Effects of environmental modification on mastitis occurrence and hormonal changes in Holstein cows

The purpose of this research was to evaluate the effects of evaporative cooling in freestall on mastitis occurrence, milk production, and composition, as well as cortisol, T3 (triiodothyronine), and T4 (thyroxin) levels in lactating dairy cows. Twenty-eight multiparous cows averaging 70 ± 10 day postpartum were used in four treatments from January to March 2003. The treatments were: Day (cooling from 7:00 a.m. to 7:00 p.m.); Night (cooling from 7:00 p.m. to 7:00 a.m.); 24-hour (cooling 24-hour); and Control (no cooling). Wired cup test was used for clinical mastitis diagnosis, and the California Mastitis Test (CMT) was used to identify subclinical mastitis. Blood and milk samples were taken weekly for microbiological and hormonal analyses. The cortisol levels were higher than normal values in all treatment groups, suggesting stress conditions, but T3 and T4 levels remained normal in all groups. The occurrence of subclinical mastitis was lower in Day and Night groups than in Control and 24-hour groups. Regarding the microbiological analyses, in all groups the isolation of Corynebacterium sp. from milk samples increased while negative coagulase staphylococci (CNS) declined as etiological agents of subclinical mastitis. However, in Day and 24-hour groups, coagulase positive staphylococci (CPS) increased mainly Staphylococcus aureus (49.8% and 47.7% respectively). The Night group showed a decrease in subclinical mastitis occurrences. Our data indicate that all animals subjected to treatments presented high levels of cortisol, indicating a stress condition. The Night treatment presented a reduction in microbial isolation, suggesting a reduced susceptibility to mastitis.

Thyroid function in post-weaning rats whose dams were fed a low-protein diet during suckling

This study was designed to evaluate the thyroid and pituitary hormone levels in post-weaning rats whose dams were fed a low-protein diet during suckling (21 days). The dams and pups were divided into 2 groups: a control group fed a diet containing 22% protein that supplies the necessary amount of protein for the rat and is the usual content of protein in most commercial rat chow, and a diet group fed a low-protein (8%) diet in which the protein was substituted by an isocaloric amount of starch. After weaning all dams and pups received the 22% protein diet. Two hours before sacrifice of pups aged 21, 30 and 60 days, a tracer dose (0.6 µCi) of 125I was injected (ip) into each animal. Blood and thyroid glands of pups were collected for the determination of serum T4, T3 and TSH and radioiodine uptake. Low protein diet caused a slight decrease in radioiodine uptake at 21 days, and a significant decrease in T3 levels (128 ± 14 vs 74 ± 9 ng/dl, P<0.05), while T4 levels did not change and TSH was increased slightly. At 30 days, T3 and TSH did not change while there was a significant increase in both T4 levels (4.8 ± 0.3 vs 6.1 ± 0.2 µg/dl, P<0.05) and in radioiodine uptake levels (0.34 ± 0.02 vs 0.50 ± 0.03%/mg thyroid, P<0.05). At 60 days serum T3, T4 and TSH levels were normal, but radioiodine uptake was still significantly increased (0.33 ± 0.02 vs 0.41 ± 0.03%/mg thyroid, P<0.05). Thus, it seems that protein malnutrition of the dams during suckling causes hypothyroidism in the pups at 21 days that has a compensatory mechanism increasing thyroid function after refeeding with a 22% protein diet. The radioiodine uptake still remained altered at 60 days, when all the hormonal serum levels returned to the normal values, suggesting a permanent change in the thyroid function

Increased angiotensin-converting enzyme activity in the left ventricle after infarction

An increase in angiotensin-converting enzyme (ACE) activity has been observed in the heart after myocardial infarction (MI). Since most studies have been conducted in chronically infarcted individuals exhibiting variable degrees of heart failure, the present study was designed to determine ACE activity in an earlier phase of MI, before heart failure development. MI was produced in 3-month old male Wistar rats by ligation of the anterior branches of the left coronary artery, control rats underwent sham surgery and the animals were studied 7 or 15 days later. Hemodynamic data obtained for the anesthetized animals showed normal values of arterial blood pressure and of end-diastolic pressure in the right and left ventricular cavities of MI rats. Right and left ventricular (RV, LV) muscle and scar tissue homogenates were prepared to determine ACE activity in vitro by measuring the velocity of His-Leu release from the synthetic substrate Hyp-His-Leu. ACE activity was corrected to the tissue wet weight and is reported as nmol His-Leu g-1 min-1. No significant change in ACE activity in the RV homogenates was demonstrable. A small nonsignificant increase of ACE activity (11 &plusmn; 9%; P0.05) was observed 7 days after MI in the surviving left ventricular muscle. Two weeks after surgery, however, ACE activity was 46 &plusmn; 11% (P<0.05) higher in infarcted rats compared to sham-operated rats. The highest ACE activity was demonstrable in the scar tissue homogenate. In rats studied two weeks after surgery, ACE activity in the LV muscle increased from 105 &plusmn; 7 nmol His-Leu g-1 min-1 in control hearts to 153 &plusmn; 11 nmol His-Leu g-1 min-1 (P<0.05) in the remaining LV muscle of MI rats and to 1051 &plusmn; 208 nmol His-Leu g-1 min-1 (P<0.001) in the fibrous scar. These data indicate that ACE activity increased in the heart after infarction before heart failure was demonstrable by hemodynamic measurements. Since the blood vessels of the scar drain to the remaining LV myocardium, the high ACE activity present in the fibrous scar may increase the angiotensin II concentration and decrease bradykinin in the cardiac tissues surrounding the infarcted area. The increased angiotensin II in the fibrous scar may contribute to the reactive fibrosis and hypertrophy in the left ventricular muscle surviving infarction

Differences between remaining ability and loss of capacity in maximum aerobic impairment

In the evaluation of exercise intolerance of patients with respiratory diseases the American Medical Association (AMA) and the American Thoracic Society (ATS) have proposed similar classifications for rating aerobic impairment using maximum oxygen uptake (VO2max) normalized for total body weight (ml min-1 kg-1). However, subjects with the same VO2max weight-corrected values may have considerably different losses of aerobic performance (VO2max expressed as % predicted). We have proposed a new, specific method for rating loss of aerobic capacity (VO2max, % predicted) and we have compared the two classifications in a prospective study involving 75 silicotic claimants. Logistic regression analysis showed that the disagreement between rating systems (higher dysfunction by the AMA/ATS classification) was associated with age >50 years (P<0.005) and overweight (P = 0.04). Interestingly, clinical (dyspnea score) and spirometric (FEV1) normality were only associated with the VO2max, % predicted, normal values (P<0.01); therefore, in older and obese subjects the AMA/ATS classification tended to overestimate the aerobic dysfunction. We conclude that in the evaluation of aerobic impairment in patients with respiratory diseases, the loss of aerobic capacity (VO2max, % predicted) should be used instead of the traditional method (remaining aerobic ability, VO2max, in ml min-1 kg-1).

Biochemical profile of amniotic fluid for the assessment of fetal and renal development

Creatinine plays a key role in the function and maturation of fetal kidneys throughout pregnancy. It is important to identify other markers that may help in the diagnosis of renal dysfunction. Our aim was to determine the profile of and the correlation between biochemical markers to be used to assess renal function and maturation of the fetus in the amniotic fluid during pregnancy and to determine the distribution of normal values for creatinine, N-acetyl-ß-D-glucosaminidase (NAG), ß2-microglobulin, glucose, urea, sodium, potassium, phosphorus, calcium, uric acid, albumin, and osmolality in three gestational age groups. This was a cross-section study that assessed 115 samples of amniotic fluid during three different periods of pregnancy, i.e., 13 to 20, 27 to 34, and 36 to 42 weeks. Concentrations of creatinine, NAG, urea, potassium and uric acid increased during pregnancy (P<0.05). ß2-Microglobulin, glucose, sodium, phosphorus, calcium, and albumin concentration and osmolality decreased (P<0.05), whereas ß2-microglobulin, glucose and uric acid presented significant correlations with gestational age and creatinine, respectively (r>0.6, P<0.05). Urea, potassium and phosphorus showed mild correlations with both (r>0.5, P<0.05). NAG, sodium, albumin and osmolality did not show significant correlations (r<0.5, P<0.05). These tests confirmed the important role of creatinine in terms of correlation with gestational age. ß2-Microglobulin, glucose and uric acid were significant as markers of function and maturation of fetal kidneys, whereas NAG did not demonstrate a useful role for the assessment of renal maturation.

Lack of evidence for the pathogenic role of iron and HFE gene mutations in Brazilian patients with nonalcoholic steatohepatitis

The hypothesis of the role of iron overload associated with HFE gene mutations in the pathogenesis of nonalcoholic steatohepatitis (NASH) has been raised in recent years. In the present study, biochemical and histopathological evidence of iron overload and HFE mutations was investigated in NASH patients. Thirty-two NASH patients, 19 females (59%), average 49.2 years, 72% Caucasians, 12% Mulattoes and 12% Asians, were submitted to serum aminotransferase and iron profile determinations. Liver biopsies were analyzed for necroinflammatory activity, architectural damage and iron deposition. In 31 of the patients, C282Y and H63D mutations were tested by PCR-RFLP. Alanine aminotransferase levels were increased in 30 patients, 2.42 ± 1.12 times the upper normal limit on average. Serum iron concentration, transferrin saturation and ferritin averages were 99.4 ± 31.3 g/dl, 33.1 ± 12.7% and 219.8 ± 163.8 µg/dl, respectively, corresponding to normal values in 93.5, 68.7 and 78.1% of the patients. Hepatic siderosis was observed in three patients and was not associated with architectural damage (P = 0.53) or with necroinflammatory activity (P = 0.27). The allelic frequencies (N = 31) found were 1.6 and 14.1% for C282Y and H63D, respectively, which were compatible with those described for the local population. In conclusion, no evidence of an association of hepatic iron overload and HFE mutations with NASH was found. Brazilian NASH patients comprise a heterogeneous group with many associated conditions such as hyperinsulinism, environmental hepatotoxin exposure and drugs, but not hepatic iron overload, and their disease susceptibility could be related to genetic and environmental features other than HFE mutations.

A routine electrocardiogram cannot be used to determine the size of myocardial infarction in the rat

Nine lead electrocardiograms of non-infarcted (N = 61) and infarcted (N = 71) female Wistar rats (200-250 g) were analyzed in order to distinguish left ventricle myocardial infarction (MI) larger than 40% (LMI) from MI smaller than 40% (SMI). MI larger than 40% clearly caused a deviation of ÂQRS and ÂT from normal values of 270-360 degrees to 90-270 degrees. Infarcted rats showed Q wave in D1 larger than 1 mm with 94% sensitivity and 100% specificity. The sum of QRS positivity in V1, V2 and V6 lower than 10 mm identified MI with 82% sensitivity and 100% specificity. The data showed that MI can be easily and reliably diagnosed by electrocardiogram in the rat. However, contradicting what is frequently believed, when specificity and sensitivity were analyzed focusing on MI size, none of these current electrocardiographic indices of MI size adequately discriminates LMI from SMI.

Evaluation of hemostatic changes using thromboelastography after crystalloid or colloid fluid administration during major orthopedic surgery

The effects of Ringer lactate, 6% hydroxyethyl starch (HES) (130/0.4) or 4% succinylated gelatin solutions on perioperative coagulability were measured by thromboelastography (TEG). Seventy-five patients (ASA I-III) who were to undergo major orthopedic procedures performed under epidural anesthesia were included in the study. Patients were randomly divided into three groups of 25 each for the administration of maintenance fluids: group RL (Ringer lactate), group HES (6% HES 130/0.4), and group JEL (4% gelofusine solution). Blood samples were obtained during the perioperative period before epidural anesthesia (t1, baseline), at the end of the surgery (t2), and 24 h after the operation (t3). TEG data, reaction time (R), coagulation time (K), angle value (α), and maximum amplitude (MA) were recorded. TEG parameters changed from normal values in all patients. In group RL, R and K times decreased compared to perioperative values while the α angle and MA increased (P < 0.05). In group HES, R and K times increased, however, the α angle and MA decreased (P < 0.05). In group JEL, R time increased (P < 0.05), but K time, α angle and MA did not change significantly. In the present study, RL, 6% HES (130/0.4) and 4% JEL solutions caused changes in the coagulation system of all patients as measured by TEG, but these changes remained within normal limits.

Transtracheal puncture: a forgotten procedure

Transtracheal puncture has long been known as a safe, low-cost procedure. However, with the advent of bronchoscopy, it has largely been forgotten. Two researchers have suggested the use of α-amylase activity to diagnose salivary aspiration, but the normal values of this enzyme in tracheobronchial secretions are unknown. We aimed to define the normal values of α-amylase activity in tracheobronchial secretions and verify the rate of major complications of transtracheal puncture. From October 2009 to June 2011, we prospectively evaluated 118 patients without clinical or radiological signs of salivary aspiration who underwent transtracheal puncture before bronchoscopy. The patients were sedated with a solution of lidocaine and diazepam until they reached a Ramsay sedation score of 2 or 3. We then cleaned the cervical region and anesthetized the superficial planes with lidocaine. Next, we injected 10 mL of 2% lidocaine into the tracheobronchial tree. Finally, we injected 10 mL of normal saline into the tracheobronchial tree and immediately aspirated the saline with maximum vacuum pressure to collect samples for measurement of the α-amylase level. The α-amylase level mean ± SE, median, and range were 1914 ± 240, 1056, and 24-10,000 IU/L, respectively. No major complications (peripheral desaturation, subcutaneous emphysema, cardiac arrhythmia, or hemoptysis) occurred among 118 patients who underwent this procedure. Transtracheal aspiration is a safe, low-cost procedure. We herein define for the first time the normal α-amylase levels in the tracheobronchial secretions of humans.

Detection of incipient left ventricular hypertrophy in mild to moderate arterial hypertension with normal electrocardiogram and echocardiogram: a new use for signal-averaged electrocardiography

OBJECTIVE: To assess signal-averaged electrocardiogram (SAECG) for diagnosing incipient left ventricular hypertrophy (LVH). METHODS: A study with 115 individuals was carried out. The individuals were divided as follows: GI - 38 healthy individuals; GII - 47 individuals with mild to moderate hypertension and normal findings on echocardiogram and ECG; and GIII - 30 individuals with hypertension and documented LVH. The magnitude vector of the SAECG was analyzed with the high-pass cutoff frequency of 40 Hz through the bidirectional four-pole Butterworth high-pass digital filter. The mean quadratic root of the total QRS voltage (RMST) and the two-dimensional integral of the QRS area of the spectro-temporal map were analyzed between 0 and 30 Hz for the frequency domain (Int FD), and between 40 and 250 Hz for the time domain (Int TD). The electrocardiographic criterion for LVH was based on the Cornell Product. Left ventricular mass was calculated with the Devereux formula. RESULTS: All parameters analyzed increased from GI to GIII, except for Int FD (GII vs GIII) and RMST log (GII vs GIII). Int TD showed greater accuracy for detecting LVH with an appropriate cutoff > 8 (sensitivity of 55%, specificity of 81%). Positive values (> 8) were found in 56.5% of the G II patients and in 18.4% of the GI patients (p< 0.0005). CONCLUSION: SAECG can be used in the early diagnosis of LVH in hypertensive patients with normal ECG and echocardiogram.

Lipoides do plasma normal

1. In a series of 21 normal cases we found for fatty acids per 100 cc. of plasma an average of 332 mgm., being 314 mgm. for the male sex and 350 mgm. for the female sex. 2.- For lecithin, in four normal cases we found per 100 cc. of plasma 182 mgm. estimated by the contents is phosphorus which ranged from 6.12 to 9.0 mgrs. 3.- Cholesterol in 20 normal cases showed 172 mgm. per 100 cc. of plasma. The averages were 151 mgm. for men and 194 mgm. for women. 4.- The readings of the fractions were 2.01 for the ratio fatty acids divided by lecithins 0.90 for lecithin divided by cholesterol and 1.93 for fatty acids divided by cholesterol. 5.- On comparing the results obtained by us with those reported in foreign literature an absolute conformity is noted chiefly with the values supplied by Bloor and Horiuchi for the ratios among the various lipoid fractions. The average for Cholesterol is comparable with that obtained by Myers but is slightly under that of Bloor's. The lecithin contents found by us did not reach such high values as those supplied by foreign authors.

Comparison of standardized uptake values measured on 18F-NaF PET/CT scans using three different tube current intensities

Objective: To analyze standardized uptake values (SUVs) using three different tube current intensities for attenuation correction on 18FNaF PET/CT scans. Materials and Methods: A total of 254 18F-NaF PET/CT studies were analyzed using 10, 20 and 30 mAs. The SUVs were calculated in volumes of interest (VOIs) drawn on three skeletal regions, namely, right proximal humeral diaphysis (RH), right proximal femoral diaphysis (RF), and first lumbar vertebra (LV1) in a total of 712 VOIs. The analyses covered 675 regions classified as normal (236 RH, 232 RF, and 207 LV1). Results: Mean SUV for each skeletal region was 3.8, 5.4 and 14.4 for RH, RF, and LV1, respectively. As the studies were grouped according to mAs value, the mean SUV values were 3.8, 3.9 and 3.7 for 10, 20 and 30 mAs, respectively, in the RH region; 5.4, 5.5 and 5.4 for 10, 20 and 30 mAs, respectively, in the RF region; 13.8, 14.9 and 14.5 for 10, 20 and 30 mAs, respectively, in the LV1 region. Conclusion: The three tube current values yielded similar results for SUV calculation.

The normal electrocardiogram in the clinically healthy Saanen goats

The purpose of this study was to establish normal reference electrocardiographic (ECG) values for standard limb lead II in Saanen goats. For this, were used 19 healthy adult female Saanen goats. And for reference values for the ECG parameters, were used 95% confidence level. The overall P, Q, R, S and T durations (seconds) were 0.03±0.01, 0.02±0.005, 0.03±0.014, 0.03±0.011, 0.06±0.014 respectively, and the reference values were 0.01-0.04, 0.01-0.02, 0.01-0.06, 0.02-0.04 and 0.04-0.08 respectively. The amplitudes (milivolts) of these waveforms were 0.1±0.031, 0.06±0.023, 0.44±0.312, 0.39±0.434, 0.26±0.164 (T negative) and 0.15±0.071 (T positive), respectively. The reference values were 0.05-0.15, 0.05-0.1, 0.05-1.2, 0.05-1.1 and -0.2-0.7 respectively. The PR and QT interval, the QRS complex and the ST segment durations (seconds) were 0.08±0.018, 0.26±0.03, 0.05±0.008, 0.15±0.041 respectively. The reference values were 0.06-0.12, 0.2-0.32, 0.04-0.07 and 0.11-0.26, respectively. It was possible to observe differences in ECG of Saanen goats regarding the amplitude and duration of the constituents when compared to the results of other breeds. Therefore it is necessary to conduct further studies to allow comparisons, detect and diagnose cardiac arrhythmias and help the development of therapies.

Specific insulin and proinsulin in normal glucose tolerant first-degree relatives of NIDDM patients

In order to identify early abnormalities in non-insulin-dependent diabetes mellitus (NIDDM) we determined insulin (using an assay that does not cross-react with proinsulin) and proinsulin concentrations. The proinsulin/insulin ratio was used as an indicator of abnormal ß-cell function. The ratio of the first 30-min increase in insulin to glucose concentrations following the oral glucose tolerance test (OGTT; I30-0/G30-0) was taken as an indicator of insulin secretion. Insulin resistance (R) was evaluated by the homeostasis model assessment (HOMA) method. True insulin and proinsulin were measured during a 75-g OGTT in 35 individuals: 20 with normal glucose tolerance (NGT) and without diabetes among their first-degree relatives (FDR) served as controls, and 15 with NGT who were FDR of patients with NIDDM. The FDR group presented higher insulin (414 pmol/l vs 195 pmol/l; P = 0.04) and proinsulin levels (19.6 pmol/l vs 12.3 pmol/l; P = 0.03) post-glucose load than the control group. When these groups were stratified according to BMI, the obese FDR (N = 8) showed higher fasting and post-glucose insulin levels than the obese NGT (N = 9) (fasting: 64.8 pmol/l vs 7.8 pmol/l; P = 0.04, and 60 min post-glucose: 480.6 pmol/l vs 192 pmol/l; P = 0.01). Also, values for HOMA (R) were higher in the obese FDR compared to obese NGT (2.53 vs 0.30; P = 0.075). These results show that FDR of NIDDM patients have true hyperinsulinemia (which is not a consequence of cross-reactivity with proinsulin) and hyperproinsulinemia and no dysfunction of a qualitative nature in ß-cells.

Diagnosing dementia and normal aging: clinical relevance of brain ratios and cognitive performance in a Brazilian sample

The main objective of the present study was to evaluate the diagnostic value (clinical application) of brain measures and cognitive function. Alzheimer and multiinfarct patients (N = 30) and normal subjects over the age of 50 (N = 40) were submitted to a medical, neurological and cognitive investigation. The cognitive tests applied were Mini-Mental, word span, digit span, logical memory, spatial recognition span, Boston naming test, praxis, and calculation tests. The brain ratios calculated were the ventricle-brain, bifrontal, bicaudate, third ventricle, and suprasellar cistern measures. These data were obtained from a brain computer tomography scan, and the cutoff values from receiver operating characteristic curves. We analyzed the diagnostic parameters provided by these ratios and compared them to those obtained by cognitive evaluation. The sensitivity and specificity of cognitive tests were higher than brain measures, although dementia patients presented higher ratios, showing poorer cognitive performances than normal individuals. Normal controls over the age of 70 presented higher measures than younger groups, but similar cognitive performance. We found diffuse losses of tissue from the central nervous system related to distribution of cerebrospinal fluid in dementia patients. The likelihood of case identification by functional impairment was higher than when changes of the structure of the central nervous system were used. Cognitive evaluation still seems to be the best method to screen individuals from the community, especially for developing countries, where the cost of brain imaging precludes its use for screening and initial assessment of dementia.