Nano-manipulation of diamond-based single photon sources.

The ability to manipulate nano-particles at the nano-scale is critical for the development of active quantum systems. This paper presents a technique to manipulate diamond nano-crystals at the nano-scale using a scanning electron microscope, nano-manipulator and custom tapered optical fibre probes. The manipulation of a approximately 300 nm diamond crystal, containing a single nitrogen-vacancy centre, onto the endface of an optical fibre is demonstrated. The emission properties of the single photon source post manipulation are in excellent agreement with those observed on the original substrate.

Analysis of changes in optical fibers during arc-fusion splicing by use of quantitative phase imaging.

A non-interferometric imaging technique in conjunction with Abel inversion is used to directly and quantitatively examine the changes in optical fibers due to the heating produced during arc-fusion splicing as a function of fusion arc parameters. Phase images in the vicinity of a fusion splice are obtained using Quantitative Phase Microscopy, allowing the refractive-index change to be reconstructed with high spatial resolution. This simple, nondestructive method confirms that, for a fixed arc current, while the fusion time increases, the refractive-index of both fiber cores within the fusion region decreases in magnitude, the core region broadens, and the axial gradient decreases.

Refractive index profiling of axially symmetric optical fibers: a new technique.

We present a new technique for determining the refractive index profiles of axially symmetric optical fibers based on imaging phase gradients introduced into a transmitted optical field by a fiber sample. An image of the phase gradients within the field is obtained using a new non-interferometric technique based on bright field microscopy. This provides sufficient information to reconstruct the refractive index profile using the inverse Abel transform. The technique is robust, rapid and possesses high spatial resolution and we demonstrate its application to the reconstruction of the refractive index profiles of a single-mode and a multimode optical fiber.

Refractive-index profiling of optical fibers with axial symmetry by use of quantitative phase microscopy.

The application of quantitative phase microscopy to refractive-index profiling of optical fibers is demonstrated. Phase images of axially symmetric optical fibers immersed in index-matching fluid are obtained, and the inverse Abel transform is used to obtain the radial refractive-index profile. This technique is straightforward, nondestructive, repeatable, and accurate. Excellent agreement, to within approximately 0.0005, between this method and the index profile obtained with a commercial profiler is obtained.

Effect of a bioflavonoid dietary supplement on acetaminophen-induced oxidative injury to feline erythrocytes.

OBJECTIVE: To determine the effect of a commercial bioflavonoid antioxidant on acetaminophen-induced oxidative injury to feline erythrocytes. DESIGN: Randomized controlled study. ANIMALS: 45 healthy age-matched cats. PROCEDURE: Cats were assigned to 3 experimental groups. Groups 1 and 3 received a bioflavonoid antioxidant (10 mg/d) orally for 2 weeks. Groups 2 and 3 received an oxidative challenge with acetaminophen (90 mg/kg [41 mg/lb] of body weight, PO) on day 7. Packed cell volume, percentage of erythrocytes with Heinz bodies, blood methemoglobin concentration, and blood reduced and oxidized glutathione concentrations were determined at various times during the 2-week study period. RESULTS: Adverse effects were not associated with bioflavonoid antioxidant administration alone. Acetaminophen administration resulted in a significant increase in methemoglobin concentration in groups 2 and 3; differences were not detected between these groups. Heinz body concentrations in groups 2 and 3 increased after acetaminophen administration; however, the increase in cats that received the antioxidant was significantly less than in group-2 cats. Total blood glutathione concentrations did not change significantly in groups 2 and 3 after acetaminophen administration; however, ratio of reduced to oxidized glutathione concentration increased significantly after administration in group-2 cats, compared with group-3 cats. CONCLUSIONS AND CLINICAL RELEVANCE: Oral administration of bioflavonoid antioxidants to cats at risk for oxidative stress may have a beneficial effect on their ability to resist oxidative injury to erythrocytes.

Osteosynthesis of intra-articular fractures in the proximal interphalangeal joint with Kirschner wires.

Twenty-eight consecutive patients, aged 4-68 years, who had had an intra-articular fracture of the proximal interphalangeal (PIP) joint were reviewed retrospectively in 1996. All patients were operated on within a median of three days (range 0-26). Only three patients had open injuries while 11 had fracture-dislocations. A median of half the articular surfaces were involved, and dislocations ranged from 1-4 mm. Twelve patients had their fractures anatomically reduced and 13 had postoperative dislocations of less than 1 mm. Eighteen patients were reviewed after 10-49 months, and four were interviewed by telephone. The median reduction in range of movement in the PIP joint at follow-up was 15 degrees (range 0-90 degrees). Nine patients had subjectively slightly reduced movements, and only three of 17 patients stated that they had limited movement. Ten patients had occasional pain, which eight described as mild and two as moderate. Two patients had ulnar instability less than 5 degrees, and the remainder were stable. Twelve patients had a cold sensation in the affected finger joint in cold weather. No patients had changed occupation as a result of their injury, and only two patients said that they were limited in any way in any activity at work or at home. Open and precise reduction and osteosynthesis with Kirschner (K) wires seems to be an effective treatment for most intra-articular fractures of PIP joints.

Low-protein diet and kidney function in insulin-dependent diabetic patients with diabetic nephropathy.

BACKGROUND: Initiation of a low-protein diet (LPD) in patients with various nephropathies induces a faster initial and slower subsequent decline in the glomerular filtration rate (GFR). Whether this initial phenomenon is reversible or irreversible remains to be elucidated. METHODS: We performed an eight-week prospective, randomized, controlled study comparing the effect of an LPD with a normal-protein diet (NPD) in 29 insulin-dependent diabetic patients with diabetic nephropathy. At baseline, the patients were randomized to either an LPD (0.6 g.kg-1.24 hr-1, LPD group, N = 14) or their NPD (NPD group, N = 15) for four weeks (phase I). Between weeks 4 and 8, all patients received their NPD (phase II, recovery). Dietary protein intake (g.kg-1.24 hr-1), GFR (51Cr-EDTA, ml.min-1.1.73 m-2), albuminuria (enzyme-linked immunoadsorbent assay, mg.24 hr-1), and arterial blood pressure (Hawksley random zero sphygmomanometer, mm Hg) were measured at baseline and after four- and eight-weeks of follow-up. During the investigation, all patients in the LPD group (N = 12) and in the NPD group (N = 14) received their usual antihypertensive treatment. RESULTS: At baseline, the LPD group and the NPD group were comparable regarding dietary protein intake, GFR, albuminuria, and arterial blood pressure. During phase I, a significant decline in dietary protein intake, GFR, and albuminuria (mean, 95% CI) was observed in the LPD group [0.4 (0.3 to 0.5) g.kg-1.24 hr-1, 8.6 (3.2 to 13.9) ml.min-1.1.73 m-2, and 28.7 (14.0 to 40.9)%, respectively] compared with the NPD group [0.0 (-0.1 to 0.2) g.kg-1.24 hr-1 (P < 0.0001 between diets), 2.5 (-1.8 to 6.8) ml.min-1.1.73 m-2 (P = 0.07 between diets), and 0.0 (-20.1 to 23.5)% (P < 0.05 between diets), respectively]. Conversely, during phase II, a significant increase in dietary protein intake, GFR, and albuminuria [mean, 95% CI; 0.3 (0.2 to 0.5) g.kg-1.24 hr-1, 5.9 (0.8 to 11.1) ml.min-1.1.73 m-2, and 25.0 (4.5 to 49.6)%, respectively] took place in the LPD group compared with the NPD group [0.0 (-0.2 to 0.1) g.kg-1.24 hr-1 (P < 0.0001 between diets), -2.9 (-6.4 to 0.6) ml.min-1.1.73 m-2 (P < 0.01 between diets), and 2.9 (-18.3 to 29.7)% (P = 0.16 between diets), respectively]. Arterial blood pressure was comparable in the two groups of patients during phase I and II. CONCLUSIONS: Dietary protein restriction for four weeks induces a reversible decline in GFR and albuminuria in insulin-dependent diabetic patients with diabetic nephropathy, whereas systemic blood pressure remains unchanged.

Effects of 6alpha-methylprednisolone acetate on an equine osteochondral fragment exercise model.

OBJECTIVE: To determine effects of intra-articularly administered 6alpha-methylprednisolone acetate (MPA) in exercised horses with carpal osteochondral fragmentation. ANIMALS: 18 horses: 3 groups of 6 each. PROCEDURE: An osteochondral (chip) fragment was created in 1 randomly chosen middle carpal joint of each horse. Polyionic fluid (PF) was injected into both middle carpal joints of horses in the control group. In horses of the MPA-control group, MPA was injected into the middle carpal joint without an osteochondral fragment; a similar volume of PF was injected into the contralateral middle carpal joint. In the MPA-treated group of horses, 100 mg of MPA was injected into the middle carpal joint containing the osteochondral fragment; a similar volume of PF was injected into the contralateral joint. Injections were administered on postsurgical days 14 and 28, and horses were exercised on a high-speed treadmill for 8 weeks, starting on postsurgical day 15. RESULTS: Clinical improvement in degree of lameness was not associated with MPA administration. Joints that contained an osteochondral fragment and were treated with MPA had lower prostaglandin E2 concentration in synovial fluid, and lower scores for intimal hyperplasia and vascularity in synovial membrane, compared with PF-treated joints. However, articular cartilage erosion and morphologic lesions suggested possible deleterious effect of intra-articular MPA administration. CONCLUSIONS: Some beneficial effects of MPA administration on synovial fluid and synovial membrane were identified; however, the deleterious findings contrast with those associated with triamcinolone acetonide used in a similar model, but agree with other results of MPA administration in normal and abnormal joints.

Normal reference intervals and the effects of time and feeding on serum bile acid concentrations in llamas.

Fifty clinically healthy llamas, 0.5-13 years of age (22 intact males, 10 neutered males, 18 females), with no biochemical evidence of liver disease or hematologic abnormalities, were selected to establish serum bile acid reference intervals. Serum samples submitted to the clinical pathology laboratory were analyzed using a colorimetric enzymatic assay to establish bile acid reference intervals. A nonparametric distribution of llama bile acid concentrations was 1-23 micromol/liter for llamas >1 year of age and 10-44 micromol/liter for llamas < or = 1 year of age. A significant difference was found between these 2 age groups. No correlation was detected between gender and bile acid concentrations. The reference intervals were 1.1-22.9 micromol/liter for llamas >1 year of age and 1.8-49.8 micromol/liter for llamas < or = 1 year of age. Additionally, a separate group of 10 healthy adult llamas (5 males, 5 females, 5-11 years of age) without biochemical or hematologic abnormalities was selected to assess the effects of feeding and time intervals on serum bile acid concentrations. These 10 llamas were provided fresh water and hay ad libitum, and serum samples were obtained via an indwelling jugular catheter hourly for 11 hours. Llamas were then kept from food overnight (12 hours), and subsequent samples were taken prior to feeding (fasting baseline time, 23 hours after trial initiation) and postprandially at 0.5, 1, 2, 4, and 8 hours. In feeding trials, there was no consistent interaction between bile acid concentrations and time, feeding, or 12-hour fasting. Prior feeding or time of day did not result in serum bile acid concentrations outside the reference interval, but concentrations from individual llamas varied within this interval over time.

Intake of a diet high in trans monounsaturated fatty acids or saturated fatty acids. Effects on postprandial insulinemia and glycemia in obese patients with NIDDM.

OBJECTIVE: High intake of trans fatty acids and saturated fatty acids (SFAs) is known to increase the risk of coronary heart disease. We studied the effects of diets enriched in various fatty acids on postprandial insulinemia and fasting serum levels of lipids and lipoproteins in obese patients with NIDDM. RESEARCH DESIGN AND METHODS: Sixteen obese NIDDM patients were studied in a free-living outpatient regimen. After a run-in period, the patients received three different isocaloric diets for 6 weeks using a randomized crossover design. The patients were instructed to keep the energy intake from carbohydrate and protein constant at 50 and 20 E% (percent of energy intake), respectively, on all three diets. The fat composition of the diets differed: saturated fat (SAT) diet (20 E% SFAs, 5 E% polyunsaturated fatty acids [PUFAs], and 5 E% monounsaturated fatty acids [MUFAs]) versus cis monounsaturated fatty acid (CMUFA) diet (20 E% cis-MUFAs, 5 E% PUFAs, and 5 E% SFAs) versus trans monounsaturated fatty acid (TMUFA) diet (20 E% trans-MUFAs, 5 E% PUFAs, and 5 E% SFAs). Fasting serum levels of lipids and lipoproteins were measured at baseline and in the fasting state before meal tolerance tests at the end of each study period. Insulin secretion was assessed from incremental serum insulin and C-peptide responses during the meal tests. RESULTS: BMI, waist-to-hip ratio, and glycemic control remained stable throughout the study. After meal stimulation, postprandial glycemic responses were similar on all diets; however, serum insulin and C-peptide responses were greater following the TMUFA and SAT diets than following the baseline or CMUFA diets (P < 0.05). No statistical difference was found in fasting levels of serum lipids (total cholesterol, triglyceride, phospholipid, and nonesterified fatty acids) or lipoproteins of HDL cholesterol, VLDL cholesterol, LDL cholesterol, and apolipoprotein B between diets. CONCLUSIONS: In the presence of unchanged glycemia, both dietary trans fatty acids and SFAs induce an increase in postprandial insulinemia in obese patients with NIDDM.

Hematology and hemostasis in the horse: normal functions and common abnormalities.

In diseased animals, laboratory evaluations of erythrocytes, leukocytes, and hemostasis provide important information that contributes to either narrowing the list of potential diagnoses or to determining a specific diagnosis. To adequately interpret the results of these evaluations, normal erythrocyte and leukocyte kinetics and normal hemostatic function must be understood. In addition, knowledge of common diseases resulting in abnormalities of these laboratory tests and of typical changes in these tests caused by these diseases is vital. This article has reviewed normal erythrocyte and leukocyte kinetics and normal hemostatic functions that are clinically significant and has described the laboratory abnormalities expected in common diseases affecting these functions.

[Landfill gas]. / Lossepladsgas.

In a landfill mixture of gases, consisting principally of methane and carbon dioxide, may be produced by microbial degradation of organic waste under anaerobic conditions. Methane is explosive at concentrations between 5 and 15% by volume. Other gases, for instance hydrogensulphide, mercury and ethane, may be emitted at low concentrations, but usually do not represent a health hazard following normal atmospheric dilution. Indoor climate may be affected, though, in cases of accumulation in closed spaces. A case is presented where two persons died following an explosion caused by lighting a cigarette in their house which was surrounded on three sides by a landfill. The explosion occurred after heavy precipitation on a day with low atmospheric pressure. Methane measurements showed values consistent with risk of explosion.

Polycythemia in a llama.

The PCV of a llama increased from 50.8 to 74.0% during a 19-month period. The llama remained clinically normal unless stressed, when it would become dyspneic and tachypneic. Thoracic auscultation revealed sounds consistent with pneumonia, but were probably attributable to pulmonary congestion resulting from polycythemia. A diagnosis of secondary absolute polycythemia was made on the basis of high serum erythropoietin concentrations and no evidence of hypoxia. Necropsy revealed congestion of the lungs and liver. Cause of the polycythemia was not determined. Polycythemia should be considered as a differential diagnosis in a llama with exercise intolerance and harsh bronchovesicular sounds.

[99mTc anti-carcinoembryonic antigen in colorectal cancer]. / 99mTc-anti-karcinoembryonalt antigen ved kolorektal cancer.

This investigation is a part of a phase three multicentre immunoscintigraphy study of a technetium-99m labelled monoclonal antibody (Mab), BW 431/26, directed against carcino-embryonic antigen (CEA). Ten patients with recently colonoscopically verified primary colorectal cancer were evaluated. In nine of ten patients colorectal cancers were detected by wholebody immunoscintigraphy and by single photon emission computerized tomography (SPECT). The ten patients were operated upon, and in nine cases immunohistochemical investigations were performed. Immunohistochemical investigation of nine tumour specimens show that CEA was present in much higher concentrations in the tumour than in normal intestinal epithelium. Active accumulation of the labelled Mab in tumours was demonstrated by scintimetry. There is a demand for new diagnostic techniques for early diagnosis of colo-rectal cancer. Immunoscintigraphy must however compete with other diagnostic possibilities. The development of immunoscintigraphic technique is proceeding very rapidly, and there is probably a future for the use of immunological methods in diagnosis and therapy of cancer.

Evaluation of bone marrow cytology and stainable iron content in healthy adult llamas.

Complete blood counts and sternal bone marrow aspirates were obtained from healthy adult llamas ranging in age from 2.5 to 8.4 years. Megakaryocyte numbers and erythroid and myeloid series maturation and morphology appeared similar to other mammalian species. The particles contained 50 to 75% marrow cells with the remainder composed of lipocytes and stromal cells. In samples with numerous particles and adequate cellularity, M/E ratios ranged from 0.9 to 2.9. Samples with higher white blood cell counts and fewer particles had higher M/E ratios. Eosinophils comprised 14.3% of the myeloid series which is higher than other domestic mammals. Hemosiderin granules were numerous in marrow particles.

Tumor detection with 131I-labeled human monoclonal antibody COU-1 in patients with suspected colorectal carcinoma.

A major factor limiting the use of rodent monoclonal antibodies for diagnosis and therapy of cancer is the development of human anti-mouse immunoglobulin antibodies. Here we report a phase I/II immunodetection study of a human monoclonal antibody, COU-1, labeled with 131I. COU-1 is produced by a human-human hybridoma and recognizes a M(r) 43,000 cytokeratin-like protein strongly expressed by adenocarcinomas of the colon, breast, and ovary. Ten patients were given an i.v. infusion of 2 mg of antibody COU-1 labeled with 185 MBq of 131I. No adverse effects or toxicity were detected by conventional clinical tests nor by a complement activation assay for C3d. None of the patients developed antibodies against antibody COU-1 as determined by enzyme-linked immunosorbent assay and agglutination analysis. Tumor detection was successful in 7 of 9 cancer patients. The tenth patient proved to be a true negative. In several instances immunoscintigraphy gave additional or more correct information than conventional detection techniques. Tumors were most clearly outlined at days 5 and 7 after infusion. Primary colorectal carcinomas were detected by planar imaging in the cecum, ascending colon, and rectum with the smallest lesion measuring 3.0 cm in diameter. Immunoscintigraphy revealed multiple liver metastases in 1 of 3 patients. However, the livers of all 3 patients contained significantly more radioactivity (P < 0.005) than tumor-free livers of the other patients. Pharmacokinetics was evaluated in all patients. The clearance of 131I-labeled COU-1 from the circulation followed a triphasic pattern; an initial phase [t1/2 = 0.4 +/- 0.4 (SD) h] cleared 23% of the radioactivity followed by a rapid phase with a half-life of 13 +/- 3.8 h. The third phase (beta-phase) exhibited a half-life of 119 +/- 36 h, which is similar to the half-life reported for normal IgM. The human monoclonal antibody COU-1 directed against a predominantly intracellular cancer-associated antigen does not produce toxicity or induce antibody formation and seems to be a promising agent for detecting tumors with immunoscintigraphy.

Variability of alpha-tocopherol values associated with procurement, storage, and freezing of equine serum and plasma samples.

Recent evidence concerning the pathogenesis of equine degenerative myeloencephalopathy indicated that low blood alpha-tocopherol values are a factor in the disease process. Variables that could be introduced by a veterinarian procuring, transporting, or storing samples were evaluated for effects on alpha-tocopherol concentration in equine blood. These variables included temperature; light; exposure to the rubber stopper of the evacuated blood collection tube; hemolysis; duration of freezing time, with and without nitrogen blanketing; and repeated freeze/thaw cycles. It was found that hemolysis caused the greatest change in high-performance liquid chromatography-measured serum alpha-tocopherol values, with mean decrease of 33% (P < 0.001). Lesser, but significant (P < 0.01) changes in serum alpha-tocopherol values were an approximate 10% decrease when refrigerated blood was left in contact with the red rubber stopper of the blood collection tube for 72 hours and an approximate 5% increase when blood was stored at 20 to 25 C (room temperature) for 72 hours. Repeated freeze/thaw cycles resulted in a significant (P < 0.05) 3% decrease in alpha-tocopherol values in heparinized plasma by the third thawing cycle. Freezer storage for a 3-month period without nitrogen blanketing resulted in slight (2%) decrease in mean serum alpha-tocopherol values, whereas values in serum stored for an identical period under nitrogen blanketing did not change. A significant (P < 0.001) mean decrease (10.3%) in alpha-tocopherol values was associated with freezer (-16 C) storage of nitrogen blanketed serum for 6 months.(ABSTRACT TRUNCATED AT 250 WORDS)

Serially determined plasma alpha-tocopherol concentrations and results of the oral vitamin E absorption test in clinically normal horses and in horses with degenerative myeloencephalopathy.

Plasma alpha-tocopherol (vitamin E) values were monitored serially in 9 foals sired by a stallion with equine degenerative myeloencephalopathy (EDM) and in 5 age-matched control foals (sired by a clinically normal stallion) raised in the same environment for the first year of life. Clinical evaluation determined that 8 of the 9 foals sired by the stallion with EDM had neurologic deficits consistent with the disease on one or more occasions during the study period, whereas control foals had normal gait. From 6 weeks to 10 months of age, plasma alpha-tocopherol values in foals with signs of EDM were significantly (P less than 0.001) lower than those in control foals. An oral vitamin E absorption test was performed, and results for 8 of the affected horses and the affected stallion were compared with results for 4 of the monitored control horses and 4 additional control horses. Significant differences were not evident in any of the absorption indices. On the basis of data from this study and supported by reported prophylactic and therapeutic benefits of supplemented vitamin E, low plasma concentration of vitamin E is concluded to be a factor in the development of EDM in the first year of life of hereditarily predisposed foals. It was also concluded that the significantly lower alpha-tocopherol values seen in the foals in this study did not reflect a primary gastrointestinal tract absorption problem.

Evaluation of the oral vitamin E absorption test in horses.

An oral vitamin E absorption test used in human beings was modified for use in horses. The most appropriate techniques with which to measure gastrointestinal tract absorption of vitamin E (alpha-tocopherol) in horses were developed. Vitamin E was administered orally, and serum values of alpha-tocopherol were measured by use of high-performance liquid chromatography at 0, 3, 6, 9, 12, and 24 hours after vitamin E administration. Variables included comparison of 2 dosages (45 and 90 IU/kg of body weight), routes of administration, and absorption dynamics of 3 preparations of dl-alpha-tocopherol. Absorption of the 2 doses of dl-alpha-tocopherol acetate indicated a dose response; the area under the curve at 24 hours (AUC24) was 4.3 micrograms.h/ml for the 45-IU/kg dose and 32.2 micrograms.h/ml (P less than 0.01) for the 90-IU/kg dose. Maximal absorption was apparent when vitamin E was naturally consumed in grain, compared with administration of identical preparations by stomach tube or paste. In the same horses, dl-alpha-tocopherol and dl-alpha-tocopherol acetate plus polyethylene glycol had statistically similar absorption curves and both had significantly greater AUC24, compared with dl-alpha-tocopherol acetate; values for the 3 compounds were 23.6, 25.8, and 12.6 micrograms.h/ml, respectively. The AUC24 varied between individual horses, but time of peak value was consistently observed between 6 and 9 hours.(ABSTRACT TRUNCATED AT 250 WORDS)