Photo Thermal Effect Graphene Detector Featuring 105 Gbit s-1 NRZ and 120 Gbit s-1 PAM4 Direct Detection

The challenge of next generation datacom and telecom communication is to increase the available bandwidth while reducing the size, cost and power consumption of photonic integrated circuits. Silicon (Si) photonics has emerged as a viable solution to reach these objectives. Graphene, a single-atom thick layer of carbon5, has been recently proposed to be integrated with Si photonics because of its very high mobility, fast carrier dynamics and ultra-broadband optical properties. Here, we focus on graphene photodetectors for high speed datacom and telecom applications. High speed graphene photodetectors have been demonstrated so far, however the most are based on the photo-bolometric (PB) or photo-conductive (PC) effect. These devices are characterized by large dark current, in the order of milli-Amperes , which is an impairment in photo-receivers design, Photo-thermo-electric (PTE) effect has been identified as an alternative phenomenon for light detection. The main advantages of PTE-based photodetectors are the optical power to voltage conversion, zero-bias operation and ultra-fast response. Graphene PTE-based photodetectors have been reported in literature, however high-speed optical signal detection has not been shown. Here, we report on an optimized graphene PTE-based photodetector with flat frequency response up to 65 GHz. Thanks to the optimized design we demonstrate a system test leading to direct detection of 105 Gbit s-1 non-return to zero (NRZ) and 120 Gbit s-1 4-level pulse amplitude modulation (PAM) optical signal

Non-invasive assessment of liver steatosis and fibrosis in HIV/HCV- and HCV- infected patients

Background. Conflicting data have been reported on the prevalence of liver steatosis, its risk factors and its relationship with fibrosis in patients with human immunodeficiency virus (HIV)/hepatitis C virus (HCV) co-infection or with HCV mono-infection. Aim. The study aims were to assess steatosis prevalence and its risk factors in both HCV groups. We also evaluated whether steatosis was linked with advanced fibrosis. Sixty-eight HIV/HCV co-infected and 69 HCV mono-infected patients were consecutively enrolled. They underwent liver ultrasonography and transient elastography. Bright liver echo-pattern was used to diagnose steatosis; advanced fibrosis was defined as liver stiffness ≥ 9.5 kPa and FIB-4 values ≥ 3.25. The optimal stiffness cut-off according to FIB-4 ≥ 3.25 was evaluated by ROC analysis. Results. No significant difference was found in steatosis-prevalence between mono- and co-infected patients (46.3 vs. 51.4%). Steatosis was associated with triglycerides and impaired fasting glucose/diabetes in HCV mono-infected, with lipodystrophy, metabolic syndrome, total-cholesterol and triglycerides in co-infected patients. Stiffness ≥ 9.5 was significantly more frequent in co-infection (P < 0.003). Advanced fibrosis wasn't significantly associated with steatosis. The area under the ROC curve was 0.85 (95% CI 0.79-0.9). On multivariate analysis steatosis was associated with triglycerides in both HCV mono- and co-infected groups (P < 0.02; P < 0.03). Conclusion. Although steatosis was common in both HCV mono- and co-infected patients, it was not linked with advanced fibrosis. Triglycerides were independent predictors of steatosis in either of the HCV-groups. Dietary interventions and lifestyle changes should be proposed to prevent metabolic risk factors

Osteoporosis risk factors in HIV positive women with osteoporosis: A retrospective analysis

Multifactorial risk factors such as HIV/HCV co-infection and antiretroviral therapy (ARV) have been associated with osteoporosis in HIV+ women. We retrospectively analysed which known risk factors were associated with the diagnosis of osteoporosis, according to the WHO definition, in HIV positive women who were followed-up at the AIDS Centre of the University of Palermo, Italy between January 2011 and December 2014. Twenty-one HIV+ women with osteoporosis (13 HIV+ mono-infected and 8 HIV/HCV co-infected females) who underwent dual-energy X-ray absorptiometry (DXA) and liver stiffness assessment were included in the study. No significant differences between the HIV and HIV/HCV group were found regarding liver stiffness and lumbar/femoral osteoporosis scores. In a univariate analysis, we observed a positive linear correlation between LBD score (Lumbar Bone Density) with pre-fractures (p-value = 0.0082), smoke (p-value = 0.0008), alcohol (p-value &lt; 0.0001) and ARV exposure score (p-value = 0.0039), while there were no significant negative linear correlations. In multivariate analysis, pre-fractures, smoke and alcohol were positive predictors of LBD score, while previous antiretroviral therapy (ARV) (years) score was a negative predictor compared to others. Univariate analysis showed a positive linear correlation between FDB (Femoral Bone Density) with smoke (p-value = 0.0303) and alcohol (p-value = 0.0050), while there were no significant negative linear correlations. In multivariate analysis, alcohol was a positive predictor of FDB score compared to others, while ARV score was a negative predictor compared to others. This preliminary study suggests that other factors besides ARV score and liver fibrosis may affect the skeletal system in osteoporotic women with HIV infection. Some of these factors, such as alcohol and smoking, are modifiable. Additional research into impact on osteoporosis in HIV women with osteoporosis is required

The Prevalence of NAFLD and Fibrosis in Bariatric Surgery Patients and the Reliability of Noninvasive Diagnostic Methods

Background: Bariatric surgery patients have a higher prevalence of nonalcoholic fatty liver (NAFL) than the general population; however, its assessment and the accurate staging of fibrosis are often complicated because noninvasive tests are not very accurate in patients with morbid obesity, and liver biopsy cannot be performed as a routine exam. The aim of this study was to evaluate (A) the histological prevalence of NAFL, nonalcoholic steatohepatitis (NASH), and fibrosis in patients undergoing bariatric surgery; (B) the reliability of ultrasound (US) in diagnosing NAFL; and (C) the reliability of various fibrosis scoring systems for defining fibrosis. Methods: US and intraoperative liver biopsy results were reviewed in 57 bariatric surgery patients. NAFL, NASH, and fibrosis were diagnosed according to the Kleiner scoring system. US diagnosis of liver steatosis was based on the bright liver. Fibrosis scores used were (i) the BMI, AST/ALT Ratio, Diabetes (BARD) scoring system; (ii) the nonalcoholic fatty liver disease (NAFLD) fibrosis score; and (iii) the fibrosis-4 (FIB-4) index. Results: The prevalence of NAFL was 81%, NASH 61.4%, and fibrosis 94% (F3 5.7%, cirrhosis 2.8%). The sensitivity of US was 95%, specificity 50%, and likelihood ratio (LR+, LR-) 1.91 and 0.1. The reliability of fibrosis scores for F ≥ 2 were as follows: BARD score: sensitivity 46%, specificity 54%, and area under the receiver-operating characteristics (AUROC) curve 0.5; NAFLD score: sensitivity 30%, specificity 89%, and AUROC 0.5; and FIB-4: sensitivity 68%, specificity 67%, and AUROC 0.7. Conclusions: In bariatric surgery patients, the prevalence of NAFL was 81%, NASH 61.4%, and fibrosis 94%. US is able to rule out the presence of NAFL, while the commonly used scores may be inaccurate in defining fibrosis in patients with morbid obesity

MODIFICAZIONI ECOGRAFICHE DELLA LINFADENOPATIA DELL’ILO EPATICO DOPO ERADICAZIONE DELL’HCV CON DIRECT-ACTING ANTIVIRALS

A) Valutare le modificazioni ecografiche (US) dei linfonodi (LN) dell’ilo epatico in pazienti con epatopatia cronica (EC) correlata al virus dell’epatite C (HCV) e Sustained Virological Responders (SVR) alla terapia con i Direct-Acting Antivirals (DAAs); B) rilevare i fattori predittivi correlati con la scomparsa di LN. Abbiamo studiato 177 pazienti, trattati con DAAs, arruolati consecutivamente tra il Gennaio 2015 e il Dicembre 2016, con un follow-up dell’SVR di 24 mesi (SVR24) a Dicembre 2018; erano esclusi i pazienti con storia o insorgenza di epatocarcinoma nel follow-up. I LN erano definiti ingranditi (LN+) se il diametro maggiore era &gt;1 cm. Al baseline (BL) registravamo: età, sesso, BMI, markers HBV, HCV e genotipo, uso di alcol; valutavamo al BL, a 12 mesi (SVR12) e a 24 mesi: test di funzione epatica, HCV-RNA, liver stiffness (Fibroscan), diametri US di vena porta e milza. La prevalenza di LN+ al BL era 49.8%, il diametro 2.1±0.6 cm, in LN+ vs LN- le transaminasi erano più elevate (P&lt;0.05). A SVR12 la prevalenza di LN+ era 32.2 %; in LN+ vs LNs (pazienti in cui erano scomparsi) dei parametri studiati solo l’età era maggiore (P&lt;0.05). Il diametro dei LN+ a SVR12 era 1.8±0.4 cm, ridotto rispetto al BL (P&lt;0.05). A SVR24 la prevalenza di LN+ era 29.3 % inferiore vs BL (P&lt;0.001), solo l’età si confermava maggiore vs LNs (P&lt;0.03). Il diametro di LN+ era 1.7±0.5 minore che al BL (P&lt;0.05), sovrapponibile a SVR12 (P=ns). Nelle EC da HCV è frequente il rilievo US di LN all’ilo epatico, considerati indice di grading e staging istologici epatici più severi ed espressione del linfotropismo virale. Alla luce di questi presupposti i LN dovrebbero scomparire dopo l’eradicazione dell’infezione HCV, a questo proposito gli studi dopo terapia con Interferone sono contrastanti. Nel nostro studio LN+ al BL correla con AST e ALT confermando la relazione con l’attività necro-infiammatoria epatica. A SVR24 la prevalenza di LN+ è del 29.4% significativamente ridotta che al BL. IL diametro dei LN+ residui diminuisce a SVR12 per poi stabilizzarsi. La causa della persistenza di LN è controversa, l’assenza di relazione tra LN+ residui ed indici di funzione e fibrosi epatica ci fa ipotizzare che non dipenda più dall’attività della malattia epatica, ma da altre variabili, una potrebbe essere la diversa attività immunologica instauratasi dopo l’eradicazione virale, a conferma di ciò va ricordato che nel 20 % dei soggetti sani è possibile rilevare LN all’ilo epatico (J.Hepatol.2003;39:807), dato questo simile al nostro 29.4 %

Risk factors for hepatitis C virus infection among blood donors in southern Brazil: a case-control study

BACKGROUND: In Brazil, it is estimated that between 2.5 and 4.9% of the general population present anti-hepatitis C virus (HCV) antibodies, which corresponds to as many as 3.9 to 7.6 million chronic carriers. Chronic liver disease is associated with HCV infection in 20% to 58% of the Brazilian patients. The objective of this case-control study was to investigate the risk factors for presence of anti-HCV antibody in blood donors in southern Brazil. METHODS: One hundred and seventy eight blood donors with two positive ELISA results for anti-HCV were cases, and 356 controls tested negative. A standardized questionnaire was used to collect data concerning demographic and socioeconomic aspects, history of previous hepatitis infection, social and sexual behaviors, and number of donations. Variables were grouped into sets of hierarchical categories. Cases and controls were compared using logistic regression, odds ratios, and 95% confidence intervals. The statistical significance of the associations was assessed through likelihood ratio tests based on a P value < 0.05. RESULTS: The prevalence of anti-HCV among blood donors was 1.1%. Most of the donors were white and males. In the multivariate analysis, independent predictors of anti-HCV positivity were: intravenous drug use, blood transfusion >10 years earlier, having had two to four sexually transmitted diseases, incarceration, tattooing, sex with a hepatitis B or C virus carrier or with intravenous drug users. CONCLUSION: Intravenous drug use, blood transfusion, and tattooing were the main risk factors for anti-HCV positivity among blood donors from southern Brazil, but sexual HCV transmission should also be considered

Induction chemotherapy followed by concurrent standard radiotherapy and daily low-dose cisplatin in locally advanced non-small-cell lung cancer

Both induction chemotherapy and concurrent low-dose cisplatin have been shown to improve results of thoracic irradiation in the treatment of locally advanced non-small-cell lung cancer (NSCLC). This phase II study was designed to investigate activity and feasibility of a novel chemoradiation regimen consisting of induction chemotherapy followed by standard radiotherapy and concurrent daily low-dose cisplatin. Previously untreated patients with histologically/cytologically proven unresectable stage IIIA/B NSCLC were eligible. Induction chemotherapy consisted of vinblastine 5 mg m−2 intravenously (i.v.) on days 1, 8, 15, 22 and 29, and cisplatin 100 mg m−2 i.v. on days 1 and 22 followed by continuous radiotherapy (60 Gy in 30 fractions) given concurrently with daily cisplatin at a dose of 5 mg m−2 i.v. Thirty-two patients were enrolled. Major toxicity during induction chemotherapy was haematological: grade III–IV leukopenia was observed in 31% and grade II anaemia in 16% of the patients. The most common severe toxicity during concurrent chemoradiation consisted of grade III leukopenia (21% of the patients); grade III oesophagitis occurred in only two patients and pulmonary toxicity in one patient who died of this complication. Eighteen of 32 patients (56%, 95% CI 38–73%) had a major response (11 partial response, seven complete response). With a median follow-up of 38.4 months, the median survival was 12.5 months and the actuarial survival rates at 1, 2 and 3 years were 52%, 26% and 19% respectively. The median event-free survival was 8.3 months with a probability of 40%, 23% and 20% at 1, 2 and 3 years respectively. Induction chemotherapy followed by concurrent daily low-dose cisplatin and thoracic irradiation, in patients with locally advanced NSCLC, is active and feasible with minimal non-haematological toxicity. Long-term survival results are promising and appear to be similar to those of more toxic chemoradiation regimens, warranting further testing of this novel chemoradiation strategy. © 1999 Cancer Research Campaig