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Nitric oxide radicals in leucocytes and vaginal washes of Trichomonas vaginalis -infected symptomatic and asymptomatic women

The clinical spectrum of Trichomonas vaginalis infection varies from asymptomatic to mild, moderate or severe vaginitis. Nitric oxide and other reactive nitrogen radicals produced by immune effector cells are important cytotoxic and cytostatic mediators against several microorganisms including parasites. In the present study, inducible nitric oxide synthase (iNOS) and reactive nitrogen intermediat

Radiatively driven convection in ice-covered lakes: Observations, scaling, and a mixed layer model

Penetrative convection is discussed where the instability is driven by radiative heating of water below the temperature of maximum density. Convection of this type occurs in ice-covered freshwater lakes in late spring, when the snow cover vanishes and solar radiation is absorbed beneath the ice cover. The vertical temperature structure, bulk mixed layer scaling, and mixed layer deepening are exami

Transcriptional dynamics of the embryonic stem cell switch

Recent ChIP experiments of human and mouse embryonic stem cells have elucidated the architecture of the transcriptional regulatory circuitry responsible for cell determination, which involves the transcription factors OCT4, SOX2, and NANOG. In addition to regulating each other through feedback loops, these genes also regulate downstream target genes involved in the maintenance and differentiation

CYP gene polymorphisms and early menarche

Early age at menarche is a risk factor for breast cancer. A previous study reported a significant positive association between the CYP3A4*1B variant allele and early puberty. We investigated whether polymorphisms of the CYP3A4, CYP17, CYP1B1, and CYP1A2 genes predict the age at onset of menarche. Five hundred eighty-three nulliparous women between ages 17 and 35, of various ethnic backgrounds, com

Tyrosinase-mediated formation of a reactive quinone from the depigmenting agents, 4-tert-butylphenol and 4-tert-butylcatechol

Exposure of the skin to certain phenols or catechols such as 4-tert-butylphenol (TBP) and 4-tert-butylcatechol (TBC) may cause leukoderma. These substances are used in the polymer industry and numerous cases have been reported. Several theories of the mechanism for chemical leukoderma have been suggested. In the present study, TBP and TBC are shown to be oxidised by tyrosinase. The oxidation of TB

Rat sciatic nerve regeneration through a micromachined silicon chip

The capacity of regenerating nerve fibres to grow through a perforated silicon chip was tested using the silicone chamber model for nerve regeneration. The chips were fabricated as circular membranes, 4 mm in diameter, thickness 60 microns, with a perforated area, 2 mm in diameter, in the centre. Three types of chips were fabricated utilizing anisotropic etching. The chips were glued with silicone

Coherent control of collective spontaneous emission in an extended atomic ensemble and quantum storage

Coherent control of collective spontaneous emission in an extended atomic ensemble resonantly interacting with single-photon wave packets is analyzed. A scheme for coherent manipulation of collective atomic states is developed such that superradiant states of the atomic system can be converted into subradiant ones and vice versa. Possible applications of such a scheme for optical quantum-state sto

Grade 3 ischemia on the admission electrocardiogram predicts rapid progression of necrosis over time and less myocardial salvage by primary angioplasty

Background: Among patients with ST-elevation acute myocardial infarction, those with terminal QRS distortion (grade 3 ischemia) have higher mortality and larger infarct size (IS) than patients without QRS distortion (grade 2 ischemia). Methods: We assessed the relation of baseline electrocardiographic ischemia grades to area at risk (AR) and myocardial salvage [100 (AR - IS)/AR] in 79 patients who

Investigation of the bond strength between the photo-sensitive polymer SU-8 and gold

We present the results from a thorough investigation of the bond strength between the photo-polymer SU-8 and Au. The data were obtained by pull-test experiments, below the glass transition temperature of the polymer. The different aspects that we investigated were: (i) the effect of using different adhesion promoters between the SU-8 and Au; (ii) the influence of the processing sequence, keeping e

Long-term efficacy of early versus delayed radiotherapy for low-grade astrocytoma and oligodendroglioma in adults: the EORTC 22845 randomised trial

Background Postoperative policies of "wait-and-see" and radiotherapy for low-grade glioma are poorly defined. A trial in the mid 1980s established the radiation dose. In 1986 the EORTC Radiotherapy and Brain Tumor Groups initiated a prospective trial to compare early radiotherapy with delayed radiotherapy. An interim analysis has been reported. We now present the long-term results. Methods After s

DNA analysis as a predictor of the outcome of induction chemotherapy in advanced head and neck carcinomas

We investigated whether flow cytometric DNA index and/or ploidy status are predictors of response to chemotherapy and survival. Fifty consecutive patients with previously untreated locally advanced squamous cell carcinomas of the head and neck received induction chemotherapy consisting of three courses of cisplatin (100 mg/m2) and a subsequent 120-hour infusion of fluorouracil (1000 mg/m2 per 24 h

Depletion Interactions in Model Microemulsions

The effects of temperature changes and polymer addition on the behavior of droplet microemulsions of nonionic surfactant, water, and decane are reported and analyzed within polymer depletion theory. Dilution viscometry and dynamic light scattering were used to confirm that these microemulsions behave essentially as hard-sphere dispersions, providing us with an ideal reference system. Addition of p

Epidermal growth factor induces cell proliferation in mouse pancreas and salivary glands

Epidermal growth factor (EGF) is a mitogenic stimulus in many tissues and occurs in large amounts in the pancreas and salivary glands. Whether EGF is mitogenic in the pancreas is controversial, and the EGF effect has not been studied in the salivary glands. Therefore, the aim of the present study was to investigate the possible effects on the pancreas and parotid and submandibular glands at differ

First human transplantation of a nonacceptable donor lung after reconditioning ex vivo.

Purpose. This article describes an ex vivo method to recondition and transplant rejected donor lungs. Description. A 19-year-old man was brain dead after a traffic accident. A roentgenogram showed bilateral lung contusion. He had ongoing intratracheal bleeding. After optimizing ventilator treatment and suctioning the airways, PaO2 was 9 kPa (67.5 mm Hg) on FiO(2) = 0.7. The lungs were rejected by

Antidiuresis therapy: Mechanism of action and clinical implications

Abnormalities of micturition occur in many different diseases, have a variety of causes and take several forms. This review will focus exclusively on those abnormalities in which antidiuretic therapy may be of benefit. These conditions are primarily characterized by an increase in the total amount of urine produced (polyuria) or a circadian shift in the control of urine production and/or voiding (

Influence of temperature on water and aqueous glucose absorption spectra in the near- and mid-infrared regions at physiologically relevant temperatures

Near- and mid-infrared absorption spectra of pure water and aqueous 1.0 g/dL glucose solutions in the wavenumber range 8000-950 cm(-1) were measured in the temperature range 30-42 C in steps of 2 degreesC. Measurements were carried out with an FT-IR spectrometer and a variable pathlength transmission cell controlled within 0.02 degreesC. Pathlengths of 50 mum and 0.4 mm were used in the mid- and n

Effects of acid concentration and solvent choice on enzymatic acrylation by Candida antarctica lipase B

Lipase-mediated acrylation is an attractive alternative to more traditional chemical processes, since it provides specific catalysis under mild conditions. A detailed study of the effects of solvent choice and substrate concentrations on the acrylation of octanol by Candida antarctica lipase B (Novozyme(R) 435) is presented. Acrylic acid was found to have a pronounced inhibitory effect. Partial ne

EPR Characterization of Photosystem II from Different Domains of the Thylakoid Membrane.

We report electron paramagnetic resonance (EPR) studies on photosystem II (PSII) from higher plants in five different domains of the thylakoid membrane prepared by sonication and two-phase partitioning. The domains studied were the grana core, the entire grana stack, the grana margins, the stroma lamellae and the purified stromal fraction, Y100. The electron transport properties of both donor and