78 research outputs found
Structured population balances to support microalgae-based processes: Review of the state-of-art and perspectives analysis
Design and optimization of microalgae processes have traditionally relied on the application of unsegregated mathematical models, thus neglecting the impact of cell-to-cell heterogeneity. However, there is experimental evidence that the latter one, including but not limited to variation in mass/size, internal composition and cell cycle phase, can play a crucial role in both cultivation and downstream processes. Population balance equations (PBEs) represent a powerful approach to develop mathematical models describing the effect of cell-to-cell heterogeneity. In this work, the potential of PBEs for the analysis and design of microalgae processes are discussed. A detailed review of PBE applications to microalgae cultivation, harvesting and disruption is reported. The review is largely focused on the application of the univariate size/mass structured PBE, where the size/mass is the only internal variable used to identify the cell state. Nonetheless, the need, addressed by few studies, for additional or alternative internal variables to identify the cell cycle phase and/or provide information about the internal composition is discussed. Through the review, the limitations of previous studies are described, and areas are identified where the development of more reliable PBE models, driven by the increasing availability of single-cell experimental data, could support the understanding and purposeful exploitation of the mechanisms determining cell-to-cell heterogeneity
Laparoscopic approach for gonadectomy in pediatric patients with intersex disorders
Abstract
The birth of a child with a disorder of sex development (DSD) prompts a long-term management strategy that involves a myriad of professionals working with the family. There has been progress in diagnosis, surgical techniques and in understanding psychosocial issues related to this condition. However, since these kinds of disorders are rare and have many anatomical variations, individual care is necessary, especially regarding surgical management. Gonadectomy is indicated in a number of intersex disorders with a Y chromosome to reduce the associated risk of cancer. Recently, laparoscopy has gained wide acceptance in pediatric urology. Laparoscopy is also reported to be a useful tool for diagnosing and treating DSD because of its minimal invasiveness and favorable cosmetic outcome. However, reports of evaluation and management using laparoscopy for large numbers of DSD patients are limited and debate is still open about indications and timing of gonadectomy. In this study, we reviewed the literature of the last 10 years about the role of laparoscopic gonadectomy in patients with DSD. In the analyzed papers, all the procedures were accomplished successfully using laparoscopy. No conversions to open surgery neither intra-operative complications were reported in all series. Post-operative complications were reported only in one series and included 1 umbilical port infection [2% (1/50)] and 1 pelvic abscess [2% (1/50)], both treated with antibiotic therapy (grade I Clavien-Dindo). Of the analyzed series, 7/10 reported postoperative diagnosis of gonadal tumors. The histopathologic examinations revealed 15 cases of gonadoblastoma, 7 cases of dysgerminoma and 2 cases of seminoma. Analyzing the single series, the incidence of these tumors varied between 10% and 33%. The results of our review confirmed the safety and efficacy of laparoscopic gonadectomy in DSD patients. In our mind, laparoscopic gonadectomy should be accepted as the treatment of choice in children and adolescents with these rare conditions. It thereby eliminates the risk of malignancies of gonadal origin with the advantages of a minimally invasive procedure, with lower morbidity, quicker postoperative recovery and excellent cosmetic results
Pseudomonas aeruginosa in a neonatal intensive care unit: molecular epidemiology and infection control measures
<p>Abstract</p> <p>Background</p> <p><it>Pseudomonas aeruginosa</it>, a non-fermentative, gram-negative rod, is responsible for a wide variety of clinical syndromes in NICU patients, including sepsis, pneumonia, meningitis, diarrhea, conjunctivitis and skin infections. An increased number of infections and colonisations by <it>P. aeruginosa </it>has been observed in the neonatal intensive care unit (NICU) of our university hospital between 2005 and 2007.</p> <p>Methods</p> <p>Hand disinfection compliance before and after an educational programme on hand hygiene was evaluated. Identification of microrganisms was performed using conventional methods. Antibiotic susceptibility was evaluated by MIC microdilution. Genotyping was performed by PFGE analysis.</p> <p>Results</p> <p>The molecular epidemiology of <it>Pseudomonas aeruginosa </it>in the NICU of the Federico II University hospital (Naples, Italy) and the infection control measures adopted to stop the spreading of <it>P. aeruginosa </it>in the ward were described. From July 2005 to June 2007, <it>P. aeruginosa </it>was isolated from 135 neonates and caused severe infections in 11 of them. Macrorestriction analysis of clinical isolates from 90 neonates identified 20 distinct genotypes, one major PFGE type (A) being isolated from 48 patients and responsible for 4 infections in 4 of them, four other distinct recurrent genotypes being isolated in 6 to 4 patients. Seven environmental strains were isolated from the hand of a nurse and from three sinks on two occasions, two of these showing PFGE profiles A and G identical to two clinical isolates responsible for infection. The successful control of the outbreak was achieved through implementation of active surveillance of healthcare-associated infections in the ward together with environmental microbiological sampling and an intense educational programme on hand disinfection among the staff members.</p> <p>Conclusion</p> <p><it>P. aeruginosa </it>infections in the NICU were caused by the cross-transmission of an epidemic clone in 4 neonates, and by the selection of sporadic clones in 7 others. An infection control programme that included active surveillance and strict adherence to hand disinfection policies was effective in controlling NICU-acquired infections and colonisations caused by <it>P. aeruginosa</it>.</p
Effects of dopaminergic treatment on inhibitory control differ across Hoehn and Yahr stages of Parkinson's disease
: Motor inhibitory control, a core component of cognitive control, is impaired in Parkinson's disease, dramatically impacting patients' abilities to implement goal-oriented adaptive strategies. A progressive loss of the midbrain's dopamine neurons characterizes Parkinson's disease and causes motor features responsive to dopaminergic treatments. Although such treatments restore motor symptoms, their impact on response inhibition is controversial. Most studies failed to show any effect of dopaminergic medicaments, although three studies found that these drugs selectively improved inhibitory control in early-stage patients. Importantly, all previous studies assessed only one domain of motor inhibition, i.e. reactive inhibition (the ability to react to a stop signal). The other domain, i.e. proactive inhibition (the ability to modulate reactive inhibition pre-emptively according to the current context), was utterly neglected. To re-examine this issue, we recruited cognitively unimpaired Parkinson's patients under dopaminergic treatment in the early (Hoehn and Yahr, 1-1.5, n = 20), intermediate (Hoehn and Yahr 2, n = 20), and moderate/advanced (Hoehn and Yahr, 2.5-3, n = 20) stages of the disease. Using a cross-sectional study design, we compared their performance on a simple reaction-time task and a stop-signal task randomly performed twice on dopaminergic medication (ON) and after medication withdrawal (OFF). Normative data were collected on 30 healthy controls. Results suggest that medication effects are stage-dependent. In Hoehn and Yahr 1-1.5 patients, drugs selectively impair reactive inhibition, leaving proactive inhibition unaffected. In the ON state, Hoehn and Yahr two patients experienced impaired proactive inhibition, whereas reactive inhibition is no longer affected, as it deteriorates even during the OFF state. By contrast, Hoehn and Yahr 2.5-3 patients exhibited less efficient reactive and proactive inhibition in the OFF state, and medication slightly improved proactive inhibition. This evidence aligns with the dopamine overdose hypothesis, indicating that drug administration may overdose intact dopamine circuitry in the earliest stages, impairing associated cognitive functions. In later stages, the progressive degeneration of dopaminergic neurons prevents the overdose and can exert some beneficial effects. Thus, our findings suggest that inhibitory control assessment might help tailor pharmacological therapy across the disease stage to enhance Parkinson's disease patients' quality of life by minimizing the hampering of inhibitory control and maximizing the reduction of motor symptoms
Surgical management of pediatric vesicoureteral reflux: A comparative study between endoscopic, laparoscopic, and open surgery
Our retrospective study compared the results of three surgical procedures for correction of pediatric vesicoureteral reflux (VUR): open Cohen, laparoscopic Lich-Gregoir reimplantation (LEVUR), and endoscopic subureteric injection (STING) procedure.
METHODS:
We analyzed 90 patients (50 girls, 40 boys, average age 4.86 years) operated in two centers of pediatric surgery for VUR. Exclusion criteria were Grade 1 VUR, Grade 5 VUR with megaureters requiring ureteral tapering, secondary VUR, and patients already operated for VUR. Thirty patients underwent Cohen, 30 LEVUR, and 30 STING procedure. Follow-up included renal ultrasonography and voiding cystourethrography 6 months postoperatively. The statistical analysis was performed using χ(2) Pearson and Fisher tests.
RESULTS:
Operative time was shorter using STING either for unilateral or bilateral correction (P = .001). Hospitalization was statistically shorter using STING and LEVUR compared to Cohen (P = .001). The pain scores were worse after Cohen (P = .001). Analgesic requirements were higher after Cohen (P = .001). Reflux persistence was higher after STING (10 cases versus 5 Cohen and 4 LEVUR). Cohen presented more complications compared to LEVUR and STING (P = .001). Intraoperative costs were higher for STING procedure (P = .001), while hospitalization costs were significantly higher for Cohen procedure (P = .001).
CONCLUSIONS:
In children affected by VUR, open Cohen and LEVUR reported a higher success rate than STING procedure. However, Cohen procedure had a very long and painful hospital stay, more complications, more analgesic requirements compared to STING and LEVUR. Comparing the three techniques, it seems that LEVUR presents a high success rate similar to the Cohen procedure, but in addition, it presents the same advantages of STING procedure with no postoperative pain and a lower postoperative morbidity
Thyroid autoimmunity, thyroglobulin autoantibodies and thyroid cancer prognosis
Relevance of thyroid autoimmunity to prognosis of papillary thyroid carcinoma is still unsettled. We decided to investigate the impact of thyroid autoimmunity on prognosis of papillary thyroid carcinoma and the handling of TgAbs. We evaluated the clinical course of a large group of patients according to the presence (PTC-LT) or absence (PTC) of lymphocytic thyroiditis at histology. We studied 194 consecutive patients with a diagnosis of PTC and treated with total thyroidectomy plus ¹³¹I ablation between 2007 and 2009. Median follow-up (with 25th-75th percentiles) was 84·0 (56·4-118·0) months. The remission criteria were: basal Tg <0·2 ng/mL (or stimulated Tg <1), TgAbs <8 IU/mL (otherwise "decreasing TgAb trend", a decline of ≥20% in sequential TgAb measurements) and unremarkable imaging. PTC-LT and PTC patients had comparable treatment.TgAbs were detectable in 72·5% of PTC-LT and 16·5% of PTC patients. Time to remission was longer in the detectable than in the undetectable TgAb cohort (28·5 vs· 7·5 months [median]; HR 0·54, CI 0·35-0·83, p=0·005). When comparing PTC-LT to PTC patients the difference was maintained in the detectable TgAb (29·3 vs 13·0 months; HR 0·38, CI 0·18-0·80; p=0·01), but not in the undetectable TgAb cohort (7·7 vs 7·3 months; HR 0·90, CI 0·55-1·47; p=0·68). Using the decreasing TgAb trend, the influence of detectable TgAbs on time to remission was abolished. Thyroid autoimmunity does not influence the prognosis of papillary thyroid carcinoma. A decreasing TgAb trend seems an appropriate criterion to establish the remission of papillary thyroid carcinoma
Engineering strategies of microalgal cultivation for potential jet fuel production – A critical review
The aviation industry stands as a well-known "hard to electrify" sector, currently responsible for the consumption of massive amounts of fossil fuels, considerably contributing to global CO2 emissions. The need to reduce the aviation carbon footprint to comply with the European Green Deal objectives, has driven intensive research into the so-called bio-jet fuels (BJF) that can be obtained from different lipid-rich substrates, including microalgae among the most promising. Starting from the analysis of existing studies dealing with the selection of the strains more indicated for BJF production, this review examines the most recent breakthrough in microalgae cultivation techniques and lipid accumulation strategies, focusing on the approaches targeting the enhancement of the process environmental sustainability. The main bottlenecks in each phase of the production process are identified and critically reviewed. The most recent solutions are also thoroughly discussed to point out room for improvements in consolidated engineering strategies, as well as areas of further scientific research to advance the state of the art on micro-algal potential for BJF production
Efficacy of very low-calorie ketogenic diet with the Pronokal® method in obese women with polycystic ovary syndrome: a 16-week randomized controlled trial
Objective: The aim of this study isto assess the efficacy of a very low-calorie ketogenic diet (VLCKD) method vs a Mediterranean low-calorie diet (LCD) in obese polycystic ovary syndrome (PCOS) women of a reproductive age.Design: Randomized controlled open-label trial was performed in this study. The treatment period was 16 weeks; VLCKD for 8 weeks then LCD for 8 weeks, according to the Pronokal (R) method (experimental group; n = 15) vs Mediterranean LCD for 16 weeks (control group; n = 15). Ovulation monitoring was carried out at baseline and after 16 weeks, while a clinical exam, bioelectrical impedance analysis (BIA), anthropometry, and biochemical analyses were performed at baseline, at week 8, and at week 16.Results: BMI decreased significantly in both groups and to a major extent in the experimental group (-13.7% vs -5.1%, P = 0.0003). Significant differences between the experimental and the control groups were also observed in the reduction of waist circumference (-11.4% vs -2.9%), BIA-measured body fat (-24.0% vs -8.1%), and free testosterone (-30.4% vs -12.6%) after 16 weeks (P = 0.0008, P = 0.0176, and P = 0.0009, respectively). Homeostatic model assessment for insulin resistance significantly decreased only in the experimental group (P = 0.0238) but without significant differences with respect to the control group (-23% vs -13.2%, P > 0.05). At baseline, 38.5% of participants in the experimental group and 14.3% of participants in the control group had ovulation, which increased to 84.6% (P = 0.031) and 35.7% (P > 0.05) at the end of the study, respectively.Conclusion: In obese PCOS patients, 16 weeks of VLCKD protocol with the Pronokal (R) method was more effective than Mediterranean LCD in reducing total and visceral fat, and in ameliorating hyperandrogenism and ovulatory dysfunction.Significance statements: To the best of our knowledge, this is the first randomized controlled trial on the use of the VLCKD method in obese PCOS. It demonstrates the superiority of VLCKD with respect to Mediterranean LCD in reducing BMI with an almost selective reduction of fat mass and a unique effect of VLCKD in reducing visceral adiposity, insulin resistance, and in increasing SHBG with a consequent reduction of free testosterone. Interestingly, this study also demonstrates the superiority of the VLCKD protocol in improving ovulation, whose occurrence increased by 46.1% in the group treated by the VLCKD method against a rise of 21.4% in the group treated by Mediterranean LCD. This study extends the therapeutic approach possibilities in obese PCOS women
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