Investigation of Mannheimia haemolytica bacteriophages relative to host diversity

Aims

This study aimed to characterize the impact of lytic and temperate bacteriophages on the genetic and phenotypic diversity of Mannheimia haemolytica from feedlot cattle.

Methods and Results

Strictly lytic phages were not detected from bovine nasopharyngeal (n = 689) or water trough (n = 30) samples, but Myoviridae‐ or Siphoviridae‐like phages were induced from 54 of 72 M. haemolytica strains by mitomycin C, occasionally from the same strain. Phages with similar restriction fragment length polymorphism profiles (RFLP ≥70% relatedness) shared common host serotypes 1 or 2 (P < 0·000 1). Likewise, phages with similar RFLP tended to occur in genetically related host bacteria (70–79% similarity). Host range assays showed that seven phages from host serotypes 1, 2 and 6 lysed representative strains of serotypes 1, 2 or 8. The genome of vB_MhM_1152AP from serotype 6 was found to be collinear with P2‐like phage φMhaA1‐PHL101.

Conclusions

Prophages are a significant component of the genome of M. haemolytica and contribute significantly to host diversity. Further characterization of the role of prophage in virulence and persistence of M. haemolytica in cattle could provide insight into approaches to control this potential respiratory pathogen.

Significance and Impact of the Study

This study demonstrated that prophages are widespread within the genome of M. haemolytica isolates and emphasized the challenge of isolating lytic phage as a therapeutic against this pathogen.     

Biochanin A improves fibre fermentation by cellulolytic bacteria

Aims

The objective was to determine the effect of the isoflavone biochanin A (BCA) on rumen cellulolytic bacteria and consequent fermentative activity.

Methods and Results

When bovine microbial rumen cell suspensions (n = 3) were incubated (24 h, 39°C) with ground hay, cellulolytic bacteria proliferated, short‐chain fatty acids were produced and pH declined. BCA (30 μg ml^?1) had no effect on the number of cellulolytic bacteria or pH, but increased acetate, propionate and total SCFA production. Addition of BCA improved total digestibility when cell suspensions (n = 3) were incubated (48 h, 39°C) with ground hay, Avicel, or filter paper. Fibrobacter succinogenes S85, Ruminococcus flavefaciens 8 and Ruminococcus albus 8 were directly inhibited by BCA. Synergistic antimicrobial activity was observed with BCA and heat killed cultures of cellulolytic bacteria, but the effects were species dependent.

Conclusions

These results indicate that BCA improves fibre degradation by influencing cellulolytic bacteria competition and guild composition.

Significance and Impact of the Study

BCA could serve as a feed additive to improve cellulosis when cattle are consuming high‐fibre diets. Future research is needed to evaluate the effect of BCA on fibre degradation and utilization in vivo.     

Herd prevalence of Enterobacteriaceae producing CTX‐M‐type and CMY‐2 β‐lactamases among Japanese dairy farms

Aims

To determine the herd prevalence of Enterobacteriaceae producing CTX‐M‐type extended‐spectrum β‐lactamases (ESBLs) among 381 dairy farms in Japan.

Methods and Results

Between 2007 and 2009, we screened 897 faecal samples using BTB lactose agar plates containing cefotaxime (2 μg ml^?1). Positive isolates were tested using ESBL confirmatory tests, PCR and sequencing for CTX‐M, AmpC, TEM and SHV. The incidence of Enterobacteriaceae producing CTX‐M‐15 (n = 7), CTX‐M‐2 (n = 12), CTX‐M‐14 (n = 3), CMY‐2 (n = 2) or CTX‐M‐15/2/14 and CMY‐2 (n = 4) in bovine faeces was 28/897 (3·1%) faecal samples. These genes had spread to Escherichia coli (n = 23) and three genera of Enterobacteriaceae (n = 5). Herd prevalence was found to be 20/381 (5·2%) dairy farms. The 23 E. coli isolates showed clonal diversity, as assessed by multilocus sequence typing and pulsed‐field gel electrophoresis. The pandemic E. coli strain ST131 producing CTX‐M‐15 or CTX‐M‐27 was not detected.

Conclusions

Three clusters of CTX‐M (CTX‐M‐15, CTX‐M‐2, CTX‐M‐14) had spread among Japanese dairy farms.

Significance and Impact of the Study

This is the first report on the prevalence of multidrug‐resistant CTX‐M‐15–producing E. coli among Japanese dairy farms.     

Fate of Escherichia coli O145 present naturally in bovine slurry applied to vegetables before harvest,after washing and simulated wholesale and retail distribution

Aims

To determine the fate of Escherichia coli on vegetables that were processed through commercial wash treatments and stored under simulated retail conditions at 4°C or wholesale at fluctuating ambient temperatures (0–25°C, dependent on season).

Methods and Results

Bovine slurry that was naturally contaminated with E. coli O145 was applied without dilution or diluted 1:10 using borehole water to growing potatoes, leeks or carrots. Manure was applied 1 week prior to harvest to simulate a near‐harvest contamination event by manure deposition or an application of contaminated water to simulate a flooding event or irrigation from a contaminated water source. At harvest, crops were contaminated at up to 2 log cfu g^?1. Washing transferred E. coli into the water of a flotation tank used for potato washing and did not completely remove all traces of contamination from the crop. Manure‐contaminated potatoes were observed to contain 0·72 cfu E. coli O145 g^?1 after processing and retail storage. Manure‐contaminated leeks harboured 0·73–1·55 cfu E. coli O145 g^?1 after washing and storage. There was no cross‐contamination when leeks were spray washed. Washing in an abrasive drum resulted in less than perfect decontamination for manure‐contaminated carrots. There were five post‐distribution isolations from carrots irrigated with contaminated water 24 h prior to harvest.

Conclusions

Standard commercial washing and distribution conditions may be insufficient to reliably control human pathogenic E. coli on fresh produce.

Significance and Impact

Previous speculation that the cause of a UK foodborne disease outbreak was soil from imperfectly cleaned vegetables is plausible.     

Brief report: Lactobacillus bulgaricus GLB44 (Proviotic™) plus esomeprazole for Helicobacter pylori eradication: A pilot study

Background

Recent studies of Lactobacillus delbrueckii subsp. bulgaricus GLB44 plus a proton‐pump inhibitor (PPI) reported cures of more than 90% of patients with active Helicobacter pylori infections.

Aim

To confirm the high H. pylori cure rates reported previously.

Method

A pilot study was done in healthy H. pylori‐infected volunteers using 3‐gram sachet (3 billion cells) of L. delbrueckii GLB44 plus 22.3 mg of esomeprazole b.i.d., for 14 days. The result was determined by urea breath testing 4 weeks after therapy. Stopping rules required for ending enrollment if less than 3 of the first 10 subjects were cured.

Results

Nine subjects were entered and because all failed to achieve negative urea breath test, the stopping rule required the study to end.

Conclusion

We were unable to confirm reports of achieving a high H. pylori cure rate with L. delbrueckii GLB44 plus a PPI.     

Anti‐Helicobacter pylori therapy in localized gastric mucosa‐associated lymphoid tissue lymphoma: A prospective,nationwide, multicenter study in Japan

Background

Helicobacter pylori eradication therapy was approved in Japan for the first‐line, standard treatment of H. pylori‐positive gastric mucosa‐associated lymphoid tissue (MALT) lymphoma. Although several retrospective studies or small‐scale single‐center studies have been reported, a prospective, large‐scale, nationwide, multicenter study has not been reported from Japan.

Materials and Methods

We conducted a prospective, nationwide, multicenter study to evaluate the clinical efficacy of rabeprazole‐based triple H. pylori eradication therapy for patients with localized gastric MALT lymphoma in practice‐based clinical trial. A total of 108 H. pylori‐positive patients with stage I/II₁ gastric MALT lymphoma underwent H. pylori eradication therapy. The primary endpoints were complete remission (CR) rate and the rate of transfer to secondary treatment. The secondary endpoints were CR maintenance duration and overall survival (OS).

Results

CR of lymphoma was achieved in 84 of 97 patients (86.6%), during the period 2.0‐44.7 months (median, 5.3 months) after starting H. pylori eradication treatment. CR was maintained in 77 of 81 patients (95.1%) for 0.4‐53.2 months (median, 33.1 months). Secondary treatments (radiotherapy, rituximab, or gastrectomy) for gastric MALT lymphoma were needed in 10 of the 97 patients (10.31%). During follow‐up, OS rate was 96.9% (94/97) and the causes of 3 deaths were not related to lymphoma.

Conclusions

Rabeprazole‐based H. pylori eradication therapy demonstrated a high CR rate, long CR maintenance, and a good OS for patients with localized gastric MALT lymphoma in this prospective, practice‐based, multicenter study.     

Beneficial effect of Burdock complex on asymptomatic Helicobacter pylori‐infected subjects: A randomized,double‐blind placebo‐controlled clinical trial

Background

Burdock complex (BC) constitutes of burdock (Arctium lappa), angelica (Angelica sinensis), gromwell (Lithospermum erythrorhizon), and sesame (Sesamum indicum) oil, which are commonly used in traditional Chinese medicine (TCM) for treating various disorders. This study intended to examine the anti‐H. pylori activity of BC on AGS cell model as well as in asymptomatic H. pylori‐infected subjects.

Materials and Methods

AGS cell incubated with H. pylori and treated with BC to evaluate the minimum inhibition concentration (MIC), cell viability (MTT) anti‐adhesion activity, and inflammatory markers. In case of clinical trial, H. pylori‐positive subjects (urea breath test [UBT] >10%, n = 36) were enrolled and requested to intake BC (n = 19) or placebo (n = 17) for 8 weeks. Antioxidant capacity, total phenol, UBT, inflammatory markers were analyzed at the initial, 4th, 8th, and 10th weeks. Moreover, the endoscopic examination was carried out on baseline and 10th week.

Results

In vitro studies showed that BC treatment significantly inhibited (P < .05) the inflammatory markers and adhesion of H. pylori to AGS cell. However, H. pylori‐infected subject ingested with BC for 8 weeks significantly decreased (P < .05) the UBT value, inflammatory markers with improved antioxidant activity, and phenolic levels as compared to placebo. Also, consumption of BC considerably healed the ulcer wound.

Conclusion

Overall, the BC could attenuate H. pylori infection by inhibiting H. pylori adhesion and subsequent inflammatory response on the gastric epithelial cell (AGS) as well as clinically ameliorated UBT, antioxidant capacity, and alleviated inflammation to display its anti‐H. pylori activity.     

Prevalence of Helicobacter pylori among Alaskans: Factors associated with infection and comparison of urea breath test and anti‐Helicobacter pylori IgG antibodies

Background

Helicobacter pylori is one of the most common human infections in the world, and studies in Alaska Native people, as well as other Indigenous peoples, have shown a high prevalence of this gastric infection. This study was undertaken to determine the prevalence of H. pylori infection by urea breath test (UBT) and anti‐ H. pylori IgG among Alaskans living in four regions of the state and to identify factors associated with infection.

Methods

A convenience sample of persons > 6 months old living in five rural and one urban Alaskan community were recruited from 1996 to 1997. Participants were asked about factors possibly associated with infection. Sera were collected and tested for anti‐ H. pylori IgG antibodies; a UBT was administered to participants > 5 years old.

Results

We recruited 710 people of whom 571 (80%) were Alaska Native and 467 (66%) were from rural communities. Rural residents were more likely to be Alaska Native compared with urban residents (P < .001). Of the 710 people, 699 (98%) had a serum sample analyzed, and 634 (97%) persons > 5 years old had a UBT performed. H. pylori prevalence was 69% by UBT and 68% by anti‐ H. pylori IgG. Among those with a result for both tests, there was 94% concordance. Factors associated with H. pylori positivity were Alaska Native racial status, age ≥ 20 years, rural region of residence, living in a crowded home, and drinking water that was not piped or delivered.

Conclusions

Helicobacter pylori prevalence is high in Alaska, especially in Alaska Native persons and rural residents. Concordance between UBT and serology was also high in this group. Two socioeconomic factors, crowding and drinking water that was not piped or delivered, were found to be associated with H. pylori positivity.     

Effect of menstrual cycle phase and hormonal treatments on evaluation of tubal patency in baboons

Background

We evaluated whether menstrual cycle phase influences the assessment of tubal patency by hysterosalpingography (HSG) in baboons.

Methods

Retrospective analysis of baseline tubal patency studies and serum estradiol (E₂) and progesterone (P4) values obtained from female baboons used as models for development of non‐surgical permanent contraception in women. The main outcome measure was bilateral tubal patency (BTP) in relationship with estradiol level.

Results

Female baboons (n = 110) underwent a single (n = 81), two (n = 26), or three (n = 3) HSG examinations. In 33/142 (23%) HSG examinations, one or both tubes showed functional occlusion (FO). The median E₂ in studies with BTP (49 pg/mL) was significantly higher than in those studies with FO (32 pg/mL, P = .005). Among 18 animals with repeat examinations where serum E₂ changed from <60 to ≥ 60 pg/mL, 13 results changed from FO to BTP (P = .0001). No sets showed a change from BTP to FO with an increase in estradiol.

Conclusion

In baboons, functional occlusion of the fallopian tube is associated with low estradiol levels, supporting a role for estrogen‐mediated relaxation of the utero‐tubal junction.     

Evaluation of DNA extraction methods for Bacillus anthracis spores isolated from spiked food samples

Aims

Nine commercial DNA extraction kits were evaluated for the isolation of DNA from 10‐fold serial dilutions of Bacillus anthracis spores using quantitative real‐time PCR (qPCR). The three kits determined by qPCR to yield the most sensitive and consistent detection (Epicenter MasterPure Gram Positive; MoBio PowerFood; ABI PrepSeq) were subsequently tested for their ability to isolate DNA from trace amounts of B. anthracis spores (approx. 6·5 × 10¹ and 1·3 × 10² CFU in 25 ml or 50 g of food sample) spiked into complex food samples including apple juice, ham, whole milk and bagged salad and recovered with immunomagnetic separation (IMS).

Methods and Results

The MasterPure kit effectively and consistently isolated DNA from low amounts of B. anthracis spores captured from food samples. Detection was achieved from apple juice, ham, whole milk and bagged salad from as few as 65 ± 14, 68 ± 8, 66 ± 4 and 52 ± 16 CFU, respectively, and IMS samples were demonstrated to be free of PCR inhibitors.

Conclusions

Detection of B. anthracis spores isolated from food by IMS differs substantially between commercial DNA extraction kits; however, sensitive results can be obtained with the MasterPure Gram Positive kit.

Significance and Impact of the Study

The extraction protocol identified herein combined with IMS is novel for B. anthracis and allows detection of low levels of B. anthracis spores from contaminated food samples.     

Presence of virulence markers in environmental Vibrio vulnificus strains

Aims

This work aims to demonstrate the presence of several genes and factors associated with virulence in strains isolated from the environment at Pueblo Viejo Lagoon, State of Veracruz, Mexico.

Methods and Results

In this study, we investigated the production of V. vulnificus virulence factors, as cytolysin (haemolysin), RTX toxin, metalloprotease, siderophores, capsular polysaccharide, adhesion structures (like type IV pili), and polar and lateral flagella, involved in swimming and swarming (or, at least, the presence of genes encoding some of them) in 40 strains of V. vulnificus isolated from water and food. The results indicate that strains of environmental origin possess potential virulence characteristics.

Conclusions

Caution should be exercised when consuming raw shellfish (especially by those more susceptible risk groups).

Significance and Impact of the Study

This is the first work focused on the evaluation of V. vulnificus virulence factors in Mexico.     

Antibiotics resistance of Helicobacter pylori in children with upper gastrointestinal symptoms in Hangzhou,China

Background

The decreasing eradication rate of Helicobacter pylori is mainly because of the progressive increase in its resistance to antibiotics. Studies on antimicrobial susceptibility of H. pylori in children are limited. This study aimed to investigate the resistance rates and patterns of H. pylori strains isolated from children.

Materials and Methods

Gastric mucosa biopsy samples obtained from children who had undergone upper gastrointestinal endoscopy were cultured for H. pylori, and susceptibility to six antibiotics (clarithromycin, amoxicillin, gentamicin, furazolidone, metronidazole, and levofloxacin) was tested from 2012‐2014.

Results

A total of 545 H. pylori strains were isolated from 1390 children recruited. The total resistance rates of H. pylori to clarithromycin, metronidazole, and levofloxacin were 20.6%, 68.8%, and 9.0%, respectively. No resistance to amoxicillin, gentamicin, and furazolidone was detected. 56.1% strains were single resistance, 19.6% were resistant to more than one antibiotic, 16.7% for double resistance, and 2.9% for triple resistance in 413 strains against any antibiotic. And the H. pylori resistance rate increased significantly from 2012‐2014. There was no significant difference in the resistance rates to clarithromycin, metronidazole, and levofloxacin between different gender, age groups, and patients with peptic ulcer diseases or nonulcer diseases.

Conclusions

Antibiotic resistance was indicated in H. pylori strains isolated from children in Hangzhou, and it increased significantly during the 3 years. Our data strongly support current guidelines, which recommend antibiotic susceptibility tests prior to eradication therapy.     

The implementation of the consensus on the management of Helicobacter pylori and barriers to consensus

Background

A consensus on the management of Helicobacter pylori has been developed. We aimed to assess whether dissemination through continuing medical education (CME) could enhance the adoption of this consensus among clinicians and to explore potential barriers to acceptance.

Materials and methods

Four CME courses were held to disseminate the consensus. Adoption surveys were performed to evaluate participants’ behavior in the past and their commitment to adopt the consensus in future clinical practice after CME. The gaps and barriers to adoption were also surveyed.

Results

A total of 240 physicians had attended the CME courses and received surveys with the 22 statements/substatements of the consensus. Before CME, adoption was good in six, fair in ten, and poor in six. After CME, 21 statements had either an initial >90% adoption or improvement to good or fair (P < 0.001), but one still had poor even though it showed improvement (P = 0.02). Although commitment was good or fair after CME, there was a >20% gap between “commitment” and “no barrier” to adoption for 11 statements, ten of which had a main barrier of financial incentives. Among the statements with fair or poor commitment after CME, less commitment to adoption and more barriers related to financial incentives were pronounced in clinicians serving in regional/district hospitals or clinics compared to those serving in medical centers.

Conclusions

Continuing medical education may improve the adoption of the H. pylori consensus. The financial incentives were shown to be a main barrier to adoption of the consensus and should be improved.     

Multiplex real‐time PCR assays for detection of four seedborne spinach pathogens

Aims

To develop multiplex TaqMan real‐time PCR assays for detection of spinach seedborne pathogens that cause economically important diseases on spinach.

Methods and Results

Primers and probes were designed from conserved sequences of the internal transcribed spacer (for Peronospora farinosa f. sp. spinaciae and Stemphylium botryosum), the intergenic spacer (for Verticillium dahliae) and the elongation factor 1 alpha (for Cladosporium variabile) regions of DNA. The TaqMan assays were tested on DNA extracted from numerous isolates of the four target pathogens, as well as a wide range of nontarget, related fungi or oomycetes and numerous saprophytes commonly found on spinach seed. Multiplex real‐time PCR assays were evaluated by detecting two or three target pathogens simultaneously. Singular and multiplex real‐time PCR assays were also applied to DNA extracted from bulked seed and single spinach seed.

Conclusions

The real‐time PCR assays were species‐specific and sensitive. Singular or multiplex real‐time PCR assays could detect target pathogens from both bulked seed samples as well as single spinach seed.

Significance and Impact of the Study

The freeze‐blotter assay that is currently routinely used in the spinach seed industry to detect and quantify three fungal seedborne pathogens of spinach (C. variabile, S. botryosum and V. dahliae) is quite laborious and takes several weeks to process. The real‐time PCR assays developed in this study are more sensitive and can be completed in a single day. As the assays can be applied easily for routine seed inspections, these tools could be very useful to the spinach seed industry.     

Para‐psychobiotic Lactobacillus gasseri CP2305 ameliorates stress‐related symptoms and sleep quality

Aims

To confirm the stress‐relieving effects of heat‐inactivated, enteric‐colonizing Lactobacillus gasseri CP2305 (paraprobiotic CP2305) in medical students taking a cadaver dissection course.

Methods and Results

Healthy students (21 males and 11 females) took paraprobiotic CP2305 daily for 5 weeks during a cadaver dissection course. The General Health Questionnaire and the Pittsburgh Sleep Quality Index were employed to assess stress‐related somatic symptoms and sleep quality respectively. The aggravation of stress‐associated somatic symptoms was observed in female students (P = 0·029). Sleep quality was improved in the paraprobiotic CP2305 group (P = 0·038), particularly in men (P = 0·004). Among men, paraprobiotic CP2305 shortened sleep latency (P = 0·035) and increased sleep duration (P = 0·048). Diarrhoea‐like symptoms were also effectively controlled with CP2305 (P = 0·005) in men. Thus, we observed sex‐related differences in the effects of paraprobiotic CP2305. In addition, CP2305 affected the growth of faecal Bacteroides vulgatus and Dorea longicatena, which are involved in intestinal inflammation.

Conclusions

CP2305 is a potential paraprobiotic that regulates stress responses, and its beneficial effects may depend on specific cell component(s).

Significance and Impact of the Study

This study characterizes the effects of a stress‐relieving para‐psychobiotic in humans.     

Some orangutans acquire enamel defects at regular intervals,but not according to seasonal cycles

Objectives

Developmental defects of tooth enamel are associated with systemic physiological stress and have been linked to seasonal environmental factors such as rainfall, temperature, and fruit availability. Here, we evaluate whether linear enamel hypoplasia and accentuated perikymata occur with any cyclicity on lower canines and then whether cycles differ between Bornean and Sumatran orangutans.

Materials and Methods

Epoxy casts of lower canines from Pongo abelii (n = 14) and P. pygmaeus (n = 33) were evaluated for perikymata and dental enamel defects. Individual developmental sequences (IDSs) were generated for each canine, tracking the position of each defect in the context of continuous perikymata (time). Autocorrelation, a form of time-series statistical analysis was run for each canine to identify whether any cyclicity of defect expression was discernable.

Results

Autocorrelation revealed cycles of defect expression within canines, but no common cycle periodicities were identified between individuals of the same species or across species. P. pygmaeus averaged more linear enamel hypoplasia per year than P. abelli, but no other comparisons (number of defects, number of perikymata between defects, and autocorrelation analysis) revealed differences between the species.

Discussion

Although no common patterns of defect expression were identified within or between P. abelli and P. pygmaeus, the potential for autocorrelation analysis is promising for primatological and paleoanthropological studies of seasonal phenomena.

     

Phylogenomics and signature proteins for the alpha Proteobacteria and its main groups

Background  

Alpha proteobacteria are one of the largest and most extensively studied groups within bacteria. However, for these bacteria as a whole and for all of its major subgroups (viz.Rhizobiales, Rhodobacterales, Rhodospirillales, Rickettsiales, SphingomonadalesandCaulobacterales), very few or no distinctive molecular or biochemical characteristics are known.     

Effects of extracellular DNA and DNA‐binding protein on the development of a Streptococcus intermedius biofilm

Aims

The aim of this study was to clarify the effects of homologous and heterologous extracellular DNAs (eDNAs) and histone‐like DNA‐binding protein (HLP) on Streptococcus intermedius biofilm development and rigidity.

Methods and Results

Formed biofilm mass was measured with 0·1% crystal violet staining method and observed with a scanning electron microscope. The localizations of eDNA and extracellular HLP (eHLP) in formed biofilm were detected by staining with 7‐hydoxyl‐9H‐(1,3‐dichloro‐9,9‐dimethylacridin‐2‐one) and anti‐HLP antibody without fixation, respectively. DNase I treatment (200 U ml^?1) markedly decreased biofilm formation and cell density in biofilms. Colocalization of eHLP and eDNA in biofilm was confirmed. The addition of eDNA (up to 1 μg ml^?1) purified from Strep. intermedius, other Gram‐positive bacteria, Gram‐negative bacteria, or human KB cells into the Strep. intermedius culture increased the biofilm mass of all tested strains of Strep. intermedius, wild‐type, HLP‐downregulated strain and control strains. In contrast, the addition of eDNA (>1 μg ml^?1) decreased the biofilm mass of all Strep. intermedius strains.

Conclusions

These findings demonstrated that eDNA and eHLP play crucial roles in biofilm development and its rigidity.

Significance and Impact of the Study

eDNA‐ and HLP‐targeting strategies may be applicable to novel treatments for bacterial biofilm‐related infectious diseases.     

Applying the polio model to New Zealand: The contingent role of socioeconomic status in infectious disease mortality

Objectives

The traditional polio model depicts a positive relationship between the disease and socioeconomic status (SES), with higher SES associated with exposure to the poliovirus beyond infancy/early childhood and a higher mortality rate. This study uses occupation data from non-Māori New Zealand death registrations and the Census to assess evidence for differential mortality by SES during the polio epidemics of 1916, 1924–25, and 1936–37.

Materials and Methods

Polio deaths were classified by father's occupation using the Caversham Project scheme, which includes nine collapsible urban occupational strata and codes rural occupations separately. Evidence for differential mortality and differences in age at death between rural and urban areas and among urban occupational strata was assessed using nonparametric Mann–Whitney U, Kruskal–Wallis, Jonckheere-Terpstra, and chi-square tests.

Results

There was limited evidence of either differential mortality or differences in age at death among collapsed urban strata, mainly in 1924/25, only partially meeting the expectations of the traditional polio model. For 1916 only, the rural group had a higher proportion of deaths (χ² (1, n = 95) = 8.341, p = 0.0039, φ = 0.30)) and higher age at death (U = 828.00, p = 0.026, r = −0.23).

Discussion

These results suggest that rural New Zealand was more isolated from poliovirus infection prior to 1916, but thereafter rural and urban groups faced more similar exposure patterns and mortality—at least among non-Māori. The degree to which occupational categories reflect conditions of exposure requires further research.

     

Atopic dermatitis‐mitigating effects of new Lactobacillus strain,Lactobacillus sakei probio 65 isolated from Kimchi

Aims

Atopic dermatitis (AD) is an inflammatory skin disease. Probiotics have been reported to modulate immune responses and thus are now being suggested as potential treatments for allergies. In this study, we investigated the inhibitory effects of Lactobacillus sakei probio 65 isolated from Kimchi on artificially inducing AD in NC/Nga mice.

Methods and Results

Oral administration of viable or heat‐inactivated Lact. sakei probio 65 improved the condition of skin and reduced scratching frequency. Serum levels of IgE and cutaneous T‐cell‐attracting chemokine (CTACK) were significantly decreased by this therapy. Dead Lact. sakei probio 65 also decreased IL‐4 and IL‐6 serum concentrations. Moreover, both live and dead Lact. sakei probio 65 inhibited the expression of Thymus and activation‐regulated chemokine and CTACK in AD‐like skin lesions. The increased levels of Foxp3 expression in the lesional skin and ears were also suppressed by Lact. sakei probio 65. In addition, Lact. sakei probio 65 inhibited β‐hexosaminidase release and the secretion of IL‐4, TNF‐α and IL‐6 from RBL‐2H3 cells.

Conclusions

Oral treatment with both viable and heat‐inactivated Lact. sakei probio 65 inhibits skin inflammation and AD‐like skin lesions, as well as mast cell activation.

Significance and Impact of the Study

Lactobacillus sakei probio 65 has an inhibitory effect on atopic dermatitis‐like skin lesions and may represent an effective new anti‐inflammatory agent.