Analysis of small-scale soil CO2 fluxes in an orange orchard under irrigation and soil conservative practices

The quantification of soil carbon dioxide (CO2) flux represents an indicator of the agro-ecosystems sustainability. However, the monitoring of these fluxes is quite challenging due to their high spatially-temporally variability and dependence on environmental variables and soil management practices.In this study, soil CO2 fluxes were measured using a low-cost accumulation chamber, that was realized ad hoc for the surveys, in an orange orchard managed under different soil management (SM, bare versus mulched soils) and water regime (WR, full irrigation versus regulated deficit irrigation) strategies. In particular, the soil CO2 flux measurements were acquired in discontinuous and continuous modes, together with ancillary agrometeorological and soil-related information, and then compared to the agrosystem scale CO2 fluxes measured by the eddy covariance (EC) technique.Overall significant differences were obtained for the soil CO2 discontinuous fluxes as function of the WR (0.16 ± 0.01 and 0.14 ± 0.01 mg m-2 s-1 under full irrigation and regulated deficit irrigation, respectively). For the continuous soil CO2 measurements, the response observed for the SM factor varied from year to year, indicating for the overall reference period 2022-23 higher soil CO2 flux under the mulched soils (0.24 ± 0.01 mg m-2 s-1) than under bare soil conditions (0.15 ± 0.00 mg m-2 s-1). Inter-annual variations were also observed as function of the day-of-year (DOY), the SM and their interactions, resulting in higher soil CO2 flux under the mulched soils (0.24 ± 0.02 mg m-2 s-1) than under bare soil (0.15 ± 0.01 mg m-2 s-1) in certain periods of the years, according to the environmental conditions.

Results

suggest the importance of integrating soil CO2 flux measurements with ancillary variables that explain the variability of the agrosystem and the need to conduct the measurements using different operational modalities, also providing for night-time monitoring of CO2. In addition, the study underlines that the small-scale chamber measurements can be used to estimate soil CO2 fluxes at orchard scale if fluxes are properly scaled.

A Modified Corona Score Using Lung Ultrasound to Identify COVID-19 Patients

BACKGROUND

COVID-19 continues to circulate around the world with multiple different strains being active at once. While diagnosis with antigen and molecular testing is more readily available, there is still room for alternative methods of diagnosis, particularly in out-of-hospital settings, e.g., home or nursing homes, and in low-medium income countries, where testing may not be readily available.

STUDY OBJECTIVES

To evaluate the performance of two modified corona score methods compared with a traditional corona score approach to identify patients with COVID-19.

METHODS

This was a retrospective multicenter study performed to compare the ability to predict SARS-CoV-2 test results on a nasopharyngeal swab between the corona scores and two novel corona scores (modified 1 corona score (M1CS) and modified 2 corona score (M2CS)). The M1CS included lung ultrasound (LUS) and chest X-ray (CXR) results, while the M2SC only utilized LUS findings without CXRs. Emergency physicians performed point-of-care LUS and a physical examination upon admission to the emergency department.

RESULTS

Subjects positive for SARS-CoV-2 were older and had higher ferritin levels and temperature and lower diastolic blood pressure and oxygen saturation. The two groups differed on corona score and modified corona scores (p < 0.001 for all). SARS-CoV-2-positive patients had fewer pleural line irregularities (p = 0.025) but presented more frequently with an interstitial pattern on CXRs (p < 0.001).

CONCLUSIONS

In our study, LUS alone provided a valuable contribution to the corona score and improved its performance more than when CXR results were included. These results suggest that resource-limited areas where CXRs may be unavailable or prohibitively expensive can utilize an ultrasound as the sole imaging modality without a loss of diagnostic performance for SARS-CoV-2 pneumonia diagnosis.

Early Lung Ultrasound Findings in Patients With COVID-19 Pneumonia: A Retrospective Multicenter Study of 479 Patients

OBJECTIVES

Lung ultrasound (LUS) holds the promise of an accurate, radiation-free, and affordable diagnostic and monitoring tool in coronavirus disease 2019 (COVID-19) pneumonia. We sought to evaluate the usefulness of LUS in the diagnosis of patients with respiratory distress and suspicion of interstitial severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia, in comparison to other imaging modalities.

METHODS

This was a multicenter, retrospective study. LUS was performed, on Emergency Department (ED) arrival of patients presenting for possible COVID-19 evaluation, by trained emergency physicians, before undergoing conventional radiologic examination or while waiting for the report. Scans were performed using longitudinal transducer orientation of the lung regions. CXR was interpreted by radiologists staffing ED radiology. Subjects were divided into two group based on molecular test results. LUS findings were compared to COVID test results, nonlaboratory data, and other imaging for each patient. Categorical variables were expressed as percentages and continuous variables as median ± standard error.

RESULTS

A total of 479 patients were enrolled, 87% diagnosed with SARS-CoV-2 by molecular testing. COVID positive and COVID negative patients differed with respect to sex, presence of fever, and white blood cells count. Most common findings on lung point of care ultrasound (POCUS) for COVID-positive patients were B-lines, irregular pleural lines, and small consolidation. Normal chest X-ray was found in 17.89% of cases.

CONCLUSIONS

This 479 patient cohort, with COVID-19, found LUS to be noninferior to chest X-ray (CXR) for diagnostic accuracy. In this study, COVID-positive patients are most likely to show B lines and sub-pleural consolidations on LUS examination.

Neuroradiologic Phenotyping of Galactosemia: From the Neonatal Form to the Chronic Stage

Galactosemia is a rare genetic condition caused by mutation of enzymes involved in galactose and glucose metabolism. The varying clinical spectrum reflects the genetic complexity of this entity manifesting as acute neonatal toxicity syndrome, requiring prompt diagnosis and treatment, to more insidious clinical scenarios as observed in the subacute and chronic presentations. The current literature predominantly focuses on the long-standing sequelae of this disease. The purpose of this multicenter clinical report comprising 17 patients with galactosemia is to highlight the MR imaging patterns encompassing the whole spectrum of galactosemia, emphasizing the 3 main clinical subtypes: 1) acute neonatal presentation, with predominant white matter edema; 2) subacute clinical onset with a new finding called the "double cap sign"; and 3) a chronic phase of the disease with heterogeneous imaging findings. The knowledge of these different patterns together with MR spectroscopy and the clinical presentation may help in prioritizing galactosemia over other neonatal metabolic diseases and prevent possible complications.

Gestational Diabetes Mellitus: Clinical Characteristics and Perinatal Outcomes in a Multiethnic Population of North Italy

AIM

To evaluate clinical characteristics and perinatal outcomes in a heterogeneous population of Caucasians born in Italy and High Migration Pressure Countries (HMPC) women with GDM living in Piedmont, North Italy.

METHODS

We retrospectively analyzed data from 586 women referring to our unit (2015-2020). Epidemiological (age and country of origin) and clinical-metabolic features (height, weight, family history of DM, parity, previous history of GDM, OGTT results, and GDM treatment) were collected. The database of certificates of care at delivery was consulted in relation to neonatal/maternal complications (rates of caesarean sections, APGAR score, fetal malformations, and neonatal anthropometry).

RESULTS

43.2% of women came from HMPC; they were younger (p < 0.0001) and required insulin treatment more frequently than Caucasian women born in Italy (χ ² = 17.8, p=0.007). Higher fasting and 120-minute OGTT levels and gestational BMI increased the risk of insulin treatment (OGTT T0: OR = 1.04, CI 95% 1.016-1.060, p=0.005; OGTT T120: OR = 1.01, CI 95% 1.002-1.020, p=0.02; BMI: OR = 1.089, CI 95% 1.051-1.129, p < 0.0001). Moreover, two or more diagnostic OGTT glucose levels doubled the risk of insulin therapy (OR = 2.03, IC 95% 1.145-3.612, p=0.016). We did not find any association between ethnicities and neonatal/maternal complications.

CONCLUSIONS

In our multiethnic GDM population, the need for intensive care and insulin treatment is high in HPMC women although the frequency of adverse peripartum and newborn outcomes does not vary among ethnic groups. The need for insulin therapy should be related to different genetic backgrounds, dietary habits, and Nutrition Transition phenomena. Thus, nutritional intervention and insulin treatment need to be tailored.

Accuracy of Point-of-Care Ultrasound in Detecting Fractures in Children: A Validation Study

This study sought to compare point-of-care ultrasound (POCUS) and conventional X-rays for detecting fractures in children. This was a prospective, non-randomized, convenience-sample study conducted in five medical centers. It evaluated pediatric patients with trauma. POCUS and X-ray examination results were treated as dichotomous variables with fracture either present or absent. Descriptive statistics were calculated in addition to prevalence, sensitivity, specificity, positive predictive value and negative predictive value, including 95% confidence intervals (CIs). The Cohen κ coefficient was determined as a measurement of the level of agreement. A total of 554 examinations were performed with POCUS and X-ray. On physical examination, swelling, localized hematoma and functional limitation were found in 66.73%, 33.78% and 53.74% of participants, respectively. The most-studied areas were limbs and hands/feet (58.19% and 38.27%), whereas the thorax was less represented (3.54%). Sensitivity of POCUS was 91.67% (95% CI, 76.41-97.82%) for high-skill providers and 71.50 % (95% CI, 64.75-77.43%) for standard-skill providers. Specificity was 88.89% (95% CI, 73.00-96.34%) and 82.91% (95% CI, 77.82-87.06%) for high- and standard-skill providers, respectively. Positive predictive value was 89.19% (95% CI, 73.64-96.48%) and 75.90% (95% CI, 69.16-81.59%) for high- and standard-skill providers, respectively. Negative predictive value was 91.43% (95% CI, 75.81-97.76%) and 79.44% (95% CI, 74.21-83.87%) for high- and standard-skill providers, respectively. The Cohen κ coefficient showed very good agreement (0.81) for high-skill providers, but moderate agreement (0.54) for standard-skill providers. We noted good diagnostic accuracy of POCUS in evaluating fracture, with excellent sensitivity, specificity, and positive and negative predictive value for high-skill providers.

DTI parameters in neonates with hypoxic-ischemic encephalopathy after total body hypothermia

BACKGROUND AND PURPOSE

MR imaging provides means for discriminating different patterns of Hypoxic-ischemic encephalopathy (HIE) and may distinguish most severe cases from less severe but is unable to predict long-term outcome. Diffusion tensor imaging (DTI) offers information for a more complete characterization of HIE. The purpose of this study is to compare the modifications of DTI parameters in newborns one week and six months following total-body cooling to healthy controls.

METHODS

Forty-seven cooled newborns were studied with MRI, 20 underwent follow-up at 6 months. 12 healthy newborns and nine children at 6 months were enrolled as control groups (HC). Inferior Longitudinal Fasciculus (ILF), Corpus Callosum Fasciculus (CCF), Corticospinal Tract (CST), Optical Tract (OT), Optic Radiation (OR) were generated in all subjects. DTI parameters were evaluated in basal ganglia (BG), thalamus (TH) and tracks. Statistical analysis was performed with MANOVA.

RESULTS

In newborns HIE versus HC, there were significantly lower fractional anisotropy (FA) on OR and CST and higher axial diffusivity (AD), apparent diffusion coefficient (ADC) and radial diffusivity (RD) values on CST, BG and TH in HIE-N. At 6 months there were no significant grouping effects. The analysis showed a significant increase of FA, decrease of ADC, AD, RD after 6 months for HIE and HC.

CONCLUSIONS

We observed modifications of parameter values in HIE newborns vs HC; however normalization of values at 6 months suggests that changes of parameters cannot be considered early biomarkers for evaluation of therapeutic hypothermia in newborns with moderate HIE and normal conventional MRI.

A Pilot Prospective Study to Validate Point-of-Care Ultrasound in Comparison to X-Ray Examination in Detecting Fractures

Despite its limitations, conventional radiography is the method of choice for fracture evaluation in the emergency department. Only a few studies, moreover in limited populations, have evaluated the possible benefits of ultrasound (US), and especially of point-of-care ultrasound (POCUS), in the diagnosis of fractures. We sought to compare the accuracy of POCUS with that of conventional radiography in the diagnosis of bone fractures. This prospective study with a non-randomly allocated convenience sample was conducted at two academic medical centers. Four physicians, with focused training in musculoskeletal POCUS, evaluated consecutive patients with suspected orthopedic injury. US and X-ray examination results were treated as dichotomous variables with either fracture present or fracture absent. Descriptive statistics were calculated in addition to prevalence, sensitivity, specificity, positive predictive value and negative predictive value including 95% confidence intervals (CIs). Cohen's κ coefficient was determined as a measurement of the level of agreement. Four hundred sixty-nine patients (404 adult and 65 pediatric) ranging in age from 1-97 y were enrolled at two different hospitals. Seven hundred six examinations, both US and X-ray, were performed in 634 suspected fractures in adults (age ≥18 y) and 72 in children. On physical examination, swelling, localized hematoma and functional limitation were found in 64.61%, 34.97% and 53.52, respectively. The sensitivity of US examination was 93.89% (CI: 89.74%-96.49%) for all patients and 94.30% (CI: 89.77%-96.98%) and 91.67% (CI: 76.41%-97.82%) in adult and pediatric groups, respectively. Specificity was 94.13% (CI: 91.53-95.99), 94.56% (CI: 91.89-96.41) and 88.89% (CI: 73.00-96.38) for the whole group, adults and children, respectively. The positive predictive value was 88.48% (CI: 83.62%-92.08%), 88.35% (CI: 82.97%-92.24%) and 89.19% (CI: 73.64%-96.48%) for the whole group, adults and children, respectively. The negative predictive value was 96.98% (CI: 94.86%-98.27%), 97.43% (CI: 95.31%-98.64%) and 91.43% (CI: 75.81%-97.76%) in the three groups, respectively. Cohen's κ coefficient revealed high agreement of 0.87 for both the whole group and adult patients and 0.81 for pediatric patients. We found that POCUS has significant diagnostic accuracy in evaluating fracture compared with plain radiography, with excellent sensitivity, specificity and positive and negative predictive values.

Chiral Spin Texture in the Charge-Density-Wave Phase of the Correlated Metallic Pb/Si(111) Monolayer

We investigate the 1/3 monolayer α-Pb/Si(111) surface by scanning tunneling spectroscopy (STS) and fully relativistic first-principles calculations. We study both the high-temperature sqrt[3]×sqrt[3] and low-temperature 3×3 reconstructions and show that, in both phases, the spin-orbit interaction leads to an energy splitting as large as 25% of the valence-band bandwidth. Relativistic effects, electronic correlations, and Pb-substrate interaction cooperate to stabilize a correlated low-temperature paramagnetic phase with well-developed lower and upper Hubbard bands coexisting with 3×3 periodicity. By comparing the Fourier transform of STS conductance maps at the Fermi level with calculated quasiparticle interference from nonmagnetic impurities, we demonstrate the occurrence of two large hexagonal Fermi sheets with in-plane spin polarizations and opposite helicities.

Neuroimaging Changes in Menkes Disease, Part 2

This is the second part of a retrospective and review MR imaging study aiming to define the frequency rate, timing, imaging features, and evolution of gray matter changes in Menkes disease, a rare multisystem X-linked disorder of copper metabolism characterized by early, severe, and progressive neurologic involvement. According to our analysis, neurodegenerative changes and focal basal ganglia lesions already appear in the early phases of the disease. Subdural collections are less common than generally thought; however, their presence remains important because they might challenge the differential diagnosis with child abuse and might precipitate the clinical deterioration. Anecdotal findings in our large sample seem to provide interesting clues about the protean mechanisms of brain injury in this rare disease and further highlight the broad spectrum of MR imaging findings that might be expected while imaging a child with the suspicion of or a known diagnosis of Menkes disease.

Neuroimaging Changes in Menkes Disease, Part 1

Menkes disease is a rare multisystem X-linked disorder of copper metabolism. Despite an early, severe, and progressive neurologic involvement, our knowledge of brain involvement remains unsatisfactory. The first part of this retrospective and review MR imaging study aims to define the frequency rate, timing, imaging features, and evolution of intracranial vascular and white matter changes. According to our analysis, striking but also poorly evolutive vascular abnormalities characterize the very early phases of disease. After the first months, myelination delay becomes evident, often in association with protean focal white matter lesions, some of which reveal an age-specific brain vulnerability. In later phases of the disease, concomitant progressive neurodegeneration might hinder the myelination progression. The currently enriched knowledge of neuroradiologic finding evolution provides valuable clues for early diagnosis, identifies possible MR imaging biomarkers of new treatment efficacy, and improves our comprehension of possible mechanisms of brain injury in Menkes disease.

Photo-ignition process of multiwall carbon nanotubes and ferrocene by continuous wave Xe lamp illumination

This work aims to investigate and characterize the photo-ignition phenomenon of MWCNT/ferrocene mixtures by using a continuous wave (CW) xenon (Xe) light source, in order to find the power ignition threshold by employing a different type of light source as was used in previous research (i.e., pulsed Xe lamp). The experimental photo-ignition tests were carried out by varying the weight ratio of the used mixtures, luminous power, and wavelength range of the incident Xe light by using selective optical filters. For a better explanation of the photo-induced ignition process, the absorption spectra of MWCNT/ferrocene mixtures and ferrocene only were obtained. The experimental results show that the luminous power (related to the entire spectrum of the Xe lamp) needed to trigger the ignition of MWCNT/ferrocene mixtures decreases with increasing metal nanoparticles content according to previously published results when using a different type of light source (i.e., pulsed vs CW Xe light source). Furthermore, less light power is required to trigger photo-ignition when moving towards the ultraviolet (UV) region. This is in agreement with the measured absorption spectra, which present higher absorption values in the UV-vis region for both MWCNT/ferrocene mixtures and ferrocene only diluted in toluene. Finally, a chemo-physical interpretation of the ignition phenomenon is proposed whereby ferrocene photo-excitation, due to photon absorption, produces ferrocene itself in its excited form and is thus capable of promoting electron transfer to MWCNTs. In this way, the resulting radical species, FeCp2 ^+∙ and MWCNT^-, easily react with oxygen giving rise to the ignition of MWCNT/ferrocene samples.

Is the haematopoietic effect of testosterone mediated by erythropoietin? The results of a clinical trial in older men

The stimulatory effects of testosterone on erythropoiesis are very well known, but the mechanisms underlying the erythropoietic action of testosterone are still poorly understood, although erythropoietin has long been considered a potential mediator. A total of 108 healthy men >65 years old with serum testosterone concentration <475 ng/dL were recruited by direct mailings to alumni of the University of Pennsylvania and Temple University, and randomized to receive a 60-cm(2) testosterone or placebo patch for 36 months. Ninety-six subjects completed the trial. We used information and stored serum specimens from this trial to test the hypothesis that increasing testosterone increases haemoglobin by stimulating erythropoietin production. We used information of 67 men, 43 in the testosterone group and 24 in the placebo group who had banked specimens available for assays of testosterone, haemoglobin and erythropoietin at baseline and after 36 months. The original randomized clinical study was primarily designed to verify the effects of testosterone on bone mineral density. The primary outcome of this report was to investigate whether or not transdermal testosterone increases haemoglobin by increasing erythropoietin levels. The mean age ± SD of the 67 subjects at baseline was 71.8 ± 4.9 years. Testosterone replacement therapy for 36 months, as compared with placebo, induced a significant increase in haemoglobin (0.86 ± 0.31 g/dL, p = 0.01), but no change in erythropoietin levels (-0.24 ± 2.16 mIU/mL, p = 0.91). Included time-varying measure of erythropoietin did not significantly account for the effect of testosterone on haemoglobin (Treatment-by-time: β = 0.93, SE = 0.33, p = 0.01). No serious adverse effect was observed. Transdermal testosterone treatment of older men for 36 months significantly increased haemoglobin, but not erythropoietin levels. The haematopoietic effect of testosterone does not appear to be mediated by stimulation of erythropoietin production.

Phase i/ii trial of 5-Fluorouracil, leucovorin, Zidovudine and dipyridamole for patients with metastatic colorectal-cancer, renal-cell carcinoma and malignant-melanoma

We conducted a phase I/II trial of 5-fluorouracil (5-FU), calcium leucovorin (LV), zidovudine (AZT) and dipyridamole (DP), (FLAP) in patients with metastatic colorectal cancer, renal cell carcinoma and malignant melanoma. AZT and DP were given to enhance the biochemical modulation and antitumor activity of 5-FU and LV. All patients received 5-FU (370 mg/m(2) i.v. bolus day 0-4), LV (50 mg/m(2) p.o. every 4 h day 0-4) and DP (50 mg/m(2) p.o. every 6 h days 0-27). In the phase I portion of the study, AZT was dose escalated in cohorts of 5 patients each, from 50 mg p.o. every 6 h days 0-27 to the MTD of 200 mg p.o. every 6 h days 0-27. Thirty-three patients received 200 mg of AZT in the phase II portion of the trial. Eleven patients developed grade III and 5 patients developed grade IV leukopenia. Four patients developed grade III and 21 patients developed grade IV neutropenia, with six febrile neutropenic episodes. Six patients experienced grade III anemia and four grade III thrombocytopenia. Diarrhea or stomatitis of greater than or equal to grade III occurred in six and four patients, respectively. Fifty-eight percent (19 of 33) of patients required dose reductions of AZT for hematologic toxicity (13 of 19 in the first treatment cycle). At the 200 mg AZT dose level, there were two partial responses in nine colorectal cancer patients (22%), no objective responses in 14 patients with renal cell carcinoma or in 14 patients with melanoma. FLAP does not have significant activity in melanoma, renal cell carcinoma or 5-FU-treated colorectal cancer patients, although it may have activity in untreated colon cancer.

High twinning rate in Cândido Godói: a new role for p53 in human fertility

BACKGROUND

Cândido Godói (CG) is a small town in South Brazil, which has the highest prevalence of twin births in Brazil. Recently, a number of studies have shown that p53 plays an important role in reproduction through blastocyst implantation and intra utero embryo survival. Thus, gene polymorphisms in the p53 pathway were investigated in this population.

METHODS

Single nucleotide polymorphisms from five genes in the p53 pathway were investigated, as well as background characteristics of 42 mothers of twins (cases) and 101 mothers of singletons (controls), all residents from CG.

RESULTS

Mothers of twins have higher number of pregnancies and higher frequencies of P72 allele at TP53 and T allele at MDM4 genes compared with controls. Logistic regression shows that both TP53 and number of pregnancies maintained their association with twinning (P =0.004 and P =0.002, respectively), with TP53 having a higher odds ratio than number of pregnancies (2.73 versus 1.70, respectively). No interactive effect between TP53 and MDM4 (P =0.966) is observed. As expected, mothers of twins have three times more cases of cancer in their first-degree relatives than control mothers (P =0.011).

CONCLUSIONS

Our results suggest that the P72 allele of TP53 is a strong risk factor for twinning in CG, while the number of pregnancies and the T allele at MDM4 may represent weaker risk factors. These two alleles are associated with infertility, but the anti-apoptotic effect of low levels of p53 in general, and of the P72 allele in particular, may play a role after implantation, enhancing the chance for a double pregnancy to succeed to term.

Central nervous system tuberculosis in non-HIV-positive children: a single-center, 6 year experience

PURPOSE

The aim of this paper is to describe the imaging features of central nervous system (CNS) tuberculosis on computed tomography (CT) and magnetic resonance imaging (MRI) studies in non-HIV-positive children.

MATERIALS AND METHODS

A retrospective descriptive evaluation was conducted on imaging studies obtained from ten children admitted to our hospital over a 6-year period who fulfilled criteria for a diagnosis of CNS tuberculosis. Data were collected with regard to patients' clinical, laboratory and demographic characteristics, as well as results of radiological investigation.

RESULTS

We studied ten children, of whom five were boys and five were girls and whose mean age was 4 (range 7 months to 16) years. Neuroradiological findings on the first imaging study were basal meningeal enhancement (100%), hydrocephalus (70%), infarcts (90%), tuberculomas (40%) and cranial nerve involvement (20%). Follow-up studies revealed basal meningeal enhancement, hydrocephalus, and infarcts in all patients, tuberculomas in 70% and cranial nerve involvement in 50%. Only one patient showed a pattern of miliary tuberculosis.

CONCLUSIONS

CNS tuberculosis is still an important cause of childhood morbidity and mortality even in nonimmunosuppressed children. Because prompt diagnosis results in earlier treatment, it is crucial to be aware of tuberculous meningitis and its complications at imaging, especially because of the impact on patients' prognosis.

Advances in metal-based probes for MR molecular imaging applications

The role of MRI in the armory of diagnostic modalities for the medicine of the forthcoming years largely depends on how chemistry will provide advanced tools to meet the medical needs. This review aims at outlining the most innovative approaches that have been undertaken in the recent history of MRI contrast agents for tackling the challenges of sensitivity and specificity required by the new generation of contrast agents that should allow the visualization of pathological processes occurring on cellular and molecular scale (the so-called Molecular Imaging). Most of the classes of MRI agents clinically approved or currently under investigation in a preclinical phase exploit peculiar magnetic properties of metals. The conventional agents acting as T(1) or T(2)/T(2)* relaxation enhancers are primarily based on the paramagnetic or the superparamagnetic properties of Gd(III)-, Mn(II)- and iron oxides systems. Recently, there has been a renewed interest towards paramagnetic lanthanide complexes with an anisotropic electronic configuration thanks to their ability to induce strong effect on the resonance frequency of the spins dipolarly coupled with them. Such systems, formerly mainly used as shift reagents, have now attracted much attention in the emerging field of Chemical Exchange Saturation Transfer (CEST) MRI agents.

Dorsal brain stem syndrome: MR imaging location of brain stem tegmental lesions in neonates with oral motor dysfunction

The anatomic extent of brain stem damage may provide information about clinical outcome and prognosis in children with hypoxic-ischemic encephalopathy and oral motor dysfunction. The aim of this study was to retrospectively characterize the location and extent of brain stem lesions in children with oral motor dysfunction. From January 2005 to August 2009, 43 infants hospitalized at our institution were included in the study because of a history of hypoxic-ischemic events. Of this group, 14 patients showed oral motor dysfunction and brain stem tegmental lesions detected at MR imaging. MR imaging showed hypoxic-ischemic lesions in supra- and infratentorial areas. Six of 14 patients revealed only infratentorial lesions. Focal symmetric lesions of the tegmental brain stem were always present. The lesions appeared hyperintense on T2-weighted images and hypointense on IR images. We found a strong association (P < .0001) between oral motor dysfunction and infratentorial lesions on MR imaging. Oral motor dysfunction was associated with brain stem tegmental lesions in posthypoxic-ischemic infants. The MR imaging examination should be directed to the brain stem, especially when a condition of prolonged gavage feeding is necessary in infants.

Parapharyngeal neuroglial heterotopia in Pierre Robin sequence: MR imaging findings

Heterotopic neuroglial tissue is a rare lesion, occurring more frequently in the nasal cavities. Other rare locations are the orbit, the scalp, the palate, the pharynx, the parapharyngeal space and the lungs. They are usually detected occasionally because they are often asymptomatic, but sometimes they might present with dyspnoea, feeding difficulty, snorting and nasal flaring. Respiratory symptoms occur when heterotopic neuroglial tissue is located in the parapharyngeal space. We report a case of an infant affected by Pierre Robin sequence (PRS) who was admitted to our Institution for a worsening respiratory distress that was not explainable only by PRS.

HIL Tuning of UAV for Exploration of Risky Environments

In this paper the latest results of an HIL architecture, optimized to develop and test UAV platforms are presented. This architecture has been used to realize the different devices involved in the navigation and stability control of the Volcan UAV, a plane designed to operate in volcanic environments.

The proposed architecture is strongly modular and flexible and allows the development of avionic hardware and software, testing and tuning the involved algorithms with non-destructive trials. A flight simulator (X-Plane) with a suitable plane model and plug-in, has been adopted to simulate the UAV dynamics. The flight simulator, interfaced with the real electronic boards, allows an easy tuning of all the control parameters and data collecting for test and validation.

The effectiveness of adopted methodology was confirmed by several flight tests performed subsequently by using the designed avionic modules on the real UAV.

Lifestyle, family history and progression of hypertension

BACKGROUND

Unhealthy lifestyle practices are risk factors for future hypertension.

OBJECTIVES

The aim of this study was to investigate the association between lifestyle changes over a 6-year period and the risk of developing sustained hypertension in a cohort of young hypertensive individuals, and to identify the predictors of lifestyle impairment over time.

METHODS

Seven-hundred and eighty never-treated hypertensive HARVEST participants, 18-45 years old, were studied.

RESULTS

Only modest mean behavioral changes were observed during follow-up. This, however, was the net result of many participants improving and others worsening their lifestyle. Participants with a family history of hypertension (FH+, n = 459) had more undesirable lifestyles (P = 0.004) and higher clinic and ambulatory blood pressures (P = 0.03) at baseline than participants without a family history of hypertension (FH-). During the 6-year follow-up, FH- individuals strikingly worsened their lifestyle while FH+ participants exhibited impressive improvements (P < 0.00001). Other predictors of lifestyle impairment were male gender (P = 0.003) and age (P = 0.02). Adoption of an unfavorable lifestyle was accompanied by an increased risk of developing sustained hypertension (P = 0.04). Initiation of drug therapy for hypertension was significantly higher among FH- than FH+ individuals (53 versus 45%, respectively; P = 0.045).

CONCLUSIONS

'Lower risk' FH- stage 1 hypertensive individuals may initially be at higher risk of developing more severe hypertension in comparison with their FH+ counterparts. This increased risk may be attributed to worsening of their lifestyle profiles over time. Healthy lifestyles should be emphasized to all hypertensive individuals including patients with favorable lifestyle profiles.

Real time blood flow velocity monitoring in the microcirculation

A real-time monitoring system based on the dual slit methodology for the characterization of the red blood cell velocity at the level of microcirculation has been developed. The analog photometric signals are acquired and processed using a hybrid hardware-software system that exploits a A/D conversion and an optimized correlation algorithm on an embedded system. It is implemented exploiting the resources of a general purpose board capable to extract the useful information from the noisy photometric signals, to process them, to show and save the results and, therefore, to make the experiments reproducible. Two different approaches to the crosscorrelation algorithm have been tested and their performances have been compared to each. The system has been tested in in vivo experiments on anaesthetized hamsters. Several microvessels have been observed and the results have been compared to the output of an analog crosscorrelator to verify their coherence.

Effect of body weight loss on blood pressure after 6 years of follow-up in stage 1 hypertension

BACKGROUND

Although it is known that weight reduction reduces blood pressure (BP) in overweight patients, the optimal body weight (BW) loss in terms of BP response is not yet established. We evaluated the relationship between decrease in BW and BP over time in 796 stage 1 hypertensives.

METHODS

The 166 subjects who lost BW were divided into four groups according to percent of BW loss at the end of a 74-month follow-up (G1, >2% to 5%, G2, >5% to 9%, G3, >9% to 13%, and G4, >13%) and were compared to the 219 subjects without changes in BW (G0, -2% to +2%). The BW increased (>2%) in the remaining 411 subjects.

RESULTS

Among subjects with BW loss there was a progressive decrease in final systolic BP associated with BW loss category up to G3 (P = .007), therefore at the end of follow-up G3 had systolic BP 6.2 mm Hg lower than G0 (P = .06). However, among G3 and G4 subjects systolic BP decrease was almost identical (-6.2 nu -5.7 mm Hg, respectively, P = not significant). Similar results were obtained for diastolic BP, which declined up to G3 (P = .013). G3 had final diastolic BP 3.6 mm Hg lower than G0 (P = .037), whereas change in diastolic BP in G4 subjects was similar to that in G0 (-0.9 nu +0.1 mm Hg, respectively, P = not significant). Similar results were obtained in the group with body mass index (BMI) >27 kg/m(2).

CONCLUSIONS

Our results indicate that in stage 1 hypertensives followed for more than 6 years the dose-response relationship between BW loss and decrease in BP is not linear irrespective of initial BW. The BW loss >13% of initial weight did not elicit additional BP decrease.

Impaired arterial elasticity in young patients with white-coat hypertension

BACKGROUND

Conflict still exists over whether patients with white-coat hypertension are at increased risk of developing target organ damage compared with normotensive individuals.

METHODS

We studied vascular distensibility in 117 young-to-middle age patients with white-coat hypertension, 174 patients with sustained hypertension, and 51 normotensive controls. To obtain a measure of compliance, a model was used that divides the total systemic compliance into large artery (C1) and small artery (C2) compliance. With this aim, radial arterial pulse waves were recorded with a tonometer sensor array by means of an HDI CR2000 device (Eagan, Minnesota, USA). Moreover, pulse wave velocity and the augmentation index were measured using the Specaway DAT system (St Pauls, Sydney, Australia).

RESULTS

Patients with sustained hypertension had a greater body mass index than patients with white-coat hypertension (P=0.04) or the normotensive individuals (P=0.01). C1 and C2 were decreased in the two hypertensive groups as compared with those in the normotensive group (P=0.0002 and 0.03, respectively, versus sustained hypertension; P=0.00007 and 0.0004, respectively, versus white-coat hypertension). Pulse wave velocity and aortic augmentation index were increased in the white-coat hypertension patients compared with the normotensive individuals (P=0.02 and 0.004, respectively). Aortic augmentation index (P=0.008) but not pulse wave velocity was increased in the sustained hypertensive patients compared with that in the normotensive individuals. All indexes of arterial distensibility were similar in the two hypertensive groups.

CONCLUSIONS

Indexes of arterial distensibility are impaired in the white-coat hypertensive group and similar to those in the sustained hypertensive group, indicating that early changes in the arterial wall can occur in white-coat hypertension. This may account for the higher risk of stroke that has been described in this condition.

Fluconazole prophylaxis in extremely low birth weight infants: association with cholestasis

BACKGROUND

Extremely low birth weight (ELBW) infants are at increased risk for invasive candidiasis and associated morbidity and mortality. The use of fluconazole prophylaxis in this population has raised a benefit versus risk concern among clinicians.

OBJECTIVES

To evaluate the effectiveness and safety of fluconazole prophylaxis in ELBW infants.

STUDY DESIGN

ELBW infants (BW<or=1,000 g) born during the pre-prophylaxis era (PPE, January 1998-February 2002) were compared with prophylaxis era (PE, March 2002-September 2005). Infants born during PE received fluconazole prophylaxis for 6 weeks, as long as they had intravenous access. Demographic and clinical data were collected. The two groups were compared for baseline demographics, risk factors for candidiasis, the incidence of invasive candidiasis, liver enzymes, alkaline phosphatase, and bilirubin (total and direct).

RESULTS

Nine out of 137 infants (6.6%) developed invasive candidiasis during PPE compared to none of 140 (0%) during PE (P=0.006). During PE, 60/140 (42.9%) infants developed conjugated hyperbilirubinemia compared to 12/137 (8.8%) during PPE (P<0.001).

CONCLUSION

Although a fluconazole prophylaxis regimen for ELBW infants was effective in preventing invasive candidiasis, an increase in the incidence of conjugated hyperbilirubinemia was observed. Further studies are needed to evaluate the safety of fluconazole prophylaxis in this population.

Evolution of blood pressure and cholesterol in stage 1 hypertension: role of autonomic nervous system activity

OBJECTIVE

Controversy remains concerning the pathogenetic mechanisms for the relationship between sympathetic activity, hypertension and lipid abnormalities. We tested the hypothesis that a condition characterized by sympathetic predominance may affect the evolution of blood pressure and lipids in the early stage of hypertension.

METHODS

We prospectively studied 163 young stage 1 hypertensive individuals and 28 normotensive control individuals. The hypertensive subjects were divided by cluster analysis into two groups according to low frequency and high frequency components of heart rate variability. Large artery and small artery compliance was assessed at the end of the follow-up.

RESULTS

Fifty-nine subjects showed reduced total power and signs of sympathetic predominance in the resting condition, on standing and during mental stress (group 1). At baseline, they had similar blood pressure and metabolic data to the rest of the group (n = 104, group 2) and a greater white-coat effect (P = 0.03). During a 6-year follow-up, 23.7% of group 1 subjects versus 9.6% of group 2 subjects developed sustained hypertension requiring antihypertensive treatment (P = 0.02). In group 1 subjects, there was also a greater increase in total cholesterol (P = 0.01) than in group 2. In addition, at the end of follow-up group 1 subjects had impaired large artery compliance (P < 0.001 versus group 2).

CONCLUSIONS

These data indicate that a condition characterized by sympathetic predominance may favour the development of sustained hypertension and hypercholesterolemia early in life, and lead to increased susceptibility to vascular complications. They further indicate that the increased white-coat effect is not an innocent phenomenon.

Masked hypertension in adults

A body of evidence indicates that masked hypertension is a significant predictor of cardiovascular disease, but how to identify these patients is still a matter of dispute. Data obtained in several cross-sectional studies have demonstrated that masked hypertension is associated with increased left ventricular mass index and carotid intima-media thickness, and impaired large artery distensibility. Furthermore, in longitudinal studies, masked hypertension was a strong predictor of cardiovascular morbidity and mortality. Several factors that can selectively raise ambulatory blood pressure increase the likelihood of having masked hypertension. These include younger age, smoking, alcohol use, contraceptive use in women, sedentary habits and central obesity. In addition, masked hypertension is more common in individuals with high-normal clinic blood pressure or transiently elevated blood pressure. Increased reactivity to daily life stressors and behavioural factors are other important predictors of masked hypertension. In clinical practice, masked hypertension should be searched for in individuals who are more likely to have this condition or are at increased risk of cardiovascular events including those with coronary, cerebrovascular or kidney disease, patients with diabetes and individuals with a high cardiovascular risk profile. To determine whether the use of ambulatory blood pressure monitoring is cost-effective in these individuals, further research is needed.

MRI and 1H-MRS findings in early-onset cobalamin C/D defect

OBJECT

Cobalamin C/D defect is an inborn error of cobalamin metabolism causing methylmalonic aciduria and homocystinuria. The early-onset form is characterized by severe neurological impairment. The aim of this study was to evaluate and monitor brain damage in early-onset cbl-C/D defect by conventional MRI and to assess the additional value of 1H-MRS.

METHODS

We retrospectively examined serial MRI studies of 7 patients, performed on a 1.5 T system. Four patients had the first evaluation within the first 4 months of life and three later. The imaging protocol included spin-echo T1-weighted, T2-weighted, IR, and FLAIR. Five patients underwent 1H-MRS, using chemical shift imaging (CSI) in three patients and single voxel spectroscopy (SVS) in two.

RESULTS

Three of the patients studied early showed tetraventricular hydrocephalus and diffuse swelling of supratentorial white matter with involvement of the "U" fibres. Two showed patchy cavitating lesions in the basal ganglia. White matter changes became evident at a later stage. In three cases 1H-MRS showed an abnormal peak of lactate in the basal ganglia or in the periventricular white matter.

CONCLUSIONS

Our study shows severe heterogeneous brain MR abnormalities in cbl-C/D defect. We observed unusual basal ganglia lesions in 30 % of our cases and also found a high incidence of hydrocephalus and supratentorial white matter abnormalities.

A multi-functional, portable device with wireless transmission for home monitoring of children with a learning disability

A portable monitoring device was developed to assist in the management of children with a learning disability. The device was designed for continuous home monitoring of blood oxygen saturation, heart and respiration rates, and patient activity. It could be worn on a belt, while the patient continued normal activities. Data were stored on a multimedia card and automatically transmitted to a PC at prescribed intervals via a Bluetooth wireless link. From the PC the data were transmitted to a Web server, where the information was made available to the staff involved in the patient's care. Preliminary clinical studies were performed with nine patients (four with Down's syndrome, three with cerebral palsy and two with mental retardation). Patients and families considered the device easy to use and to wear. The monitoring device identified events of possible clinical interest. Although it was designed for monitoring children with a learning disability, it may also be useful with other groups, such as elderly people.

Microalbuminuria, renal function and development of sustained hypertension

OBJECTIVE

Microalbuminuria (MA) is a marker of adverse outcome in hypertension. The aim of this study was to investigate the association of MA with cardiovascular risk factors and glomerular hyperfiltration in the early stage of hypertension and to assess its predictive value for the development of sustained hypertension requiring antihypertensive treatment.

DESIGN AND PARTICIPANTS

We studied 1041 young stage 1 hypertensive subjects. Study variables were 24-h ambulatory blood pressure and heart rate, anthropometric measures, metabolic variables, creatinine clearance and lifestyle factors analyzed as a function of ascending urinary albumin measured from 24-h collections. Subjects were followed until they developed sustained hypertension and were eligible for antihypertensive medication according to current guidelines.

SETTING

Seventeen outpatient clinics in Italy.

RESULTS

Eighty-five percent of the subjects were normoalbuminuric, 9% had borderline MA, and 6% had overt MA. No between-group differences were found for age, body mass index, heart rate, lifestyle factors and biochemistry in both genders. Creatinine clearance was greater in the subjects with overt MA and borderline MA than in the normoalbuminuric subjects (P = 0.003 and 0.011, respectively). In a two-way ANCOVA, microalbuminuric subjects both with hyperfiltration (P < 0.001) and with normal filtration (P = 0.04) had higher 24-h systolic blood pressure than subjects with normoalbuminuria and normal filtration. In a Cox analysis, neither MA nor hyperfiltration were significant predictors of development of sustained hypertension.

CONCLUSION

MA is not associated with an adverse metabolic risk profile in the early stage of hypertension. MA is associated with greater hemodynamic load and with glomerular hyperfiltration in this clinical setting, but does not help in predicting those subjects destined to develop sustained hypertension requiring antihypertensive therapy.

Prevalence and Clinical Significance of Isolated Ambulatory Hypertension in Young Subjects Screened for Stage 1 Hypertension

Little is known about the clinical significance of isolated ambulatory hypertension, a condition characterized by low office but elevated ambulatory blood pressure. This study aimed to investigate the prevalence and the predictive value of isolated ambulatory hypertension diagnosed after 3 months of observation for the development of sustained hypertension within a cohort of 871 never-treated stage-1 hypertensive subjects. The study end point was progression to more severe hypertension and need of antihypertensive medication. In 244 subjects (28%), clinic blood pressure declined to <140/90 mm Hg after 3 months. Of these, 124 (14.2% of total) had low clinic and ambulatory blood pressures after 3 months (nonhypertensive subjects), whereas 120 subjects (13.8% of total) showed low clinic but elevated ambulatory blood pressure (isolated ambulatory hypertension). During the 6 years of observation, the number of end points based on multiple clinic blood pressure readings progressively increased from the nonhypertensive subjects (19%) to the subjects with isolated ambulatory hypertension (35%) and to the subjects with high clinic and high ambulatory blood pressures (65%, P<0.0001). In an adjusted proportional hazard model, isolated ambulatory hypertension status was associated with a 2.2 (P=0.02) increase in the risk of reaching the end point in comparison with the nonhypertensive subjects. Final ambulatory systolic blood pressure was also higher in the former than the latter (P=0.03). Our results indicate that among subjects screened for stage 1 hypertension, individuals with isolated ambulatory hypertension after 3 months of observation have increased risk of developing sustained hypertension in later life compared with subjects in whom both clinic and ambulatory blood pressures are normal.

Wrist blood pressure overestimates blood pressure measured at the upper arm

OBJECTIVE

Whether blood pressure (BP) measured at the wrist differs from blood pressure measured at the arm is not well known. The aim of this study was to compare the BP readings obtained at the arm with those obtained at the forearm and to assess whether the wrist-arm discrepancies were related to subjects' clinical characteristics.

METHODS

We measured blood pressure at the forearm and at the upper arm in 85 subjects using conventional sphygmomanometry. Wrist-arm blood pressure discrepancies were assessed in relation to gender, age, body mass index, skin-fold thickness, arm size, blood pressure level, and arterial compliance measured with the HDI/Pulsewave CR-2000.

RESULTS

Blood pressure measured at the wrist consistently overestimated blood pressure taken at the arm with a mean (+/-SD) discrepancy of 8.2 +/- 9.7/9.2 +/- 6.4 mmHg. The systolic blood pressure differences were greater in men than in women (p=0.006) and, among the men, varied according to arm adiposity (positive association, p=0.01). In men, diastolic blood pressure differences correlated with diastolic blood pressure level (negative association, p=0.01). Among the women, only age (p=0.04) was a significant positive independent predictor of the wrist-arm diastolic BP differences.

CONCLUSIONS

These results indicate that forearm blood pressure measurement markedly overestimates upper arm blood pressure and that the between-site difference may vary from subject to subject. Wrist blood pressure measurement is not a valid alternative to traditional measurement at the arm and its use should be discouraged.

Assessment of the fetal nasal bone at 11-14 weeks of gestation by three-dimensional ultrasound

OBJECTIVE

To evaluate the benefit of three-dimensional (3D) ultrasound in the examination of the fetal nasal bone at 11-14 weeks of gestation.

METHOD

We examined the fetal nasal bone in 120 stored volumes acquired transabdominally with a 3D scanner from singleton pregnancies at 11-14 weeks of gestation. The volume acquisition had been performed following conventional ultrasound examination that had demonstrated presence of the fetal nasal bone. The volumes were obtained with two-dimensional (2D) start images in transverse, coronal mid-sagittal, parasagittal and oblique longitudinal sections of the fetal head.

RESULTS

In the transverse and coronal sections, a satisfactory image demonstrating presence of the nasal bone was achieved in only three and one, respectively, of the 20 volumes that we obtained. In mid-sagittal sections, the nasal bone was always visible when the angle was within a range of 30-60 degrees, without the need for sectional image analysis. None of the images with an angle >60 degrees or <30 degrees was satisfactory. In the parasagittal sections with the fetal profile at 45 degrees, a good-quality image of the nasal bone was possible in all cases that were examined, irrespective of the distance from the mid-sagittal plane. In the oblique longitudinal sections with the fetal profile at 45 degrees, there were 10 volumes where the 2D start section was at 0-25 degrees from the midline and in all these cases the nasal bone was successfully visualized. In contrast, only 5/20 cases where the 2D start section was at 25-90 degrees from the midline provided a satisfactory image demonstrating the nasal bone. In 5/10 volumes obtained with the fetus facing downwards the nasal bone was visible in both the 2D and 3D images.

CONCLUSION

In a 3D volume the extent to which the nasal bone can be demonstrated to be present in a given reconstructed section is entirely dependent on obtaining a good initial 2D view.

Femur and humerus length in trisomy 21 fetuses at 11-14 weeks of gestation

OBJECTIVE

To determine the value of measuring fetal femur and humerus length at 11-14 weeks of gestation in screening for chromosomal defects.

METHODS

Femur and humerus lengths were measured using transabdominal ultrasound in 1018 fetuses immediately before chorionic villus sampling for karyotyping at 11-14 weeks of gestation. In the group of chromosomally normal fetuses, regression analysis was used to determine the association between long bone length and crown-rump length (CRL). Femur and humerus lengths in fetuses with trisomy 21 were compared with those of normal fetuses.

RESULTS

The median gestation was 12 (range, 11-14) weeks. The karyotype was normal in 920 fetuses and abnormal in 98, including 65 cases of trisomy 21. In the chromosomally normal group the fetal femur and humerus lengths increased significantly with CRL (femur length = - 6.330 + 0.215 x CRL in mm, r = 0.874, P < 0.0001; humerus length = - 6.240 + 0.220 x CRL in mm, r = 0.871, P < 0.0001). In the Bland-Altman plot the mean difference between paired measurements of femur length was 0.21 mm (95% limits of agreement - 0.52 to 0.48 mm) and of humerus length was 0.23 mm (95% limits of agreement - 0.57 to 0.55 mm). In the trisomy 21 fetuses the median femur and humerus lengths were significantly below the appropriate normal mean for CRL by 0.4 and 0.3 mm, respectively (P = 0.002), but they were below the respective 5th centile of the normal range in only six (9.2%) and three (4.6%) of the cases, respectively.

CONCLUSION

At 11-14 weeks of gestation the femur and humerus lengths in trisomy 21 fetuses are significantly reduced but the degree of deviation from normal is too small for these measurements to be useful in screening for trisomy 21.

Physical activity and angiotensin-converting enzyme gene polymorphism in mild hypertensives

It has been suggested that the insertion(I) allele of the I/deletion(D) polymorphism of the angiotensin converting enzyme (ACE) gene is associated with endurance exercise and increased physical conditioning in response to this type of exercise. To investigate the association between the ACE I/D polymorphism and physical activity status in 355 never treated, stage I hypertensives (265 men, 90 women, mean age: 33 +/- 9 years), in whom power exercise is contraindicated, participants of the HARVEST study. Physical activity was assessed using a standardized questionnaire. BMI and age did not vary among genotypes. None of active subjects performed power oriented exercises. ACE I/D frequencies (II-18%, ID-55%, DD-27%) were in Hardy-Weinberg equilibrium. Sedentary lifestyle was more common among DD than II hypertensives (76% in DD, and 48% in II, Chi(2) = 13.9, P = 0.001). In stepwise MANOVA using age, marital status, profession, sex, and ACE genotype as predictors of physical activity, marital status (F = 24.4, P < 0.0001) and ACE genotype (F = 16.03, P < 0.0001) contributed to more than 50% of the variance in physical activity status of the population. Our results suggest that the ACE I/D polymorphism may be a specific genetic factor associated with physical activity levels in free-living borderline and mild hypertensive subjects.