A Global Perspective on H9N2 Avian Influenza Virus.

H9N2 avian influenza viruses have become globally widespread in poultry over the last two decades and represent a genuine threat both to the global poultry industry but also humans through their high rates of zoonotic infection and pandemic potential. H9N2 viruses are generally hyperendemic in affected countries and have been found in poultry in many new regions in recent years. In this review, we examine the current global spread of H9N2 avian influenza viruses as well as their host range, tropism, transmission routes and the risk posed by these viruses to human health.

Application of a redox gradostat reactor for assessing rhizosphere microorganism activity on lambda-cyhalothrin.

Bacterial activity on pesticides can lead to decreased toxicity or persistence in aquatic systems. Rhizosphere activity is difficult to measure in situ. To mimic rhizosphere properties of the soft rush, Juncus effusus, a single-stage gradostat reactor was developed to study cycling of lambda-cyhalothrin by rhizobacteria and the effects of Fe(III) and citrate, both common in wetland soil, on lambda-cyhalothrin degradation. Redox gradient changes, greater than ± 10 mV, were apparent within days 5-15 both in the presence and absence of ferric citrate. Through the production of a redox gradient (p < 0.05) by rhizobacteria and the ability to measure pesticide loss over time (p < 0.05), reactors were useful in expanding knowledge on this active environment.

Comparison of glycated albumin and hemoglobin A(1c) levels in diabetic subjects on hemodialysis.

Glycated albumin is thought to more accurately reflect glycemic control in diabetic hemodialysis patients than hemoglobin A(1c) because of shortened red cell survival. To test this, glycated hemoglobin and albumin levels were measured in blood samples collected from 307 diabetic subjects of whom 258 were on hemodialysis and 49 were without overt renal disease. In diabetic subjects with renal disease, relative to those without, the mean serum glucose and glycated albumin concentrations were significantly higher while hemoglobin A(1c) tended to be lower. The glycated albumin to hemoglobin A(1c) ratio was significantly increased in dialysis patients compared with the controls. Hemoglobin A(1c) was positively associated with hemoglobin and negatively associated with the erythropoietin dose in hemodialysis patients, whereas these factors and serum albumin did not significantly impact glycated albumin levels. Using best-fit multivariate models, dialysis status significantly impacted hemoglobin A(1c) levels without a significant effect on glycated albumin. Our results show that in diabetic hemodialysis patients, hemoglobin A(1c) levels significantly underestimate glycemic control while those of glycated albumin more accurately reflect this control.

The role of ultrasound in the detection of cervical lymph node metastases in clinically N0 squamous cell carcinoma of the head and neck.

Nodal involvement is the most important prognostic factor in head and neck squamous cell carcinoma (HNSCC) of mucosal origin. The presence of a single ipsilateral or contralateral metastatic node reduces survival by 50% and bilateral disease by a further 50%. The management of N+ HNSCC is relatively clear-cut. By contrast, the investigation and treatment of patients with clinically N0 disease is controversial. Most institutions electively treat the neck with surgery or radiotherapy because the risk of occult metastases is over 20%, even though it will be unnecessary in the majority of cases. In this situation the main purpose of staging would be to assess those nodes that are not going to be removed. However, the optimal management of the clinically N0 neck remains controversial and there is growing interest in a more conservative approach. Research is now directed toward finding a method of staging sensitive enough to bring the risk of occult metastases below 20%. High spatial resolution, ease of multiplanar scanning, power Doppler and the ability to perform guided fine-needle aspiration for cytology give ultrasound (US) an advantage over other imaging techniques.

Phase II trial of toremifene in androgen-independent prostate cancer: a Penn cancer clinical trials group trial.

Toremifene has antiestrogenic and estrogenic properties in vitro and in vivo. In addition, it may have antiangiogenesis and antimicrotubule properties at higher doses. Studies have demonstrated the efficacy of this agent in the treatment of metastatic breast cancer. We performed a phase II trial of toremifene in patients with androgen-independent prostate cancer (AIPC). Patients with an increasing prostate-specific antigen level despite castrate testosterone levels and antiandrogen withdrawal were eligible. Patients could not have received prior salvage hormonal therapy or chemotherapy. Patients received toremifene at 300 mg/m2/d orally (maximum dose 640 mg/d). Fifteen patients were treated. Patients received treatment for a median of 13 weeks (range, 4-30 weeks). The median age was 72 years (range, 58-80 years). The median Eastern Cooperative Oncology Group performance status was 0. The treatment was well tolerated and toxicity was mild. Two patients had grade III hepatic toxicity; one had grade III hyperglycemia. There were no treatment-related deaths. No objective responses were demonstrated. In summary, toremifene is not effective therapy for AIPC at the dose and schedule evaluated in this trial.

Isolated profound thrombocytopenia associated with clopidogrel.

Clopidogrel is a new oral antiplatelet agent with a structure and mechanism of action similar to ticlopidine; they both block the adenosine diphosphate receptor. Because of better side-effect profile and simpler dosing regime, clopidogrel has largely replaced ticlopidine. In fact, the excellent safety and tolerability profile of clopidogrel compares favorably with that of aspirin as documented in the CAPRIE (Clopidogrel versus Aspirin in Patients at Risk of Ischemic Events) study. After marketing, several cases of clopidogrel-associated thrombotic thrombocytopenic purpura (TTP) were reported. We report our experience with a case of isolated profound thrombocytopenia without evidence of TTP after clopidogrel administration with prompt recovery of platelet counts upon discontinuation of clopidogrel and treatment with intravenous immunoglobulin.

At what cost? The social impact of American Indian gaming.

American Indian gaming has been called the "new buffalo." It has the potential to greatly influence cultural traditions on American Indian reservations. This study looks at the social impact that American Indian gaming is having on one reservation in northern Minnesota. Tribal members share strong feelings, both positive and negative, about the issue. Concerns about gaming include an increase in gambling abuse and addiction; a lack of appropriate child care; and concern that gaming is replacing traditional social activities. Some express concern that American Indian values are being replaced by materialism. Supporters of gaming point out that gaming provides tribal members with an opportunity to learn job skills and have gainful employment. Implications for social policy are given.

Nerve ingrowth into diseased intervertebral disc in chronic back pain.

BACKGROUND: In the healthy back only the outer third of the annulus fibrosus of the intervertebral disc is innervated. Nerve ingrowth deeper into diseased intervertebral disc has been reported, but how common this feature is and whether it is associated with chronic pain are unknown. We examined nerve growth into the intervertebral disc in the pathogenesis of chronic low back pain. METHODS: We collected 46 samples of intervertebral discs from 38 patients during spinal fusion for chronic back pain. 30 samples were from pain levels clinically established by discography and 16 samples were from adjacent vertebral levels with no pain. We obtained 34 control samples of intervertebral disc from previously healthy individuals with normal histology within 8 h of recorded death. We used standard immunohistochemical techniques to test for a general nerve marker, a nociceptive neurotransmitter (substance P), and a protein expressed during axonogenesis (growth-associated protein 43 [GAP43]). FINDINGS: We identified nerve fibres in the outer third of the annulus fibrosus in 48 (60%) of the 80 samples of intervertebral discs. Nerves were restricted to the outer or middle third of the annulus fibrosus in the 34 control samples. Among the patients with chronic low back pain, nerves extended into the inner third of the annulus fibrosus and into the nucleus pulposus in 21 (46%) and ten (22%) samples, respectively. Nerves usually accompanied blood vessels, but in 14 of the samples from back-pain patients, isolated nerve fibres were seen in the discal matrix. Both types of nerve fibres expressed substance P, but only non-vessel-associated fibres expressed GAP43. Deep nerve ingrowth into the inner third of the annulus fibrosus, the nucleus pulposus, or both was seen in four (25%) of 16 biopsy samples from non-pain levels and in 17 (57%) samples from pain levels. Of the 16 paired samples from both pain and non-pain levels, five pain-level samples and one non-pain-level sample showed deep nerve ingrowth. INTERPRETATION: Our finding of isolated nerve fibres that express substance P deep within diseased intervertebral discs and their association with pain suggests an important role for nerve growth into the intervertebral disc in the pathogenesis of chronic low back pain.

Method to derive ocean absorption coefficients from remote-sensing reflectance.

A method to derive in-water absorption coefficients from total remote-sensing reflectance (ratio of the upwelling radiance to the downwelling irradiance above the surface) analytically is presented. For measurements made in the Gulf of Mexico and Monterey Bay, with concentrations of chlorophyll-a ranging from 0.07 to 50 mg/m(3), comparisons are made for the total absorption coefficients derived with the suggested method and those derived with diffuse attenuation coefficients. For these coastal to open-ocean waters, including regions of upwelling and the Loop Current, the results are as follows: at 440 nm the difference between the two methods is 13.0% (r(2) = 0.96) for total absorption coefficients ranging from 0.02 to 2.0 m(-1); at 488 nm the difference is 14.5% (r(2) = 0.97); and at 550 nm the difference is 13.6% (r(2) = 0.96). The results indicate that the method presented works very well for retrieval of in-water absorption coefficients exclusively from remotely measured signals, and that this method has a wide range of potential applications in oceanic remote sensing.

Model for the interpretation of hyperspectral remote-sensing reflectance.

Remote-sensing reflectance is easier to interpret for the open ocean than for coastal regions because the optical signals are highly coupled to the phytoplankton (e.g., chlorophyll) concentrations. For estuarine or coastal waters, variable terrigenous colored dissolved organic matter (CDOM), suspended sediments, and bottom reflectance, all factors that do not covary with the pigment concentration, confound data interpretation. In this research, remote-sensing reflectance models are suggested for coastal waters, to which contributions that are due to bottom reflectance, CDOM fluorescence, and water Raman scattering are included. Through the use of two parameters to model the combination of the backscattering coefficient and the Q factor, excellent agreement was achieved between the measured and modeled remote-sensing reflectance for waters from the West Florida Shelf to the Mississippi River plume. These waters cover a range of chlorophyll of 0.2-40 mg/m(3) and gelbstoff absorption at 440 nm from 0.02-0.4 m(-1). Data with a spectral resolution of 10 nm or better, which is consistent with that provided by the airborne visible and infrared imaging spectrometer (AVIRIS) and spacecraft spectrometers, were used in the model evaluation.

Low-dose antacids and nonsteroidal anti-inflammatory drug-induced gastropathy in humans.

Gastroduodenal injury induced by nonsteroidal anti-inflammatory drugs (NSAIDs) is common. As yet, the ideal means to prevent NSAID-related mucosal injury remains controversial. Antacids are effective agents in treating gastric and duodenal ulcers unrelated to NSAIDs. The aim of this study was to assess the ability of a low-dose antacid to prevent NSAID injury in humans. Fifty healthy human volunteers were studied using a randomized, double-blind, placebo controlled, crossover design. After initial endoscopy, subjects were randomized to either Maalox TC (1 tablet q.i.d., acid neutralizing capacity of 104 mEq/day) or identical placebo while receiving 500 mg of naproxen b.i.d. for 21 days. After this period, a second endoscopy was performed to count antral and duodenal erosions and to evaluate symptoms and compliance with study medications. A 21-day washout period ensued, followed by a third endoscopy to insure a return to endoscopically normal mucosa. Subjects then crossed over into the alternate treatment arm for a further 21 days, followed by a fourth endoscopy to assess erosions. Forty subjects completed the study. Subjects receiving Maalox TC developed a significantly greater number of gastric erosions than did those on placebo. While this result was unforeseen, it is supported by statistical analysis and may have clinical relevance in regard to short-term NSAID therapy.

Establishment and characterization of a subclone (U-937-AG) from a permanent human monocyte cell line.

The human cell line U-937 has many features suggestive of the monocyte. It may be stimulated in vitro to develop attributes of an activated macrophage with increased phagocytosis and enhanced Fc receptor expression. We describe the establishment of a subclone designated U-937 AG through the use of a mutagenic agent. The features of this subclone include increased tumoricidal cytotoxicity, increased Fc receptor expression for IgG and enhanced phagocytosis of antibody coated erythrocytes, while retaining the usual light microscopic features. The mutant cell line is also capable of producing an erythroid potentiating factor while temporary production of a granulocyte macrophage colony stimulating factor was noted. The availability of a "resting" parent and a more "activated" subclone of this human monocyte cell line should assist in the study of human monocyte activation.

Lactate dehydrogenase in rabbit oocytes and eggs.

It has recently been reported that the rabbit oocyte lactate dehydrogenase (LDH) isozyme pattern shifts dramatically at ovulation. We have determined that both ovarian oocytes and ovulated eggs have predominantly LDH-5 with minor amounts of LDH-4. Therefore, no change occurs at ovulation. When oocytes or eggs are not treated to remove follicle cells, all five LDH isozymes are observed. Isolated follicle cells also have five isozymes. We suggest that failure to remove follicle cells can cause altered LDH isozyme patterns and may account for conflicting results in the literature.