Potent immunogenicity and protective efficacy of a multi-pathogen vaccination targeting Ebola, Sudan, Marburg and Lassa viruse.

Viral haemorrhagic fevers (VHF) pose a significant threat to human health. In recent years, VHF outbreaks caused by Ebola, Marburg and Lassa viruses have caused substantial morbidity and mortality in West and Central Africa. In 2022, an Ebola disease outbreak in Uganda caused by Sudan virus resulted in 164 cases with 55 deaths. In 2023, a Marburg disease outbreak was confirmed in Equatorial Guinea and Tanzania resulting in over 49 confirmed or suspected cases; 41 of which were fatal. There are no clearly defined correlates of protection against these VHF, impeding targeted vaccine development. Any vaccine developed should therefore induce strong and preferably long-lasting humoral and cellular immunity against these viruses. Ideally this immunity should also cross-protect against viral variants, which are known to circulate in animal reservoirs and cause human disease. We have utilized two viral vectored vaccine platforms, an adenovirus (ChAdOx1) and Modified Vaccinia Ankara (MVA), to develop a multi-pathogen vaccine regime against three filoviruses (Ebola virus, Sudan virus, Marburg virus) and an arenavirus (Lassa virus). These platform technologies have consistently demonstrated the capability to induce robust cellular and humoral antigen-specific immunity in humans, most recently in the rollout of the licensed ChAdOx1-nCoV19/AZD1222. Here, we show that our multi-pathogen vaccines elicit strong cellular and humoral immunity, induce a diverse range of chemokines and cytokines, and most importantly, confers protection after lethal Ebola virus, Sudan virus and Marburg virus challenges in a small animal model.

Iron chelation increases beige fat differentiation and metabolic activity, preventing and treating obesity.

Beige and brown fat consume glucose and lipids to produce heat, using uncoupling protein 1 (UCP1). It is thought that full activation of brown adipose tissue (BAT) may increase total daily energy expenditure by 20%. Humans normally have more beige and potentially beige-able fat than brown fat. Strategies to increase beige fat differentiation and activation may be useful for the treatment of obesity and diabetes. Mice were fed chow or high-fat diet (HFD) with or without the iron chelator deferasirox. Animals fed HFD + deferasirox were markedly lighter than their HFD controls with increased energy expenditure (12% increase over 24 h, p < 0.001). Inguinal fat from HFD + deferasirox mice showed increased beige fat quantity with greater Ucp1 and Prdm16 expression. Inguinal adipose tissue explants were studied in a Seahorse bioanalyser and energy expenditure was significantly increased. Deferasirox was also effective in established obesity and in ob/ob mice, indicating that intact leptin signalling is not needed for efficacy. These studies identify iron chelation as a strategy to preferentially activate beige fat. Whether activating brown/beige fat is effective in humans is unproven. However, depleting iron to low-normal levels is a potential therapeutic strategy to improve obesity and related metabolic disorders, and human studies may be warranted.

A Multi-Filovirus Vaccine Candidate: Co-Expression of Ebola, Sudan, and Marburg Antigens in a Single Vector.

In the infectious diseases field, protective immunity against individual virus species or strains does not always confer cross-reactive immunity to closely related viruses, leaving individuals susceptible to disease after exposure to related virus species. This is a significant hurdle in the field of vaccine development, in which broadly protective vaccines represent an unmet need. This is particularly evident for filoviruses, as there are multiple family members that can cause lethal haemorrhagic fever, including Zaire ebolavirus, Sudan ebolavirus, and Marburg virus. In an attempt to address this need, both pre-clinical and clinical studies previously used mixed or co-administered monovalent vaccines to prevent filovirus mediated disease. However, these multi-vaccine and multi-dose vaccination regimens do not represent a practical immunisation scheme when considering the target endemic areas. We describe here the development of a single multi-pathogen filovirus vaccine candidate based on a replication-deficient simian adenoviral vector. Our vaccine candidate encodes three different filovirus glycoproteins in one vector and induces strong cellular and humoral immunity to all three viral glycoproteins after a single vaccination. Crucially, it was found to be protective in a stringent Zaire ebolavirus challenge in guinea pigs in a one-shot vaccination regimen. This trivalent filovirus vaccine offers a tenable vaccine product that could be rapidly translated to the clinic to prevent filovirus-mediated viral haemorrhagic fever.

Right miniparasternotomy may be a good minimally invasive alternative to full sternotomy for cardiac valve operations: a propensity-adjusted analysis.

BACKGROUND: Limited real-world data existed for mini-parasternotomy approach with good sample size in Asian cohorts and most previous studies were eclipsed by case heterogeneity. The goal of this study was to compare safety and quality outcomes of cardiac non-coronary valve operations by mini-parasternotomy and full sternotomy approaches on risk-adjusted basis. METHODS From our hospital database, we retrieved the cases of non-coronary valve operations from 1 January 2005 to 31 December 2012, including re-do, emergent, and combined procedures. Estimated EuroScore-II and propensity score for choosing mini-parasternotomy were adjusted for in the regression models on hospital mortality, complications (pneumonia, stroke, sepsis, etc.), and quality parameters (length of stay, ICU time, ventilator time, etc.). Non-complicated cases, defined as survival to discharge, ventilator use not over one week, and intensive care unit stay not over two weeks, were used for quality parameters. RESULTS: There were 283 mini-parasternotomy and 177 full sternotomy cases. EuroScore-II differed significantly (medians 2.1 vs. 4.7, P<0.001). Propensity scores for choosing mini-parasternotomy were higher with lower EuroScore-II (OR=0.91 per 1%, P<0.001), aortic regurgitation (OR=2.3, P=0.005), and aortic non-mitral valve disease (OR=3.9, P<0.001). Adjusted for propensity score and EuroScore-II, mini-parasternotomy group had less pneumonia (OR=0.32, P=0.043), less sepsis (OR=0.31, P=0.045), and shorter non-complicated length of stay (coefficient=-7.2 (day), P<0.001) than full sternotomy group, whereas Kaplan-Meier survival, non-complicated ICU time, non-complicated ventilator time, and 30-day mortality did not differ significantly. CONCLUSION: The propensity-adjusted analysis demonstrated encouraging safety and quality outcomes for mini-parasternotomy valve operation in carefully selected patients.

Tuberculosis among newly arrived foreign spouses before obtaining citizenship, Taiwan, 2006-2011.

BACKGROUND: Taiwan's criterion for admissions of new immigrants is a normal chest X-ray (CXR). Subsequent tuberculosis (TB) screening for new foreign spouses is mandatory before acquiring citizenship. OBJECTIVES: To estimate the TB burden among new-entry foreign spouses and their close contacts. RESULTS: Of 768 new foreign spouses with TB, of whom 98.6% were female, 721 (94.0%) had come from South-East Asian countries (Viet Nam, Indonesia, Philippines and Thailand) or China. Rates of TB (40.3-176.2 per 100 000/year) among newly emigrant wives aged 20-49 years were 1.7- to 7.3-fold higher than among Taiwanese females of corresponding ages. TB prevalence among the 2698 close contacts of 768 foreign spouse index cases was 1.2%, according to a 2-year follow-up investigation. Respectively 87.9% (675/768) and 11.1% (85/768) of all TB cases had abnormal and normal CXRs; of these, 35.4% (239/675) of patients with an abnormal and 14.1% (12/85) of those with a normal CXR were smear-negative, culture-positive. CONCLUSIONS: Foreign wives from endemic countries had a relatively high risk of TB. Regular TB screening of foreign spouses within at least 1-2 years of entry from TB-endemic regions, rather than after application for citizenship, is recommended. A more sensitive TB test could facilitate better diagnosis.

Evidence for a role of oxidative stress in the carcinogenicity of ochratoxin a.

The in vitro and in vivo evidence compatible with a role for oxidative stress in OTA carcinogenicity has been collected and described. Several potential oxido-reduction mechanisms have been identified in the past. More recently, the possibility of a reduction of cellular antioxidant defense has been raised as an indirect source of oxidative stress. Consequences resulting from the production of oxidative stress are observed at different levels. First, OTA exposure has been associated with increased levels of oxidative DNA, lipid, and protein damage. Second, various biological processes known to be mobilized under oxidative stress were shown to be altered by OTA. These effects have been observed in both in vitro and in vivo test systems. In vivo, active doses were often within doses documented to induce renal tumors in rats. In conclusion, the evidence for the induction of an oxidative stress response resulting from OTA exposure can be considered strong. Because the contribution of the oxidative stress response in the development of cancers is well established, a role in OTA carcinogenicity is plausible. Altogether, the data reviewed above support the application of a threshold-based approach to establish safe level of dietary human exposure to OTA.

Analysis of 8 sarcomeric candidate genes for feline hypertrophic cardiomyopathy mutations in cats with hypertrophic cardiomyopathy.

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is the most common heart disease in cats. Causative mutations have been identified in the Maine Coon (MC) and Ragdoll breed in the cardiac myosin binding protein C gene (MYBPC3). HCM is thought to be inherited in other breeds. HYPOTHESIS: That a causative mutation for HCM in the British Shorthair (BSH), Norwegian Forest (NWF), Siberian, Sphynx, or MC cats would be identified in the exonic and splice site regions of 1 of 8 genes associated with human familial HCM. ANIMALS: Three affected BSH, NWF, Siberians, Sphynx, 2 MC (without the known MC mutation), and 2 Domestic Shorthair cats (controls) were studied. METHODS: Prospective, observational study. Exonic and splice site regions of the genes encoding the proteins cardiac troponin I, troponin T, MYBPC3, cardiac essential myosin light chain, cardiac regulatory myosin light chain, alpha tropomyosin, actin, and beta-myosin heavy chain were sequenced. Sequences were compared for nucleotide changes between affected cats, the published DNA sequences, and control cats. Changes were considered to be causative for HCM if they involved a conserved amino acid and changed the amino acid to a different polarity, acid-base status, or structure. RESULTS: A causative mutation for HCM was not identified, although several single nucleotide polymorphisms were detected. CONCLUSIONS AND CLINICAL IMPORTANCE: Mutations within these cardiac genes do not appear to be the only cause of HCM in these breeds. Evaluation of additional cardiac genes is warranted to identify additional molecular causes of this feline cardiac disease.

Induction of Nrf2-mediated cellular defenses and alteration of phase I activities as mechanisms of chemoprotective effects of coffee in the liver.

Coffee consumption has been associated with a significant decrease in the risk of developing chronic diseases such as Parkinson disease, diabetes type-2 and several types of cancers (e.g. colon, liver). In the present study, a coffee-dependent induction of enzymes involved in xenobiotic detoxification processes was observed in rat liver and primary hepatocytes. In addition, coffee was found to induce the mRNA and protein expression of enzymes involved in cellular antioxidant defenses. These inductions were correlated with the activation of the Nrf2 transcription factor as shown using an ARE-reporter luciferase assay. The induction of detoxifying enzymes GSTs and AKR is compatible with a protection against both genotoxicity and cytotoxicity of aflatoxin B1 (AFB1). This hypothesis was confirmed in in vitro and ex vivo test systems, where coffee reduced both AFB1-DNA and protein adducts. Interestingly, coffee was also found to inhibit cytochrome CYP1A1/2, indicating that other mechanisms different from a stimulation of detoxification may also play a significant role in the chemoprotective effects of coffee. Further investigations in either human liver cell line and primary hepatocytes indicated that the chemoprotective effects of coffee against AFB1 genotoxicity are likely to be of relevance for humans. These data strongly suggest that coffee may protect against the adverse effects of AFB1. In addition, the coffee-mediated stimulation of the Nrf2-ARE pathway resulting in increased endogenous defense mechanisms against electrophilic but also oxidative insults further support that coffee may be associated with a protection against various types of chemical stresses.

MAPK-ERK activation in kidney of male rats chronically fed ochratoxin A at a dose causing a significant incidence of renal carcinoma.

Kidney samples of male Fischer 344 (F-344) rats fed a carcinogenic dose of OTA over 7 days, 21 days and 12 months were analysed for various cell signalling proteins known to be potentially involved in chemical carcinogenicity. OTA was found to increase the phosphorylation of atypical-PKC. This was correlated with a selective downstream activation of the MAP-kinase extracellular regulated kinases isoforms 1 and 2 (ERK1/2) and of their substrates ELK1/2 and p90RSK. Moreover, analysis of effectors acting upstream of PKC indicated a possible mobilisation of the insulin-like growth factor-1 receptor (lGFr) and phosphoinositide-dependent kinase-1 (PDK1) system. An increased histone deacetylase (HDAC) enzymatic activity associated with enhanced HDAC3 protein expression was also observed. These findings are potentially relevant with respect to the understanding of OTA nephrocarcinogenicity. HDAC-induced gene silencing has previously been shown to play a role in tumour development. Furthermore, PKC and the MEK-ERK MAP-kinase pathways are known to play important roles in cell proliferation, cell survival, anti-apoptotic activity and renal cancer development.

A toxicogenomics approach to identify new plausible epigenetic mechanisms of ochratoxin a carcinogenicity in rat.

Ochratoxin A (OTA) is a mycotoxin occurring naturally in a wide range of food commodities. In animals, it has been shown to cause a variety of adverse effects, nephrocarcinogenicity being the most prominent. Because of its high toxic potency and the continuous exposure of the human population, OTA has raised public health concerns. There is significant debate on how to use the rat carcinogenicity data to assess the potential risk to humans. In this context, the question of the mechanism of action of OTA appears of key importance and was studied through the application of a toxicogenomics approach. Male Fischer rats were fed OTA for up to 2 years. Renal tumors were discovered during the last 6 months of the study. The total tumor incidence reached 25% at the end of the study. Gene expression profile was analyzed in groups of animals taken in intervals from 7 days to 12 months. Tissue-specific responses were observed in kidney versus liver. For selected genes, microarray data were confirmed at both mRNA and protein levels. In kidney, several genes known as markers of kidney injury and cell regeneration were significantly modulated by OTA. The expression of genes known to be involved in DNA synthesis and repair, or genes induced as a result of DNA damage, was only marginally modulated. Very little or no effect was found amongst genes associated with apoptosis. Alterations of gene expression indicating effects on calcium homeostasis and a disruption of pathways regulated by the transcription factors hepatocyte nuclear factor 4 alpha (HNF4alpha) and nuclear factor-erythroid 2-related factor 2 (Nrf2) were observed in the kidney but not in the liver. Previous data have suggested that a reduction in HNF4alpha may be associated with nephrocarcinogenicity. Many Nrf2-regulated genes are involved in chemical detoxication and antioxidant defense. The depletion of these genes is likely to impair the defense potential of the cells, resulting in chronic elevation of oxidative stress in the kidney. The inhibition of defense mechanism appears as a highly plausible new mechanism, which could contribute to OTA carcinogenicity.

The physiology of ileo-anal pouch function.

Even excellent clinical function after ileo-anal pouch construction is associated with a variety of physiological abnormalities. Small bowel intestinal motility is essentially normal but the ileal reservoir serves to markedly suppress the ileal motor response both to progressive distension by intestinal contents and to transmitted myoelectrical complexes. As a result, the healthy pouch can accommodate a large volume of intestinal content before the rising baseline pressure and the appearance of large isolated contraction waves produce an urge to defecate. Evacuation in the normal pouch patient is rapid and highly efficient and is achieved by means of the Valsalva maneuver without any evidence of significant intestinal propulsion. External anal sphincter function is fully preserved but internal anal sphincter function is significantly impaired in the immediate postoperative period. Recovery occurs over the next 6 to 12 months but is often incomplete. Bacterial overgrowth in the pouch and prepouch ileum is almost universal and results in the premature deconjugation of primary bile salts and accumulation of secondary bile salts within the pouch. These produce morphologic changes in the ileal mucosa, and their excretion in pouch effluent gradually depletes the bile salt pool. Anerobic organisms also bind with vitamin B12 and the vitamin B12-intrinsic factor complex, resulting in subtle but measurable reductions in vitamin B12 levels in pouch patients. Finally, anerobic fermentation of mucus and undigested carbohydrate results in excessive quantities of short chain fatty acids within the pouch lumen. The clinical significance of these substances is unclear, but they may have an adverse action on both ileal mucosal and smooth muscle function. In essence, however, the pouch surgeon can maximize the likelihood of good clinical function by constructing a large capacity pouch, by avoiding surgery in patients with clearly deficient anal sphincter mechanisms, and by careful attention to pouch-anal anastomotic technique.

Detection and rapid differentiation of human enteroviruses following genomic amplification.

By employing a nested PCR (n-PCR) with specific primers derived from the 5' nontranslated and consensus region of the human enterovirus genome, we detected enterovirus RNA from 32 different serotypes of prototypic strains. A specific 297-bp fragment was amplified by this method from all of these strains. Not only was the method highly sensitive, detecting enterovirus RNA extracted from 0.01 50% tissue culture infective dose/50 microl (which is more sensitive than our current routine method of enterovirus diagnosis, based on the virus isolation and serotypic neutralization), but it was also relatively rapid. By using this technology, we also detected enterovirus RNA in uncultured specimens (including throat swabs and stools) from patients with respiratory illness and acute flaccid paralysis syndrome. This method enabled us to rapidly and directly distinguish enterovirus-infected specimens from nonenterovirus specimens in laboratory diagnosis. Furthermore, restriction fragment length polymorphism was assessed as an alternative means of differentiating various serotypes of prototypical enteroviruses. Fourteen of 16 human enterovirus-infected specimens exhibited restriction patterns identical to those of the corresponding prototypes.

Identification of a measles virus isolate from a recent outbreak in northern Taiwan.

Specimens were collected during a recent outbreak. Those specimens displaying both CPE positive in B95-8 lymphocyte cell culture and positive by IFA were checked by a RT-PCR with a specific set of measles virus primers derived from the C-terminal of the nucleoprotein. Such RT-PCR method was found ideal for routine diagnostic purposes. Product from this RT-PCR was treated for plasmid construction before transformed into E. coli. One of those transformed clones, i. e. T94, was further studied for its DNA sequence. Since T94 is found to bear several evident different characteristics from those ever published, we conclude that this isolate is neither a vaccine derived strain nor one of those reported previously with specific amino acid residues, but unique in its own right. This isolate can well be a local lineage of wild measles virus in Taiwan.

[Neonatal hearing screening].

Auditory deprivation in early life significantly effects speech, language, cognition and learning development. The importance of neonatal hearing screening in order to detect and manage children with hearing impairment during the critical period before three years of age can't be neglected. The neonatal hearing screening program at Veterans General Hospital, Taipei, under a cooperation of audiologists, otologists and pediatricians, identified 1885 neonates for hearing loss from September 1990 to August 1991. There were two study groups, a high risk group of hearing impairment and a non-high risk group. We performed hearing screening and followed-up for the failure at initial test using methods including behavioral observation audiometry, auditory brainstem response, tympanogram, pneumatic otoscopy and questionnaire. Approximately 2.7% of neonates were classified as high risk for hearing loss, the incidence of hearing loss was 8% to 14% in this group. The incidence of hearing loss in non-high risk group was 0.11%. If both groups were contained that the incidence of hearing loss was 0.32% to 0.48%, 0.11% with a sensorineural hearing loss, 0.21% to 0.37% with a conductive hearing loss. Both behavioral audiometry (89% false negative rate) and questionnaire (50% return rate) were not effective for screening purposes in this study. Our results also indicated that the most advantage of using a high risk register lay in the fact that only 2.7% of a total population needed to be screened to identify approximately 67% to 78% of hearing-impaired babies. This saved both time and money.