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Coevolution with predators leads to the use of low-risk habitats by many prey species, which promotes survival during early developmental phases. These nurseries are valued by conservation and management agencies because of their contributions to adult populations. However, the physical and geographic characteristics, like shallow depths and isolation from other marine habitats, that restrict access to predators and thereby reduce risk to juvenile animals can also limit scientific research. Consequently, many nursery habitats are still unidentified and understudied. Here we used gillnet monitoring from 1982 to 2018 to delineate blacktip shark (Carcharhinus limbatus) nurseries in the north-western Gulf of Mexico and elucidated their physical, environmental and biological characteristics. Nursery habitats within estuaries (<2% of spatial area) were proximate to the Gulf of Mexico and exhibited significantly lower variability in salinity than non-nurseries. However, relative abundances of predators and prey were not significant delineators of nursery habitats. As such, food and risk may not influence juvenile blacktip habitat use as expected. Alternatively, reduced osmoregulatory stress attributed to predictable environments likely provides advantageous conditions for blacktips to develop foraging and antipredator tactics, which is vital prior to the winter migration of juvenile sharks into the Gulf of Mexico., (© 2022 Fisheries Society of the British Isles.)

Contactless measurements of water temperature are utilized in a number of sciences, such as oceanography, climatology, and biology. Previously reported Raman spectroscopy techniques exploited the changes in the shapes of water Raman bands. Interpretation of these changes is difficult since these bands are composed of multiple lines, each influenced not only by temperature but also by pressure and salinity. This paper presents a proof-of-principal demonstration of a contactless technique which determines water temperature from the ratio of Stokes and anti-Stokes intensities of the water 180 cm(-1) Raman band. This ratio is not sensitive to pressure and salinity, allowing reliable determination of water temperature.

A cylindrical sample cell is adapted to the problem of increasing the scattered-light signal from an optically thin liquid sample. The ends of the cylinder are coated with specularly reflecting aluminum to increase the signal by reflecting the stimulating light beam through the medium multiple times. The circumference of the cylinder is similarly coated to increase the fraction of the emitted light that is collected and sent into the slit of a spectrometer. Such a cell can greatly increase the signal measured by an analysis system without any modifications to the system.

Purpose: To determine whether well-described patterns of altered perfusion in schizophrenia can be identified by using continuous arterial spin labeling (CASL) with a whole-brain imaging sequence., Materials and Methods: This study was approved by the ethics committee of the local institutional review board, and written informed consent was obtained from all subjects. CASL was used to compare cerebral perfusion between 11 nonmedicated patients with schizophrenia and 25 healthy control subjects. Since antipsychotic medication may affect perfusion, only drug-free subjects were examined. Resting-state perfusion, as measured in terms of regional cerebral blood flow, was compared voxel wise by using an analysis of variance design in a statistical parametric mapping program, with patient age and sex as covariates., Results: Compared with the healthy control subjects, the schizophrenic patients had extensive areas of hypoperfusion in the frontal lobes bilaterally, in the anterior and medial cingulate gyri, and in the parietal lobes bilaterally. Increased perfusion was observed in the cerebellum, brainstem, and thalamus of the schizophrenic patients as compared with the perfusion in these areas in the control subjects., Conclusion: CASL in schizophrenia revealed patterns of hypo- and hyperperfusion similar to the perfusion patterns in previously published positron emission tomographic and single photon emission computed tomographic studies. The advantages of CASL, including independence from injected contrast agents, no irradiation, and fast acquisition time, may facilitate intensive perfusion studies of the early recognition of schizophrenia and other psychiatric disorders, as well as longitudinal disease-monitoring research of these conditions.

Hepatitis C virus (HCV), the leading cause for liver transplantation, is emerging as1 of the infections that pose public health problems in the world since about 170 million people worldwide are infected with this virus. Inequality in addressing racial/ethnic disparities in treatment for hepatitis C is a pressing problem. HCV is more common among African Americans than among other racial groups in the United States. Although African Americans have been shown to have a lower rate of viral clearance and a higher rate of chronic hepatitis C, they may have at the same time a much lower rate of fibrosis progression compared to Caucasians. The purpose of this study is to summarize treatment options available for hepatitis C in African Americans and to describe the different mechanisms thought to be the reasons for the disparate response to treatment in African Americans.

We present results of the design and testing of a modified optical Šolc notch filter for use in the deep ultraviolet (DUV, 190-300 nm) spectral range. The filter was designed to block a specific wavelength in this region. In addition, a sequence of blocked wavelengths occurs at wavelengths both shorter and longer than the specified wavelength. For Raman applications utilizing tunable lasers, the provision of multiple blocked wavelengths by a single filter may be especially useful. The filter design presented here produces extinction ratios >240 with transmission minima ~1 nm full width at half-maximum. Specific results are shown for the Raman spectra of Teflon excited at 248.4 nm.

The heat shock (HS) response is a phylogenetically ancient cellular response to stress, including heat, that shifts gene expression to a set of conserved HS protein (HSP) genes. In our earlier studies, febrile-range hyperthermia (FRH) not only activated HSP gene expression, but also increased expression of CXC chemokines in mice, leading us to hypothesize that the CXC chemokine family of genes might be HS-responsive. To address this hypothesis we analyzed the effect of HS on the expression of IL-8/CXCL-8, a member of the human CXC family of ELR(+) chemokines. HS markedly enhanced TNF-alpha-induced IL-8 secretion in human A549 respiratory epithelial-like cells and in primary human small airway epithelial cells. IL-8 mRNA was also up-regulated by HS, but the stability of IL-8 mRNA was not affected. TNF-alpha-induced reporter activity of an IL-8 promoter construct IL8(-1471/+44)-luc stably transfected in A549 cells was also enhanced by HS. Electrophoretic mobility and chromatin immunoprecipitation assays showed that the stress-activated transcription factor heat shock factor-1 (HSF-1) binds to at least two putative heat shock response elements (HSE) present in the IL-8 promoter. Deletional reporter constructs lacking either one or both of these sites showed reduced HS responsiveness. Furthermore, depletion of HSF-1 using siRNA also reduced the effects HS on TNF-alpha-induced IL-8 expression, demonstrating that HSF-1 could also act to regulate IL-8 gene transcription. We speculate that during evolution the CXC chemokine genes may have co-opted elements of the HS response to amplify their expression and enhance neutrophil delivery during febrile illnesses.

This is the second part of a two-part series on the clinical applications of high-field-strength (3.0-T) magnetic resonance (MR) imaging and spectroscopy. In this part, the current level of evidence regarding the use of higher magnetic field strengths for cardiac imaging techniques (including the assessment of cardiac anatomy and function), breast and pelvic imaging, musculoskeletal applications, pediatric imaging, and MR spectroscopy is presented. Published data are interpreted from the perspective of the clinical radiologist. Specific difficulties associated with high-field-strength MR for body imaging and for spectroscopic applications are reviewed and compared with the expected or documented added value of high-field-strength MR for clinical patient care. The overall number of studies published on clinical body high-field-strength MR is still small, and there is evidence for a clinical advantage for selected, but not all, body MR imaging applications. Even without published evidence, clinical experience suggests substantial clinical advantages for musculoskeletal and pediatric applications.

Objective: 99mTc-tetrofosmin and 99mTc-sestamibi are approved tracers for myocardial perfusion studies. Recently, a 99mTc-MIBI preparation from a different manufacturer (99mTc-cardiospect-MIBI) has been introduced to the market. Therefore, the aim of this study was the evaluation of 99mTc-tetrofosmin as well as of two different 99mTc-labeled MIBI tracers with regard to differences in imaging quality under resting conditions., Methods: Sixty patients (mean age 63.8 years +/- 1.25) with known or suspected coronary artery disease but without evidence of rest-ischemia were included. Twenty patients in each group were examined by a two-day-rest-stress protocol using the three 99mTc-labeled tracers. Visual analysis of all images was performed by two experienced physicians blinded with regard to the applied tracer. Regions of interest (ROI) were defined over the heart, lung and whole body only in the rest imaging in order to calculate heart-to-lung, lung-to-whole body-, and heart-to-whole body-ratios., Results: The heart-to-lung ratio was statistically significant higher for 99mTc-cardiospect-MIBI as compared to 99mTc-sestamibi as well as to 99mTc-tetrofosmin. Furthermore, a significantly higher heart-to-lung ratio was found for 99mTc-sestamibi as compared to 99mTc-tetrofosmin. The heart-to-whole body-ratio and the lung-to-whole body-ratio were equivalent between all tracers. Visual analysis revealed only slight differences regarding image quality between all tracers., Conclusions: ROI analysis surprisingly revealed a significant higher myocardial uptake and consequently a higher heart-to-lung ratio for 99mTc-cardiospect-MIBI. Whether this leads to a better visual image quality has to be evaluated in future studies with larger study populations as well as semiquantitative segmental analysis of the myocardial perfusion images.

Background: Miliary tuberculosis is a rare manifestation of tuberculosis with a high mortality rate. Diagnosis may easily be missed when severe neurologic symptoms are the first clinical manifestation. A typical case of miliary tuberculosis is reported, with special regard to the problems of diagnostic work-up. The need for an early empirical therapy for suspected military tuberculosis is emphasized in particular., Case Report: A 32-year-old Moroccan woman was admitted to the hospital with aphasia and a hemiparesis due to an intracerebral hemorrhage caused by a ruptured septic A. cerebri media aneurysm. Despite intensive work-up no septic focus could be found. Chest radiograph and computerized tomography (CT) showed miliary consolidations in the lungs. Skin testing (Tuberkulin Behring GT5) and smears for acid-fast bacilli and polymerase chain reaction (PCR) for tuberculosis of bronchoalveolar lavage (BAL) were negative. A four-drug antituberculous regimen (rifampicin [RMP], isoniazid [INH], pyrazinamide [PZA], ethambutol [EMB]) was initiated, and resulted in normalization of temperature, blood pressure, and C-reactive protein. Subsequently, cultures of BAL yielded Mycobacterium tuberculosis. The patient was discharged, a two-drug regimen was conducted (RMP, INH) after 2 months. Follow-up of the patient showed a significant improvement of the miliary lung consolidations after 5 months in CT of the lung. Only minor neurologic symptoms persisted after cessation of the therapy., Conclusion: In developed countries, miliary tuberculosis is a very rare cause of septic infiltrative lung disease. However, due to the nonspecific nature of the presentation and despite improved diagnostic techniques, a high clinical suspicion is essential for successful treatment.

We previously demonstrated that exposure to febrile-range hyperthermia (FRH) accelerates pathogen clearance and increases survival in murine experimental Klebsiella pneumoniae peritonitis. However, FRH accelerates lethal lung injury in a mouse model of pulmonary oxygen toxicity, suggesting that the lung may be particularly susceptible to injurious effects of FRH. In the present study, we tested the hypothesis that, in contrast with the salutary effect of FRH in Gram-negative peritonitis, FRH would be detrimental in multilobar Gram-negative pneumonia. Using a conscious, temperature-clamped mouse model and intratracheal inoculation with K. pneumoniae Caroli strain, we showed that FRH tended to reduce survival despite reducing the 3 day-postinoculation pulmonary pathogen burden by 400-fold. We showed that antibiotic treatment rescued the euthermic mice, but did not reduce lethality in the FRH mice. Using an intratracheal bacterial endotoxin LPS challenge model, we found that the reduced survival in FRH-treated mice was accompanied by increased pulmonary vascular endothelial injury, enhanced pulmonary accumulation of neutrophils, increased levels of IL-1beta, MIP-2/CXCL213, GM-CSF, and KC/CXCL1 in the bronchoalveolar lavage fluid, and bronchiolar epithelial necrosis. These results suggest that FRH enhances innate host defense against infection, in part, by augmenting polymorphonuclear cell delivery to the site of infection. The ultimate effect of FRH is determined by the balance between accelerated pathogen clearance and collateral tissue injury, which is determined, in part, by the site of infection.

Purpose: 1) To evaluate feasibility of sensitivity encoding (SENSE) for high spatial resolution intracranial 3D time-of-flight (TOF) MR angiography at 3.0 T using a 1024 imaging matrix and 2) to compare image quality and diagnostic yield with 3.0 T TOF MRA without SENSE., Methods: In a prospective study TOF MR angiography of the circle of Willis was performed with SENSE in 24 patients on a clinical whole body 3.0 T MR system (Intera, Philips Medical Systems, NL). In the SENSE protocol (S-MRA), a SENSE factor of 2.5 was used to shorten acquisition time and to increase the anatomic coverage (5:12 min.; 150 slices). A matrix of 832 x 572 was acquired and reconstructed to 1024 yielding a non-zerofilled voxel size of 0.30 x 0.44 x 1.00 mm(3) (0.13 mm(3)). Two readers were asked to review the images regarding the presence of vascular disease, and to rate, in consensus, the quality of the angiograms on a 5-point scale (5 = excellent through 1 = non-diagnostic). Results were compared with the results in 15 subjects who underwent intracranial TOF MRA at 3.0 T without SENSE (NS-MRA: acquisition time, 7:57 min.; 100 slices). Digital subtraction angiography (DSA) served as standard of reference in the 4/24 patients in whom vascular disease was identified., Results: S-MRA at 3.0 T was judged to provide image quality that was adequate for diagnosis or better in 24/24. Median score of image quality of S-MRA and NS-MRA were 5 and 5, respectively. In the 4 patients with DSA correlation, a total of 8 pathologic findings (7 steno-occlusive diseases, 1 aneurysm) were correctly identified on S-MRA., Conclusion: The use of SENSE for intracranial TOF MRA at very high imaging matrix is feasible at 3.0 T. Compared to the imaging technique without SENSE, it allows TOF MRA with substantially reduced acquisition time, and with substantially increased anatomic coverage while maintaining image quality of NS-MRA.

The applicability of functional magnetic resonance imaging (fMRI) in patients with Alzheimer's disease (AD) or schizophrenia is frequently limited by cognitive impairment, which prevents the adequate execution of complex tasks. An experimental design that puts only minor demands on the patients' cognitive ability but engages disease-relevant brain structures would be of benefit. Novelty detection and repetition suppression are two basic components of memory that might be used to investigate specific brain areas under these conditions. Novelty detection has been related to hippocampal activation increases. Stimulus repetition related activation decreases (suppression) have been observed in the extrastriate cortex and have been related to perceptual priming. Both processes have been examined primarily in neuroimaging studies with complex cognitive tasks. We used event-related fMRI to investigate novelty- and repetition-related effects in an attended but passive picture-viewing task in healthy subjects. The differential activation, detected in the novel vs. repeated contrast, was located in the bilateral anterior hippocampus and in bilateral occipital and inferior-temporal areas. The hippocampal activation is of interest because medial temporal lobe lesions are key features in AD and schizophrenia. The repetition-related activation decreases in the extrastriate areas are of potential value in investigating the conflicting results regarding perceptual priming impairment in both disorders. Our results indicate that activation of disease-relevant brain regions under passive task conditions is possible. This might increase the utility of functional imaging in cognitively impaired patients., (Copyright 2002 Wiley-Liss, Inc.)

Objective: To detect regional metabolic changes that resemble the expected spatial pattern of neuronal loss in patients with Alzheimer disease (AD)., Methods: Thirty-four patients with AD and 22 healthy control subjects were included in the study. Single-slice fast proton spectroscopic imaging was performed in parallel angulation to the temporal lobes. Proton spectra were selected from the hippocampus, the lateral temporal lobe, and the occipital lobe of both hemispheres to determine metabolite concentration of N-acetylaspartate (NAA), total creatine (tCr), including phosphocreatine and creatine, and choline-containing compounds (Cho). The metabolic ratios of NAA/tCr and Cho/tCr were calculated and compared between patients with AD and healthy volunteers., Results: The NAA/tCr ratios were significantly reduced in the left (F(1,1) = 4.34, P =.04) and right hippocampus (F(1,1) = 9.96, P =.003) in patients with AD. The Cho/tCr ratios remained unchanged in both hippocampi. There was no significant change of either NAA/tCr or Cho/tCr in the lateral temporal and occipital lobes of patients with AD., Conclusion: This study provides evidence that fast proton spectroscopic imaging may detect the regional pattern of disturbed neuronal integrity in patients with AD with high spatial resolution in a short acquisition time.

The differential neuronal activation related to encoding of novel and recognition of previously studied items and the effect of retrieval effort on neuronal activation were assessed in a event-related functional magnetic resonance imaging experiment. A verbal continuous recognition task with two repetitions of the target items was used. The interpretation of the results was focused on brain areas that have been previously reported to be involved in explicit memory. Encoding of novel words in comparison with the first repetition was associated with a stronger activation in the left parahippocampal and inferior frontal gyrus. Encoding of novel words compared to the second repetition was related to a greater bifrontal activation. Recognition of studied items was associated with greater activation in the medial and bilateral inferior parietal lobe at first repetition and in the medial and left inferior parietal lobe at second repetition in comparison with encoding of the novel items. Recognition at first repetition compared to recognition at second repetition was associated with greater bilateral frontal activation. The results are discussed in relation to current concepts of spatial differentiation of memory function and findings from event-related potentials studies of continuous recognition.

We performed high-intensity subpicosecond laser-plasma interaction experiments to examine nonlinear scattering mechanisms in underdense plasmas. At incident laser intensities of 2 x 10(18) W/cm(2) the stimulated-Raman-backscattered spectrum exhibited an extremely broad, supercontinuumlike structure (Deltaomega/omega(0) > 1) extending from ~500 to >1200 nm (limited only by detector sensitivity). Large-amplitude modulations in the spectrum of the backscattered light were measured and are attributed to an interaction of the stimulated-Raman-scattered radiation with ion plasma waves.

Subpicosecond laser pulses at power levels in excess of 1 TW were channeled through hollow microcapillary tubes by use of a combination of grazing-incidence dielectric and plasma-wall reflection mechanisms. Maximum input and output intensities were 10(17) and 10(16) W/cm(2) through 50-microm radius by 3-cm-long glass microcapillary tubes with as few as two waveguide modes being excited. 133-microm radius tubes as long as 13 cm resulted in successful channeling with an extinction coefficient of 0.2 cm(-1) and a plasma-wall reflectivity of 80%.