Chronic binge drinking-induced susceptibility to colonic inflammation is microbiome-dependent.

Alterations in intestinal permeability and the gut microbiome caused by alcohol abuse are associated with alcoholic liver disease and with worsening of inflammatory bowel diseases (IBD) symptoms. To resolve the direct effects of chronic ethanol consumption on the colon and its microbiome in the absence of acute or chronic alcohol-induced liver disease, we developed a mouse model of chronic binge drinking that uncovers how alcohol may enhance susceptibility to colitis via the microbiota. Employing daily ethanol gavage, we recapitulate key features of binge ethanol consumption. We found that binge ethanol drinking worsens intestinal infection, colonic injury and inflammation, and this effect persists beyond the drinking period. Using gnotobiotics, we showed that alcohol-driven susceptibility to colitis is microbiota-dependent and transferable to ethanol-naïve mice by microbiome transplantation. Allobaculum spp. expanded in binge drinking mice, and administration of Allobaculum fili was sufficient to enhance colitis in non-drinking mice. Our study provides a model to study binge drinking-microbiota interactions and their effects on host disease and reinforces the pathogenic function of Allobaculum spp. as colitogenic bacteria. Our findings illustrate how chronic binge drinking-induced alterations of the microbiome may affect susceptibility to IBD onset or flares.

Delivery of minoxidil encapsulated in cyclodextrins with photoacoustic waves enhances hair growth.

The current pharmacological management of androgenetic alopecia is inconvenient and requires a discipline that patients find difficult to follow. This reduces compliance with treatment and satisfaction with results. It is important to propose treatment regimens that increase patient compliance and reduce adverse effects. This work describes transdermal delivery of minoxidil partially encapsulated in ß-cyclodextrin and assisted by photoacoustic waves. Photoacoustic waves transiently increase the permeability of the skin and allow for the delivery of encapsulated minoxidil. A minoxidil gel formulation was developed and the transdermal delivery was studied in vitro in the presence and absence of photoacoustic waves. A 5-min stimulus with photoacoustic waves generated by light-to-pressure transducers increases minoxidil transdermal delivery flux by approximately 3-fold. The flux of a 1% minoxidil formulation promoted by photoacoustic waves is similar to the passive flux of a 2% minoxidil commercial formulation. Release of minoxidil from ß-cyclodextrin increases dermal exposure without increasing peak systemic exposure. This promotes hair growth with fewer treatments and reduced adverse effects. In vivo studies using encapsulated minoxidil and photoacoustic waves yielded 86% hair coat recovery (vs. 29% in the control group) and no changes in the blood pressure.

Global Distribution of Canine Visceral Leishmaniasis and the Role of the Dog in the Epidemiology of the Disease.

Visceral leishmaniasis is a disease caused by protozoa of the species Leishmania (Leishmania) infantum (syn = Leishmania chagasi) and Leishmania (Leishmania) donovani, which are transmitted by hematophagous insects of the genera Lutzomyia and Phlebotomus. The domestic dog (Canis familiaris) is considered the main urban reservoir of the parasite due to the high parasite load on its skin, serving as a source of infection for sandfly vectors and, consequently, perpetuating the disease in the urban environment. Some factors are considered important in the perpetuation and spread of canine visceral leishmaniasis (CVL) in urban areas, such as stray dogs, with their errant behavior, and houses that have backyards with trees, shade, and organic materials, creating an attractive environment for sandfly vectors. CVL is found in approximately 50 countries, with the number of infected dogs reaching millions. However, due to the difficulty of controlling and diagnosing the disease, the number of infected animals could be even greater. In the four continents endemic for CVL, there are reports of disease expansion in endemic countries such as Brazil, Italy, Morocco, and Tunisia, as well as in areas where CVL is not endemic, for example, Uruguay. Socio-environmental factors, such as migration, drought, deforestation, and global warming, have been pointed out as reasons for the expansion into areas where it had been absent. Thus, the objective of this review is to address (i) the distribution of CVL in endemic areas, (ii) the role of the dog in the visceral leishmaniasis epidemiology and the factors that influence dog infection and the spread of the disease, and (iii) the challenges faced in the control of CVL.

New Approaches to the Prevention of Visceral Leishmaniasis: A Review of Recent Patents of Potential Candidates for a Chimeric Protein Vaccine.

The development of prophylactic vaccines is important in preventing and controlling diseases such as visceral leishmaniasis (VL), in addition to being an economic measure for public health. Despite the efforts to develop a vaccine against human VL caused by Leishmania infantum, none is available, and the focus has shifted to developing vaccines against canine visceral leishmaniasis (CVL). Currently, commercially available vaccines are targeted at CVL but are not effective. Different strategies have been applied in developing and improving vaccines, such as using chimeric proteins to expand vaccine coverage. The search for patents can be a way of tracking vaccines that have the potential to be marketed. In this context, the present work presents a summary of immunological aspects relevant to VL vaccine development with a focus on the composition of chimeric protein vaccines for CVL deposited in patent banks as an important approach for biotechnological development. The resulting data could facilitate the screening and selection of antigens to compose vaccine candidates with high performance against VL.

Secure Aggregation Protocol Based on DC-Nets and Secret Sharing for Decentralized Federated Learning.

In the era of big data, millions and millions of data are generated every second by different types of devices. Training machine-learning models with these data has become increasingly common. However, the data used for training are often sensitive and may contain information such as medical, banking, or consumer records, for example. These data can cause problems in people's lives if they are leaked and also incur sanctions for companies that leak personal information for any reason. In this context, Federated Learning emerges as a solution to the privacy of personal data. However, even when only the gradients of the local models are shared with the central server, some attacks can reconstruct user data, allowing a malicious server to violate the FL principle, which is to ensure the privacy of local data. We propose a secure aggregation protocol for Decentralized Federated Learning, which does not require a central server to orchestrate the aggregation process. To achieve this, we combined a Multi-Secret-Sharing scheme with a Dining Cryptographers Network. We validate the proposed protocol in simulations using the MNIST handwritten digits dataset. This protocol achieves results comparable to Federated Learning with the FedAvg protocol while adding a layer of privacy to the models. Furthermore, it obtains a timing performance that does not significantly affect the total training time, unlike protocols that use Homomorphic Encryption.

Amitriptyline ecotoxicity in Danio rerio (Hamilton, 1822) embryos - similar toxicity profile in the presence of nanoplastics.

Interaction of nanoplastics (NPls) with other environmental contaminants could affect their uptake by the organisms and their toxicity. Thus, the present study aims to investigate the polystyrene NPls (44 nm) interaction with the antidepressant amitriptyline (AMI) and its toxicity to Danio rerio embryos. A similar toxicological profile for NPls + AMI exposure was found for most of the evaluated endpoints, comparing with AMI single exposure, showing that the presence of NPls did not modulate the AMI toxicity. However, the behavioral assessment showed a different pattern with hypoactivity for the NPls + AMI exposure (NPls - hyperactivity; AMI - no effect). Interaction effects between NPls and AMI were also found in the protein contents (antagonism) and in the total glutathione content (synergism). This study highlights the complexity and unpredictability of NPls interaction with pharmaceuticals, important for an accurate environmental risk assessment and for the developing of effective strategies and interventions against plastic pollution.

Transmission-Blocking Vaccines for Canine Visceral Leishmaniasis: New Progress and Yet New Challenges.

Dogs with visceral leishmaniasis play a key role in the transmission cycle of Leishmania infantum to humans in the urban environment. There is a consensus regarding the importance of developing a vaccine to control this disease. Despite many efforts to develop a protective vaccine against CVL, the ones currently available, Leish-tec® and LetiFend®, have limited effectiveness. This is due, in part, to the complexity of the immune response of the naturally infected dogs against the parasite and the complexity of the parasite transmission cycle. Thus, strategies, such as the development of a transmission-blocking vaccines (TBVs) already being applied to other vector-borne diseases like malaria and dengue, would be an attractive alternative to control leishmaniasis. TBVs induce the production of antibodies in the vertebrate host, which can inhibit parasite development in the vector and/or interfere with aspects of vector biology, leading to an interruption of parasite transmission. To date, there are few TBV studies for CVL and other leishmaniasis forms. However, the few studies that exist show promising results, thus justifying the further development of this approach.

Photodynamic therapy changes tumour immunogenicity and promotes immune-checkpoint blockade response, particularly when combined with micromechanical priming.

Photodynamic therapy (PDT) with redaporfin stimulates colon carcinoma (CT26), breast (4T1) and melanoma (B16F10) cells to display high levels of CD80 molecules on their surfaces. CD80 overexpression amplifies immunogenicity because it increases same cell (cis) CD80:PD-L1 interactions, which (i) disrupt binding of T-cells PD-1 inhibitory receptors with their ligands (PD-L1) in tumour cells, and (ii) inhibit CTLA-4 inhibitory receptors binding to CD80 in tumour cells. In some cancer cells, redaporfin-PDT also increases CTLA-4 and PD-L1 expressions and virtuous combinations between PDT and immune-checkpoint blockers (ICB) depend on CD80/PD-L1 or CD80/CTLA-4 tumour overexpression ratios post-PDT. This was confirmed using anti-CTLA-4 + PDT combinations to increase survival of mice bearing CT26 tumours, and to regress lung metastases observed with bioluminescence in mice with orthotopic 4T1 tumours. However, the primary 4T1 responded poorly to treatments. Photoacoustic imaging revealed low infiltration of redaporfin in the tumour. Priming the primary tumour with high-intensity (~ 60 bar) photoacoustic waves generated with nanosecond-pulsed lasers and light-to-pressure transducers improved the response of 4T1 tumours to PDT. Penetration-resistant tumours require a combination of approaches to respond to treatments: tumour priming to facilitate drug infiltration, PDT for a strong local effect and a change in immunogenicity, and immunotherapy for a systemic effect.

The crosstalk between Stroke and Cancer: Incidence of cancer after a first-ever cerebrovascular event in a population-based study.

OBJECTIVES: To determine the cancer incidence after the first-ever cerebrovascular event (CVE) and compare it to the cancer incidence in the population from the same region. METHODS: We evaluated 1069 patients with a first-ever CVE (Ischaemic or haemorrhagic stroke and Transient Ischaemic Attack) from a prospective population registry of stroke and transient focal neurological attacks, diagnosed between 2009 and 2011. We conducted a structured search to identify cancer-related variables and case-fatality for a period of 8 years following CVE. Cancer incidence in CVE patients was compared to the North Region Cancer Registry (RORENO). RESULTS: We found that 90/1069 (8.4%) CVE patients developed cancer after a first-ever CVE. Overall cancer annual incidence rate was higher after a CVE (820/100,000, 95%CI: 619-1020) than in general population (513/100,000, 95%CI: 508-518). In the 45-54 age group cancer incidence post-CVE was 3.2-fold (RR, 95%CI: 1.6-6.4) higher compared to the general population, decreasing gradually in older age-groups. Median time between CVE and cancer was 3.2 years (IQR = 1.4-5.2). Lower respiratory tract and colorectal were the most frequent cancer types. In univariable models, male sex (sHR = 1.78, 95%CI: 1.17-2.72, p = 0.007), tobacco use (sHR = 2.04, 95%CI: 1.31-3.18, p = 0.002) and peripheral artery disease (sHR = 2.37, 95%CI: 1.10-5.13, p = 0.028) were associated to higher cancer risk after CVE. After adjustment, tobacco use (sHR = 1.84, 95%CI: 1.08-3.14, p = 0.026) remained associated to a higher risk of cancer. CONCLUSIONS: At the population level, patients presenting a first-ever CVE have higher cancer incidence, that is particularly prominent in younger age-groups. Higher cancer incidence, delayed cancer diagnosis and increased mortality post-CVE warrants further research on long-term cancer surveillance in first-ever CVE survivors.

Machine learning as an adjunct to expert observation in classification of radiographic knee osteoarthritis: findings from the Hertfordshire Cohort Study.

BACKGROUND: Osteoarthritis is the most prevalent type of arthritis. Many approaches exist for characterising radiographic knee OA, including machine learning (ML). AIMS: To examine Kellgren and Lawrence (K&L) scores from ML and expert observation, minimum joint space and osteophyte in relation to pain and function. METHODS: Participants from the Hertfordshire Cohort Study, comprising individuals born in Hertfordshire from 1931 to 1939, were analysed. Radiographs were assessed by clinicians and ML (convolutional neural networks) for K&L scoring. Medial minimum joint space and osteophyte area were ascertained using the knee OA computer-aided diagnosis (KOACAD) program. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) was administered. Receiver operating characteristic analysis was implemented for minimum joint space, osteophyte, and observer- and ML-derived K&L scores in relation to pain (WOMAC pain score > 0) and impaired function (WOMAC function score > 0). RESULTS: 359 participants (aged 71-80) were analysed. Among both sexes, discriminative capacity regarding pain and function was fairly high for observer-derived K&L scores [area under curve (AUC): 0.65 (95% CI 0.57, 0.72) to 0.70 (0.63, 0.77)]; results were similar among women for ML-derived K&L scores. Discriminative capacity was moderate among men for minimum joint space in relation to pain [0.60 (0.51, 0.67)] and function [0.62 (0.54, 0.69)]. AUC < 0.60 for other sex-specific associations. DISCUSSION: Observer-derived K&L scores had higher discriminative capacity regarding pain and function compared to minimum joint space and osteophyte. Among women, discriminative capacity was similar for observer- and ML-derived K&L scores. CONCLUSION: ML as an adjunct to expert observation for K&L scoring may be beneficial due to the efficiency and objectivity of ML.

Current and Advanced Applications of Gadoxetic Acid-enhanced MRI in Hepatobiliary Disorders.

Gadoxetic acid is an MRI contrast agent that has specific applications in the study of hepatobiliary disease. After being distributed in the vascular and extravascular spaces during the dynamic phase, gadoxetic acid is progressively taken up by hepatocytes and excreted to the bile ducts during the hepatobiliary phase. The information derived from the enhancement characteristics during dynamic and hepatobiliary phases is particularly relevant in the detection and characterization of focal liver lesions and in the evaluation of the structure and function of the liver and biliary system. The use of new MRI sequences and advanced imaging techniques (eg, relaxometry, multiparametric imaging, and analysis of heterogeneity), the introduction of artificial intelligence, and the development of biomarkers and radiomic and radiogenomic tools based on gadoxetic acid-enhanced MRI findings will play an important role in the future in assessing liver function, chronic liver disease, and focal liver lesions; in studying biliary pathologic conditions; and in predicting treatment responses and prognosis. © RSNA, 2023 Quiz questions for this article are available in the supplemental material.

A Review of Major Patents on Potential Malaria Vaccine Targets.

Malaria is a parasitic infection that is a great public health concern and is responsible for high mortality rates worldwide. Different strategies have been employed to improve disease control, demonstrating the ineffectiveness of controlling vectors, and parasite resistance to antimalarial drugs requires the development of an effective preventive vaccine. There are countless challenges to the development of such a vaccine directly related to the parasite's complex life cycle. After more than four decades of basic research and clinical trials, the World Health Organization (WHO) has recommended the pre-erythrocytic Plasmodium falciparum (RTS, S) malaria vaccine for widespread use among children living in malaria-endemic areas. However, there is a consensus that major improvements are needed to develop a vaccine with a greater epidemiological impact in endemic areas. This review discusses novel strategies for malaria vaccine design taking the target stages within the parasite cycle into account. The design of the multi-component vaccine shows considerable potential, especially as it involves transmission-blocking vaccines (TBVs) that eliminate the parasite's replication towards sporozoite stage parasites during a blood meal of female anopheline mosquitoes. Significant improvements have been made but additional efforts to achieve an efficient vaccine are required to improve control measures. Different strategies have been employed, thus demonstrating the ineffectiveness in controlling vectors, and parasite resistance to antimalarial drugs requires the development of a preventive vaccine. Despite having a vaccine in an advanced stage of development, such as the RTS, S malaria vaccine, the search for an effective vaccine against malaria is far from over. This review discusses novel strategies for malaria vaccine design taking into account the target stages within the parasite's life cycle.

Characterization of a late-onset multiple sclerosis Portuguese cohort.

BACKGROUND: Late-onset multiple sclerosis (LOMS) is defined as the onset of symptoms above 50 years, corresponding to an increasingly recognized subset of MS. This study aimed at comparing demographic and clinical data of patients with LOMS to those of early-onset MS (EOMS) from a Portuguese cohort. METHODS: Retrospective chart review of an MS cohort from a Portuguese tertiary center. RESULTS: From 746 patients with MS (61.7% female), we identified 39 cases with presentation after 50 years of age (22 males and 17 females), corresponding to 5.3%. The mean age at onset was 55.4 (±5.0) for LOMS and 29.5 (±8.9) for EOMS. There was no significant difference in disease duration. The most common type was relapsing-remitting MS, accounting for 51.5% and 83.9% of LOMS and EOMS patients, respectively. Primary-progressive MS (PPMS) was significantly more represented in the LOMS group (41.0%) (p < 0.01). The median EDSS was significantly higher in the LOMS group (4.75, 0.0-7.5) when compared to the EOMS group (2.0, 0.0-9,0). The most frequent presenting feature was myelitis in both LOMS (48.7%) and EOMS patients (47.4%), resulting in significantly higher EDSS (p = 0.003). CONCLUSIONS: LOMS is associated with higher EDSS when considering the same disease duration, translating into increased disability.

Predictors of cognitive dysfunction one-year post COVID-19.

OBJECTIVES: (a) To characterize the frequency of objective cognitive deficits and self-perceived cognitive difficulties and (b) to explore demographic and clinical predictors of cognitive dysfunction and cognitive complaints. METHOD: One hundred and ten adults diagnosed with COVID-19 between March and November 2020, aged ≤ 74 years underwent a brief neuropsychological evaluation 12 months after infection, which included: Brief Visuospatial Memory Test-Revised, California Verbal Learning Test, and Symbol Digit Modalities Test. T scores < 38 were considered abnormal performance; cognitive dysfunction was defined as ≥ 2 abnormal tests. Participants also completed Broadbent's Cognitive Failure Questionnaires (CFQ), Hospital Anxiety and Depression Scale, Modified Fatigue Impact Scale, and Short-Form Health Survey. CFQ ≥ 43 was considered indicative of cognitive complaints. RESULTS: Twenty participants (18.2%) had cognitive dysfunction and 36 (33.3%) had cognitive complaints. Cognitive dysfunction was related to lower education, preinfection history of headache/migraine, and acute COVID-19 symptoms of headache and sleep disturbance. Cognitive complaints were more likely to occur in women, those with fewer years of education, and acute COVID-19 symptoms of headache and sleep disturbance. Cognitive complaints were also significantly related to symptoms of anxiety, depression, and fatigue. Sex and psychopathology were not significant predictors of cognitive dysfunction. Modest associations were found between CFQ total score and cognitive test performance. DISCUSSION: A subset of individuals develops cognitive difficulties in the context of post-COVID syndrome. Results may support the protective effect of education, a known proxy of cognitive reserve. COVID-19 infection symptoms of headache and sleep disturbance appear to be risk factors for long-term cognitive difficulties. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Ex-situ magnetic activated carbon for the adsorption of three pharmaceuticals with distinct physicochemical properties from real wastewater.

Pharmaceuticals are able to evade conventional wastewater treatments and therefore, are recurrently found in the environment with proven potential to cause harm to human and wildlife. Adsorption onto activated carbon (AC) is a promising complement. However, AC production from non-renewable resources and its difficult after-use recuperation are prohibitive. Hence, a waste-based magnetic activated carbon (MAC) was produced from paper mill sludge, via an ex-situ synthesis, for the adsorptive removal of carbamazepine (CBZ), sulfamethoxazole (SMX) and ibuprofen (IBU) from ultrapure water and wastewater. The MAC was obtained through the promotion of electrostatic interactions between magnetic and activated carbon particles in a water suspension at controlled pH between the points of zero charge of both surfaces. The optimized condition (MACX3) presented remarkable properties regarding specific surface area (SBET=795 m2 g-1) and saturation magnetization (MS=19 emu g-1). Kinetic and equilibrium adsorption studies were performed under batch conditions. Adsorption equilibrium was reached in up to 30 min for all pharmaceuticals in both matrices, proving the low dependence on the adsorbate and the broad applicability of MACX3 in pharmaceutical adsorption. Regarding equilibrium experiments, high Langmuir maximum adsorption capacities (qm) were achieved in ultrapure water (up to 711 ± 40 µmol g-1). Equilibrium studies in wastewater revealed a decay in qm when compared to ultrapure water: 28% for CBZ (468 ± 20 µmol g-1 (111 ± 5 mg g-1)), 78% for SMX (145 ± 10 µmol g-1 (37 ± 3 mg g-1)) and 62% for IBU (273 ± 8 µmol g-1 (56 ± 2 mg g-1)), attributed to the wastewater pH, which dictates the speciation of the pharmaceuticals and controls electrostatic interactions between pharmaceuticals and MAC, and to competition effects by organic matter. It was demonstrated the promising applicability of a waste-based ex-situ MAC, rapidly retrievable from water, as an alternative tertiary wastewater treatment for pharmaceuticals removal.

Neoadjuvant chemotherapy for muscle-invasive bladder cancer: does variant histology matter?

PURPOSE: The most frequent histology of bladder tumors is urothelial carcinoma. Most are pure urothelial carcinomas (PUC) but up to one-third of the cases present variant histological (VH) features. The aim of this study was to evaluate the role of variant histology in neoadjuvant chemotherapy (NAC) response in patients with urothelial muscle-invasive bladder cancer. METHODS: We retrospectively analyzed data from 77 patients with bladder cancer who performed neoadjuvant chemotherapy at two institutions. RESULTS: Complete pathological response (ypT0) was higher in patients with PUC (38.5%), comparing with VH (12%). Logistic regression analysis demonstrated that variant histology is associated with an 89% lesser likelihood of tumor downstaging, with advanced clinical T stages and positive smoking history as independent predictors. The estimated mean cancer-specific survival was 68.91 months for PUC patients and 50.23 months for VH patients (log rank test, P = 0.024). Multivariate Cox regression analysis demonstrated that VH and clinical T stage were independent predictors of cancer-specific survival, indicating a worse outcome for patients with VH and advanced clinical T stages. CONCLUSIONS: There are only a few retrospective studies evaluating the clinical impact of variant histology tumors, which are mainly managed as PUC. Our results demonstrate that VH is associated with a worse likelihood of tumor downstaging after NAC and a worse cancer-specific survival in bladder cancer patients. There is a need for further studies and genetic analysis to identify the patients most likely to achieve ypT0 status and downstaging after NAC.

Colorectal cancer: the facts in the case of the microbiota.

The importance of the microbiota in the development of colorectal cancer (CRC) is increasingly evident, but identifying specific microbial features that influence CRC initiation and progression remains a central task for investigators. Studies determining the microbial mechanisms that directly contribute to CRC development or progression are revealing bacterial factors such as toxins that contribute to colorectal carcinogenesis. However, even when investigators have identified bacteria that express toxins, questions remain about the host determinants of a toxin's cancer-potentiating effects. For other cancer-correlating bacteria that lack toxins, the challenge is to define cancer-relevant virulence factors. Herein, we evaluate three CRC-correlating bacteria, colibactin-producing Escherichia coli, enterotoxigenic Bacteroides fragilis, and Fusobacterium nucleatum, for their virulence features relevant to CRC. We also consider the beneficial bioactivity of gut microbes by highlighting a microbial metabolite that may enhance CRC antitumor immunity. In doing so, we aim to elucidate unique and shared mechanisms underlying the microbiota's contributions to CRC and to accelerate investigation from target validation to CRC therapeutic discovery.

Rhipicephalus microplus: An overview of vaccine antigens against the cattle tick.

Rhipicephalus microplus, popularly known as the cattle tick, is the most important tick of livestock as it is responsible for significant economic losses. The use of chemical acaricides is still the most widely used control method despite its known disadvantages. Vaccination would be a safe alternative for the control of R. microplus and holds advantages over the use of chemical acaricides as it is environmental-friendly and leaves no residues in meat or milk. Two vaccines based on the Bm86 protein were commercialized, TickGARD® and Gavac®, with varying reported efficacies in different countries. The use of other vaccines, such as Tick Vac®, Go-Tick®, and Bovimune Ixovac® have been restricted to some countries. Several other proteins have been analyzed as possible antigens for more effective vaccines against R. microplus, including peptidases, serine proteinase inhibitors, glutathione S-transferases, metalloproteases, and ribosomal proteins, with efficacies ranging from 14% to 96%. Nonetheless, more research is needed to develop safe and efficient tick vaccines, such as the evaluation of the efficacy of antigens against other tick species to verify cross-reactivity and inclusion of additional antigens to promote the blocking of the infection and spreading of tick-borne diseases. This review summarizes the discoveries of candidate antigens for R. microplus tick vaccines as well as the methods used to test their efficacy.