A review of decellularized stem cell matrix: a novel cell expansion system for cartilage tissue engineering

Cell-based therapy is a promising biological approach for the treatment of cartilage defects. Due to the small size of autologous cartilage samples available for cell transplantation in patients, cells need to be expanded to yield a sufficient cell number for cartilage repair. However, chondrocytes and adult stem cells tend to become replicatively senescent once they are expanded on conventional plastic flasks. Many studies demonstrate that the loss of cell properties is concomitant with the decreased cell proliferation capacity. This is a significant challenge for cartilage tissue engineering and regeneration. Despite much progress having been made in cell expansion, there are still concerns over expanded cell size and quality for cell transplantation applications. Recently, in vivo investigations in stem cell niches have suggested the importance of developing an in vitro stem cell microenvironment for cell expansion and tissue-specific differentiation. Our and other investigators' work indicates that a decellularized stem cell matrix (DSCM) may provide such an expansion system to yield large-quantity and high-quality cells for cartilage tissue engineering and regeneration. This review briefly introduces key parameters in an in vivo stem cell niche and focuses on our recent work on DSCM for its rejuvenating or reprograming effect on various adult stem cells and chondrocytes. Since research in DSCM is still in its infancy, we are only able to discuss some potential mechanisms of DSCM on cell proliferation and chondrogenic potential. Further investigations of the underlying mechanism and in vivo regeneration capacity will allow this approach to be used in clinics.

Effects of the free fatty acid content in yellow grease on performance, carcass characteristics, and serum lipids in broilers

This study was conducted to investigate whether the free fatty acid (FFA) content of yellow grease would influence the performance and carcass characteristics of broiler chicks. A total of 432 one-day-old, male Arbor Acres broilers were randomly allotted to 1 of 4 treatments, with each treatment being applied to 6 pens of 18 chicks. The dietary treatments were based on corn and soybean meal and were supplemented with either soybean oil (2.86% FFA) or yellow grease with a low (2.74%), medium (12.59%), or high (19.05%) FFA content. The fat sources were supplemented at 1.5% of the diet during the starter phase (0 to 21 d) and at 3.0% of the diet during the grower phase (22 to 42 d). From d 0 to 42, the BW gains of chicks fed diets containing soybean oil and yellow grease with 2.74% FFA were similar. As the FFA level in the yellow grease increased, the BW gain of chicks decreased (P < 0.01). The reduction in BW gain appeared to be mediated by a reduction in feed intake. The dressing percentage and the percentage of breast muscle in the carcass were significantly (P < 0.01) lower for broilers fed any yellow grease diet compared with birds fed soybean oil. In contrast, abdominal fat was significantly increased in diets containing yellow grease. These results demonstrate that the performance of birds fed yellow grease with a low content of FFA was essentially equal to that of birds fed soybean oil. However, because yellow grease samples containing FFA levels greater than 2.74% negatively affected bird performance, producers should exercise caution with regard to feeding broilers yellow grease with an elevated FFA content. In 42-d-old broilers, serum total cholesterol and low-density lipoprotein cholesterol levels were elevated in birds fed yellow grease, regardless of the dietary level. In contrast, serum high-density lipoprotein cholesterol and triglyceride levels were unaffected by dietary treatment. Although dietary FFA may influence triglyceride-rich lipoprotein metabolism in broilers, an explanation for the observed effects remains elusive.

Cadmium tolerance and accumulation in cultivars of a high-biomass tropical tree (Averrhoa carambola) and its potential for phytoextraction

Averrhoa carambola is a high-biomass tropical tree that has been identified as a Cd accumulator. In the present study, field survey, pot, and hydroponic experiments were conducted to investigate the variation of Cd tolerance and accumulation in cultivars of A. carambola as well as its potential for phytoextraction. In the field survey, it was found that concentrations of Cd in aerial tissues of A. carambola varied greatly among sites and cultivars. The Cd bioconcentration factors (BCFs) and Cd removals by the field-grown A. carambola differed significantly among sites but not among cultivars. Nonetheless, all four carambola cultivars investigated were able to accumulate considerably high concentrations of Cd in their shoots, which indicated that the 4-yr-old carambola stands could remove 0.3 to 51.8% of the total Cd content in the top 20-cm soil layer. When cultured in Cd-spiked soils, the carambola cultivar Hua-Di always showed higher Cd tolerance than the other cultivars; however, this tendency was not confirmed by hydroponic experiment. The Cd BCFs of cultivar Thailand grown in soils with 6 and 12 mg Cd kg(-1) were highest among cultivars, whereas this trend was reversed at 120 mg Cd kg(-1) treatment. Nevertheless, the pot- and hydroponics-grown carambola cultivars generally showed higher capacities to tolerate and accumulate Cd, compared with the control species. The present results indicate that a strong ability to tolerate and accumulate Cd seems to be a trait at the species level in A. carambola, although some degree of variances in both Cd tolerance and accumulation exists among cultivars.

Phytoextraction of Cd-contaminated soil by carambola (Averrhoa carambola) in field trials

Use of metal-accumulating woody species to extract metals from heavy metal contaminated soil has received more attention. While considerable studies have focused on the phytoextraction potential of willow (Salix spp.) and poplar (Populus spp.), similar information is rare for other woody species. Carambola (Averrhoa carambola) is a high-biomass tree and has been identified as a new Cd-accumulating species. The present study aimed to evaluate the Cd phytoextraction potential of carambola under field condition. After growing in a slightly Cd-contaminated site for about 170 d, the carambola stand initiated by seed-seedling with high planting density (encoded with "HD-1yr") attained a high shoot biomass yield of 18.6 t ha(-1) and extracted 213 g Cdha(-1), resulting in a 1.6-fold higher Cd removal efficiency than that of a contrasting stand established by grafted-seedling with low planting density (5.3% vs. 2%). That is, "HD-1yr" would remove 50% of the total soil Cd with 13yr, assuming that the Cd removal efficiency would not change over time. Further, one crop of "HD-1yr" significantly decreased (63-69%) the Cd uptake by subsequent vegetables. Among the four carambola stands established using grafted-seedling, the 2-yr-old stand exhibited the highest annual Cd removal efficiency (3.7%), which was yet lower than that of "HD-1yr". These results suggested that phytoextraction of Cd by carambola (especially for "HD-1yr" stand) presented a feasible option to clean up agricultural soils slightly contaminated by Cd.

An optimised, small-scale preparation of high-quality RNA from dry seeds of Davidia involucrata

INTRODUCTION

The dormancy of Davidia involucrata seeds normally lasts for an extended period of time and because of this unique property the species is an excellent model for studying the molecular mechanisms of plant dormancy. The use of minimal plant material is desirable for RNA extraction since D. involucrata is a rare plant and it is relatively difficult to collect large amounts of seeds in order to perform molecular biology studies.

OBJECTIVE

To improve the quality of RNA obtained from seeds of D. involucrata by eliminating the oxidation of polyphenols during extraction and by preventing polysaccharides and other impurities from being extracted.

METHODS

A previously described method was modified by the addition of 4% (w/v) poly(N-vinyl-2-pyrrolidone) to the dry seeds during grinding and by adding 5% (v/v) beta-mercaptoethanol and 28% (v/v) ethanol to the extraction buffer. Two further centrifugation steps (5000 and 8000 rpm) were utilised and one-seventh volume of ethanol was incubated with the supernatant at 4 degrees C for 2-3 h prior to the precipitation of RNA.

RESULTS

Following these modifications, an effective method was established for total RNA extraction from a small amount of dry seeds of D. involucrata. The isolated RNA was shown to have high purity and integrity by gel electrophoresis and spectrophotometry, and was confirmed to be suitable for RT-PCR and the construction of cDNA libraries.

CONCLUSION

The modified method reduced the amount of seeds required for extraction of total DNA and was beneficial for preserving the endangered species.

"Curettage and aspiration dissection technique" using PMOD for liver resection

BACKGROUND AND AIMS

To introduce a special dissection technique named "Curettage and Aspiration Dissection Technique" (CADT) using a versatile instrument called Peng's Multifunction Operative Dissector (PMOD) for liver resection. PMOD is an electrosurgical pencil with an inline suction, bearing four functions: electric cutting, coagulation, aspiration and dissection, The above-mentioned functions can be achieved simultaneously or sequentially during liver resection. The purpose of this study was to evaluate this technique and the special electrosurgical device in hepatic surgery.

PATIENTS AND METHODS

From June 2005 to December 2006, 70 consecutive patients with segmentectomy or major hepatectomy were performed with this dissection technique by the same surgeon. Peri-operative data and the technical aspect of this device and dissection technique for various types of liver resection were summarised.

RESULTS

Forty-nine of 70 cases with various degrees of cirrhosis. Median blood loss were 470 ml (100-2400 ml), the bleeding and mortality within one month postoperatively was zero. There were postoperative complications in 20 patients: bile leak occurred in five cases, nine cases with right pleural effusion and six with ascites. No relative complications with this method were found.

CONCLUSION

The CADT and PMOD can achieve better dissection and hemostasis. It possible is a much more valuable alternative to other devices currently used for liver surgery.

Zinc, nickel and cadmium in carambolas marketed in Guangzhou and Hong Kong, China: implication for human health

Carambola (Averrhoa carambola L.) is a popular juicy fruit throughout the tropical and subtropical world. This study was designed to quantify the levels of zinc (Zn), nickel (Ni) and cadmium (Cd) in carambolas marketed in southern China, and further to evaluate the potential health risk of human consumption of carambola. Zinc concentrations, ranging from 1.471 to 2.875 mg/kg (on fresh weight basis), were below the maximum permissible concentration for Zn in fruit of China (5 mg/kg). However, Ni concentrations (0.134-0.676 mg/kg) were considerably higher than the related recommendation values. Furthermore, Cd concentrations in 51% of the carambolas purchased from Guangzhou exceeded the maximum permissible concentration for Cd in fruit of China (0.03 mg/kg). Our results implicated that the consumption of 0.385 kg carambola contaminated by Cd per day would cause the tolerable daily intake (TDI) of Cd by the consumer to be exceeded. In addition, the remarkably high Ni concentrations in carambolas should also be of concern. The status of heavy metal contamination of carambola products marketed in the other regions and their implications for human health should be identified urgently by in-depth studies.

An optimized mini-preparation method to obtain high-quality genomic DNA from mature leaves of sunflower

In order to investigate the mutation characteristics and to further examine the genetic variation of mutant sunflower (Helianthus annuus) obtained in plants grown from seeds exposed to space conditions, only the mature tissues such as leaf and flower could be used for DNA extraction after mutation characteristics were confirmed. The rich contents of polysaccharides, tannins, secondary metabolites, and polyphenolics made it difficult to isolate high-quality DNA from mature leaves of sunflower according to previous reports. Based on the comparison of the differences in previously reported protocols, a modified method for the extraction of high-quality DNA was developed. Using this protocol, the DNA isolated from sunflower was high in quality and suitable for restriction digestion (EcoRI, HindII, BamHI), random amplified polymorphic DNA study and further molecular research. Therefore, the modified protocol was suitable for investigating the genetic variation of sunflower using mature leaf DNA.

Cadmium contamination in orchard soils and fruit trees and its potential health risk in Guangzhou, China

This study examines cadmium (Cd) contamination in orchard soils and fruit trees in Guangzhou, China, and assesses its potential health risk. Soils and tissues samples of three species of fruit trees were collected from three orchards. The average soil Cd concentration was 1.27, 1.84 and 0.68 mg/kg in orchards I, II, and III, respectively. The carambola (Averrhoa carambola) accumulated exceptionally high concentrations of Cd (7.57, 10.84, 9.01 and 2.15 mg/kg dw in root, twig, leaf and fruit, respectively), being 6.0-24 times and 4.0-10 times the corresponding tissue Cd in the longan (Dimocarpus longan) and wampee (Clausena lansium), respectively. Furthermore, all Cd concentrations (0.04-0.25 mg Cd/kg fw) of the fruits exceeded the tolerance limit of cadmium in foods of PR China (0.03 mg/kg fw). Our results indicate that the carambola tree has high Cd accumulation capacity and might be a Cd accumulator; and its fruit, among the three species of fruits studied, also poses the highest potential health risk to local residents.

Nonlinear optical frequency conversion with stopped short light pulses

Efficient nonlinear optical frequency conversion is proposed and theoretically demonstrated by use of stopped short light pulses in a doubly resonant Bragg reflector. The pump pulse is shown to decelerate and stop in the reflector, and the stopped pump field reinforces the interaction with stimulated Raman scattering. The temporal walk-off between the pump pulse and the generated Raman pulse can be substantially reduced with the doubly resonant Bragg structure. Numerical simulations show that the conversion from the picosecond pump pulse to Stokes wave can reach 85%.

Binding pancreaticojejunostomy--a safe and reliable anastomosis procedure

BACKGROUND

Over the past one hundred years, the development of pancreaticoduodenectomy (PD) has always involved the struggle against pancreatic leakage. Until now, leakage of the pancreatic anastomosis has remained a common and serious complication after PD. Various methods of dealing with the pancreatic stump for prevention of pancreatic anastomotic leakage have been described. No matter which method is used, however, pancreatic anastomotic leakage is still most likely to occur when anastomosis involves a normal and soft pancreas.

METHODS

To perform a safe and reliable pancreaticoenteric anastomosis, we investigated the risk factors and potential mechanisms of occurrence of pancreatic leakage, including leakage from the needle hole and from the seam between two anastomosed structures, blood supply to the anastomosis and tension at the anastomosis. Based on these findings, we established a new pancreaticoenteric anastomosis procedure - binding pancreaticojejunostomy. The unique aspects of this procedure are as follows. The sero-muscular sheath of jejunum is bound to the invaginated pancreatic stump, so as to seal the gap between them; mucosa of the segment of jejunum that would eventually be in contact with the pancreatic stump is destroyed either chemically or by electric coagulation to promote healing. There is no needle hole on the jejunal surface of the anastomotic site.

RESULTS

From 1996 to 2003, a total of 227 consecutive patients were treated with this type of pancreaticojejunostomy in this institution. None of the patients developed a pancreatic anastomotic leak.

DISCUSSION

Binding pancreaticojejunostomy is a safe and reliable anastomotic procedure to effectively minimize leakage even when the texture of the pancreas is soft and normal.

[The objective detection and description of the types of pulse based on the Chinese traditional medical science]

Through the study of the classical works of "The Pulse Studies of Binhu", the possibility and methods of the realization of the objective detection and description of all types of pulse based on the Chinese Traditional Medical Science(CTMS) have been proved, and a design scheme of a complete atlas of the types of pulse based on the CTMS is presented in this paper.

Detection of amp C in Enterobacter cloacae in China

PCR amplification of 55 strains of Enterobacter cloacae indicated 51 of them had amp C structural gene verified by DNA sequence and Southern blotting. All PCR products were cleaved into 666- and 328-bp fragments by Kpn1 restriction enzyme. Imipenem was the most potent inducer for mRNA expression of amp C gene and beta-lactamase activity. The beta-Lactamase inhibitor R0481220 strongly inhibited Amp C beta-lactamases; 96.4% (53/55) of Enterobacter cloacae producing Amp C enzyme were susceptible to cefepime.

Synthesis of ethyl alkylidene alpha cyanoacetates under ultrasound irradiation

Condensation of ketones with ethyl cyanoacetate catalysed by ammonium acetate-acetic acid results in ethyl alkylidene alpha cyanoacetate in 31-89% yield under ultrasound irradiation.

The in vitro activity of sulbactam combined with third generation cephalosporins against third generation cephalosporin-resistant bacteria

The in vitro activity of the beta-lactamase inhibitor sulbactam combined with cefuroxime, cefotaxime or ceftazidime in the ratio of 1:1 was studied against ceftazidime- or cefuroxime-resistant Gram-negative rods and Staphylococcus aureus. Sulbactam enhanced the antibacterial activities of cefuroxime, cefotaxime and ceftazidime against Gram-negative rods. The MIC(90) of ceftazidime against Escherichia coli, Enterobacter cloacae, Citrobacter freundii, Acinetobacter spp. and Pseudomonas aeruginosa was reduced 4-fold and that of cefotaxime against E. coli, E. cloacae, C. freundii and Acinetobacter spp. reduced by 2-4-fold. However, sulbactam did not enhance the activities of cefuroxime, cefotaxime or ceftazidime against S. aureus, enterococci and Stenotrophomonas maltophilia. With the combination of sulbactam and ceftazidime at the ratio of 1:1, 38.4% of E. coli, 45.3% of E. cloacae, 66.6% of C. freundii and 60% of Acinetobacter spp. initially resistant to ceftazidime became susceptible.

Genome-wide allelotype analysis of sporadic primary nasopharyngeal carcinoma from southern China

Nasopharyngeal carcinoma (NPC) is one of the most common malignant tumors in Southern China, especially in the Guangdong area. To demonstrate a comprehensive profile of loss of heterozygosity (LOH) in NPC, we applied a large panel of 382 microsatellite polymorphism markers covering all the 22 autosomes in 98 cases of sporadic primary NPC. Of the 335 informative markers, 83 loci showed high level of LOH (presence in equal to or more than 30% cases) and most of the high frequent loci were clustered to chromosome 1p36 and 1p34, 3p14-p21, 3p24-p26, 3q25-q26 and 3q27, 4q31 and 4q35, 5q15-21 and 5q32-q33, 8p22-p23, 9p21-p23 and 9q33-q34, 11p12-p14, 13q14-q13 and 13q31-q32, 14q13-q11, 14q24-q23 and 14q32. High frequency of LOH was found in chromosomes 3, 5, 9 and 11 (>/=50%), while medium frequency of LOH was found in chromosomes 1, 4, 6, 14, 17 and 19 (40-49%). Several new regions showing high frequency of LOH were found in chromosome 1p36, 3q25-q26, 3q27, 5q15-q21, 8p22-p23 and 11p12-14. The relationship between LOH and TNM stage of NPC was evaluated. Regions 6p23 (D6S289), 8p23.1 (D8S549) and 9q34.2 (D9S1826) showed higher frequency of LOH in later stages (III and IV) than in earlier stages (I and II) (P<0.05). Thus, our study provides a global view on allelic loss in the development of NPC and should shed light on the way for localization of putative tumor suppressor genes associated with the pathogenesis of NPC.

Accuracy of patient prediction of allergy skin test results

BACKGROUND

The ability of patients to self-diagnose allergy is unknown.

OBJECTIVE

To estimate the ability of patients to correctly predict the results of allergy skin tests.

METHODS

We conducted a structured interview of 86 patients with chronic rhinitis or asthma undergoing aeroallergen skin tests. We asked, "Do you expect the skin tests to be positive or negative?" and "What do you expect the allergy tests to be positive for?" Responses to these questions were correlated with the results of aeroallergen skin tests. Skin tests were performed using the prick technique and included cat, grass pollen, tree pollen, weed pollen, dust mites, and molds.

RESULTS

Seventy-three participants provided usable responses. Of those with a positive skin test, the number (percentage) of participants who predicted correctly was 10/18 (56%) for cat, 4/14 (29%) for tree, 7/26 (27%) for weeds, 5/23 (22%) for dust mite, 2/12 (17%) for grass, and 1/8 (12%) for mold. Of those with a negative skin test, the number (percentage) of participants who predicted correctly was 47/50 (94%) for dust mite, 51/59 (86%) for trees, 56/65 (86%) for mold, 52/61 (85%) for grass, 45/55 (82%) for cat, and 38/47 (81%) for weeds.

CONCLUSIONS

(1) Patients have limited ability to correctly predict positive skin tests to aeroallergen. (2) Patients are able to predict negative skin tests with reasonable accuracy. (3) "What do you think you are allergic to?" may be a good screening question for patients with asthma and rhinitis.

Reduction of vancomycin use in orthopedic patients with a history of antibiotic allergy

OBJECTIVE

To reduce prophylactic vancomycin use in patients with a history of penicillin or cephalosporin allergy undergoing elective orthopedic surgery by using a targeted allergy consultation and penicillin allergy skin testing.

PATIENTS AND METHODS

The participants in this practice improvement study were patients with a history of penicillin or cephalosporin allergy who were scheduled for elective orthopedic surgery and referred by orthopedic surgeons for allergy consultation and penicillin allergy skin testing between September 22, 1998, and April 15, 1999. The primary outcome measure was the percentage of participants who received prophylactic cefazolin during the study period compared with historical controls.

RESULTS

Of the 60 study patients, 59 received a penicillin allergy skin test, 58 underwent orthopedic surgery, and 55 received antibiotic prophylaxis. Fifty-five patients had a history of allergy to penicillin, a cephalosporin, or both, and 5 had a history of nonspecific antibiotic allergy. Of the 59 patients, 55 (93%) had negative penicillin allergy skin test results. Fifty-four (90%) of the 60 patients were given clearance by the allergist to receive cefazolin. Of the 55 study patients who received antibiotic prophylaxis, 6 (11%) received vancomycin compared with 38 (30%) of 127 historical controls (P < or = .05). None of the study patients had an immediate reaction to cefazolin or to vancomycin.

CONCLUSION

Prophylactic vancomycin use in patients with a history of penicillin or cephalosporin allergy undergoing elective orthopedic surgery can be reduced by a targeted allergy consultation and penicillin allergy skin testing.

A dose-ranging study of fluticasone propionate administered once daily via multidose powder inhaler to patients with moderate asthma

STUDY OBJECTIVE

This dose-ranging study evaluated the clinical efficacy and safety of inhaled fluticasone propionate administered once daily via a multidose powder inhaler in patients with moderate asthma (FEV(1), 45 to 75% predicted).

MATERIALS AND METHODS

In this multicenter trial, 330 patients (> or = 12 years old) previously receiving inhaled corticosteroids or beta(2)-agonists alone were randomized in a double-blind manner to receive fluticasone propionate at 100, 200, or 500 microg once daily or matching placebo for 12 weeks.

RESULTS

Once-daily treatment with fluticasone propionate resulted in an improvement in efficacy variables, such as FEV(1), morning and evening peak expiratory flow (PEF), asthma symptom scores, nighttime awakenings, albuterol use, and duration of study participation. A dose-related trend was observed for improvements in morning and evening PEF and albuterol use. Statistical significance for pairwise comparisons was achieved for 200 microg and 500 microg fluticasone propionate vs placebo for all efficacy variables, and for 100 microg fluticasone propionate vs placebo for morning and evening PEF at most or all time points. Drug-related adverse events were few (< or = 5%) and mostly related to the topical effects of inhaled corticosteroids. No dose-response effect or clinically relevant differences were observed in morning plasma cortisol concentrations or after cosyntropin stimulation.

CONCLUSION

Once-daily treatment with fluticasone propionate was well tolerated and demonstrated some dose-related trends in improvements in lung function and asthma control in patients with moderate asthma.

Consultation for asthma: results of a generalist survey

BACKGROUND

There are few studies that examine referral patterns for asthma and few studies that examine the referring physicians' reasons for consultation.

OBJECTIVE

The purpose of this study was to survey generalist physicians on their referral patterns for adult patients with asthma.

METHODS

We mailed a questionnaire to all the staff (faculty) in the Department of Family Medicine and the Division of Community Internal Medicine at the Mayo Clinic in Rochester, Minnesota. There were 37 completed questionnaires (18 family medicine and 19 internal medicine) out of a total of 58 for a response rate of 64%. The survey asked what were reasons for consultation, whether allergists or pulmonologists were preferred, and the characteristics of a good consultation.

RESULTS

We asked respondents to indicate "how often you consult a specialist for an adult asthma patient" for a variety of clinical indications. The percentage responding "always" (for the top five indications) were if the patient requests one (46%), for allergen immunotherapy (38%), for single life-threatening attack (27%), for allergy testing (14%), and for steroid-dependent asthma or poorly controlled asthma (11%). Twenty-seven percent of respondents generally consulted allergists only, 22% generally consulted pulmonologists only, 3% indicated both, while 46% had no preference. Respondents did express a preference for a pulmonologist when the reported reason for the consultation was diagnosis of asthma uncertain, chronic cough, asthma in smoker, exercise training, or for an allergist when the reported reason for consultation was allergy evaluation or immunotherapy. The respondents indicated that the top six characteristics of a good consultation were the following: clear recommendations, clinically appropriate recommendations, high patient satisfaction, including recommendations for future management scenarios, including educational content in the consultation, and calling the referring physician before requesting a secondary consultation.

CONCLUSIONS

These results suggest that while consultation occurs often for severe or uncontrolled asthma, some asthma patients who may benefit from consultation may not be seeing the specialist. There were no systematic preferences for consultations with allergists versus pulmonologists for asthma although for some clinical indications pulmonologists or allergists were favored. Referring physicians value clear, clinically appropriate recommendations.

Systemic reactions to allergy skin tests

BACKGROUND

Skin testing is a common diagnostic tool in allergy. It is considered a safe procedure, although systemic reactions have been reported.

OBJECTIVE

To identify the systemic reaction rates of allergy skin tests and to determine the clinical outcome of such reactions.

METHOD

This retrospective study used a computerized database at the Mayo Clinic to identify patients who developed systemic reactions to skin tests. Altogether 497,656 skin tests were performed on 18,311 patients from January 1992 to June 1997. Skin puncture tests were performed on 16,505 patients. Skin puncture and intradermal skin tests were performed on 1,806 patients. Systemic reactions were evaluated and treated by physicians.

RESULTS

There were 6 systemic reactions, an overall rate of 33 systemic reactions per 100,000 skin tests. All six patients had asthma. The systemic reaction rates for latex skin testing was 152 or 228 reactions per 100,000 latex skin tests, to penicillin and antibiotics 72 reactions per 100,000 penicillin and antibiotics skin tests, and to aeroallergens 15 or 23 reactions per 100,000 aeroallergen skin tests. The systemic reaction rate for skin puncture test was 30 reactions per 100,000 skin puncture tests, for skin puncture and intradermal skin tests, the rate was 55 reactions per 100,000 skin puncture and intradermal skin tests. All 6 patients were treated and dismissed within 1 hour after treatment.

CONCLUSION

The systemic reaction rate to skin tests was very low. Systemic reactions were mild and all patients recovered fully within 1 hour.

Fluticasone propionate powder and lack of clinically significant effects on hypothalamic-pituitary-adrenal axis and bone mineral density over 2 years in adults with mild asthma

BACKGROUND

Although inhaled corticosteroids are widely used for the treatment of inflammation in asthma, prospective, long-term, placebo-controlled trials characterizing their systemic safety with chronic use are lacking.

OBJECTIVE

This study was designed to prospectively evaluate the long-term safety of inhaled fluticasone propionate therapy.

METHODS

Fluticasone propionate powder, 500 microgram, or placebo was administered twice daily by means of the Diskhaler for 104 weeks to 64 adults with mild persistent asthma in a randomized, double-blind, parallel-group study. Primary safety variables were measured at baseline and every 6 months thereafter. Although evaluation of efficacy was not an objective of this study, pulmonary function testing was performed at monthly intervals.

RESULTS

Two years of treatment with fluticasone propionate had no significant effects on the skeletal system. No clinically significant changes were observed in ophthalmic parameters (glaucoma and posterior subcapsular cataracts). Mean change from baseline in lumbar spine (L1 to L4 ) bone density at week 104 was not significantly different between fluticasone propionate (-0.006 +/- 0.008 g/cm2) and placebo (-0.007 +/- 0.010 g/cm2). Markers of bone formation (serum osteocalcin) and resorption (urinary N-telopeptide) did not differ significantly between treatment groups. The effects of fluticasone propionate treatment on the hypothalamic-pituitary-adrenal axis were minimal, with no alterations in morning plasma cortisol concentrations and minor but statistically significant decreases in poststimulation mean peak plasma cortisol concentrations (P =.021) and 8-hour plasma cortisol area under the curve values (P =.020) at week 104. Drug-related adverse events were primarily topical effects of inhaled corticosteroids. Pulmonary function improved significantly during 2 years of fluticasone propionate treatment.

CONCLUSION

Fluticasone propionate powder, 500 microgram twice daily for up to 2 years, was efficacious and well tolerated, with no clinically relevant effects on the hypothalamic-pituitary-adrenal axis, bone density, or ophthalmic parameters in adults with mild asthma.

Effects of fluticasone propionate, triamcinolone acetonide, prednisone, and placebo on the hypothalamic-pituitary-adrenal axis

BACKGROUND

Many clinicians are reluctant to prescribe inhaled corticosteroids because of concerns over potential effects on the hypothalamic-pituitary-adrenal axis.

OBJECTIVE

The purpose of this study was to compare the adrenal responses to 6-hour cosyntropin infusion after treatment with fluticasone propionate aerosol, triamcinolone acetonide aerosol, prednisone, and placebo for 4 weeks, a sufficient time interval to assess any effects on the adrenal response to stress.

METHODS

This double-blind, triple-dummy, randomized, placebo-controlled study was conducted in 128 patients to evaluate adrenal response to 6-hour cosyntropin infusion (a clinically relevant method for evaluating adrenal function) after 28 days of treatment with fluticasone propionate aerosol 88 microg or 220 microg twice daily, triamcinolone acetonide aerosol 200 microg 4 times daily or 400 microg twice daily, prednisone 10 mg once daily, and placebo.

RESULTS

After 28 days of treatment, mean plasma cortisol response to cosyntropin over 12 hours after initiation of the 6-hour infusion was similar among fluticasone, triamcinolone, and placebo groups; cortisol response was significantly (P <.05) reduced after treatment with prednisone compared with the other treatment groups. Mean 8-hour area under the plasma cortisol concentration-time curves and peak plasma cortisol concentrations were significantly (P </=.003) lower with prednisone than any other treatment; no significant differences were noted between placebo and either of the fluticasone groups in any assessment. Mean reductions from baseline in area under the plasma cortisol concentration time curves and peak cortisol concentrations were significantly (P <.05) greater with triamcinolone 400 microg twice daily compared with placebo.

CONCLUSION

These results suggest that fluticasone propionate at therapeutic doses has effects on the hypothalamic-pituitary-adrenal axis comparable to that of placebo and has significantly less effect than prednisone as measured by 6-hour cosyntropin infusion after 28 days of treatment.

Diagnosis and management of rhinitis: complete guidelines of the Joint Task Force on Practice Parameters in Allergy, Asthma and Immunology. American Academy of Allergy, Asthma, and Immunology

This document contains complete guidelines for diagnosis and management of rhinitis developed by the Joint Task Force on Practice Parameters in Allergy, Asthma and Immunology, representing the American Academy of Allergy, Asthma and Immunology, the American College of Allergy, Asthma and Immunology and the Joint Council on Allergy, Asthma and Immunology. The guidelines are comprehensive and begin with statements on clinical characteristics and diagnosis of different forms of rhinitis (allergic, non-allergic, occupational rhinitis, hormonal rhinitis [pregnancy and hypothyroidism], drug-induced rhinitis, rhinitis from food ingestion), and other conditions that may be confused with rhinitis. Recommendations on patient evaluation discuss appropriate use of history, physical examination, and diagnostic testing, as well as unproven or inappropriate techniques that should not be used. Parameters on management include use of environmental control measures, pharmacologic therapy including recently introduced therapies and allergen immunotherapy. Because of the risks to patients and society from sedation and performance impairment caused by first generation antihistamines, second generation antihistamines that reduce or eliminate these side effects should usually be considered before first generation antihistamines for the treatment of allergic rhinitis. The document emphasizes the importance of rhinitis management for comorbid conditions (asthma, sinusitis, otitis media). Guidelines are also presented on special considerations in patients subsets (children, the elderly, pregnancy, athletes and patients with rhinitis medicamentosa); and when consultation with an allergist-immunologist should be considered.

Algorithm for the diagnosis and management of asthma: a practice parameter update: Joint Task Force on Practice Parameters, representing the American Academy of Allergy, Asthma and Immunology, the American College of Allergy, Asthma and Immunology, and the Joint Council of Allergy, Asthma and Immunology

This algorithm on the diagnosis and treatment of asthma is intended to complement and update the previously published Practice Parameters for the Diagnosis and Treatment of Asthma. Both documents were developed by the Joint Task Force on Practice Parameters, representing the AAAAI, ACAAI, and the JCAAI. The authors of this asthma algorithm have attempted to include all the elements essential for the diagnosis and care of patients with asthma. Every effort was made to keep the algorithm clear and concise, yet thorough and complete (Fig 1). Each component of the algorithm is elaborated further in a brief annotation. For further discussion, the reader is referred to the more extensive Practice Parameters for the Diagnosis and Treatment of Asthma.

Joint Task Force Algorithm and Annotations for Diagnosis and Management of Rhinitis

The algorithm and text annotations in this document are intended to assist clinical decision making about patients who present with symptoms of rhinitis. This document complements the Executive Summary of Joint Task Force Practice Parameters for Diagnosis and Management of Rhinitis (Ann Allergy, Asthma, Immunol 1998; 81:463-468) and Diagnosis and Management of Rhinitis: Complete Guidelines of the Joint Task Force on Practice Parameters in Allergy, Asthma and Immunology (Ann Allergy, Asthma, Immunol 1998;81:478-578). The Joint Task Force on Practice Parameters in Allergy, Asthma and Immunology is co-sponsored by the American Academy of Allergy, Asthma and Immunology, the American College of Allergy, Asthma and Immunology and the Joint Council of Allergy, Asthma and Immunology.

The physician as advocate

Health-care advocacy extends beyond the understanding of environmental, social, and economic factors that affect health. Patient advocacy is more than a role--it is a principle that governs the patient-physician relationship and the practice of medicine. Physicians should be reminded that the healing power of medicine is not self-appointed. The authority of medicine derives from the principle of patient advocacy--that is, for 3,500 years society has identified, separated, and commissioned physicians for the sole purpose of providing care to sick and suffering patients. If we physicians compromise on patient advocacy, we will surely surrender this commission.

Reduction of dimesna to mesna by the isolated perfused rat liver

Mesna is administered with ifosfamide and cyclophosphamide to reduce the incidence of hemorrhagic cystitis. In the present model of mesna metabolism and disposition, mesna is rapidly and irreversibly oxidized to dimesna in the plasma, passes unchanged through the liver, and is then reduced by the kidney and excreted. Our detection of a high ratio of mesna to dimesna in the plasma of clinical samples led us to reinvestigate the hepatic metabolism of mesna and dimesna. We perfused isolated rat livers from female Sprague Dawley rats with protein-free buffered solution containing dimesna at concentrations observed during therapy. In single-pass perfusions, each liver was perfused with up to three dimesna concentrations during consecutive 20-min periods. Recirculating perfusions were used to study single supratherapeutic concentrations of dimesna or mesna. Mesna and dimesna concentrations were measured by specific chromatographic procedures. Dimesna reduction, adjusted by the effluent flow rate and liver weight (0.4-58.5 nmol/min/g liver), correlated closely by linear regression (r = 0.98; n = 36) to the perfused dimesna concentration (4.2-249 microM), indicating a clearance of 0.20 ml/min/g liver. The concentration of dimesna that entered the liver closely matched the summed concentration of mesna and dimesna emerging in the effluent perfusate (single-pass experiments: slope, 0.98; intercept, -0.30; r = 1.00; n = 31). Only trace amounts of unidentified thiols were detected in the bile during recirculation of perfusates with 1 mM mesna or 250 microM dimesna. The effluent mesna concentration correlated inversely with the flow rate, which was consistent with a low extraction ratio in the perfusion model. These data suggested that the dimesna reduction rate was limited by hepatic uptake. Dimesna reduction was decreased by agents that deplete glutathione. Pretreatment of rats with up to 100 mg/kg ifosfamide did not impair hepatic dimesna reduction. In control experiments, dimesna was not reduced during recirculation through the apparatus without a liver. Mesna was oxidized to dimesna during oxygenation of the perfusate in the reservoir, but mesna injected directly into the perfusate just before entry into the liver passed unchanged into the effluent. Extrapolation of the dimesna clearance data from the perfusion model to humans suggests that hepatic dimesna reduction may counterbalance the rapid oxidation of mesna in plasma. The proposed equilibrium is consistent with clinical observations and suggests a new model for mesna metabolism and disposition.

Similar bioavailability of single-dose oral and intravenous mesna in the blood and urine of healthy human subjects

Although mesna has been used for more than a decade to reduce the incidence of hemorrhagic cystitis induced by ifosfamide and cyclophosphamide, the disposition of i.v. and oral mesna has not been adequately described. To obtain accurate bioavailability data for the design of mesna regimens, we developed procedures to preserve and measure mesna and dimesna in the blood and urine and studied 25 volunteer subjects who received single doses of i.v. mesna and four different formulations of oral mesna in a five-way randomized crossover study. The dose-adjusted area under the blood concentration-time curve showed no difference in bioavailability for i.v. and oral mesna; however, the maximum mesna concentration after oral doses was 16% of that estimated for i.v. doses. The short initial half-life of i.v. mesna indicated that mesna was rapidly cleared; however, the blood concentrations of mesna uniformly exceeded those of dimesna after oral as well as i.v. doses, which suggested that reduced mesna and oxidized mesna disulfide are in equilibrium. The ratio of mesna:dimesna was higher in protein-free plasma than it was in the urine, which suggested that most urinary mesna is produced by glomerular filtration of mesna rather than by renal tubular reduction of dimesna. The sum of mesna and dimesna excretion after the i.v. doses (73% of the dose) and the four oral formulations (68-73%) showed no difference in urinary bioavailability, consistent with the blood data. However, the urinary bioavailability of the therapeutically active free-thiol mesna was greater after i.v. doses (40% of the dose) than it was after oral doses (31-33%). The ratio of oral:i.v. mesna excretion ranged from 0.52-1.23 (mean, 0.82) among the 24 subjects. Urinary mesna concentrations exceeded 50 microM in all subjects for up to 12 h after oral doses as compared to 4 h after i.v. doses. About 90% of this mesna was excreted by hour 2 after i.v. doses and by hour 9 after oral doses. The mean maximum concentration of mesna in blood and excretion into urine were both 2.6 h after dosing. The oral formulations thus showed sustained urinary excretion, and their urinary bioavailability approached that of i.v. mesna.

Ultrasound-promoted preparation of disteryl ethers catalyzed by montmorillonite K 10

In the presence of montmorillonite K 10, 5(6)-unsaturated sterols (1) were heated under ultrasound at 45 degrees C in dichloromethane for 2-5.5 h to provide 3 beta,3'beta-5(6)/5'(6')-unsaturated disteryl ethers (2) in 35-79% yield. Meanwhile, 3 alpha,3'alpha-diandrost-5-en-17-one-3-yl ether (3a) and 3 alpha,3'alpha-dipregn-5-en-20-one-3-yl ether (3b) were also obtained as by-products from 3 beta-hydroxyl-androst-5-en-17-one (1a) and 3 beta-hydroxyl-pregnan-5-en-20-one (1b) respectively.

Phase I clinical trial of cefditoren pivoxil (ME 1207): pharmacokinetics in healthy volunteers

Pharmacokinetics of ME1207 were evaluated in 5 groups of healthy adult male volunteers given single preprandial administration of 100, 200 and 300 mg; postprandial administration of 200 mg; and administration of 200 mg every 12 h for 7 consecutive days. Blood drug concentrations were determined by HPLC and bioassay after oral single administration of 100, 200 and 300 mg before meals. Serum concentrations and major pharmacokinetic parameters (Cmax, Tmax, AUC and T1/2 Ke) determined by these two methods were comparable. Cmax and AUC determined by bioassay after postprandial administration were greater than those determined after preprandial administration. Blood concentrations determined 1.5 and 12 h after each administration, during repeated administration of 200 mg every 12 hours for 7 days, were always about 2.5 and 0 mg/l, respectively, indicating that the drug is not accumulated in the body. Within 24 hours after administration of 100, 200 and 300 mg, 19.93 +/- 5.20, 20.24 +/- 3.72 and 21.29 +/- 5.47%, respectively, of the dose were excreted into urine in an unchanged form.

Pharmacokinetics of an intravenous-oral versus intravenous-mesna regimen in lung cancer patients receiving ifosfamide

PURPOSE

To compare the pharmacokinetics of the approved I.V. (intravenous) mesna regimen and an investigational I.V.-oral regimen that could be used in outpatients who receive ifosfamide.

PATIENTS AND METHODS

The I.V. regimen consisted of three I.V. mesna doses given at 0, 4, and 8 hours after ifosfamide administration. The investigational regimen included an I.V. mesna dose given concurrently with ifosfamide, followed 2 and 8 hours later by oral administration of mesna tablets. I.V. and oral mesna doses equaled 20% and 40%, respectively, of the ifosfamide dose. The study subjects were 12 lung cancer patients who received ifosfamide 1.2 g/m2 daily for 5 days. The patients were randomized to receive either the I.V.-oral or I.V. mesna regimen on day 1, followed by crossover to the other regimen on days 2 through 5 of ifosfamide treatment. The urinary profiles of mesna and dimesna excretion were determined on days 1, 2, and 5; pharmacokinetic parameters for blood samples were determined only on day 5.

RESULTS

During the first 12 hours after ifosfamide administration, the amount of mesna excreted and the profile of urinary mesna excretion was similar for both regimens; however, the I.V.-oral regimen showed less fluctuation in the excretion rate and higher trough values. During hours 12 to 24, about eightfold more mesna was excreted by patients given the I.V.-oral than the I.V. regimen.

CONCLUSION

These pharmacokinetic data show that the I.V.-oral regimen should be at least as uroprotective as the I.V. mesna regimen. Patients may also benefit from the I.V.-oral regimen because of the higher trough values during hours 0 through 12 and the sustained urinary mesna excretion during hours 12 through 24.

Aerosol beclomethasone dipropionate spray compared with theophylline as primary treatment for chronic mild-to-moderate asthma. The American Academy of Allergy, Asthma and Immunology Beclomethasone Dipropionate-Theophylline Study Group

BACKGROUND

Inhaled corticosteroids and oral theophylline are effective treatments for moderate asthma.

OBJECTIVE

We sought to compare the benefits and adverse reactions of theophylline and aerosol beclomethasone spray.

METHODS

A multicenter, double-blind, double-placebo, randomized, controlled trial of 1-year duration was performed. Seven hundred forty-seven patients with asthma received either beclomethasone dipropionate aerosol spray (84 microg four times per day) or sustained-release theophylline twice per day in doses adjusted for optimum control of the disease. The main outcome measures were daily diary of symptoms and peak flow rates (recorded on a mark-sense computer-readable form); supplemental bronchodilator use; doctor's office or hospital visits and absence from work or school; spirometry; methacholine testing; adverse experiences; and cortisol blood measurements.

RESULTS

Both treatment strategies reduced symptoms promptly and achieved low absenteeism from work or school and low rates of emergency treatment for asthma. Both maintained nearly normal pulmonary function. Beclomethasone was statistically significantly more effective in reducing symptoms, supplemental bronchodilator and systemic glucocorticoid doses, bronchial hyperresponsiveness, and eosinophilia. However, the magnitude of these differences was small. Theophylline caused more headache, nervousness, insomnia, and gastrointestinal distress, and more patients discontinued treatment because of side effects. Beclomethasone caused more oropharyngeal candidiases and hoarseness and reduced morning plasma cortisol levels before and after cosyntropin. It reduced the rate of growth in children. No new cataracts or glaucoma developed.

CONCLUSION

Theophylline effectively controlled symptoms at lower than the customarily recommended blood level. The risk/ benefit profiles of these agents suggest that inhaled corticosteroids may be the preferred agent for most adult patients and for some children.

Phase I clinical trial of cefditoren pivoxil (ME1207). Tolerance in healthy volunteers

A tolerance study to ME1207 was conducted in healthy volunteers using five single doses administered before a meal (50, 100, 200, 300 and 500 mg), a single 200 mg dose administered after a meal, and 200 mg administered every 12 h for 7 days. No subjective symptoms or changes in haematological and biochemical examinations and urinalysis were observed after single administration of 50 to 500 mg Four subjects complained of minimal upper abdominal discomfort when 200 mg was administered every 12 h for 7 days, but this symptom disappeared without remedial action in all cases. Therefore ME1207 was thought to be safe when orally administered at the above-mentioned doses by the above-mentioned administration methods.