Haemophilus influenzae carriage and antibiotic resistance profile in Belgian infants over a three-year period (2016–2018)

BackgroundNon-typeable Haemophilus influenzae has become increasingly important as a causative agent of invasive diseases following vaccination against H. influenzae type b. The emergence of antibiotic resistance underscores the necessity to investigate typeable non-b carriage and non-typeable H. influenzae (NTHi) in children.MethodsNasopharyngeal swab samples were taken over a three-year period (2016–2018) from 336 children (6–30 months of age) attending daycare centers (DCCs) in Belgium, and from 218 children with acute otitis media (AOM). Biotype, serotype, and antibiotic resistance of H. influenzae strains were determined phenotypically. Mutations in the ftsI gene were explored in 129 strains that were resistant or had reduced susceptibility to beta-lactam antibiotics. Results were compared with data obtained during overlapping time periods from 94 children experiencing invasive disease.ResultsOverall, NTHi was most frequently present in both carriage (DCC, AOM) and invasive group. This was followed by serotype “f” (2.2%) and “e” (1.4%) in carriage, and “b” (16.0%), “f” (11.7%), and “a” (4.3%) in invasive strains. Biotype II was most prevalent in all studied groups, followed by biotype III in carriage and I in invasive strains. Strains from both groups showed highest resistance to ampicillin (26.7% in carriage vs. 18.1% in invasive group). A higher frequency of ftsI mutations were found in the AOM group than the DCC group (21.6 vs. 14.9% – p = 0.056). Even more so, the proportion of biotype III strains that carried a ftsI mutation was higher in AOM compared to DCC (50.0 vs. 26.3% – p < 0.01) and invasive group.ConclusionIn both groups, NTHi was most frequently circulating, while specific encapsulated serotypes for carriage and invasive group were found. Biotypes I, II and III were more frequently present in the carriage and invasive group. The carriage group had a higher resistance-frequency to the analyzed antibiotics than the invasive group. Interestingly, a higher degree of ftsI mutations was found in children with AOM compared to DCC and invasive group. This data helps understanding the H. influenzae carriage in Belgian children, as such information is scarce

Psip1/Ledgf p52 Binds Methylated Histone H3K36 and Splicing Factors and Contributes to the Regulation of Alternative Splicing

Increasing evidence suggests that chromatin modifications have important roles in modulating constitutive or alternative splicing. Here we demonstrate that the PWWP domain of the chromatin-associated protein Psip1/Ledgf can specifically recognize tri-methylated H3K36 and that, like this histone modification, the Psip1 short (p52) isoform is enriched at active genes. We show that the p52, but not the long (p75), isoform of Psip1 co-localizes and interacts with Srsf1 and other proteins involved in mRNA processing. The level of H3K36me3 associated Srsf1 is reduced in Psip1 mutant cells and alternative splicing of specific genes is affected. Moreover, we show altered Srsf1 distribution around the alternatively spliced exons of these genes in Psip1 null cells. We propose that Psip1/p52, through its binding to both chromatin and splicing factors, might act to modulate splicing

Role of PSIP1/LEDGF/p75 in lentiviral infectivity and integration targeting

To replicate, lentiviruses such as HIV must integrate DNA copies of their RNA genomes into host cell chromosomes. Lentiviral integration is favored in active transcription units, which allows efficient viral gene expression after integration, but the mechanisms directing integration targeting are incompletely understood. A cellular protein, PSIP1/LEDGF/p75, binds tightly to the lentiviral-encoded integrase protein (IN), and has been reported to be important for HIV infectivity and integration targeting.Here we report studies of lentiviral integration targeting in 1) human cells with intensified RNAi knockdowns of PSIP1/LEDGF/p75, and 2) murine cells with homozygous gene trap mutations in the PSIP1/LEDGF/p75 locus. Infections with vectors derived from equine infections anemia virus (EIAV) and HIV were compared. Integration acceptor sites were analyzed by DNA bar coding and pyrosequencing.In both PSIP1/LEDGF/p75-depleted cell lines, reductions were seen in lentiviral infectivity compared to controls. For the human cells, integration was reduced in transcription units in the knockdowns, and this reduction was greater than in our previous studies of human cells less completely depleted for PSIP1/LEDGF/p75. For the homozygous mutant mouse cells, similar reductions in integration in transcription units were seen, paralleling a previous study of a different mutant mouse line. Integration did not become random, however-integration in transcription units in both cell types was still favored, though to a reduced degree. New trends also appeared, including favored integration near CpG islands. In addition, we carried out a bioinformatic study of 15 HIV integration site data sets in different cell types, which showed that the frequency of integration in transcription units was correlated with the cell-type specific levels of PSIP1/LEDGF/p75 expression

Complication rate after carotid endarterectomy comparing patch angioplasty and primary closure

Background: Carotid endarterectomy (CEA) reduces the risk for stroke in patients with internal carotid artery stenosis. The optimal surgical technique remains subject of debate. Literature suggests patch angioplasty reduces complication risk. However, primary closure shortens cross-clamp times and eliminates graft-specific complications. This study aimed to assess complication rate after CEA with selective patching. Methods: A total of 213 consecutive CEAs over a 3-year period from January 5th, 2011 to December 19th, 2013 were retrospectively analyzed. Postoperative complications were evaluated within 1 month after surgery. Results: Primary closure was used in 110 operations and patch angioplasty in 103 procedures. Primary closure was performed when the carotid artery had a diameter above 5 mm, when there was a high carotid bifurcation, and when the contralateral carotid artery was occluded. After primary closure, we found 4 (3.6%) complications: 2 (1.8%) bleeding and 2 (1.8%) cranial nerve damage. After patch angioplasty 5 (4.9%) complications occurred: 1 (1.0%) bleeding, 2 (1.9%) cranial nerve damage, 1 (1.0%) cerebrovascular event, and 1 (1.0%) cerebral hyperperfusion resulting in mortality. There was no higher complication risk after primary closure (P = 0.68). Clamp time was significantly longer when using patch angioplasty (P < 0.001). Conclusions: Primary closure appears to be an equivalent closure technique compared with patch angioplasty when used in selected patients

Apraclonidine and my pupil

Purpose Used in the diagnosis of Horner's syndrome, apraclonidine 1% dilatates the involved eye due to denervation supersensitivity. Recent literature suggests that in healthy volunteers, apraclonidine provokes a mild miotic effect. Since the comparison of both the pathologic and the non-pathologic eye is important, we wanted to further investigate the effect of apraclonidine on the healthy eye. By measuring the effect on the pupil intermittently over a few hours, we tried to determine the best moment for evaluation after instillation with apraclonidine. Therefore, the effect of apraclonidine on pupillary parameters was investigated in 14 healthy volunteers. Methods Infrared pupillography was used to measure the scotopic pupil diameter and the dynamic pupil responses to light. The first measurements were performed prior to instillation of apraclonidine. Measurements were retaken 30, 60, 90, 120, 180, 240, 300 and 360 min after random instillation of one eye with one drop of 1% apraclonidine. Results The anisocoria after dark adaptation and at minimum pupil diameter differed significantly for the measurements obtained 30 and 60 min after instillation with apraclonidine. The eye with apraclonidine drops showed relative miosis and an increased amplitude of constriction to light. No significant influence was found on the latency, the constriction velocity and redilation velocity. Conclusions Instillation of apraclonidine 1% in healthy subjects causes relative miosis, which is most pronounced after 30-60 min. The amplitude of constriction to light also differs significantly. The relative miotic effect of apraclonidine could be explained by the alpha-2 receptor agonistic effect which is more pronounced than the alpha-1 agonistic effect in healthy subjects. In patients with Horner's syndrome, the alpha-1 agonistic effect will dominate because of the supersensitivity of the alpha-1 receptors, resulting in relative mydriasis. These findings stress the necessity to instill the unaffected eye in diagnosing a suspected Horner's pupil

The pupils of migraine patients : preliminary results

Aim To date there is no consensus whether there is a sympathetic or a parasympathetic disturbance in migraine; most pupillometric studies point towards a sympathic hypofunction. (1-4) By testing migraine patients both during an attack and in the headache free interval, we wanted to compare whether a potential sympathetic dysfunction increases during an attack by using apraclonidine 1%, an alpha adrenergic agonist. Methods We used infrared pupillometry to measure the dark adapted and light adapted pupil diameter. The minimal diameter, latency, amplitude, constriction and redilatation velocity of the light reflex were measured as well. We studied 31 controls and 42 migraine patients interictally, after a migraine-free period of at least 15 days. None of the migraine patients took prophylactic medication. Fourteen migraine patients were also studied ictally; they were not allowed to take any attack-aborting medication before or during the test. Results We found no differences between migraine patients with and without aura. None of the parameters correlated with the headache side in patients with unilateral migraine. We found no significant difference between migraine patients and controls, neither interictally, nor ictally. The pupil parameters of migraine patients did not differ significantly between and during the attack. However after administration of apraclonidine 1%, migraine patients had a longer latency compared to controls. This increase in latency was more pronounced ictally (right: P = 0.046, left: P = 0.023) than interictally (right: P = 0.075, left: P = 0.021). Conclusion We assume there is a subtle pupillary sympathetic hypofunction in migraine patients which is unmasked after administration of apraclonidine 1%. The sympathetic hypofunction creates a sympathetic hypersensitivity that causes the prolonged latency. References 1. Ophthalmic Physiol Opt. 2005;25(3):240-5. 2. Psychiatry 1990;53:121-5. 3. Headache 1985;25:40-8. 4. Clin Auton Res. 2003;13:16-21

Autonomic function in migraine patients: ictal and interictal pupillometry

Objective and Background: Pupillometric investigations into migraine have suggested that an autonomic disturbance is part of the pathogenesis of that condition. This observation is controversial, however, which may reflect that the putative sympathetic hypofunction is either subtle or transient. In this study, we assessed the sympathetic function of migraine patients and controls during both a symptom-free phase and a migraine attack, and challenged patients with apraclonidine to reveal small changes in autonomic function. Methods: Infrared pupillometry was used to measure pupillometric parameters in 37 controls and 46 migraine patients in the interictal phase of disease. Fifteen migraine patients were also studied during a migraine attack. In addition, 26 controls and 18 migraine patients were tested interictally both with and without apraclonidine. Of these 18 migraine patients, seven were also tested with and without apraclonidine during a migraine attack. Results: We found no significant differences between migraine patients and controls in the interictal phase. Additionally, no differences in pupil parameters were detected during the migraine attack. However, after administration of apraclonidine, migraine patients had a longer latency of the light reflex compared with controls. This increase in latency was more pronounced ictally (oculus dexter: P=.046, oculus sinister: P=.023) than interictally (oculus dexter: P=.075, oculus sinister: P=.021). Conclusions: We conclude that there is evidence for a subtle pupillary sympathetic hypofunction in migraine patients, observed as a prolonged latency to light reflex, which is revealed after the administration of apraclonidine