Etiologies of Mild and Moderate Diarrheal Illness among Children in Consuelo, Dominican Republic

Since the rotavirus vaccine was included in the Dominican Republic's national immunization schedule in 2012, the microbiologic etiologies of acute gastroenteritis have not been described. This study aimed to determine the contribution of rotavirus as an etiology of acute gastroenteritis over a 12-month period in children under 5 years of age in both an inpatient and an outpatient setting in Consuelo, Dominican Republic. All children who were seen at Niños Primeros en Salud clinic or admitted to Hospital Municipal Dr. Angel Ponce Pinedo for acute gastroenteritis during January 2021-April 2022 were enrolled in the study. Stools were evaluated for rotavirus, enteric parasites, and pathogenic bacteria. Pathogen detection was compared between outpatients and inpatients and on the basis of child's vaccination status. From 181 children enrolled, 170 stool samples were collected, 28 (16.5%) from inpatients and 142 (83.5%) from outpatients. Rotavirus was the most commonly detected pathogen and was proportionately more common among hospitalized children, with nine (32.1%) cases among hospitalized children and 16 (11.3%) among outpatient children. (Pearson χ2 = 8.1, P = 0.004). Among patients with a positive rotavirus result, vaccination rate was lower among moderate (hospitalized) (three of six; 50%) compared with mild (outpatient) diarrhea patients (12 of 15; 80%). Giardia lamblia (10%) was the next most prevalent pathogen detected in both inpatients and outpatients using standard laboratory measures. Despite the availability of rotavirus vaccination, rotavirus remains a common cause of gastrointestinal illness among children under 5 years of age in our cohort. Incomplete vaccination status was associated with hospitalization for gastrointestinal illness.

Near-term pregnant women in the Dominican Republic experience high rates of Group B Streptococcus rectovaginal colonization with virulent strains

Maternal colonization with Group B Streptococcus (GBS) is an important cause of stillbirth, prematurity, and serious infection and death in infants worldwide. Resource constraints limit prevention strategies in many regions. Maternal GBS vaccines in development could be a more accessible prevention strategy, but data on geographic variations in GBS clones are needed to guide development of a broadly effective vaccine. In the Dominican Republic (DR), limited data suggest that pregnant women experience GBS colonization at rates among the highest globally. We aimed to determine the prevalence of maternal rectovaginal GBS colonization and describe clonal characteristics of colonizing strains in the DR. A cross-sectional study assessed rectovaginal GBS colonization in 350 near-term pregnant women presenting for routine prenatal care at an urban tertiary center in the DR. Rectovaginal samples were tested with chromogenic Strep B Carrot Broth and cultured for confirmatory whole-genome sequencing. In a secondary analysis, participants' demographics and histories were assessed for association with GBS colonization. Rectovaginal GBS colonization occurred in 26.6% of women. Serotypes Ia, Ib, II, III, IV, and V were detected, with no one serotype predominating; serotype III was identified most frequently (21.5%). Virulent and emerging strains were common, including CC17 (15.1%) and ST1010 (17.2%). In this first characterization of maternal GBS serotypes in the DR, we found high rates of rectovaginal colonization including with virulent and emerging GBS strains. The serotypes observed here are all targeted by candidate hexavalent GBS vaccines, suggesting effective protection in the DR.

Trocar shortening for pediatric vitreoretinal surgery with a 3D printed trocar spacer: Report of two cases

PURPOSE

To show the results of a trocar spacer for pediatric vitreoretinal surgery with a 3D printed trocar spacer in 2 cases.

METHODS

We used standard 27 gauge (ga) and 25 ga trocars and cannulae, and prototyped 1.5 mm × 3 mm spacers with a Prusa MK3 3D printer (0.4 mm nozzle) with Fuse deposition melting (FDM) technology. Parts were printed with a 50 μm layer height in polylactic acid or polylactide (PLA). The spacer was placed in two places: between the blade's base and the trocar, and between the trocar and the sclera depending on the desired amount of shortening. This prototype was used in 2 vitrectomy cases in pediatric patients.

RESULTS

We used this trocar spacer in 2 cases with positive results.

CONCLUSIONS

This 3D printed spacer has proved to effectively shorten the introduced trocar into two different small eyes. More studies are needed to validate the efficacy and safety of this spacer in clinical practice.

Prebiotics and phytogenics functional additives in low fish meal and fish oil based diets for European sea bass (Dicentrarchus labrax): Effects on stress and immune responses

The use of terrestrial raw materials to replace fish meal (FM) and fish oil (FO) in marine fish diets may affect fish growth performance and health. In the last years functional additives have been profiled as good candidates to reduce the effects on health and disease resistance derived from this replacement, via reinforcement of the fish immune system. In the present study, three isoenergetic and isonitrogenous diets with low FM and FO (10% and 6% respectively) were tested based on supplementation either with 0.5% galactomannanoligosaccharides (GMOS diet) or 0.02% of a mixture of essential oils (PHYTO diet), a non-supplemented diet was defined as a control diet. Fish were fed the experimental diets in triplicate for 9 weeks and then they were subjected to a stress by confinement as a single challenge (C treatment) or combined with an experimental intestinal infection with Vibrio anguillarum (CI treatment). Along the challenge test, selected stress and immunological parameters were evaluated at 2, 24 and 168h after C or CI challenges. As stress indicators, circulating plasma cortisol and glucose concentrations were analyzed as well as the relative gene expression of cyp11b hydroxylase, hypoxia inducible factor, steroidogenic acute regulatory protein, heat shock protein 70 and heat shock protein 90 (cyp11b, hif-1α, StAR, hsp70 and hsp90). As immune markers, serum and skin mucus lysozyme, bactericidal and peroxidase activities were measured, as well as gene expression of Caspase-3 (casp-3) and interleukin 1β (il-1ß). The use of functional additives induced a significant (p < 0.05) reduction of circulating plasma cortisol concentration when confinement was the unique challenge test applied. Supplementation of PHYTO induced a down-regulation of cyp11b, hif-1α, casp-3 and il-1β gene expression 2h after stress test, whereas StAR expression was significantly (p < 0.05) up-regulated. However, when combination of confinement stress and infection was applied (CI treatment), the use of PHYTO significantly (p < 0.05) down-regulated StAR and casp-3 gene expression 2h after challenge test, denoting that PHYTO diet reinforced fish capacity of stress response via protection of head kidney leucocytes from stress-related apoptotic processes, with lower caspase-3 gene expression and a higher il-1β gene expression when an infection occurs. Additionally, dietary supplementation with GMOS and PHYTO compounds increased fish serum lysozyme after infection. Both functional additives entailed a better capability of the animals to cope with infection in European sea bass when fed low FM and FO diets.

Supplementation of arachidonic acid rich oil in European sea bass juveniles (Dicentrarchus labrax) diets: Effects on leucocytes and plasma fatty acid profiles, selected immune parameters and circulating prostaglandins levels

The main objective of this study was to assess the effects of graded levels of dietary arachidonic acid (ARA), supplemented from alternative sources, on fatty acid composition of plasma and head kidney leucocytes of European sea bass (Dicentrarchus labrax). For that purpose, sea bass juveniles were fed four diets containing graded levels of ARA as follows: 0.5% (ARA0.5), 1% (ARA1), 2% (ARA2) and 4% (ARA4) during 60 days. At the end of the feeding trial fatty acid profiles of plasma and head kidney leucocytes were analyzed. Besides, plasma prostaglandins levels, head kidney leucocytes respiratory burst activity; peroxidase activity and phagocytic index were assayed. Reducing dietary ARA levels below 1% markedly reduced European sea bass growth performance. However, fish fed diet ARA0.5 tried to compensate this dietary ARA deficiency by a selective deposition of ARA on plasma and head kidney leucocytes, reaching similar levels to those fish fed diet ARA1 after 60 days of feeding. Nevertheless, head kidney phagocytic capacity was reduced as dietary ARA content in relation not only to variations on membrane composition but also to changes on fish basal prostaglandins levels. Results obtained demonstrated the importance to supply the necessary quantity n-6 LC-PUFA, and not only n-3 LC-PUFA levels, in European sea bass diets, in relation to not only growth performance but also immune system function.

Impact of Preemptive Fibrinogen Concentrate on Transfusion Requirements in Liver Transplantation: A Multicenter, Randomized, Double-Blind, Placebo-Controlled Trial

We hypothesized that preemptive fibrinogen administration to obtain an initial plasma level of 2.9 g/L would reduce transfusion requirements in liver transplantation. A randomized, multicenter, hemoglobin-stratified, double-blind, fibrinogen-versus-saline-controlled trial was conducted. The primary end point was the percentage of patients requiring red blood cells. We evaluated 51 patients allocated to fibrinogen and 48 allocated to saline; the primary end point was assessed using data for 92 patients because the electronic record forms were offline for three patients in the fibrinogen group and four in the saline group. We injected a median of 3.54 g fibrinogen preemptively in the fibrinogen group. Nine patients in the saline group (20.9%) required fibrinogen at graft reperfusion (compared with one patient [2.1%] in the fibrinogen group; p = 0.005). Blood was transfused to 52.9% (95% confidence interval [CI] 42.5-63.3%) in the fibrinogen group and 42.74% (95% CI 28.3-57.2%) in the saline group (p = 0.217). Relative risk for blood transfusion was 0.80 (95% CI 0.57-1.13). Thrombotic events occurred in one patient (2.1%) and five patients (11.4%) in the fibrinogen and saline groups, respectively. Seven patients (14.6%) in the fibrinogen group and nine (20.3%) in the saline group required reoperation. Preemptive administration of fibrinogen concentrate did not influence transfusion requirements.

Variances in the Use of Everolimus in Kidney Transplantation: A 2-Year Registry of Everyday Practice

BACKGROUND

Everolimus (EVL)-based immunosuppressive strategies may permit the reduction of calcineurin inhibitors (CNI) and their side effects, while offering a safe and efficient treatment. Our aim was to describe our experience with EVL in everyday practice and provide information for its optimal utilization.

METHODS

Prospective, multicenter study of 181 kidney transplant recipients treated with EVL as part of their immunosuppressive regimen, with a follow-up of 24 months. We studied demographic data, transplant characteristics, clinical information, drugs used, serum creatinine, estimated glomerular filtration rate (eGFR), rejection episodes, and adverse events.

RESULTS

In total, 181 renal transplant recipients were included. Of these, 30 (16.6%) received EVL de novo and 151 (83.4%) were converted; median time from transplantation to conversion was 10 (range, 1-312) months. Main reasons for conversion were prevention of interstitial fibrosis and tubular atrophy (23.9%), intolerance to immunosuppressants (11.1%), neoplasia (13.9%), nephrotoxicity (8.9%), and cytomegalovirus infections (8.3%). The eGFR values at baseline, months 12, and 24 were 46.4 ± 27.4 mL/min, 54.8 ± 22.9 mL/min, and 55.9 ± 26.5 ml/min, respectively. Two of 181 (1.1%) patients died, 5 of 181 (2.8%) lost their grafts, 12 of 181 (6.6%) had an episode of acute rejection, 13 of 181 (7.2%) had ≥1 serious event and infection, and 85 of 181 (49.9%) had ≥1 nonserious adverse event or infection. Multivariate analysis showed that increased eGFR at month 24 was associated with lower donor age, shorter time from transplant to EVL introduction, and a baseline eGFR ≥40 mL/min.

CONCLUSION

Through different strategies among centers, the inclusion of EVL improved renal function during the first 12 months.

Differential innate immune response of European seabass (Dicentrarchus labrax) against Streptococcus iniae

Streptococcus iniae is a Gram-positive bacteria that causes invasive infections with severe septicemia and meningitis, producing high economic losses in marine and continental aquaculture. Head kidney leukocytes of European sea bass (Dicentrarchus labrax) were used to measure the differential innate immune response upon infection with S. iniae. The complete inhibition in the production of intracellular superoxide radicals and total peroxidase content was observed in infected cells. This study also elucidates changes in the relative expression of some immune-related genes. Interleukin 1β, tumor necrosis factor-α and interleukin-6 reached a peak of expression at 4-8 h post-infection, subsequently decreasing significantly up to 48 h post-infection. However, interleukin-10 and Mx protein increased over time, reaching the pick of expression at 48 h post-infection, whereas caspase-3 showed down regulation until 48 h post-infection. The in vivo study of immune related genes show the same kinetics of mRNAs expression as in vitro experience. The proinflammatory cytokines mRNA transcription levels peaked at an earlier time in vivo than in vitro system. Our findings indicate that there is a direct relationship between the dissemination of bacteria and the resulting infection-associated inhibition of respiratory burst, apoptosis, and the pro- and anti-inflammatory gene expression profiles.

Immunization of sea bream (Sparus aurata) juveniles against Photobacterium damselae subsp. piscicida by short bath: Effect on some pro-inflammatory molecules and the Mx gene expression

Cytokines are a family of proteins derived from macrophages, lymphocytes, granulocytes, mast cells and epithelial cells and can be divided into interferons (IFNs), Interleukins (ILs) and Tumor Necrosis factors (TNFs) among others. The presence of cytokines in a wide number of fish species has been proved and several molecules types have been already cloned and sequenced. In this work some proinflamatory molecules and Mx gene were detected in the liver of vaccinated sea bream juveniles with an average body weight of 5 g. The method of immunization was by short bath and three different bacterins against the marine pathogen Photobacterium damselae subsp. piscicida were designed and used to immunize fish. Five genes encoding for five different molecules were analyzed by real time PCR: IL-1β, IL Ir-2, Cox-2, Mx and TNFα. Gene expression was quantified along four days after fish immunization and results were compared among groups. Results show that the heat-inactivated vaccine stimulates the up-regulation of IL-1β, IL Ir-2, Cox-2 and TNFα genes whereas the UV-light inactivated vaccine was the unique vaccine which stimulates the expression of Mx gene. The present is a novel study that shows by the first time the effect of the inactivation process of vaccines on the expression levels of genes involved in the defense against Photobacterium damselae subsp piscicida.

The in vitro immunomodulatory effect of extracellular products (ECPs) of Vagococcus fluvialis L21 on European sea bass (Dicentrarchus labrax) leucocytes

The immune associated genes, interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin 10 (IL-10), tumor necrosis factor-α (TNF-α), ciclo-oxigenase-2 (COX-2), and Mx gene were studied by real-time PCR in head-kidney leucocytes of sea bass after incubation with the extracellular products (ECPs) of the probiotic strain Vagococcus fluvialis L21 and polyinosinic:polycytidylic acid (POLY I:C), at different times (T1.5, T6, T12, T24, T48 and T72). In general, we can observe how pro-inflammatory cytokines IL-1β, TNF-α, IL-6 and COX-2 studied displayed a strong peak after stimulation with 1.5 h of ECPs of V. fluvialis L21, significant differences (P < 0.05) exist with other periods and with the POLY I: C at the same time. Similarly to the case of IL-10 also produced a statistically significant (P < 0.05) peak of expression on leukocytes that were stimulated with the ECPs of V. fluvialis L21. In the case of Mx gene expression, we note that in almost all sampling times there is an up-regulation of the Mx gene in leucocytes incubated with ECPs and POLY I:C compared to the control and Mx expression was higher in leucocytes that were stimulated with the ECPs of V. fluvialis for all times, except in T24. With these results we can consider that the ECPs of V. fluvialis L21 have a great power of stimulating the in vitro expression of immune-related genes and may even be useful as adjuvants for vaccine in aquaculture.

Streptococcus iniae in gilthead seabream (Sparus aurata, L.) and red porgy (Pagrus pagrus, L.): ultrastructural analysis

Streptococcosis caused by Streptococcus iniae has become one of the most serious marine and freshwater aquatic diseases in the past decade, causing large losses in farmed and wild fish worldwide. In this study, we performed an ultrastructural study of major lesions in gilthead seabream Sparus aurata and red porgy Pagrus pagrus experimentally infected with the S. iniae IUSA-1 strain, isolated in a natural outbreak in Spain in the mentioned species. The transmission electron micrographs revealed the resistance of this pathogen inside the phagosome, indicating that the macrophage may provide a significant bacterial reservoir for continuing infection, disease dissemination, and tissue injury by crossing the blood-brain barrier.

Efficacy of Ceftaroline Fosamil against Escherichia coli and Klebsiella pneumoniae strains in a rabbit meningitis model

In this study, the efficacy of ceftaroline fosamil was compared with that of cefepime in an experimental rabbit meningitis model against two Gram-negative strains (Escherichia coli QK-9 and Klebsiella pneumoniae 1173687). The penetration of ceftaroline into inflamed and uninflamed meninges was also investigated. Both regimens were bactericidal, but ceftaroline fosamil was significantly superior to cefepime against K. pneumoniae and E. coli in this experimental rabbit meningitis model (P < 0.0007 against K. pneumoniae and P < 0.0016 against E. coli). The penetration of ceftaroline was approximately 15% into inflamed meninges and approximately 3% into uninflamed meninges.

Cytokine expression in head-kidney leucocytes of European sea bass (Dicentrarchus labrax L.) after incubation with the probiotic Vagococcus fluvialis L-21

The European sea bass (Dicentrarchus labrax L.) is one of the most extensively farmed marine fish in the Mediterranean sea. Under the high-density condition, common in aquaculture, the infectious diseases can cause significant economic losses. Probiotics are presented as an alternative to antibiotics for the control of aquaculture diseases. This study used real-time PCR to investigate in vitro the dynamic of expression of immune-related genes in sea bass after incubation with live and inactivated (heat and Uv-light) probiotic Vagoccus fluvialis L-21 at different times (T1, T12, T24, T48). The immune associated genes, interleukin-1 (IL-1), interleukin-6 (IL-6), interleukin 10 (IL-10), TumourTumour necrosis factor- (TNF-), ciclo-oxigenase-2 (COX-2), caspase-3 (Casp-3) and Mx were studied in head-kidney (HK) leucocytes of sea bass after incubation with the probiotic strain. Transcript of proinflammatory cytokines (IL-1, TNF-, COX-2) was highly up-regulated after 1 h of incubation with the probiotic strain V. fluvialis L-21. We found statistically significant difference in pick of expression of TNF-, after 1 h of incubation with Uv-light inactivated probiotic strain. The COX-2 expression was highly up-regulated at all times studied, with the exception of 12 and 24 h post incubation for the Uv-light inactivated bacteria. Transcript of IL-10 and Casp-3 showed the higher statistically significant differences of expression after 48 h post incubation with live bacteria. In the contrast, sea bass HK leucocytes expressed Mx at 12 and 48 h without statistically differences among treatments. Our results suggest that V. fluvialis L-21 is able to stimulate in vitro some immune-related genes associated with the early inflammatory response. Future studies in vivo are necessary to clarify this process in sea bass.

Efficacy of ceftaroline fosamil against penicillin-sensitive and -resistant streptococcus pneumoniae in an experimental rabbit meningitis model

Ceftaroline is a new cephalosporin with bactericidal activity against resistant Gram-positive organisms, including methicillin-resistant Staphylococcus aureus (MRSA) and penicillin-resistant Streptococcus pneumoniae, as well as common Gram-negative organisms. This study tested the prodrug, ceftaroline fosamil, against a penicillin-sensitive and a penicillin-resistant strain of S. pneumoniae in an experimental rabbit meningitis model. The penetration of ceftaroline into inflamed meninges was approximately 14%. Ceftaroline fosamil was slightly superior to ceftriaxone against the penicillin-sensitive strain and significantly superior to the combination of ceftriaxone and vancomycin against the penicillin-resistant strain.

Effect of lipopolysaccharides from Vibrio alginolyticus on the Mx gene expression and virus recovery from gilthead sea bream (Sparus aurata L.) experimentally infected with Nodavirus

Infections with nodavirus affect a wild and farmed fish species throughout the world, mostly from the marine environment. The aim of this work was to determine the immune status of gilthead sea bream that comes as a result of a Nodavirus infection, induced by activation of the interferon response pathway by lipopolysaccharides from Vibrio alginolyticus and the expression of interferoninduced Mx protein in liver samples. The enhancement of Mx protein gene expression was detected in liver samples of experimentally nodavirus infected fish and, furthermore, the immunostimulant LPS of V. alginolyticus decreased almost three times the virus titration with respect to no-immunized or infected with nodavirus group of fish.

The in vitro effect of probiotic Vagococcus fluvialis on the innate immune parameters of Sparus aurata and Dicentrarchus labrax

In this study we evaluated the effect of the probiotic Vagococcus fluvialis on the cellular immune unspecific system of two different fish species of great interest in aquaculture such as gilthead sea bream (Sparus aurata) and European sea bass (Dicentrarchus labrax). Leucocytes from head kidney of the two fish species were extracted and concentration adjusted to 10(7) cells ml(-1). Phagocytic and respiratory burst activity and the peroxidase content of leucocytes were observed 30 min after incubation with the probiotic Vagococcus fluvialis alive or inactivated with heat shock or UV-light at different concentrations of 10(7), 10(8), 10(9) cfu ml(-1) (final concentration 10(6), 10(7), 10(8) cfu ml(-1)). V. fluvialis produced dose-dependent increments in respiratory burst in sea bream leucocytes. The respiratory burst activity of sea bream head kidney leucocytes incubated with 10(6) cfu ml(-1) of live and inactivated bacteria was not stimulated. The highest values of peroxidase content were observed in sea bass cells with stimulation indexes higher than 1 in HK leucocytes incubated with 10(8) cfu ml(-1) of live and inactivated bacteria. Statistical analysis revealed that differences being only significant in sea bass leucocytes where 10(8) cfu ml(-1) bacteria denote statistically significant differences (P < 0.05) respect to other concentrations. Highest values of phagocytic activity were obtained in sea bass macrophages incubated with UV-light inactivated bacteria (27.33% ± 1.45), where significantly differences with sea bass HK leucocytes were detected. Our results suggest that the in vitro assays are a useful tool to optimize the effective dose of probiotic bacteria. Although in vivo studies are necessary to confirm the immunomodulatory effect of this strain.

In vitro study of adherence, invasion, and persistence of Streptococcus iniae in fibroblastic-like fish cell line SAF-1

Streptococcus iniae is a major fish pathogen producing invasive infections that result in economic losses in aquaculture. Gentamicin protection assays were used to investigate the ability of different S. iniae strains to invade and adhere to fibroblastic-like fish cell line SAF-1. All strains tested were detected intracellularly using both techniques, with variable internalization degrees between strains. The experiments carried out at 4°C demonstrated that active cell metabolism is necessary for bacterial internalization. Intracellular bacteria were detected for up to 3 d with a round morphology and were stained with 4',6-diamidino-2-phenylindole (DAPI), indicating that some bacterial cells may remain viable inside SAF-1 cells. Our in vitro findings indicate that S. iniae is capable of adhering, entering, and surviving within fibroblastic cells, which may be important for the persistence and establishment of a carrier state.

Interaction of Corynebacterium pseudotuberculosis with ovine cells in vitro

Caseous lymphadenitis is an infectious and contagious disease caused by Corynebacterium pseudotuberculosis, with a worldwide distribution and high prevalence in small ruminant populations. This disease causes significant economic loss in small ruminants through reduced meat, wool, and milk production. C. pseudotuberculosis can also affect horses, domestic and wild large ruminants, swine, and man. It is considered an occupational zoonosis for humans. As part of in vitro investigations of the pathogenesis of C. pseudotuberculosis, this study analyzed its capacity to adhere to and invade the FLK-BLV-044 cell line, derived from ovine embryonic kidney cells. C. pseudotuberculosis showed a measurable capacity to adhere to and invade this cell line with no significant differences between the four strains assessed. The incubation of the cell line at 4ºC, pre-incubation with sugars, complete and heat inactivated antiserum, and heat-killed and ultraviolet-killed bacteria produced a significant (P < 0.05) decrease in the invasion efficiency or inability to invade the cell line. Plate counting and fluorescence studies showed intracellular bacteria for up to 6 days. Non-phagocytic cells may therefore act as a suitable environment for C. pseudotuberculosis survival and play a role in the spread of infection and/or maintenance of a carrier state.

First report of Streptococcus iniae in red porgy (Pagrus pagrus, L.)

This work describes the first isolation of Streptococcus iniae in red porgy, Pagrus pagrus (L.), and the first European isolation of this pathogen in gilthead seabream, Sparus aurata (L.). In both farmed fish species, infection resulted in lethargy, anorexia, abnormal swimming, exophthalmia and sudden death, with mortality rates of over 25% in red porgy and 10% in gilthead seabream. Beta-haemolytic Gram-positive cocci, catalase negative and oxidase negative, were isolated in pure culture from internal organs. Conventional and rapid identification systems, and 16S rRNA gene partial sequencing were used to identify the causative agent of the natural disease. LD50 trials were carried out to show the virulence of this isolated strain in these species, with values of 1.7 × 104 CFU per fish in red porgy and 1.32 × 105 CFU per fish in gilthead seabream. The most prominent lesions were meningoencephalitis and multifocal infiltration of macrophage cells in the kidney and spleen.

[Demographic distribution and prevalence of overactive bladder in Venezuela]

OBJECTIVE

There is a lack of information regarding overactive bladder (OAB) in South America. Our aim in this study was to estimate the prevalence of overactive bladder (OAB) in Venezuela based on the 2002 International Continence Society (ICS) consensus criteria and also to verify its demographic distribution in this country.

SUBJECTS AND METHODS

We performed a multicentric prospective evaluation of patients from 2003 to 2007 in different cities in Venezuela. A number 3.407 adults (M:38%, F:62%) between 18 and 75 years of age (mean age 54 years) completed a physician guided questionnaire (V8) of urinary symptoms, bladder function, diet, general habits and general medical condition. Statistical procedures were carried out using software based on R programming for computational statistics.

RESULTS

The overall prevalence of OAB in Venezuela was determined as 21%. Female were more affected as compared to male (25.6% vs. 13.7% in men, p < 0.005) OAB was detected at early age (18 yrs) maintaining higher prevalence in women (M: 9%, F: 14%). In the studied cohort OAB shows its highest prevalence between the subgroup of 65 to 69 years of age. In all statistical tests the level of significance was defined as p < 0.005, with a confidence interval of 95%.

CONCLUSION

The OAB-V8 questionnaire aids to clearly identify patients with OAB symptoms. The overall prevalence of OAB in Venezuela is 21%. It is present in both genders, predominantly women and can be detected at early age.

Presence of C. albidus, C. laurentii and C. uniguttulatus in crop and droppings of pigeon lofts (Columba livia)

Columba livia is an important reservoir and carrier of Cryptococcus neoformans, Cryptococcus uniguttulatus, Cryptococcus laurentii and Cryptococcus albidus. Upper digestive tract of this species is also known as a habitat for Cryptococcus neoformans. Given the increasing clinical interest of this microorganism, 331 swabs from crop and 174 dropping samples from pigeon lofts in Grand Canary Island have been studied. The obtained results show an extensive presence samples 81 positive (24.47%) of Cryptococcus spp. in analysed crops: 32 (9.66%) for C. neoformans, 24 (7.2%) for C. uniguttulatus, 23 (6.9%) for C. albidus and 2 (0.6%) for C. laurentii. In the same way, Cryptococcus spp was also isolated in 82 (47.13%), dropping samples: C. neoformans in 59 (33.9%), C. uniguttulatus, in 9 (5.17%), C. laurentii in 8 (4.59%) and C. albidus in 6 (3.44%) of the investigated samples, respectively. The cryptococcosis produced by species of cryptococci other than C. neoformans has become more important during the last decade, supporting the study on the role of pigeon in the epidemiology of this disease.

Invasion and survival of Photobacterium damselae subsp. piscicida in non-phagocytic cells of gilthead sea bream, Sparus aurata L

Fluorescence microscopy and gentamicin protection assays were used to investigate the ability of four Photobacterium damselae subsp. pisicida (Phdp) strains to adhere to and to invade the fish epithelial cell line, SAF-1, derived from Sparus aurata. All strains tested were detected intracellularly using both techniques, although internalization levels varied among strains. Treatment with cytochalasin D and experiments carried out at 4 degrees C demonstrated that a functional host cell cytoskeleton and active cell metabolism are necessary for bacterial internalization. Intracellular bacteria were detected for up to 7 days with a round morphology and were stained with DAPI, indicating that some bacterial cells may remain viable inside SAF-1 cells. Our in vitro findings indicate that Phdp are capable of adhering, entering and surviving within the non-phagocytic epithelial cell line SAF-1, which may be important for persistence and establishment of a carrier state in S. aurata.

Temperature influences the expression of fimbriae and flagella in Hafnia alvei strains: an immunofluorescence study

Hafnia alvei, a Gram negative bacillus related to the Enterobacteriaceae family, is considered an opportunistic pathogen of several animal species and humans. In this communication, we describe fimbrial-like structures from different strains of H. alvei that cannot be easily ascribed to any of the previously reported fimbrial types in this species (type I or type III). Polymerase chain reaction (PCR) and immunofluorescence assays were carried out to study fimbriae and flagella in H. alvei strains isolated from different sources. No correlation between the results obtained by PCR and those obtained by phenotypic methods were found, and the antibodies used gave cross or different recognition patterns of the surface structures present in these strains. We report as well that strain and growth temperature influence fimbriation and expression of flagella in human and animal isolates of H. alvei. This study also indicates that the absence of fimbriae have a significant positive influence on the initial adhesion of H. alvei to human epithelial cells.

Invasion and intracellular survival of Hafnia alvei strains in human epithelial cells

AIMS

The aim of this study was to investigate the invasion and intracellular survival of different Hafnia alvei strains in HeLa cells.

METHODS AND RESULTS

We performed different experiments on the bacterial invasion of different strains of H. alvei into the HeLa cell line using gentamicin protection assays and immunofluorescence. We also report the time course of cell internalization and the effects of inhibitors on the invasion of H. alvei. Levels of invasion varied depending on the conditions (strain, time and inoculum size) used.

CONCLUSIONS

This study revealed that H. alvei strains were able to enter and persist in a human epithelial cell line.

SIGNIFICANCE AND IMPACT OF THE STUDY

Our in vitro findings highlight the possibility that some H. alvei strains may exploit nonprofessional phagocytes or nonphagocytic cells to spread in vivo, which may be important for the persistence and establishment of an asymptomatic carrier state.

Total substitution of fish oil by vegetable oils in gilthead sea bream (Sparus aurata) diets: effects on hepatic Mx expression and some immune parameters

The use of vegetable oils in fish nutrition has been extensively studied; and recent work has focused attention on replacing fish oil with alternative fatty acid sources and their effect on the immune system. However, little is known about the effect of these oils on immune parameters such as the fish interferon system. In this study we evaluate the effect of two vegetable oils (linseed and soybean) on gilthead sea bream Mx expression and other innate immune parameters. Experimental diets were formulated where fish oil was totally replaced by vegetable oils or for a mixture of them (50% linseed and 50% soybean). Another diet prepared with pure fish oil was used as a control. Two experiments were carried out in order to evaluate growth, feed utilization, serum alternative complement pathway activity, serum lysozyme and phagocytic activity of head kidney leucocytes as well as Mx expression in the liver. In the first experiment fish were fed with experimental diets for 6 months and then, growth and feed utilization as well as immune parameters were analyzed. In the second experiment, fish from the previous feeding trial were injected with either a sub-lethal dose of Photobacterium damselae subsp. piscicida (94/99) or a synthetic dsRNA (Poly I:C) in order to stimulate an Mx response. The results show that total substitution of fish oil by vegetable oils decreased the growth of gilthead sea bream juveniles. Furthermore, both phagocytic activity and serum alternative complement pathway activity were significantly reduced by the inclusion of either vegetable oil individually in the sea bream diets, but the diet with mixed vegetable oils had no significant effect. There was no effect on serum lysozyme levels but the basal constitutive levels of Mx transcript expression in the liver were elevated in the fish fed the vegetable oil diets. The time-course of the Mx response to injection of Poly I:C was shorter in the fish fed the fish oil diet and the fish fed the diet based on a mixture of both vegetable oils showed a faster Mx response to bacterial injection. Following stimulation with Poly I:C or PDP the fish fed the vegetable oil based diets still maintained higher basal levels of hepatic Mx expression than the fish fed the fish oil diet which returned to undetectable levels.

Hemodynamic changes during reperfusion of the graft in an animal model of liver xenotransplantation

Our goal was to determine the hemodynamic changes that are witnessed during the initial minutes of reperfusion of the graft in liver xenotransplantation from pig to baboon.

METHOD

We studied a group of 12 baboons undergoing transplantation of a pig liver via the classic technique with arterial anastomosis to the aorta. The anesthesia technique was similar to that used in humans. Hemodynamic monitoring, due to the size of the recipient, consisted of heart rate (HR), mean arterial pressure (MAP), and central venous pressure (CVP) recorded at the beginning and end of each of the three phases: preanhepatic (A1, A2), anhepatic (B1, B2), and neohepatic (C1 and C2). We aimed to maintain the following values by means of crystalloids, colloids, and blood derivates: HR >50 beats/minute; MAP >60 mm Hg; and CVP >10 mm Hg.

RESULTS

Both HR and CVP remained unchanged throughout the procedure. MAP droped briefly after vascular clamping (B1) but not on reperfusion (C1).

CONCLUSION

In cirrhotic patients there is an autonomic dysfunction, demonstrated as cardiovascular instability at times like the clamping of major vessels and reperfusion of the graft. On the other hand, the intact baboon has an intact nervous system. After vascular clamping, the sharp decrease in venous return lead to an adequate vasopressor response. Likewise, the extreme vasodilatation involved with reperfusion managed to maintain MAP above 70 mm Hg.

Hemodynamic Assessment During Auxiliary Heterotopic Liver Transplantation With Portal Vein Arterialization in a Swine Model: Preliminary Report of 10 Transplants

Portal vein arterialization (PVA) is a technical variation of auxiliary heterotopic liver transplantation (AHLT) that is rarely studied but that simplifies the AHLT surgical technique because it does not act on the portal area. The objective of this study was to analyze the hemodynamic consequences of this auxiliary transplant in an experimental model.

MATERIALS AND METHODS

Ten AHLT-PVA were analyzed in a pig model. A PiCCO (Pulsion) monitor was used for the hemodynamic study of the recipient. The following were measured: cardiac index, (CI), systemic vascular resistance index, (SVRI), mean arterial pressure (MAP), global end-diastolic volume, central venous pressure, and intrathoracic blood volume. The measurements were taken at four times during transplant: at baseline, after inferior vena cava clamping, after graft reperfusion, and at closure.

RESULTS

After graft reperfusion there was a reduction in SVRI (968 +/- 168.03 vs 1686.25 +/- 290.66; P < .05) and in MAP, and there was an increase in CI. At the end of the transplant MAP and SVRI recovered (1254.2 +/- 225.79 vs 968 +/- 168.03; P < .05) but CI remained slightly high. The end-diastolic volume showed greater variation than central venous pressure, although this was only statistically significant at the inferior vena cava clamping phase (244.75 +/- 52.05 vs 333.37 +/- 170.13; P < .05).

DISCUSSION

Heterotopic liver transplantation with portal arterialization is well-tolerated hemodynamically. Graft reperfusion decreases SVRI and increases CI to compensate for this. This behavior, which in healthy recipients like ours is not a problem, could imply a contraindication in patients with a prior hyperdynamic state.

Expression of the glycoprotein of viral haemorrhagic septicaemia virus (VHSV) on the surface of the fish cell line RTG-P1 induces type 1 interferon expression in neighbouring cells

In the present study using a luciferase/Mx promoter reporter system, it was shown that the rainbow trout gonad cell line (RTG-P1), a fibroblastic cell line, produces IFN when transfected with a plasmid encoding the glycoprotein of VHSV but not with plasmid vector alone. Only a small percentage of the cells expressed the G protein on the surface membrane as indicated by immunostaining of transfected cells. When transfection was performed in the presence of monoclonal antibodies (Mab) to the glycoprotein, the production of interferon mRNA transcripts was reduced by over 50%. This indicates that the surface expression of G protein was the major mechanism of interferon induction and that most of the interferon was being expressed by cells neighbouring the transfected cells.

Risk factors of acute renal failure after liver transplantation

The objective of this study was to determine the risk factors of postoperative acute renal failure (ARF) in orthotopic liver transplantation (OLT). We reviewed 184 consecutive OLT. Postoperative ARF was defined as a persistent rise of 50% increase or more of the S-creatinine (S-Cr). The patients were classified as early postoperative ARF (E-ARF) (first week) and late postoperative ARF (L-ARF) (second to fourth week). Preoperative variables were age, sex, comorbidity, indication for OLT, Child-Pugh stage, united network for organ sharing status, analysis of the blood and urine, and donor's data. Intraoperative variables were systolic arterial pressure, mean arterial pressure, pulmonary capillary wedge pressure, cardiac index, and systemic vascular resistance index. Surgical technique, number of blood products transfused, need for adrenergic agonist drugs, and intraoperative complications were also important. Postoperative variables were duration of stay in the intensive care unit, time on mechanic ventilation, liver graft dysfunction, need for adrenergic agonist drugs, units of blood products infused, episodes of acute rejection, re-operations, and bacterial infections. Firstly we carried out a univariate statistical analysis, and secondly a logistic regression analysis. The risk factors for E-ARF were: pretransplant ARF (odds ratio (OR)=10.2, P=0.025), S-albumin (OR=0.3, P=0.001), duration of treatment with dopamine (OR=1.6, P=0.001), and grade II-IV dysfunction of the liver graft (OR=5.6, P=0.002). The risk factors for L-ARF were: re-operation (OR=3.1, P=0.013) and bacterial infection (OR=2.9, P=0.017). The development of E-ARF is influenced by preoperative factors such as ARF and hypoalbuminemia, as well as postoperative factors such as liver dysfunction and prolonged treatment with dopamine. The predicting factors of L-ARF differ from E-ARF and correspond to postoperative causes such as bacterial infection and surgical re-operation.

Complement consumption by Photobacterium damselae subsp. piscicida in seabream, red porgy and seabass normal and immune serum. Effect of the capsule on the bactericidal effect

A virulent strain of Photobacterium damselae subsp. piscicida (Pdp) was grown without (C form) or with (C+ form) glucose supplementation, the latter to enhance capsule formation. Both forms were resistant to killing by normal serum of seabream, red porgy and seabass. However, the C form was killed by immune serum of all three fish species while the C+ form was killed only by seabream and red porgy sera and to a lesser extent than the C form. Both C and C+ forms consumed complement in normal serum and this consumption was enhanced by precoating the bacteria in specific fish antibody. Complement consumption was greatest in seabass serum, especially with antibody-coated C+ form yet in this case the bacteria were not killed. The killing of the C form in immune serum of all three fish species was completely inhibited by EGTA/Mg(2+), indicating that the mechanism of complement activation leading to killing of the bacteria was by the classical pathway. The results suggest that immune serum killing by the classical complement pathway may provide some degree of protection against pasteurellosis, but enhanced expression of the capsule by Pdp in vivo may restrict complement-mediated killing, especially in immunised seabass.

Differential response of the systemic and pulmonary circulation related to disease severity of cirrhosis

BACKGROUND

In cirrhotic patients, the degree of hepatic insufficiency has been related to a physiological landmark: arterial vasodilatation. We sought to assess how the severity of disease, which was stratified according to the Child-Pugh criteria, influences the pulmonary and systemic circulation among patients undergoing liver transplantation.

METHODS

We studied 86 cirrhotic patients in three groups: grade A (n = 10), grade B (n = 54), and grade C (n = 22). The outurnes were classified based upon a complete hemodynamic profile obtained using a pulmonary artery catheter (RVEF, Baxter-Edwards, Calif, USA) after induction of anesthesia. The variables were mean arterial and pulmonary artery pressures and cardiac index (CI). Using standard formulae, afterload was calculated as elastance of systemic (Es) and pulmonary (Ep) arterial beds, expressed by the ratio of end-systolic pressure to stroke volume. The relation between pulmonary and systemic circulation was also evaluated by the ratio (Ep/Es).

RESULTS

Es was significantly lower in each class than in previous one. Also, Ep was smaller in class B than in class C patients. In addition, CI was significantly higher with disease severity.

CONCLUSION

We observed that the hyperdynamic circulation in cirrhosis is directly related to severity of disease. Nevertheless Ep/Es was progressively higher among each group; these data suggest that the hyperdynamic circulation is mainly due to circulatory alterations in the splanchnic area. We conclude that pulmonary vasodilatation is directly related to the severity of cirrhosis, although its evolution is independent of other vascular areas.

Prevention of hyperacute rejection in a model of orthotopic liver xenotransplantation from pig to baboon using polytransgenic pig livers (CD55, CD59, and H-transferase)

INTRODUCTION

The search for alternative sources for transplant organs leads us to the search for animals as an inexhaustible source of organs. The objective of this study was to analyze whether livers from polytransgenic pigs expressing the human complement regulatory proteins CD55 (hDAF), CD59, and alfa alpha1,2-fucosyltransferase (H-transferase), protected against hyperacute rejection after orthotopic liver xenotransplantation to a baboon and also to study pig liver function in a nonhuman primate.

MATERIALS AND METHODS

Nine liver transplants from pig to baboon were divided into two groups: a control group (n = 4) of genetically unmodified pigs and an experimental group (n = 5) of pigs transgenic for CD55, CD59, and H-transferase as donors. All the donating piglets obtained through hysterectomy were maintained in specific pathogen-free conditions. The selection of transgenic pig donors followed demonstration of transgene expression using monoclonal antibodies (antiCD55, antiCD59) and immunohistological studies on liver biopsies.

RESULTS

All animals in the control group developed hyperacute rejection with survival rates less than 16 hours without function of transplanted livers. In the experimental group none of the animals suffered hyperacute rejection. Survival in this group was between 13 and 24 hours. The livers were functional, producing bile and maintaining above 35% prothrombin activity. Only in one case was there primary dysfunction of the xenograft.

CONCLUSION

Polytransgenic livers for complement regulatory proteins prevent hyperacute rejection when xenotransplanted into a baboon.

Effects of rapid paracentesis on right ventricular-arterial coupling in liver transplantation

BACKGROUND

In cirrhotic patients intra-abdominal pressure (IAP) changes markedly modify splanchnic and systemic hemodynamics. Previous studies have evaluated the effects of increased IAP on steady-state cardiac performance, showing that right ventricular (RV) function becomes more depressed than that of the left ventricular. We sought to evaluate the effects of paracentesis on RV function and ventricular-arterial coupling among cirrhotics undergoing liver transplantation (OLT).

METHODS

Twelve cirrhotic patients undergoing OLT underwent hemodynamic profiles before and 5 minutes after paracentesis, employing a right ventricular ejection fraction catheter in the pulmonary artery. We studied heart rate, systolic pulmonary artery pressure, central venous pressure (CVP), stroke volume index (SVI), RV end-diastolic volume index (RVEDI), and RV ejection fraction. In addition RV stroke work index (RVSWI), RV end-diastolic compliance (RVEDC), RV end-systolic elastance (Ees), pulmonary artery effective elastance (Ea), and RV coupling efficiency (Ees/Ea ratio) were calculated employing standard formulas.

RESULTS

After removal of mean ascites volume of 5.6 +/- 2.2 L (range 4.0 to 8.04 L), SVI, RVEDI, RVSWI, and RVEDC were significantly increased and conversely CVP, Ees, and Ea were decreased with an ea/ea ratio unchanged.

CONCLUSIONS

Before paracentesis Ees/Ea is preserved by increased of RV contractility; after paracentesis the coupling was maintained.

In infectious pancreatic necrosis virus carrier Atlantic salmon, Salmo salar L., post-smolts, almost all kidney macrophages ex vivo contain a low level of non-replicating virus

The level of infection by infectious pancreatic necrosis virus (IPNV) of kidney macrophages from 12 asymptomatic carrier Atlantic salmon post-smolts was studied. Kidney leucocytes were fractionated on 34/51% Percoll gradients, allowed to adhere to plastic wells overnight, washed to remove non-adherent cells and cultured for up to 7 days with or without renewal of medium on day 3. On day 1, supernatants were harvested, macrophages were counted, lysed and IPNV in the supernatants and lysates was titred in chinook salmon embryo (CHSE-214) cells. The multiplicity of infection ranged between 1:2.2 and 1:7.4 (virus:macrophages). On day 3, the titres of IPNV in macrophage lysates decreased and in wells where the medium was renewed on day 3, IPNV was no longer detectable on day 7. In the supernatants, one fish was positive for IPNV on day 1, four fish on day 3 but none were detectably positive on day 7. In parallel wells in which the medium was not renewed, on day 7 IPNV was detected in macrophage lysates of three fish and the supernatants were also IPNV positive in two of these fish. This suggests that virus might be shed from infected macrophages and then reinfect other macrophages. When macrophages were serially diluted in wells and cultured for 24 h, IPNV could be cultured from macrophage lysates of wells containing between two and 70 macrophages. These results indicate that a very high proportion of the adherent kidney macrophages must be infected with very few non-replicating virions.