Approaching the transit time limit for high-precision spectroscopy on metastable CO around 6 µm.

As molecular spectroscopy makes its comeback to the limelight of fundamental sciences, scientists need ever better coherent light sources and diagnostic methods. Of particular importance for molecular spectroscopy is the mid infrared spectral region, where strong and narrow ro-vibrational excitations have their fundamental transition frequencies. Unfortunately, much technology in some portions of this spectral region is still rather pioneering. Here we present a high-resolution spectroscopy experiment, based on a molecular beam setup, which pushes the measured linewidth close to the transit time limit, on the order of 100 kHz. Moreover, we discuss the issue of frequency-noise characterization and the linewidth measurement of the ultrastable infrared laser used in the experiment.

Measuring molecular frequencies in the 1-10 µm range at 11-digits accuracy.

High-resolution spectroscopy in the 1-10 µm region has never been fully tackled for the lack of widely-tunable and practical light sources. Indeed, all solutions proposed thus far suffer from at least one of three issues: they are feasible only in a narrow spectral range; the power available for spectroscopy is limited; the frequency accuracy is poor. Here, we present a setup for high-resolution spectroscopy, whose approach can be applied in the whole 1-10 µm range. It combines the power of quantum cascade lasers (QCLs) and the accuracy achievable by difference frequency generation using an orientation patterned GaP crystal. The frequency is measured against a primary frequency standard using the Italian metrological fibre link network. We demonstrate the performance of the setup by measuring a vibrational transition in a highly-excited metastable state of CO around 6 µm with 11 digits of precision.

Imaging cold molecules on a chip.

We present the integrated imaging of cold molecules in a microchip environment. The on-chip detection is based on resonance-enhanced multiphoton ionization, which is quantum state selective and generally applicable. We demonstrate and characterize time-resolved spatial imaging and subsequently use it to analyze the effect of a phase-space manipulation sequence aimed at compressing the velocity distribution of a molecular ensemble with a view to future high-resolution spectroscopic studies. The realization of such on-chip measurements adds the final fundamental component to the molecule chip, offering a new and promising route for investigating cold molecules.

Functional evaluation and rehabilitation engineering.

Life is complex and all about movement, which allows us to interact with the environment and communicate with each other. The human nervous system is capable of performing a simultaneous and integrated control of 100-150 mechanical degrees of freedom of movement in the body via tensions generated by about 700 muscles. In its widest context, movement is carried out by a sensory motor system comprising multiple sensors (visual,auditory, and proprioceptive),multiple actuators (muscles acting on the skeletal system),and an intermediary processor that can be summarized as a multiple-input­multiple-output nonlinear dynamic time-varying control system. This grand control system is capable of responding with remarkable accuracy,speed, appropriateness,versatility, and adaptability to a wide spectrum of continuous and discrete stimuli and conditions and is certainly orders of magnitude more complex and sophisticated than the most advanced robotic systems currently available. In the last decades,a great deal of research has been carried out in the fields of functional evaluation of human performance and rehabilitation engineering. These fields combine knowledge, concepts, and methods from across many disciplines (e.g., biomechanics,neuroscience, and physiology), with the aim of developing apparatuses and methods fort he measurement and analysis of complex sensory motor performance and the ultimate goal of enhancing the execution of different tasks in both healthy people and persons with reduced capabilities from different causes (injury, disease, amputation,and neural degeneration).

Vibrational signatures of hydrogen bonding in the protonated ammonia clusters NH4(+)(NH3)(1-4).

The gas phase vibrational spectroscopy of the protonated ammonia dimer N(2)H(7)(+), a prototypical system for strong hydrogen bonding, is studied in the spectral region from 330 to 1650 cm(-1) by combining infrared multiple photon dissociation and multidimensional quantum mechanical simulations. The fundamental transition of the antisymmetric proton stretching vibration is observed at 374 cm(-1) and assigned on the basis of a six-dimensional model Hamiltonian, which predicts this transition at 471 cm(-1). Photodissociation spectra of the larger protonated ammonia clusters NH(4)(+)(NH(3))(n) with n=2-4 are also reported for the range from 1050 to 1575 cm(-1). The main absorption features can be assigned within the harmonic approximation, supporting earlier evidence that hydrogen bonding in these clusters is considerably weaker than for n=1.

Functional assessment of the lumbar spine through the optoelectronic ZooMS system. Clinical application.

AIM: The radiographic method remains the main imaging technique for the physiological, anatomical and possibly pathological analysis of the spine thanks to its ease of use, precision and reliability. Despite this, the technique is inadequate for functional and dynamic studies. This paper aims to apply a dedicated noninvasive methodology based on optoelectronic techniques for the functional evaluation of the lumbar spine. METHODS: A reference data set for typical movements (i.e. flexion/extension, lateral bending, axial rotation) of the lumbar spine has been developed. Twenty healthy subjects have been recruited (10 males and 10 females) to create the databases of healthy subjects; one subject who suffers from lumbar spine diseases has been analyzed and his mobility has been compared to healthy subjects. RESULTS: Two databases have been created: in the former, the entire movement is normalized in time with respect to its duration; in the latter, all movements are classified in characteristic phases and each single phase is normalized to a defined duration. These databases include both the global movement of the lumbar tract of the spine and the movement of the single functional units (2 vertebrae, the intervertebral disk and the intervening surrounding soft tissues). Moreover, these databases are divided into male and female databases according to the natural differences in range of motion and pattern of movement. A clinical application for pathologic subjects is shown demonstrating the applicability and usability of this protocol. CONCLUSION: This method allows to assess both the quality and the quantity of lumbar spine movement (both global and metameric level) of the subject and to distinguish the patient from the healthy subject.

Isomorphous substitution in bimetallic oxide clusters.

The geometric and electronic structure of bimetallic oxide clusters is studied as a function of their composition with gas phase vibrational spectroscopy. Infrared multiple photon dissociation spectra of titanium-vanadium oxide cluster anions are measured in the 500 to 1200 wave number range and assigned on the basis of harmonic frequencies calculated using density functional theory. Singly substituted (V(2)O(5))(n-1)(VTiO(5))(-) (n=2-4) cluster anions are shown to form polyhedral caged structures similar to those predicted for their isoelectronic counterparts, the neutral (V(2)O(5))(n) clusters. Upon systematic exchange of V by Ti atoms in V(4-n)Ti(n)O(-)(10) (n=1-4), the structure does not change. The stress induced by the isomorphous substitution results in an increased number of unpaired electrons (n-1) for the Ti-rich systems, leading to a quartet ground state for Ti(4)O(-)(10).

Evaluation of head-to-trunk control in whiplash patients using digital CranioCorpoGraphy during a stepping test.

We used digital-CranioCorpoGraphy (dCCG) to document whiplash effects on head-on-trunk stabilization while subjects walked on the spot (Fukuda test). Twenty-five healthy subjects were compared with 33 whiplash patients. Whiplash patients were classified as chronic (more than 6 months after injury) and recent (less than 6 months after injury). Clear differences between healthy subjects and patients were seen and three different strategies were detected. Pattern A appeared similar to normals but quantitative analysis showed significant differences with paradoxical head over-stabilization (collar-effect); pattern B decreased head stability; pattern C decreased head stabilization with reduced displacements of the body. Due to the complexity of the data analyzed for each marker, a coefficient of performance (CP) was calculated to simplify the cut-off between normal and pathological tests. CP clearly identified an abnormal stepping pattern. Our findings indicate that firstly dCCG identified a specific vestibular task in whiplash patients, secondly whiplash did not always provoke vestibular involvement and thirdly dCCG could be a tool to discriminate patients with and without vestibular involvement after whiplash.

ZooMS: a non invasive analysis of global and metameric movement of the lumbar spine.

AIM: The assessment of spine mobility is an important parameter to define its functionality. In the last decades a lot of research has been carried out mainly through radiographic investigations; non invasive methods demonstrated not to be sufficiently accurate, not to allow free movement, not to provide metameric assessment and suitable for everyday clinical practice. The aim of this study is the development of a new experimental non invasive protocol, called Zoom on mobility of the spine (ZooMS) to assess the mobility of lumbar spine, from the 11th thoracic to the sacrum bone and the pelvis, with the possibility of identifying the metameric contribution of each rotation around all the axes correlated to the global movement. METHODS: We developed a dedicated non invasive methodology based on optoelectronic techniques for 3D target recording to be applied to the functional evaluation of the mobility of the lumbar spine in young healthy males. Ten subjects participated in the method validation, performing free rotations (flexion/extension, lateral bending and axial rotation) from standing to the maximum excursion and back. RESULTS: The comparison of the range of motion (RoM) with those presented in literature was satisfactory, although some differences were shown (above all in axial rotation, which however gives the minor contribution to the mobility of the lumbar spine). The validation of the protocol was successful in terms of intraoperator, interoperator and circadian remarking, the 3 factors eventually affecting its repeatability. CONCLUSION: The RoM of the whole lumbar spine and of each functional unit, together with the pattern of movement may so represent an innovative and important aspect in clinical applications.

Correlation between clinical characteristics and proliferative activity in patients with craniopharyngioma.

OBJECTIVES: The aim of the study was to correlate the Ki-67 and cyclin A labelling index (LI) with clinical characteristics and risk of recurrence of craniopharyngiomas. METHODS: 47 consecutive patients were studied, 21 female and 26 male, aged 34.3 (2.8) years. Immunohistochemical analysis was performed on paraffin wax embedded material using monoclonal antibodies directed against the proliferation associated nuclear antigen Ki-67 and cyclin A. RESULTS: The median Ki-67 LI was 8.6% (interquartile range, 4.4%-14.0%). Ki-67 LI was significantly higher in tumours with a heavy inflammatory reaction and diabetes insipidus at presentation, whereas other clinical and histological features were not associated with the proliferation index. There was a strong linear correlation between Ki-67 LI and cyclin A LI (r = 0.77; p<0.0001); therefore, cyclin A LI showed the same clinical and histological relations described for Ki-67 LI. Recurrence of craniopharyngioma occurred in 13 of 46 patients (28.3%). The median Ki-67 LI in the 13 recurrent craniopharyngiomas (9.0%) was not significantly different from that of non-recurring tumours (7.9%). Cyclin A LI was also not associated with the risk of relapse. CONCLUSIONS: This study confirms the great variability of proliferative activity in craniopharyngiomas. Ki-67 and cyclin A LIs were associated with the presence of a heavy inflammatory reaction and diabetes insipidus, but did not correlate with the long term risk of tumour regrowth.

Short-term effects of "botulinum toxin a" as treatment for children with cerebral palsy: kinematic and kinetic aspects at the ankle joint.

Botulinum toxin A (BTA) therapy plays several roles in the management of paediatric cerebral palsy (CP). However, few studies contain objective documentation of gait changes. The main aim of this study was to provide objective information on the outcome of the treatment. Gait analysis data from 20 normal subjects and 23 CP children were collected before and after BTA injections into the gastrocnemius-soleus complex. The follow up was performed 1 month after the first injection. The kinematic and kinetic data revealed significant improvements in dynamic ankle dorsiflexion, both in stance and in the swing phase, an improvement of equinus foot upon initial contact and better support in stance. The results of this study are promising, but studies of other joints involved in gait, such as the knee, are also needed.

Incorrect echocardiographic diagnosis in patients with mechanical prosthetic valve dysfunction: correlation with surgical findings.

PURPOSE: To identify the rate of occurrence and type of incorrect echocardiographic diagnoses in patients with mechanical valve prostheses. PATIENTS AND METHODS: We studied 170 consecutive patients (73 women and 97 men) with a total of 208 prostheses who underwent surgery for mitral (n = 136) or aortic (n = 72) valve dysfunction between January 1991 and December 1997. Preoperative echocardiographic data were compared with surgical findings. Any major discrepancy between the echocardiographic reports and surgery was judged to be unconfirmed when the preoperative echocardiographic diagnosis was not confirmed at surgery, but the prosthesis was found to be dysfunctioning; and was judged to be erroneous when the preoperative echocardiographic diagnosis was not confirmed, and surgical inspection failed to reveal any other prosthetic abnormality. RESULTS: There were 25 (12%) diagnostic errors. Of the 136 mitral prostheses, there were 9 unconfirmed diagnoses of paravalvular regurgitation (6 had a fibrous tissue overgrowth, 1 had a thrombus with fibrous tissue overgrowth, 1 had endocarditis vegetations, and 1 had a ball variance) and 5 erroneous diagnoses. Eleven diagnostic errors were made in the 72 aortic prostheses: there were 9 unconfirmed diagnoses (paravalvular regurgitation was diagnosed as transvalvular in 7, and transvalvular regurgitation as paravalvular in 2 cases), and 2 erroneous diagnoses. CONCLUSIONS: Although echocardiography has gained great credibility among clinicians, special care should be taken when assessing patients in whom prosthetic valve dysfunction is suspected.

Expression of a highly conserved protein, p27BBP, during the progression of human colorectal cancer.

The highly conserved protein p27BBP is a cytoplasmic interactor of integrin beta4 expressed in epithelia. p27BBP is found in two pools: one nuclear pool enriched in the perinucleolar region, and one cytoplasmic pool. Deletion of p27BBP in yeast is lethal as a result of loss of the ribosomal 60S subunit. The aim of this study was to investigate the distribution of p27BBP in gut epithelium and its behavior during progression of human colorectal carcinomas. Results indicated that p27BBP is high in rapidly cycling cells and decreased in villous cells committed to apoptotic cell death. In dysplastic adenomas and carcinomas, p27BBP displayed a large increase of its nucleolar component that was superimposable to argyrophylic nucleolar organizing region-associated proteins and was associated with the nuclear matrix. Western blotting confirmed increased p27BBP in dysplastic adenomas and in carcinomas. In particular, p27BBP increased progressively from adenomas to carcinomas and, in the latter, was related to the tumor stage. The overexpression of p27BBP corresponded to mRNA up-regulation in carcinomas, supporting the idea of transcriptional or post-transcriptional regulation of its expression. Results suggested that p27BBP alterations are an early event in the transition from benign to malignant colorectal phenotypes and provide a novel tool in surgical pathology.

Staining apoptosis in paraffin sections. Advantages and limits.

OBJECTIVE: To describe the advantages and limits of apoptosis detection on paraffin sections by TdT-mediated dUTP nick end labeling (TUNEL). STUDY DESIGN: Two hundred sixty-five paraffin-embedded samples from malignant and benign human tissue were analyzed by TUNEL. Also, biparametric analysis of apoptosis and proliferation index (MIB-1), apoptosis, cytokeratin or leukocyte common antigen was performed. RESULTS: Our preliminary conclusions are as follows. The limits are that this labelling method might detect cells that have not shown DNA fragmentation specific for apoptosis only. The technique is extremely sensitive to the degree of proteolytic digestion. TUNEL identifies nuclei in areas of necrosis. Indeed, the staining of necrotic areas of tissue with the in situ labelling method should not cause confusion since simple morphologic examination of tissues will suffice to identify areas of necrotic cells. The advantages are that TUNEL is a method of simplifying the identification of apoptotic nuclei in routinely processed tissue sections, maintaining topography. It allows retrospective studies and biparametric analysis of cell death and proliferation on the same sample. Furthermore, with biparametric stain, it could better identify the origin (epithelial, mesenchymal, and so on) of apoptotic cells. CONCLUSION: TUNEL is a good method of detecting apoptotic nuclei in fixed, embedded tissue sections, but, because of the limits of the method, the results should be interpreted in conjunction with apoptosis assessment by routine light microscopy.

Antihypertensive efficacy of angiotensin converting enzyme inhibition and aspirin counteraction.

OBJECTIVE: Blockade of bradykinin breakdown and enhancement of prostaglandin release probably participate in the antihypertensive activity of angiotensin converting enzyme (ACE) inhibitors. Cyclooxygenase blockers may attenuate the efficacy of ACE inhibitors by interfering with prostaglandin synthesis, and patients taking aspirin may not benefit from ACE inhibition. This study was designed to evaluate the incidence of the counteractive phenomenon and to define minimal aspirin dosage that causes an antagonistic effect. METHODS: These were 26 patients with mild to moderate hypertension (group 1) and 26 patients with severe untreated primary hypertension (group 2). Enalapril (20 mg twice a day) was used as a single drug in group 1 and was added to the combination of long-acting nifedipine (30 mg/day) and atenolol (50 mg/day) in group 2. Aspirin was tested at doses of 100 and 300 mg/day, and an attenuation of more than 20% of the mean blood pressure decrease produced by enalapril was the criteria that defined antagonism. RESULTS: The 100 mg dose was ineffective. However, 300 mg aspirin had an antagonistic effect in 57% of patients in group 1 and 50% of patients in group 2: mean arterial pressure was lowered by 63% and 91% less, respectively. Results were independent of the drug administration order. In "responders," aspirin significantly attenuated the renin rise associated with ACE inhibition. CONCLUSIONS: These findings suggest that a number of ACE-inhibited patients are susceptible to 300 mg/day aspirin, regardless of hypertension severity. Antagonism may be mediated through prostaglandin inhibition according to predominance, in an individual patient, of prostaglandin activation (also as a renin secretory stimulus) or angiotensin blockade by enalapril.

Cell loss and proliferation in non-small cell lung carcinoma: correlation with histological subtype.

BACKGROUND: Cell kinetic data are important indicators of the aggressiveness of tumor and treatment response. The size of a neoplasm depends on the balance between cell proliferation and death. Thus, the analysis of the kinetics of cell proliferation and death may explain differences in the rates of tumour progression. METHODS: We studied apoptosis and proliferative indices in 95 cases of non-small cell lung carcinomas. The analysis was performed on paraffin-embedded tissue, by both MIB-1 immunocytochemical detection to establish the proliferation index and the in-situ end labelling method for the apoptosis index. The two indices were related. RESULTS: Our results showed a high proliferative index and cell loss rate in squamous cell carcinoma, and a low proliferative index and cell loss rate in adenocarcinoma, suggesting two different growth patterns. CONCLUSION: These findings could explain the different biological behaviour and treatment response of the tumours. The tendency of a cancer cell to undergo apoptosis may be especially important for the chemotherapy of malignant tumours with a low growth rate, which are typically resistant to cytostatic agents.

[The antagonistic effect of aspirin on the expression of prostaglandin participation in the antihypertensive activity of ACE inhibitors]. / Effetto controattivo dell'aspirina quale espressione della partecipazione prostaglandinica all'attività antipertensiva dell'ACE-inibizione.

ACE-inhibitors antagonize both angiotensin production and bradykinin breakdown, resulting in enhancement of vasodilating prostaglandin release. This provides an explanation for the experimental observation that cycloxygenase blockers (such as aspirin or indomethacin) may counteract the antihypertensive efficacy of the ACE-inhibitors; it may be also possible that hypertensive patients taking aspirin as an antiplatelet agent may fail to benefit from ACE-inhibition. This study was aimed at: evaluating the magnitude and incidence of the inhibitory phenomenon; defining the minimal aspirin dosage that produces an antagonistic effect, as well as the possible reasons for a different individual susceptibility. We have studied untreated patients with mild (10 cases, Group 1), moderate (16 cases, Group 2) or severe (26 cases, Group 3) hypertension. The ACE-inhibitor enalapril was used at doses of 10 mg bid (groups 1 and 2) or 20 mg bid (Group 3). Active drug treatment periods had a 5-day duration. A daily dose of aspirin of 100 mg had no effect on the antihypertensive efficacy of enalapril. On the contrary, when a dose of 300 mg was used, 60, 57 and 50% of patients in Group 1, 2 and 3, respectively, showed a > 20% restraint of the mean arterial pressure fall with enalapril (20% was the lower arbitrary limit for defining antagonism). Inhibition was independent of the sequence of drug administration. In these patients counteraction averaged 60, 70 and 90%, respectively. In them, and not in the remaining patients in each group, aspirin substantially attenuated the renin rise elicited by ACE-inhibition. These data suggest that: a dosage of 100 mg aspirin is devoid of any inhibitory effect; more that 50% of ACE inhibited patients are, at least in the short term, susceptible to the action of 300 mg aspirin, regardless of the severity of hypertension; counteraction is seemingly mediated through a prostaglandin inhibition and depends on the individual predominance of prostaglandin activation (also as a renin secretory stimulus) or angiotensin inhibition by the ACE-inhibitor.

Breast carcinoma detection with a combination of radiolabeled monoclonal antibodies. Promising results from immunohistochemistry studies.

BACKGROUND: Recent studies have demonstrated that the use of radiolabeled monoclonal antibodies (MoAbs) directed against tumor-associated antigens could help in the recognition of primary tumors, their extent, and their metastases by external scintigraphy (used preoperatively) or by hand-held gamma-detecting probe (GDP) (used intraoperatively). METHODS: The authors evaluated carcinoembryonic antigen (CEA), c-erb B-2 protein, and TAG-72 expression in 100 cases of breast carcinoma using F023C5 (anti-CEA), B72.3, and anti-c-erb B-2 protein MoAbs that were previously investigated for their usefulness in radioimmunoguided surgery and external scintigraphy. The goal of this study was to examine the biodistribution of each antibody in primary, multifocal, and metastatic lesions to evaluate the suitability of their simultaneous use in GDP and external scintigraphy. RESULTS: Results showed immunoreactivity for c-erb B-2 protein in 39 of 99 cases, for B72.3 in 41 of 100 cases, and for CEA in 15 of 100 cases. Multifocal lesions demonstrated positivity for c-erb B-2 protein in 37.4% of cases (6 of 16), for B72.3 in 68.8% of cases (11 of 16), and for CEA in 6.2% of cases (1 of 16). In lymph node metastases, immunoreactivity was found for c-erb B-2 protein in 36.4% of cases (12 of 33), for B72.3 in 63.7% of cases (21 of 33), and for CEA in 24.3% of cases (8 of 33). When the authors considered the immunoreactivity of all three MoAbs, the percentage of positive cases they observed was 60% in primary tumors (60 cases), 78% in lymph node metastases, and 81.2% in multifocal lesions. CONCLUSIONS: These results suggest that in vivo tumor radioimmunodetection could be improved by the use of more antibodies directed against different tumor-associated antigens.

Effects of an acute increase in plasma triglyceride levels on glucose metabolism in man.

The aim of the study was to evaluate the effects of an acute increase in triglyceride levels induced by Intralipid (Kabivitrum, Stockholm, Sweden) infusion on forearm glucose uptake, glucose oxidative metabolism, and hepatic glucose production independent of circulating free fatty acid (FFA) levels in man. Six normal subjects underwent three different tests in random order. Each test consisted of a control period of 120 minutes followed by a euglycemic, hyperinsulinemic clamp lasting 120 minutes. In test 1, a high-dose intravenous Intralipid infusion was performed to increase triglyceride and FFA levels. In test 2, heparin (30 U/min) plus low-dose Intralipid infusions were performed to maintain triglyceride at normal levels and increase only FFA levels. Test 3 was performed as a control study. During the 120-minute control period, forearm glucose uptake and hepatic glucose production were not affected by increasing only FFA levels (test 2) or FFA and triglyceride levels (test 1) as compared with the control study. On the contrary, glucose oxidation was significantly decreased as compared with the control study during tests 1 and 2, without a further significant decrease during simultaneously increased FFA and triglyceride levels. Concomitantly, lipid oxidation was similar in tests 1 and 2, at values significantly greater than in test 3. During the euglycemic clamp, forearm glucose uptake and glucose oxidation were significantly lower during tests 1 and 2 than test 3. At variance with the control period, the increase of triglyceride levels during test 1 caused a significant 30% to 40% decrease of both parameters as compared with test 2.(ABSTRACT TRUNCATED AT 250 WORDS)