Performance, health, and physiological responses of newly received feedlot cattle supplemented with pre- and probiotic ingredients

Nutritional strategies that optimize immunity of feedlot cattle are warranted due to increasing regulations with the use of feed-grade antimicrobials. This study evaluated physiological, health, and performance responses of cattle receiving a synbiotic supplement (yeast-derived prebiotic + Bacillus subtilis probiotic), which replaced feed-grade antimicrobials or were fed in conjunction with monensin during the initial 45 days in the feedlot. Angus-influenced steers (n = 256) were acquired from an auction facility on day -2, and transported (800 km) to the feedlot. Shrunk BW was recorded upon arrival (day -1). Steers were allocated to 1 of 18 pens (day 0), and pens were assigned to receive (n = 6/treatment) a free-choice diet containing: (1) monensin and tylosin (RT; 360 mg/steer daily from Rumensin and 90 mg/steer daily from Tylan; Elanco Animal Health, Greenfield, IN, USA), (2) yeast-derived ingredient and B. subtilis probiotic (CC; 18 g/steer daily of Celmanax and 28 g/steer daily of Certillus; Church and Dwight Co., Inc., Princeton, NJ, USA), or (3) monensin in addition to yeast-derived and B. subtilis ingredients (RCC) as in RT and CC. Steers were assessed for bovine respiratory disease (BRD) and DMI daily. Steer BW was recorded on days 45 and 46, and averaged for final BW. Blood samples were collected on days 0, 7, 17, 31, and 45. Feed intake was greater (P ≤ 0.05) in CC vs. RCC and RT during the initial 3 weeks upon feedlot arrival. No treatment differences were noted (P ≥ 0.41) for average daily gain, BW, and feed efficiency. Incidence of BRD did not differ (P = 0.77) between treatments (average 80.1%). A greater proportion (P ≤ 0.03) of RT steers diagnosed with BRD required a second antimicrobial treatment compared with CC and RCC (57.3, 37.3, and 38.6%, respectively). Removal of steers from the trial due to severe morbidity + mortality was greater (P = 0.02) in RT vs. CC (22.4 and 7.0%), and did not differ (P ≥ 0.16) among RCC (12.9%) vs. RT and CC. Plasma glucose concentrations were greater (P ≤ 0.02) in CC vs. RCC and RT on day 7. Plasma concentrations of nonesterified fatty acids were greater (P ≤ 0.02) in RT and RCC vs. CC on day 7, and in RT vs. CC on day 17. Steers receiving the synbiotic supplement had improved response to BRD treatment, suggesting heightened immunocompetence from partially enhanced metabolism and the nutraceutical effects of B. subtilis and yeast compounds.

Dengue Virus Serotype 2 Intrahost Diversity in Patients with Different Clinical Outcomes

Intrahost genetic diversity is thought to facilitate arbovirus adaptation to changing environments and hosts, and it might also be linked to viral pathogenesis. Dengue virus serotype 2 (DENV-2) has circulated in Brazil since 1990 and is associated with severe disease and explosive outbreaks. Intending to shed light on the viral determinants for severe dengue pathogenesis, we sought to analyze the DENV-2 intrahost genetic diversity in 68 patient cases clinically classified as dengue fever (n = 31), dengue with warning signs (n = 19), and severe dengue (n = 18). Unlike previous DENV intrahost diversity studies whose approaches employed PCR, here we performed viral whole-genome deep sequencing from clinical samples with an amplicon-free approach, representing the real intrahost diversity scenario. Striking differences were detected in the viral population structure between the three clinical categories, which appear to be driven mainly by different infection times and selection pressures, rather than being linked with the clinical outcome itself. Diversity in the NS2B gene, however, showed to be constrained, irrespective of clinical outcome and infection time. Finally, 385 non-synonymous intrahost single-nucleotide variants located along the viral polyprotein, plus variants located in the untranslated regions, were consistently identified among the samples. Of them, 124 were exclusively or highly detected among cases with warning signs and among severe cases. However, there was no variant that by itself appeared to characterize the cases of greater severity, either due to its low intrahost frequency or the conservative effect on amino acid substitution. Although further studies are necessary to determine their real effect on viral proteins, this heightens the possibility of epistatic interactions. The present analysis represents an initial effort to correlate DENV-2 genetic diversity to its pathogenic potential and thus contribute to understanding the virus’s dynamics within its human host.

Impact of 24-h feed or water, or both, deprivation on feed intake, metabolic, and inflammatory response in beef heifers

This experiment evaluated the effects of 24-h feed or water, or both, restriction on hay intake, metabolic, and inflammatory response in growing beef heifers. Forty Angus × Hereford heifers were ranked by initial body weight (BW) (275 ± 6 kg) and age (278 ± 6 d) and randomly allocated to 20 drylot pens (two heifers per pen) in 5, consecutively run, 4 × 4 Latin squares containing four periods of 17 d each. From days 5 to 0 of each period, all pens were offered alfalfa-grass hay ad libitum plus 454 g of dried distillers' grains with solubles (as-fed basis) per heifer/d. On day 0 of each period, pens received one of the four treatments: 1) feed and water restriction for 24 h (FWR), 2) feed restriction for 24 h (FR), 3) water restriction for 24 h (WR), or 4) full access to feed and water (CON). Treatments were concurrently applied from days 0 to 1. Heifer full BW was collected for two consecutive days (days 6 and 5), before (day 0) and after (day 1) treatment application, and on days 3, 6, and 10 of each period. Hay dry matter intake was recorded daily from days 5 to 10. Blood was collected on days 5, 0, 1, 3, 6, and 10 of each experimental period. Following treatment on day 1, BW loss was greater, and heifer BW was less (P < 0.01), for WR, FWR, and FR compared with CON, whereas similar (P > 0.13) for BW loss and heifer BW among heifers that received nutrient restriction. No treatment effects were detected (P = 0.88) for overall ADG. Plasma cortisol concentration was greater (P < 0.01) in FR and FWR vs. WR and CON on day 1, and similar (P = 0.46) between CON and WR. Serum NEFA concentration was greater (P < 0.01) in FR and FWR vs. WR and CON on day 1, and also greater (P < 0.01) in WR vs. CON heifers on day 1. No treatment effects were detected (P = 0.53) for plasma haptoglobin concentration. Hence, feed or water, or both, restriction for 24 h did not affect hay intake and ADG, whereas metabolic results suggest that nutrient deprivation is the major contributor to the increased cortisol and NEFA response of growing beef heifers.

Effects of supplementing calcium salts of polyunsaturated fatty acids to late-gestating beef cows on performance and physiological responses of the offspring

This experiment compared performance and physiological responses of the offspring from cows supplemented with Ca salts of PUFA or SFA + MUFA during late gestation. Ninety-six multiparous, nonlactating, pregnant Angus × Hereford cows were ranked by BW, BCS, and age and divided into 24 groups of 4 cows/group at the end of their second trimester of gestation (d -7). Cows conceived during the same estrus synchronization + AI protocol, with semen from a single sire; hence, gestation length was 195 d for all cows at the beginning of the experiment (d 0). Groups were randomly assigned to receive (DM basis) 405 g/cow daily of soybean meal in addition to 1) 190 g/cow daily of Ca salts of PUFA based on eicosapentaenoic, docosahexaenoic, and linoleic acids or 2) 190 g/cow daily of Ca salts of SFA + MUFA based on palmitic and oleic acids (CON). Groups were maintained in 2 pastures (6 groups of each treatment/pasture) and received daily 10.1 kg/cow (DM basis) of grass-alfalfa hay. Groups were segregated into 1 of 12 drylot pens (6 by 18 m) and individually offered treatments 3 times/wk from d 0 until calving. Cow BW and BCS were recorded, and blood samples were collected on d -7 of the experiment and also within 12 h after calving. Calf BW was also recorded within 12 h of calving. Calves were weaned on d 280 of the experiment, preconditioned for 45 d (d 280 to 325), transferred to a growing lot on d 325, and moved to a finishing lot on d 445, where they remained until slaughter. At calving, PUFA-supplemented cows had a greater ( < 0.01) proportion (as % of total plasma fatty acids) of PUFA, including linoleic, linolenic, arachidonic, docosapentaenoic, and docosahexaenoic acids. At weaning, calves from CON-supplemented cows were older ( = 0.03), although no treatment differences were detected ( = 0.82) for calf weaning BW. During both growing and finishing phases, ADG was greater ( ≤ 0.06) in calves from PUFA-supplemented cows. Upon slaughter, HCW and marbling were also greater ( ≤ 0.05) in calves from PUFA-supplemented cows. Collectively, these results indicate that supplementing eicosapentaenoic, docosahexaenoic, and linoleic acids to late-gestating beef cows stimulated programming effects on postnatal offspring growth and carcass quality. Therefore, supplementing late-gestating beef cows with Ca salts of PUFA appears to optimize offspring productivity in beef production systems.

Effects of supplemental calcium salts of palm oil and chromium-propionate on insulin sensitivity and productive and reproductive traits of mid- to late-lactating Holstein × Gir dairy cows consuming excessive energy

This experiment compared insulin sensitivity, milk production, and reproductive outcomes in dairy cows consuming excessive energy during mid to late lactation and receiving in a 2 × 2 factorial design (1) concentrate based on ground corn (CRN; n = 20) or including 8% (DM basis) of Ca salts of palm oil (CSPO; n = 20), and (2) supplemented (n = 20) or not (n = 20) with 2.5 g/d of Cr-propionate. During the experiment (d 0-203), 40 multiparous, nonpregnant, lactating 3/4 Holstein × 1/4 Gir cows (initial days in milk = 81 ± 2; mean ± SE) were offered corn silage for ad libitum consumption, and individually received concentrate formulated to allow diets to provide 160% of their daily net energy for lactation requirements. From d -15 to 203, milk production was recorded daily, blood samples collected weekly, and cow body weight (BW) and body condition score (BCS) recorded on d 0 and 203. For dry matter intake evaluation, cows from both treatments were randomly divided in 5 groups of 8 cows each, and allocated to 8 individual feeding stations for 3 d. Intake was evaluated 6 times/group. Glucose tolerance tests (GTT; 0.5 g of glucose/kg of BW) were performed on d -3, 100, and 200. Follicle aspiration for in vitro embryo production was performed via transvaginal ovum pick-up on d -1, 98, and 198. Mean DMI, net energy for lactation intake, as well as BW and BCS change were similar across treatments. On average, cows gained 40 kg of BW and 0.49 BCS during the experiment. Within weekly blood samples, CRN cows had lower serum concentrations of glucose, insulin, fatty acids, and insulin-to-glucose ratio compared with CSPO cows, suggesting increased insulin sensitivity in CRN cows. During the GTT, insulin-sensitivity traits were also greater in CRN versus CSPO cows. Supplemental Cr-propionate resulted in lower serum insulin concentrations and insulin-to-glucose ratio within CRN cows only, indicating that Cr-propionate improved basal insulin sensitivity in CRN but not in CSPO cows. During the GTT, however, Cr-propionate supplementation reduced hyperinsulinemia and insulin-to-glucose ratio across CSPO and CRN cows. Milk production, as well as number of viable oocytes collected and embryos produced within each aspiration, were not affected by treatments. Hence, replacing corn by Ca salts of palm oil in the concentrate did not improve insulin sensitivity in Holstein × Gir dairy cows consuming excessive energy during mid to late lactation, whereas Cr-supplementation was effective in improving basal insulin sensitivity in cows not receiving Ca salts of palm oil.

Physiologic, health, and production responses of dairy cows supplemented with an immunomodulatory feed ingredient during the transition period

This study compared physiological, health, and productive parameters in dairy cows supplemented or not with Omnigen-AF (OMN; Phibro Animal Health, Teaneck, NJ) during the transition period. Thirty-eight nonlactating, multiparous, pregnant Holstein × Gir cows were ranked by body weight (BW) and body condition score (BCS), and assigned to receive (n=19) or not (CON; n=19) OMN at 56 g/cow daily (as-fed basis) beginning 35 d before expected date of calving. Before calving, cows were maintained in single drylot pen with ad libitum access to corn silage, and received (as-fed basis) 3kg/cow daily of a concentrate. After calving, cows were moved to an adjacent drylot pen, milked twice daily, offered (as-fed basis) 35kg/cow daily of corn silage, and individually received a concentrate formulated to meet their nutritional requirements after both milkings. Cows received OMN individually as top-dressing in the morning concentrate feeding. Before calving, cow BW and BCS were recorded weekly and blood samples were collected every 5 d beginning on d -35 relative to expected calving date. After calving and until 46 d in milk, BW and BCS were recorded weekly, individual milk production was recorded, and milk samples were collected daily for total solids and somatic cell count analyses. Blood was sampled daily from 0 to 7 d in milk, every other day from 9 to 21 d in milk, and every 5 d from 26 to 46 d in milk. On 30 and 46 d in milk, cows were evaluated for endometritis via cytobrush technique, based on % of polymorphonuclear (PMN) cells in 100 total cell count (PMN + endometrial cells). On 48.7±1.6 d in milk, 9 cows/treatment received a lipopolysaccharide (LPS) injection (0.25μg/kg of BW), and blood was sampled hourly from -2 to 8 h, at 12-h intervals from 12 to 72 h, and at 24-h intervals form 96 to 120 h relative to LPS administration. No treatment differences were detected on BW, BCS, serum concentrations of cortisol, fatty acids, insulin, glucose, haptoglobin, cortisol, and insulin-like growth factor-I. Cows receiving OMN had greater milk yield (30.3 vs. 27.1kg/d) and percentage of PMN cells in endometrial cell population (12.2 vs. 3.9%) compared with CON cows. After LPS administration, cows receiving OMN had greater mean serum haptoglobin (212 vs. 94 µg/mL), as well as greater serum concentration of tumor necrosis factor α at 1, 2, and 3 h relative to LPS injection compared with CON cows. In conclusion, OMN supplementation during the transition period enhanced innate immunity parameters and increased milk production in dairy cows.

Immunogenicity of a 23-valent pneumococcal polysaccharide vaccine in Brazilian elderly

Serum antibodies specific for the capsular polysaccharides of Streptococcus pneumoniae provide protection against invasive pneumococcal infection. In Brazil, this vaccine has been used for people over 65 years with clinical risk to develop pneumococcal infection since 1999. We evaluated the immune response of 102 elderly subjects (75.5% females and 24.5% males) with a mean age of 71 years, and 19 young healthy adults (63.2% females and 36.8% males) with a mean age of 27 years. The elderly study group consisted of outpatients who received follow-up care in the Geriatric Department of General Hospital, Faculty of Medicine, University of São Paulo. None had acute illness at the time of vaccination. Both groups were immunized with one intra-deltoid injection with 0.5 ml of a 23-valent pneumococcal polysaccharide vaccine. The total IgG specific antibody concentrations to capsular polysaccharides 1, 3, 5, 6B, 8, and 14 were determined against pre- and 1-month post-vaccination sera. All samples were analyzed according to the second-generation pneumococcal polysaccharide ELISA protocol. We observed that the pneumococcal polysaccharide vaccine evoked consistent antibody increase for serotypes 1, 5, 6B, 8, and 14 (geometric mean concentration increase of 2.46 in the elderly and 2.84 in the young adults). Otherwise, we observed no increase in antibody concentration for serotype 3 in both groups.

Early blood pressure level as a mark of familial aggregation of metabolic cardiovascular risk factors--the Rio de Janeiro Study

OBJECTIVE

To investigate the familial aggregation of metabolic risk factors (RF) according to blood pressure (BP) percentile of children and adolescents.

DESIGN AND METHODS

Normal BP was established in 3906 children and adolescents in 1987. From this population two groups of target individuals were separated: group A (n = 327) with systolic and/or diastolic BP percentile > 95 and group B (n = 327) with systolic and diastolic BP percentile < or = 50. Ten years later, familial aggregation of metabolic RF was evaluated using clinical and laboratorial data from 785 individuals, divided into two groups: group 1 with 135 target individuals (BP percentile > 95), 181 parents, 100 siblings and 16 grandparents; and group 2: 106 target individuals (BP percentile < or = 50), 145 parents, 84 siblings and 18 grandparents.

RESULTS

(1) The longitudinal study 10 years later (tracking effect) showed that 34.8% of target individuals of group 1 and 90.5% of group 2 remained at the same BP percentile. (2) Comparing the two groups of target individuals, group 1 had higher weight and body mass index (BMI), systolic BP (SBP), diastolic BP (DBP), and heart rate (HR) (P < 0.001) and lower HDL (P < 0.003). (3) Comparing target individuals' and their relatives' measurements together, group 1 had higher BMI, HR, SBP, DBP (P < 0.03) and lower HDL (P < 0.001). (4) SBP and DBP showed significant correlation with all metabolic variables even when BMI was controlled in a multiple regression analysis (P < 0.04).

CONCLUSION

BP level in children and adolescents was a good marker for familial aggregation of metabolic RF, suggesting an interaction of genetic and environmental factors. Primary intervention should be carried out in early stages of life.

Macroscopic agglutination test for rapid diagnosis of human leptospirosis

A commercially available slide agglutination test (SAT) for the diagnosis of human leptospirosis was evaluated by comparing it to an immunoglobulin M (IgM) enzyme-linked immunosorbent assay (ELISA) and to the microscopic agglutination test (MAT). For all 108 patients, leptospirosis was diagnosed on the basis of a fourfold or greater increase in titer by MAT (seroconversion), and all but 1 of 245 controls were MAT negative (titers, <1:100). Both SAT and the IgM ELISA failed to detect one case of infection (sensitivity, 99%). Only 3 of 145 blood donors and none of the 100 patients with other illnesses were SAT positive (specificity, 99%). The overall results were similar for the three tests; however, SAT and ELISA were statistically more sensitive as initial screening tests. For 22% of the patients, the diagnosis of leptospirosis was made earlier by SAT than by MAT. SAT detected 27 (44%) of 62 MAT-negative patients with the first serum sample. ELISA and SAT had very similar results. Follow-up of patients for 1 year after the onset of symptoms showed a decreasing rate of positivity by SAT from the third month on. The rate of positivity by ELISA decreased more slowly, to about 67% by the end of the study. By MAT all patients were persistently reactive. SAT and ELISA seem to be convenient methods for the rapid and early screening for leptospirosis and could replace the less sensitive MAT. ELISA gives less subjective results than SAT and provides information on IgM kinetics, but it can be performed only by the more sophisticated laboratories. SAT is inexpensive, can be performed more quickly and more easily than ELISA, and could be used by the less well equipped laboratories.

Hyperglycemia, hyperinsulinemia, overweight, and high blood pressure in young adults: the Rio de Janeiro Study

Children and adolescents (n=3906, 10-15 years old) have been participating in a screening program for high blood pressure. Sixty-four individuals (17-23 years old) from this population were followed up for 8 years and four consecutive screenings and were stratified into three groups according to blood pressure: group 1 (n=23), > or = 95th percentile for at least three of four evaluations; group 2 (n=28), < 50th percentile for at least three of four screenings; and group 3 (n=13), with unstable blood pressure percentiles. All 64 individuals underwent an oral glucose tolerance test after a 12-hour fast. Blood samples were collected at 0, 30, 60, 90, and 120 minutes for insulin and glucose measurements. Group 1 had a greater body mass index and higher systolic and diastolic blood pressures, basal glucose and insulin levels, and peak values of insulin and glucose levels than the other groups (P<.05). Group 1 also had a higher prevalence of overweight and abnormal values of basal insulin than the other groups (P<.05) and a higher proportion of glucose-intolerant individuals when compared with group 2 (P<.05). Systolic and diastolic blood pressures were positively related to body mass index (P<.05) and insulin variables (P<.05); however, when body mass index was controlled for, only systolic blood pressure demonstrated a significant correlation with insulin variables (P<.05). The association of overweight, hyperinsulinemia, glucose intolerance, and high blood pressure can be detected early, but the significance of these findings would be better explained by longitudinal studies.

Evaluation of diagnostic tests for human leptospirosis

The IgM-PK-ELISA, an enzyme-linked immunosorbent assay for immunoglobulin M employing a proteinase K-treated antigen, and the "Leptoteste-S" macroagglutination test were evaluated for use in a rapid serodiagnosis of human leptospirosis. The microscopic agglutination test (MAT) was used as reference. The three serological tests were applied to serum samples from patients with leptospirosis (N = 89), typhoid fever (N = 8), malaria (N = 19), syphilis (N = 20), hepatitis (N = 16) and from clinically healthy donors (N = 92). The overall results of the IgM-PK-ELISA and the "Leptoteste-S" are comparable to those of the MAT. However, both tests differed statistically from MAT in terms of the positivity of the acute-phase sera, with approximately 38% of the patients with leptospirosis being identified earlier than when MAT was used. The IgM-PK-ELISA, with 89.9% sensitivity and 97.4% specificity, could be the test of choice for those laboratories which are equipped to perform ELISA. The "Leptoteste-S", with 89.9% sensitivity and 94.8% specificity, seems to be easier to perform and the most accessible to peripheral laboratories for rapid screening of human sera. Both techniques present the important characteristic of detecting early antibodies against leptospires, thus providing a diagnosis during the early stages of the disease.

Role of anthropometric indexes and blood pressure as determinants of left ventricular mass and geometry in adolescents. The Rio de Janeiro Study

To evaluate left ventricular structural changes and their relationship to blood pressure and anthropometric indexes, we examined by echocardiography 108 adolescents aged 13 to 19 years. Subjects were divided into three groups according to blood pressure tracking during three moments of observation: group 1 (n = 27), > or = 95th percentile; group 2 (n = 37), < or = 50th percentile; and group 3 (n = 44), blood pressure not stable in the original percentile. Left ventricular mass index and the prevalence of altered left ventricular geometry were greater in group 1 (P < .05 and P < .02, respectively). Of all the anthropometric indexes, body surface area showed the best correlation with left ventricular mass (P < .00001). Left ventricular mass also correlated with systolic and diastolic pressures (P < .00001 and P < .003, respectively). Ventricular septal and posterior wall thicknesses and left ventricular diastolic diameter showed good correlations with body surface area (P < .00001). These variables also correlated with systolic pressure (P < .001). In a multiple regression model when body surface area was controlled, systolic pressure did not correlate significantly with left ventricular mass. In a similar model systolic pressure maintained a significant correlation with ventricular septal and posterior wall (P < .00001) thicknesses but not with left ventricular diastolic diameter (P > .05). We conclude that left ventricular structural changes can occur early after initial abnormalities of blood pressure. Considering that body surface area and systolic pressure were the best predictors of left ventricular alterations in adolescents, the usual way of correcting left ventricular mass by body surface area should be reviewed.

Behaviour of specific IgM, IgG and IgA class antibodies in human leptospirosis during the acute phase of the disease and during convalescence

The behaviour of specific IgM, IgG and IgA class antibodies in human leptospirosis was studied by ELISA. Two groups of patients were followed up, 57 of them in the acute phase and 10 during convalescence, the latter with a mean follow-up of 10.5 months. IgM class antibodies were detected starting on the 2nd day of symptoms and were observed in 100% of patients up to the 5th month, in 66.7% up to the 7th month and in 50% up to the 12th month after the onset of symptoms. IgG class antibodies were first detected on the 7th day of symptoms in 9.1% of patients, with maximum reactivity (87.5%) between the 2nd and 3rd month, and were not detected at all in one patient. IgA class antibodies were detected starting on the 5th day of symptoms in 7.7% of patients, and in all patients on the 15th day, persisting in 100% of cases up to the 9th follow-up month. During the 12th month, they were observed in 83.3% of patients. The results indicate that an anti IgA ELISA could be of great value in seroprevalence studies on human leptospirosis.

[Multicenter National Study for the evaluation of the efficacy and tolerance of nifedipine oral release osmotic system in mild to moderate hypertension]

PURPOSE

Evaluation of the efficacy and tolerability of nifedipine oros in patients with mild to moderate essential hypertension without major target organ damage and the anti-hypertensive effect along the 24 hours.

METHODS

Two hundred and three patients were studied. After two weeks placebo running period single dose of nifedipine oros (30 mg/day) was administered for 8 weeks. At the end of the 4th week, the non-responders (diastolic blood pressure > 90 mmHg or reduction in diastolic pressure < 10 mmHg), had the dosage increased to 60 mg/day. Laboratory tests and 24h blood pressure monitoring (60 patients) were performed at the beginning and at the end of the study.

RESULTS

One hundred and ninety one patients completed the study. Fifty nine percent were considered responders at the end of the 4th week with nifedipine oros 30 mg/day and 41% needed dosage increment to 60 mg/day. At the end of the 8th week, all patients were considered responders to nifedipine oros. The blood pressure control extended throughout the 24h of the day. The most common adverse events were edema (14.6%) and headache (12.4%). Good and very good tolerability were informed by 85% of the patients.

CONCLUSION

Nifedipine oros was able to control blood pressure efficaciously along the 24h period without important side effects. The possibility of once day dosage, increases the patient adherence to anti-hypertensive therapy.

Dot-ELISA-IgM in saliva for the diagnosis of human leptospirosis using polyester fabric-resin as support (preliminary report)

In order to improve the diagnosis of human leptospirosis, we standardized the dot-ELISA for the search of specific IgM antibodies in saliva. Saliva and serum samples were collected simultaneously from 20 patients with the icterohemorrhagic form of the disease, from 10 patients with other pathologies and from 5 negative controls. Leptospires of serovars icterohaemorrhagiae, canicola, hebdomadis, brasiliensis and cynopteri grown in EMJH medium and mixed together in equal volumes, were used as antigen at individual protein concentration of 0.2 micrograms/microliters. In the solid phase of the test we used polyester fabric impregnated with N-methylolacrylamide resin. The antigen volume for each test was 1 microliter, the saliva volume was 8 microliters, and the volume of peroxidase-labelled anti-human IgM conjugate was 30 microliters. A visual reading was taken after development in freshly prepared chromogen solution. In contrast to the classic nitrocellulose membrane support, the fabric support is easy to obtain and to handle. Saliva can be collected directly onto the support, a fact that facilitates the method and reduces the expenses and risks related to blood processing.

Familial aggregation of arterial blood pressure and possible genetic influence

The aggregation of arterial blood pressure, weight, and height were compared between family members of children and adolescents with blood pressure percentiles at or above 95 (group 1) and at or below 50 (group 2). Weight, height, and systolic and diastolic blood pressures were significantly higher in siblings and target individuals of group 1 (p less than 0.001). Weight and systolic and diastolic blood pressures were significantly higher in mothers of group 1 (p less than 0.001). Covariant analysis comparing the average systolic and diastolic blood pressures of both groups controlled by age, age and weight, and age and Quetelet index revealed that the arterial blood pressure of mothers, siblings, and target individuals remained higher in group 1 (p less than 0.05 to p less than 0.001). These observations show a strong familial aggregation of arterial blood pressure not dependent only on physical development and also raise the question of a genetic basis as a possible mechanism of systemic arterial hypertension.

The significance of physical development on the blood pressure curve of children between 6 and 9 years of age and its relationship with familial aggregation

Arterial blood pressure values of 3109 children between 6 and 9 years of age in the city of Rio de Janeiro were analysed according to low, medium and high socio-economic levels. At medium and high socio-economic levels, arterial pressures, weight and height were higher than those observed in children of a lower socio-economic level. Blood pressure was best correlated to body weight. The aggregation of arterial pressure, weight and height was compared between family members of children with percentiles below 50 and above 90. Systolic blood pressure and weight were significantly lower in family members with a percentile below 50. We conclude that there is a need for a long-term follow-up of these children and their families, in order to improve our knowledge of the mechanisms involved in the origin of arterial hypertension.

[Epidemiology of human leptospirosis, with special reference to greater Rio de Janeiro, Brazil, from 1970 to 1982]

From 1970 to 1982, 884 cases of human leptospirosis were serologically diagnosed at the Leptospirosis Laboratory, Fundação Oswaldo Cruz - FIOCRUZ, by means of the microscopic agglutination test. Of these patients, 775 were hospitalized in the city of Rio de Janeiro, and 109 were reported by other Brazilian cities. Icterohaemorrhagiae was the presumptive infecting serogroup most commonly encountered in greater Rio patients (76.4%) and in the others (41.3%). During this 13-year period, two Icterohaemorrhagiae strains were isolated. In greater Rio the illness predominated between January and April (53.7%), the male sex accounted for 89.9% of the cases, and patients ranging from 16 to 45 year-olds were the most affected (74.9%).