Biosensors consist of a biocatalyst that can detect a biological element and a transducer which can convert the combination event of the biocatalyst and the biological element into a detectable parameter. The biocatalyst can be biomolecules like, enzyme, DNA, RNA, metabolites, cells, oligonucleotides etc., and the transducers can be electrochemical, optical, piezoelectric, acoustics, calorimetric etc. In disease diagnostics biosensors utilizing immobilized cells, enzymes, nucleic acids have come into the field in recent years. Nanobiosensors exploiting the ultrasmall size and unique properties have also been used for engineering disease diagnostic biosensors. The use of biosensors can rapidly assess the health status, onset of the disease and its progression and can help to plan treatment for many diseases with the aid of multidisciplinary combination of chemistry, medical science and nanotechnology. The devices are cost effective, highly sensitive, rapid, user friendly and can be produced in bulk for human use. This review focuses on the different biosensors for the diagnosis of three major diseases like diabetes, cardiovascular disease and cancer.

Diagnostic biosensors in medicine – A review

Prediction of the risk of hereditary retinoblastoma, using DNA polymorphisms within the retinoblastoma gene

Retinoblastoma (RB) is a rare childhood malignant disorder caused by the biallelic inactivation of RB1 gene. Early diagnosis and identification of carriers of heritable RB1 mutations can improve disease outcome and management. In this study, mutational analysis was conducted on fifty-nine matched tumor and peripheral blood samples from 18 bilateral and 41 unilateral unrelated RB cases by a combinatorial approach of Multiplex Ligation-dependent Probe Amplification (MLPA) assay, deletion screening, direct sequencing, copy number gene dosage analysis and methylation assays. Screening of both blood and tumor samples yielded a mutation detection rate of 94.9% (56/59) while only 42.4% (25/59) of mutations were detected if blood samples alone were analyzed. Biallelic mutations were observed in 43/59 (72.9%) of tumors screened. There were 3 cases (5.1%) in which no mutations could be detected and germline mutations were detected in 19.5% (8/41) of unilateral cases. A total of 61 point mutations were identified, of which 10 were novel. There was a high incidence of previously reported recurrent mutations, occurring at 38.98% (23/59) of all cases. Of interest were three cases of mosaic RB1 mutations detected in the blood from patients with unilateral retinoblastoma. Additionally, two germline mutations previously reported to be associated with low-penetrance phenotypes: missense-c.1981C>T and splice variant-c.607+1G>T, were observed in a bilateral and a unilateral proband, respectively. These findings have implications for genetic counselling and risk prediction for the affected families. This is the first published report on the spectrum of mutations in RB patients from Singapore and shows that further improved mutation screening strategies are required in order to provide a definitive molecular diagnosis for every case of RB. Our findings also underscore the importance of genetic testing in supporting individualized disease management plans for patients and asymptomatic family members carrying low-penetrance, germline mosaicism or heritable unilateral mutational phenotypes.

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Mutation spectrum of RB1 mutations in retinoblastoma cases from Singapore with implications for genetic management and counselling.

Green tea extract (GTE) supplementation has been proposed to possess anti-inflammatory properties. This study assessed the effects of GTE on endurance training (ET) induced changes on irisin, pro-inflammatory cytokines, adiponectin and anthropometric indices in overweight middle-aged males. Participants were randomly assigned to three groups (n = 15): endurance training + placebo (ET + P), endurance training + green tea extract supplementation (ET + GTE), and no endurance training + placebo (P). The ET intervention consisted of an 8-week training program that included circuit training, fast walking or jogging performed three times/week at a moderate intensity (40–59% of the heart rate reserve). Participants received 500 mg/day GTE using a green tea capsule. Serum concentrations of interleukin 6 (IL-6), tumor necrosis factor-alpha (TNF-α), irisin, adiponectin, and high-sensitivity C-reactive protein (hs-CRP) were measured prior to and after the 8-week training intervention. Both exercise interventions decreased IL-6 and hs-CRP (p < 0.05), and increased adiponectin (p < 0.01) levels; changes in these variables were greater in the ET + GTE group compared to the ET + P and P groups (p < 0.01). Irisin concentrations increased only in the ET + GTE group and were different from the ET + P and P groups (p < 0.01). There were no changes in TNF-α concentrations in any of the groups. Both exercise interventions (ET + GTE and ET + P) decreased bodyweight, body mass index (BMI), body fat percentage (BFP), and visceral fat area (VFA) (p < 0.05), with greater changes in these variables occurring in the ET + GTE group compared to ET + P and P groups (p < 0.01). The combination of GTE supplementation and ET produces beneficial anti-inflammatory and metabolic effects, which were greater than those produced by ET alone.

Effects of green tea extract supplementation and endurance training on irisin, pro-inflammatory cytokines, and adiponectin concentrations in overweight middle-aged men

The cereus matter of Bacillus endophthalmitis

Aims Green tea extract (GTE) can exert antiobesity and anti-inflammatory effects. Our study determined whether the benefits of GTE are summative with exercise-induced changes in anthropometric indices, and the levels of inflammatory cytokines, adiponectin and irisin in inactive overweight women. Methods Thirty overweight female participants were randomized to 3 groups: endurance training + placebo (ET + P); endurance training + GTE (ET + GTE); and Control (no exercise) + placebo (Control, n = 10). The exercise intervention consisted of an 8-week endurance-training programme of 3 sessions per week (aerobics, aerobic circuit training, and fast walking or jogging at a moderate intensity of 40-59% of the heart rate reserve). The dose of GTE used was 500 mg/day in the form of a green tea capsule. Results Body weight, body mass index, waist to hip ratio and body fat percentage were decreased in both ET + P and ET + GTE interventions (P .05). Conclusions GTE improves exercise-induced body composition by further decreasing exercise-induced changes in weight, body mass index, waist to hip ratio and body fat percentage. The combination of GTE and exercise also produced greater changes in anti-inflammatory (increases in adiponectin) and metabolic (decreases in hs-CRP) markers than exercise alone.

https://bpspubs.onlinelibrary.wiley.com/doi/pdf/10.1111/bcp.14176

Does green tea extract enhance the anti-inflammatory effects of exercise on fat loss?

OBJECTIVES The aims of this study were to investigate the effects of a six-week in-season period of soccer training and games (congested period) on plasma volume variations (PV), hematological parameters, and physical fitness in elite players. In addition, we analyzed relationships between training load, hematological parameters and players' physical fitness. METHODS Eighteen elite players were evaluated before (T1) and after (T2) a six-week in-season period interspersed with 10 soccer matches. At T1 and T2, players performed the Yo-Yo intermittent recovery test level 1 (YYIR1), the repeated shuttle sprint ability test (RSSA), the countermovement jump test (CMJ), and the squat jump test (SJ). In addition, PV and hematological parameters (erythrocytes [M/mm3], hematocrit [%], hemoglobin [g/dl], mean corpuscular volume [fl], mean corpuscular hemoglobin content [pg], and mean hemoglobin concentration [%]) were assessed. Daily ratings of perceived exertion (RPE) were monitored in order to quantify the internal training load. RESULTS From T1 to T2, significant performance declines were found for the YYIR1 (p<0.001, effect size [ES] = 0.5), RSSA (p<0.01, ES = 0.6) and SJ tests (p< 0.046, ES = 0.7). However, no significant changes were found for the CMJ (p = 0.86, ES = 0.1). Post-exercise, RSSA blood lactate (p<0.012, ES = 0.2) and PV (p<0.01, ES = 0.7) increased significantly from T1 to T2. A significant decrease was found from T1 to T2 for the erythrocyte value (p<0.002, ES = 0.5) and the hemoglobin concentration (p<0.018, ES = 0.8). The hematocrit percentage rate was also significantly lower (p<0.001, ES = 0.6) at T2. The mean corpuscular volume, mean corpuscular hemoglobin content and the mean hemoglobin content values were not statistically different from T1 to T2. No significant relationships were detected between training load parameters and percentage changes of hematological parameters. However, a significant relationship was observed between training load and changes in RSSA performance (r = -0.60; p<0.003). CONCLUSIONS An intensive period of "congested match play" over 6 weeks significantly compromised players' physical fitness. These changes were not related to hematological parameters, even though significant alterations were detected for selected measures.

/pdf/effects-of-a-six-week-period-of-congested-match-play-on-c5ej5j6yox.pdf

Effects of a six-week period of congested match play on plasma volume variations, hematological parameters, training workload and physical fitness in elite soccer players.

Retinoblastoma, an embryonic neoplasm of retinal origin, is the most common primary intraocular malignancy in children Somatic inactivation of both alleles of the RB1 tumor suppressor gene in a retinal progenitor cell through diverse mechanisms including genetic and epigenetic modifications, is the crucial event in initiation of tumorigenesis in most cases of isolated unilateral retinoblastoma We analyzed DNA from tumor tissue and from peripheral blood to determine the RB1 mutation status and seek correlations with clinical features of 37 unrelated cases of Tunisian origin with sporadic retinoblastoma All cases were unilateral except one who presented with bilateral disease, in whom no germline coding sequence alteration was identified A multi-step mutation scanning protocol identified bi-allelic inactivation of RB1 gene in 30 (81%) of the samples tested A total of 7 novel mutations were identified There were three tumors without any detectable mutation while a subset contained multiple mutations in RB1 gene The latter group included tumors collected after treatment with chemotherapy There were seven individuals with germline mutations and all presented with advanced stage of tumor There was no difference in age of onset of RB based on the germline mutation status Thus 20% of the individuals with sporadic unilateral RB in this series carried germline mutations and indicate the importance of genetic testing all children with sporadic retinoblastoma These findings help to characterize the spectrum of mutations present in the Tunisian population and can improve genetic diagnosis of retinoblastoma

Mutation spectrum of RB1 gene in unilateral retinoblastoma cases from Tunisia and correlations with clinical features.

BACKGROUND Postoperative endophthalmitis is a public health issue due to its bad prognosis; its treatment is both surgical and medical. Classically, surgical treatment was done if visual acuity is limited to light perception only. AIM To evaluate therapeutic results Of postoperative endophtalmitieS and to Compare therapeutics almost used intravitreal injection of antibiotics versus early vitrectomy. METHODS It's a retrospective comparative study  includIng 120 cases of acute postoperative endophthalmitis hospitalized in a referral ophthalmology department between July 2007 and June 2013. A comparison was conducted between two groups of 24 and 94 patients; the first-line treatment was early vitrectomy for the first group and intravitreal antibiotic injection alone for the second group. RESULTS The overall incidence rate was 0.38 %, Streptococcus and Staphylococcus Epidermidis where the most common bacterial strain (16 patients each). The treatment outcome was very favorable for 11 patients with final visual acuity  higher or equal to 2/10, the outcome was intermediate for 43 patients and poor for 66 patients because of final visual acuity lower than or equal to 1/20, loss of media transparency or anatomical or functional loss of the eye. The prognostic factors statistically correlated to treatment outcome where intense initial inflammation (p<0.001), high bacterial virulence (p=0.002), bacteria culture positive to Streptococcus (p=0.024), a defectuous operative incision (p= 0.012), age over 80 (p=0.022) and posterior capsule rupture (p=0.013). Early vitrectomy group (group1) achieved a higher percentage of good outcome (60% vs 41.5%,  p=0.098 ). CONCLUSION Functional result is better in the Vitrectomy group than in the antibiotic intravitreal injections group whereas not Statically signifiant.

Amel Chebbi

Papers

Does green tea extract enhance the anti-inflammatory effects of exercise on fat loss?

Effects of a six-week period of congested match play on plasma volume variations, hematological parameters, training workload and physical fitness in elite soccer players.

Mutation spectrum of RB1 gene in unilateral retinoblastoma cases from Tunisia and correlations with clinical features.

Postoperative Endophtalmities: therapeuthic results and Early vitrectomy.

Le carcinome basocellulaire des paupières : approche diagnostique et thérapeutique à propos de 150 cas