Immunohistochemical evaluation of fibrin/fibrinogen, d-dimers, and intravascular thrombosis in brains of dogs with meningoencephalitis of unknown origin

Granulomatous meningoencephalitis (GME) and necrotizing encephalitides (NE) are the most common immune-mediated inflammatory diseases of the central nervous system in dogs. Activation of the fibrinolytic system in multiple sclerosis, a similar immune-mediated disease affecting the central nervous system in humans, seems to be related to disease progression. The aim of this study was to identify fibrin/fibrinogen and D-dimer deposition, as well as presence of intravascular thrombosis (IVT) in brains of dogs with a diagnosis of GME or NE. Immunohistochemical studies using antibodies against fibrin/fibrinogen and D-dimers were performed. Statistical analyses were performed to determine whether there were differences in the presence and location of fibrin/fibrinogen, D-dimers deposits, and IVT between GME and NE. Samples from sixty-four dogs were included in the study: 32 with a diagnosis of GME and 32 with a diagnosis of NE. Fibrin/fibrinogen depositions were detected in all samples and d-dimers were detected in 43/64 samples. IVT was present in 29/64 samples, with a significantly higher score in samples from dogs with NE than in samples from dogs with GME (P = 0.001). These data support hemostatic system activation in both diseases, especially NE. This finding might be related to the origin of the necrotic lesions seen in NE, which could represent chronic ischemic lesions. Further studies are needed to investigate the association between vascular lesions and the histopathological differences between GME and NE and the hemostatic system as a potential therapeutic target.

Cardiac Optimal Point: Identifying high risk patients for an optimal approach

Funding Acknowledgements

Type of funding sources: None.

Introduction

In recent years it has been proposed the concept of cardiorespiratory optimal point (COP) to best characterize populations who underwent cardiac rehabilitation programmes (CRP). The COP is defined as the minimum ratio between ventilation and oxygen consumption (VE/VO2) obtained during the cardiopulmonary exercise test (CPET) and it has been suggested that COP values > 30 conveyed worse prognosis.

Purpose

To validate OP as a predictor of events and its correlation with exercise activity and quality of life on the long term.

Methods

Single center observational study of patients enrolled on CRP - from February 2018 to May 2019 – who did CPET as part of routine evaluation. COP was defined as the lowest point of VE/VO2 ratio. Clinical and laboratorial characteristics were obtained at admission and discharge of CRP. Exercise practice was accessed using IPAQ questionnaire and quality of life was assessed based on a validated inquire - Kansas City Cardiomyopathy Questionnaire (KCCQ-23) – both by phone interview.

Results

A total of 78 patients (mean age 63.2 ±11.6, 84.6% male) were evaluated and followed for a mean follow-up of 2,68±0,53 years. Main aetiology was ischemic heart disease (86%), followed by dilated cardiomyopathy (5,1%) and valvular heart disease (2,6%).

A COP value above 30 correlated with a worse global score in KCC-23 (r =0.283, p = 0.47), and in particular domains such as frequency and severity of symptoms (p = 0.046, r 0.335 and p=0.16, r= 0.4, respectively), quality of life (p=0.039, r= 0.293) and social limitation (p = 0.001, r=0.5). COP also correlated with VO2 peak in basal CPET (p<0.001, r= 0.450) and on follow-up CPET (p= 0.39, r= 0.303).

COP failed to predict events or levels of exercise activity on the long term, as evaluated by the IPAQ score. However, COP>30 did seem to correlate with a higher mortality rate on the follow-up although such trend was not statistically significant (possibly due to short follow-up time and sample size).

Conclusion

COP values > 30 identify patients with worse prognosis, predicting worse quality of life and higher mortality. Although it did not seem to be a good predictor of exercise adherence after CRP.

Mitochondrial DNA haplogroups and age at onset of Machado-Joseph disease/spinocerebellar ataxia type 3: a study in patients from multiple populations

BACKGROUND AND PURPOSE

Mitochondrial dysfunction has been implicated in the pathogenesis of several neurodegenerative disorders, including Machado-Joseph disease (MJD), an autosomal dominant late-onset polyglutamine ataxia that results from an unstable expansion of a CAG tract in the ATXN3 gene. The size of the CAG tract only partially explains age at onset (AO), highlighting the existence of disease modifiers. Mitochondrial DNA (mtDNA) haplogroups have been associated with clinical presentation in other polyglutamine disorders, constituting potential modifiers of MJD phenotype.

METHODS

A cross-sectional study, using 235 unrelated patients from Portugal, Brazil, India and Japan, was performed to investigate if mtDNA haplogroups contribute to AO of MJD. mtDNA haplogroups were obtained after sequencing the mtDNA hypervariable region I. Patients were classified in 15 phylogenetically related haplogroup clusters.

RESULTS

The AO was significantly different among populations, implying the existence of other non-CAG factors, which seem to be population specific. In the Portuguese population, patients classified as belonging to haplogroup JT presented the earliest onset (estimated onset 34.6 years of age). Haplogroups W and X seem to have a protective effect, causing a delay in onset (estimated onset 47 years of age). No significant association between haplogroup clusters and AO was detected in the other populations or when all patients were pooled. Although haplogroup JT has already been implicated in other neurodegenerative disorders, no previous reports of an association between haplogroups W and X and disease were found.

CONCLUSIONS

These findings suggest that haplogroups JT, W and X modify AO in MJD. Replication studies should be performed in European populations, where the frequency of the candidate modifiers is similar.

Prevalence of late-onset pompe disease in Portuguese patients with diaphragmatic paralysis - DIPPER study

Pompe disease is a rare autosomal recessive neuromuscular disorder caused by acid α-glucosidase enzyme (GAA) deficiency and divided into two distinct variants, infantile- and late-onset. The late-onset variant is characterized by a spectrum of phenotypic variation that may range from asymptomatic, to reduced muscle strength and/or diaphragmatic paralysis. Since muscle strength loss is characteristic of several different conditions, which may also cause diaphragmatic paralysis, a protocol was created to search for the diagnosis of Pompe disease and exclude other possible causes.

METHODS

We collected a sample size of 18 patients (10 females, 8 males) with a median age of 60 years and diagnosis of diaphragmatic paralysis of unknown etiology, followed in the Pulmonology outpatient consultation of 9 centers in Portugal, over a 24-month study period. We evaluated data from patient's clinical and demographic characteristics as well as complementary diagnostic tests including blood tests, imaging, neurophysiologic and respiratory function evaluation. All patients were evaluated for GAA activity with DBS (dried blood test) or serum quantification and positive results confirmed by serum quantification and sequencing.

RESULTS

Three patients were diagnosed with Pompe's disease and recommended for enzyme replacement therapy. The prevalence of Pompe, a rare disease, in our diaphragmatic paralysis patient sample was 16.8%.

CONCLUSION

We conclude that DBS test for GAA activity should be recommended for all patients with diaphragmatic paralysis which, despite looking at all the most common causes, remains of unknown etiology; this would improve both the timing and accuracy of diagnosis for Pompe disease in this patient population. Accurate diagnosis will lead to improved care for this rare, progressively debilitating but treatable neuromuscular disease.

Study of in situ adsorption kinetics of polyelectrolytes and liposomes using quartz crystal microbalance: Influence of experimental layout

Quartz Crystal Microbalance (QCM) is a widely used technique to characterize adsorption/desorption phenomena at the solid/liquid interface. However, the obtained adsorption/desorption kinetics curves are often not reproducible and present some noise and long term fluctuations. In this work, the accuracy of a commercial QCM to measure the adsorbed amount of polyelectrolytes and biological molecules was evaluated in terms of experimental QCM configurations with respect to quality, stability, and reproducibility of the measured data. Evaluation consisted in comparing the adsorption kinetics curves of the cationic polyelectrolyte poly(ethyleneimine) and the anionic 1,2-dipalmitoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (sodium salt) liposomes, when setting the quartz crystal surface in stationary horizontal open, stationary horizontal closed, stationary vertical open, continuous vertical closed, and stationary vertical closed measuring configuration. For this last configuration, a new cell was designed and implemented. The analysis of the kinetics curves revealed that horizontal modes are more unstable when subjected to fostering noise due to the mechanical vibrations and lead to resonance frequency shift. This shift is caused by the measurement of non-adsorbed molecules which are deposited on the quartz crystal due to gravity force. The vertical modes proved to be more reproducible and reliable.

Determination of degree of ionization of poly(allylamine hydrochloride) (PAH) and poly[1-[4-(3-carboxy-4 hydroxyphenylazo)benzene sulfonamido]-1,2-ethanediyl, sodium salt] (PAZO) in layer-by-layer films using vacuum photoabsorption spectroscopy

Electrostatic and hydrophobic interactions govern most of the properties of supramolecular systems, which is the reason determining the degree of ionization of macromolecules has become crucial for many applications. In this paper, we show that high-resolution ultraviolet spectroscopy (VUV) can be used to determine the degree of ionization and its effect on the electronic excitation energies of layer-by-layer (LbL) films of poly(allylamine hydrochloride) (PAH) and poly[1-[4-(3-carboxy-4 hydroxyphenylazo)benzene sulfonamido]-1,2-ethanediyl, sodium salt] (PAZO). A full assignment of the VUV peaks of these polyelectrolytes in solution and in cast or LbL films could be made, with their pH dependence allowing us to determine the pK(a) using the Henderson-Hasselbach equation. The pK(a) for PAZO increased from ca. 6 in solution to ca. 7.3 in LbL films owing to the charge transfer from PAH. Significantly, even using solutions at a fixed pH for PAH, the amount adsorbed on the LbL films still varied with the pH of the PAZO solutions due to these molecular-level interactions. Therefore, the procedure based on a comparison of VUV spectra from solutions and films obtained under distinct conditions is useful to determine the degree of dissociation of macromolecules, in addition to permitting interrogation of interface effects in multilayer films.

273 OVUM PICKUP AT DIFFERENT TIMES OF A SYNCHRONIZED FOLLICULAR WAVE DID NOT AFFECT IVP IN BOS INDICUS, BOS TAURUS, OR BUBALUS BUBALIS

One important factor in the success of ovum pickup (OPU)/IVP in Bos taurus is the follicular status at OPU concerning the dominance period (Hendriksen et al. 2000 Theriogenology 53, 11-20). The hypothesis of the present study is that OPU performed after follicle deviation, when follicles show a mild level of atresia, improves competence for IVP in Nelore (NE), Holstein (HO), and buffaloes (BU). Objectives were to determine effects of OPU done at different times of synchronized follicular wave (1, 3, or 5 d after expected emergence) and of genetic group (NE, HO, and BU) on IVP. A total of 27 heifers (9 of each genetic group) were maintained in contemporary nutritional and environmental conditions during experiment, in a cross-over design, performed in 6 replicates. Recovered oocytes with at least one cumulus cell layer were matured in TCM-199 supplemented with 10% of FCS plus 50 μM of cysteamin and 0.3 mM of cystine, at 38.5°C with 5% CO2 in air for 24 h. IVF was done with 2 × 106 spermatozoa per mL of NE (for bovine oocytes) or BU semen (for BU oocytes), for 20 h at the same incubator conditions of IVM. After IVF, presumptive zygotes were denuded and cultured in SOF under the same previous atmosphere conditions. Medium was changed 3 d after IVF when cleavage rate (CR) was assessed. Blastocyst (BR) and hatching rates (HR) were evaluated 7 and 9 days after IVF, respectively. About 50% of hatched blastocysts were fixed until nuclei counting. Data were analyzed by ANOVA using the Proc Mixed model. No effects of interaction or time of synchronization were observed in any of the variables. Concerning genetic group, NE had better results than HO and BU (mean ± SEM / heifer / replicate), respectively, for visualized follicles (41.0a ± 2.1, 22.1b ± 1.3, 18.8b ± 0.9), total oocytes (37.1a ± 2.5, 15.4b ± 1.2, 14.8b ± 1.0), oocytes at IVM (30.8a ± 2.4, 10.7b ± 1.0, 7.9b ± 0.7), oocytes at IVC (18.7a ± 0.8, 8.0b ± 0.5, 7.5b ± 0.4), cleaved embryos (15.4a ± 0.7, 4.6b ± 0.4, 4.4b ± 0.3),CR(81.8a, 59.1b, 62.3b), blastocysts on Day 7 (5.1a ± 0.6, 1.0b ± 0.2, 0.6b ± 0.1), BR (25.8a, 13.6b, 9.1b), and hatched blastocysts on Day 9 (2.6a ± 0.4, 0.3b ± 0.1, 0.3b ± 0.1). Recovery rate and HR were greater for NE (89.4 and 50.6%, respectively) than for HO (73.3 and 23.2%), but neither differed from BU (82.8 and 31.9%). Also, the percentage of viable was greater for NE (83.0) than for HO (66.9) and BU (53.1). No effects were observed for nuclei counting (NE = 176.6 ± 5.3, HO = 168.9 ± 13.7 and BU = 206.1 ± 23.1). Results demonstrate that Nelore had a better efficiency for IVP than Holstein and buffaloes. OPU performed at different times of synchronized follicular wave did not influence IVP, conversely to the initial hypothesis of this study. FAPESP (06/59550-6, 07/04782-2), Tortuga Cia Zootecnica®, Santa Adele and São Caetano Farms, LMMD, PCAPS, HOVET (Dr. Ubiraem Schalch), VRA, VNP (Prof. Dr. Francisco de Palma Rennó).

353 CUMULUS CELLS RESPONSE TO HEAT SHOCK AND INSULIN-LIKE GROWTH FACTOR-I

Heat-stress induced maternal hyperthermia has been shown to compromise the series of events associated with oocyte growth and maturation reducing oocyte competence. Such events are regulated by a variety of growth factors and dynamic communication between the oocyte and its surrounding cumulus cells. The objective of the current study was to evaluate the modulatory effects of COCs quality and IGF-I on mitochondrial membrane potential (MMP) and apoptosis in cumulus cells induced by heat shock. In this study high (≥3 layers of compact cumulus cells and homogeneous cytoplasm) and low-grade COCs (<3 layers of less compact cumulus cells and irregular cytoplasm) derived from slaughterhouse ovaries were exposed to control (CTR: 39°C) or heat shock (HS: 41°C) treatments in the presence of 0 or 100 ng mL-1 IGF-I during the first 12 h of in vitro maturation (12 h-IVM). Immediately after 12 h-IVM COCs were denuded by repeated pipetting and cumulus cells evaluated for MMP (MitoProbe JC-1 assay kit. JC-1 is a cationic dye that exhibits potential-depend accumulation in the mitochondria) and apoptosis (Annexin V-FITC and propidium iodide) by flow cytometry (Guava EasyCyte Mini Flow Cytometry System, Millipore, Billerica, MA, USA). This factorial experiment was replicated 4 times using 75-100 COCs per treatment. Data were subjected to three-way analysis of variance using the General Linear Models procedure of SAS. Results are shown in Table 1. Exposure of high and low-grade COCs to HS reduced (P < 0.01) the percentage of cumulus cells carrying high MMP regardless of IGF-I. Even though HS caused cumulus cells mitochondrial membrane depolarization there was neither temperature nor COCs quality effect on cumulus cells apoptosis as indicated by the lack of phosphatidylserine (PS) translocation from the inner to the outer leaflet of the plasma membrane. On the other hand, addition of IGF-I to maturation medium reduced (P < 0.05) the percentage of cumulus cells labeled with Annexin V + PI regardless of COCs quality or temperature. There was no statistical interaction between COCs quality × IGF-I × temperature. In conclusion, exposure of COCs to HS during 12 h-IVM caused cumulus cells mitochondrial depolarization without inducing apoptosis. It is possible that a period longer than 12 h is required for most PS translocation to occur in cumulus cells. Moreover, IGF-I exerted protective effect reducing cumulus cells late apoptosis/necrosis events. Table 1.Effect of heat-shock and IGF-I on cumulus cells mitochondrial membrane potential and apoptosis. Results are least-squares means ± SEM.

VUV spectroscopy of water under cellular conditions

The understanding of radiation damage within cells, and thence mutagenesis, depends upon a detailed knowledge of the spectroscopy and dissociation dynamics of water. Results of a new study of the electronic state spectroscopy of water, using synchrotron radiation are reported. In order to gain some insight into how the spectroscopy and dissociation dynamics of water is influenced by its environment we also report photo-absorption spectra of water within thin films of poly(o-methoxyaniline) which have been suggested as a good mimic for biological membranes in the cellular environment. Comparison of these spectra with those of gaseous water and condensed amorphous water ice suggest that water in such films is similar to gaseous water and does not show the blue shift suggested in some cellular models. The lowest energy of OH production from dissociation of water in the cellular environment may therefore be around 6.7 eV (185 nm).

Absence of hepatitis C virus transmission in a prospective cohort of heterosexual serodiscordant couples

OBJECTIVE

To analyse hepatitis C virus (HCV) transmission in a cohort of heterosexual couples who are discordant both for HIV and for HCV.

METHODS

We followed an open cohort of 171 people, 152 women and 19 men, who were not initially infected by either HIV or HCV, and whose steady heterosexual partner presented antibodies to both viruses (index case). Other risk exposures were excluded. Every 6 months clinical, epidemiological, and risk behaviour information was collected, and antibodies to both viruses were determined.

RESULTS

During 529 person years of follow up more than 40 000 vaginal or anal penetrations were recorded. 74 partners (43.3%) had vaginal and/or anal intercourse without condoms with the index case; another 15.8%, who always used condoms, declared breaking or slipping episodes during intercourse; and another 22.2% had unprotected orogenital exposures. During the follow up, over 5800 unprotected vaginal and anal contacts with the index case were estimated, as well as more than 25 000 unprotected orogenital contacts. 31 women became pregnant (two were index cases), and seroconversion to HIV occurred for one woman (1.7 per 10 000 unprotected contacts; 95% CI, 0 to 9.5), but there was no seroconversion to HCV (95% CI, 0-6.3 per 10 000 unprotected contacts).

CONCLUSION

These results are consistent with a low or null transmissibility of HCV in heterosexual relations, even when the index case is HIV co-infected.

[Trends in human immunodeficiency virus infection prevalence in homosexual/bisexual men in Madrid (1986-1995)]

BACKGROUND

We analysed the trend in seroprevalence for human immunodeficiency virus (HIV) in homosexual or bisexual men who voluntary requested the test in a sexually transmitted disease/HIV clinic in Madrid.

PATIENTS AND METHODS

We studied 5,424 homo/bisexual non-injecting drug user (non-IDU) men, who came for the first time since 1986 to 1995. We analysed the HIV seroprevalence taken into account the year, age and exchange of sex by money. A hundred and thirty-six IDU homo/bisexual men were also attended during the same period and they were compared with non-IDU.

RESULTS

HIV seroprevalence among the 5,424 non-IDU homo/bisexual men were 20.2%, rising from 19.6% in 1986 to 29.6% in 1990. After then, the trend decreased to 15.3% in 1995 (chi 2 for trend, 66.8; p < 0.0001). Average age was three years higher among seropositives (p < 0.0001), and showed an upward trend from 29.9 in 1986 to 34.6 in 1995 (p = 0.0059). Seroprevalence among homosexuals younger than 25 fell in the last years. One percent of individuals had ever practiced the prostitution. They were younger (average age, 27.6), and their HIV seroprevalence were 25.9%. A hundred and thirty-six IDU homo/bisexual men were also attended for the first time, being 2.4% of overall homo/bisexual men. They had a higher seroprevalence (48.5%) than non-IDU (p < 0.0001), and did not show any significative time-trend.

CONCLUSIONS

A favourable evolution can be observed in HIV seroprevalence among homo/bisexual from Madrid, Spain, men who came to be tested, especially among the youngest. Prevention programs should make an effort to maintain this trend.

Relationship between multiple exposures to violence and coping strategies among African-American mothers

This exploratory study examined the relationship between coping strategies of 136 African-American mothers, their exposure to community violence, and their interpersonal victimization. It is suggested that the disproportionate victimization of African-American women produces a cumulative triple threat for those who live amidst conditions of community violence in the following manner: a) exposure through daily living in the midst of unpredictable community violence; b) exposure to violence from witnessing violence in the neighborhood; and c) exposure to violence from disproportionately high rates of personal victimization. The findings suggest that coping strategies are used differentially as a function of the amount of violence within the social context, and the education and financial resources of the mothers. Mothers who live in lower-violence areas with college education preferred activism as a coping strategy, whereas those in high-violence areas with comparable incomes and education preferred reliance on prayer and instituting safety practices. Coping strategies differed based on whether mothers had been physical victims and witnesses to violence or had no personal experience with violence. This study lays the groundwork for a model of exploring the impact of the cumulative effects of violence on African-American mothers parenting in urban America.

The mechanism of intracellular acidification induced by glucose in Saccharomyces cerevisiae

Addition of glucose or fructose to cells of Saccharomyces cerevisiae adapted to grow in the absence of glucose induced an acidification of the intracellular medium. This acidification appeared to be due to the phosphorylation of the sugar since: (i) glucose analogues which are not efficiently phosphorylated did not induce internal acidification; (ii) glucose addition did not cause internal acidification in a mutant deficient in all the three sugar-phosphorylating enzymes; (iii) fructose did not affect the intracellular pH in a double mutant having only glucokinase activity; (iv) glucose was as effective as fructose in inducing the internal pH drop in a mutant deficient in phosphoglucose isomerase activity; and (v) in strains deficient in two of the three sugar-phosphorylating activities, there was a good correlation between the specific glucose- or fructose-phosphorylating activity of cell extracts and the sugar-induced internal acidification. In addition, in whole cells any of the three yeast sugar kinases were capable of mediating the internal acidification described. Glucose-induced internal acidification was observed even when yeast cells were suspended in growth medium and in cells suspended in buffer containing K+, which supports the possible signalling function of the glucose-induced internal acidification. Evaluation of internal pH by following fluorescence changes of fluorescein-loaded cells indicated that the change in intracellular pH occurred immediately after addition of sugar. The apparent Km for glucose in this process was 2 mM. Changes in both the internal and external pH were determined and it was found that the internal acidification induced by glucose was followed by a partial alkalinization coincident with the initiation of H+ efflux. This reversal of acidification could be due to the activity of the H+-ATPase, since it was inhibited by diethylstilboestrol. Coincidence between internal alkalinization and the H+ efflux was also observed after addition of ethanol.