Clinical Features of Four Cases with Cashew Nut Allergy and Cross-Reactivity between Cashew Nut and Pistachio

BackgroundFew cases of cashew nut (CN) allergy have been reported in Japan. We evaluated the clinical features of 4 cases with CN allergy and investigated the allergens involved.MethodsIn order to investigate the cross-reactivity between CN and pistachios, we performed ImmunoCAP inhibition tests using sera of 4 cases with positive histories of CN allergy and positive results of specific IgE measurement (ImmunoCAP) and skin prick tests. Furthermore, we analyzed the molecular weights of allergens of CN and pistachios by IgE-immunoblotting.ResultsOf the 4 cases (male : female = 1 : 3), there were 3 cases (patient #2-4) and 1 case (patient #1) of anaphylaxis and oral allergy syndrome, respectively. The initial symptom was an oropharyngeal symptom in 3 of the 4 cases, of which 2 cases developed anaphylaxis within 10 minutes after eating only a few pieces of CN. All 4 cases reacted positively to the skin prick test with CN, although 1 case of anaphylaxis tested negatively for CN by ImmunoCAP. Additionally, in 2 cases, IgE-binding to CN and pistachio were inhibited with both pistachios and CN, indicating cross-reactivity between CN and pistachios. IgE-immunoblotting of CN using sera from the 4 cases revealed 2 bands at molecular weights of approximately 33 kd and 42 kd, whereas that of pistachios showed a single band at 36 kd. However, IgE in all 4 sera did not bind to rAna o 2.ConclusionsIn CN allergy, a small amount of CN could induce a severe anaphylactic reaction. Moreover, in cases of suspected CN allergy, reactions to not only CN but also pistachio, which could be cross-reactive to CN, should be examined.     

Allergic Reactions to Clopidogrel and Cross-Reactivity to Other Agents

Clopidogrel is a widely used antiplatelet agent, particularly after coronary stent implantation. About 1% of patients have allergic or hematologic adverse reactions to clopidogrel. This has important therapeutic implications, as premature discontinuation of clopidogrel is the strongest risk factor for stent thrombosis. Clopidogrel allergy most commonly manifests as a rash. It is important to distinguish this from other causes of rash occurring in patients who have had a recent coronary stent. Although antihistamines and short-term oral corticosteroids are effective in treating most clopidogrel hypersensitivity reactions, some persistent reactions may require discontinuation of clopidogrel. When discontinuation of clopidogrel is required, substitution with an alternative thienopyridine such as ticlopidine traditionally has been performed. However, a recent study suggests that there may be as high as a 27% risk of recurrence of non-life-threatening allergic reactions in such patients, which are usually similar to the allergic reactions that occurred with clopidogrel. No data are available regarding the frequency of cross-reactivity to prasugrel and ticagrelor; these may be potential therapeutic options in some patients.     

Classification of Food Allergens and Cross-Reactivity

Patients with specific food allergies are commonly sensitized to related foods, for example, shrimp with other shellfish and peanut with other legumes. In some instances, this represents a true allergy to the related food, defined as cross-reactivity, while in other instances, it represents a positive skin or IgE test only, in a patient who can eat the related food without difficulty. This is defined as cross-sensitization. It is extremely important that the clinician recognize these patterns of cross-sensitization and cross-reactivity, both to counsel patients on foods that should be avoided and to make sure that foods are not unnecessarily restricted from the diet. In fact, it is very common for patients to be instructed to avoid entire food groups based just on positive tests, which leads to unnecessary dietary restrictions with effects on food choices, nutrition, and quality of life.     

In vitro lymphocytic stimulation with PPD

One-way mixed lymphocyte reaction with PPD in healthy volunteers and in patients suffering from tuberculosis gave us no correlation with the degree of Mantoux sensitization. There were two major indications for further study: (a) An adequate stimulation index (SI) against PPD in vitro in tuberculosis patients correlated with satisfactory treatment results in a higher percentage than did a low stimulation index. (b) In patients, a lower PPD concentration seems to be needed for a stimulation index greater than one than in healthy individuals.     

Thrombocytopenia Associated with Hypersensitivity to Ranitidine: Possible Cross-Reactivity with Cimetidine

A rare case of thrombocytopenia associated with ranitidine is described. The thrombocytopenia was accompanied by eosinophilia and slightly elevated serum IgE. The platelet and eosinophilic counts returned to normal as soon as the drug was stopped. Cell-mediated immunity (CMI) determined in vitro by the leukocyte migration inhibition factor test was found against ranitidine and cimetidine. IgE antibody response against both drugs was also found by the mast cell degranulation test. These data suggest an association between the ranitidine-induced thrombocytopenia and both humoral antibody response and CMI. Cross-reactivity between the two H2-receptor antagonists is suggested, as well.     

Nuts and Cardiovascular Disease Prevention

Purpose of Review

We review recent epidemiological and clinical studies investigating the consumption of tree nuts and peanuts and cardiovascular disease (CVD) mortality as well as CVD risk factors.

Recent Findings

A greater consumption of tree nuts and peanuts is associated with a reduced risk of CVD mortality, as well as lower CVD events. Furthermore, risk factors associated with the development of CVD such as dyslipidemia, impaired vascular function, and hypertension are improved with regular tree nut and peanut consumption through a range of mechanism associated with their nutrient-rich profiles. There is weak inconsistent evidence for an effect of nut consumption on inflammation. There is emerging evidence that consuming tree nuts reduces the incidence of non-alcoholic fatty liver disease (NAFLD) and promotes diversity of gut microbiota, which in turn may improve CVD outcomes.

Summary

Evidence for CVD prevention is strong for some varieties of tree nuts, particularly walnuts, and length of supplementation and dose are important factors for consideration with recommendations.

     

In vitro studies with sisomicin, gentamicin and tobramycin

Sisomicin, gentamicin and tobramycin were tested in vitro against 25 isolates each of five genera of clinically significant gram-negative bacteria. Both minimal inhibitory concentrations and minimal bactericidal concentrations were determined using Mueller-Hinton broth and agar. In terms of inhibition, sisomicin was the most active drug against Enterobacter aerogenes, Klebsiella pneumoniae, Serratia marcescens and Proteus mirabilis, while tobramycin was the most active against Pseudomonas aeruginosa. In terms of bactericidal activity, sisomicin was the more active drug against E. aerogenes, K. pneumoniae and P. mirabilis, while gentamicin was the most active against S. marcescens and tobramycin the most active against P. aeruginosa.     

Quantifying T Cell Cross-Reactivity: Influenza and Coronaviruses

If viral strains are sufficiently similar in their immunodominant epitopes, then populations of cross-reactive T cells may be boosted by exposure to one strain and provide protection against infection by another at a later date. This type of pre-existing immunity may be important in the adaptive immune response to influenza and to coronaviruses. Patterns of recognition of epitopes by T cell clonotypes (a set of cells sharing the same T cell receptor) are represented as edges on a bipartite network. We describe different methods of constructing bipartite networks that exhibit cross-reactivity, and the dynamics of the T cell repertoire in conditions of homeostasis, infection and re-infection. Cross-reactivity may arise simply by chance, or because immunodominant epitopes of different strains are structurally similar. We introduce a circular space of epitopes, so that T cell cross-reactivity is a quantitative measure of the overlap between clonotypes that recognize similar (that is, close in epitope space) epitopes.     

Nuts and Berries for Heart Health

Nuts are nutrient-dense foods with complex matrices rich in unsaturated fatty acids and other bioactive compounds, such as L-arginine, fiber, minerals, tocopherols, phytosterols, and polyphenols. By virtue of their unique composition, nuts are likely to beneficially impact heart health. Epidemiologic studies have associated nut consumption with a reduced incidence of coronary heart disease in both genders and diabetes in women. Limited evidence also suggests beneficial effects on hypertension and inflammation. Interventional studies consistently show that nut intake has a cholesterol-lowering effect and there is emerging evidence of beneficial effects on oxidative stress, inflammation, and vascular reactivity. Blood pressure, visceral adiposity, and glycemic control also appear to be positively influenced by frequent nut consumption without evidence of undue weight gain. Berries are another plant food rich in bioactive phytochemicals, particularly flavonoids, for which there is increasing evidence of benefits on cardiometabolic risk that are linked to their potent antioxidant power.     

In vitro and In vivo Studies with Trasylol, an Anticoagulant and a Fibrinolytic Inhibitor

S ummary Trasylol is a competitive inhibitor of plasminogen activation by streptokinase and urokinase. The proteolytic activity of plasmin and trypsin is inhibited non-competitively and the esterolytic activity of urokinase is inhibited in a mixed competitive and non-competitive manner. These inhibitory effects are observed at high substrate concentrations. At low substrate concentrations, the inhibitory effects of Trasylol are relatively increascd. Trasylol is considerably more effective in vitro as an inhibitor of fibrinolytic activity than tranexamic acid and EACA: and in contrast to these amino acid inhibitors, Trasylol is more effective as an inhibitor of formed plasmin than of plasminogen activation.
Trasylol possesses anticoagulant effects probably due to inhibition of prothrombin conversion and of intrinsic thromboplastin formation.
Irt vivo in high dosage Trasylol imparts antifibrinolytic, anticoagulant and anti-tryptic effects to plasma. It may accelerate platelet aggregation in vivo .
In one patient with hypofibrinogenaemia, its administration was associated with a fall in the platelet count. In another patient there was evidence of a rise in fibrinogen Factor V, antihaeinophilic globulin (Factor VIII) and in the platelet count.
An initial dosage of 100,000 units as a single injection or as an infusion given over 1 hour followed by maintenance dosage of 50,000 units/hr. seems appropriate in the treatment of pathological fibrinolysis. For the therapy of intravascular coagulation, higher dosage may be required, possibly 100,000 units/hr. This latter dosage would also be required in the treatment of systemic proteolysis due to trypsin.     

In vitro tetraploidy in patients with ulcerative colitis

One hundred and seven patients (57 patients with ulcerative colitis and 50 controls) were investigated for in vitro tetraploidy (IVT) in dermal fibroblast monolayer cultures. There was no difference in incidence of IVT between patients with ulcerative colitis and controls. We advance the hypothesis that the genetic background of the colorectal cancer type found in ulcerative colitis differs from that found in the colon cancer syndromes and in non-hereditary colorectal cancers. Colorectal cancer in ulcerative colitis is probably only dependent on the degree of inflammatory lesions of the colonic mucosa.     

In vitro and In vivo Antimalarial Activity of Amphiphilic Naphthothiazolium Salts with Amine-Bearing Side Chains

Because of emerging resistance to existing drugs, new chemical classes of antimalarial drugs are urgently needed. We have rationally designed a library of compounds that were predicted to accumulate in the digestive vacuole and then decrystallize hemozoin by breaking the iron carboxylate bond in hemozoin. We report the synthesis of 16 naphthothiazolium salts with amine-bearing side chains and their activities against the erythrocytic stage of Plasmodium falciparum in vitro. KSWI-855, the compound with the highest efficacy against the asexual stages of P. falciparum in vitro, also had in vitro activity against P. falciparum gametocytes and in vivo activity against P. berghei in a murine malaria model.     

In vivo and in vitro drug metabolism in patients with leprosy

Plasma antipyrine and chloramphenicol clearance was studied in 23 patients of leprosy and 12 control subjects. Drug metabolising enzymes (aminopyrine N-demethylase and bilirubin UDP-glucuronyl transferase) were estimated in liver biopsy samples of twelve patients and ten controls. A significant decrease in drug clearance and drug metabolising enzymes was observed. However, no significant correlation could be obtained between drug half lives and drug metabolising enzymes or with any of the liver function tests in these patients. The findings indicate that drug metabolism is impaired in leprosy patients.     

In vitro selection with artificial expanded genetic information systems

Artificially expanded genetic information systems (AEGISs) are unnatural forms of DNA that increase the number of independently replicating nucleotide building blocks. To do this, AEGIS pairs are joined by different arrangements of hydrogen bond donor and acceptor groups, all while retaining their Watson–Crick geometries. We report here a unique case where AEGIS DNA has been used to execute a systematic evolution of ligands by exponential enrichment (SELEX) experiment. This AEGIS–SELEX was designed to create AEGIS oligonucleotides that bind to a line of breast cancer cells. AEGIS–SELEX delivered an AEGIS aptamer (ZAP-2012) built from six different kinds of nucleotides (the standard G, A, C, and T, and the AEGIS nonstandard P and Z nucleotides, the last having a nitro functionality not found in standard DNA). ZAP-2012 has a dissociation constant of 30 nM against these cells. The affinity is diminished or lost when Z or P (or both) is replaced by standard nucleotides and compares well with affinities of standard GACT aptamers selected against cell lines using standard SELEX. The success of AEGIS–SELEX relies on various innovations, including (i) the ability to synthesize GACTZP libraries, (ii) polymerases that PCR amplify GACTZP DNA with little loss of the AEGIS nonstandard nucleotides, and (iii) technologies to deep sequence GACTZP DNA survivors. These results take the next step toward expanding the power and utility of SELEX and offer an AEGIS–SELEX that could possibly generate receptors, ligands, and catalysts having sequence diversities nearer to that displayed by proteins.A quarter century ago, various laboratories independently sought to apply in vitro selection, commonly called “SELEX” (systematic evolution of ligands by exponential enrichment), to create DNA and RNA (collectively “xNA”) “aptamers”, xNA molecules that bind specifically to many different types of targets (1–3). SELEX follows a simple recipe that includes (i) making a library of nucleic acid molecules; (ii) placing the library in contact with the target to separate molecules in the library that bind from those that do not; (iii) amplifying “survivors” by PCR; and (iv) after a sufficient number of cycles of selection, recovering individual aptamers that are sequenced, resynthesized, and characterized as molecular entities having unambiguous molecular structures.SELEX has had substantial success, with xNA aptamers now known for many targets, including small molecules, carbohydrates, peptides, and various kinds of cancer cells (4–7). Nevertheless, considerable effort has been devoted to improving SELEX (8–10). Improvements were initially sought by adding functionalized side chains to one or more of the standard nucleotides used in the SELEX library (11–13). More recently, Perrin and coworkers have had notable success obtaining catalytic DNAzymes using heavily functionalized DNA libraries (14). Following a slightly different rationale, SomaLogic has obtained slow off-rate modified aptamers (SOMAmers) by appending hydrophobic side chains (e.g., benzyl, naphthyl, tryptamino, and isobutyl) to nucleobases (15). In one set of SOMAmers targeted against ∼800 different human proteins, affinities in the 0.1 pM–1 μM range are reported (16).However, another approach to increase the power of aptamers is to increase the number of independently replicating nucleotides in the xNA library. For example, Hirao and coworkers recently added a fifth nucleotide to aptamers against IFN-gamma and VEGF-165 (17). Adding nucleotides to xNA libraries offers the possibility of obtaining higher information density in aptamer sequences, a richer variety of folds, more control over folding interactions, and xNA libraries having sequences and functional diversity more like proteins.Another approach starts with the recognition that the two nucleobase pairs found in natural xNA [G:C and A:T(U)] do not exploit all possible hydrogen bonding patterns (Fig. 1). Therefore, rearranging hydrogen bond donor and acceptor groups on the nucleobases can increase the number of independently replicable nucleosides in xNA from 4 to 12 (forming six nucleobase pairs) (18). In this artificially expanded genetic information system (AEGIS), the 12 different nucleotide “letters” pair via six distinguishable hydrogen bonding patterns to give a system that can pair, be copied, and evolve like natural DNA, but with higher information density and more functional groups (19). This laid the grounds for the work reported here, an “AEGIS–SELEX.”Open in a separate windowFig. 1.(Left) Watson–Crick pairing follows two rules of complementarity: (i) size complementarity (large purines pair with small pyrimidines) and (ii) hydrogen bonding complementarity [hydrogen bond donors (blue) pair with hydrogen bond acceptors (red)]. Rearranging hydrogen bond donors and acceptors on the bases gives an artificially expanded genetic information system (AEGIS). An xNA biopolymer having functionalized AEGIS components may allow SELEX to yield protein-like aptamers better than the standard DNA and RNA biopolymers. The example of AEGIS–SELEX reported here adds the Z:P pair, shown at the bottom of the molecular structures. (Right) The images show the general idea behind AEGIS in cartoon form.We report here a unique example of AEGIS–SELEX. This AEGIS–SELEX exploits two additional nucleotides [2-amino-8-(1′-β-d-2-deoxyribofuranosyl)-imidazo[1,2-a]-1,3,5-triazin-4(8H)one, trivially called P, and 6-amino-5-nitro-3-(1′-β-d-2′-deoxyribofuranosyl)-2(1H)-pyridone, trivially called Z] (20–23). GACTZP AEGIS–SELEX is based on the following features of a molecular biology for “second generation” AEGIS that have been developed over the past few years in these laboratories:

• (i) Methods to synthesize libraries containing 10¹²–10¹⁴ different AEGIS oligonucleotides (20).
• (ii) Procedures to PCR amplify AEGIS nucleotides (22, 24).
• (iii) Procedures to sequence AEGIS DNA molecules that emerge after multiple rounds of selection (22).

In this AEGIS–SELEX effort, we chose an especially challenging target, a line of breast cancer cells (MDA-MB-231) (25). In addition to exploiting the latest whole-cell SELEX technology that has been developed with standard GACT SELEX, this target has considerable medical interest (26).