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1.
The “miracle” antibiotics and sulfa drugs have been found unsatisfactory in treating certain severe resistant urinary tract infections apparently due to lack of immunity factor in the patient. Of a series of 56 patients with resistant urinary tract infection who were treated with autogenous vaccine and then with sulfa drugs, 26 were completely cured.  相似文献   

2.
The immunity of a host population against specific influenza A strains can influence a number of important biological processes, from the emergence of new virus strains to the effectiveness of vaccination programmes. However, the development of an individual’s long-lived antibody response to influenza A over the course of a lifetime remains poorly understood. Accurately describing this immunological process requires a fundamental understanding of how the mechanisms of boosting and cross-reactivity respond to repeated infections. Establishing the contribution of such mechanisms to antibody titres remains challenging because the aggregate effect of immune responses over a lifetime are rarely observed directly. To uncover the aggregate effect of multiple influenza infections, we developed a mechanistic model capturing both past infections and subsequent antibody responses. We estimated parameters of the model using cross-sectional antibody titres to nine different strains spanning 40 years of circulation of influenza A(H3N2) in southern China. We found that “antigenic seniority” and quickly decaying cross-reactivity were important components of the immune response, suggesting that the order in which individuals were infected with influenza strains shaped observed neutralisation titres to a particular virus. We also obtained estimates of the frequency and age distribution of influenza infection, which indicate that although infections became less frequent as individuals progressed through childhood and young adulthood, they occurred at similar rates for individuals above age 30 y. By establishing what are likely to be important mechanisms driving epochal trends in population immunity, we also identified key directions for future studies. In particular, our results highlight the need for longitudinal samples that are tested against multiple historical strains. This could lead to a better understanding of how, over the course of a lifetime, fast, transient antibody dynamics combine with the longer-term immune responses considered here.  相似文献   

3.
Lessons learned from the vaccines against SARS‐CoV‐2 has encouraged research and vaccine development aimed at mustering strong T cell responses against the pathogen. Subject Categories: Microbiology, Virology & Host Pathogen Interaction, Pharmacology & Drug Discovery

The new vaccines against SARS‐CoV‐2 elicited strong antibody responses in initial trials, which encouraged optimism amongst immunologists and public health experts who expected good efficacy. “With viral infections, it is almost unheard of to have a prophylactic vaccine that doesn’t work ultimately by generating neutralising antibody responses”, explained immunologist Kingston Mills at Trinity College Dublin in Ireland. However, the antibody response is not the whole story. “Efforts to explain how immunity is working against viruses to the general public has forced everyone to try to make things so simple that now what is left is a ridiculous oversimplified picture of the vertebrate immune system”, commented Antonio Bertoletti, infectious disease scientist at Duke‐National University of Singapore. In fact, there is increasing research focus on the role of T cells in mediating the cellular response to infections and how to stimulate these cells through vaccines.Antibodies work by recognising and attaching to surface structures of a virus or bacterium, which prevents the pathogen from infecting its target cells and mark it for destruction by other immune cells. However, pathogens can escape the antibody response via mutations that decrease the efficiency of antibodies from infection or vaccination. “You will still potentially get infected if you’re vaccinated, because the antibody response is not as strong as it was”, explained immunologist Luke O’Neill at Trinity College Dublin, Ireland. “But then the T cells will kick in and stop the virus when it is inside cells”. Simply put, antibodies tend to prevent infection, while T cells combat infection and illness. Specifically, CD4 helper T cells primarily encourage B cells to generate antibodies whereas CD8 “killer” T cells eliminate cancerous and virally infected cells.  相似文献   

4.

Background

Generation of robust cell-mediated immune responses at mucosal surfaces while reducing overall inflammation is a primary goal for vaccination. Here we report the use of a recombinant nanoparticle as a vaccine delivery platform against mucosal infections requiring T cell-mediated immunity for eradication.

Methodology/Principal Findings

We encapsulated an immunogenic protein, the major outer membrane protein (MOMP) of Chlamydia muridarum, within hollow, vault nanocapsules (MOMP-vaults) that were engineered to bind IgG for enhanced immunity. Intranasal immunization (i.n) with MOMP-vaults induced anti-chlamydial immunity plus significantly attenuated bacterial burden following challenge infection. Vault immunization induced anti-chlamydial immune responses and inflammasome formation but did not activate toll-like receptors. Moreover, MOMP-vault immunization enhanced microbial eradication without the inflammation usually associated with adjuvants.

Conclusions/Significance

Vault nanoparticles containing immunogenic proteins delivered to the respiratory tract by the i.n. route can act as “smart adjuvants” for inducing protective immunity at distant mucosal surfaces while avoiding destructive inflammation.  相似文献   

5.
The rise of resistance together with the shortage of new broad-spectrum antibiotics underlines the urgency of optimizing the use of available drugs to minimize disease burden. Theoretical studies suggest that coordinating empirical usage of antibiotics in a hospital ward can contain the spread of resistance. However, theoretical and clinical studies came to different conclusions regarding the usefulness of rotating first-line therapy (cycling). Here, we performed a quantitative pathogen-specific meta-analysis of clinical studies comparing cycling to standard practice. We searched PubMed and Google Scholar and identified 46 clinical studies addressing the effect of cycling on nosocomial infections, of which 11 met our selection criteria. We employed a method for multivariate meta-analysis using incidence rates as endpoints and find that cycling reduced the incidence rate/1000 patient days of both total infections by 4.95 [9.43–0.48] and resistant infections by 7.2 [14.00–0.44]. This positive effect was observed in most pathogens despite a large variance between individual species. Our findings remain robust in uni- and multivariate metaregressions. We used theoretical models that reflect various infections and hospital settings to compare cycling to random assignment to different drugs (mixing). We make the realistic assumption that therapy is changed when first line treatment is ineffective, which we call “adjustable cycling/mixing”. In concordance with earlier theoretical studies, we find that in strict regimens, cycling is detrimental. However, in adjustable regimens single resistance is suppressed and cycling is successful in most settings. Both a meta-regression and our theoretical model indicate that “adjustable cycling” is especially useful to suppress emergence of multiple resistance. While our model predicts that cycling periods of one month perform well, we expect that too long cycling periods are detrimental. Our results suggest that “adjustable cycling” suppresses multiple resistance and warrants further investigations that allow comparing various diseases and hospital settings.  相似文献   

6.
Macrolides, a class of antimicrobials isolated from Streptomycetes more than 50 years ago, are used extensively to treat sinopulmonary infections in humans. In addition, a growing body of experimental and clinical evidence indicates that long-term (years), low (sub-antimicrobial)-dose 14- and 15-membered ring macrolide antibiotics, such as erythromycin, clarithromycin, roxithromycin and azithromycin, express immunomodulatory and tissue reparative effects that are distinct from their anti-infective properties. These salutary effects are operative in various lung disorders, including diffuse panbronchiolitis, cystic fibrosis, persistent chronic rhinosinusitis, nasal polyposis, bronchiectasis, asthma and cryptogenic organizing pneumonia.The purpose of this overview is to outline the immunomodulatory effects of macrolide antibiotics in patients with asthma.  相似文献   

7.
8.
Improving childhood vaccination coverage and timeliness is a key health policy objective in many developing countries such as Uganda. Of the many factors known to influence uptake of childhood immunizations in under resourced settings, parents’ understanding and perception of childhood immunizations has largely been overlooked. The aims of this study were to survey mothers’ knowledge and attitudes towards childhood immunizations and then determine if these variables correlate with the timely vaccination coverage of their children. From September to December 2013, we conducted a cross-sectional survey of 1,000 parous women in rural Sheema district in southwest Uganda. The survey collected socio-demographic data and knowledge and attitudes towards childhood immunizations. For the women with at least one child between the age of one month and five years who also had a vaccination card available for the child (N = 302), the vaccination status of this child was assessed. 88% of these children received age-appropriate, on-time immunizations. 93.5% of the women were able to state that childhood immunizations protect children from diseases. The women not able to point this out were significantly more likely to have an under-vaccinated child (PR 1.354: 95% CI 1.018–1.802). When asked why vaccination rates may be low in their community, the two most common responses were “fearful of side effects” and “ignorance/disinterest/laziness” (44% each). The factors influencing caregivers’ demand for childhood immunizations vary widely between, and also within, developing countries. Research that elucidates local knowledge and attitudes, like this study, allows for decisions and policy pertaining to vaccination programs to be more effective at improving child vaccination rates.  相似文献   

9.
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11.
The pathophysiologic mechanisms behind urologic disease are increasingly being elucidated. The object of this investigation was to evaluate the publication policies of urologic journals during a period of progressively better understanding and management of urologic disease. Based on the ISI Web of Knowledge Journal Citation Reports and the PubMed database, the number and percentage of original experimental, original clinical, review or commentarial articles published between 2002–2010 in six leading urologic journals were analyzed. “British Journal of Urology International”, “European Urology”, “Urologic Oncology-Seminars and Original Investigations” (“Urologic Oncology”), “Urology”, “The Journal of Urology”, and “World Journal of Urology” were chosen, because these journals publish articles in all four categories. The publication policies of the six journals were very heterogeneous during the time period from 2002 to 2010. The percentage of original experimental and original clinical articles, related to all categories, remained the same in “British Journal of Urology International”, “Urologic Oncology”, “Urology” and “The Journal of Urology”. The percentage of experimental reports in “World Journal of Urology” between 2002–2010 significantly increased from 10 to 20%. A distinct elevation in the percentage of commentarial articles accompanied by a reduction of clinical articles became evident in “European Urology” which significantly correlated with a large increase in the journal’s impact factor. No clearly superior policy could be identified with regard to a general increase in the impact factors from all the journals. The publication policy of urologic journals does not expressly reflect the increase in scientific knowledge, which has occurred over the period 2002–2010. One way of increasing the exposure of urologists to research and expand the interface between experimental and clinical research, would be to enlarge the percentage of experimental articles published. There is no indication that such policy would be detrimental to a journal’s impact factor.  相似文献   

12.

Background

A causal relationship between maternal obesity and offspring asthma is hypothesized to begin during early development, but no underlying mechanism for the found association is identified. We quantitatively examined mediation by offspring body mass index (BMI) in the association of maternal pre-pregnancy BMI on risk of asthma and wheezing during the first 7–8 years of life in a large Amsterdam born birth cohort.

Methods

For 3185 mother-child pairs, mothers reported maternal pre-pregnancy BMI and offspring outcomes “ever being diagnosed with asthma” and “wheezing in the past 12 months” on questionnaires. We measured offspring height and weight at age 5–6 years. We performed a multivariate log linear regression comparing outcomes in offspring of mothers with different BMI categories. For each category we quantified and tested mediation by offspring BMI and also investigated interaction by parental asthma.

Results

At the age of 7–8 years, 8% of the offspring ever had asthma and 7% had current wheezing. Maternal pre-pregnancy obesity was associated with higher risks of asthma (adjusted RR 2.32 (95% CI: 1.49–3.61) and wheezing (adjusted RR 2.16 (95% CI: 1.28–3.64). Offspring BMI was a mediator in the association between maternal BMI and offspring wheezing, but not for asthma. There was no interaction by parental asthma.

Conclusions

Maternal pre-pregnancy obesity was associated with higher risks of offspring asthma and wheezing. The association between maternal obesity and offspring wheezing was both direct and indirect (mediated) through the child’s own BMI.  相似文献   

13.
Soon after the occupation of Japan, military physicians began recording an unusually large number of patients with asthma. Subsequent reports labeled the condition “Yokohama asthma” and called it a new environmental respiratory disease. It occurred in the Tokyo-Yokohama area, in previously healthy persons, from October to May during the time of the heaviest concentration of air pollution.The disease begins with cough at night, wheezing and shortness of breath, and apparently does not respond to the usual forms of treatment for asthma. It was reported that the symptoms subsided upon removal of the patient from the Tokyo-Yokohama area but abruptly recurred upon return to the area. It has been implied that the disease is a hypersensitivity phenomenon due to some unknown contaminant in the atmosphere. More recent studies indicate that Tokyo-Yokohama asthma is not a disease but a syndrome seen in people with bronchial infections and asthma. The high level of air pollution is thought to have an aggravating rather than a sensitizing effect.  相似文献   

14.
International Journal of Peptide Research and Therapeutics - Pidotimod has been shown to exhibit immunomodulatory activities and exert protective effects against bacterial infections. This study...  相似文献   

15.
16.
This paper is the study of 144 girls with histories of urinary tract infection followed at the Stanford Medical Center who were found to be free of ureterovesical reflux. The mean age at onset of infection for the entire group was about four years and ranged from the first few months of life to age 10. Ninety-two percent of the 505 infection episodes in these children presented with symptoms referable to the lower tract, and bacterial localization studies confirmed that 85 percent of the infections were limited to the bladder. Escherichia coli was the most common organism isolated and most infections were caused by a pure culture of a single bacteria.In only two of the 144 patients studied was there any evidence of upper tract damage related to infection. The possibility that these patients had reflux at an earlier age could not be discounted.In response to short-term antibacterial therapy in 66 of the patients followed closely for an average of 40 months each, 20 percent of the patients had no further infections and 80 percent went on to recurrence. With each succeeding treatment an additional 20 percent of the patients were “cured,” but the remainder experienced recurrent infections during the follow-up. This reinfection pattern supports the use of long-term antibacterial prophylaxis in all girls who have more than three or four recurrences of infections. Urethral dilation appeared to have no value in reducing the reinfection rate. While it appears that in the absence of ureterovesical reflux few, if any, of these children will go on to develop upper tract damage, long-term prophylactic suppressive medication can clearly be justified on the grounds of reducing patient morbidity.  相似文献   

17.
A classification of asthma into allergic and nonallergic has gained support from the more recent studies on the underlying causes of the disease.The majority of instances of nonallergic asthma occur after middle life and result from recurrent infections of the upper and lower respiratory tract. Status asthmaticus is a frequent complication of infectious asthma.Chronic and intractable asthma may be present also in a patient with allergic asthma complicated by a superimposed infection of the sinuses, bronchi and lungs.There are many secondary or precipitating causes that may bring on asthmatic paroxysms. The most important of these are acute respiratory infections, mechanical and chemical irritants, autonomic imbalance, hormonal deficiencies and psychogenic influences. These secondary causes play a more important role in nonallergic asthma because of the greater tendency to chronicity in this form of the disease.The effective treatment of chronic asthma depends largely on the successful control of the secondary or precipitating causes of the asthmatic attacks.The introduction of the antibiotics and corticosteroids in the treatment of infectious asthma has supplied potent weapons to combat the disease. The use of these therapeutic agents makes possible the control of two of the important pathologic lesions of asthma—bronchial infection and bronchial inflammation.At present combined antibiotic and cortisone or hydrocortisone therapy of asthma seems to be the most rational method of preventing the disease from becoming chronic and intractable. Their value in infectious asthma is due to their anti-infective and antiflammatory action.When prolonged treatment is essential, combined therapy also lessens the dangers arising from the presence of masked infections.  相似文献   

18.
Sublingual route has been widely used to deliver small molecules into the bloodstream and to modulate the immune response at different sites. It has been shown to effectively induce humoral and cellular responses at systemic and mucosal sites, namely the lungs and urogenital tract. Sublingual vaccination can promote protection against infections at the lower and upper respiratory tract; it can also promote tolerance to allergens and ameliorate asthma symptoms. Modulation of lung’s immune response by sublingual immunotherapy (SLIT) is safer than direct administration of formulations by intranasal route because it does not require delivery of potentially harmful molecules directly into the airways. In contrast to intranasal delivery, side effects involving brain toxicity or facial paralysis are not promoted by SLIT. The immune mechanisms underlying SLIT remain elusive and its use for the treatment of acute lung infections has not yet been explored. Thus, development of appropriate animal models of SLIT is needed to further explore its potential advantages. This work shows how to perform sublingual administration of therapeutic agents in mice to evaluate their ability to protect against acute pneumococcal pneumonia. Technical aspects of mouse handling during sublingual inoculation, precise identification of sublingual mucosa, draining lymph nodes and isolation of tissues, bronchoalveolar lavage and lungs are illustrated. Protocols for single cell suspension preparation for FACS analysis are described in detail. Other downstream applications for the analysis of the immune response are discussed. Technical aspects of the preparation of Streptococcus pneumoniae inoculum and intranasal challenge of mice are also explained.SLIT is a simple technique that allows screening of candidate molecules to modulate lungs’ immune response. Parameters affecting the success of SLIT are related to molecular size, susceptibility to degradation and stability of highly concentrated formulations.  相似文献   

19.
Bordetella pertussis infection remains an important public health problem worldwide despite decades of routine vaccination. A key indicator of the impact of vaccination programmes is the inter-epidemic period, which is expected to increase with vaccine uptake if there is significant herd immunity. Based on empirical data from 64 countries across the five continents over the past 30–70 years, we document the observed relationship between the average inter-epidemic period, birth rate and vaccine coverage. We then use a mathematical model to explore the range of scenarios for duration of immunity and transmission resulting from repeat infections that are consistent with empirical evidence. Estimates of pertussis periodicity ranged between 2 and 4.6 years, with a strong association with susceptible recruitment rate, defined as birth rate × (1 − vaccine coverage). Periodicity increased by 1.27 years on average after the introduction of national vaccination programmes (95% CI: 1.13, 1.41 years), indicative of increased herd immunity. Mathematical models suggest that the observed patterns of pertussis periodicity are equally consistent with loss of immunity that is not as rapid as currently thought, or with negligible transmission generated by repeat infections. We conclude that both vaccine coverage and birth rate drive pertussis periodicity globally and that vaccination induces strong herd immunity effects. A better understanding of the role of repeat infections in pertussis transmission is critical to refine existing control strategies.  相似文献   

20.

Background

Diabetes Mellitus is a multifaceted chronic illness and its life-long treatment process requires patients to continuously engage with the healthcare system. The understanding of how patients manoeuvre through the healthcare system for treatment is crucial in assisting them to optimise their disease management. This study aims to explore issues determining patients’ treatment strategies and the process of patients manoeuvring through the current healthcare system in selecting their choice of treatment for T2DM.

Methods

The Grounded Theory methodology was used. Twelve patients with Type 2 Diabetes Mellitus, nine family members and five healthcare providers from the primary care clinics were interviewed using a semi-structured interview guide. Three focus group discussions were conducted among thirteen healthcare providers from public primary care clinics. Both purposive and theoretical samplings were used for data collection. The interviews were audio-taped and transcribed verbatim, followed by line-by-line coding and constant comparison to identify the categories and core category.

Results

The concept of “experimentation” was observed in patients’ help-seeking behaviour. The “experimentation” process required triggers, followed by information seeking related to treatment characteristics from trusted family members, friends and healthcare providers to enable decisions to be made on the choice of treatment modalities. The whole process was dynamic and iterative through interaction with the healthcare system. The decision-making process in choosing the types of treatment was complex with an element of trial-and-error. The anchor of this process was the desire to fulfil the patient’s expected outcome.

Conclusion

Patients with Type 2 Diabetes Mellitus continuously used “experimentation” in their treatment strategies and help-seeking process. The “experimentation” process was experiential, with continuous evaluation, information seeking and decision-making tinged with the element of trial-and-error. The theoretical model generated from this study is abstract, is believed to have a broad applicability to other diseases, may be applied at varying stages of disease development and is non-context specific.  相似文献   

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