Nucleic acid distribution pattern in avian erythrocytes and mammalian lymphocytes: comparative studies by fluorescence microscopy and digital imaging analytical techniques.

Nucleated erythrocytes of healthy domestic chicken and ducks, and lymphocytes of healthy Sprague Dawley rats were evaluated for nucleic acid distribution pattern, employing light and fluorescence microscopy procedures, as well as digital imaging analytical methods. The results demonstrate a unique organization of nuclear DNA of mature chicken and duck erythrocytes, as well as immature duck erythrocytes, as delineated spherical nuclear bodies that mostly corresponded with euchromatin zones of the cells in routine Wright-stain blood smears. The nuclear DNA of the rat lymphocytes, on the other hand, was observed as a more diffuse green fluorescing nuclear areas, with punctate variably-sized diffuse areas of RNA red fluorescence. RNA red color fluorescence was also evident in the narrow cytoplasm of the lymphocytes, especially in large lymphocytes, in comparison with the cytoplasm of the mature avian erythrocytes that completely lacked any nucleic acid fluorescence. Nuclear RNA fluorescence was lacking in the mature chicken erythrocytes, compared with those of the mature and immature duck erythrocytes as well as lymphocytes of both avian and rats blood. The significance of these findings lies in the establishment of normal benchmarks for the nuclear and cytoplasmic nucleic acid pattern in eukaryotic cells. These normal benchmarks become valuable in rapid diagnostic situations associated with pathologies, such as the presence of viral nuclear and cytoplasmic inclusion bodies that can alter the nucleic acid pattern of the host cells, and in conditions of cellular abnormal protein aggregations. Variability of cellular nucleic acid pattern can also aid in prognostic assessments of neoplastic conditions.

Nucleic acid distribution pattern in avian erythrocytes and mammalian lymphocytes: comparative studies by fluorescence microscopy and digital imaging analytical techniques.

Nucleated erythrocytes of healthy domestic chicken and ducks, and lymphocytes of healthy Sprague Dawley rats were evaluated for nucleic acid distribution pattern, employing light and fluorescence microscopy procedures, as well as digital imaging analytical methods. The results demonstrate a unique organization of nuclear DNA of mature chicken and duck erythrocytes, as well as immature duck erythrocytes, as delineated spherical nuclear bodies that mostly corresponded with euchromatin zones of the cells in routine Wright-stain blood smears. The nuclear DNA of the rat lymphocytes, on the other hand, was observed as a more diffuse green fluorescing nuclear areas, with punctate variably-sized diffuse areas of RNA red fluorescence. RNA red color fluorescence was also evident in the narrow cytoplasm of the lymphocytes, especially in large lymphocytes, in comparison with the cytoplasm of the mature avian erythrocytes that completely lacked any nucleic acid fluorescence. Nuclear RNA fluorescence was lacking in the mature chicken erythrocytes, compared with those of the mature and immature duck erythrocytes as well as lymphocytes of both avian and rats blood. The significance of these findings lies in the establishment of normal benchmarks for the nuclear and cytoplasmic nucleic acid pattern in eukaryotic cells. These normal benchmarks become valuable in rapid diagnostic situations associated with pathologies, such as the presence of viral nuclear and cytoplasmic inclusion bodies that can alter the nucleic acid pattern of the host cells, and in conditions of cellular abnormal protein aggregations. Variability of cellular nucleic acid pattern can also aid in prognostic assessments of neoplastic conditions.

Post-exposure serological and bacteriological responses of water buffalo (Bubalus bubalis) to Brucella abortus biovar 1 following vaccination with Brucella abortus strain RB51.

Serological and bacteriological responses to Brucella abortus biovar 1 following vaccination with B. abortus strain RB51 (RB51) were evaluated in thirty domestic water buffalo (Bubalus bubalis) randomly divided into five treatment groups. Groups I to V received, respectively, the recommended dose (RD) of RB51 vaccine once, RD twice 4 weeks apart, double RD once, double RD twice 4 weeks apart, and saline once (control). Vaccination did not result in a serological response. Experimental animals released 27 weeks post initial inoculation (27 PIIW) into a brucellosis-positive herd failed to seroconvert after 29 weeks. Experimental challenge commenced at 57 PIIW. All animals received B. abortus biovar 1 intraconjunctivally at 0, 5 and 9 weeks post experimental exposure (PEEW). Serum samples collected at 4, 8 and 13 PEEW were negative. At 16 PEEW all animals received B. abortus biovar 1 subcutaneously (SC), and all seroconverted by 20 PEEW. Five of twenty-six animals were positive for Brucella infection on bacterial culture. Brucella abortus biovar 1 was isolated from three animals; B. abortus RB51 was isolated from two. Treatment group, age and sex had no effect on the isolation of Brucellae (P>0.05).

Post-exposure serological and bacteriological responses of water buffalo (Bubalus bubalis) to Brucella abortus biovar 1 following vaccination with Brucella abortus strain RB51.

Serological and bacteriological responses to Brucella abortus biovar 1 following vaccination with B. abortus strain RB51 (RB51) were evaluated in thirty domestic water buffalo (Bubalus bubalis) randomly divided into five treatment groups. Groups I to V received, respectively, the recommended dose (RD) of RB51 vaccine once, RD twice 4 weeks apart, double RD once, double RD twice 4 weeks apart, and saline once (control). Vaccination did not result in a serological response. Experimental animals released 27 weeks post initial inoculation (27 PIIW) into a brucellosis-positive herd failed to seroconvert after 29 weeks. Experimental challenge commenced at 57 PIIW. All animals received B. abortus biovar 1 intraconjunctivally at 0, 5 and 9 weeks post experimental exposure (PEEW). Serum samples collected at 4, 8 and 13 PEEW were negative. At 16 PEEW all animals received B. abortus biovar 1 subcutaneously (SC), and all seroconverted by 20 PEEW. Five of twenty-six animals were positive for Brucella infection on bacterial culture. Brucella abortus biovar 1 was isolated from three animals; B. abortus RB51 was isolated from two. Treatment group, age and sex had no effect on the isolation of Brucellae (P>0.05).

Serologic responses, biosafety and clearance of four dosages of Brucella abortus strain RB51 in 6-10 months old water buffalo (Bubalus bubalis)

Thirty water buffalo were obtained from a brucellosis-free farm in order to evaluate antibody responses, bacterial clearance and safety to Brucella abortus strain RB51 vaccine in a dose response study. The animals were randomly divided into five treatment groups. Groups I–V received the recommended dose of RB51 vaccine (RD) once, RD twice 4 weeks apart, double RD once, double RD twice 4 weeks apart and saline once, respectively. Antibody responses to RB51 were monitored at 2, 4, 6, 8, 10, 12, 16 18, 22, 24 and 27 post-initial-inoculation weeks (PIW). Clearance of RB51 from the prescapular lymph node was evaluated at 2, 4, 6, 12, 18 and 24 PIW for groups 1, III and V and at 6, 8, 10, 16, 22 and 27 PIW for groups II and IV. To evaluate shedding of the RB51 strain, nasal, conjunctival, vaginal or preputial swabs were taken from all experimental animals at 1, 2, 3, 4, 6, 8 and 12 PIW. Sera taken at all PIW were negative for field strain B. abortus by both the buffered plate agglutination test (BPAT) and competitive enzyme-linked immunosorbent assay (c-ELISA). Antibody responses to RB51 were demonstrated in all vaccinates but not in the controls, up to 12 PIW, by complement fixation test (CFT) and the dot-blot assay with an 83.7% agreement for both tests. Clearance of RB51 occurred between 6 and 12 PIW in group I but less than 2 weeks after booster vaccinations in groups II and IV and between 4 and 6 PIW in group III. RB51 was not recovered at any time from swabs obtained from either RB51-vaccinates or non-vaccinates. The results of this study indicate that serologic responses to RB51 vaccination can be monitored by both CFT and dot-blot assay in water buffalo. Our data also indicates that RB51 vaccination does not interfere with brucellosis sero-surveillance and is safe (no serological and bacteriological evidence of spread to non-vaccinates, no adverse clinical signs or detectable abnormalities on haematology and serum biochemistry) for use in water buffalo (AU)

Serologic responses, biosafety and clearance of four dosages of Brucella abortus strain RB51 in 6-10 months old water buffalo (Bubalus bubalis).

Thirty water buffalo were obtained from a brucellosis-free farm in order to evaluate antibody responses, bacterial clearance and safety to Brucella abortus strain RB51 vaccine in a dose response study. The animals were randomly divided into five treatment groups. Groups I-V received the recommended dose of RB51 vaccine (RD) once, RD twice 4 weeks apart, double RD once, double RD twice 4 weeks apart and saline once, respectively. Antibody responses to RB51 were monitored at 2, 4, 6, 8, 10, 12, 16 18, 22, 24 and 27 post-initial-inoculation weeks (PIW). Clearance of RB51 from the prescapular lymph node was evaluated at 2, 4, 6, 12, 18 and 24 PIW for groups 1, III and V and at 6, 8, 10, 16, 22 and 27 PIW for groups II and IV. To evaluate shedding of the RB51 strain, nasal, conjunctival, vaginal or preputial swabs were taken from all experimental animals at 1, 2, 3, 4, 6, 8 and 12 PIW. Sera taken at all PIW were negative for field strain B. abortus by both the buffered plate agglutination test (BPAT) and competitive enzyme-linked immunosorbent assay (c-ELISA). Antibody responses to RB51 were demonstrated in all vaccinates but not in the controls, up to 12 PIW, by complement fixation test (CFT) and the dot-blot assay with an 83.7% agreement for both tests. Clearance of RB51 occurred between 6 and 12 PIW in group I but less than 2 weeks after booster vaccinations in groups II and IV and between 4 and 6 PIW in group III. RB51 was not recovered at any time from swabs obtained from either RB51-vaccinates or non-vaccinates. The results of this study indicate that serologic responses to RB51 vaccination can be monitored by both CFT and dot-blot assay in water buffalo. Our data also indicates that RB51 vaccination does not interfere with brucellosis sero-surveillance and is safe (no serological and bacteriological evidence of spread to non-vaccinates, no adverse clinical signs or detectable abnormalities on haematology and serum biochemistry) for use in water buffalo.

Screening thoroughbreds for antibodies to the Equine infectious anemia virus.

One hundred and seventy two Thoroughbreds were screened for the presence of anitbodies to the capsid protein, p26 of the equine infectious anemia (EIA)virus using agarose gel immunodiffusion (AGOD) Coggins test. Horses ranged in age from 1 month to 21 years old and were either imported or locally bred. The majority were involved in racing and breeding and were housed either at the Santa Rosa Racing Complex at Arima or at privately owned farms. Complete blood counts (CBCs) were performed on all horses. Low haemoglobin concentrations were found in 18(10.5%), high white blood cell counts in 17 (9.9%) with neutrophilia in 13 (7.6%). Low red blood cell counts were seen in 11 of 154 horses (7.1%). At least 12 horses had evidence of clinical babesiosis, but only 7 were confirmed infected by examination of Giemsa stained blood smears. Racehorses from trinidad and Tobago occasionally move inter-island for racing and increasingly come in contact with foreign horses with the increasing importation of horses from countries known to harbour the virus. All 172 horses tested negative for antibodies to EIA virus. This implies that the strict adherence to import and quarantine regulations may have contributed to keeping the country free from EIA virus. This ongoing study is the first to provide sero-prevalence data and document the prevalence of EIA in the equine population in Trinidad and Tobago.

Screening thoroughbreds for antibodies to the Equine infectious anemia virus.

One hundred and seventy two Thoroughbreds were screened for the presence of anitbodies to the capsid protein, p26 of the equine infectious anemia (EIA)virus using agarose gel immunodiffusion (AGOD) Coggins test. Horses ranged in age from 1 month to 21 years old and were either imported or locally bred. The majority were involved in racing and breeding and were housed either at the Santa Rosa Racing Complex at Arima or at privately owned farms. Complete blood counts (CBCs) were performed on all horses. Low haemoglobin concentrations were found in 18(10.5%), high white blood cell counts in 17 (9.9%) with neutrophilia in 13 (7.6%). Low red blood cell counts were seen in 11 of 154 horses (7.1%). At least 12 horses had evidence of clinical babesiosis, but only 7 were confirmed infected by examination of Giemsa stained blood smears. Racehorses from trinidad and Tobago occasionally move inter-island for racing and increasingly come in contact with foreign horses with the increasing importation of horses from countries known to harbour the virus. All 172 horses tested negative for antibodies to EIA virus. This implies that the strict adherence to import and quarantine regulations may have contributed to keeping the country free from EIA virus. This ongoing study is the first to provide sero-prevalence data and document the prevalence of EIA in the equine population in Trinidad and Tobago.

Evaluation of cell-mediated immune response and bacterial clearance in 6-10 months old water buffalo (Bubalus bubalis) experimentally vaccinated with four dosages of commercial Brucella abortus strain RB51 vaccine

Thirty water buffalo, obtained from a brucellosis-free farm, were used to evaluate cell-mediated immune responses and bacterial clearance in response to vaccination with Brucella abortus strain RB51 (RB51) in a dose-response study. The animals were randomly divided into five treatment groups. Groups I-V received the recommended dose (RD) of RB51 vaccine once, RD twice 4 weeks apart, double RD once, double RD twice 4 weeks apart and saline once, respectively. Cell-mediated immune response to RB51 was assessed by the histological examination of haematoxylin and eosin (H&E) stained sections of lymph nodes draining the sites of inoculation and by comparison of stimulation indices (SI) derived from gamma interferon (IFN-y)assay. A mixture of cytoplasmic proteins from B. melitensis B115 (brucellergene) was used as a specific antigenic stimulus to peripheral blood mononuclear cells (PBMC) and lymph node mononuclear cells (LNMC) up to 22 post-initial-inoculation week (PIW). Supernatants harvested at 18-24 h after the in vitro antigenic stimulus were assayed for their IFN-y content by using a commercial sandwich enzyme-linked immunosorbent assay (ELISA) kit. Clearance of RB51 was assessed by the sequential immunohistochemical examination of sections of draining lymph nodes post-inoculation. There was no observable expansion of the deep cortex of lymph nodes on H&E sections indicating poor T-cell stimulation. All group V (control) water buffalo PBMC ELISA values were negative (SI<2.2) at all PIW sampling intervals. Overall PBMC-IFN-y assay detected vaccinates from treatment groups' I-IV 67 percent (4/6), 83 percent (5/6), 33 percent (2/6) and 67 percent (4/6), respectively. LNMC IFN-y assay was unimpressive and there was a negative correlation (-0.08) between the results of PBMC and LNMC of IFN-y assay. Clearance of RB51 occurred (AU)

Evaluation of cell-mediated immune responses and bacterial clearance in 6-10 months old water buffalo (Bubalus bubalis) experimentally vaccinated with four dosages of commercial Brucella abortus strain RB51 vaccine.

Thirty water buffalo, obtained from a brucellosis-free farm, were used to evaluate cell-mediated immune responses and bacterial clearance in response to vaccination with Brucella abortus strain RB51 (RB51) in a dose-response study. The animals were randomly divided into five treatment groups. Groups I--V received the recommended dose (RD) of RB51 vaccine once, RD twice 4 weeks apart, double RD once, double RD twice 4 weeks apart and saline once, respectively. Cell-mediated immune response to RB51 was assessed by the histological examination of haematoxylin and eosin (H&E) stained sections of lymph nodes draining the sites of inoculation and by comparison of stimulation indices (SI) derived from gamma interferon (IFN-gamma) assay. A mixture of cytoplasmic proteins from B. melitensis B115 (brucellergene) was used as a specific antigenic stimulus to peripheral blood mononuclear cells (PBMC) and lymph node mononuclear cells (LNMC) up to 22 post-initial-inoculation week (PIW). Supernatants harvested at 18-24h after the in vitro antigenic stimulus were assayed for their IFN-gamma content by using a commercial sandwich enzyme-linked immunosorbent assay (ELISA) kit. Clearance of RB51 was assessed by the sequential immunohistochemical examination of sections of draining lymph nodes post-inoculation. There was no observable expansion of the deep cortex of lymph nodes on H&E sections indicating poor T-cell stimulation. All group V (control) water buffalo PBMC ELISA values were negative (SI<2.2) at all PIW sampling intervals. Overall PBMC IFN-gamma assay detected vaccinates from treatment groups' I--IV 67% (4/6), 83% (5/6), 33% (2/6) and 67% (4/6), respectively. LNMC IFN-gamma assay was unimpressive and there was a negative correlation (--.08) between the results of PBMC and LNMC of IFN-gamma assay. Clearance of RB51 occurred between 4 and 6 PIW in treatment groups I and III and between 6 and 12 PIW in groups II and IV. RB51 was not detected in any of the control animals at sampling intervals post-inoculation.

Salmeterol decreases eosinophilic cationic protein and rescue medication in patients inhaling beclomethasone dipropionate: preliminary study in mild and moderate asthma in Trinidad, West Indies.

Activated eosinophils play a critical role in asthma pathogenesis, and eosinophil cationic protein (ECP) is a useful indicator of inflammation. Inhaled corticosteroids and long-acting beta2-agonists (LABA) effectively control asthma symptoms and improve airway function. Salmeterol's anti-inflammatory efficacy as add-on therapy to inhaled corticosteroids has not been evaluated in Caribbean populations. We investigated nine non-smoking subjects (three men and six women; mean age: +/- SE, 50.7 +/- 3.82 years) with stable mild and moderate persistent asthma who were inhaling > or = 500 microg beclomethasone dipropionate (BDP) daily. This was a with-in-patient controlled laboratory blind study performed over 8 weeks. Patients received BDP for 2 weeks, add-on salmeterol 100 microg in weeks 3-6 and BDP alone in weeks 7-8. Patients recorded daily morning and night symptoms. Morning peak expiratory flow rate was measured on entry to the study and with sputum ECP at the end of weeks 2, 4, 6 and 8. Salmeterol together with BDP decreased sputum ECP from a pretreatment median value of 897.84 microg/l to 628.38 microg/l after 4 weeks, and ECP continued to decrease even after salmeterol withdrawal. Both drugs decreased the frequency of rescue medication use by approximately 50% and increased the median number of days per week without rescue salbutamol from 0 to 3 days. Salmeterol's bronchoprotective effect was maximal after 4 weeks and was sustained after its withdrawal. In conclusion, this study, performed in Trinidadian asthmatics, used ECP as a surrogate marker of bronchial inflammation and supports the recent Salmeterol Multi-center Asthma Research Trial (SMART) data recommending add-on salmeterol therapy to adequate anti-inflammatory medication such as inhaled corticosteroids for optimal asthma management. Further studies are required to evaluate the anti-inflammatory efficacy and possible tolerance to salmeterol in Caribbean patients.

Nephrotic syndrome in Trinidadian children.

57 children with idiopathic nephrotic syndrome who were seen at two hospitals in Trinidad between 1989 and 1995 (median follow-up period, 38 months) were classified according to their response to glucocorticoids. 27 (47%) were two to six years old at presentation; 37 (65%) were of East Indian descent, 7 (12%) were of African descent, and 12 (21%) were of mixed race. 55 (96%) responded to glucocorticoids. Renal biopsies in 15 patients revealed membranoproliferative glomerulonephritis and membranous nephropathy in the two patients who had not responded to glucocorticoids. Ten patients showed mesangial hypercellularity, associated with immunoglobulin deposits in 7 cases. Age, presentation with nephrotic features, mesangial hypercellularity and immunoglobulin deposits did not predict for unresponsiveness to glucocorticoids. These findings may be explained by the predominance of East Indians in the study group.