Application of a SARS-CoV-2 Antigen Rapid Immunoassay Based on Active Microfluidic Technology in a Setting of Children and Young Adults

To carry out effective and quick identification of SARS-CoV-2 from nasopharyngeal swabs and contain outbreaks, reliable and rapid tools are needed. Herein, we compared a rapid antigen test based on active microfluidic technology to an RT-qPCR assay in pediatric and young adult patients admitted to the Pediatric Emergency Unit of a Children's Hospital. Nasopharyngeal swabs collected from patients with suspected COVID-19 disease and from those without COVID-19 related symptoms, but requiring hospitalization, were performed with both antigen test and RT-qPCR assays. We included 375 patients with a median age of 5 years in the study, with an estimated overall prevalence of 7.2%. Overall, we observed a specificity of 97.4% (95% CI: 94.9-98.7) and a sensitivity of 66.6% (95% CI: 46.0-82.7) with a positive likelihood ratio (LR+) of 25.8 (95% CI: 12.8-51.8). In the subgroup of symptomatic patients, the specificity and the sensitivity were 95.2% (95% CI: 89.4-98.0) and 80.0% (95% CI: 44.2-96.5) respectively; LR+ was 16.6 (95% CI: 7.19-38.6). In the asymptomatic subset, the performance showed a specificity of 98.7% (95% CI: 95.8-99.7), a sensitivity of 58.8% (95% CI: 33.5-80.6), and an LR+ of 43.7 (95% CI: 13.3-144.0). Compared to RT-qPCR, the new microfluidic-based antigen test showed higher specificity (>95%) in the pediatric population, thus representing a suitable point-of-care testing (POCT) in a clinical setting with low prevalence of COVID-19.

Bayesian estimation of post-test probability of Candida glabrata fungemia by means of serum creatinine

Fungemia is a life-threatening condition associated with high mortality; the most frequently isolated genus is Candida. Candida glabrata is of particular concern because of its increasing resistance to azoles. We evaluated common lab tests accessible by almost all healthcare professionals to estimate the post-test probability of recovery of C. glabrata from a blood culture collected by venipuncture, positive for fungi identified by microscopic examination. Patients with blood cultures positive for C. glabrata had significantly higher median values of serum creatinine (P=0.006), and a value of ≥1.45 mg/dL was the best cut-off in discriminating C. glabrata from other Candida spp., with 0.67 [95% Confidence Interval (CI): 0.49-0.85] sensitivity and 0.75 (95% CI: 0.66-0.84) specificity; Youden's J statistic: 0.42. The receiver operator characteristic curve analysis showed an area under the curve of 0.718 (95% CI: 0.603-0.833); P=0.001. Therefore, given a pre-test probability of 24% and applying the Bayes' theorem, the post-test probability of C. glabrata fungemia with creatinine values ≥1.45 mg/dL increased to 45.8%. In conclusion, we showed how the probability of recovery of C. glabrata from blood cultures collected by venipuncture and positive for fungi can be better estimated using concurrent creatinine values.

POS1543-HPR Joining Telemedicine Services in Rheumatology: the Role Played by Personalized Experience From Patients’ Perspective

Background

With the beginning of the Covid-19 pandemic, many hospital departments worldwide, including rheumatology ones, were forced to implement telemedicine strategies. Telemedicine revealed to be an umbrella term, with various practical implementations and different degrees of preparedness1. Some practitioners were already familiar with telemedicine, as in the case of the Rheumatology Unit of ASST Niguarda Hospital in Milan (Italy), where telemedicine projects have been implemented for more than a decade with structured design and organized processes. Moreover, patients in Niguarda have experimented telemedicine with personalized mixes of channels, including e-mails and phone calls, Patient Reported Outcomes questionnaires, and home delivery of drugs. This represents a paradigmatic case study that enables us to deepen essential questions on the success of telemedicine.

Objectives

Given that the last decision on joining telemedicine rests with patients2, we decided to adopt their perspective. We deepened three main aspects: i) the benefits perceived, ii) the willingness to enrol in future projects, iii) the preference on the service-mix, i.e., on-distance contacts rather than in-person visits. Most importantly, we investigated differences in the three areas among all patients based on the type of personalized experience had.

Methods

We conducted a survey from November 2021 to January 2022, enrolling randomly outpatients who attended the rheumatology unit for any reason. The survey originated from well-known surveys, such as the TeleHealth Usability Questionnaire3 and the Intention to use telehealth services4. However, we decided to overcome the usual separation that makes surveys addressed either to users or no users of telemedicine. Our survey comprised an introductory set of questions related to personal, social, clinical and ICT skills information, followed by the central part on telemedicine, which explored the three areas mentioned: benefits, adherence, preferences on service-mix. For this part, questions were the same for all patients apart from the tense used, being conditional tense for no-users and past tense for users. All the answers were analysed with descriptive statistics and regression models.

Results

A complete response was given by 400 patients: 71% were female, 59% were 40-64 years old, 53% of them declared to work, and the diseases most represented were Rheumatoid Arthritis (36%) and Osteoporosis/arthrosis (21%).

The descriptive statistics revealed interesting differences between users and no users, e.g., the desire to participate in future projects was stated by 95% of users, 81% of no users. These results were confirmed by multivariate logistic regression models that controlled for the influencing patients’ characteristics (such as being old or a frequent hospital attender).

It emerged that no-users imagined wide-ranging benefits. As for the willingness to participate to future telehealth projects, even if personal characteristics showed an impact (e.g., being a worker increased the probability to adhere), other things being equal, having had a more intense experience of telemedicine increased the odds of accepting by 3.1 times (95% C.I. 1.04-9.25), compared to no users. Furthermore, the more telemedicine was experienced, the higher the willingness to substitute in-person with online contacts.

Conclusion

Our study contributes to enlighten the crucial role played by the telemedicine experience in determining patients’ preferences. On one side, users appeared more aware of the realistic benefits to be expected from telemedicine. On the other side, it seemed that the more telemedicine was experienced, the higher the willingness to adhere to future projects and to increase on-distance contacts.

References

[1]Hashiguchi T.C.O. 2020. Bringing health care to the patient: An overview of the use of telemedicine in OECD countries.

[2]Eze ND et al. 2020 PloS one

[3]ParmantoB, et al. 2016 International journal of telerehabilitation

[4]Ghaddar S et al. 2020 Journal of Medical Internet Research

Acknowledgements

This study would not have been possible without the support of the whole staff of the Rheumatology unit who contributed to the distribution of the survey

Disclosure of Interests

Elisabetta Listorti: None declared, Lucia Ferrara: None declared, Antonella Adinolfi Speakers bureau: Janssen, BMS, Maria Chiara Gerardi: None declared, Nicola Ughi Speakers bureau: ROCHE, PFIZER, ALFASIGMA, ABBVIE, JANSSEN, GALAPAGOS, BRISTOL MYERS SQUIBB, Valeria Tozzi: None declared, oscar massimiliano epis: None declared

Evaluating the risk of ovarian cancer before surgery using the ADNEX model: a multicentre external validation study

BACKGROUND

The International Ovarian Tumour Analysis (IOTA) group have developed the ADNEX (The Assessment of Different NEoplasias in the adneXa) model to predict the risk that an ovarian mass is benign, borderline, stage I, stages II-IV or metastatic. We aimed to externally validate the ADNEX model in the hands of examiners with varied training and experience.

METHODS

This was a multicentre cross-sectional cohort study for diagnostic accuracy. Patients were recruited from three cancer centres in Europe. Patients who underwent transvaginal ultrasonography and had a histological diagnosis of surgically removed tissue were included. The diagnostic performance of the ADNEX model with and without the use of CA125 as a predictor was calculated.

RESULTS

Data from 610 women were analysed. The overall prevalence of malignancy was 30%. The area under the receiver operator curve (AUC) for the ADNEX diagnostic performance to differentiate between benign and malignant masses was 0.937 (95% CI: 0.915-0.954) when CA125 was included, and 0.925 (95% CI: 0.902-0.943) when CA125 was excluded. The calibration plots suggest good correspondence between the total predicted risk of malignancy and the observed proportion of malignancies. The model showed good discrimination between the different subtypes.

CONCLUSIONS

The performance of the ADNEX model retains its performance on external validation in the hands of ultrasound examiners with varied training and experience.

Accuracy of ultrasonography performed by examiners with varied training and experience in predicting specific pathology of adnexal masses

OBJECTIVES

To assess the diagnostic performance of subjective assessment by Level II ultrasound examiners in predicting the specific histology of adnexal masses.

METHODS

The women included in this prospective multicenter cross-sectional study were older than 16 years of age and had at least one adnexal mass. They underwent transvaginal sonography (TVS) performed by Level II examiners, all of whom were familiar with the International Ovarian Tumor Analysis (IOTA) group definitions of ultrasound features of ovarian masses. The final outcome was histology. Specific diagnoses were categorized into 16 groups. Agreement between subjective assessment and final histology was measured using unweighted kappa coefficients. Sensitivities and specificities were obtained for subjective assessment.

RESULTS

Of the 1279 women who underwent TVS, 313 were included in the final analysis. Overall agreement (16 × 16 table) between subjective assessment and histology was moderate, with a Cohen's kappa coefficient of 0.59 (95% CI, 0.53-0.65). The specificity of subjective assessment ranged between 91% and 100% for all histological subgroups. Highest sensitivities were achieved in the diagnosis of simple cysts (100% (95% CI, 61-100%)), hydrosalpinges (100% (95% CI, 34-100%)), mature teratomas (88% (95% CI, 74-96%)), endometriomas (75% (95% CI, 61-85%)), ovarian fibromas (88% (95% CI, 47-100%)), tubo-ovarian abscesses (88% (95% CI, 47-100%)) and serous cystadenocarcinomas (82% (95% CI, 66-93%)). Serous cystadenomas were misdiagnosed most commonly (40.5%). The sensitivity of subjective assessment in diagnosing adnexal torsion was 54% (95% CI, 25-81%); the 17 confirmed and/or suspected cases of adnexal torsion were not included in the 313 cases examined and analyzed for diagnostic performance.

CONCLUSION

Overall, subjective assessment by Level II examiners was good for the detection of simple cysts, endometriomas, mature teratomas, hydrosalpinges, fibroma, tubo-ovarian abscess and serous cystadenocarcinomas.

Automated characterisation of ultrasound images of ovarian tumours: the diagnostic accuracy of a support vector machine and image processing with a local binary pattern operator

INTRODUCTION

Preoperative characterisation of ovarian masses into benign or malignant is of paramount importance to optimise patient management.

OBJECTIVES

In this study, we developed and validated a computerised model to characterise ovarian masses as benign or malignant.

MATERIALS AND METHODS

Transvaginal 2D B mode static ultrasound images of 187 ovarian masses with known histological diagnosis were included. Images were first pre-processed and enhanced, and Local Binary Pattern Histograms were then extracted from 2 × 2 blocks of each image. A Support Vector Machine (SVM) was trained using stratified cross validation with randomised sampling. The process was repeated 15 times and in each round 100 images were randomly selected.

RESULTS

The SVM classified the original non-treated static images as benign or malignant masses with an average accuracy of 0.62 (95% CI: 0.59-0.65). This performance significantly improved to an average accuracy of 0.77 (95% CI: 0.75-0.79) when images were pre-processed, enhanced and treated with a Local Binary Pattern operator (mean difference 0.15: 95% 0.11-0.19, p < 0.0001, two-tailed t test).

CONCLUSION

We have shown that an SVM can classify static 2D B mode ultrasound images of ovarian masses into benign and malignant categories. The accuracy improves if texture related LBP features extracted from the images are considered.

Source apportion of atmospheric particulate matter: a joint Eulerian/Lagrangian approach

PM2.5 samples were collected during an annual monitoring campaign (January 2012-January 2013) in the urban area of Naples, one of the major cities in Southern Italy. Samples were collected by means of a standard gravimetric sampler (Tecora Echo model) and characterized from a chemical point of view by ion chromatography. As a result, 143 samples together with their ionic composition have been collected. We extend traditional source apportionment techniques, usually based on multivariate factor analysis, interpreting the chemical analysis results within a Lagrangian framework. The Hybrid Single-Particle Lagrangian Integrated Trajectory Model (HYSPLIT) model was used, providing linkages to the source regions in the upwind areas. Results were analyzed in order to quantify the relative weight of different source types/areas. Model results suggested that PM concentrations are strongly affected not only by local emissions but also by transboundary emissions, especially from the Eastern and Northern European countries and African Saharan dust episodes.

The effectiveness and durability of an early insulin pump therapy in children and adolescents with type 1 diabetes mellitus

BACKGROUND

This study evaluated the predictors of effectiveness and durability of insulin pump therapy in children and adolescents who have initiated continuous subcutaneous insulin infusion (CSII) within 2 years after the diagnosis of type 1 diabetes mellitus (T1DM).

SUBJECTS AND METHODS

The charts of individuals with T1DM using insulin pumps who were treated at our center were reviewed, including subjects with age at onset of <22 years, interval between onset and insulin pump commencement (interval onset-commencement) of <2 years, use of pumps of >1 year, and use of glucose sensors for <4 weeks/year. The primary end point was the mean glycosylated hemoglobin (HbA1c) value (MHbA1c) throughout the follow-up.

RESULTS

From 684 patients treated with insulin pumps, 119 met the inclusion criteria, and 113 were selected for statistical analysis (60 females; age at diabetes onset, 8.9±5.6 years [mean±SD]; follow-up, 4.0±1.8 years; range, 1-8 years; baseline HbA1c, 9.3±1.8%). Only the interval onset-commencement was a linear predictor of the MHbA1c (P=0.01; R(2)=0.089). A significant reduction of the mean yearly HbA1c from baseline throughout all the follow-up was observed (P<0.001). Categorizing the sample into four quartiles on the basis of an increasing interval onset-commencement resulted in levels of MHbA1c significantly lower in the first and second quartiles in comparison with the fourth quartile (7.6±0.8% and 7.8±1.0%, respectively, versus 8.5±0.8%; P<0.001 and P=0.004, respectively).

CONCLUSIONS

The present study suggests that early pump commencement in children and adolescents with T1DM provides lower and more durable HbA1c values than a late commencement. It is possible that an early pump commencement could prolong the honeymoon phase, but we cannot confirm or exclude this hypothesis because the lack of data about C-peptide levels during the follow-up.

An assessment of contamination of the Fusaro Lagoon (Campania Province, southern Italy) by trace metals

The Fusaro Lagoon is a shallow lagoon, located in SW Italy, largely influenced in the last decades by several anthropic impacts. The study examined the pollution status of the lagoon, during year 2011-2012 at nine sampling stations with the aim to find out proper measurements of water lagoon restoration. Concentrations of heavy metals (HMs) (aluminium [Al], barium [Ba], cadmium [Cd], copper [Cu], iron [Fe], manganese [Mn], vanadium [V] and zinc [Zn]) were examined in water, sediments and specimens of the ascidian Ciona intestinalis sp. A. Low levels of dissolved oxygen concentration were detected at many stations, with mean values of 5.2-6.4 mg L(-1). The redox potential of surface waters was also low, -2.7 to 50.7 mV. Sediments possessed high organic matter content, 17.7-29.4%. In sediments, the mean Zn level, 251.4 mg kg(-1), was about sixfold higher than that recorded in year 2000 (38.5 mg kg(-1)) and considerably higher than that recorded in 2007 (191 mg kg(-1)). The mean levels of Cd were outstandingly high, with a mean value of 70.5 mg kg(-1), about 30- and 50-fold higher than those determined in 2000 and 2007, respectively. Cadmium (Cd), Cu and nickel (Ni) appeared in excess with respect to most current guidelines, reaching significant pollution levels. C. intestinalis sp. A was detected only at few stations, with metals accumulated preferentially in the body in respect to the tunic, from 1.2 times for Zn (178 mg kg(-1)) to 4.0 times for V (304 mg kg(-1)). Data suggests the necessity of an immediate action of eco-compatible interventions for environmental restoration.

Focusing and imaging with increased numerical apertures through multimode fibers with micro-fabricated optics

The use of individual multimode optical fibers in endoscopy applications has the potential to provide highly miniaturized and noninvasive probes for microscopy and optical micromanipulation. A few different strategies have been proposed recently, but they all suffer from intrinsically low resolution related to the low numerical aperture of multimode fibers. Here, we show that two-photon polymerization allows for direct fabrication of micro-optics components on the fiber end, resulting in an increase of the numerical aperture to a value that is close to 1. Coupling light into the fiber through a spatial light modulator, we were able to optically scan a submicrometer spot (300 nm FWHM) over an extended region, facing the opposite fiber end. Fluorescence imaging with improved resolution is also demonstrated.

Evaluation of sediment contamination by heavy metals, organochlorinated pesticides, and polycyclic aromatic hydrocarbons in the Berre coastal lagoon (southeast France)

During the last decades, the Berre lagoon, located in southeastern France, has been deeply affected by strong contaminant inputs. Surveys of surface sediment contamination have been sparsely performed since 1964 with data often disconnected with regard to time and space. To contribute to filling this gap, this study examined the pollution status of the lagoon during a 2012 sampling. Concentrations of heavy metals (HMs) (cadmium [Cd], chromium [Cr], copper [Cu], lead [Pb], and zinc [Zn]), organochlorine pesticides (OCPs), and polycyclic aromatic hydrocarbons were examined. The available seawater metal fraction was also investigated. Water from the Vaine basin (VB; stations 1 through 6) exhibited the lowest oxygen concentration (mean O₂% saturation 38.9%). HM loads were in the order of Zn > Cr > Pb > Cu > Cd with overall concentration ranges of 0.20-1.40 mg kg(-1) for Cd, 17.1-119 mg kg(-1) for Cr, 7.0-60.7 g(-1) for Cu, 12.0-104 mg kg(-1) for Pb, and 56.5-215 mg kg(-1) for Zn. Although HMs accumulated at levels largely exceeding their relative natural background level of 11-fold for Pb and 80-fold for Zn, their mean concentrations decreased largely to below the acceptable legal limits. HM loads were 20 to threefold the relative corresponding value of the threshold effect level benchmark of potential biological risk. Metals were only scantly released by sediments with mean percentage release of 0.99% for Cd and 40.2% for Cr with a peak for this latter element of 99% in the VB sector. In the case of OCPs, sediments appeared to be significantly polluted, especially in the VB area, with a mean lindane concentration of 0.05 mg kg(-1), which is ≤ fivefold the legal threshold. Among PAHs, benzo[a]pyrene exceeded the permitted limit of 0.1 mg kg(-1) mainly in the VB sector.

Prognostic accuracy of continuous glucose monitoring in the prediction of diabetes mellitus in children with incidental hyperglycemia: receiver operating characteristic analysis

AIM

The purpose of this study is to evaluate continuous glucose monitoring (CGM) in predicting diabetes mellitus in children with incident hyperglycemia (IH) and negativity for some insular autoantibodies.

SUBJECTS AND METHODS

Thirty-one autoantibody-negative children who presented at our center with IH underwent a baseline assessment and were followed up for 23.8 months (range, 6-48 months). At the end of the follow-up, we compared the receiver operating characteristic (ROC) areas under the curve (AUCs) of metabolic markers from 17 children who developed diabetes (Group A; n=17) and 14 children who did not develop diabetes (Group B; n=14).

RESULTS

Only two oral glucose tolerance test (OGTT)-derived markers and three CGM-derived markers showed a good prognostic performance, with ROC AUCs indicating significant results (P<0.0001) for the following markers: 2-h glucose, OGTT (0.813; 95% confidence interval [CI] 0.621-0.954); AUC glucose, OGTT (0.832; 95% CI 0.611-0.950); CGM glucose measurement peak (0.803; 95% CI 0.621-0.923); percentage of CGM glucose measurements inside the range 70-125 mg/dL (0.866; 95% CI 0.695-0.961); and percentage of CGM measurements ≥126 mg/dL (0.889; 95% CI 0.724-0.973). The combination of the OGTT-derived markers did not increase the predictive value, but the combination of CGM markers with each other or with the OGTT markers yielded higher ROC AUCs (ranging from 0.828 to 0.945).

CONCLUSIONS

This is the first study showing that CGM is useful in predicting diabetes mellitus in children with IH.

Geochemical survey of an illegal waste disposal site under a waste emergency scenario (Northwest Naples, Italy)

Since the mid 1980s, Naples and the Campania region have suffered from the dumping of wastes into overfilled landfills. The aim was to characterise a former cave located in Roccarainola (Naples, Italy) for its eventual destination to a controlled landfill site. A detailed hydro-geochemical survey of the area was carried out through drilling of 14 boreholes and four monitoring wells. Samples of water, sediment and soil were analysed for heavy metals and organic contaminants from a dew pond placed in the middle of the cave. The underneath aquifer was also surveyed. The nature of gases emitted from the site was investigated. Results of the geognostic survey revealed the presence of huge volumes of composite wastes, approximately half a million of cubic metre, which accumulated up to a thickness of 25.6 m. In some points, wastes lie below the free surface level of the aquifer. The sampled material from the boreholes revealed levels of As, Cd, Cr, Cu, Hg, Pb, Sn, Tl and Zn exceeding the intervention legal limits. Outstanding loads of Cd, Pb and Zn were found, with levels exceeding of about 50, 100 and 1,870 times the limit. In several points, polycyclic aromatic hydrocarbon load was extremely high, 35 vs 1 mg kg(-1) of the threshold. The aquifer was also very heavily polluted by Cd, Cr-tot, Cu, Fe, Mn, Ni, Pb and Zn, with impressive high load of Cr and Mn, up to 250-370 times the limits. Hot gases up to 62 °C with presence of xylene and ethylbenzene were found. Results indicated that the site needs an urgent intervention of recovery to avoid compromising the surrounding areas and aquifers of the Campania plain.

Integrated microfluidic device for single-cell trapping and spectroscopy

Optofluidic microsystems are key components towards lab-on-a-chip devices for manipulation and analysis of biological specimens. In particular, the integration of optical tweezers (OT) in these devices allows stable sample trapping, while making available mechanical, chemical and spectroscopic analyses.

Intraductal papillary mucinous neoplasm of the pancreas. Personal series and synthetic review

Intraductal papillary mucinous neoplasms (IPMNs) are rare pancreatic tumors, accounting for less than 1-2% of all neoplasms of the pancreas. The main characteristic of IPMNs is their favorable prognosis, as these pre-malignant or malignant lesions are usually slow-growing tumors and radical surgery is frequently possible. According to the localization of the lesions, three different tumor types have been identified: the main-duct IPMN, the branch-duct IPMN and the mixed-type IPMN (involving both the main pancreatic duct and the side branches). IMPNs do not present pathognomonic signs or symptoms. The obstruction of the main pancreatic duct system may cause abdominal pain and acute pancreatitis (single or recurrent episodes). The tumor may be incidentally discovered in asymptomatic patients, particularly in those with branch-duct IPMNs. In clinical practice, any non-inflammatory cystic lesion of the pancreas should be considered as possible IPMN. Computed tomography, magnetic resonance imaging with cholangiopancreatography and endoscopic ultrasonography can localize an IPMN and assess its morphology and size. The choice between non-operative and surgical management depends on the risk of malignancy and on the definitive distinction between benign and malignant IPMNs. Main-duct IPMNs have a high risk of malignant degeneration, especially in older patients. The clinical and radiological features, as well as treatment and outcome, of eight patients with IPMN (five with main-duct, two with branch-duct and one with mixed-type) observed by the authors over the last ten years are presented.

Genomic characterization and chromosomal mapping of 5 river buffalo skeletal muscle differentiation master genes

River buffalo (Bubalus bubalis, 2n = 50, BBU) is a species of economic relevance in a number of countries. This species shows a very peculiar biology and a great capacity for environmental adaptation. There has been an increasing economic interest as well as a growing demand for a more detailed knowledge of molecular features in this species. From this perspective we report a genomic, transcriptional and cytogenetic analysis of 5 master genes involved in skeletal muscle development. Of these 5 genes, MYOD1, MYF5, MYF6 and MYOG belong to the basic helix-loop helix protein family while MSTN belongs to the TNF-B protein family. In mammals, these genes are involved in the early stages of skeletal muscle differentiation, development and regeneration. These pivotal biological functions are finely regulated in a tissue- and temporal-specific manner. We used a comparative genomic approach to obtain the buffalo specific sequences of MYOD1 and MYF6. The nucleotide sequence similarity and the protein domain conservation of the newly obtained sequences are analysed with respect to bovine and other mammalian species showing sequence similarity. The presence of a polymorphism in MYOD1 coding sequence is described and its possible effect discussed. Using a quantitative PCR approach, we compared the level of the 5 transcripts in adult and fetal muscle. These genes were physically localised on river buffalo R-banded chromosomes by FISH using bovine genomic BAC-clones. Here, we present a genomic and cytogenetic analysis which could offer a background to better characterise the buffalo genes involved in muscle function and which may be responsible for buffalo-specific meat features.

Femtosecond laser fabricated monolithic chip for optical trapping and stretching of single cells

We report on the fabrication by a femtosecond laser of an optofluidic device for optical trapping and stretching of single cells. Versatility and three-dimensional capabilities of this fabrication technology provide straightforward and extremely accurate alignment between the optical and fluidic components. Optical trapping and stretching of single red blood cells are demonstrated, thus proving the effectiveness of the proposed device as a monolithic optical stretcher. Our results pave the way for a new class of optofluidic devices for single cell analysis, in which, taking advantage of the flexibility of femtosecond laser micromachining, it is possible to further integrate sensing and sorting functions.

The high resolution G- and R-banding pattern in chromosomes of river buffalo (Bubalus bubalis L.)

High resolution G- and R-banding patterns in chromosomes of river buffalo (Bubalus bubalis L.) were obtained by using early (G-bands) and late (R-bands) BrdU-incorporation in synchronized cell cultures. To better characterize the river buffalo chromosomes, GTG-, GBG-, and RBG-techniques were used. The total number of bands achieved were 490 (207 G-positive, 207 R-positive, 45 variable, and 31 centromeric regions). Only one common G- and R-banding nomenclature was reported. The number, position and intensity of G bands were highly similar by the structural GTG and the replicating GBG-techniques. However, the replicating G- and R-bands appeared to be more distinct and reproducible than the structural G-bands. Some changes in chromosome nomenclature (chromosomes 1p, 2p, 5p, and 21) were made when referred to the cattle homologues.

Sister chromatid exchange in chromosomes of cattle from three different breeds reared under similar conditions

A homogeneous group (same sex, age and environmental conditions) of 35 Italian cattle of the Podolian, Friesian, and Romagna breeds was investigated concerning the spontaneous incidence of sister chromatid exchange (SCE). The mean values of SCEs/cell were 7.9 +/- 3.4, 7.1 +/- 3.3, and 7.3 +/- 3.2 in the Podolian, the Friesian, and the Romagna breeds, respectively, with significant differences between the Podolian and the Friesian breeds. Simultaneous disclosure of SCEs and fluorescent G-bands in the lighter chromatid made possible the identification of chromosome 1, in addition to the biarmed X and Y chromosomes. The inter-chromosomal SCE-distribution revealed a nonrandom pattern due to significantly increased values of SCEs in chromosomes 1 and X, particularly in the Romagna breed.

High-resolution studies on late-replicating segments (G + C bands) in mammalian chromosomes

High resolution of late-replicating segments (G + C bands) in chromosomes of human, cattle and water buffalo was obtained by using 5-bromodeoxyuridine incorporation early in the cell cycle, simultaneous with methotrexate treatment combined with reduced colcemid treatment and addition of ethidium bromide, which increased the proportion of prometaphase cells. Giemsa counterstaining, following fluorescence microscopy observation and treatment with 2 x SSC, improved the resolution of the banding patterns, particularly in the pericentromeric regions. Acrocentric bovine and water buffalo chromosomes, which were seen to be C-positive by fluorescence microscopy observation and C-negative after counterstaining, showed the presence of subcentromeric G-positive bands within the heterochromatic blocks of several chromosomes.

Results from the integrated surveillance system for the 2006 Winter Olympic and Paralympic Games in Italy

An integrated epidemiological surveillance and response system was set up for the 2006 Olympic Winter Games in Torino [1] between 1 February

Integrated management of TYLCV/TYLCSV on greenhouse hydroponic tomatoes in Southern Italy

Tomato yellow leaf curl (TYLC) caused by Tomato yellow leaf curl virus (TYLCV) and Tomato yellow leaf curl Sardinia virus (TYLCSV), vectored by the whitefly Bemisia tabaci, is a major disease of tomato in Sardinia and Sicily, and is becoming a serious threat in Southern Italy too. TYLCSV was first reported in Calabria region in 1991, but apparently it was an occasional outbreak, and B. tabaci was not detected. Later, during the 2003-2004 winter, a serious epidemic was observed in protected tomato crops in Castrovillari, Cosenza province. TYLCV was first described in Sicily in 2003 and during 2004 in continental Italy. Both viruses were detected in winter 2005-2006 on the Basilicata Ionic coast, in the Metapontum area, both in protected and in open field tomato crops. Experiments were conducted in Calabria Region, Southern Italy, under controlled conditions in a group of greenhouses where several tomato crops were grown hydroponically to determine the separate and integrated effects of UV-reflective mulch (UVRM), Acibenzolar-S-methyl (Actigard) and the two insecticides Imidacloprid (ADMIRE 2F) and Thiamethoxam (ACTARA 25WG). Highly UV-reflective mulch covered plots were treated with Actigard and insecticides, both alone or in combination. TYLC disease incidence was determined from late August 2005 to late January 2006. The highly UVRM alone was effective in reducing disease incidence of about 28.6% at the end of October, and of 31.7% at the end of January. However, Actigard with UVRM significantly reduced TYLC disease incidence to 70% and 48.5%, in 2 months and 5 months after the first treatment, respectively. The insecticides with UVRM, resulted in a moderate reduction of disease incidence (22.5%) at the end of October. At the end of January a reduction in disease incidence due to insecticide applications was not significant. The use of Actigard combined with the insecticides on UVRM reduced the disease incidence (63.4% with Admire and 56.1% with Actara) at the end of January. Actigard alone or with insecticides on UVRM was effective in reducing disease incidences. Highly UVRM and Actigard were effective in reducing the primary spread of TYLCV/TYLCSV in greenhouse hydroponic tomatoes. Comparative analysis of their effects at different periods post-treatment suggests that multiple applications of Actigard may be necessary to reduce progress of this disease.

Gene therapy progress and prospects: targeted gene repair

The capacity to correct a mutant gene within the context of the chromosome holds great promise as a therapy for inherited disorders but fulfilling this promise has proven to be challenging. However, steady progress is being made and the development of gene repair as a viable and robust approach is underway. Here, we present some of the recent advances that are helping to shape our thinking about the feasibility and the limitations of this technique. For the most part, these advances center on understanding the regulation of the reaction and validating its application in animal models.

A new centric fusion translocation in cattle, rob(16;18)

A Barrosã bull (Portugal) has been found to carry a new Robertsonian translocation involving chromosomes 16 and 18 of standard cattle karyotype, as demonstrated by GBG- and RBG-banding techniques. C-banding patterns revealed the dicentric nature of this translocation. A comparison between normal cattle chromosome 16 and the q-arms of translocation chromosome and river buffalo chromosome 5 revealed the same G- and R-banding patterns, with only exception of a pericentromeric G-positive band which has been lost in river buffalo 5q and conserved in normal cattle chromosome 16 and rob(16;18) q-arms.

Sister chromatid exchange in the goat (Capra hircus)

Lymphocyte cells from 30 Maltese and Syrian derivative goats (13 males and 17 females) reared in southern Italy underwent sister chromatid exchange (SCE) test. For the 902 cells we studied, the SCE-mean values were 6.6 +/- 3.0 per cell for both breeds. The SCE-frequency did not follow a Poisson distribution. The simultaneous visualization of SCEs and G-bands in the lightly stained chromatid allowed the study of SCE-distribution in chromosomes 1 and X. The number of SCEs in chromosome 1 was significantly higher (P > 0.001) than expected from relative chromosome length. No statistical differences between the numbers of SCEs in the active (early-replicating) and inactive (late-replicating) X-chromosomes of female cells were found.

Effects of different dairy products on postprandial lipemia

BACKGROUND AND AIM

To evaluate the effects on postprandial lipemia (PPL), of three fat rich meals, with similar composition but different physical structure (liquid, semisolid and solid).

METHODS AND RESULTS

Eight type 2 diabetic patients of both genders (6M/2F), age 51+/-9 yrs (M+/-SD), BMI 29+/-3 kg/m2, with fasting plasma glucose levels 145+/-24 mg/dL, cholesterol 200+/-38 mg/dL and triglyceride 110+/-45 mg/dL. Participants consumed in the morning, after a 12-hour fast and at 1-week intervals, three test meals with similar volume and composition [protein 36 g, lipid 30 g, carbohydrate 115 g, energy 3556 kJ (850 Kcal)] but with the main source of fat represented by foods with different physical structure (milk, mozzarella-cheese, butter). Each patient underwent gastric emptying measurements by echography; plasma FFA, triglycerides, glucose and insulin were evaluated at baseline and every hour for six hours after each meal. Fasting plasma glucose, cholesterol and triglyceride concentrations were similar at the baseline of the three test meals. Average increases in postprandial plasma triglyceride levels after butter (88+/-8 mg/dL) and mozzarella-cheese (104+/-56 mg/dL) were not different than after milk (98+/-53 mg/dL). The plasma triglyceride peak was also similar after the three test meals but peak time after butter (315+/-42 min; p<0.01) and mozzarella-cheese (277+/-31 min; p<0.02) was significantly delayed compared to milk (225+/-28 min). Gastric emptying rate was similar after butter and milk (14+/-2, 13+/-6 mL/h) and significantly faster after mozzarella-cheese (18+/-5 mL/h; p<0.03).

CONCLUSIONS

While the physical structure of fat-rich foods has no major effect on postprandial plasma triglyceride concentrations, it is able to influence the timing of triglyceride peak; gastric emptying time does not play a major role in modulating the postprandial response of triglycerides and glucose.

The accumulation of alpha-Tocopherol and Retinol in the milk of water buffalo is correlated with the plasma levels of triiodothyronine

Milk is the most important source of Retinol and alpha-Tocopherol for calves. These antioxidants save the food quality and prevent lipid oxidation in the mammary gland and the calf growing tissues. In Bubalus bubalis, seasonal changes for the plasma levels of both antioxidants were not found. The levels of Retinol and alpha-Tocopherol in the milk were 2 and 1.7 times higher in winter than in summer, respectively. These levels were correlated with the plasma level of triiodothyronine, and markedly increased in cows injected with triiodothyronine in summer. The cytosol from alveolar epithelial cells of mammary glands was incubated with alpha-Tocopherol and 3H-Retinol and, after gel filtration chromatography, both antioxidants were found associated with proteins migrating as a single peak of 33 kD. The amount of alpha-Tocopherol and Retinol binding proteins was 1.5 and 2.3 times higher in winter than in summer respectively. The Retinol binding proteins migrated as two bands (33 and 16 kD) by electrophoresis in denaturing and reducing conditions. Our data suggest that triiodothyronine enhances the transport of both liposoluble antioxidants through the blood-mammary barrier, and demonstrate that proteins of the mammary epithelial cells are involved in such a transport.

Bovine cytosolic 5'-nucleotidase acts through the formation of an aspartate 52-phosphoenzyme intermediate

Cytosolic 5'-nucleotidase/phosphotransferase (cN-II), specific for purine monophosphates and their deoxyderivatives, acts through the formation of a phosphoenzyme intermediate. Phosphate may either be released leading to 5'-mononucleotide hydrolysis or be transferred to an appropriate nucleoside acceptor, giving rise to a mononucleotide interconversion. Chemical reagents specifically modifying aspartate and glutamate residues inhibit the enzyme, and this inhibition is partially prevented by cN-II substrates and physiological inhibitors. Peptide mapping experiments with the phosphoenzyme previously treated with tritiated borohydride allowed isolation of a radiolabeled peptide. Sequence analysis demonstrated that radioactivity was associated with a hydroxymethyl derivative that resulted from reduction of the Asp-52-phosphate intermediate. Site-directed mutagenesis experiments confirmed the essential role of Asp-52 in the catalytic machinery of the enzyme and suggested also that Asp-54 assists in the formation of the acyl phosphate species. From sequence alignments we conclude that cytosolic 5'-nucleotidase, along with other nucleotidases, belong to a large superfamily of hydrolases with different substrate specificities and functional roles.

Bacterial expression and conformational analysis of a chemosensory protein from Schistocerca gregaria

Chemosensory proteins (CSPs) are a class of small, soluble proteins present at high concentrations in chemosensory organs of different insect species. Several pieces of evidence suggest their involvement in carrying chemical messages from the environment to chemosensory receptors. However, a structural description of the mechanism of delivery has not been reported. In order to provide the first detailed conformational characterization of these molecules, we cloned a specific isoform (CSP-sg4) from Schistocerca gregaria and expressed it in Escherichia coli. The product was obtained with yields of more than 20 mg per L of culture, all in its soluble form. The recombinant protein was identical to the native one with respect to pairing of the disulfide bridges, aggregative state and secondary structure elements. Structural investigations revealed a significantly stable polypeptide with respect to variations in temperature and acidity. CD analysis, preliminary NMR data and secondary structure prediction pointed to a correctly folded structure where helical regions and loops are alternated in a similar fashion as that observed for other classes of odorant- and pheromone-binding proteins presenting no sequence similarity to CSPs.

Purification, cloning and characterisation of odorant- and pheromone-binding proteins from pig nasal epithelium

Two distinct classes of lipocalin isoforms (OBP-IIs and OBP-IIIs) were purified and identified from porcine nasal mucosa of male and female individuals. Using primers designed on their N-terminal sequence, the complete primary structures of the mature polypeptides were determined. Mass spectrometry analysis confirmed the identity of the cDNA-derived sequences and provided information regarding their post-translational modifications. These species strongly resemble a lipocalin expressed by von Ebner's gland and salivary lipocalins carrying sex-specific pheromones secreted only by the boar's submaxillary glands. Both OBP-IIs and OBP-IIIs present two cysteines paired in a disulphide bond; the remaining residues occur in a reduced form. In addition, OBP-IIIs are heavily glycosylated and markedly different in their glycan moiety from the salivary lipocalins. A three-dimensional model is proposed based on protein species with known structure. Like salivary lipocalins, OBP-IIIs bind a number of odorant molecules, with highest affinity for the specific pheromone 5alpha-androst-16-en-3-one. The high similarity between OBPs from the nasal area and lipocalins from secretory glands suggests a common function in binding the same pheromonal ligands, the latter carrying chemical messages into the environment the former delivering them to specific receptors.