Fertility in seasonal-calving pasture-based lactating dairy cows following timed artificial insemination or timed embryo transfer with fresh or frozen in vitro-produced embryos.

The objective was to compare pregnancy per service event (P/S) in lactating dairy cows following timed artificial insemination (AI) or timed embryo transfer (ET) using either fresh or frozen in vitro-produced embryos. Oocytes were collected once per week for up to 9 wk using transvaginal ovum pick-up from elite dairy donors (ET-DAIRY; n = 40; Holstein-Friesian and Jersey) and elite beef donors (ET-ELITE-BEEF; n = 21; Angus). Both ET-DAIRY and ET-ELITE-BEEF donors consisted of heifers and cows. In addition, oocytes were collected from the ovaries of beef heifers of known pedigree following slaughter at a commercial abattoir (ET-COMM-BEEF; n = 119). Following in vitro maturation and fertilization, presumptive zygotes were cultured in vitro to the blastocyst stage. Grade 1 blastocysts were either transferred fresh or frozen for on-farm thawing and direct transfer. A total of 1,106 recipient cows (all lactating, predominantly Holstein-Friesian) located on 16 herdlets were blocked based on parity, calving date, and Economic Breeding Index, and randomly assigned to receive AI (n = 243) or ET (n = 863) after estrous synchronization with a 10-d Progesterone-synch protocol. Cows assigned to ET were further randomized to receive fresh (n = 187) or frozen (n = 178) ET-ELITE-BEEF embryos, fresh (n = 169) or frozen (n = 162) ET-DAIRY embryos, or fresh (n = 80) or frozen (n = 87) ET-COMM-BEEF embryos. Pregnancy was diagnosed using transrectal ultrasound on d 32 to 35 after synchronized ovulation and confirmed on d 62 to 65, at which time fetal sex was determined. Pregnancy per service event at d 32 was not different between AI (48.8%) and ET (48.9%) and did not differ between dairy and beef embryos (50.3% vs. 48.1%, respectively). However, P/S was less on d 32 following transfer of frozen embryos (41.6%) compared with fresh embryos (56.1%). Pregnancy loss between d 32 and 62 was greater for ET (15.1%) compared with AI (4.7%), with greater losses observed for frozen beef (18.5%), fresh beef (17.3%), and frozen dairy (19.2%) compared with fresh dairy (6.0%) embryos. Serum progesterone (P4) concentration on d 7 was associated with P/S at d 32 and 62. Cows in the quartile with the least serum P4 concentrations (quartile 1) had less probability of being pregnant on d 32 (33.4%) compared with cows in the 3 upper quartiles for serum P4 (45.7%, 55.6%, and 61.2% for quartile 2, quartile 3, and quartile 4, respectively). Sex ratio (male:female) at d 62 was skewed toward more male fetuses following ET (61.1:38.9) compared with AI (43.2:56.8) and was consistent with the sex ratio among in vitro blastocysts (61.2:38.8). In conclusion, P/S was similar for AI and ET, although pregnancy loss between d 32 and 62 was greater for ET than for AI.

Using rumination and activity data for early detection of anaplasmosis disease in dairy heifer calves.

Bovine anaplasmosis causes considerable economic losses in dairy cattle production systems worldwide, ranging from $300 million to $900 million annually. It is commonly detected through rectal temperature, blood smear microscopy, and packed cell volume (PCV). Such methodologies are laborious, costly, and difficult to systematically implement in large-scale operations. The objectives of this study were to evaluate (1) rumination and activity data collected by Hr-Tag sensors (SCR Engineers Ltd.) in heifer calves exposed to anaplasmosis; and (2) the predictive ability of recurrent neural networks in early identification of anaplasmosis. Additionally, we aimed to investigate the effect of time series length before disease diagnosis (5, 7, 10, or 12 consecutive days) on the predictive performance of recurrent neural networks, and how early anaplasmosis disease can be detected in dairy calves (5, 3, and 1 d in advance). Twenty-three heifer calves aged 119 ± 15 (mean ± SD) d and weighing 148 ± 20 kg of body weight were challenged with 2 × 107 erythrocytes infected with UFMG1 strain (GenBank no. EU676176) isolated from Anaplasma marginale. After inoculation, animals were monitored daily by assessing PCV. The lowest PCV value (14 ± 1.8%) and the finding of rickettsia on blood smears were used as a criterion to classify an animal as sick (d 0). Rumination and activity data were collected continuously and automatically at 2-h intervals, using SCR Heatime Hr-Tag collars. Two time series were built including last sequence of -5, -7, -10, or -12 d preceding d 0 or a sequence of 5, 7, 10, or 12 d randomly selected in a window from -50 to -15 d before d 0 to ensure a sequence of days in which PCV was considered normal (32 ± 2.4%). Long short-term memory was used as a predictive approach, and a leave-one-animal-out cross-validation (LOAOCV) was used to assess prediction quality. Anaplasmosis disease reduced 34 and 11% of rumination and activity, respectively. The accuracy, sensitivity, and specificity of long short-term memory in detecting anaplasmosis ranged from 87 to 98%, 83 to 100%, and 83 to 100%, respectively, using rumination data. For activity data, the accuracy, sensitivity, and specificity varied from 70 to 98%, 61 to 100%, and 74 to 100%, respectively. Predictive performance did not improve when combining rumination and activity. The use of longer time-series did not improve the performance of models to predict anaplasmosis. The accuracy and sensitivity in predicting anaplasmosis up to 3 d before clinical diagnosis (d 0) were greater than 80%, confirming the possibility for early identification of anaplasmosis disease. These findings indicate the great potential of wearable sensors in early identification of anaplasmosis diseases. This could positively affect the profitability of dairy farmers and animal welfare.

Plasma progesterone concentration after first service is associated with individual genetic traits, postpartum phenotypes, and likelihood of conception in seasonal-calving pasture-based dairy cows.

The aims of this study were to (1) evaluate postpartum phenotypes, cow factors, and genetic traits associated with plasma progesterone (P4) concentrations after first artificial insemination (AI); (2) determine variation in daily plasma P4 concentrations between d 7 and 13 after first AI; and (3) evaluate associations between plasma P4 concentrations and pregnancy success after first AI. First and second parity (n = 2,797) spring-calving lactating dairy cows from 35 dairy herds were enrolled. Farm visits were performed every 2 wk during the postpartum period as follows: cows that were at wk 3 (range: 14-27 d in milk) and wk 7 (range: 42-55 d in milk) postpartum were examined. Farm visits were performed weekly during the breeding season, and cows that were between 7 and 13 d after the first AI were examined. Body condition score (BCS) was measured at each visit using a 1 to 5 scale [low (≤2.75), target (≥3.0)]. Transrectal ultrasound examinations were conducted at wk 3 and wk 7 postpartum visits to determine presence or absence of a corpus luteum (CL) and uterine tract score [scale of G1 (best)-G4 (worst)]. Blood samples were collected at each visit, and plasma concentrations of glucose, ß-hydroxybutyrate, and fatty acids were analyzed. On the day of the weekly farm visit during the breeding season, blood samples for P4 determination were collected from all cows that were between 7 and 13 d after first AI during the breeding period. Cows that had a CL present and a G1 uterine score at wk 7 postpartum had greater plasma P4 concentration after first AI (+0.67 ng/mL and +0.4 ng/mL, respectively) compared with cows with no CL present and with a uterine score ≥G3. Cows with low BCS at wk 7 postpartum had lesser plasma P4 concentration after first AI than cows with target BCS. Each unit increase in plasma fatty acids and ß-hydroxybutyrate concentration at AI was associated with 0.45 ± 0.33 ng/mL (estimate ± standard error) and 0.07 ± 0.04 ng/mL greater plasma P4 concentration after first AI, respectively. Regarding genetic merit traits, each unit increase in fertility subindex was associated with 0.005 ± 0.003 ng/mL greater P4 concentration. In addition, for every 1 ng/mL increase in plasma P4 concentration, the odds of estimated probability of pregnancy per AI increased by 3% (odds ratio = 1.03; 95% confidence interval = 1.00, 1.05). In conclusion, cows with superior genetic merit for fertility traits and milk production traits, favorable fertility phenotypes at wk 7 postpartum, (e.g., presence of a CL, a G1 uterine score, and target BCS), and blood parameters indicative of better metabolic status at AI were all associated with greater plasma P4 concentration after AI. In turn, greater plasma P4 concentrations were associated with greater odds of successful pregnancy establishment. This study underlines the important associations between early postpartum fertility phenotypes (CL presence, uterine health status) and subsequent plasma P4 concentrations after first AI, and hence provides additional evidence of the mechanisms through which selection for fertility traits improves phenotypic fertility performance.

Expression of immune response genes in peripheral blood of cattle infested with Rhipicephalus microplus.

The bovine tick Rhipicephalus microplus is responsible for severe economic losses in tropical cattle production. Bos indicus breeds are more resistant to tick infestations than are Bos taurus breeds, and the understanding of the physiological mechanisms involved in this difference is important for the development of new methods of parasite control. We evaluated differences in the transcript expression of genes related to the immune response in the peripheral blood of cattle previously characterized as resistant or susceptible to tick infestation. Crossbreed F2 Gir x Holstein animals (resistant, N = 6; susceptible, N = 6) were artificially submitted to tick infestation. Blood samples were collected at 0, 24, and 48 h after tick infestation and evaluated for transcript expression of the CD25, CXCL8, CXCL10, FoxP3, interleukin (IL)-10, and tumor necrosis factor alpha (TNFα) genes. Gene expression of CD25 (6.00, P < 0.01), IL-10 (31.62, P < 0.01), FoxP3 (35.48, P < 0.01), and CXCL10 (3.38, P < 0.05) was altered in the resistant group at 48 h compared with samples collected before infestation. In the susceptible group, CXCL8 (-2.02, P < 0.05) and CXCL10 (2.20, P < 0.05) showed altered expression 24 h after infestation. CXCL8 (-5.78, P < 0.05) also showed altered expression at 48 h after infestation when compared with samples collected before infestation. We detected a correlation between T γδ cell activity and the immunological mechanisms that result in a higher resistance to R. microplus in cattle.

Efficiency of sulphur in garlic extract and non-sulphur homeopathy in the control of the cattle tick Rhipicephalus (Boophilus) microplus.

The objective of the present work was to evaluate the efficacy of a non-sulphur-based homeopathic preparation and a sulphur-containing natural product derived from Allium sativum (Linnaeus) against infestation by the cattle tick Rhipicephalus (Boophilus) microplus (Canestrini) (Acari: Ixodidae). A total of 24 crossbred calves (7 : 8 Holstein : Zebu), aged 6-8 months and maintained in individual stables under tick-free conditions, were divided into three groups. Group 1 (control group) received no treatment; Group 2 was treated with 0.01 g/day of the homeopathic preparation Fator C&MC(®), and Group 3 was treated with 20 g/day of Enxofre-Allium sativum(®). After adaptation to the diet for 1 month, each calf was subjected to artificial infestation with 8000 R. (B.) microplus larvae (aged 7-14 days) twice per week over a 5-month period. Numbers of engorged females were recorded every 14 days and samples of freely released engorged females were collected at 14-day intervals commencing 3 months after the start of the experiment. The engorged females were weighed, incubated for 15 days under biochemical oxygen demand conditions at 27 ± 1 °C and relative humidity >85%, and the weights of the egg masses produced were recorded. Other biological parameters, including reproduction estimate, reduction in oviposition and efficiency of treatment, were determined. A significant reduction in the number of engorged females was detected on animals treated with Enxofre-Allium sativum(®) (Group 3) in comparison with the other two groups. The overall efficiency of the treatment with the sulphur-containing product was 64%, whereas that of the homeopathic preparation was 26%. Under the experimental conditions established, Enxofre-Allium sativum(®) can reduce the intensity of the R. (B.) microplus infestation.

Expressed sequenced tags profiling of resistant and susceptible Gyr x Holstein cattle infested with the tick Rhipicephalus (Boophilus) microplus.

Tick resistance in cattle is mainly found in zebu (Bos indicus) animals, although it is also present in some taurine (B. taurus) breeds. In order to characterize functional genes involved in tick resistance/susceptibility in cattle, two cDNA libraries were generated using skin tissues of selected Holstein x Gyr animals. A total of 2700 high-quality reads from both resistant and susceptible cDNA were assembled into 458 sequences (contigs) and 834 singletons, with a mean size of 447.7 nucleotides. Assignment of homologous proteins by BLASTX revealed 790 (61.1%) and 300 (23.2%) hits in resistant and susceptible cDNA, respectively; 121 of these hits matched bovine proteins. A total of 502 (38.9%) unique sequences were found to have no significant homology with known sequences and were classified as novel sequences. In general, the most abundant sequences consisted of those coding for hypothetical proteins whose function had not yet been determined, in addition to ribosomal proteins, binding proteins and structural proteins, such as keratin and collagen. The most abundant protein found was collagen type III alpha, although ribosomal proteins accounted for half of the 40 most frequent hits. In addition, five matches within the top 40 best hits corresponded to immune response proteins. These sequences could be used for future studies on functional genomics of cattle tick resistance as well as for genomic sequencing projects.

Cow-level prevalence and risk factors for estrus detection inaccuracy in seasonal calving pasture-based dairy cows.

High submission rates and pregnancies per AI are essential to ensure compact calving is achieved in seasonal calving pasture-based systems. Estrus detection inaccuracy (EDI) is one area that negatively impacts pregnancies per AI as it increases the inseminations per pregnancy with little probability of conception, while also having the potential to disrupt established pregnancies. The aims of this cross-sectional study were to provide cow-level estimates of EDI prevalence and determine cow-level risk factors for EDI in seasonal calving pasture-based systems. A total of 1071 milk samples were obtained from 984 cows on 19 farms in spring 2018 and analyzed by radioimmunoassay to determine the progesterone concentration at the time of artificial insemination. Based on a validation study on a subset of cows, an inaccurate estrus detection was described as a concentration of progesterone in foremilk of ≥3 ng/ml which corresponded to a composite milk progesterone value of 5 ng/ml. To investigate selected risk factors for EDI, we conducted statistical analyses using two multivariate logistic regression models, stratifying by insemination number (first versus repeat). The overall prevalence of EDI was 4.7% with a prevalence of 3.3% of EDI at first insemination and 14.1% at repeat insemination. Absence of a mounting abrasion (Adjusted odds ratio (AOR) = 3.0) was a significant risk factor for EDI on first insemination while abnormal preceding repeat interval (AOR = 9.5), the absence of an observed standing estrus (AOR = 12.5) and the absence of a mounting abrasion (AOR = 4.1) were significant risk factors for EDI on repeat insemination. The results indicate that cow-level estimated prevalence of EDI in a selection of pasture-based herds was low at first insemination but higher for repeat insemination. It confirms that certain cow-level risk factors existed for EDI, thus providing preliminary evidence for potential future investigation into the targeted use of on-farm progesterone assays in pasture-based herds.

Differential expression of genes in resistant versus susceptible Gyr x Holstein cattle challenged with the tick Rhipicephalus (Boophilus) microplus.

The bovine tick Rhipicephalus (Boophilus) microplus causes major losses in cattle production systems in tropical regions. Bos indicus breeds are more resistant to ticks than B. taurus breeds. Resistance genes could be an alternative to control this parasite. We examined the pattern of gene expression of three calcium-binding-protein genes: translationally controlled tumor protein 1 (TPT1), allergen Bos d3 (S100A7), calcium channel protein transient receptor potential vanilloid 6 (TRPV6), and the cysteine proteinase inhibitor gene (CST6). These genes were selected from cDNA libraries prepared from skin biopsies taken from resistant and susceptible Gyr x Holstein F2 animals. These biopsies were also used to study the expression level of these genes through real-time PCR analysis. The relative expression levels of the S100A7, TPT1, TRPV6, and CST6 genes were 2.01 ± 0.6, 1.32 ± 0.9, 1.53 ± 1.2, and 2.03 ± 0.7 times higher in the susceptible group, respectively. Skin lesion tissue from the susceptible animals showed significantly more mRNA transcripts of these genes in comparison with the resistant animals (P = 0.001). However, this hypersensitivity does not seem to protect the susceptible animals against tick infestation.

Evaluation of the efficacy of strains of Steinernema carpocapsae Santa Rosa and ALL (Steinernematidae: Rhabditida) to control engorged female Anocentor nitens (Acari: Ixodidae).

In view of the need to combat the generalized spread of resistance in ticks to commercial acaricides, the objective of this study was to evaluate the action of entomopathogenic nematodes (Steinernema carpocapsae, strains Santa Rosa and ALL) on engorged female Anocentor nitens. Five ticks per Petri dish were exposed to concentrations of 500, 5,000, or 25,000 infective juveniles of S. carpocapsae for 72 h. After transferring the ticks to clean plates, biological parameters were analyzed. Related to strains Santa Rosa, the period of pre-oviposition (p = 0.0001), oviposition (p = 0.041), and the mass weight of eggs (p = 0.005) showed significant differences between the control group and treated group. When the strain ALL was tested, the control and treated groups differed between the periods of pre-oviposition (p = 0.001), oviposition (p = 0.001), and egg mass weight (p = 0.01). The egg mass conversion was less significant in the groups when exposed to strains Santa Rosa (p = 0.002) and ALL (p = 0.001) relative to the control. The efficacy of both entomopathogenic nematode strains used in this study was comparable to other biological control agents, showing their potential against A. nitens in the laboratory.

A bovine-specific FSH enzyme immunoassay and its application to study the role of FSH in ovarian follicle development during the postnatal period.

The primary aim of this study was to develop a FSH enzyme immunoassay (EIA) for the bovine species. The newly developed EIA was validated for FSH determination in bovine plasma by comparison with an existing bovine FSH radioimmunoassay. The EIA detected bovine FSH with a high sensitivity (0.1 ng/ml). Cross-reactivity of the EIA was 0.01% with bovine LH, 51% with ovine FSH, <0.1% with porcine FSH and <0.01% with equine FSH. Using this EIA on different time series of plasma in cows, we have confirmed the presence of a FSH pre-ovulatory peak at estrus, of periodic FSH fluctuations accompanying the waves of terminal follicular development, and of FSH pulses, mainly asynchronous with LH ones, in the peri-ovulatory phase of the cycle. In a second objective, the EIA was used to assess the role of FSH in regulating the development of ovarian follicles up to the small antral stage in young calves. To answer this question, six calves were submitted to weekly blood sampling during their first 3 months of life, and FSH changes were studied concomitantly to those of anti-Müllerian hormone (AMH), a well-established endocrine marker of the ovarian population of small antral follicles in cows. In the ovaries of 3-month calves, the population of 3 to 5 mm follicles contained the highest intra-follicular AMH amounts, and the number of 3 to 5 mm follicles on ovaries was closely correlated with AMH concentrations in the plasma of calves at this age (rs = 0.94). Before 3 months of age, only two out of six calves showed a clear postnatal FSH peak in plasma, and no correlation was found between plasma FSH and AMH concentrations. These results indicate that female calves undergo different patterns of FSH secretion and that postnatal activation of follicular growth up to the small antral stage appears independent and not directly related to circulating FSH levels.

The role of higher polythionates in the reduction of chromium(VI) by Acidithiobacillus and Thiobacillus cultures.

In this paper, we report the chromium(VI) reduction by filtrates of Acidithiobacillus and Thiobacillus cultures. Chromium(VI) reduction by filtrates of A. ferrooxidans cultures under acidic conditions was higher than that observed for A. thiooxidans. However, at pH close to 7, chromium(VI) reduction by filtrates of T. thioparus cultures was as high as that by filtrates of A. thiooxidans cultures and much higher than that observed for A. ferrooxidans cultures at the same pH. The capability of these cultures to reduce chromium(VI) was associated specifically with the fraction of cultures (cells, sulphur and associated sulphur compounds) retained by filtration through a 0.45mum filter. In the fraction that comes from A. thiooxidans culture, polythionates (S(x)O(6)(2-)) with 3-7 sulphur atoms were detected and identified (by HPLC with MS as detector). The model of vesicles containing polythionates, sulphur and water agrees with our results.

Association of BoLA-DRB3.2 alleles with tick (Boophilus microplus) resistance in cattle.

Losses caused by bovine tick burdens in tropical countries have a tremendous economic impact on production systems. Besides reducing production, this parasite can cause death in the most susceptible animals. The use of commercial acaricides has been the major method of control, but their misuse has led to tick resistance to many chemicals. More recently, vaccines have been used in some countries without solving the problem completely. An alternative could be the development of resistant animals and the use of genetic markers and candidate genes that could help with the enormous task of selecting resistant animals. The bovine lymphocyte antigen genes (BoLA) have been shown to be associated with some parasitic infestations and disease incidence. Thus, the objective of the present study was to determine the association of BoLA-DRB3.2 alleles with tick resistance in cattle. The study was conducted on 231 F2 (Gyr x Holstein) animals that were artificially infested with 10,000 tick larvae. Log of tick count +1 was used as the dependent variable in a mixed animal model with allele substitution effects in addition to fixed effects of year and season at tick count, sex of calves, age of animal at tick count, hair type (short-straight, short-curl, long-straight, and long-curl), coat color (white, >75% white, 50- 75% white, and 25-50% white), and additive genetic, permanent environmental and residual effects as random. Females showed fewer ticks than males. Animals with short-straight hair were more resistant to tick infestation than animals with long-curl hair, and animals with whiter coat color also had fewer ticks. An association between BoLA alleles and lower tick number was found for alleles DRB3.2 *18, *20 and *27 at the 5% significance level. Also, one allele (DRB3.2*16) showed an association at the 10% level. Allele *27 was the most frequent in the population (30.7%), followed by alleles *16 (10.8%), *20 (8.7%) and *18 (2.4%). These results suggest that BoLA-DRB3.2 alleles could be used to help in the selection of animals resistant to tick infestation. However, further studies involving a larger population of cattle in combination with other BoLA genes may help to understand the mechanisms of resistance to parasites.

Assessment of weight gain and control of parasitism by Rhipicephalus microplus in dairy cattle in the field using organosynthetic parasiticide, phytotherapics and homeopathy / Avaliação do ganho de peso e controle do parasitismo por Rhipicephalus microplus em bovinos leiteiros a campo usando parasiticida organosintético, fitoterápicos e homeopatia

The goal of this research was to compare the effect of the following products on dairy cattle, parasitized by Rhipicephalus microplus: organosynthetics - Clorfenvinfós and Ivermectina (OG); phytotherapics - Eucalyptus oil (EG) and Neem cake (NG); Homeopathy (HG); The control group (CG) received no treatment. Infestation was by R. microplus (MIC) and weight gain (GP) were evaluated. The study included 60 animals (5 groups) from ­ Dutch / Zebu, aged between 25-44 months and initial weight between 211-477kg. EG and NG showed MIC 84.9% and 14.0% greater than CG, respectively (P <0.05; P = 0). HG and OG had MIC less than CG 24.4% and 16.9%, respectively (P<0.05; P <0.05). EG, NG and OG obtained GP lower than CG in 7.9%, 8.9% and 8.06% (P <0.05) respectively. The HG GP was 4.9% higher (P <0.05) than CG. This was the first research to prove parasitism control by R. microplus in a field test, using homeopathy. The methodology for choosing Homeopathy for the control of enzooties, developed and tested for the first time in this study, proved to be adequate and efficient, opening the possibility for establishing a new methodology for strategic control of parasitism by R. microplus.(AU)

O objetivo desta pesquisa foi comparar o efeito dos seguintes produtos sobre bovinos leiteiros, parasitados por Rhipicephalus microplus: organossintéticos - clorfenvinfós e ivermectina (OG); fitoterápicos - óleo de eucalipto (EG) e torta de Neem (NG) e homeopatia (HG). O grupo controle (CG) não recebeu tratamento. Foram avaliados infestação por R. microplus (MIC) e ganho de peso/grupo (GP) em 60 animais (5 grupos), a partir de ­ holandês/zebu, com idade entre 25 e 44 meses e peso inicial entre 211 e 477kg. EG e NG apresentaram MIC 84,9% e 14,0% maior que CG, respectivamente (P<0,05; P=0). HG e OG apresentaram MIC menor que CG 24,4% e 16,9%, respectivamente (P<0,05; P<0,05). EG, NG e OG obtiveram GP menor que CG em 7,9%, 8,9% e 8,06% (P<0,05), respectivamente. O GP do HG foi 4,9% maior (P<0,05) que o CG. Esta foi a primeira pesquisa a comprovar controle do parasitismo por R. microplus em teste a campo, usando homeopatia. A metodologia para escolha de medicamentos homeopáticos para controle de enzootias, desenvolvida e testada pela primeira vez neste estudo, mostrou-se adequada e eficiente, abrindo a possibilidade para estabelecimento de nova metodologia para controle estratégico do parasitismo por R. microplus.(AU)

Fulminant multiple system atrophy in a young adult presenting as motor neuron disease.

A 34-year-old man demonstrated rapidly progressive motor neuron disease and, late in his 9-month clinical course, exhibited ophthalmoplegia and dysautonomic symptoms. Neuropathology showed spinal and bulbar motor neuron disease with severe involvement of extraocular motor nuclei, degeneration of spinal sympathetic and bulbar parasympathetic nuclei, striatonigral degeneration, and early olivopontocerebellar atrophy. This case underscores the diversity of multiple system atrophy and demonstrates an unusually rapid course in a young patient.

Efficiency of collisionally-activated dissociation and 193-nm photodissociation of peptide ions in fourier transform mass spectrometry.

For tandem mass spectrometry, the Fourier transform instrument exhibits advantages for the use of collisionally-activated dissociation (CAD). The CAD energy deposited in larger ions can be greatly increased by extending the collision time to as much as 120 s, and the efficiency of trapping and measuring CAD product ions is many times greater than that found for triple-quadrupole or magnetic sector instruments, although the increased pressure from the collision gas is an offsetting disadvantage. A novel system that uses the same laser for photodesorption of ions and their subsequent photodissociation can produce complete dissociation of larger oligopeptide ions and unusually abundant fragment ions. In comparison to CAD, much more internal energy can be deposited in the primary ions using 193-nm photons, sufficient to dissociate peptide ions of m/z > 2000. Mass spectra closely resembling ion photodissociation spectra can also be obtained by' neutral photodissociation (193-nm laser irradiation of the sample) followed by ion photodesorption.

New Marfanoid syndrome with craniosynostosis.

We report on a patient with various connective tissue abnormalities suggesting a distinctive disorder combining some features of the Marfan syndrome with craniosynostosis and other anomalies. A comparison is made with the Marfan syndrome and other phenotypically similar conditions.

Neural network analysis of serial cardiac enzyme data. A clinical application of artificial machine intelligence.

There has been a recent resurgence of interest in the study and application of computerized neural networks within the broad field of artificial intelligence. These "intelligent machines" are modeled after biological nervous systems and are fundamentally different from the many computerized expert systems that previously have been introduced as clinical decision-making aids. The authors describe a neural network designed and trained to predict the probability of acute myocardial infarction (AMI) based on the analysis of paired sets of cardiac enzymes. The neural network predicted 24 of 24 (100%) AMIs and 27 of 29 (93%) No-AMIs when compared with a pathologist's interpretation of the patient's laboratory data (P less than 0.000001). The authors attempted to validate the network's diagnoses by two independent methods. When compared with echocardiogram and EKG for diagnosis of AMI, the neural network agreed with the cardiologist's interpretation in 12 of 14 (86%) AMIs and 1 of 3 (33%) No-AMIs, but the correlation was not statistically significant. Using autopsy outcome for validation, the neural network agreed with the anatomic evidence in 24 of 26 (92%) AMIs and 4 of 6 (67%) No-AMIs (P = 0.001). The authors conclude that neural networks can be successfully applied to the analysis of cardiac enzyme data and suggest that broader applications exist within the domain of clinical decision support.

Differential effects of tumour promoters on the growth of normal human bronchial epithelial cells and human lung tumour cell lines.

The effects of the tumour promoter, 12-O-tetradecanoylphorbol-13-acetate (TPA) on the colony-forming efficiency and growth of normal human bronchial epithelial (NHBE) cells and five lung squamous carcinoma cell lines were compared in medium containing 1% foetal bovine serum. TPA (0.1-5.0 ng/ml) inhibited the growth of NHBE cells and one carcinoma cell line, while four of the five carcinoma lines were less sensitive to the growth inhibitory properties of TPA but were slightly inhibited at higher TPA concentrations. The responses of NHBE cells and carcinoma cells to TPA, and the related compounds, mezerein, 4-O-methyl TPA, and phorbol were then compared in serum-free medium. In general, the removal of serum from the medium increased the differences in the responses to TPA between normal and tumour cells. Two carcinoma lines inhibited by TPA in 1% serum were stimulated by TPA in the absence of serum. Mezerein and, to a lesser extent, 4-O-methyl TPA also produced differential responses in colony-forming efficiencies between tumour lines and NHBE cells. Phorbol had no effect on either NHBE cells or on carcinoma cell lines. The relative insensitivity of carcinoma cell lines to the growth inhibitory effects of tumour promoters is consistent with the hypothesis that tumour promotion involves selection against normal cells to permit clonal expansion of preneoplastic or neoplastic cell types.

Oxidation of di- and tripeptides of tyrosine and valine mediated by singlet molecular oxygen, phosphate radicals and sulfate radicals.

Kinetics and mechanism of the oxidation of tyrosine (Tyr) and valine (Val) di- and tripeptides (Tyr-Val, Val-Tyr and Val-Tyr-Val) mediated by singlet molecular oxygen [O(2)((1)Delta(g))], phosphate (HPO(4)(*-) and PO(4)(*2-)) and sulfate (SO(4)(*-)) radicals was studied, employing time-resolved O(2)((1)Delta(g)) phosphorescence detection, polarographic determination of dissolved oxygen and flash photolysis. All the substrates were highly photooxidizable through a O(2)((1)Delta(g))-mediated mechanism. Calculated quotients between the overall and reactive rate constants for the quenching of O(2)((1)Delta(g)) by Tyr-derivatives (k(t)/k(r) values, accounting for the efficiency of the effective photooxidation) were 1.3 for Tyr, 1 for Tyr-Val, 2.8 for Val-Tyr and 1.5 for Val-Tyr-Val. The effect of pH on the kinetics of the photooxidative process confirms that the presence of the dissociated phenolate group of Tyr clearly dominates the O(2)((1)Delta(g)) quenching process. Products analysis by LC-MS indicates that the photooxidation of Tyr di- and tripeptides proceeds with the breakage of peptide bonds. The information obtained from the evolution of primary amino groups upon photosensitized irradiation is in concordance with these results. Absolute rate constants for the reactions of phosphate radicals (HPO(4)(*-) and PO(4)(*2-), generated by photolysis of the P(2)O(8)(4-) at different pH) and sulfate radicals (SO(4)(*-), produced by photolysis of the S(2)O(8)(2-)) with Tyr peptides indicate that for all the substrates, the observed tendency in the rate constants is: SO(4)(*-) > or = HPO(4)(*-) > or = PO(4)(*2-). Formation of the phenoxyl radical of tyrosine was detected as an intermediate involved in the oxidation of tyrosine by HPO(4)(*-).

A survey of dairy cattle worm control practices in southeast Brazil.

A survey on the nematode control strategies utilized by dairy farmers in Southeastern Brazil, a region accounting for 46.4% of the national milk production, was conducted through interviews with farmers. To select the producers to be interviewed the region was split into 16 non-contiguous clusters, according to the level of milk production. A systematic sample was then selected in each of the clusters. The interview questionnaire consisted of one-way, multiple-choice and open-ended questions. Data collected were represented by numbers and digitized on a data base (Epi Info, version 5.01b) and analyzed. Out of the 89 farmers interviewed, 37.5% deworm their herd after clinical signs and 62.5% preventively. Generally, anthelmintics are applied from one to 12 times a year (average of 3.79 times a year) in all age categories of animals. Of the anthelmintics used in the last deworming, imidazothiazole was used exclusively by 17.1% of the farmers, benzimidazole by 9.8% and avermectin by 18.3%, while 55.8% used more than one anthelmintic class to deworm their animals. To choose the dosage, most farmers consult the product label (94.8%) and determine the volume to be applied, based on an estimate of the average body weight of each animal (62.9%). Improvements in the general appearance of the herd and weight gains of growing animals were observed by most farmers after deworming (87.3%). However, most of them (66.2%) recalled interrupting the use of some compound in the last few years, due to the detection of no improvement following treatment (32.7%), rising costs of the medication (28.6%), adverse reaction (8.2%), product not available at the time of purchase (4.1%) and decision to change the compound in use (10.2%). Most farmers (95.3%) intend to continue using the same control measures in the following year. Veterinarians play an important role in the farmer's choice to deworm their animals, as many seek advice from them. Therefore, programs aimed at technology transfer should include continuous updates on the subject, especially for veterinarians.