Evidence of elevated situational awareness for active duty soldiers during navigation of a virtual environment

U.S. service members maintain constant situational awareness (SA) due to training and experience operating in dynamic and complex environments. Work examining how military experience impacts SA during visual search of a complex naturalistic environment, is limited. Here, we compare Active Duty service members and Civilians' physiological behavior during a navigational visual search task in an open-world virtual environment (VE) while cognitive load was manipulated. We measured eye-tracking and electroencephalogram (EEG) outcomes from Active Duty (N = 21) and Civilians (N = 15) while they navigated a desktop VE at a self-regulated pace. Participants searched and counted targets (N = 15) presented among distractors, while cognitive load was manipulated with an auditory Math Task. Results showed Active Duty participants reported significantly greater/closer to the correct number of targets compared to Civilians. Overall, Active Duty participants scanned the VE with faster peak saccade velocities and greater average saccade magnitudes compared to Civilians. Convolutional Neural Network (CNN) response (EEG P-300) was significantly weighted more to initial fixations for the Active Duty group, showing reduced attentional resources on object refixations compared to Civilians. There were no group differences in fixation outcomes or overall CNN response when comparing targets versus distractor objects. When cognitive load was manipulated, only Civilians significantly decreased their average dwell time on each object and the Active Duty group had significantly fewer numbers of correct answers on the Math Task. Overall, the Active Duty group explored the VE with increased scanning speed and distance and reduced cognitive re-processing on objects, employing a different, perhaps expert, visual search strategy indicative of increased SA. The Active Duty group maintained SA in the main visual search task and did not appear to shift focus to the secondary Math Task. Future work could compare how a stress inducing environment impacts these groups' physiological or cognitive markers and performance for these groups.

Comparison of clinical presentations and burden of respiratory syncytial virus in infants across three distinct healthcare settings in Davidson County, Tennessee

Background:

The burden of respiratory syncytial virus (RSV)-associated acute respiratory illnesses among healthy infants (<1 year) in the inpatient setting is well established. The focus on RSV-associated illnesses in the outpatient (OP) and emergency department (ED) settings are however understudied. We sought to determine the spectrum of RSV illnesses in infants at three distinct healthcare settings.

Methods:

From 16 December 2019 through 30 April 2020, we performed an active, prospective RSV surveillance study among infants seeking medical attention from an inpatient (IP), ED, or OP clinic. Infants were eligible if they presented with fever and/or respiratory symptoms. Demographics, clinical characteristics, and illness histories were collected during parental/guardian interviews, followed by a medical chart review and illness follow-up surveys. Research nasal swabs were collected and tested for respiratory pathogens for all enrolled infants.

Results:

Of the 627 infants screened, 475 were confirmed eligible; 360 were enrolled and research tested. Within this final cohort, 101 (28%) were RSV-positive (IP = 37, ED = 18, and OP = 46). Of the RSV-positive infants, the median age was 4.5 months and 57% had ⩾2 healthcare encounters. The majority of RSV-positive infants were not born premature (88%) nor had underlying medical conditions (92%). RSV-positive infants, however, were more likely to have a lower respiratory tract infection than RSV-negative infants (76% vs 39%, p < 0.001). Hospitalized infants with RSV were younger, 65% required supplemental oxygen, were more likely to have lower respiratory tract symptoms, and more often had shortness of breath and rales/rhonchi than RSV-positive infants in the ED and OP setting.

Conclusion:

Infants with RSV illnesses seek healthcare for multiple encounters in various settings and have clinical difference across settings. Prevention measures, especially targeted toward healthy, young infants are needed to effectively reduce RSV-associated healthcare visits.

290. Persistence of Long COVID in SARS-CoV-2 Confirmed Cases One-Year Post Infection

Background

Regardless of severity of acute SARS-CoV-2 illness, adults infected with SARS-CoV-2 are at risk for post-acute sequelae of COVID-19. Long COVID is typically classified as symptoms lasting greater than four weeks post-infection. We aimed to evaluate the frequency of resolved and unresolved long COVID symptoms in adults residing in greater Nashville, TN.

Methods

We conducted a longitudinal cohort study of SARS-CoV-2-positive and exposed individuals from March 20 to May 15, 2020. Participants for this analysis were included if: 1) ≥18 years; 2) SARS-CoV-2 positive by molecular or antibody testing; and 3) completed a one-year visit. Demographic and illness information were collected at enrollment, and long COVID symptoms were systematically collected at the one-year survey. Long COVID symptoms are defined as an adult experiencing at least one of the following symptoms four weeks post-infection: fatigue, confusion, loss of smell or taste, shortness of breath, chest pain, cough, muscle aches, inability to exercise, or heart palpitations. Unresolved symptoms are defined as an individual with long COVID still experiencing symptoms at the one-year visit.

Results

A total of 115 adults enrolled and completed the one-year survey, of which 63 (54.8%) were SARS-CoV-2-positive, with one asymptomatic individual. Of SARS-CoV-2-positive symptomatic adults, 32 (51%) were female, 5 (88%) were of Hispanic ethnicity, and 58 (92%) were white. At the one-year visit, 33 (52%) reported having long COVID, of which 17 (52%) reported having unresolved symptoms. Fatigue (89%), headache (89%), muscle aches (79%), and cough (77%) were the most common symptoms reported at illness onset (Figure 1). Among 33 adults with long COVID, fatigue (42%), loss of smell (39%), and loss of taste (33%) were most common (Figure 2A). In the 17 individuals with unresolved symptoms, loss of smell (29%) and loss of taste (24%) were commonly reported (Figure 2B).

Figure 1. COVID-19 symptoms reported at enrollment (n=62)

Figure 2. Long COVID (symptoms lasting ≥ 4 weeks) (n=33) (A) and unresolved long COVID symptoms one-year post-infection (n=17) (B) reported on the one-year survey

Conclusion

Half of the adults in our cohort reported long COVID symptoms, with more than quarter of symptoms persisting one-year post-illness. Our findings support that prolonged symptoms up to year after SARS-CoV-2 exposure occur, and future studies should investigate the residual impacts of long COVID symptoms and conditions.

Disclosures

Natasha B. Halasa, MD, MPH, Genentech (Other Financial or Material Support, I receive an honorarium for lectures - it’s a education grant, supported by genetech)Quidel (Grant/Research Support, Other Financial or Material Support, Donation of supplies/kits)Sanofi (Grant/Research Support, Other Financial or Material Support, HAI/NAI testing) Natasha B. Halasa, MD, MPH, Genentech (Individual(s) Involved: Self): I receive an honorarium for lectures - it’s a education grant, supported by genetech, Other Financial or Material Support, Other Financial or Material Support; Sanofi (Individual(s) Involved: Self): Grant/Research Support, Research Grant or Support

581. COVID-19 Vaccine Perceptions in Adults from Greater Nashville Tennessee

Background

In December 2020, SARS-CoV-2 vaccines were made available to healthcare workers and soon thereafter offered to the general public according to age and risk of severe illness. Despite widespread access, vaccination rates vary by region, with Tennessee ranking lower than the national average. Therefore, we aimed to survey adults in greater Nashville, TN regarding SARS-CoV-2 vaccine perceptions.

Methods

We conducted a cross-sectional study of an ongoing longitudinal cohort of individuals with confirmed and/or suspected SARS-CoV-2 infection and their household contacts with enrollment onset in March 2020. For this analysis, individuals were included if they were ≥ 18 years and available for a one-year follow-up visit. At the one-year visit individuals completed a survey about vaccine preferences, beliefs and risks. Demographic and social characteristics were collected at enrollment. Individuals were considered vaccinated if they had received at least one dose of a SARS-CoV-2 vaccine under FDA emergency use authorization. Vaccine perceptions were compared by SARS-CoV-2-infection and vaccination status using Pearson’s chi-squared, alpha=5%.

Results

Between April-May 2021, 115 individuals completed the one-year follow-up. Table 1 includes sociodemographic characteristics of adults, of which the majority were vaccinated and were unemployed or in non-essential occupations. Most individuals agreed the SARS-CoV-2 vaccine can prevent infection and hospitalization (Figure 1A & B). Unvaccinated participants more often agreed that those who contracted SARS-CoV-2 should not receive the vaccine (30%), whereas vaccinated persons less often agreed (11%, p< 0.001) (Figure 1A). Additionally, 44% of unvaccinated individuals were neutral or disagreed that benefits of SARS-CoV-2 vaccination outweighed the illness risk, compared to 10% in the vaccinated group, p=0.001 (Figure 1A). Minimal differences of vaccine perceptions were observed between SARS-CoV-2 positive and negative adults (Figure 1B).

Table 1. Sociodemographic Characteristics of Adults

Figure 1. Vaccine perceptions of vaccinated and unvaccinated (A) SARS-CoV-2 positive and SARS-CoV-2 negative (B) adults in greater Nashville, TN. Vaccine perceptions were collected through a standardized survey at the one-year visit.

Conclusion

Although some unvaccinated individuals seemingly perceived the SARS-CoV-2 vaccine offered some protection, research should continue to evaluate the implications of vaccine hesitancy on the COVID-19 pandemic response as we prepare for the upcoming respiratory season.

Disclosures

Natasha B. Halasa, MD, MPH, Genentech (Other Financial or Material Support, I receive an honorarium for lectures - it's a education grant, supported by genetech)Quidel (Grant/Research Support, Other Financial or Material Support, Donation of supplies/kits)Sanofi (Grant/Research Support, Other Financial or Material Support, HAI/NAI testing) Natasha B. Halasa, MD, MPH, Genentech (Individual(s) Involved: Self): I receive an honorarium for lectures - it's a education grant, supported by genetech, Other Financial or Material Support, Other Financial or Material Support; Sanofi (Individual(s) Involved: Self): Grant/Research Support, Research Grant or Support

Tuberculosis in children treated with second-line drugs under programmatic conditions in Lima, Peru

OBJECTIVE

To characterise childhood tuberculosis (TB) treated with second-line drugs (SLDs) in Lima, Peru.

DESIGN

Results for the age groups <5 and 5-14 years were compared and treatment outcomes were assessed in cases reported between 2011 and 2015 from six districts of Lima.

RESULTS

Of 96 reported cases, 82 were evaluated. Among these, 59% were boys; the median age was 8 years and 32% were aged <5 years. Contact with a TB case was reported in 82% of cases; 90% were treatment-naïve, 98% had pulmonary localisation and 50% underwent the tuberculin skin test (purified protein derivative), with induration 10 mm in 88%. A positive smear was found in 40%, all in the 5-14 years age group, and 46% were culture-positive. Only 26% had confirmed multidrug-resistant TB, 90% of whom were in the 5-14 years age group. SLDs for confirmed or probable drug-resistant TB (DR-TB) were administered to all cases, with a high proportion of success (over 83%), no failures or deaths and a high proportion of loss to follow-up.

CONCLUSION

The main indication for SLDs in childhood TB was the empirical treatment of DR-TB due to contact with one or more identified DR-TB patients. Bacteriological confirmation was limited; however, treatment success was adequate.

Acute tubulointerstitial nephritis associated with atezolizumab, an anti-programmed death-ligand 1 (pd-l1) antibody therapy

Direct stimulation of the antitumor activity of immune system through checkpoint inhibitors (ICIs) has demonstrated efficacy in the treatment of different cancer types. The activity of these antibodies takes place in the immunological synapse blocking the binding of the negative immunoregulatory proteins, thus leading to the finalization of the immune response. Despite having a favorable toxicity profile, its mechanism of action impedes the negative regulation of the immune activity which can potentially favor autoimmune attacks to normal tissues. Renal toxicity has been described in several ICI but not with atezolizumab, an IgG1 monoclonal antibody targeting PD-L1 (programmed death ligand 1), approved by FDA as a second-line therapy for advanced urothelial carcinoma. Here we present a patient with a single kidney and metastatic renal cell carcinoma treated with atezolizumab and bevacizumab combination, with biopsy-proven acute interstitial nephritis, who had a complete resolution of renal dysfunction after steroid therapy.

290 OPTIMAL OF DOSE OF OVINE PITUITARY GLAND EXTRACT OVAGEN® FOR SUPERSTIMULATION OF BEEF COW DONORS IN ARGENTINA

The success of an embryo transfer program is measured by the number of calves born alive by female donor in a given period. The success is influenced by several factors related to the number of ovulations, fertilization rate, and embryo viability (Armstrong D 1993 Theriogenology 39, 7–24). One of the main inconveniences of embryo transfer programs is the variability of superovulatory response to treatments. An experiment was designed to determine the optimal dose of ovine pituitary gland extract Ovagen® (ICPbio, Ltd., Auckland, New Zealand) for inducing superovulation in Aberdeen Angus donor cows. Sixty cycling multiparous donors with a condition score between 3.5 and 4.5 (Scale 1 to 5) were used. All donors received an intravaginal progesterone device DIB (1 g of Progesterone, Syntex, Buenos Aires, Argentina), along with 2 mg of EB (Estradiol Benzoate, Syntex, Buenos Aires, Argentina) and 50 mg of progesterone (Laboratorio Rio de Janeiro, Argentina) on Day 0. Superestimulatory treatment began on Day 4 and donors were randomly assigned to 3 treatment groups according to the total dose of NIADDK-oFSH-Z (Ovagen®) as follows: Group 1, cows received the total dose recommended by the manufacturer (100%* Group), 17.6 mg; Group 2, cows received 75% of the total dose recommended by manufacturer (75% Group), 13.2 mg and Group 3, cows received 50% of the total dose recommended by manufacturer (50% Group), 8.8 mg. All cows received two 150 μg of D+ cloprostenol IM (Ciclase, Syntex) injections on Day 6 given at 12 h interval. DIB was removed on Day 7 a.m. On Day 8 a.m., cows received 0.05 mg of GnRH IM (Gonasyn, Syntex). Fixed time AI was done on Day 8 p.m. and Day 9 a.m. with high quality frozen–thawed semen. On Day 15 embryo collection was performed by non-surgically method and evaluated by developmental stage and quality. The efficiency of superestimulatory response was evaluated by total amount of collected ova-embryos, fertilized ova and embryos Grade 1, 2, and 3, (according to IETS manual). One way AOV test was used to compare variables among groups and results are shown in Table 1. A significant increase in total CL was observed for the groups receiving 75% or 100% of the recommended dose with respect to the group receiving 50% of that dose. There was also a significant greater number of grade 1 embryos for the groups receiving 75% or 100% of the dose than in the group receiving 50% of the recommended dose. There were no differences for any of the evaluated parameters between 75% and 100% dose groups. These results suggest that acceptable superstimulatory responses can be obtained using reduced doses of Ovagen® in Aberdeen Angus donor cows. (*) the percentage makes reference to the total dose recommended by the laboratory of origin. Table 1.Embryo collection results of superstimulated donors with different dose* of NIADDK-oFSH-Z (Ovagen) Research supported by Syntex S.A. and Eolia S.A.

295 SUPEROVULATORY RESPONSE IN COWS FOLLOWING SYNCHRONIZATION OF FOLLICLE WAVE EMERGENCE WITH ESTRADIOL AT DIFFERENT STAGES OF THE ESTROUS CYCLE

Ovarian asynchrony and variability in response to superstimulation remain the most limiting factors in any embryo transfer program (Armstrong D 1993 Theriogenology 39, 7–24). Ovarian response can be increased and less variable if superstimulatory treatment is started at the time of follicular wave emergence (Bö GA et al. 1995 Theriogenology 43, 31–40). A combination of progesterone (P4) and estradiol have been used to synchronize follicular wave for superstimulation. A retrospective analysis was done to compare the ovarian response, superovulatory response and embryo production of cows in Argentina that received progesterone and estradol prior to superstimulation at different stages of the estrous cycle. This research was carried out using different breed of donors (n = 584, 88% Angus) during the last 4 years in Buenos Aires province, Argentina. Heat detection was performed twice a day. At random stages of the estrous cycle, donors received an intravaginal progesterone device (DIB; Syntex, Buenos Aires, Argentina), 2 mg of estradiol benzoate and 50 mg of progesterone (Syntex, Buenos Aires, Argentina) IM on the same day. On day 4 after DIB insertion, superestimulatory treatment was initiated on a decreasing dose regimen of FSH (Pluset; Callier, Spain, or Folltropin, Bioniche Animal Health Inc., Belleville, Ontario, Canada) as IM injections every 12 h over 4 d. On day 6, DIBs were removed, and cows received two doses of 2 mL of cloprostenol 12 h apart. At heat detection, all donors received a dose of 2 mL of GnRH (Dalmarelin; Fatro Von Franken, Buenos Aires, Argentina) by IM injection and were inseminated 12 and 24 h later. Seven days later, embryo collection was performed and ovarian response was evaluated as number of CL + unovulated follicles by transrectal ultrasound using a 7.5-MHz transducer (Pie Medical, Maastricht, the Netherlands). Ova/embryos were evaluated and classified according to the IETS manual. Donors were assigned to receive DIB and estradiol during the following stages of the cycle: group 1: between days 4 and 7 post-estrus (dominant follicle period), group 2: between days 8 and 12 post-estrus (emergence of the second follicular wave), and group 3: between days 13 and 21 post-estrus (dominant follicle of the second wave). Kruskal-Wallis test was used to compare variables among groups, and results are shown in Table 1. Ovarian response as CL + unovulated follicles and number of ovulations were significantly different among groups (P < 0.05). However, there was no significant difference in the number of fertilized ova or transferable embryos. Nevertheless, numeric differences that show that group 2 (started between days 8 and 12 post-estrus) was always superior for all variables. In conclusion, data suggest that estradiol may be more effective in synchronizing follicle wave emergence for superstimulation during the mid-part of the estrous cycle. Table 1. Superovulatory response in cows in which follicle wave emergence was synchronized with estradiol at different stages of the estrous cycle (mean ± SD) Research supported by Centro Genetico Bovino Eolia S.A.

151 EFFECT OF RECIPIENT CATEGORY ON PREGNANCY RATES ON A BOVINE EMBRYO TRANSFER PROGRAM IN PATAGONIA, ARGENTINA

The fertility of the recipient is one of the more important factors conditioning the success of an embryo transfer (ET) program. Selection and management of recipients is a very important contributing factor to achieve high pregnancy rates (Stroud and Hasler 2006 Theriogenology 65, 65–76). From a reproductive point of view, a good recipient is a cow capable of receiving an embryo and taking it to term (Palma et al. 2001 Biotecnologia de la reproduccion, INTA). In beef and dairy cattle, recipients are categorized according to number of births, age, and condition score (Stroud and Hasler 2006). A retrospective analysis was done to confirm a relationship between recipient category, based on their physiologic and reproductive stage, and pregnancy rates. The analysis was done during January and February (2006–2007) based on data recovered from an embryo transfer program done in Chubut province (Patagonia) for the project ‘Polo Genetico Angus’ (Angus Association – Chubut government agreement). Two hundred and seven morulas and/or blastocysts, quality 1 or 2 frozen in 1.5 m ethylene glycol (IETS manual), were transferred randomly in 10 different farms. Embryos were thawed for 10 s at room temperature and 30 s in a water bath at 35°C and transferred by one single technician. Angus, Hereford, or its breeds were used as recipients. A reproductive exam was performed before embryo transfer and, based on it, recipients were classified into 4 categories: heifer (3–4 years old), lactating cow, weaned cow, and dry old cow (Table 1). The synchronization protocol used for recipients consisted of a single administration of D-cloprostenol and heat detection twice a day for 5 days. Data were analyzed by Cochran-Mantel-Haenszel test (chi-square). Results are shown in Table 1. There is a significant difference (P ≤ 0.05) in pregnancy rates among categories. Recipients with higher pregnancy rates were lactating cows and weaned cows 61.6% and 56.9%, respectively, compared to heifers, 45.3%; a lower pregnancy rate was founded in the dry old cows group. Dry cows were animals that failed to get pregnant during the last season. Heifers also were animals that failed the artificial insemination program. In both groups, the reduced fertility may explain their lower pregnancy rates. In conclusion, selection toward fertility of recipients is a very important factor to take into account to design a successful embryo transfer program. Table 1. Pregnancy rates for recipient categories in an ET program in Chubut (Patagonia), Argentina This research was supported by Centro Genetico Bovino Eolia.

Colonic diversion for intractable constipation in children: colonic manometry helps guide clinical decisions

BACKGROUND

Colonic manometry helps discriminate functional and behavioral causes for childhood constipation from colonic neuromuscular disease.

METHODS

Of 375 colonic manometries performed for clinical indications, 12 could not be interpreted because of chronic colonic dilation. Based on colonic manometries that showed either no contractions or an absence of the gastrocolonic response or an absence of high-amplitude propagating contractions, the authors recommended diverting colostomies or ileostomies in 12 chronically constipated children (mean age, 4 years; range, 2-14 years, 5 boys). Before study, medical treatment was ineffective in all children. These children had persistently dilated colons with pathologic diagnoses of intestinal neuronal dysplasia (n = 4), hypoganglionosis (n = 2), hollow visceral myopathy (n = 1), and normal (n = 5).

RESULTS

Six to 30 months after diversion, the authors restudied all the children. Eleven of 12 diverted colons were no longer dilated. In two patients, abnormal motility involving the entire colon was unchanged from the initial study, small bowel motility was abnormal, and we recommended no further surgery. In two cases, the colon remained abnormal but small bowel motility was normal, and we recommended subtotal colectomy and ileoproctostomy. In four cases, the left colon remained abnormal, but the right colon was normal, and we recommended reanastomosis after left hemicolectomy. In four cases, motility in the diverted colons was normal, including a gastrocolonic response and high-amplitude propagating contractions, and the authors recommended reanastomosis. Defecation problems resolved in 10 of 12 when followed up 5 to 30 months after treatment.

CONCLUSION

These data suggest that in some cases of intractable childhood constipation associated with colonic distention, temporary diversion improved colonic motility. Colonic manometry may be used to predict which patients will benefit from resection or reanastomosis.

Antiphosphatidylethanolamine antibodies contribute to the diagnosis of antiphospholipid syndrome in patients with systemic lupus erythematosus

OBJECTIVE

To evaluate the correlation between antiphosphatidylethanolamine antibodies (aPE) and some antiphospholipid antibodies (aPL)-related clinical manifestations in patients with systemic lupus erythematosus (SLE).

METHODS

Patients with SLE (n=217) were tested for the presence of aPE, anticardiolipin antibodies (aCL), and lupus anticoagulant (LA). The prospective aPL-related clinical manifestations studied were: thrombosis, thrombocytopenia, recurrent fetal losses, heart valvulopathies, hemolytic anemia, livedo reticularis, and pulmonary hypertension.

RESULTS

A total of 109 SLE patients (50.23%) were IgG aPE-positive; 17.51% presented aPE as the sole autoantibody and had some clinical features of aPL-related clinical manifestations. IgG aPE were associated to the presence of heart valvulopathies (p=0.002). A statistical difference was also found when considering high levels of IgG aPE (O.D.>0.600) in patients with livedo reticularis (p=0.008).

CONCLUSION

The evaluation of IgG aPE may allow us to detect some more patients with aPL-related clinical manifestations in the SLE population, aPE correlated particularly with valvulopathies and livedo reticularis.

Mannose binding lectin and FcgammaRIIa (CD32) polymorphism in Spanish systemic lupus erythematosus patients

OBJECTIVE

Mannose binding lectin (MBL) and FcgammaRII (CD32) polymorphisms have both been implicated as candidate susceptibility genes in systemic lupus erythematosus (SLE). The aim of this study was to evaluate the relationship of these polymorphisms with SLE.

METHODS

We studied a cohort of 125 SLE patients from Barcelona, Spain and 138 geographically matched controls. Sequence-specific primer-polymerase chain reaction (SSP-PCR) amplification was used to determine CD32 and MBL structural polymorphisms. MBL haplotypes were established using sequence-specific oligonucleotide probing techniques.

RESULTS

Patients carried the MBL codon 54 mutant allele more frequently than controls [odds ratio (OR) 2.2; 95% confidence interval (CI) 1.2-4.0; P=0.007] and the haplotype HY W52 W54 W57 was found to be significantly lower in cases compared with controls (OR 0.6; 95% CI 0.4-0.9; P=0.016).

CONCLUSION

The MBL gene codon 54 mutant allele appears to be a risk factor for SLE, whilst haplotypes encoding for high levels of MBL are protective against the disease. Differences between controls and patients were not significant when considering the FcgammaRIIa polymorphisms; similar results were observed for renal affectation.

Anticardiolipin antibodies in patients with chronic hepatitis C virus infection: characterization in relation to antiphospholipid syndrome

The antiphospholipid syndrome (APS) is usually defined by the association of clinical manifestations that comprise venous and/or arterial thrombosis, recurrent fetal losses, and thrombocytopenia, along with the presence of anticardiolipin (aCL) antibodies and/or lupus anticoagulant. Various infectious diseases can induce aCL; however, these antibodies are not usually associated with thrombotic events, as happens with autoimmune diseases, in which these antibodies need the presence of beta(2)-glycoprotein I. Levels of immunoglobulin G (IgG) and IgM aCL antibodies were determined by enzyme-linked immunosorbent assay for 243 patients with chronic hepatitis C virus (HCV) infection and 100 healthy controls. Clinical events of APS, the level of beta(2)-glycoprotein dependence of aCL, the presence of cryoglobulins and other autoantibodies, and cross-reactivity between purified aCL and HCV were evaluated. Positive results for aCL antibodies were found more frequently (3. 3%) for the patients with HCV infection than for healthy controls (0%). All positive aCL antibodies were beta(2)-glycoprotein I independent. No significant association was found between aCL antibodies and clinical manifestations of APS, neither was one found between the presence of other autoantibodies or cryoglobulins and that of aCL. Finally, no cross-reactivity between aCL antibodies and HCV antigens was observed. As previously reported, aCL antibodies seem to be an epiphenomenon, and they do not have clinical or laboratory significance in HCV patients.

Tumor necrosis factor receptor II (TNFRII) exon 6 polymorphism in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a complex autoimmune disease that exhibits extensive clinical heterogeneity. Several studies have suggested a role for tumor necrosis factor alpha (TNFalpha) in SLE and recently, the locus encompassing the TNF receptor II (TNFRII), which is a mediator of TNF effect, was amongst the candidate loci suggested by genetic linkage studies of multi-case SLE families. Komata et al. reported an association between a polymorphism at position 196 (R allele) of TNFR II and SLE in Japanese patients. We have typed SLE patients from two different ethnic populations, Spanish and UK Caucasoids, for this polymorphism using a polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP)-based technique. No significant differences in allele or genotype frequencies were found between cases and matched controls in either population. The TNFRII 196R allele does not appear to be associated with SLE susceptibility in either Spanish or UK populations.

Yeast ribosomal protein L26 is located at the ribosomal subunit interface as determined by chemical cross-linking

Previous studies suggested that yeast ribosomal protein L26 was a candidate for the ribosomal subunit interface region. The present study used protein-protein cross-linking to identify neighboring proteins in intact 80S ribosomes of Saccharomyces cerevisiae. To facilitate identification of cross-linked pairs involving L26, 80S ribosomes were first treated with 5-iodoacetamidofluorescein to selectively label L26. Protein cross-links were produced with dithiobis[succinimidyl] propionate or N-succinimidyl-3-[2-pyridyldithio] propionate and analyzed by electrophoresis on two-dimensional diagonal polyacrylamide gels containing SDS. L26 was detected under UV and its cross-linked partner, detectable after staining with Coomassie blue, was located below the diagonal and was coincident with L26 on a single vertical axis. The identity of the partner was determined by its co-migration with 60S and 40S ribosomal protein markers on two-dimensional gels. Two protein pairs involving L26 and 40S subunit proteins were identified. The finding provided experimental evidence to support that L26 is located at the ribosomal subunit interface. A model that incorporates the present findings and the published data on intra-subunit protein pairs is proposed for the yeast 80S ribosome.

Cerebral cysticercotic arteritis: detection and follow-up by transcranial Doppler

Intracranial arteritis is a well-known complication of cerebral cysticercosis. The aim of this study was to explore the possible role of transcranial Doppler (TCD) in the evaluation of cysticercotic arteritis in 9 patients with subarachnoid cysticercosis and stroke. Arteritis of main basal vessels was detected by TCD in 7 of 10 arterial lesions that were demonstrated by cerebral angiography. The Doppler pattern was occlusive in 2 cases and stenotic in 5. In the 3 patients with lacunar infarcts, both cerebral angiography and TCD were normal. In 6 arterial lesions followed serially with TCD a stenotic pattern resolved within 4 and 6 months in 3 cases and remained in the stenotic range at 12 months in 1 case, whereas an occlusive pattern persisted at 6 and 18 months in the other 2 cases. In conclusion, TCD may be useful to detect and follow up cerebral vasculitis due to chronic cysticercotic arachnoiditis.

Bioimpedance monitoring of rehydration in cholera

Measurement of bioimpedance (BI) is a simple non-invasive technique that relies on the different conductivity of tissues to define body composition and can be easily adapted to automated monitoring. We assessed the accuracy of BI in monitoring rehydration and acute fluid fluxes in 35 Peruvian cholera patients. Patients were monitored throughout the acute phase of diarrhoea and followed up at 3 and 10 days. BI was compared with other objective measures of dehydration including packed cell volume, serum protein, and calculated fluid balance. BI rapidly detected inadequate treatment and acute fluid flux, correlating highly with intravascular hydration as measured by serum protein and packed cell volume. BI values during dehydration were significantly raised compared with 10-day convalescent values and age-matched controls (p < 0.05). We also encountered an unexpected difference in the bioelectrical response to dehydration and rehydration between sexes. We conclude that BI has uses in monitoring dehydrated patients, in oral rehydration trials, and in physiological studies.

[Treatment of diarrheic disease at home. Comparison of 2 forms of oral solutions: liquid and concentrated in small bags]

One hundred children, ranging in ages from a month to a year, with acute diarrhea who were treated at home following the basic standard recommendations, were studied. In order to prevent dehydration, half of the children were given oral solution (OS) containing the concentrated official formula in packets (group A), and the remaining half was given a commercially prepared ready-to-use OS (group B). During the treatment period, two house calls were made and the third day the patient was asked to come in for a check-up at the hospital. The clinical and socioeconomic characteristics were similar in both groups. The majority of parents made some reference to the "salty" taste of their OS, while only a few thought it has a sweet taste. In Group B, there were greater numbers of relatives who did not wash their hands before administering the OS and did it through bottles. A reminder was given on suggestive signs of dehydration expected, during the second home visit, although they were few. In both groups the average amount of OS administered was greater than 40 mL/kg/24 hours. The majority of the patients gained weight during the treatment. Four patients showed signs of slight dehydration (three from group A and one from group B). The OS's bacteriologic examination was positive for enteropathogens in 16% of the samples from group A and in 5% from group B. The average time the diarrhea continued was similar for both groups. Sodium concentration ranged from 60 to 120, potassium from 15 to 30 mmol/L, in 85% of those cases in group A and 98% in group B.(ABSTRACT TRUNCATED AT 250 WORDS)

Influence of previous housing history on the toxicity of amphetamine in aggregate mice

The lethality of d-amphetamine was studied in isolated and aggregated mice with and without previous habituation to the physical or to the physical and social environment of chronically aggregated social condition under which the toxic effects of d-amphetamine were tested. In animals without previous habituation to such environments, d-amphetamine's toxicity was greatly enhanced by social aggregation, as reported by several authors in the literature. It was found that mortality in the dose range from 5 to 90 mg/kg is mainly determined by the stimulation due to aggregation. Above 90 mg/kg, the mortalities in single and aggregated mice vary in parallel. Up from this dose, lethality is independent of the external stimulation. Previous experience with house sharing in aggregated conditions reduces aggregation mortality in proportion to the duration of the previous house sharing period.

Isolation and sequence analysis of a somatostatin-like polypeptide from ovine hypothalamus

A large somatostatin-like polypeptide of apparent molecular weight 3000-4500 [4K somatostatin (SS)] was isolated from ovine hypothalamus. The polypeptide was obtained in the methionine sulfoxide form. Two microsequence analyses of 0.6 and 1.8 nmol of 4K SS were performed with a modified 890 C spinning cup sequencer. The sequencing data together with results of amino acid analysis and C-terminal end-group determination indicated that 4K SS was identical with somatostatin-28 (SS-28) isolated from procine upper small intestine and sequenced by Pradayrol et al. [Pradayrol, L., Jörnvall, H., Mutt, V., & Ribet, A. (1980) FEBS Lett. 109, 55-58]. No free cysteine sulfhydryl group could be detected, so that it was assumed that the two cysteine residues of ovine SS-28 formed an intramolecular disulfide bond. Besides the structure of SS-28, the N-terminal first 30 residues of an unknown polypeptide from ovine hypothalamus were sequenced as follows: H-Ile-Pro-Ile-Tyr-Glu-Lys-Lys-Tyr-Gly-Gln-Val-Pro-Met-Cys-Asp-Ala-Gly-Glu-Gln- Cys-Ala-Val-Arg-Lys-Gly-Ala-Arg-Ile-Gly-Lys. Trypsin cleaved the somatostatin (SS) entity less selectively from ovine hypothalamic SS-28 than from rat hypothalamic 12 000-dalton SS-like polypeptide (12K SS). Native ovine hypothalamic SS-28 was found to be highly potent in inhibit growth hormone release from cultured rat anterior pituitary cells. The results raised doubts that ovine SS-28 would be an SS precursor and indicated that SS-28 itself may possess regulatory functions.