3,489 research outputs found
Congenital ranula
The authors describe a case of congenital ranula diagnosed by a routine prenatal ultrasonography at 21 weeks of gestation. The fetal kariotype was normal. Follow-up ultrasound scans revealed no changes in the size or the position of the cyst. Fetal growth was normal as was the amniotic fluid volume. Surgical treatment was performed 3 days after a normal vaginal delivery, with excellent results
Missense mutations at homologous positions in the fourth and fifth laminin A G-like domains of eyes shut homolog cause autosomal recessive retinitis pigmentosa
Purpose: To describe two novel mutations in the eyes shut homolog (EYS) gene in two families with autosomal recessive
retinitis pigmentosa (arRP) from Pakistan and Indonesia.
Methods: Genome-wide linkage and homozygosity mapping were performed using single nucleotide polymorphism microarray analysis in affected members of the two arRP families. Sequence analysis was performed to identify genetic changes in protein coding exons of EYS.
Results: In the Indonesian and Pakistani families, homozygous regions encompassing the EYS gene at 6q12 were identified, with maximum LOD scores of 1.8 and 3.6, respectively. Novel missense variants in the EYS gene (p.D2767Y and p.D3028Y) were found in the Pakistani and Indonesian families, respectively, that co-segregate with the disease phenotype. Interestingly, the missense variants are located at the same homologous position within the fourth and fifth laminin A G-like domains of EYS.
Conclusions: To date, mostly protein-truncating mutations have been described in EYS, while only few patients have been described with pathogenic compound heterozygous missense mutations. The mutations p.D2767Y and p.D3028Y described in this study affect highly conserved residues at homologous positions in laminin A G-like domains and support the notion that missense mutations in EYS can cause arRP
Non-stationarity Characteristics in Dynamic Vehicular ISAC Channels at 28 GHz
Integrated sensing and communications (ISAC) is a potential technology of 6G,
aiming to enable end-to-end information processing ability and native
perception capability for future communication systems. As an important part of
the ISAC application scenarios, ISAC aided vehicle-to-everything (V2X) can
improve the traffic efficiency and safety through intercommunication and
synchronous perception. It is necessary to carry out measurement,
characterization, and modeling for vehicular ISAC channels as the basic
theoretical support for system design. In this paper, dynamic vehicular ISAC
channel measurements at 28 GHz are carried out and provide data for the
characterization of non-stationarity characteristics. Based on the actual
measurements, this paper analyzes the time-varying PDPs, RMSDS and
non-stationarity characteristics of front, lower front, left and right
perception directions in a complicated V2X scenarios. The research in this
paper can enrich the investigation of vehicular ISAC channels and enable the
analysis and design of vehicular ISAC systems
Channel Measurements and Modeling for Dynamic Vehicular ISAC Scenarios at 28 GHz
Integrated sensing and communication (ISAC) is a promising technology for 6G,
with the goal of providing end-to-end information processing and inherent
perception capabilities for future communication systems. Within ISAC emerging
application scenarios, vehicular ISAC technologies have the potential to
enhance traffic efficiency and safety through integration of communication and
synchronized perception abilities. To establish a foundational theoretical
support for vehicular ISAC system design and standardization, it is necessary
to conduct channel measurements, and modeling to obtain a deep understanding of
the radio propagation. In this paper, a dynamic statistical channel model is
proposed for vehicular ISAC scenarios, incorporating Sensing Multipath
Components (S-MPCs) and Clutter Multipath Components (C-MPCs), which are
identified by the proposed tracking algorithm. Based on actual vehicular ISAC
channel measurements at 28 GHz, time-varying sensing characteristics in front,
left, and right directions are investigated. To model the dynamic evolution
process of channel, number of new S-MPCs, lifetimes, initial power and delay
positions, dynamic variations within their lifetimes, clustering, power decay,
and fading of C-MPCs are statistically characterized. Finally, the paper
provides implementation of dynamic vehicular ISAC model and validates it by
comparing key simulation statistics between measurements and simulations
Characterization of Wireless Channel Semantics: A New Paradigm
Recently, deep learning enabled semantic communications have been developed
to understand transmission content from semantic level, which realize effective
and accurate information transfer. Aiming to the vision of sixth generation
(6G) networks, wireless devices are expected to have native perception and
intelligent capabilities, which associate wireless channel with surrounding
environments from physical propagation dimension to semantic information
dimension. Inspired by these, we aim to provide a new paradigm on wireless
channel from semantic level. A channel semantic model and its characterization
framework are proposed in this paper. Specifically, a channel semantic model
composes of status semantics, behavior semantics and event semantics. Based on
actual channel measurement at 28 GHz, as well as multi-mode data, example
results of channel semantic characterization are provided and analyzed, which
exhibits reasonable and interpretable semantic information
Isolation of cellulolytic activities from Tribolium castaneum (red flour beetle)
Cellulolytic enzymes have immense potential to convert cellulosic biomass into useful products. Tribolium castaneum crude proteins were isolated to screen the cellulolytic activities. The activity was established by substrate-agar plate assay and confirmed by endoglucanase assay. Cellulolytic activitywas further purified and characterized using the different chromatographic techniques and electrophoresis. Gel filtration chromatography showed the presence of multiple forms of enzyme activities with different molecular weights. Stability of enzyme activity was investigated at differenttemperatures and pH. Optimum pH for was found 4.8 at 40oC determined as optimum temperature. Gradually decreasing Enzyme activity remained half at 60oC. Zymography and SDS-PAGE showed the presence of multiple forms of endoglucanase activities (Cel I and Cel II) with molecular weight of 55 kDaand 35 kDa
A Cluster-Based Statistical Channel Model for Integrated Sensing and Communication Channels
The emerging 6G network envisions integrated sensing and communication (ISAC)
as a promising solution to meet growing demand for native perception ability.
To optimize and evaluate ISAC systems and techniques, it is crucial to have an
accurate and realistic wireless channel model. However, some important features
of ISAC channels have not been well characterized, for example, most existing
ISAC channel models consider communication channels and sensing channels
independently, whereas ignoring correlation under the consistent environment.
Moreover, sensing channels have not been well modeled in the existing
standard-level channel models. Therefore, in order to better model ISAC
channel, a cluster-based statistical channel model is proposed in this paper,
which is based on measurements conducted at 28 GHz. In the proposed model, a
new framework based on 3GPP standard is proposed, which includes communication
clusters and sensing clusters. Clustering and tracking algorithms are used to
extract and analyze ISAC channel characteristics. Furthermore, some special
sensing cluster structures such as shared sensing cluster, newborn sensing
cluster, etc., are defined to model correlation and difference between
communication and sensing channels. Finally, accuracy of the proposed model is
validated based on measurements and simulations
Immediate latissimus dorsi pedicle flap reconstruction following the removal of an eight kilogram giant phyllodes tumour of the breast: a case report
<p>Abstract</p> <p>Introduction</p> <p>Phyllodes tumors account for less than 1% of breast tumors in women, and giant phyllodes tumors are those that are larger than 10 cm in diameter. Removal of such large tumors places a huge burden on the surgeon to reconstruct a breast that is aesthetically acceptable by the patient. We report what may be the largest giant phyllodes tumor and, most likely, the first latissimus dorsi flap used to cover such a large defect caused by the resection.</p> <p>Case presentation</p> <p>We report the case of a 36-year-old Malaysian woman who presented with a three-year history of gradually increasing swelling of the left breast, with skin changes. Examination revealed a huge, globular, lobulated mass measuring 400 mm by 350 mm. The patient had a mastectomy with an immediate latissimus dorsi pedicled myocutaneous flap reconstruction. The breast weighed 8.27 kg, and <it>ex </it><it>vivo</it>, the tumor measured 280 mm by 250 mm by 180 mm. Histopathologic analysis confirmed the diagnosis as a giant phyllodes tumor. At 12-month follow-up, the patient reports no complications and is satisfied with the aesthetic outcome.</p> <p>Conclusion</p> <p>Giant phyllodes tumors are very rare tumors that can reach up to 40 cm in diameter. Reconstruction of such a defect is a great challenge, and we report what we believe is the first latissimus dorsi flap to cover successfully a defect of approximately 400 mm by 350 mm.</p
Interaction of paraoxonase-192 polymorphism with low HDL-cholesterol in coronary artery disease risk.
A doença coronária (DC) é a principal causa
de mortalidade nos países desenvolvidos. O
aumento da peroxidação lipídica está associado
com a progressão acelerada da arteriosclerose.
A Paraoxonase (PON1) é uma
enzima antioxidante, que protege contra a
peroxidação lipídica e a DC. A actividade
da PON1 está sob controlo genético e a sua
base molecular consiste num polimorfismo
do gene da PON1 que apresenta duas isoformas
comuns: a forma nativa, Q (192 Gln)
com elevada capacidade de protecção das
LDL da peroxidação lipídica in vitro, e a
isoforma mutada R (192 Arg) com baixa
capacidade de protecção.
Objectivo: O objectivo deste trabalho foi
investigar a interacção entre o alelo R do
gene da PON 1 e os níveis plasmáticos
baixos de colesterol HDL, no risco do
aparecimento da DC.
Métodos: Participaram no estudo 818 indivíduos,
298 doentes coronários com idade
média 55.0±10.3 anos, 78.9% do sexo masculino,
e 520 controlos, com uma idade
média de 53.3±11, 7 anos, 72, 5% do sexo
masculino, tendo casos e controlos sido
emparelhados por idade e sexo. Foi considerado
um valor <de 40 mg/dl (0,90
mmol/L), nos homens e <de 50 mg/dl (1,11
mmol/L), nas mulheres como um nível baixo
de Colesterol HDL. As comparações
genotípicas, entre casos e controlos, foram efectuadas pelo teste do Chi-quadrado. A
significância estatística foi aceite para valores
de p <0,05. Para determinar o risco
relativo de DC, em relação ao genótipo RR
e aos níveis baixos de colesterol HDL, foi
usada uma análise univariada e foram utilizadas
as tabelas epidemiológicas 4x2 e
medidas de sinergismo (modelo aditivo - SI
e multiplicativo - SIM) para determinar a
interacção entre o genótipo RR e os níveis
baixos de colesterol HDL. Foi finalmente
calculado o excesso de risco relativo (RERI)
e proporção atribuída à interacção (AP).
Resultados: A PON 1 192 RR está associada
à DC [OR=1,61; p=0,043] para toda a população.
A associação de níveis baixos de
HDL com o genótipo 192 RR mostrou um
aumento do risco de DC (OR=17,38; p
<0,0001) comparada aos níveis normais de
HDL associados ao mesmo genótipo
(OR=1,39; p=0,348) e aos níveis baixos de
HDL sem o genótipo RR (OR=7,79; p
<0,0001). Índices de Sinergismo: SI= 2,3;
SIM = 1.6; RERI=9,2; AP=0,53.
Conclusão: Estes dados sugerem a existência
de um efeito sinérgico entre o genótipo
192 RR da PON1 e os valores baixos de
colesterol HDL, na emergência de DC, pois
este genótipo aumentou o risco de DC, em
especial, na população com níveis plasmáticos
baixos de colesterol HDL. A proporção
de DC que pode ser atribuída a esta interacção
(AP) foi de 0,53 significando que
53% da DC que surgiu nestes indivíduos,
foi explicada por esta interacção.INTRODUCTION:
Coronary artery disease (CAD) is the main cause of mortality in developed countries. Increased lipid peroxidation is associated with accelerated progression of atherosclerosis. Paraoxonase (PON1) is an antioxidant enzyme bound to high-density lipoprotein (HDL), which protects against lipid peroxidation and coronary artery disease. PON1 activity is under genetic control and its molecular basis is a polymorphism in the PON1 gene that shows two common isoforms: the wild Q form (192 Gln) with high ability to protect LDL from lipid peroxidation in vitro, and the mutated R (Arg) form with lower ability.
AIM:
To explore the interaction of the R allele of the paraoxonase gene and low HDL-cholesterol concentrations in CAD risk.
METHODS:
The study population consisted of 818 individuals, 298 coronary patients, aged 55.0 +/- 10.3 years, 78.9% male, and 520 age and gender matched healthy controls, aged 53.3 +/- 11.7 years, 72.5% male. Low HDL-cholesterol was defined as < 0.90 mmol/l in men and < 1.11 mmol/l in women. Comparisons of genotypes between cases and controls were performed by a chi-square test. Statistical significance was accepted at p < 0.05. Odds ratios and 95% confidence intervals for the RR genotypes and HDL-deficient subjects were computed using univariate analysis (2 x 2 tables). To determine the interaction between the RR paraoxonase genotype and HDL-deficient subjects, we used 4 x 2 epidemiologic tables and synergy measures: the additive model (Rothman's synergy index, SI) and multiplicative model (Khoury's synergy index, SIM). The relative excess risk due to interaction (RERI) and the attributable proportion (AP) due to interaction (Rothman) were calculated.
RESULTS:
The PON1 RR192 polymorphism was associated with coronary heart disease (OR = 1.61; p = 0.043) in the whole population. HDL-deficient subjects with the RR192 genotype showed increased risk for CAD (OR = 17.38; p < 0.0001) compared to those with normal HDL and RR192 (OR = 1.39; p = 0.348) and HDL-deficient subjects not carrying the RR genotype (OR = 7.79; p < 0.0001). Synergy measures were SI = 2.3, SIM = 1.6; RERI = 9.2.
CONCLUSION:
These data suggest the existence of a synergistic effect of the PON1 RR192 genotype (with lower antioxidant ability) and HDL-deficient subjects in risk for development of CAD. The AP due to this interaction was 0.53, meaning that 53% of CAD was explained by this interaction.info:eu-repo/semantics/publishedVersio
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