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CH3-6 of l-Rha and H-2 of d-Man give ROE correlation in the α-d-Manp-(1 → 4)-l-Rhap motif. C-2 in d-Man is shifted upfield in the 13C NMR spectrum of the β-d-Rhap-(1 → 3)-d-Manp motif.

Many children suffering from autism spectrum disorder (ASD) experience gastrointestinal (GI) conditions.

AIMS: To compare the circumpapillary and macular vessel density (cpVD/mVD) of eyes with temporal visual field (VF) defect and band atrophy (BA) of the optic nerve and normal controls using OCTA and to verify the association of VD parameters with circumpapillary retinal nerve fibre layer (cpRNFL) thickness, macular ganglion cell complex (mGCC) thickness and VF loss. METHODS: Thirty-three eyes of 26 patients with BA and 42 eyes of 22 age-matched normal controls underwent OCT + OCTA scanning. cpVD and cpRNFL were expressed as average and sector measurements. mVD and mGCC were calculated as averages and in quadrants and hemiretinas. VF loss was estimated using the 24-2 and the 10-2 protocols. Generalized estimated equation models were used for comparisons and area under the receiver operating characteristics (AROC) were calculated. RESULTS: Compared with controls, BA eyes displayed smaller average cpVD and mVD values (p

The Campylobacter jejuni capsule type HS1 complex is one of the most common serotypes identified worldwide, and consists of strains typing as HS1, HS1/44, HS44 and HS1/8. The capsule structure of the HS1 type strain was shown previously to be composed of teichoic-acid like glycerol-galactosyl phosphate repeats [4-)-α-D-Galp-(1–2)-Gro-(1-P-] with non-stoichiometric fructose branches at the C2 and C3 of Gal and non-stoichiometric methyl phosphoramidate (MeOPN) modifications on the C3 of the fructose. Here, we demonstrate that the capsule of an HS1/44 strain is identical to that of the type strain of HS1, and the capsule of HS1/8 is also identical to HS1, except for an additional site of MeOPN modification at C6 of Gal. The DNA sequence of the capsule locus of an HS44 strain included an insertion of 10 genes, and the strain expressed two capsules, one identical to the HS1 type strain, but with no fructose branches, and another composed of heptoses and MeOPN. We also characterize a HS1 capsule biosynthesis gene, HS1.08, as a fructose transferase responsible for the attachment of the β-D-fructofuranoses residues at C2 and C3 of the Gal unit. In summary, the common component of all members of the HS1 complex is the teichoic-acid like backbone that is likely responsible for the observed sero-cross reactivity.

Purpose: to describe a patient with visual field (VF) defect from an occipital lobe lesion that was found to have macular ganglion cells complex (GCC) quadrantic reduction without significant peripapillary retinal nerve fiber layer (RNFL) loss on optical coherence tomography (OCT). To emphasize that macular GCC loss may be the major ocular manifestation of trans-synaptic optic pathway degeneration in occipital lobe lesions. Observations: A 15-year-old female was investigated after a VF examination revealed a right homonymous inferior quadrantanopia. Fundoscopic examination was completely normal as were the peripapillary retinal nerve fiber layer (RNFL) thickness measurements on OCT. Macular thickness measurements however, revealed superior homonymous quadrantic GCL reduction evidencing retinal neuronal loss in direct correspondence with her VF defect. Magnetic resonance imaging showed a localized left occipital lobe gliotic lesion as the explanation for her VF defect. Conclusions and Importance: Small post-geniculate optic pathway lesions may lead to retrograde trans-synaptic degeneration that can be detected on OCT-measured macular GCL measurements despite normal peripapillary RNFL estimates. Awareness of such occurrence in important to avoid diagnostic confusion with other anterior visual pathway diseases. Keywords: Optical coherence tomography, Retinal ganglion cells layer, Occipital lesions, Retrograde trans-synaptic degeneration

Enterotoxigenic Escherichia coli (ETEC), Campylobacter jejuni (CJ), and Shigella sp. are major causes of bacterial diarrhea worldwide, but there are no licensed vaccines against any of these pathogens. Most current approaches to ETEC vaccines are based on recombinant proteins that are involved in virulence, particularly adhesins. In contrast, approaches to Shigella and CJ vaccines have included conjugate vaccines in which Shigella lipopolysaccharides (LPS) or CJ capsule polysaccharides are chemically conjugated to proteins. We have explored the feasibility of developing a multi-pathogen vaccine by using ETEC proteins as conjugating partners for CJ and Shigella polysaccharides. We synthesized three vaccines in which two CJ polysaccharides were conjugated to two recombinant ETEC adhesins based on CFA/I (CfaEB) and CS6 (CssBA), and LPS from Shigella flexneri was also conjugated to CfaEB. The vaccines were immunogenic in mice as monovalent, bivalent and trivalent formulations. Importantly, functional antibodies capable of inducing hemaglutination inhibition (HAI) of a CFA/I expressing ETEC strain were induced in all vaccines containing CfaEB. These data suggest that conjugate vaccines could be a platform for a multi-pathogen, multi-serotype vaccine against the three major causes of diarrheal disease worldwide.

Background. A number of orbital diseases may be evaluated based on the degree of exophthalmos, but there is still no gold standard method for the measurement of this parameter. In this study we compare two exophthalmometry measurement methods (digital photography and clinical) with regard to reproducibility and the level of correlation and agreement with measurements obtained with Computerized Tomography (CT) measurements. Methods. Seventeen patients with bilateral proptosis and 15 patients with normal orbits diseases were enrolled. Patients underwent orbital CT, Hertel exophthalmometry (HE) and standardized frontal and side facial photographs by a single trained photographer. Exophthalmometry measurements with HE, the digital photographs and axial CT scans were obtained twice by the same examiner and once by another examiner. Pearson correlation coefficient (PCC) was used to assess correlations between methods. Validity between methods was assessed by mean differences, interintraclass correlation coefficients (ICC’s), and Bland–Altman plots. Results. Mean values were significantly higher in the proptosis group (34 orbits) than in the normal group (30 orbits), regardless of the method. Within each group, mean digital exophthalmometry measurements (24.32 ± 5.17 mm and 18.62 ± 3.87 mm) were significantly greater than HE measurements (20.87 ± 2.53 mm and 17.52 ± 2.67 mm) with broader range of standard deviation. Inter-/intraclass correlation coefficients were 0.95/0.93 for clinical, 0.92/0.74 for digital, and 0.91/0.95 for CT measurements. Correlation coefficients between HE and CT scan measurements in both groups of subjects (r = 0.84 and r = 0.91, p<0.05) were greater than those between digital and CT scan measurements (r = 0.61 and r = 0.75, p<0.05). On the Bland–Altman plots, HE showed better agreement to CT measurements compared to the digital photograph method in both groups studied. Conclusions. Although photographic digital exophthalmometry showed strong correlation and agreement with CT scan measurements, it still performs worse than and is not as accurate as clinical Hertel exophthalmometry. This trail is registered with NCT01999790.

Optic disc pit is a rare congenital anomaly that can cause serous macular detachment. It has no universally accepted single treatment. Recently, several investigators have performed new procedures to directly seal the pit. Herein, we report a case showing a promising method for optic pit maculopathy surgical treatment. We created an inverted internal limiting membrane flap and fold it over the pit to promote barrier in order to stop further fluid accumulation. Gradual absorption of subretinal fluid was observed over 12 months of follow-up. Optical coherence tomography can demonstrate internal limiting membrane folded over the pit and progressive subretinal fluid resolution. This technique resulted in a satisfactory anatomic outcome with good functional improvement in the best-corrected visual acuity. RESUMO A fosseta do disco óptico é uma rara anomalia con gênita que pode causar descolamento de retina seroso na mácula. Não há um tratamento cirúrgico padrão universalmente aceito. Recentemente, cirurgiões têm realizado procedimentos novos que visam selar o buraco diretamente. Esse caso clínico mostra um método promissor para o tratamento cirúrgico da maculopatia causada pela fosseta do disco. Optamos por criar um flap invertido com a membrana limitante interna, dobrando-o sobre a fosseta para promover uma barreira, impedindo o acúmulo de fluido. A absorção gradual do líquido subretiniano foi observada ao longo de 12 meses de acompanhamento. Imagens de tomografia de coerência óptica podem demonstrar a membrana limitante interna dobrada sobre a fosseta e a resolução progressiva do fluido subretiniano. Esta técnica resultou em um resultado anatômico satisfatório com boa melhora funcional na acuidade visual.

OBJECTIVES: To determine the effect of panretinal photocoagulation (PRP) on the peripapillary retinal nerve fiber layer (RNFL) in nonglaucomatous patients with proliferative diabetic retinopathy (PDR). METHODS: This is a prospective, single center, observational study. Thirty-eight eyes of 26 diabetic patients underwent PRP for proliferative diabetic retinopathy. Peripapillary RNFL thickness was measured using scanning laser polarimetry (SLP) with variable corneal compensation (GDx VCC; by Carl Zeiss Meditec, Dublin, CA) and spectral-domain optical coherence tomography (OCT) (Heidelberg Spectralis, Carlsbad, USA) at baseline and 12 months after PRP was performed. RESULTS: Thirty-eight eyes of 26 patients (15 female) with a mean age of 53.7 years (range 26 to 74 years) were recruited. No significant difference was found among all RNFL thickness parameters tested by GDx VCC software (p=0.952, 0.464 and 0.541 for temporal-superior-nasal-inferior-temporal (TSNIT) average, superior average, inferior average, respectively). The nerve fiber indicator (NFI) had a nonsignificant increase (p=0.354). The OCT results showed that the average RNFL thickness (360° measurement) decreased nonsignificantly from 97.2 mm to 96.0 mm at 1 year post-PRP (p=0.469). There was no significant difference when separately analyzing all the peripapillary sectors (nasal superior, temporal superior, temporal, temporal inferior, nasal inferior and nasal thickness). CONCLUSION: Our results suggest that PRP, as performed in our study, does not cause significant changes in peripapillary RNFL in diabetic PDR patients after one year of follow-up.

Campylobacter jejuni colonizes the chicken gut at a high density without causing disease. However, consumption of poultry products contaminated with this bacterium causes gastroenteritis in humans. Therefore, it is critically important to reduce the Campylobacter burden in poultry products to prevent transmission to humans. Evidence indicates that enhancing intestinal mucosal immune responses is of paramount importance for preventing or reducing Campylobacter colonization in chickens. In view of this, the present study was undertaken to evaluate host responses to different C. jejuni-derived ligands, including lipooligosaccharide (LOS), outer membrane proteins (OMPs), and genomic DNA, with the ultimate goal of identifying a ligand with potent immunostimulatory capacity to serve as a mucosal vaccine adjuvant against enteric infections in chickens. The results revealed that C. jejuni pathogen-associated molecular patterns (PAMPs) varied in their ability to induce the expression of cytokines and chemokines in chicken macrophages and cecal tonsil mononuclear cells and nitric oxide production in macrophages. In addition, C. jejuni OMPs demonstrated superior activity over LOS and DNA ligands in eliciting cytokine expression associated with T helper (Th)1 and Th2 responses (interferon [IFN]-γ and interleukin [IL]-13, respectively), in addition to expression of pro-inflammatory cytokines (IL-1β), chemokine (CXCLi2), and regulatory cytokines (IL-10 and TGFβ1/4) in cecal tonsil cells. Importantly, in addition to their ability to induce innate responses, OMPs could also function as antigens to elicit C. jejuni-specific antibody responses and thereby confer dual protection against C. jejuni infection. Further studies are required to assess the protective efficacy of C. jejuni OMPs against C. jejuni infection in chickens.

Campylobacter jejuni is a major cause of infectious diarrhea worldwide. Increasing incidence of C. jejuni is attributed to new non-culture based detection methods and antibiotic resistance is unfortunately on the rise, necessitating development of interventions. Therapeutics development like vaccines have been hampered by lack of a small animal model that recapitulates campylobacteriosis symptoms. To better facilitate vaccine efficacy testing, we adapted a recently-published mouse C. jejuni infection model to adult mice fed a zinc-deficient diet and pre-treated with antibiotics prior to oral infection with C. jejuni strain 81–176. Non-vaccinated infected mice develop diarrhea, lose weight and show increased expression of fecal inflammatory markers indicating development of campylobacteriosis. We tested whether an 81–176 C. jejuni capsule conjugate vaccine delivered with a potent liposome adjuvant containing monophosphoryl lipid A and QS-21 known as ALFQ could protect mice against 81–176. Vaccinated mice developed high levels of anti-CPS IgG1 and IgG2b titers and serum bactericidal responses against 81–176. Vaccinated infected mice were protected against development of diarrhea, did not lose weight, and had significantly lower levels of fecal inflammatory marker expression. Importantly, vaccinated infected animals were protected against C. jejuni colonization indicating that parenteral vaccination with a conjugate vaccine plus the ALFQ adjuvant may provide protection against both C. jejuni disease and colonization. These promising results support further development of a multivalent C. jejuni conjugate vaccine platform delivered with potent adjuvant systems for use in human clinical studies.

A large number of children in the autism spectrum disorder suffer from gastrointestinal (GI) conditions, such as constipation and diarrhea. Clostridium bolteae is a part of a set of pathogens being regularly detected in the stool samples of hosts affected by GI and autism symptoms. Accompanying studies have pointed out the possibility that such microbes affect behaviour through the production of neurotoxic metabolites in a so-called, gut-brain connection. As an extension of our Clostridium difficile polysaccharide (PS)-based vaccine research, we engaged in the discovery of C. bolteae surface carbohydrates. So far, studies revealed that C. bolteae produces a specific immunogenic PS capsule comprised of disaccharide repeating blocks of mannose (Manp) and rhamnose (Rhap) units: α-D-Manp-(1→[-4)-β-D-Rhap- (1→3)-α-D-Manp-(1→]n. For vaccinology and further immunogenic experiments, a method to produce C. bolteae PS conjugates has been developed, along with the chemical syntheses of the PS non-reducing end linkage, with D-Rha or L-Rha, α-D-Manp-(1→4)-α-D-Rhap- (1→O(CH2)5NH2 and α-D-Manp-(1→4)-α-L-Rhap-(1→O(CH2)5NH2, equipped with an aminopentyl linker at the reducing end for conjugation purposes. The discovery of C. bolteae PS immunogen opens the door to the creation of non-evasive diagnostic tools to evaluate the frequency and role of this microbe in autistic subjects and to a vaccine to reduce colonization levels in the GI tract, thus impeding the concentration of neurotoxins.

Campylobacter jejuni polysaccharide capsules (CPS) are characterized by the presence of nonstoichiometric O -methyl phosphoramidate (MeOPN) modifications. The lack of stoichiometry is due to phase variation at homopolymeric tracts within the MeOPN transferase genes. C. jejuni strain 81-176 contains two MeOPN transferase genes and has been shown previously to contain MeOPN modifications at the 2 and 6 positions of the galactose (Gal) moiety in the CPS. We demonstrate here that one of the two MeOPN transferases, encoded by CJJ81176_1435, is bifunctional and is responsible for the addition of MeOPN to both the 2 and the 6 positions of Gal. A new MeOPN at the 4 position of Gal was observed in a mutant lacking the CJJ81176_1435 transferase and this was encoded by the CJJ81176_1420 transferase. During routine growth of 81-176, the CJJ81176_1420 transferase was predominantly in an off configuration, while the CJJ81176_1435 transferase was primarily on. However, exposure to normal human serum selected for cells expressing the CJJ81176_1420 transferase. MeOPN modifications appear to block binding of naturally occurring antibodies to the 81-176 CPS. The absence of MeOPN-4-Gal resulted in enhanced sensitivity to serum killing, whereas the loss of MeOPN-2-Gal and MeOPN-6-Gal resulted in enhanced resistance to serum killing, perhaps by allowing more MeOPN to be put onto the 4 position of Gal. IMPORTANCE Campylobacter jejuni undergoes phase variation in genes encoding surface antigens, leading to the concept that a strain of this organism consists of multiple genotypes that are selected for fitness in various environments. Methyl phosphoramidate modifications on the capsule of C. jejuni block access of preexisting antibodies in normal human sera to the polysaccharide chain, thus preventing activation of the classical arm of the complement cascade. We show that the capsule of strain 81-176 contains more sites of MeOPN modifications than previously recognized and that one site, on the 4 position of galactose, is more critical to complement resistance than the others. Exposure to normal human serum selects for variants in the population expressing this MeOPN modification.

Clostridium difficile vaccines composed of surface polysaccharides (PSs) have the potential to simultaneously control infection and colonization levels in humans. Hot water-phenol treatment of C. difficile biomass can extricate water-soluble PS-I and PS-II; and water- and phenol-soluble PS-III. C. difficile vaccines based on PS-II have attracted the most attention due its facile purification and ubiquitous expression by C. difficile ribotypes. Anti PS-II antibodies recognize both C. difficile vegetative cell and sporulating preparations and confer protection against C. difficile infection in a mouse model. The design of such an efficacious C. difficile PS-II conjugate vaccine is described here.

Clostridium difficile vaccines composed of surface polysaccharides (PSs) have the potential to simultaneously control infection and colonization levels in humans. Hot water-phenol treatment of C. difficile biomass can extricate water-soluble PS-I and PS-II; and water- and phenol-soluble PS-III. C. difficile vaccines based on PS-II have attracted the most attention due its facile purification and ubiquitous expression by C. difficile ribotypes. Anti PS-II antibodies recognize both C. difficile vegetative cell and sporulating preparations and confer protection against C. difficile infection in a mouse model. The design of such an efficacious C. difficile PS-II conjugate vaccine is described here.

Campylobacter jejuni is a leading cause of traveler's diarrhea. Previously, we have shown that a C. jejuni capsule polysaccharide (CPS) conjugate vaccine can fully prevent C.jejuni diarrhea in non-human primates. C.jejuni CPSs are decorated with non-stoichiometric amounts of O-methyl phosphoramidate (MeOPN) units that are key serospecific markers. In the case of C.jejuni serotype complex HS23/36, the MeOPN are at positions 2 and 6 of the CPS galactose (Gal). We describe here the synthesis of the p-methoxyphenyl glycoside of MeOPN→6-α-D-Galp, and its immunodetection by antisera raised by C.jejuni CPS conjugates with MeOPN at primary positions. The synthetic approach in this work served as the foundation for a similar MeOPN→6-Gal construct used in a conjugate vaccine, whose synthesis, immunogenicity and efficacy will be described elsewhere.

Background Campylobacter jejuni is a leading bacterial cause of food-borne illness in humans. Symptoms range from mild gastroenteritis to dysentery. Contaminated chicken meat is the most common cause of infection. Broiler chickens become colonized with high numbers of C. jejuni in the intestinal tract, but do not become clinically ill. Vaccination of broiler chicks to control colonization by C. jejuni is challenging because immune function is limited in the first 2 weeks post-hatch and immune suppressive maternal antibodies are common. In addition, there is little time for induction of immunity, since broilers reach slaughter weight by 5–6 weeks of age. In the current study the immunogenicity of a C. jejuni capsular polysaccharide—diphtheria toxoid conjugated vaccine (CPSconj), administered subcutaneously with various adjuvants was assessed and the efficacy of vaccination for reducing cecal colonization after experimental challenge was evaluated by determining colony-forming units (CFU) of C. jejuni in cecal contents. Results The CPSconj vaccine was immunogenic when administered as three doses at 3, 4 and 5 weeks of age to specific pathogen free chicks lacking maternal antibodies (seroconversion rates up to 75%). Commercial broiler chicks (having maternal antibodies) receiving two doses of CPSconj vaccine at 7 and 21 days of age did not seroconvert before oral challenge at 29 days, but 33% seroconverted post challenge; none of the placebo-injected, challenged birds seroconverted. Vaccinated birds had significantly lower numbers of C. jejuni in cecal contents than control birds at necropsy (38 days of age). CFU of C. jejuni did not differ significantly among groups of birds receiving CPSconj vaccine with different adjuvants. In two trials, the mean reduction in CFU associated with vaccination was 0.64 log10 units. Conclusions The CPSconj vaccine was immunogenic in chicks lacking maternal antibodies, vaccinated beginning at 3 weeks of age. In commercial broiler birds (possessing maternal antibodies) vaccinated at 7 and 21 days of age, 33% of birds seroconverted by 9 days after challenge, and there was a modest, but significant, reduction in cecal counts of C. jejuni. Further studies are needed to optimize adjuvant, route of delivery and scheduling of administration of this vaccine.