/150) of sera collected during the acute phase and 7.3% of cell culture supernatants inoculated with acute phase serum (11/150, p = 0.001). All four serotypes including DENV-1 (3/20, 15%), DENV-2 (7/20, 35%), DENV-3 (3/20, 15%) and DENV-4 (7/20, 35%) were identified over the five-year period. These results also showed that DENV-1, 2 and 4 were present during 2007 and that DENV-2 and DENV- 4 were the likely causative viruses of the 2007-2008 dengue outbreak in Jamaica. The three strains of DENV-3 were isolated from infants less than three years of age with primary infection during 2006. CONCLUSION: This study highlights the increasing threat of dengue and severe dengue disease to the Jamaican population. Preventative measures including laboratory surveillance and vector control should be strictly maintained at the highest level.

Molecular epidemiology of dengue in Jamaica dengue virus genotypes in Jamaica, 2007.

The genotypes of dengue viruses (DENV) isolated from patients with dengue in Jamaica during 2007 were determined using DNA sequencing and phylogenetic analysis of the C-prM gene junction. The 17 DENV analysed included strains of DENVserotypes 1 (DENV-1, n = 3), DENV-2 (n = 7) and DENV-4 (n = 7). All strains ofDENV-1 were classified as genotype III, while 1 of 7 strains of DENV-2 belonged to the Asian American/Asian genotype, genotype I/III (Jamaica genotype), 2 were genotype V, the American genotype and 4 strains clustered with reference strains belonging to genotype IV. The 6 DENV-4 strains from Jamaica and the control strain clustered together in a separate clade from Caribbean/American reference strains, which belong to genotype II and Asian strains, classified as genotypes I and III. There has been little evolution in the DENV-1 strains circulating in Jamaica over the years and this might reduce the risk of outbreaks due to this serotype. In contrast, the high genetic diversity in strains of DENV-2 viruses in circulation, the presence of more recently introduced genotypes and a new clade of DENV-4 might contribute to the epidemic potential of these DENV serotypes. These preliminary data clearly indicate the need to maintain laboratory surveillance, and other control measures against hyperendemicity of dengue in Jamaica.

Dengue HLA associations in Jamaicans.

BACKGROUND: Polymorphisms in the human leukocyte antigen (HLA) genes might predispose certain individuals to dengue fever (DF) and the severe forms of the disease: dengue haemorrhagic fever/ dengue shock syndrome (DHF/DSS). SUBJECTS AND METHOD: A DNA-based HLA typing method was used to determine the HLA class I and II alleles in 50 patients with dengue, including 45 cases of DF 5 cases of DHF and 177 healthy individuals in Jamaica. RESULTS: HLA-A*24 and - DRbeta5*01/02 were significantly associated with dengue infection while possession of HLA-A*23, -CW*04, -DQbeta*02, -DQbeta*03 and DQbeta*06 were protective. No other significant associations were found after correction for the number of alleles tested at each HLA-locus. CONCLUSION: This is the first study to report a significant association with HLA-A*24 and DF although this allele is associated with DHF and DSS in Vietnamese patients. The other HLA associations observed in the Jamaican cohort also are different from those reported in other ethnic groups. Further studies which involve larger numbers of patients with DHF and explore functional aspects of HLA allelic associations with dengue in Jamaicans are necessary.

Clinical and laboratory features of youth onset type 2 diabetes in Jamaica.

OBJECTIVES: To assess the frequency of youth onset Type 2 diabetes mellitus (T2D) in Jamaica and the characteristics of youth with this form of diabetes. METHODS: Patients from two major referral hospitals, diagnosed with diabetes before age 25 years and < 6 years prior to the study, were evaluated. Classification was based on the presence of GAD-65 and IA-2 diabetes autoantibodies (AB), fasting (FCP) and stimulated C-peptide (SCP) measurements, serum leptin and clinical phenotype as follows: (i) Type IA diabetes--AB+, (ii) Type lB diabetes--AB- and FCP < 230 pmol/l and/or SCP < 660pmol/l, (iii) Type 2 diabetes - AB- and FCP > 500 pmol/L and or SCP 2 1160 pmol/l (iv) Untypeable diabetes--AB- and FCP 230-500 pmol/l and or SCP 660-1160 pmol/l and (v) Lipoatrophic diabetes--clinical phenotype and serum leptin. RESULTS: Fifty-eight participants (21M, 37F, age 20-8 years, duration of diabetes 2.6-2 years) were enrolled in the study. Using the classification criteria, Type 1 diabetes was the most common form of diabetes: 18 (31%) Type 1A, 18 (31%) Type IB. Overall 22% (13 patients) had T2D. Patients with T2D were more likely to be female, older at diagnosis, obese and have a higher blood pressure when compared to those with Type 1 diabetes. In logistic regression analysis, age of diabetes onset, gender BMI, systolic and diastolic blood pressure were significantly associated with T2D. Obesity measured by BMI was the strongest predictor of T2D. CONCLUSIONS: While Type 1 diabetes was the predominant form of diabetes in this study, a significant proportion of Jamaicans with youth onset diabetes may have T2D. Obesity is the strongest clinical predictor of Type 2 diabetes in the young diabetic patient.

High genetic diversity in human immunodeficiency virus-type 1 in Jamaica.

The subtypes of the human immunodeficiency virus - type 1 (HIV-1) strains from 54 HIV-1 - infected persons including 44 strains which were typed previously by heteroduplex mobility assay (HMA) were determined by DNA sequencing and phylogenetic analysis. Of 54 HIV- infected persons, 92.5% were infected with HIV-1 subtype B and 7.5% with other HIV-1 subtypes including subtypes D (3.7%), A (1.9%) and J (1.9%). In the phylogenetic analysis, the subtype A virus found in the sample clustered with subtype A reference strains and a circulating recombinant form (CRF) reference strain which originates in Central Africa and is circulating in Cuba indicating a close relationship between these viruses. There was 86% concordance between HMA and DNA sequencing in assigning subtype B viruses. For the non-B subtype viruses, there was less concordance between the two methods (67%). The results confirm the predominance of HIV-1 subtype B strains and the high genetic diversity of HIV-1 strains in circulation in Jamaica. The efficacies and some limitations of the HMA as a method of HIV-1 subtyping also were noted. It is important that the HIV/AIDS epidemic in Jamaica be monitored meticulously for possible expansions in non-B subtypes and the emergence of inter-subtype recombinant forms. We recommend that the more expensive DNA sequencing and phylogenetic analysis, including HIV-1 genotyping for antiretroviral drug resistance testing, be used as an adjunct to the more cost-effective HMA to track the HIV/AIDS epidemic in Jamaica.

Cardiovascular risk profile in Caribbean youth with diabetes mellitus.

OBJECTIVE: To assess the effect of diabetes mellitus type on conventional and novel cardiovascular risk factors in patients, diagnosed with diabetes from two major referral hospitals in Jamaica, before age 25 years and with diabetes duration < 6 years. METHODS: Participants were classified based on the presence of GAD-65 and IA-2 autoantibodies, C-peptide, leptin and clinical phenotype. Trained observers obtained anthropometric measurements and sitting blood pressure. Fasting blood was taken for glucose, A1c, lipids, high sensitivity C-reactive protein and lipoprotein profile. RESULTS: Fifty-eight participants (21M; 37F age 20 +/- 8 [Mean +/- SD] years, diabetes duration 2.6 +/- 2 years) were enrolled. Thirty-six had Type 1 diabetes (T1D), thirteen Type 2 diabetes (T2D), six were not typed and three had lipoatrophic diabetes. Patients with Type 2 diabetes (T2D) were more obese with a higher systolic blood pressure but a lower A1c than those with Type 1 diabetes (T1D). Total cholesterol, LDL-cholesterol, triglycerides, VLDL, LDL and HDL particle numbers were similar in patients with T1D and T2D. HDL-cholesterol and LDL and HDL particle sizes were lower in patients with T2D but differences were no longer significant after adjusting for BMI. CONCLUSIONS: Risk factors for cardiovascular disease are common in patients with all forms of youth onset diabetes. Clinicians should therefore investigate these risk factors in their patients regardless of diabetes type.

Autoantibodies in Caribbean youth with diabetes mellitus.

The prevalence of diabetes and other autoantibodies in patients with recently diagnosed youth onset diabetes was evaluated. Fifty-seven patients (95% black, age 19 +/- 5 years, 36% male, diabetes duration 2.6 +/- 2.2 years) were clinically diagnosed as having type 1 (n = 35), type 2 (n = 13) and lipoatrophic diabetes (n = 3) while 6 remained untyped. GAD65 was the most common diabetes-associated autoantibody in patients with type 1A diabetes (12/17; 71%). The prevalence of any diabetes-associated autoantibodies decreased with diabetes duration (OR[95%CI]/yr after diagnosis 0.50[0.31,0.82]) and was not associated with age of onset, duration or gender. Rheumatoid factor (13/57; 23%), smooth muscle (6/57; 11%), gastric-parietal cell (5/57; 9%) and thyroid microsomal antibodies (5/57; 9%) were the most frequent non-diabetes associated autoantibodies and were more common in patients with type 1A diabetes. Only one patient had clinical autoimmune disease (hypothyroidism). Type 1A diabetes may constitute up to half the cases of newly diagnosed type 1 diabetes in Jamaican youth and is associated with a higher prevalence of other organ-specific autoantibodies.

Evolving care of HIV-infected pregnant women in Jamaica--from nevirapine to HAART.

BACKGROUND: The Ministry of Health, Jamaica, is scaling-up programmes to improve the health of HIV-positive pregnant women according to the modified WHO recommended preventative mother to child transmission (pMTCT) regimens of therapy based upon the mother's clinical and immunological status. Highly-active antiretroviral drugs (HAART) can result in successful pMTCT to < 1%. We report the clinical and immunological characteristics of HIV/AIDS in an era of evolving treatment and care of HIV-infected pregnant Jamaican women. SUBJECTS AND METHOD: Clinical records were reviewed of patients registered in antenatal clinics in Greater Kingston and St. Catherine, Jamaica (annual birth cohort--20,000) between September 2002 and August 2006. Disease status was determined using the Centers for Disease Control and Prevention (CDC) classification system for adult HIV/AIDS. Demographic, clinical and laboratory data were documented and analyzed. RESULTS: During the four-year period, 571 HIV-infected women were enrolled; 62% from Victoria Jubilee Hospital, 25% from Spanish Town Hospital and 13% from the University Hospital of the West Indies. Mean age was 27-29 (range 15-41) years, median parity was 2 (range 0-9) and 68-70% were unemployed. Ninety-five per cent had live births. CDC categories of illnesses were A--mild disease in 82% (n=473), B--moderate disease in 4.4% (n=24) and C--severe disease in 1.4% (n=8) while 12% (n=66) had insufficient data. During the first three years, CD4+ cell counts were evaluated in only 2.5% (10 of 406) of patients with median of 344 cells/microL, compared to CD4 evaluation in 50% (83 of 165 women) in the last year with median of573 cells/uL. Antiretroviral (ARV) medications primarily for pMTCT were given to 89% (n=506) ofwomen. Of these, uptake of HAART increased during years 1-3 from 2-3% to 62% in year four Within two years post-partum, 24 women died, 92% (n=22)from the direct complications of HIV/AIDS. CONCLUSION: A comprehensive system of care of HIV in the peripartum period has been developed in Jamaica. Detailed medical evaluation during pregnancy is performed with modern guidelines and increasing laboratory availability of CD4+ cell counts and viral loads. We believe declining HIV infection rates in Jamaican infants and healthier mothers are a direct consequence of increased testing in pregnancy with early diagnosis and initiation of HAART-based pMTCT regimens in pregnant women.

Paediatric and perinatal HIV/AIDS in Jamaica an international leadership initiative, 2002-2007.

BACKGROUND: Paediatric and Perinatal HIV/AIDS remain significant health challenges in the Caribbean where the HIV seroprevalence is second only to Sub-Saharan Africa. METHOD: We describe a collaborative approach to the prevention, treatment and care ofHIVin pregnant women, infants and children in Jamaica. A team of academic and government healthcare personnel collaborated to address the paediatric and perinatal HIV epidemic in Greater Kingston as a model for Jamaica (population 2.6 million, HIV seroprevalence 1.5%). A five-point plan was utilized and included leadership and training, preventing mother-to-child transmission (pMTCT), treatment and care of women, infants and children, outcomes-based research and local, regional and international outreach. RESULTS: A core group of paediatric/perinatal HIV professionals were trained, including paediatricians, obstetricians, public health practitioners, nurses, microbiologists, data managers, information technology personnel and students to serve Greater Kingston (birth cohort 20,000). During September 2002 to August 2007, over 69 793 pregnant women presented for antenatal care. During these five years, significant improvements occurred in uptake of voluntary counselling (40% to 91%) and HIV-testing (53% to 102%). Eight hundred and eighty-three women tested HIV-positive with seroprevalence rates of 1-2% each year The use of modified short course zidovudine or nevirapine in the first three years significantly reduced mother-to-child transmission (MTCT) of HIV from 29% to 6% (RR 0.27; 95%0 CI--0.10, 0.68). During 2005 to 2007 using maternal highly active antiretroviral therapy (HAART) with zidovudine and lamivudine with either nevirapine, nelfinavir or lopinavir/ritonavir and infant zidovudine and nevirapine, MTCT was further reduced to an estimated 1.6% in Greater Kingston and 4.75% islandwide. In five years, we evaluated 1570 children in four-weekly paediatric infectious diseases clinics in Kingston, St Andrew and St Catherine and in six rural outreach sites throughout Jamaica; 24% (377) had HIV/AIDS and 76% (1193) were HIV-exposed. Among the infected children, 79% (299 of 377) initiated HAART resulting in reduced HIV-attributable childhood morbidity and mortality islandwide. An outcomes-based research programme was successfully implemented. CONCLUSION: Working collaboratively, our mission of pMTCT of HIV and improving the quality of life for families living and affected by HIV/AIDS in Jamaica is being achieved.

Effectiveness of antiretroviral therapy in treating paediatric HIV/AIDS in Jamaica.

BACKGROUND AND PURPOSE: Paediatric HIV/AIDS remains a significant challenge in developing countries. We describe the effectiveness of interventions in HIV-infected children attending Paediatric Infectious Diseases Clinics in Jamaica. METHODS: One hundred and ninety-seven HIV-infected children were followed prospectively in multicentre ambulatory clinics between September 1, 2002 and August 31, 2005, in the Kingston Paediatric and Perinatal HIV/AIDS Programme, Jamaica, and their outcomes described. RESULTS: Median follow-up was 23 child-months (interquartile range [IQR] 12-31) with 12 children (6.0%) lost to follow-up and deaths (n=13) occurred at 4.64 per 100 child-years of follow-up. Median age was 5.0 years (IQR 2.2-8.1) and 32.1% had Centers for Disease Control and Prevention (CDC) category C disease at enrollment; 62% were ever on antiretroviral therapy (ART) with median duration of 15.4 months (IQR 5.5-25.5); 85% initiated ART with zidovudine/lamivudine/nevirapine. Mean weight-for-height 0.13 +/- 1.02 (mean difference -1.71 [95% Confidence interval (CI) -2.73, -0.69]; p = 0.001) and body mass index-for-age 0.05 +/- 1.11 (mean difference -1.11, [CI -1.79, -0.43]; p = 0.002); z scores increased after 24 months on ART; however, children remained stunted. Reductions in the incidence of hospitalizations (mean diff 30.95, [CI 3.12, 58.78]; p = 0.03) and in episodes of pneumonia, culture-positive sepsis and tuberculosis occurred in those on ART. CONCLUSIONS: A successfully implemented ambulatory model for paediatric HIV care in Jamaica has improved the quality of life and survival of HIV-infected children.

Immunological evidence supporting the use of extracts from Boehmeria jamaicensis Urb for treating the common cold and sinus infections

Mixed lymphocyte responses assays were conducted at 25.0 and 250.0 microg/mL of the crude ethanolic extract of Boehmeria jamaicensis Urb (coded as BJE) using peripheral lymphocytes obtained from individuals suffering from the common cold after four days of infection and from healthy individuals (without the common cold infection). At a concentration of 25 ug/mL, gamma interferon (IFN-gamma) was increased by 24.03 fold and interleukin 4 (IL-4) by 1.71 fold for the cells obtained from individuals with the common cold (Group A). The extract suppressed IFN-gamma by 8.3% while IL-4 was stimulated by 9.90 fold from peripheral lymphocytes obtained from healthy individuals (Group B). Gamma interferon was suppressed at 250 microg/mL while IL-4 was elevated by 1.86 fold for cells obtained from individuals suffering from the common cold (Group A). In conclusion, BJE could have implications for the treatment of the common cold.

Ensayos de reacci¨®n linfocitaria mixta fueron realizados a 25.0 y 250.0 ¦Ìg/mL de extracto etan¨®lico crudo de Boehmeria jamaicensis Urb (codificado como BJE), usando linfocitos perif¨¦ricos obtenidos de individuos con catarro com¨²n luego de cuatro d¨ªas de infecci¨®n, y de individuos sanos (sin la infecci¨®n del catarro com¨²n). Se hall¨® que el interfer¨®n-gamma (IFN-¦Ã) aument¨® en 24.03 veces, y la interleucina 4 (IL-4) en 1.71 veces para las c¨¦lulas obtenidas de individuos con catarro com¨²n, a 25¦Ìg/mL. El extracto inhibi¨® IFN-¦Ã en un 8.3 % en tanto que el IL-4 fue estimulado en 9.90 veces a partirde los linfocitos perif¨¦ricos obtenidos de individuos sanos. El gamma-interfer¨®n fue inhibido a 250 ¦Ìg/mL, mientras que la IL-4 se elev¨® en 1.86 veces para las c¨¦lulas obtenidas de individuos que sufren de catarro com¨²n.

Antinuclear antibodies and HLA class II alleles in Jamaican patients with systemic lupus erythematosus.

OBJECTIVE: The relationship between human leukocyte antigens class II (HLA) and antinuclear antibodies was investigated in Jamaican patients with Systemic Lupus Erythematosus (SLE). METHODS: Samples of blood of 82 patients with SLE and 75 healthy controls were tested for antinuclear antibodies using the fluorescent antinuclear antibody (FANA) test, counterimmunoelectrophoresis (CIEP) and the Crithidia luciliae immunofluorescence test (CL-IFT). A DNA-based HLA typing method was used to determine the frequencies of alleles of HLA-DRB1, DRB3, DRB4 and DRB5 in patients and healthy controls. RESULTS: The FANA test was positive in all of the sera from patients with SLE. Anti-dsDNA antibodies were present in 49% (40/82), anti-Sm/RNP 44% (36/82) and anti-Ro/La 43% (35/82) of the sera from SLE patients. The frequency of HLA-DR4 was significantly lower in SLE patients than in healthy controls (2/82, 2% vs 15/75, 20%; RR = 0.12; p = 0.0004; CP = 0.005) but no other HLA-DRB1 SLE associations were found. A positive HLA-DR3 anti-Ro/La antibody association was found in the patients with SLE (9/21, 43% vs 5/55, 9%; odds ratio (OR) = 7.5; CP = 0.01). In contrast, possession of HLA-DR6 was negatively associated with the absence of anti-dsDNA antibodies (9/32, 28% vs 27/44, 61%; OR = 0.2; CP = 0.05). CONCLUSION: The HLA-DR6 allele is associated with the absence of antinuclear antibodies and HLA-DR3 with the presence of anti-Ro/La antibodies in Jamaican patients with SLE. However, these results and those of previous studies of Jamaican patients suggest that the HLA-DR3 association with the development of SLE reported in other populations might in fact reflect the association of HLA-DR3 with anti-Ro/La antibodies. Further investigations are needed to determine whether HLA-DRB antinuclear antibody associations define clinical subsets of SLE in Jamaican patients.

Antinuclear antibodies and HLA class II alleles in Jamaican patients with systemic lupus erythematosus / Anticuerpos antinucleares y aleles HLA de clase II en pacientes Jamaicanos con lupus eritematoso sistémico

OBJECTIVE: The relationship between human leukocyte antigens class II (HLA) and antinuclear antibodies was investigated in Jamaican patients with Systemic Lupus Erythematosus (SLE). METHODS: Samples of blood of 82 patients with SLE and 75 healthy controls were tested for antinuclear antibodies using the fluorescent antinuclear antibody (FANA) test, counterimmunoelectrophoresis (CIEP) and the Crithidia luciliae immunofluorescence test (CL-IFT). A DNA-based HLA typing method was used to determine the frequencies of alleles of HLA-DRB1, DRB3, DRB4 and DRB5 in patients and healthy controls. RESULTS: The FANA test was positive in all of the sera from patients with SLE. Anti-dsDNA antibodies were present in 49% (40/82), anti-Sm/RNP 44% (36/82) and anti-Ro/La 43% (35/82) of the sera from SLE patients. The frequency of HLA-DR4 was significantly lower in SLE patients than in healthy controls (2/82, 2% vs 15/75, 20%; RR = 0.12; p = 0.0004; CP = 0.005) but no other HLA-DRB1 SLE associations were found. A positive HLA-DR3 anti-Ro/La antibody association was found in the patients with SLE (9/21, 43% vs 5/55, 9%; odds ratio (OR) = 7.5; CP = 0.01). In contrast, possession of HLA-DR6 was negatively associated with the absence of anti-dsDNA antibodies (9/32, 28% vs 27/44, 61%; OR = 0.2; CP = 0.05). CONCLUSION: The HLA-DR6 allele is associated with the absence of antinuclear antibodies and HLA-DR3 with the presence of anti-Ro/La antibodies in Jamaican patients with SLE. However, these results and those of previous studies of Jamaican patients suggest that the HLA-DR3 association with the development of SLE reported in other populations might in fact reflect the association of HLA-DR3 with anti-Ro/La antibodies. Further investigations are needed to determine whether HLA-DRB antinuclear antibody associations define clinical subsets of SLE in Jamaican patients.

OBJETIVO Se investigó la relación entre los antígenos de leucocito humano (human leukocyte antigens o HLAs). Clase II y los anticuerpos antinucleares en pacientes jamaicanos con lupus eritematoso sistémico (LES). MÉTODOS: Se examinaron muestras de sangre de 82 pacientes con LES y 75 controles saludables para determinar la presencia de anticuerpos antinucleares, usando la prueba del anticuerpo antinuclear fluorescente (FANA), la contrainmunoelectroforesis (CIEP) y el test de inmunofluorescencia con Crithidia luciliae (CL-IFT). Un método de tipificación HLA basado en el ADN fue usado para determinar las frecuencias de aleles de HLA-DRB1, DRB3, DRB4 y DRB5 tanto en los pacientes como en los controles saludables. RESULTADOS: La prueba FANA fue positiva en todos los sueros de pacientes con LES. Anticuerpos anti-dsADN se hallaban presentes en 49% (40/82), anti-Sm/RNP en 44% (36/82) y anti-Ro/La en 43% (35/82) de los sueros de los pacientes de LES. La frecuencia de HLA-DR4 fue significativamente más baja en los pacientes con LES que en los controles saludables (2/82, 2% vs 15/75, 20%; RR = 0.12; p = 0.0004; CP = 0.005) pero no se hallaron otras asociaciones de LES con HLA-DRB1. Se halló una asociación positiva de anticuerpos HLA-DR3 anti-Ro/La en los pacientes con LES (9/21, 43% vs 5/55, 9%; odds ratio (OR) = 7.5; CP = 0.01). En contraste con ello, la posesión de HLA-DR6m estuvo asociada negativamente con la ausencia de anticuerpos anti-dsADN (9/32, 28% vs 27/44, 61%; OR = 0.2; CP = 0.05). CONCLUSIÓN: El alele HLA-DR6 está asociado con la ausencia de anticuerpos antinucleares y el de HLA-DR3 con la presencia de anticuerpos anti-Ro/La en pacientes jamaicanos con LES. Sin embargo, estos resultados al igual que los de los previos estudios de pacientes jamaicanos, sugieren que la asociación HLA-DR3 con el desarrollo de LES reportado en otras poblaciones podría de hecho reflejar la asociación de HLA-DR3 con anticuerpos anti-Ro/La. Se requieren investigaciones ulteriores a fin de determinar si las asociaciones de anticuerpo antinuclear HLA-DRB definen subconjuntos de LES en pacientes jamaicanos.

Immunological evidence supporting the use of extracts from Boehmeria jamaicensis Urb for treating the common cold and sinus infections.

Mixed lymphocyte responses assays were conducted at 25.0 and 250.0 microg/mL of the crude ethanolic extract of Boehmeria jamaicensis Urb (coded as BJE) using peripheral lymphocytes obtained from individuals suffering from the common cold after four days of infection and from healthy individuals (without the common cold infection). At a concentration of 25 ug/mL, gamma interferon (IFN-gamma) was increased by 24.03 fold and interleukin 4 (IL-4) by 1.71 fold for the cells obtained from individuals with the common cold (Group A). The extract suppressed IFN-gamma by 8.3% while IL-4 was stimulated by 9.90 fold from peripheral lymphocytes obtained from healthy individuals (Group B). Gamma interferon was suppressed at 250 microg/mL while IL-4 was elevated by 1.86 fold for cells obtained from individuals suffering from the common cold (Group A). In conclusion, BJE could have implications for the treatment of the common cold.

The immunomodulatory effect of antibiotics on the secretion of tumour necrosis factor alpha by peripheral blood mononuclear cells in response to Stenotrophomonas maltophilia stimulation.

Some antibiotics have been shown to modify the host immune response. Infection with Stenotrophomonas maltophilia, is often difficult to treat due to multiresistance to antibiotics. The authors examined the effect of four commonly used antimicrobial agents (ciprofloxacin, ceftazidime, cotrimoxazole and piperacillin-tazobactam) on tumour necrosis factor alpha (TNF alpha) production by human peripheral blood mononuclear cells (PBMC) stimulated with heat-killed S maltophilia. Cotrimoxazole was the only antibiotic that suppressed TNFa secretion at clinically achievable concentrations. This may explain its use with good effect in the treatment of S maltophilia infections. However at supratherapeutic concentrations, ceftazidime and ciprofloxacin, but not piperacillin-tazobactam, also inhibited significantly the production of TNF alpha. Cotrimoxazole, in addition to its antimicrobial effect against S maltophilia, has an immunomodulatory effect on peripheral blood mononuclear cells stimulated by S maltophilia.

Epidemiology of coagulase-negative Staphylococci isolated from clinical blood specimens at the University Hospital of the West Indies.

The prevalence and significance of coagulase negative staphylococci (CoNS) isolated from blood cultures at the University Hospital of the West Indies (UHWI) during a six-month period were investigated. Standard and automated microbiological procedures were used to process 3001 blood culture specimens received from 2363 patients and 658 (21.9%) of the blood cultures yielded 854 bacterial isolates. The highest prevalence of positive blood cultures (60%) and the lowest prevalence of blood isolates of CoNS (12%) were found in the intensive care unit (ICU). The blood isolates of CoNS were most frequent in the surgical wards (13%) and lowest in obstetrics and gynaecology (2%). High rates of resistance to methicillin, other anti-staphylococcal penicillins, and cephalosporins used in the treatment of CoNS were observed All blood isolates of CoNS (100%) were susceptible to vancomycin. In conclusion, the results show that coagulase-negative staphylococci are the most prevalent bacterial isolates in blood cultures at the UHWI occurring mostly as contaminants. The practice of proper venepuncture and hand-washing techniques by medical staff are recommended to facilitate appropriate antibiotic usage.