Evaluation of Allergenicity of Constituents of Myoga Using the Murine Local Lymph Node Assay

Myoga ( Zingiber Myoga Roscoe) is a perennial plant with a pungent smell from its flower buds. It is native to East Asia and has been reported to cause allergic contact dermatitis. The purpose of this study is to assess the allergenicity of myoga related to its major chemical components, α-pinene, β-pinene, limonene, limonene oxide and β-phellandrene, which are supposed to be the causative agents of contact dermatitis among myoga cultivators. We performed a toxicity study of the volatile constituents of myoga using the local lymph node assay (LLNA), in which limonene, limonene oxide and β-phellandrene had positive responses and the EC3 was 35.8%, 8.22%, and 0.54%, respectively. EC3 for both α-pinene and β-pinene was over 100%. Both chemicals failed to induce positive responses in the LLNA. While the maximization rating of limonene, limonene oxide and phellandrene were evaluated as moderate, extreme, and extreme respectively, α-pinene and β-pinene were evaluated as weak in the previously reported GPMT. The usage of LLNA was also confirmed by comparing with previously reported GPMT results to detect the allergenicity of myoga constituents. The actual risk of humans developing an allergy to myoga constituents depends on many factors. The concentration of the compounds, the frequency and duration of exposure and the condition of the skin are supposed to be important factors.

In conclusion, limonene, limonene oxide and β-phellandrene are constituents of myoga which revealed their allergenicity by the LLNA. The usefulness of the LLNA to detect the allergenicity of myoga constituents was also confirmed when considering the differences between the LLNA in the present study and the previously reported GPMT. The actual risk of humans developing an allergy to myoga constituents depends on many factors. The concentration of the compounds, the frequency and duration of exposure and condition of the skin are all important factors.

Effects of bead size and polymerization in PMMA bone cement on vancomycin release

Polymethylmethacrylate (PMMA) bone cement loaded with antimicrobial agents is used for the treatment and prevention of infections in orthopaedic surgery. The use of antimicrobial-loaded bone cement allows for high local doses while avoiding systemic toxicity. The release of vancomycin (VCM) from bone cement has been reported. However, the exact mechanism behind the release is unknown. We studied the influence of bead size and polymerization time on elution, and considered the release mechanism for VCM. We used CMW Endurance Bone Cement. Cements were prepared by mixing 6 g of VCM with 40 g of polymer, and then 10 g of liquid monomer was added. We kneaded and shaped the preparation into spheres containing 10.7 w/w% VCM. We measured the release of VCM from PMMA beads of three different sizes. Average weights of the beads were 0.96 g (SB) (n = 6), 2.86 g (MB) (n = 2) and 5.65 g (LB) (n = 1). Additionally, we studied beads made with different polymerization times. The polymerization time was taken as the period from the making of the beads until the start of the study, and was 15 min (B15), 20 min (B20), 60 min (B60) or 180 min (B180). The release of VCM showed a bimodal curve with a high initial release followed by a sustained release. Regarding the size of the beads, SB released 7.2%, MB released 4.3% and LB released 3.1%. Regarding polymerization time, B15 released 10.0%, B20 released 6.5%, B60 released 6.3% and B180 released 4.3%, respectively. The release of VCM from PMMA beads was influenced by bead size and polymerization time. Those beads which were smaller and had a shorter polymerization time released more VCM. Total pore volume of beads that polymerization time was 30 min after drug-release test was 1.33 times grater than that of control beads that polymerization time was one week before drug-release test. This suggested that the short polymerization time caused the beads to leak more VCM. We proposed a model with four kinds of the dissolution from bone cement. (A) Dissolution from drug particles on the cement surface. This type shows the burst effect of release curve. (B) Dissolution from micropores near the cement surface. It is responsible the grater part of the curve based on Higuchi's equation. (C) Dissolution from ink-bottle-neck-type micropores. It causes a release based on a non-Higuchi's equation. (D) No dissolution from Encapsulation micropores.It can be concluded that the release of VCM from bone cements is controlled by a combination of surface area and polymerization time. PMMA beads loaded with VCM should be used carefully in orthopaedic surgery, taking into consideration the influence of bead size and polymerization time.

Higher heart rate may predispose to obesity and diabetes mellitus: 20-year prospective study in a general population

BACKGROUND

Emerging evidence indicates an association between sympathetic activation and metabolic syndrome. However, sympathetic activation in metabolic syndrome may be a cause, consequence, or just epiphenomenon. To elucidate this issue, the predictive power of resting heart rate for the development of abnormal glucose and lipid metabolisms after 20 years was evaluated in a general population.

METHODS

A total of 637 participants (>20 years old) underwent a health examination in 1979 including measurements of blood chemistries. Resting heart rate (bpm) was measured by an electrocardiogram. In 1999, all of the study participants again underwent a health examination, including electrocardiogram and blood chemistries. Because four of them had atrial fibrillation, and 19 subjects were taking antihypertensive medication in 1979, they were excluded from analysis. Therefore, a complete dataset of 614 subjects was available.

RESULTS

As was reported in our previous article, in 1999 we found a linear and significant (P < 0.05) cross-sectional relationship between resting heart rate and a cluster of cardiometabolic risk factors (blood pressure (BP), free fatty acid (FFA), plasma glucose, and homeostasis model assessment (HOMA) index). Baseline higher heart rate (heart rate >or=80 bpm in 1979) predicted the development of obesity, diabetes mellitus (DM), and insulin resistance in 1999 after adjustments for age, sex, and other confounders.

CONCLUSION

This is one of the first prospective reports demonstrating that higher heart rate may predispose to the development of obesity and DM, suggesting that the sympathetic nerve system may play a role in the development of obesity and DM.

Dual source coronary computed tomography angiography for detecting in-stent restenosis

OBJECTIVE

To evaluate the performance of dual source CT coronary angiography (DSCT-CA) in the detection of in-stent restenosis (>or=50% luminal narrowing) in symptomatic patients referred for conventional angiography (CA). DESIGN/ PATIENTS: 100 patients (78 males, age 62 (SD 10)) with chest pain were prospectively evaluated after coronary stenting. DSCT-CA was performed before CA.

SETTING

Many patients undergo coronary artery stenting; availability of a non-invasive modality to detect in-stent restenosis would be desirable.

RESULTS

Average heart rate (HR) was 67 (SD 12) (range 46-106) bpm. There were 178 stented lesions. The interval between stenting and inclusion in the study was 35 (SD 41) (range 3-140) months. 39/100 (39%) patients had angiographically proven restenosis. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of DSCT-CA, calculated in all stents, were 94%, 92%, 77% and 98%, respectively. Diagnostic performance at HR <70 bpm (n = 69; mean 58 bpm) was similar to that at HR >or=70 bpm (n = 31; mean 78 bpm); diagnostic performance in single stents (n = 95) was similar to that in overlapping stents and bifurcations (n = 83). In stents >or=3.5 mm (n = 78), sensitivity, specificity, PPV, NPV were 100%; in 3 mm stents (n = 59), sensitivity and NPV were 100%, specificity 97%, PPV 91%; in stents <or=2.75 mm (n = 41), sensitivity was 84%, specificity 64%, PPV 52%, NPV 90%. Nine stents <or=2.75 mm were uninterpretable. Specificity of DSCT-CA in stents >or=3.5 mm was significantly higher than in stents <or=2.75 mm (OR = 6.14; 99%CI: 1.52 to 9.79).

CONCLUSION

DSCT-CA performs well in the detection of in-stent restenosis. Although DSCT-CA leads to frequent false positive findings in smaller stents (<or=2.75 mm), it reliably rules out in-stent restenosis irrespective of stent size.

Role of substance P as a sensory transmitter in spinal cord and sympathetic ganglia

The hypothesis that substance P (SP) might be a transmitter of primary sensory neurons was first proposed by Lembeck in 1953. A large amount of evidence supporting this hypothesis has recently accumulated, particularly since the elucidation of the chemical structure of SP by Leeman and her colleagues in 1971, which made a number of new approaches possible (e.g. radioimmunoassay for SP, immunohistochemistry and electrophysiological tests of SP action on central and peripheral neurons). SP is concentrated in certain primary afferent terminals in the spinal cord, is released therefrom when the dorsal roots are electrically stimulated, and exerts a powerful excitant action on spinal neurons. It is therefore likely that SP produces excitatory postsynaptic potentials (EPSPs) in spinal neurons, although the characteristics of SP-mediated EPSPs, i.e. their time course, ionic mechanisms, etc., remain to be revealed. Recent electrophysiological and neurochemical studies on the prevertebral ganglia of the guinea-pig strongly suggest that SP is released from axon collaterals of visceral primary afferent neurons in the ganglia and serves as a transmitter that generates non-cholinergic slow EPSPs in principal cells. There is evidence that this SP-mediated synaptic transmission in the sympathetic ganglia is under the influence of enkephalinergic presynaptic inhibition. Some preliminary experiments on the interaction between SP and enkephalins in the spinal cord are described.

Poor postoperative blood glucose control increases surgical site infections after surgery for hepato-biliary-pancreatic cancer: a prospective study in a high-volume institute in Japan

Two hundred and sixty-five consecutive patients awaiting hepato-biliary-pancreatic surgery were prospectively observed for surgical site infections (SSIs). SSI rates differed according to type of hepato-biliary-pancreatic surgery. Multivariate analysis identified enteric anastomoses, poor postoperative blood glucose control and type of cancer as independent risk factors. SSI rates were directly correlated with the degree of hyperglycaemia encountered during the postoperative period. In particular, SSI rates were 5/25 (20%) among patients in whom a blood glucose level of <200mg/dL was maintained by insulin infusion therapy, which was significantly better than the rates of 49/94 (52%) among patients in whom a blood glucose level of <200mg/dL was not maintained despite insulin infusion therapy (P<0.01). It is necessary to maintain postoperative blood glucose levels of <200mg/dL in order to reduce SSI rates.

Infectious complications and managements for surgical site infections in genital Paget's disease

BACKGROUND

Extramammary Paget's disease is an intra-epidermal carcinoma that occurs preferentially in genital areas. Patients with genital Paget's disease (GPD) sometimes develop severe post-surgical infections because of this anatomical disadvantage.

OBJECTIVE

To study perioperative micro-organisms and surgical site infection (SSI) in GPD.

METHODS

We examined micro-organisms isolated from preoperative lesions, necrotic sites and infected wounds in 60 adult patients with GPD who underwent surgery at our hospital between November 1990 and December 2005. Based on the obtained microbiological data, we assessed the incidence, risk factors and treatment of SSI.

RESULTS

The colonized organisms found in preoperative GPD were Enterobacteriaceae (27.6%), methicillin-sensitive Staphylococcus aureus (MSSA) (22.4%) and coagulase-negative staphylococci (CNS) (15.5%), among others. In the postoperative necrotic sites, the frequency of MSSA isolation was reduced to 9.4%, while Pseudomonas aeruginosa and methicillin-resistant S. aureus (MRSA) both increased in frequency from 3.4% and 0% upon preoperative examination to 18.8% and 9.4%, respectively. The incidence of SSI was 15%. In 7 of 9 SSIs, MRSA and/or P. aeruginosa were isolated.

CONCLUSION

We have successfully identified a number of perioperative micro-organisms in GPD. The present observations may be extremely useful in choosing appropriate antimicrobial agents for use in the surgical treatment of GPD.

Dermatite micobacteriana atípica em gato: relato de caso

Relata-se, pela primeira vez no Brasil, um caso de dermatite decorrente de infecção por micobactéria atípica do complexo Mycobacterium fortuitum-peregrinum, em espécie felina, sem raça definida, fêmea, com cinco anos de idade. Há oito meses, evoluía com lesões maculares equimóticas, nodulares, erosadas, ulceradas, acompanhadas de fístulas exsudativas, com intenso prurido e algia. Evidenciou-se a presença de micobactéria do complexo Mycobacterium fortuitum-peregrinum (grupo IV de Runyon ) identificada após evidenciação histopatológica, cultivo bacteriano e por testes bioquímicos. Após dois meses de terapia sistêmica com enrofloxacina (5mg/kg/Bid/VO) e tópica (triclosan e rifamicina) houve involução das lesões, com efeitos colaterais discretos.

Absence of tyrosine kinase mutations in Japanese colorectal cancer patients

Tyrosine kinases, which are important regulators of intracellular signal-transduction pathways, have mutated forms that are often associated with oncogenesis and are attractive targets for therapeutic intervention. Recently, systematic mutational analyses of tyrosine kinases revealed that a minimum of 30% of colorectal cancer contain at least one mutation in the tyrosine kinases. To further explore these mutations, we examined all reported mutations of NTRK3, FES, KDR, EPHA3, NTRK2, JAK1, PDGFRA, EPHA7, EPHA8, ERBB4, FGFR1, MLK4 and GUCY2F genes in the 24 colorectal cancer cell lines. Unexpectedly, among 24 colorectal cancer cell lines, only two cell lines (LoVo and CaR1) harbored mutation C1408T (R470C) in MLK4 gene. The mutation rate was extremely low compared to that previously reported. Therefore, we analyzed mutations in 46 colorectal cancer samples resected from the same number of Japanese patients. Surprisingly, none of the 46 samples contained any of the mutations reported. Based on our study, we advise that a more comprehensive tyrosine kinase gene mutation assay is necessary in the future.

Eficácia das lactonas macrocíclicas sistêmicas (ivermectina e moxidectina) na terapia da demodicidose canina generalizada

Avaliou-se a eficácia de lactonas macrocíclicas (ivermectina e moxidectina) sobre a eventual ocorrência de efeitos colaterais e acompanharam-se, após a alta parasitológica, por 12 meses, os cães tratados, visando detectar a recidiva do quadro dermatopático. Dos 63 animais, 59% eram fêmeas, 76% apresentavam precisa definição racial e 67% tinham pelame curto. A ivermectina (0,6mg/kg/dia) foi administrada por via oral a 31 cães, e a moxidectina (0,5mg/kg/cada 72 horas), pela mesma via, a 32 animais. Os tempos médios para a obtenção da primeira negativação do exame parasitológico do raspado cutâneo e para a consecução da alta foram, respectivamente, de 90 e 130 dias para a ivermectina e de 108 e 147 dias para a moxidectina. A ivermectina acarretou menos (16,1%) efeitos colaterais em relação à moxidectina (37,5%) (P=0,03). As recidivas foram, respectivamente, 10,3% e 13% para ivermectina e moxidectina. Não houve diferença entre os dois protocolos de terapia quanto aos percentuais de recidiva (P=0,67) e eficácia (P=0,61). Ambas as lactonas macrocíclicas mostraram-se eficazes: ivermectina 89,7% e moxidectina 87%.

A comparative study of the metastable equilibrium solubility behavior of high-crystallinity and low-crystallinity carbonated apatites using pH and solution strontium as independent variables

Using solution strontium and pH as independent variables, the metastable equilibrium solubility (MES) behavior of two carbonated apatite (CAP) samples has been examined, a high-crystallinity CAP (properties expected to be similar to dental enamel) and a low-crystallinity CAP (properties expected to be similar to bone mineral). CAP samples were prepared by precipitation/digestion: (CAP A: high-crystallinity, 1.3 wt% CO3, synthesized at 85 degrees C; CAP B: low-crystallinity, 6.4 wt% CO3, synthesized at 50 degrees C). Baseline MES distributions were determined in a series of 0.1 M acetate buffers containing only calcium and phosphate (no strontium) over a broad range of solution conditions. To assess the influence of strontium, MES profiles were determined in a similar fashion with 20, 40, 60, and 80% of the solution calcium being replaced on an equal molar basis by solution strontium. To determine the correct function governing CAP dissolution, ion activity products (IAPs) were calculated from the compositions of buffer solutions based on the hydroxyapatite template (Ca(10-n)Sr(n)(PO4)6(OH)2 (n = 0-10)) and the calcium/hydroxide deficient hydroxyapatite template (Ca(9-n)Sr(n)(HPO4)(PO4)5OH (n = 0-9)).

FINDINGS

(a) for CAP A, at high solution strontium/calcium ratios, the MES profiles were essentially superimposable when the solution IAPs were calculated using the stoichiometry of Ca6Sr4(PO4)6(OH)2 and for CAP B by a stoichiometry of Ca7Sr2(HPO4)(PO4)5OH; (b) for CAP A, at low strontium/calcium ratios, the stoichiometry yielding MES data superpositioning was found to be that of hydroxyapatite and for CAP B, that of calcium/hydroxide deficient hydroxyapatite. When other stoichiometries were assumed, good superpositioning of the data was not possible.