To skim or splice? Comparing the quantification of M-proteins using two peak-integration protocols across multiple electrophoresis platforms.

OBJECTIVES: M-protein quantification by peak integration in serum protein electrophoresis (SPE) plays a central role in diagnosing, prognosing and monitoring monoclonal gammopathies. The conventional perpendicular drop (PD) integration approach integrates M-spikes from the baseline, which performs acceptably when the M-protein concentration is relatively high compared to the amount of background proteins present. The alternative peak-integration protocol by tangential skim (TS), however, allows for more accurate M-protein estimations by excluding background proteins. Despite some guideline recommendations, TS has been poorly adopted, making an understanding of the differences between the two protocols and their potential impacts paramount when considering a change from PD to TS. DESIGN & METHODS: We conducted retrospective investigations of the differences in M-protein quantification over large concentration ranges between PD and TS on 3 of the most popular electrophoresis platforms. RESULTS: Compared to PD, TS gave consistently lower results; the differences between the two methods increased tremendously and became more sporadic as M-protein concentrations dropped below 15 g/L in all 3 platforms. At < 15 g/L, the average % difference ranged from -81 % to -95 %, while above 15 g/L, the average % difference was only -13 to -31 %. Medical decision point analyses using linear regression predicted statistically significant and platform-dependent differences, which could impact clinical interpretation. CONCLUSIONS: Careful consideration of the magnitude of concentration changes and the potential impacts on patient classification and management should be made when switching to TS for M-protein quantification.

Comparing respiratory polygraphy with pulse transit time analysis versus overnight polysomnography in the diagnosis of obstructive sleep apnoea in children.

OBJECTIVE: Obstructive sleep apnea syndrome in children is associated with significant morbidity. Polysomnography is the main diagnostic tool but is time consuming and requires skilled manpower to supervise the patient overnight and hence long referral to diagnosis time. However, there are limitations and underestimation of the apnoea hyponea index (AHI) with alternative home sleep apnoea testing (HSAT), such as type 3 respiratory polygraphy (RP). Prior studies have demonstrated pulse transit time (PTT) to be a reliable indicator of cortical arousals. In this study, the use of PTT together with RP will be studied to determine whether the derived AHI is comparable to that of PSG. METHOD: Forty-five patients with suspected OSA met the inclusion criteria underwent PSG in the sleep laboratory for analysis. The raw data for either PSG or RP analysis were allocated separately to two different accredited sleep technicians. The primary outcome AHI derived from PTT with RP was compared to the AHI derived from PSG. Secondary outcomes compared were obstructive apnoea index (OAI), total hypopnoea index (THI) and arousal index (AI). Bland Altman analysis was used to compare the agreement of AHI derived from the 2 modalities and demonstrate whether RP is non inferior or equivalent to the gold standard for diagnosing OSAS. RESULTS: The patients studied had a median age of 8.8 years (range 3-17 years). The patients were not limited to certain spectrum of severity OSA and had AHI results spread from mild to severe OSA (AHI 0.4/hr to 72.2/hr). The RP with PTT-derived AHI was strongly correlated to the PSG derived AHI as seen on the Spearman plot (r = 0.98). The Bland Altman plot showed no evidence of underestimation of the AHI due to missed arousal related hypopneas. The difference of AHI derived from RP and PSG results were clinically insignificant. The differences between the PSG and RP total hypopnoea index (THI) and arousal index (AI) were also statistically insignificant. CONCLUSION: The study shows that RP with PTT can be considered a reliable diagnostic alternative compared with PSG. The role of PTT incorporated with RP was to minimize underestimation of AHI due to missed arousal associated hypopnea events. The results were apparent across mild to severe severity of OSA. There are advantages of RPs particularly in paediatrics. Overall this study offers promising preliminary insights that RP incorporated with PTT can be further explored as an acceptable home diagnostic tool for diagnosing OSA in children.

Hybrid procedure for orbital venous malformation in the endovascular operation room.

PURPOSE: To describe a hybrid procedure for orbital venous malformation in the endovascular operating room (EVOR). METHODS: Five consecutive patients with venous malformation in the periocular and orbital region were included. All patients received a one-stage direct puncture venogram, image-guided glue injection, and surgical resection in the EVOR equipped with a biplane digital subtraction angiography system (BDSAS). RESULTS: The mean age at the time of operation was 37.4 years (range, 22-69 years). The mean operative time was 193 min (range, 138-324 min). No intraoperative complications were noted. The mean follow-up duration was 18.8 months (range, 10-24 months). Three patients had complete removal of the vascular lesions. At the latest follow-up, no recurrence of symptoms related to the lesions was noted. All patients had an uneventful recovery and satisfactory outcome. CONCLUSIONS: The hybrid procedure of orbital venous malformation in the EVOR is a novel application in ophthalmology. It is a safe and well-controlled procedure with real-time high-quality BDSAS surveillance to facilitate surgical resection. Its success requires collaboration between the interventional radiologist, the surgeon, and the ophthalmologist.

Comorbid pulmonary disease and risk of community-acquired pneumonia in COPD patients.

SETTING: Risk of pneumonia in chronic obstructive pulmonary disease (COPD) patients due to comorbid pulmonary disease is not well understood. OBJECTIVE: To compare factors associated with risk of community-acquired pneumonia (CAP) in COPD patients for those with and without lung cancer, bronchiectasis and/or history of active tuberculosis. DESIGN: Retrospective chart review of patients diagnosed with COPD (forced expiratory volume in 1 second/forced vital capacity < 0.70) between 2006 and 2010, including patient characteristics, occurrence of CAP and type of inhalation treatment. Pneumonia-free survivals were assessed using Kaplan-Meier curves. Factors associated with CAP were assessed using Cox's proportional hazard regression and expressed as adjusted hazard ratios (aHRs) with 95% confidence intervals (CIs). RESULTS: Of 2630 patients, 402 (15.3%) developed CAP during follow-up. The likelihood of CAP increased with increased age (aHR 1.03, 95%CI 1.02-1.04), lower body mass index (BMI; aHR 0.97, 95%CI 0.95-1.00), lung cancer (aHR 3.81, 95%CI 2.88-5.05), bronchiectasis (aHR 2.46, 95%CI 1.70-3.55) and inhaled corticosteroid (ICS) containing treatment (aHR 1.60, 95%CI 1.30-1.96). ICS-containing treatment was associated with increased risk of CAP only for patients without comorbid pulmonary disease (aHR 1.68, 95%CI 1.30-2.17). CONCLUSION: For COPD patients: 1) increased age, low BMI, lung cancer and bronchiectasis may increase the risk of CAP, and 2) without respiratory comorbid disease, ICS use increases the risk of CAP.

Increasing directly observed therapy related to improved tuberculosis treatment outcomes in Taiwan.

SETTING: Directly observed therapy (DOT) is a core element of tuberculosis (TB) care and control efforts. In Taiwan, DOT was implemented in 2006, when the Stop TB Strategy was adopted as a national policy. OBJECTIVE: To quantify DOT among patients on anti-tuberculosis treatment and measure the association between proportion of DOT and TB treatment outcomes at a national level in Taiwan. DESIGN: We analyzed data prospectively collected on all new pulmonary TB cases reported to the national web-based registry between 1 January 2007 and 30 June 2008. We compared treatment outcomes and proportion of DOT in multivariable analyses. RESULTS: Among 11,528 patients initiating anti-tuberculosis treatment, the proportion of days during which an official DOT observer witnessed treatment was >60% for 5150 (45%) patients and ≤60% for 4601 (40%) patients, whereas for 1777 (15%) patients no days of DOT were recorded. Being older, male, having positive bacteriology results and a non-World Health Organization recommended treatment regimen at baseline were independently related to unsuccessful treatment outcomes and mortality. A dose-response effect was found between proportion of DOT and these outcomes. CONCLUSION: These findings highlight the importance of ensuring universal DOT in improving treatment outcomes among new pulmonary TB patients.

Latent tuberculosis infection treatment for prison inmates: a randomised controlled trial.

SETTING: A prison in northern Taiwan. OBJECTIVE: To compare safety and the completion rate of the 4-month daily rifampicin regimen (4R) vs. the standard 6-month daily isoniazid regimen (6H) for latent tuberculosis infection (LTBI) in prison inmates. DESIGN: This was an open-label randomised trial among human immunodeficiency virus negative male inmates. Inmates without active tuberculosis (TB) who tested positive for both the tuberculin skin test and QuantiFERON®-TB Gold In-Tube were eligible, but those with baseline glutamic pyruvic transaminase (GPT) levels ≥ 120 U/l, bilirubin levels ≥ 2.4 U/l or a platelet count < 150 k/mm(3) were excluded. The primary endpoint was any adverse event that resulted in discontinuation of LTBI treatment. RESULTS: Participants (n = 373; 14% hepatitis B surface antigen positive, 21% anti-hepatitis C virus [HCV] positive) were randomised (stratified by hepatitis B virus, HCV status and 2-year prison term) to receive either 4R or 6H under directly observed treatment. The 4R group (n = 190) was less likely to experience an adverse event leading to discontinuation of treatment (2% vs. 12%, P < 0.001 for all adverse events; 0% vs. 8%, P < 0.001 for hepatotoxicity), and more likely to complete LTBI treatment (86% vs. 78%, P = 0.041), compared with the 6H group (n = 183). CONCLUSIONS: 4R is safer and has a higher completion rate than 6H as treatment for LTBI among male prison inmates.

NTP toxicity studies of toxicity studies of 2,4-decadienal (CAS No. 25152-84-5) administered by gavage to F344/N Rats and B6C3F1 mice.

2,4-Decadienal is used as a synthetic flavoring and fragrance material and has been evaluated as a corrosion inhibitor for steel in oil field operations. 2,4-Decadienal was nominated by the National Cancer Institute for toxicity testing because the dienaldehydes occur naturally in a variety of foods and food components, are used as food additive/flavoring agents, and the potential for human exposure is high. In the toxicity studies, male and female F344/N rats and B6C3F1 mice received 2,4-decadienal (at least 93% pure) in corn oil by gavage for 2 weeks or 3 months. Genetic toxicology studies were conducted in Salmonella typhimurium, rat and mouse bone marrow cells, and mouse peripheral blood erythrocytes. In the 2-week studies, groups of five male and five female rats and mice received 2,4-decadienal in corn oil by gavage at doses of 0, 45, 133, 400, 1,200, or 3,600 mg 2,4-decadienal/kg body weight 5 days per week for 16 days. All animals in the 3,600 mg/kg groups were found dead or sacrificed moribund by day 3 (rats) or day 9 (mice). One 133 mg/kg female rat was found dead on day 8, and one male and one female mouse in the 1,200 mg/kg groups were found dead on days 12 and 16, respectively. At 1,200 mg/kg, treatment-related ulceration of the forestomach was observed in male and female rats and mice. Focal necrosis of the forestomach occurred in a 1,200 mg/kg female mouse. Mean body weights of all 1,200 mg/kg groups were less than those of the vehicle controls, and 1,200 mg/kg female mice lost weight during the study. Diarrhea, lethargy, abnormal breathing (rats), and thinness (mice) occurred in the 1,200 and 3,600 mg/kg groups. Gross lesions seen at necropsy included ulcerations of the forestomach in 1,200 mg/kg rats and 1,200 and 3,600 mg/kg mice. Adhesions involving the stomach and other abdominal organs were also seen in 1,200 and 3,600 mg/kg mice. In the 3-month studies, groups of 10 male and 10 female rats and mice received 2,4-decadienal in corn oil by gavage at doses of 0, 50, 100, 200, 400, or 800 mg 2,4-decadienal/kg 5 days per week for 14 weeks. No chemical-related deaths occurred. Mean body weights of 400 mg/kg male rats and 800 mg/kg male and female rats and male mice were significantly less than those of the vehicle controls. Dosed male and female rats were lethargic after week 7; the severity of the lethargy was dose related. There were changes in the leukon of dosed rats compared to vehicle control rats characterized by decreased leukocyte, lymphocyte, and eosinophil counts and increased neutrophil counts. Spleen weights of 800 mg/kg female rats and thymus weights of 400 and 800 mg/kg female rats were significantly less than those of the vehicle controls. Thymus, spleen, testis, cauda epididymis, and epididymis weights of 800 mg/kg male rats were less than those of the vehicle controls. The incidences of epithelial hyperplasia of the forestomach were significantly greater in 400 and 800 mg/kg male and female rats, 200, 400, and 800 mg/kg male mice, and 800 mg/kg female mice than in the vehicle controls. Incidences of epithelial degeneration of the forestomach were significantly increased in 800 mg/kg rats and the incidence of chronic active inflammation of the forestomach was significantly increased in 800 mg/kg female rats. Incidences of exudate and olfactory epithelial atrophy of the nose were significantly increased in 800 mg/kg male rats, and incidences of olfactory epithelial necrosis occurred in 200 mg/kg or greater mice. Olfactory epithelial hydropic degeneration occurred in a single female mouse from the 100 mg/kg group. 2,4-Decadienal was not mutagenic in any of several strains of S. typhimurium tested with and without liver S9 activation enzymes. Acute bone marrow micronucleus tests in laboratory rodents administered 2,4-decadienal by intraperitoneal injection yielded mixed results. In male rats, a single injection of 2,4-decadienal gave a positive response, but no confirmatory trial was conducted. In male mice, a standard three-injection bone marrow micronucleus experiment yielded negative results but a 48-hour bone marrow analysis after a single dose of 600 mg/kg revealed a small but statistically significant increase in micronucleated polychromatic erythrocytes. Analysis of peripheral blood erythrocytes in these same mice also showed a dose-related increase in micronucleated polychromatic cells, but the increase was insufficient for a positive call and the results of the acute micronucleus assays in mice were judged to be equivocal overall. No increase in the frequency of micronucleated normochromatic erythrocytes was seen in peripheral blood of male or female mice administered 2,4-decadienal by gavage for 3 months. In summary, 2,4-decadienal administration caused decreased body weights and increased incidences of forestomach lesions in the 3-month studies in rats and mice. In addition, treatment-related lesions of the olfactory epithelium were observed in male rats and male and female mice. The no-observed-adverse-effect level was determined to be 100 mg/kg in rats and mice. 2,4-Decadienal was not mutagenic in vitro or in vivo. Synonyms: 2,4-De; deca-2,4-dienal; trans,trans-2,4-decadienal; trans,trans-2,4-decadien-1-al; heptenyl acrolein; RIFM#77-102.

Contact investigation for tuberculosis in Taiwan contacts aged under 20 years in 2005.

OBJECTIVE: To measure the tuberculosis (TB) incidence rate and assess the relative risk of TB disease in contacts based on the tuberculin skin test (TST) and sputum status of index cases. DESIGN: All contacts aged <20 years who were exposed to a TB case in 2005 were cross-matched using an electronic surveillance system to estimate TB incidence over a 24-month follow-up period. RESULTS: Among 6959 contacts there were 67 secondary cases (1%). The incidence was highest in the first year after exposure and decreased by half in the second year (P = 0.001). The relative risks of developing TB in contacts aged 0-4, 5-9, 10-14 and 15-19 years were respectively 325, 209, 337 and 53 times greater than for the general population. The hazard ratio of developing TB among contacts with a TST ≥ 15 mm induration was 12 times higher than for those with a TST < 5 mm (P = 0.003). CONCLUSIONS: The relative risk of developing TB disease within 24 months of exposure was approximately 200-300 times greater for contacts aged <15 years. The majority developed TB within 12 months of exposure.

Phosphorylation of focal adhesion kinase on tyrosine 194 by Met leads to its activation through relief of autoinhibition.

Focal adhesion kinase (FAK) has a crucial role in integration of signals from integrins and growth factor receptors. In this study, we demonstrate that growth factor receptors including hepatocyte growth factor receptor Met, epidermal growth factor receptor, and platelet-derived growth factor receptor directly phosphorylate FAK on Tyr194 in the FERM domain (band 4.1 and ezrin/radixin/moesin homology domain). Upon binding to Met or phosphoinositides, FAK may undergo conformational changes, which renders Tyr194 accessible for phosphorylation. Substitution of Tyr194 with Phe significantly suppresses the activation of FAK by Met. In contrast, substitution of Tyr194 with Glu (Y194E substitution) leads to constitutive activation of FAK. The phosphorylation of FAK on Tyr194 may cause conformational changes in the FERM domain, which disrupts the intramolecular inhibitory interaction between the FERM and kinase domains of FAK. Moreover, substitution of the basic residues in the (216)KAKTLRK(222) patch in the FERM domain with Ala antagonizes the effect of the Y194E substitution on FAK activation, thus suggesting that the interactions between the phosphorylated Tyr194 and the basic resides in the (216)KAKTLRK(222) patch may allow FAK to be activated through relief of its autoinhibition. Collectively, this study provides the first example to explain how FAK is activated by receptor tyrosine kinases.

Differential phosphorylation of the docking protein Gab1 by c-Src and the hepatocyte growth factor receptor regulates different aspects of cell functions.

The docking protein Grb2-associated binder1 (Gab1) has a central role in the integration of the growth-factor signaling. In this study, we aimed to examine the significance of Src-mediated Gab1 phosphorylation in the hepatocyte growth factor (HGF) signaling. Using both mutagenesis and mass spectrometry approaches, Y242, Y259, Y317, Y373 and Y627 of Gab1 were identified to be phosphorylated by c-Src. It is interesting to note that the binding of the tyrosine phosphatase SHP2 to the Y627 antagonized the effect of c-Src on the phosphorylation of the other four tyrosine residues. Moreover, the tyrosine residues predominantly phosphorylated by c-Src were different from those predominantly phosphorylated by the HGF receptor. Gab1 overexpression potentiated both mitogenic and motogenic activities of HGF. However, a Gab1 mutant with substitutions of the Src phosphorylation sites (Y242, Y259, Y317 and Y373) failed to promote HGF-induced DNA synthesis, but retained its ability to facilitate HGF-induced chemotaxis. Taken together, our results not only suggest that the phosphorylation of Gab1 by c-Src is important for HGF-induced DNA synthesis, but also provide an example to illustrate how a docking protein (for example, Gab1) is differentially phosphorylated by c-Src and a receptor tyrosine kinase to emanate full spectrum of signals to the downstream.

Age-specific cut-offs for the tuberculin skin test to detect latent tuberculosis in BCG-vaccinated children.

OBJECTIVE: To evaluate the effect of neonatal vaccination with bacille Calmette-Guérin (BCG) on tuberculin skin test (TST) reactivity over time and to define the optimal age-specific induration cut-offs to detect latent tuberculosis infection (LTBI). DESIGN: TSTs were performed on 783 children aged 3 months to 14 years who had received neonatal BCG. The estimated annual risk of LTBI was derived from TSTs administered to 2504 children aged 7 years who lacked BCG scars. Goodness-of-fit analysis was used to determine the optimal age-specific cut-off values. RESULTS: The effect of neonatal BCG on TST induration waned with age, reaching a nadir at age 6-7 years. This was followed by a rise in TST reactivity. The optimal age-specific TST cut-off values for the detection of LTBI was estimated to be respectively 21, 18, 13 and 10 mm at ages 0-1, 2-3, 4-5 and 6-7 years. There was a close correlation between these new cut-off values with the estimated risk of LTBI for the first 7 years of life (r = 0.93, P < 0.001). CONCLUSIONS: The effect of neonatal BCG on TST gradually declines over the first 7 years of life. Our proposed new age-specific TST induration cut-off values could help differentiate between response to BCG and LTBI in young children.

Evaluation of a urinary metanephrines reagent kit: an automated approach.

INTRODUCTION: We report the results of a laboratory evaluation of the BioRad Urinary Metanephrines Reagent Kit. The test was designed for the quantitative measurement of normetanephrine and metanephrine in urine by high performance liquid chromatography. The kit was evaluated in view of improving assay reliability and specificity as compared to the manual method based on cation exchange chromatography and spectrophotometry. METHODS: Performance was evaluated for precision, linearity, accuracy, sensitivity and detection limit based on National Committee on Clinical Laboratory Standards (NCCLS) protocols. Analytical precision was evaluated using commercial controls and patient sample. Accuracy was evaluated by assessing recovery. Linearity was determined using aqueous standards. RESULTS: The within-run coefficient of variation (CV) for metanephrine and normetanephrine were 1.9 percent and 2.4 percent (low control); 4.2 percent and 3.5 percent (high control); 3.8 percent and 3.3 percent (patient sample), respectively. The between-day precisions were 3.8 percent and 4.3 percent (low control); and 5.5 percent and 3.7 percent (high control) for metanephrine and normetanephrine, respectively. The linearity curve showed metanephrine and normetanephrine to be linear with concentrations, to at least 1,600 microgramme per litre and 2,000 microgramme per litre, respectively. Analytical recovery averaged 102 percent for metanephrine and 95 percent for normetanephrine. Levels as low as 23 microgramme per litre normetanephrine and 10 microgramme per litre metanephrine were measured with this method. The detection limit was 3.3 microgramme per litre for metanephrine. CONCLUSION: The performance characteristics of automated sample preparation and auto-injection facilitate handling of larger number of samples as well as improve assay reliability.

Pain behaviours in Extremely Low Gestational Age infants.

BACKGROUND: To date, there are over 40 infant pain measures. Despite this plethora of measures, only 8 have included preterm infants and only 2 have included Extremely Low Gestational Age (ELGA; infants <28 weeks GA) in their development. Without reliable, valid and clinically useful indicators for procedural pain in ELGA infants, clinicians have no means to interpret the responses from an immature infant who may respond differently from infants of older GA. OBJECTIVE: To examine the physiological, behavioural and biochemical responses to painful and non-painful procedures in ELGA infants and the influence of GA and sex. DESIGN/METHODS: A prospective crossover design with 50 ELGA infants from one Canadian tertiary level NICU was conducted. Infants were assessed in random order during standardized painful (heel lance) and non-painful (diaper change) procedures. Physiological (heart rate, oxygen saturation) and behavioural (facial and body movement) indicators were continuously collected during 4 phases of the procedures. Biochemical (salivary cortisol) indicators were collected immediately before and 20 min following the procedures. RESULTS: Four facial actions (brow bulge, eye squeeze, nasolabial furrow, vertical mouth stretch) increased immediately following the heel lance. There were no specific changes in physiological, body movement or cortisol indicators following the heel lance. ELGA infants demonstrated greater body movements during the diaper change, which may reflect immature motor coordination. No differences in pain responses were found for infants born between 23-25 6/7 weeks GA and those between 26-28 weeks GA. Similarly, no gender differences were found. CONCLUSIONS: Changes in 4 facial actions were the most sensitive indicators of pain in ELGA infants. This finding is consistent with existing measures where facial actions are the most prominent pain indicators. Specific body movements such as those included in NIDCAP, may provide more information about pain in ELGA infants. Movements such as hand-on-face, finger splaying, fisting, arching or yawning need to be examined in future research.

Carbon nanotube thermal interface material for high-brightness light-emitting-diode cooling.

Aligned carbon nanotube (CNT) arrays were fabricated from a multilayer catalyst configuration by microwave plasma-enhanced chemical vapor deposition (PECVD). The effects of the thickness and annealing of the aluminum layer on the CNT synthesis and thermal performance were investigated. An experimental study of thermal resistance across the CNT array interface using the modified ASTM D5470 standard was conducted. It was demonstrated that the CNT-thermal interface material (CNT-TIM) reduced the thermal interfacial resistance significantly compared with the state-of-art commercial TIM. The optimized thermal resistance of the CNT arrays is as low as 7 mm(2) K W(-1). The light performance of high-brightness light-emitting diode (HB-LED) packages using the aligned CNT-TIM was tested. The results indicated that the light output power was greatly improved with the use of the CNT-TIM. The usage of the CNT-TIM can be also extended to other microelectronics thermal management applications.

Induction of thyroid and liver tumors by chronic exposure to 2-methylimidazole in F344/N rats and B6C3F1 mice.

2-Methylimidazole (2MI) has been identified as a by-product of fermentation and is detected in foods and mainstream and side-stream tobacco smoke. It is used in the manufacture of pharmaceuticals, photographic chemicals, dyes and pigments, agricultural chemicals, and rubber. Carcinogenicity studies of 2MI were conducted because of its high potential for human exposure and a lack of carcinogenicity data. Groups of male and female Fischer 344/N rats were fed diets containing 0, 300, 1,000, or 3,000 ppm (males) or 0, 1,000, 2,500, or 5,000 ppm (females) 2MI for 106 weeks and groups of male and female B6C3F1 mice were fed 0, 625, 1,250, or 2,500 ppm 2MI for 105 weeks. Animals in each group were sacrificed at 8 days, 14 weeks, and 6 months for determinations of serum thyroid hormone and liver enzyme levels and histopathological examinations and at 2 years for evaluations of neoplastic lesions. In rats, 2MI administration reduced serum thyroxine and triiodothyronine and increased thyroid stimulating hormone levels. 2MI administration also increased total hepatic UDP-glucuronosyltransferase levels. At 2 years, the incidences of thyroid follicular cell hyperplasia, adenoma or carcinoma (combined), as well as follicular mineralization were increased. The incidences of hepatocellular adenoma or carcinoma (combined) in the two highest dose groups of males and females were also increased. The incidences of mixed cell focus in males and females were also significantly increased. In mice, the incidences of thyroid follicular cell hypertrophy and hyperplasia were significantly increased in the high dose males and females. The incidence of thyroid follicular cell adenoma in the 2,500 ppm males was significantly greater than that in the control group. The incidences of hepatocellular adenoma or carcinoma (combined) were significantly increased in all exposed groups of males and in the 2,500 ppm females. Significant increases in incidences were also observed in spleen hematopoietic cell proliferation in both sexes and bone marrow hyperplasia, chronic active inflammation of the epididymis, sperm granuloma, and germinal epithelial atrophy of the testis in males. Under these experimental conditions, carcinogenic activity of 2MI was demonstrated in male and female rats and mice.

Toxicity and carcinogenicity studies of 4-methylimidazole in F344/N rats and B6C3F1 mice.

4-Methylimidazole (4MI) is used in the manufacture of pharmaceuticals, photographic chemicals, dyes and pigments, cleaning and agricultural chemicals, and rubber. It has been identified as a by-product of fermentation in foods and has been detected in mainstream and side stream tobacco smoke. 4MI was studied because of its high potential for human exposure. Groups of 50 male and 50 female F344/N rats were fed diets containing 0-, 625-, 1,250-, or 2,500 ppm 4MI (males) or 0-, 1,250-, 2,500-, or 5,000 ppm 4MI (females) for 106 weeks. Based on the food consumption the calculated average daily doses were approximately 30, 55, or 115 mg 4MI/kg body weight to males and 60, 120, or 250 mg 4MI/kg to females. Survival of all exposed groups of males and females was similar to that of the control groups. The mean body weights of males in the 1,250- and 2,500 ppm groups and females in the 2,500- and 5,000 ppm groups were less than those of the control groups throughout the study. Feed consumption by 5,000 ppm females was less than that by the controls. Clonic seizures, excitability, hyperactivity, and impaired gait were observed primarily in 2,500- and 5,000 ppm females. The incidence of mononuclear cell leukemia in the 5,000 ppm females was significantly greater than that in the controls. The incidences of hepatic histiocytosis, chronic inflammation, and focal fatty change were significantly increased in all exposed groups of male and female rats. The incidences of hepatocellular eosinophilic and mixed cell foci were significantly increased in 2,500 ppm males and 5,000 ppm females. Groups of 50 male and 50 female B6C3F1 mice were fed diets containing 0-, 312-, 625-, or 1,250 ppm 4MI for 106 weeks. Based on the food consumption the calculated average daily doses were approximately 40, 80, or 170 mg 4MI/kg body weight to males and females. Survival of all exposed groups of males and females was similar to that of the control groups. Mean body weights of males and females in the 1,250 ppm groups and that in the 312- and 625 ppm females were less than those of the control groups. Feed consumption by exposed groups of male and female mice was similar to that by the controls. The incidences of alveolar/bronchiolar adenoma in all exposed groups of females, alveolar/bronchiolar carcinoma in 1,250 ppm males, and alveolar/bronchiolar adenoma or carcinoma (combined) in 1,250 ppm males and 625- and 1,250 ppm females were significantly greater than those in the control groups. The incidence of alveolar epithelial hyperplasia was significantly increased in the 1,250 ppm females. 4MI is carcinogenic inducing alveolar/bronchiolar adenoma and carcinoma in male and female mice. 4MI may also induce mononuclear cell leukemia in female rats.

Functional and pharmacokinetic outcomes after a single intravenous infusion of recombinant human erythropoietin in patients with malignant extradural spinal cord compression.

AIMS: To determine the cerebrospinal fluid concentrations and the functional and pain outcomes after a single intravenous infusion of erythropoietin at the start of a standard radiotherapy and steroid protocol. MATERIALS AND METHODS: Ten paraparetic patients with malignant extradural spinal cord compression who were eligible for radiotherapy, lumbar puncture and intravenous epoetin alpha were enrolled. The patients received epoetin alpha 1500 IU/kg intravenously over 30 min followed by a standardised dexamethasone and radiotherapy protocol. A lumbar puncture and venipuncture were carried out 24-30 h after the epoetin alpha infusion. The patients were followed closely at defined intervals. RESULTS: Erythropoietin was detectable in the cerebrospinal fluid in all eight patients sampled (median 92.5 mIU/ml, range 17.8-214.0 mIU/ml). Before treatment, eight patients were non-ambulatory and two patients were ambulatory with assistance. After treatment, eight (80%, 95% confidence interval [CI] 44-97%) improved at least one functional class and recovered or maintained ambulation. Five of seven patients (71%; 95% CI 29-96%) with objective sensory deficits and one of seven (14%; 95% CI 0-58%) catheter-dependent patients recovered. Overall, 78% (95% CI 40-97%) had a pain response. CONCLUSIONS: After an intravenous infusion of epoetin alpha, radiotherapy and steroids, high concentrations of erythropoietin were detectable in the cerebrospinal fluid. Patients with malignant extradural spinal cord compression showed encouraging improvements in neurological function and pain.

NTP technical report on the toxicity studies of 2- and 4-Methylimidazole (CAS No. 693-98-1 and 822-36-6) administered in feed to F344/N rats and B6C3F1 mice.

[Structure-see text] 2-Methylimidazole and 4-methylimidazole are intermediate/starting materials or components in the manufacture of pharmaceuticals, photographic and photothermographic chemicals, dyes and pigments, agricultural chemicals, and rubber; these chemicals have been identified as undesirable by-products in several foods and have been detected in mainstream and sidestream tobacco smoke. The National Cancer Institute nominated 2- and 4-methylimidazole as candidates for toxicity and carcinogenicity studies. Toxicity studies were carried out in male and female F344/N rats and B6C3F1 mice. Animals were exposed to 2- or 4-methylimidazole in feed for 15 days or 14 weeks; clinical pathology studies were conducted in the 14-week studies on days 8, 29, and 86 and at week 14. Genetic toxicity studies were conducted in Salmonella typhimurium, rat and mouse bone marrow, and mouse peripheral blood. Groups of five male and five female rats and mice were fed diets containing 0, 1,200, 3,300, or 10,000 ppm 2-methylimidazole (equivalent to average daily doses of approximately 115, 290, or 770 mg 2-methylimidazole/ kg body weight to rats; 220, 640, or 2,100 mg/kg to male mice; 300, 800, or 2,400 to female mice) for 15 days. Groups of five male and five female rats and mice were fed diets containing 0, 300, 800, or 2,500 ppm 4-methylimidazole (equivalent to average daily doses of approximately 30, 80, or 220 mg/kg for rats and 65, 170, or 500 mg/kg for mice) for 15 days. In the 15-day 2-methylimidazole studies, all animals survived to the end of the studies. The mean body weights of 10,000 ppm male rats and female mice were significantly less than those of the controls. Feed consumption by 10,000 ppm male and female rats was reduced. Enlarged thyroid glands were observed in 3,300 and 10,000 ppm male and female rats. The incidences of diffuse hyperplasia of follicular cells of the thyroid gland in 3,300 and 10,000 ppm male and female rats and pars distalis hypertrophy of the pituitary gland in 3,300 and 10,000 ppm males and 10,000 ppm females were increased compared to the controls. In all exposed groups of male and female mice, the incidences and severities of follicular cell hypertrophy of the thyroid gland and the severities of hematopoietic cell proliferation of the spleen generally increased with increasing exposure concentration. In the 4-methylimidazole studies, all animals survived to the end of the studies, and there were no significant differences in mean body weights, clinical findings, organ weights, or gross or microscopic lesions between exposed and control groups. Groups of 10 male and 10 female rats and mice were fed diets containing 0, 625, 1,250, 2,500, 5,000, or 10,000 ppm 2- or 4-methylimidazole (equivalent to average daily doses of approximately 40, 80, 160, 300, or 560 mg/kg 2- or 4-methylimidazole to rats; and 100, 165, 360, 780, or 1,740 mg/kg 2-methylimidazole or 100, 240, 440, 915, or 1,840 mg/kg 4-methylimidazole to male mice; and 90, 190, 400, 800, or 1,860 mg/kg 2-methylimidazole or 110, 240, 540, 1,130, or 3,180 mg/kg 4-methylimidazole to females) for 14 weeks. All animals survived to the end of the 14-week 2-methylimidazole studies. Compared to the controls, the mean body weights were significantly decreased in groups of male rats and mice exposed to 2,500 ppm or greater and in 5,000 and 10,000 ppm female rats and mice. In rats, 2-methylimidazole induced a transient erythrocytosis in females and a minimal, exposure concentration-related, microcytic, normochromic, nonresponsive anemia. 2-Methylimidazole increased thyroid-stimulating hormone concentrations and decreased thyroxine and triiodothyronine concentrations of male and female rats in an exposure concentration-related manner. 2-Methylimidazole induced a mild to moderate, exposure concentration-related, macrocytic, hyperchromic, responsive anemia in mice. Triiodothyronine concentrations were increased in exposed male and female mice, and thyroxine concentrations were decreased in exposed females. Relative to the control groups, clinical chemistry evaluations on day 29 and at week 14 identified decreases in alanine aminotransferase concentrations and total protein and albumin concentrations of rats. In the 2-methylimidazole studies, absolute spleen weights were significantly increased in all exposed groups of male rats. The heart and liver weights were increased in all exposed groups of male mice, as were the spleen weights of female mice exposed to 2,500 ppm or greater. Spermatid heads per testis and mean spermatid count were significantly decreased in 10,000 ppm male rats. The estrous cycle of 10,000 ppm female rats was significantly increased. Gross pathology observations included enlarged thyroid glands, small uteri, and mottled spleen in 5,000 and 10,000 ppm mice. The incidences of diffuse follicular cell hyperplasia of the thyroid gland were significantly increased in male rats exposed to 1,250 ppm or greater and female rats exposed to 2,500 ppm or greater. The incidence of testicular degeneration was significantly increased in 10,000 ppm male rats, and two males in the 10,000 ppm group had follicular cell adenoma of the thyroid gland. In mice, there were generally significant increases in the incidences of follicular cell hypertrophy of the thyroid gland, hematopoietic cell proliferation of the spleen, and hemosiderin pigmentation of the renal tubule in males exposed to 1,250 ppm or greater and females exposed to 2,500 ppm or greater. In the 14-week 4-methylimidazole studies, one 10,000 ppm male mouse was found dead during week 4, and seven 10,000 ppm female mice were found dead during weeks 1 and 2. Mean body weights were significantly less than those of the controls for male rats exposed to 2,500 ppm or greater, 5,000 and 10,000 ppm female rats, male mice exposed to 1,250 ppm or greater, and all exposed groups of female mice. Reduced feed consumption was observed in 5,000 and 10,000 ppm male and female rats. Clinical findings included nasal/eye discharge, ruffled fur, thinness, ataxia, and abnormal breathing in rats, and ruffled fur and dull coats in female mice. On days 29 and 82, functional observations in 5,000 and 10,000 ppm rats included labored or increased respiration, mild tremors, walking on tiptoes, hunched posture, piloerection, crouching over, impaired coordination of movement, ataxia, and pupillary constriction. 4-Methylimidazole induced a transient erythrocytosis and a minimal, exposure concentration-related, microcytic, normochromic, nonresponsive anemia in male and female rats. Clinical chemistry evaluations generally showed a cholestatic effect in exposed male and female rats. At week 14, there was a significant decrease in total protein and albumin concentrations of female rats exposed to 5,000 or 10,000 ppm. In mice, 4-methylimidazole induced a macrocytic, hyperchromic, responsive anemia and, particularly in males, increases in triiododthyronine concentrations and transient decreases in thyroxine concentrations. In the 4-methylimidazole studies, the liver weights of male rats exposed to 2,500 ppm or greater were significantly increased; spleen weights of female rats exposed to 2,500 ppm or greater were decreased. The absolute liver weight was decreased in 10,000 ppm male mice, and relative weights were significantly increased in all exposed groups of mice. In female mice, there was a significant decrease in the absolute weights and increase in the relative weights of the heart, right kidney, and liver in groups exposed to 2,500 ppm or greater. The epididymal spermatozoal concentration was significantly increased in 5,000 ppm male rats. Gross pathology observations included pale livers in male rats exposed to 2,500 ppm or greater and small testes and uteri in 10,000 ppm male and female rats. Microscopic analysis identified significantly increased incidences of cytoplasmic hepatocyte vacuolization of the liver of male rats exposed to 2,500 ppm or greater and 10,000 ppm female rats, hypospermia of the epididymis in 10,000 ppm male rats, atrophy and inflammation of the prostate gland in 10,000 ppm male rats, and degeneration of the testes in 5,000 and 10,000 ppm male rats. 2-Methylimidazole and 4-methylimidazole were negative in the S. typhimurium mutation assay when tested in strains TA97, TA98, TA100, and TA1535, with and without S9 activation enzymes. Testing of 2-methylimidazole in vivo for induction of chromosomal damage, as measured by micronucleated erythrocyte frequency, produced mixed results. When administered by intraperitoneal injection three times at 24-hour intervals, 2-methylimidazole produced negative results in bone marrow micronucleus tests in rats and mice. However, in the 14-week study of 2-methylimidazole, a significant exposure-related increase in the frequency of micronucleated normochromatic erythrocytes was noted in peripheral blood of male and female mice. In vivo, 4-methylimidazole produced uniformly negative results in three-injection bone marrow micronucleus tests in rats and mice and in 14-week peripheral blood micronucleus tests in male and female mice.

Haemophilus influenzae type b meningitis with subdural effusion: a case report.

Haemophilus influenzae type b causes invasive infection in children under 2 years of age. The disease may be complicated with hearing impairment, lowered learning ability, and other neurologic sequelae. The incidence of invasive H. influenzae type b has declined dramatically after the introduction of routine administration of protein-conjugated H. influenzae type b vaccine in the United States and some other countries. Because of its low incidence in Taiwan, many clinicians are not familiar with the initial symptoms and management of H. influenzae type b. This case report describes a 7-month-old H. influenzae type b meningitis patient who had initial presentations of prolonged intermittent fever and vague neurologic signs. Left peripheral facial palsy with hearing loss in left ear and bilateral frontal subdural effusion developed during the first 5 days of cefotaxime therapy. Betamethasone was then given for 4 days to relieve the severe inflammation. Drug-induced fever was observed after 11 days of antibiotic use and subsided with prednisolone treatment. Left ear hearing impairment persisted during the follow-up period, but the children did not experience other significant development delay.

Evaluation of impulse noise criteria using human volunteer data.

Four impulse noise auditory injury criteria adopted by NATO countries, namely, the MIL-STD-1474D (USA), Pfander (Germany), Smoorenburg (Netherlands), and L(Aeq8) (France), are evaluated against human volunteer data. Data from subjects wearing single-hearing protection exposed to increasing blast overpressure effects were obtained from tests sponsored by the US Army Medical Research and Material Command. Using logistic regression, the four criteria were each correlated with the test data. The analysis shows that all four criteria are overly conservative by 9.6-21.2 dB for the subjects as tested. The MIL-STD-1474D for single-hearing protection is 9.6 dB lower than the observed injury threshold for 95% protection with 95% confidence for this particular group of subjects as tested. Similar conclusions can be drawn for the other three criteria.