59 research outputs found
Recommended from our members
A new mechanistic model of critical heat flux in forced-convection subcooled boiling
Because of its practical importance and various industrial applications, the process of subcooled flow boiling has attracted a lot of attention in the research community in the past. However, the existing models are primarily phenomenological and are based on correlating experimental data rather than on a first-principle analysis of the governing physical phenomena. Even though the mechanisms leading to critical heat flux (CHF) are very complex, the recent progress in the understanding of local phenomena of multiphase flow and heat transfer, combined with the development of mathematical models and advanced Computational Fluid Dynamics (CFD) methods, makes analytical predictions of CHF quite feasible. Various mechanisms leading to CHF in subcooled boiling have been investigated. A new model for the predictions of the onset of CHF has been developed. This new model has been coupled with the overall boiling channel model, numerically implemented in the CFX 4 computer code, tested and validated against the experimental data of Hino and Ueda. The predicted critical heat flux for various channel operating conditions shows good agreement with the measurements using the aforementioned closure laws for the various local phenomena governing nucleation and bubble departure from the wall. The observed differences are consistent with typical uncertainties associated with CHF data
Primary cutaneous melanoma of the breast: A case report
which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Background: Primary cutaneous melanoma of the breast is a very rare tumour, accounting for < 5 % of all malignant melanomas. Case presentation: A young lady was seen in the breast clinic for a skin lesion in the right breast. Clinical examination and investigations confirmed a diagnosis of a primary cutaneous melanoma of the breast. The lesion was excised and the patient made good recovery. She has shown no signs of local recurrence and is under regular follow-up in the dermatology clinic. Conclusion: This case is educational as it shows that the treatment of breast cutaneous melanoma is similar to that for any skin parts with surgery remaining the main therapeutic option. It also shows that mastectomy is unnecessary as it does not improve the results obtained by wide local excision of melanoma. Background Primary cutaneous melanoma rarely affects the breast, accounting for less than 5 % of all malignant melanomas
High diagnostic rate of trio exome sequencing in consanguineous families with neurogenetic diseases.
Consanguineous marriages have a prevalence rate of 24% in Turkey. These carry an increased risk of autosomal recessive genetic conditions, leading to severe disability or premature death, with a significant health and economic burden. A definitive molecular diagnosis could not be achieved in these children previously, as infrastructures and access to sophisticated diagnostic options were limited. We studied the cause of neurogenetic disease in 246 children from 190 consanguineous families recruited in three Turkish hospitals between 2016 and 2020. All patients underwent deep phenotyping and trio whole exome sequencing, and data were integrated in advanced international bioinformatics platforms. We detected causative variants in 119 known disease genes in 72% of families. Due to overlapping phenotypes 52% of the confirmed genetic diagnoses would have been missed on targeted diagnostic gene panels. Likely pathogenic variants in 27 novel genes in 14% of the families increased the diagnostic yield to 86%. Eighty-two per cent of causative variants (141/172) were homozygous, 11 of which were detected in genes previously only associated with autosomal dominant inheritance. Eight families carried two pathogenic variants in different disease genes. De novo (9.3%), X-linked recessive (5.2%) and compound heterozygous (3.5%) variants were less frequent compared to non-consanguineous populations. This cohort provided a unique opportunity to better understand the genetic characteristics of neurogenetic diseases in a consanguineous population. Contrary to what may be expected, causative variants were often not on the longest run of homozygosity and the diagnostic yield was lower in families with the highest degree of consanguinity, due to the high number of homozygous variants in these patients. Pathway analysis highlighted that protein synthesis/degradation defects and metabolic diseases are the most common pathways underlying paediatric neurogenetic disease. In our cohort 164 families (86%) received a diagnosis, enabling prevention of transmission and targeted treatments in 24 patients (10%). We generated an important body of genomic data with lasting impacts on the health and wellbeing of consanguineous families and economic benefit for the healthcare system in Turkey and elsewhere. We demonstrate that an untargeted next generation sequencing approach is far superior to a more targeted gene panel approach, and can be performed without specialized bioinformatics knowledge by clinicians using established pipelines in populations with high rates of consanguinity
A comprehensive overview of radioguided surgery using gamma detection probe technology
The concept of radioguided surgery, which was first developed some 60 years ago, involves the use of a radiation detection probe system for the intraoperative detection of radionuclides. The use of gamma detection probe technology in radioguided surgery has tremendously expanded and has evolved into what is now considered an established discipline within the practice of surgery, revolutionizing the surgical management of many malignancies, including breast cancer, melanoma, and colorectal cancer, as well as the surgical management of parathyroid disease. The impact of radioguided surgery on the surgical management of cancer patients includes providing vital and real-time information to the surgeon regarding the location and extent of disease, as well as regarding the assessment of surgical resection margins. Additionally, it has allowed the surgeon to minimize the surgical invasiveness of many diagnostic and therapeutic procedures, while still maintaining maximum benefit to the cancer patient. In the current review, we have attempted to comprehensively evaluate the history, technical aspects, and clinical applications of radioguided surgery using gamma detection probe technology
Recommended from our members
Biallelic NAA60 variants with impaired n-terminal acetylation capacity cause autosomal recessive primary familial brain calcifications.
Primary familial brain calcification (PFBC) is characterized by calcium deposition in the brain, causing progressive movement disorders, psychiatric symptoms, and cognitive decline. PFBC is a heterogeneous disorder currently linked to variants in six different genes, but most patients remain genetically undiagnosed. Here, we identify biallelic NAA60 variants in ten individuals from seven families with autosomal recessive PFBC. The NAA60 variants lead to loss-of-function with lack of protein N-terminal (Nt)-acetylation activity. We show that the phosphate importer SLC20A2 is a substrate of NAA60 in vitro. In cells, loss of NAA60 caused reduced surface levels of SLC20A2 and a reduction in extracellular phosphate uptake. This study establishes NAA60 as a causal gene for PFBC, provides a possible biochemical explanation of its disease-causing mechanisms and underscores NAA60-mediated Nt-acetylation of transmembrane proteins as a fundamental process for healthy neurobiological functioning
Association of Helicobacter pylori positivity with the symptoms in patients with hyperemesis gravidarum
PubMedID: 23736829Purpose: To investigate the relationship between Helicobacter pylori (Hp) positivity and the severity of symptoms of nausea and vomiting in patients diagnosed with hyperemesis gravidarum (HG). Design: Prospective controlled. Methods: Ninety patients with the diagnosis of HG below the 20th week gestation, who had no additional disease and 50 pregnant women with no complaints were enrolled in the study. According to the severity of symptoms, the patients were divided into three groups as group I, II and III (mild, moderate and severe, respectively). The Rhode's scoring system was used to determine the severity of HG symptoms. HpIgG and IgM levels were determined in the blood samples and Hp DNA positivity with PCR was investigated in the saliva. Results: In accordance with the Rhode's scoring system, 15.5 % of the pregnant women had mild, 58.9 % had moderate, and 25.6 % had severe symptoms (group I, II and III, respectively). HpIgG was determined as positive in 78.6, 84.9 and 82.6 % in groups I, II and III, respectively. HpIgM positivity was determined as 26.1 % only in group III (p = 0.847). HpDNA was determined as 7.2, 3.8, and 91.3 % in group I, II, and III, respectively (p<0.01). While HpIgG was positive in 60 %, HpDNA was found to be positive in 2 % and HpIgM was found to be negative in all the pregnant women in the control group. Conclusion: A positive relationship between the symptoms of HG and Hp positivity was determined using PCR. © 2013 Springer-Verlag Berlin Heidelberg
- …