Visible laser emission from a praseodymium-doped fluorozirconate guided-wave chip.

We report visible continuous-wave laser emission at 636 nm from a praseodymium-doped fluorozirconate glass guided-wave chip laser. This ultra-fast laser inscribed gain chip is demonstrated to be a compact and integrated laser module. The laser module, pumped by 442 nm GaN laser diodes, generates >8 mW lasing output with a beam quality of Mxy2∼1.15×1.1(±0.1). To the best of our knowledge, this is the first visible laser emission from a glass-based waveguide chip laser.

A phase I/II trial of AT9283, a selective inhibitor of aurora kinase in children with relapsed or refractory acute leukemia: challenges to run early phase clinical trials for children with leukemia.

Aurora kinases regulate mitosis and are commonly overexpressed in leukemia. This phase I/IIa study of AT9283, a multikinase inhibitor, was designed to identify maximal tolerated doses, safety, pharmacokinetics, and pharmacodynamic activity in children with relapsed/refractory acute leukemia. The trial suffered from poor recruitment and terminated early, therefore failing to identify its primary endpoints. AT9283 caused tolerable toxicity, but failed to show clinical responses. Future trials should be based on robust preclinical data that provide an indication of which patients may benefit from the experimental agent, and recruitment should be improved through international collaborations and early combination with established treatment strategies.

Holmium-doped 2.1 µm waveguide chip laser with an output power > 1 W.

We demonstrate the increasing applicability of compact ultra-fast laser inscribed glass guided-wave lasers and report the highest-power glass waveguide laser with over 1.1 W of output power in monolithic operation in the short-infrared near 2070 nm achieved (51% incident slope efficiency). The holmium doped ZBLAN chip laser is in-band pumped by a 1945 nm thulium fiber laser. When operated in an extended-cavity configuration, over 1 W of output power is realized in a linearly polarized beam. Broad and continuous tunability of the extended-cavity laser is demonstrated from 2004 nm to 2099 nm. Considering its excellent beam quality of M² = 1.08, this laser shows potential as a flexible master oscillator for single frequency and mode-locking applications.

Widely tunable short-infrared thulium and holmium doped fluorozirconate waveguide chip lasers.

We report widely tunable (≈ 260 nm) Tm(3+) and Ho(3+) doped fluorozirconate (ZBLAN) glass waveguide extended cavity lasers with close to diffraction limited beam quality (M(2) ≈ 1.3). The waveguides are based on ultrafast laser inscribed depressed claddings. A Ti:sapphire laser pumped Tm(3+)-doped chip laser continuously tunes from 1725 nm to 1975 nm, and a Tm(3+)-sensitized Tm(3+):Ho(3+) chip laser displays tuning across both ions evidenced by a red enhanced tuning range of 1810 to 2053 nm. We also demonstrate a compact 790 nm diode laser pumped Tm(3+)-doped chip laser which tunes from 1750 nm to 1998 nm at a 14% incident slope efficiency, and a beam quality of M(2) ≈ 1.2 for a large mode-area waveguide with 70 µm core diameter.

Superior sensitivity and decreased time to detection with the Bactec Peds Plus/F system compared to the BacT/Alert Pediatric FAN blood culture system.

Here, we compare the sensitivities and times to detection (TTD) of BacT/Alert Pediatric FAN (PF) and Bactec Peds Plus blood culture bottles. Test bottles were inoculated with 2 ml of banked whole blood, 1-ml aliquots of antibiotic suspension, and organisms diluted to simulate a bacteremia level of 10 to 100 CFU/ml. The control bottles were inoculated with 3 ml of banked blood and organism suspensions only. The organism-drug combinations were Staphylococcus epidermidis and vancomycin, methicillin-resistant Staphylococcus aureus and vancomycin, Streptococcus pneumoniae, vancomycin, and ceftriaxone, Streptococcus agalactiae, ampicillin, and cefotaxime, Escherichia coli, cefotaxime, and cefepime, Pseudomonas aeruginosa, piperacillin-tazobactam, cefepime, and gentamicin, Neisseria meningitidis and ceftriaxone, and Haemophilus influenzae and ceftriaxone. The control and test bottle combinations were tested in duplicate. The bottles were incubated for 5 days; 32 control and 104 test bottles were incubated. Overall, the bacterial recovery rates for the PF and Peds Plus bottles were 37% and 62%, 94% and 100% in the controls, 19% and 50% in the test bottles, and 33% and 92% in the bottles with vancomycin, respectively. No bacteria were recovered from the bottles with S. pneumoniae, S. agalactiae, E. coli, N. meningitidis, or H. influenzae in combination with cefotaxime or ceftriaxone. The Peds Plus system detected P. aeruginosa in bottles with cefepime and piperacillin-tazobactam, but the PF system recovered bacteria only in bottles with trough levels of piperacillin-tazobactam. The mean TTD were shorter in the Peds Plus system controls (14.2 versus 18.0 h; P = 0.001) and the test bottles (14.3 versus 17.8 h; P = 0.008) than in the PF bottles. Overall, we demonstrated superior sensitivity, TTD, and antibiotic neutralization in the Bactec Peds Plus system compared to those in the Pediatric FAN system.

Local Anaesthesia for Enzymatic Debridement of Cutaneous Burns: A Prospective Analysis of 27 Cases.

Enzymatic debridement (ED) is increasingly used for cutaneous burns. Compared with surgical debridement, ED has better preservation of viable dermis, less blood loss and autografting, however ED is painful. Current recommendations suggest local anaesthesia (LA) is useful for minor burns, but the evidence base is minimal. In our centre, we routinely use LA with good analgesic effect. This study was a single-centre, prospective analysis conducted at the Queen Victoria Hospital (UK). Patients had at least superficial partial thickness burns and received subcutaneous LA prior to ED during a 1-year period (October 2019-September 2020). Pain was assessed using a numeric scale of 1-10, recorded before, during and after the procedure. In total, 27 patients were included (n=17 males) with a median age of 47 (18-88 years). The mean total burn surface area was 1.5% (0.3-5.0). Treated sites included head and neck (1), trunk (5), upper limb (9) and lower limb (16). The most used LAwas bupivacaine 0.25% (n=25), followed by lidocaine 1% (n=2). Some required additional oral analgesia (n=8) or a regional blockade (n=2). Average pain score during debridement was 1.9 We have found LA effective, with favourable pain scores in comparison to previous studies with oral analgesia or regional blockade. LA is quick and easy to perform, as opposed to nerve blocks, which require trained personnel with ultrasound guidance. LA is a useful analgesic for patients with minor cutaneous burns undergoing ED. In some cases, it is sufficient without additional oral analgesia or regional blockade.

Le débridement enzymatique (DE) des brûlures est de plus en plus utilisé, ayant l'avantage d'être moins hémorragique et plus respectueux des tissus sains que la chirurgie, au prix d'une douleur plus importante. Les recommandations actuelles suggèrent l'utilisation de l'anesthésie locale (AL) sur les petites zones, avec un niveau de preuve minime. Dans notre centre, nous utilisons régulièrement l'AL, avec un bon effet analgésique. Cette étude a été conduite dans le CTB de l'hôpital Queen Vicoria (Royaume Uni). Durant 1 année (octobre 2019- septembre 2020), les patients devant bénéficier d'un DE recevaient préalablement une AL par infiltration. La douleur a été évaluée par échelle numérique (0 à 10) avant, pendant et après la procédure. Nous avons étudié 27 patients dont 17 hommes, d'âge médian 47 ans (18 à 88), brûlés en moyenne sur 1,5% (0,3 à 5), sur le cou (1), le tronc (5), le membre supérieur (9) et le membre supérieur (16). La bupivacaïne 0,25% a été la plus utilisée (25 fois), la lidocaïne 1% l'étant anecdotiquement (2 fois). Une analgésie complémentaire a été 10 fois nécessaire : orale 8 fois, régionale 2 fois. La douleur procédurale était cotée à 1,9 en moyenne. Nous estimons que l'AL est efficace, avec des scores de douleur favorables comparativement aux analgésies orale ou régionale. À la différence des analgésies régionales qui nécessitent un personnel entraîné et un écho- guidage, l'AL est facile et rapide. Elle peut être suffisante à elle seule pour le DE de brûlures minimes.

Versatile large-mode-area femtosecond laser-written Tm:ZBLAN glass chip lasers.

We report performance characteristics of a thulium doped ZBLAN waveguide laser that supports the largest fundamental modes reported in a rare-earth doped planar waveguide laser (to the best of our knowledge). The high mode quality of waveguides up to 45 um diameter (~1075 µm(2) mode-field area) is validated by a measured beam quality of M(2)~1.1 ± 0.1. Benefits of these large mode-areas are demonstrated by achieving 1.9 kW peak-power output Q-switched pulses. The 1.89 µm free-running cw laser produces 205 mW and achieves a 67% internal slope efficiency corresponding to a quantum efficiency of 161%. The 9 mm long planar chip developed for concept demonstration is rapidly fabricated by single-step optical processing, contains 15 depressed-cladding waveguides, and can operate in semi-monolithic or external cavity laser configurations.

2.1 µm waveguide laser fabricated by femtosecond laser direct-writing in Ho3+, Tm3+:ZBLAN glass.

We report the first Ho3+ doped waveguide laser, which was realized by femtosecond direct-writing of a depressed cladding structure into ZBLAN glass. Tm3+ sensitizing allows the 9 mm long Ho3+ gain medium to be conveniently pumped at 790 nm, achieving an optical-to-optical slope efficiency of 20% and a threshold of 20 mW. The potentially widely tunable laser produces up to 76 mW at 2052 nm and also operates at shorter wavelengths near 1880 nm and 1978 nm for certain cavity configurations.

Fifty percent internal slope efficiency femtosecond direct-written Tm³âº:ZBLAN waveguide laser.

We report a 790 nm pumped, Tm³âº doped ZBLAN glass buried waveguide laser that produces 47 mW at 1880 nm, with a 50% internal slope efficiency and an M² of 1.7. The waveguide cladding is defined by two overlapping rings created by femtosecond direct-writing of the glass, which results in the formation of a tubular depressed-index-cladding structure, and the laser resonator is defined by external dielectric mirrors. This is, to the best of our knowledge, the most efficient laser created in a glass host via femtosecond waveguide writing.

Modulation of gamma oscillations by endogenous adenosine through A1 and A2A receptors in the mouse hippocampus.

Adenosine serves as a homeostatic factor, regulating hippocampal activity through A(1) receptor-mediated inhibition. Gamma frequency oscillations, associated with cognitive functions, emerge from increased network activity. Here we test the hypothesis that hippocampal gamma oscillations are modulated by ambient adenosine levels. In mouse hippocampal slices exogenous adenosine suppressed the power of both kainate-induced gamma oscillations and spontaneous gamma oscillations, observed in a subset of slices in normal aCSF. Kainate-induced gamma oscillation power was suppressed by the A(1) receptor agonist PIA and potentiated by the A(1) receptor antagonist 8-CPT to three times matched control values with an EC(50) of 1.1microM. 8-CPT also potentiated spontaneous gamma oscillation power to five times control values. The A(2A) receptor agonist CGS21680 potentiated kainate-induced gamma power to two times control values (EC(50) 0.3nM), but this effect was halved in the presence of 8-CPT. The A(2A) receptor antagonist ZM241385 suppressed kainate-induced gamma power. The non-selective adenosine receptor antagonist caffeine induced gamma oscillations in slices in control aCSF and potentiated both kainate-induced gamma and spontaneous gamma oscillations to three times control values (EC(50) 28muM). Decreasing endogenous adenosine levels with adenosine deaminase increased gamma oscillations. Increasing endogenous adenosine levels with the adenosine kinase inhibitor 5-iodotubericidin suppressed gamma oscillations. Partial hypoxia-induced suppression of gamma oscillations could be prevented by 8-CPT. These observations indicate that gamma oscillation strength is powerfully modulated by ambient levels of adenosine through A(1) receptors, opposed by A(2A) receptors. Increased gamma oscillation strength is likely to contribute to the beneficial cognitive effects of caffeine.

Antiretroviral effect and safety of abacavir alone and in combination with zidovudine in HIV-infected adults. Abacavir Phase 2 Clinical Team.

OBJECTIVES: To evaluate, over 12 weeks, the antiretroviral activity and safety of abacavir, used alone and in combination with zidovudine (ZDV), as treatment for HIV-1-infected subjects who had limited or no antiretroviral treatment. DESIGN: Seventy-nine HIV-1-infected subjects, with CD4 cell counts 200-500 x 10(6)/l and <12 weeks of previous treatment with ZDV were enrolled in a multicenter study. Subjects were randomly assigned to one of four cohorts receiving abacavir monotherapy for the first 4 weeks (200, 400, or 600 mg every 8 h daily, or 300 mg every 12 h daily) and, thereafter, combination therapy of abacavir with 600 mg ZDV or ZDV placebo, administered in a double-blind manner for an additional 8 weeks. METHODS: Antiretroviral activity was assessed by measuring changes in plasma HIV-1 RNA levels and CD4+ cell counts. Safety was assessed by monitoring clinical adverse events and laboratory abnormalities during the 12-week period and for 4 weeks post-treatment. RESULTS: Treatment with abacavir, alone or in combination with ZDV, produced marked decreases in plasma HIV-1 RNA loads and increases in CD4+ cell counts in all groups. At week 4, median plasma HIV-1 RNA loads decreased by 1.11-1.77 log10 copies/ml and median CD4+ cell counts increased by 63-111 x 10(6)/l in all groups. At week 12, median HIV-1 RNA loads decreased by 1.02-2.24 log10 copies/ml (abacavir monotherapy) and by 1.81-2.01 log10 copies/ml (abacavir-ZDV); median CD4+ cell counts increased by 79-195 x 10(6)/l (abacavir monotherapy) and by 93-142 x 10(6)/l (abacavir-ZDV). At week 12, the percentage of subjects who had plasma HIV-1 RNA levels below 400 and 40 copies/ml were 28 and 11%, respectively (abacavir monotherapy) and 69 and 22%, respectively (abacavir-ZDV). Eight subjects (10%) discontinued the study prematurely because of adverse events; nausea (n = 4) and hypersensitivity (n = 3) were the most common reasons for withdrawal. There were no deaths among the study subjects. CONCLUSIONS: In HIV-infected subjects who have received little or no prior antiretroviral therapy, treatment with abacavir alone or in combination with ZDV is well tolerated and resulted in sustained improvements in key immunologic and virologic efficacy parameters through 12 weeks.

Prevention of relapse of histoplasmosis with fluconazole in patients with the acquired immunodeficiency syndrome.

OBJECTIVE: To assess the effectiveness of fluconazole for suppression of relapse of histoplasmosis in patients with acquired immunodeficiency syndrome (AIDS). DESIGN: Retrospective, nonrandomized, open trial. SETTING: Multicenter at two university referral centers and in five private practices. PATIENTS: Seventy-six patients with AIDS and disseminated histoplasmosis who completed induction treatment with amphotericin B, itraconazole, or fluconazole and maintained on treatment with fluconazole to prevent relapse. INTERVENTIONS: Fluconazole was given at dosages of 100 to 400 mg per day. Patients were followed by their primary physicians, who completed questionnaires collecting information about treatment and relapse status. Blood and urine specimens were submitted periodically for Histoplasma capsulatum var. capsulatum antigen determination. MEASUREMENTS AND MAIN RESULTS: Nine of the 76 patients relapsed during fluconazole therapy and another was removed from the study because of allergic rash. Survival after initiation of therapy for histoplasmosis was 94 weeks, ranging from 74 weeks for those who received less than 1 g of amphotericin B for induction and none for maintenance therapy to 156 weeks for those who received greater than 1 g for induction and additional amphotericin B for maintenance therapy before beginning fluconazole (P < 0.02). Antigen levels fell at rates of 0.05 units/week in urine and 0.02 units/week in serum in patients who were successfully maintained in remission and increased by > or = 2 units/week in 4 of 6 patients who relapsed. CONCLUSIONS: Fluconazole > or = 200 mg daily is a reasonable choice for chronic suppressive therapy of histoplasmosis in patients who cannot take itraconazole because of drug interactions, malabsorption, or side effects.

Glucose-insulin-potassium solutions enhance recovery after urgent coronary artery bypass grafting.

OBJECTIVE: This prospective, randomized, clinical study was undertaken to determine whether glucose-insulin-potassium solutions would benefit patients undergoing coronary artery bypass grafting because of unstable angina. METHODS: The study group consisted of 30 patients with unstable angina who required coronary artery bypass grafting. In 15 patients, glucose-insulin-potassium solution (30% dextrose in water; K+, 80 mEq/L: regular insulin, 50 units) was given intravenously at 1 ml/kg per hour after induction of anesthesia and administration continued for 12 hours after aortic unclamping. Fifteen patients in a separate group received 5% dextrose in water intravenously at 50 ml/hr. RESULTS: Patients treated with glucose-insulin-potassium solution had higher cardiac indices (2.8 +/- 0.1 vs 2.0 +/- 1 L/min per square meter; p < 0.001), lower inotrope scores (0.06 +/- 0.01 vs 0.46 +/- 0.19; p = 0.041), and less weight gain (6.4 +/- 9 vs 11.6 +/- 1.1 pounds; p < 0.001) and had shorter times of ventilator support (8.3 +/- 0.6 vs 14.2 +/- 0.2 hours; p = 0.003). They had a significantly lower incidence of atrial fibrillation (13.3% vs 53.3%; p = 0.020) and had shorter stays in the intensive care unit (14.8 +/- 1.3 vs 31.6 +/- 5.2 hours; p = 0.002) and in the hospital (6.0 +/- 0.4 vs 8.0 +/- 0.7 days; p = 0.010). CONCLUSIONS: We conclude that glucose insulin-potassium therapy enhances myocardial performance and results in faster recovery from urgent coronary artery bypass grafting.

Immunogenicity of the intradermal route of hepatitis B vaccination with the use of recombinant hepatitis B vaccine.

In March 1987, 32 hospital employees were enrolled in a prospective trial of intradermal recombinant hepatitis B vaccination. Enrollees were given 0.1 ml of vaccine on days 1, 30, and 180. Two weeks after the third intradermal vaccination, 81%, or 26, of the enrollees showed seropositivity (greater than or equal to 10 mIU antibody/ml) for hepatitis B surface antibody. Five of six nonresponders were given a fourth intradermal vaccination. Two additional seroconversions occurred, resulting in an overall conversion rate of 90% for recipients of up to four intradermal vaccine doses. Complications of vaccination were limited primarily to the occasional persistence (less than 6 months) of hyperpigmentation at the injection site. Administration of recombinant hepatitis B vaccine by the intradermal route proved to be a safe and effective method of vaccination. Cost savings of preexposure immunization with the intradermal versus the intramuscular route of vaccination were approximately $90 per enrollee. Efficacy and safety can be maximized by employing a fourth vaccine dose and routinely documenting seroconversion after vaccination.

Favorable impact of stents after emergent coronary artery bypass for failed angioplasty.

BACKGROUND: This study was undertaken to determine the impact of the use and availability of coronary stents on outcomes in patients requiring emergent coronary artery bypass graft (CABG) surgery following a failed percutaneous transluminal coronary angioplasty (PTCA). METHODS: Patients were divided into two groups based on the year of their CABG for a failed PTCA and the availability of stents: group 1, 1992 to 1994, stents not available (n = 34); and group 2, 1995 to 1997, stents available (n = 26). RESULTS: CABG patients in the group where stents were not available were more likely to have had an abrupt coronary occlusion (26 of 34 versus 3 of 26; p < 0.0001) and less likely to have had a dissection (8 of 34 versus 23 of 26; p < 0.0001) as their indication for emergent CABG. Patients in the stent era had a lower incidence of perioperative myocardial infarction (5 of 26 versus 17 of 34; p < 0.01) and a decreased mortality rate (0 of 26 versus 6 of 34; p < 0.03). In the 9 patients where stents were employed, patency of the lumen was restored in 8 patients and there was only 1 myocardial infarction. CONCLUSIONS: Stents have had a favorable impact on patients requiring an emergent CABG following a failed PTCA.

Factors influencing mortality after emergency coronary artery bypass grafting for failed percutaneous transluminal coronary angioplasty.

BACKGROUND: Emergency coronary artery bypass grafting after failed percutaneous transluminal coronary angioplasty is associated with increased mortality. METHODS: From 1981 through 1995, 117 patients at our institution underwent emergency coronary artery bypass grafting after failed percutaneous transluminal coronary angioplasty, with an in-hospital mortality rate of 13.6%. Univariate and multivariate analyses were used to identify the factors that influenced the risk of death. RESULTS: Univariate analysis revealed that patients who died more often were women and had chronic renal failure, lower ejection fractions, and more diffuse coronary artery disease; less often received an internal mammary artery graft or an antegrade perfusion catheter; required inotropic support in the cardiac catheterization laboratory; and experienced myocardial infarction. Multivariate analysis demonstrated that the need for inotropic support in the cardiac catheterization laboratory was the best predictor of perioperative death. CONCLUSIONS: Patients with a reduced ejection fraction in whom percutaneous transluminal coronary angioplasty fails, antegrade perfusion does not produce a response, and myocardial infarction occurs are more likely to die after coronary artery bypass grafting. The risk appears to be highest for patients who require inotropic support in the cardiac catheterization laboratory.

Leucocyte versus erythrocyte thioguanine nucleotide concentrations in children taking thiopurines for acute lymphoblastic leukaemia.

PURPOSE: The aim of this study was to compare leucocyte and erythrocyte thioguanine nucleotide (TGN) cytotoxic metabolite concentrations in children with lymphoblastic leukaemia taking mercaptopurine (MP) or thioguanine (TG) as part of their long-term remission maintenance chemotherapy. METHODS: Ten consecutive children treated on the MRC ALL97 protocol were studied. Six were randomized to TG and four to MP. Leucocyte and erythrocyte thiopurine nucleotide metabolites were measured after the children had been titrated to the standard thiopurine protocol dose, or higher. RESULTS: Children taking TG accumulated significantly higher erythrocyte TGN concentrations than those taking MP (median difference 1171 pmol/8 x 10(8) erythrocytes, 95% CI 766 to 2169, P<0.02), but there was no significant difference in the concentration range of leucocyte TGNs generated from TG or MP. In those children taking TG, median TGN concentrations were 5142 pmol/8 x 10(8) leucocytes and 1472 pmol/8 x 10(8) erythrocytes (3.5-fold difference, median difference 3390 pmol/8 x 10(8) cells, 95% CI 1559 to 7695, P=0.005), compared to 5422 pmol/8 x 10(8) leucocytes and 261 pmol/8 x 10(8) erythrocytes (20-fold difference, median difference 5054 pmol/8 x 10(8) cells, 95% CI 2281 to 6328, P=0.03) in those taking MP. CONCLUSIONS: Despite the accumulation of significantly higher erythrocyte TGN concentrations for TG compared with MP, the accumulation of leucocyte TGNs in children taking TG was similar to the range of leucocyte TGNs in children taking MP. Therefore, when correlating intracellular TGNs to clinical effect, the range of erythrocyte TGN metabolites will be higher for those children taking TG than in those taking MP.

Field intercomparison of a novel optical sensor for formaldehyde quantification.

A one-week in situ intercomparison campaign was completed on the Rice University campus for measuring HCHO using three different techniques, including a novel optical sensor based on difference frequency generation (DFG) operating at room temperature. Two chemical derivatization methods, 2,4-dinitrophenylhydrazine (DNPH) and o-(2,3,4,5,6-pentafluorobenzyl) hydroxylamine (PFBHA), were deployed during the daylight hours for three- to four-hour time-integrated samples. A real-time optical sensor based on laser absorption spectroscopy was operated simultaneously, including nighttime hours. This tunable spectroscopic source based on difference frequency mixing of two fiber-amplified diode lasers in periodically poled LiNb03 (PPLN) was operated at 3.5315 micrometers (2831.64 cm 1) to access a strong HCHO ro-vibrational transition free of interferences from other species. The results showed a bias of -1.7 and -1.2 ppbv and a gross error of 2.6 and 1.5 ppbv for DNPH and PFBHA measurements, respectively, compared with DFG measurements. These results validate the DFG sensor for time-resolved measurements of HCHO in urban areas.

Portable fiber-coupled diode-laser-based sensor for multiple trace gas detection.

Tunable narrowband mid-infrared radiation from 3.25 to 4.4 micrometers is generated by a compact fiber-coupled, difference-frequency-based spectroscopic source. A 20-mW external cavity diode laser (with a tuning range from 814 to 870 nm) and a 50-mW distributed-Bragg-reflector diode-laser-seeded ytterbium-doped fiber amplifier operating at 1083 nm are difference-frequency mixed in a multi-grating, temperature-controlled periodically poled LiNbO3 crystal. A conversion efficiency of 0.44 mW/(W2cm) (corresponding to a power of approximately equal to 3 microW at 3.3 micrometers) represents the highest conversion efficiency reported for a portable device. Performance characteristics of such a sensor and its application to spectroscopic detection of CO2, N2O, H2CO, HCl, NO2, and CH4 will be reported in this work.

Bacteremia in young urban women admitted with pyelonephritis.

The objective of this study was to determine the rate of bacteremia in young women admitted to the hospital with presumed pyelonephritis and compare it with other published rates. The study design was a retrospective, structured chart review and a review of published reports of bacteremic pyelonephritis. An urban county teaching hospital provided the setting for the study. The patients were nonpregnant women (n = 98) 44 years of age or younger who were without bladder dysfunction and who had not been admitted to an intensive care unit. Further criteria for participation included discharge with the diagnosis of acute pyelonephritis. Blood cultures were ordered for 69 women; the results of 64 were noted in the chart. Twenty-three women (35.9% of those cultured; 23.4% of all patients) were diagnosed with bacteremia. In patients for whom blood culture results were obtained, trends developed between those patients with bacteremia and those with complicated pyelonephritis, defined as a known or newly discovered genitourinary abnormality or a risk factor (P = 0.044), those who were black (P = .044), those with higher pulses on admission (P = .050), those with more white blood cells per high-powered field after urinalysis (P = 0.007), and those whose fever lasted longer (P = 0.033). Blood culture results were positive in two patients whose urine cultures were negative. This comparatively high bacteremia rate supports routine ordering of blood cultures for urban women suspected of having pyelonephritis.