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1.
Plant Cell Environ ; 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39163322

RESUMEN

Cortical lacunae caused by drought, especially observed in hybrids originating from Vitis rupestris, disrupt the connection between roots and soil. Yet, the physiological processes behind lacuna formation during drought and its consistency across Vitis species remain unclear. Here, we used a root pressure probe to investigate fine root hydraulic and mechanical properties, in the arid-adapted R-65 and drought-susceptible 101-14Mgt cultivars. We then performed P-V curves, root sap osmolality, and electrolyte leakage (EL) and used fluorescent light microscopy techniques. Only 101-14Mgt showed lacunae formation during drought due to its stiffer cortical tissue, unlike R-65. Lacunae resulted in a notable decline in root hydraulic conductivity during severe drought, with increased EL and root sap osmolality, indicating potential cellular damage. R-65 displayed different and xerophyte-like characteristics featuring a higher turgor loss point and decreased root capacitance, essential for maintaining root structural integrity in arid conditions. Our findings highlight lacuna formation is impacted by root tissue elasticity possibly linked to specific Vitis species favoring deeper rooting. In arid-adapted grapevines, hydraulic regulators such as reduced turgor loss point, and root capacitance could contribute to enhanced drought tolerance.

2.
BMC Med Res Methodol ; 24(1): 201, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39266975

RESUMEN

BACKGROUND: Clinical trials play a crucial role in biomedical research, and it is important to register them in public registries to ensure transparency and prevent research waste. In this study, we wished to determine what steps need to be taken to identify every clinical trial run in India that has been registered in any of the (non-Indian) World Health Organization-recognised primary registries. Of the 16 registries, we studied all except that of the European Union, which will be studied separately. METHODS: Two methodologies were employed for each registry, except for four that did not facilitate one or the other method. Methodology A involved downloading all the records in a registry and querying them. Methodology B involved conducting a search via the registry website. RESULTS: Only four registries provided consistent results with both methodologies. Seven registries had different results from the two methodologies. Of these, in four cases, in Methodology A one field indicated that the study ran in India, while another indicated otherwise. CONCLUSIONS: The above-mentioned ambiguities should be addressed by the concerned registries. Overall, this study reinforces the need for improved data accuracy and transparency in clinical trial registries and emphasizes the importance of resolving complications faced by users while navigating the registries. Ensuring accurate and comprehensive registration of clinical trials is essential for meta-research and the use of such data by a variety of stakeholders.


Asunto(s)
Ensayos Clínicos como Asunto , Sistema de Registros , Sistema de Registros/estadística & datos numéricos , India , Humanos , Ensayos Clínicos como Asunto/métodos , Ensayos Clínicos como Asunto/estadística & datos numéricos , Ensayos Clínicos como Asunto/normas , Estudios Transversales , Investigación Biomédica/estadística & datos numéricos , Investigación Biomédica/métodos , Investigación Biomédica/normas , Exactitud de los Datos
3.
Clin Oral Implants Res ; 35(9): 1151-1162, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38847078

RESUMEN

OBJECTIVES: The incorporation of retromolar bone grafts used for alveolar ridge augmentation is not well understood. This prospective observational study aims to supply histomorphometrical data from bone graft biopsies taken at the time of retrieval and after a 3-month healing period using patient-matched biopsies. MATERIALS AND METHODS: In 17 patients, trephine biopsies of the graft were acquired at the time of graft retrieval and after a 3-month healing period. The biopsies were compared histomorphometrically regarding the number of osteocytes, appearance of osteocyte lacunae, quantity, surface area, and activity of the Haversian canals. RESULTS: All grafts appeared clinically stable after screw removal and 17 implants were placed. Histomorphometric analysis revealed no significant difference in the number of osteocytes (p = .413), osteocyte lacunae (p = .611), the ratio of filled/empty osteocyte lacunae (p = .467) and active Haversian canals (p = .495) between the biopsies retrieved after a 3-months healing period with those at the time of grafting. The only significant difference was noted in the mean surface area of the Haversian canals (p = .002). Specifically, the grafts post 3-month healing showed a significantly larger mean area (0.069 mm2) compared to the time of grafting (0.029 mm2). CONCLUSION: This study demonstrates, compared to other data, a high rate of vital structures in retromolar bone block grafts after 3 months of healing, exhibiting the same histological features in comparison to the biopsies from the native alveolar ridge. Standard histomorphometrical parameters, e.g., the amount of filled or empty osteocyte lacunae for the description of the vitality of the graft need to be reappraised.


Asunto(s)
Aumento de la Cresta Alveolar , Trasplante Óseo , Osteocitos , Humanos , Estudios Prospectivos , Aumento de la Cresta Alveolar/métodos , Masculino , Femenino , Persona de Mediana Edad , Biopsia , Adulto , Trasplante Óseo/métodos , Osteocitos/patología , Cicatrización de Heridas/fisiología , Anciano , Implantación Dental Endoósea/métodos , Resultado del Tratamiento
4.
BMC Ophthalmol ; 24(1): 372, 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39187757

RESUMEN

BACKGROUND: Microcephaly with or without chorioretinopathy, lymphedema, or mental retardation is a rare autosomal dominant disease caused by mutations in KIF11 which disrupt EG5 protein function, impacting the development and maintenance of retinal and lymphatic structures due to its expression in the retinal photoreceptor cilia. The primary ocular finding in MCLMR is chorioretinopathy. Additional features can include microphthalmia, angle-closure glaucoma, persistent hyperplastic primary vitreous, cataract, pseudo-coloboma, persistent hyaloid artery, and myopic or hypermetropic astigmatism. The appearance of the chorioretinal lesions as white to pinkish, round, non-elevated atrophic areas devoid of blood vessels resembles the lacunae in Aicardy syndrome. Due to the lack of systematic description of the lesions and significant phenotypical variability, there is an impending need for a detailed report of each case. CASE PRESENTATION: A child with microcephaly detected in the third trimester of gestation began her following in the ophthalmology department due to a non-visually significant cataract. Shortly after, she developed nystagmus and large-angle alternating esotropia with cross-fixation. Her fundus initially showed a pallid optic disc and pigmentary changes, developing thereafter retinal lacunae and a retinal fold. Her differential diagnosis accompanied the dynamic changes in her fundus, which included congenital infections, Leber´s Congenital Amaurosis and Aicardy syndrome. At 19 months old, genetic testing identified a heterozygous mutation (c.1159 C > T, p.Arg387*) in the KIF11 gene. The patient underwent bilateral medial rectus muscle recession surgery at 2 years old for persistent esotropia, with significant improvement. Refraction revealed a hyperopic astigmatism in both eyes (+ 0.25 -2.50 × 180 OD and + 0.75 -2.00 × 170 OS). She continues to require right eye patching for 2 hours daily. CONCLUSIONS: This case report expands the phenotypic spectrum of MCLMR by demonstrating a unique combination of retinal features which sheds new light on differential diagnosis from Aicardy syndrome. Our findings emphasize the significant phenotypic variability associated with MCLMR, particularly regarding ocular involvement. This underscores the importance of detailed clinical evaluation and comprehensive reporting of cases to improve our understanding of the disease spectrum and genotype-phenotype correlations.


Asunto(s)
Discapacidad Intelectual , Linfedema , Microcefalia , Humanos , Microcefalia/genética , Microcefalia/diagnóstico , Femenino , Linfedema/genética , Linfedema/diagnóstico , Discapacidad Intelectual/genética , Discapacidad Intelectual/diagnóstico , Enfermedades de la Retina/diagnóstico , Enfermedades de la Retina/genética , Displasia Retiniana , Cinesinas , Facies
5.
Arch Microbiol ; 205(8): 294, 2023 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-37480395

RESUMEN

A novel motile bacterium was isolated from a sediment sample collected in Kochi backwaters, Kerala, India. This bacterium is Gram negative, rod shaped, 1.0-1.5 µm wide, and 2.0-3.0 µm long. It was designated as strain AK27T. Colonies were grown on marine agar displayed circular, off-white, shiny, moist, translucent, flat, margin entire, 1-2 mm in diameter. The major fatty acids identified in this strain were C18:1 ω7c, C16:0, and summed in feature 3. The composition of polar lipids in the strain AK27T included phosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol, one unidentified amino lipid, two unidentified aminophospholipids, two unidentified phospholipids, and six unidentified lipids. The genomic DNA of strain AK27T exhibited a G+C content of 56.4 mol%. Based on the analysis of 16S rRNA gene sequence, strain AK27T showed sequence similarity to M. ramblicola D7T and M. zhoushanense WM3T as 98.99% and 98.58%, respectively. Compared to other type strains of the Marinobacterium genus, strain AK27T exhibited sequence similarities ranging from 91.7% to 96.4%. When compared to Marinobacterium zhoushanense WM3T and Marinobacterium ramblicola D7T, strain AK27T exhibited average nucleotide identity values of 80.25% and 79.97%, and dDDH values of 22.9% and 22.6%, respectively. The genome size of the strain AK27T was 4.55 Mb, with 4,229 coding sequences. Based on the observed phenotypic and chemotaxonomic features, and the results of phylogenetic and phylogenomic analysis, this study proposes the classification of strain AK27T as a novel species within the genus Marinobacterium. The proposed name for this novel species is Marinobacterium lacunae sp. nov.


Asunto(s)
Alteromonadaceae , Filogenia , ARN Ribosómico 16S/genética , Agar , Cardiolipinas
6.
J Biomech Eng ; 145(6)2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-36629002

RESUMEN

Physiological and pathological processes such as aging, diseases, treatments, and lactation can alter lacunar-canalicular network (LCN) morphology and perilacunar region properties. These modifications can impact the mechanical environment of osteocytes which in turn can influence osteocyte mechanosensitivity and the remodeling process. In this study, we aim to evaluate how the modifications in the canalicular morphology, lacunar density, and the perilacunar region properties influence the local mechanical environment of LCN and the apparent bone properties using three-dimensional finite element (FE) modeling. The simulation results showed that a 50% reduction in perilacunar elastic modulus led to about 7% decrease in apparent elastic modulus of the bone. The increase in canalicular density, length, and diameter did not influence the strain amplification in the models but they increased the amount of highly strained bone around LCN. Change in lacunar density did not influence the strain amplification and the amount of highly strained regions on LCN surfaces. Reduction in perilacunar elastic modulus increased both the strain amplification and the volume of highly strained tissue around and on the surface of LCN. The FE models of LCN in this study can be utilized to quantify the influence of modifications in canalicular morphology, lacunar density, and perilacunar region properties on the apparent bone properties and the local mechanical environment of LCN. Although this is a numerical study with idealized models, it provides important information on how mechanical environment of osteocytes is influenced by the modifications in LCN morphology and perilacunar region properties due to physiological and pathological processes.


Asunto(s)
Huesos , Osteocitos , Femenino , Humanos , Análisis de Elementos Finitos , Simulación por Computador
7.
Int J Mol Sci ; 24(23)2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-38069332

RESUMEN

Osteogenesis imperfecta (OI) is a rare congenital bone dysplasia generally caused by a mutation of one of the type I collagen genes and characterized by low bone mass, numerous fractures, and bone deformities. The collagen organization and osteocyte lacuna arrangement were investigated in the long bones of 17-week-old wildtype (WT, n = 17) and osteogenesis imperfecta mice (OIM, n = 16) that is a validated model of severe human OI in order to assess their possible role in bone fragility. Fractures were counted after in vivo scanning at weeks 5, 11, and 17. Humerus, femur, and tibia diaphyses from both groups were analyzed ex vivo with pQCT, polarized and ordinary light histology, and Nano-CT. The fractures observed in the OIM were more numerous in the humerus and femur than in the tibia, whereas the quantitative bone parameters were altered in different ways among these bones. Collagen fiber organization appeared disrupted, with a lower birefringence in OIM than WT bones, whereas the osteocyte lacunae were more numerous, more spherical, and not aligned in a lamellar pattern. These modifications, which are typical of immature and less mechanically competent bone, attest to the reciprocal alteration of collagen matrix and osteocyte lacuna organization in the OIM, thereby contributing to bone fragility.


Asunto(s)
Fracturas Óseas , Osteogénesis Imperfecta , Animales , Humanos , Ratones , Huesos/diagnóstico por imagen , Huesos/patología , Colágeno/genética , Modelos Animales de Enfermedad , Fracturas Óseas/genética , Mutación , Osteogénesis/genética , Osteogénesis Imperfecta/genética , Osteogénesis Imperfecta/patología
8.
Mater Des ; 231: 112087, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37323219

RESUMEN

While advanced imaging strategies have improved the diagnosis of bone-related pathologies, early signs of bone alterations remain difficult to detect. The Covid-19 pandemic has brought attention to the need for a better understanding of bone micro-scale toughening and weakening phenomena. This study used an artificial intelligence-based tool to automatically investigate and validate four clinical hypotheses by examining osteocyte lacunae on a large scale with synchrotron image-guided failure assessment. The findings indicate that trabecular bone features exhibit intrinsic variability related to external loading, micro-scale bone characteristics affect fracture initiation and propagation, osteoporosis signs can be detected at the micro-scale through changes in osteocyte lacunar features, and Covid-19 worsens micro-scale porosities in a statistically significant manner similar to the osteoporotic condition. Incorporating these findings with existing clinical and diagnostic tools could prevent micro-scale damages from progressing into critical fractures.

9.
Calcif Tissue Int ; 111(4): 430-444, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35618777

RESUMEN

Osteopetrosis is a heterogeneous group of rare hereditary diseases characterized by increased bone mass of poor quality. Autosomal-dominant osteopetrosis type II (ADOII) is most often caused by mutation of the CLCN7 gene leading to impaired bone resorption. Autosomal recessive osteopetrosis (ARO) is a more severe form and is frequently accompanied by additional morbidities. We report an adult male presenting with classical clinical and radiological features of ADOII. Genetic analyses showed no amino-acid-converting mutation in CLCN7 but an apparent haploinsufficiency and suppression of CLCN7 mRNA levels in peripheral blood mononuclear cells. Next generation sequencing revealed low-frequency intronic homozygous variations in CLCN7, suggesting recessive inheritance. In silico analysis of an intronic duplication c.595-120_595-86dup revealed additional binding sites for Serine- and Arginine-rich Splicing Factors (SRSF), which is predicted to impair CLCN7 expression. Quantitative backscattered electron imaging and histomorphometric analyses revealed bone tissue and material abnormalities. Giant osteoclasts were present and additionally to lamellar bone, and abundant woven bone and mineralized cartilage were observed, together with increased frequency and thickness of cement lines. Bone mineralization density distribution (BMDD) analysis revealed markedly increased average mineral content of the dense bone (CaMean T-score + 10.1) and frequency of bone with highest mineral content (CaHigh T-score + 19.6), suggesting continued mineral accumulation and lack of bone remodelling. Osteocyte lacunae sections (OLS) characteristics were unremarkable except for an unusually circular shape. Together, our findings suggest that the reduced expression of CLCN7 mRNA in osteoclasts, and possibly also osteocytes, causes poorly remodelled bone with abnormal bone matrix with high mineral content. This together with the lack of adequate bone repair mechanisms makes the material brittle and prone to fracture. While the skeletal phenotype and medical history were suggestive of ADOII, genetic analysis revealed that this is a possible mild case of ARO due to deep intronic mutation.


Asunto(s)
Canales de Cloruro , Osteopetrosis , Canales de Cloruro/genética , Homocigoto , Humanos , Leucocitos Mononucleares/metabolismo , Masculino , Mutación , Osteopetrosis/diagnóstico , Osteopetrosis/genética , Osteopetrosis/metabolismo , Fenotipo , ARN Mensajero
10.
Am J Obstet Gynecol ; 227(3): 384-391, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35248577

RESUMEN

Placenta accreta has been described as a spectrum of abnormal attachment of villous tissue to the uterine wall, ranging from superficial attachment to the inner myometrium without interposing decidua to transmural invasion through the entire uterine wall and beyond. These descriptions have prevailed for more than 50 years and form the basis for the diagnosis and grading of accreta placentation. Accreta placentation is essentially the consequence of uterine remodeling after surgery, primarily after cesarean delivery. Large cesarean scar defects in the lower uterine segment are associated with failure of normal decidualization and loss of the subdecidual myometrium. These changes allow the placental anchoring villi to implant, and extravillous trophoblast cells to migrate, close to the serosal surface of the uterus. These microscopic features are central to the misconception that the accreta placental villous tissue is excessively invasive and have led to much confusion and heterogeneity in clinical data. Progressive recruitment of large arteries in the uterine wall, that is, helicine, arcuate, and/or radial arteries, results in high-velocity maternal blood entering the intervillous space from the first trimester of pregnancy and subsequent formation of placental lacunae. Recently, guided sampling of accreta areas at delivery has enabled accurate correlation of prenatal imaging data with intraoperative features and histopathologic findings. In more than 70% of samples, there were thick fibrinoid depositions between the tip of most anchoring villi and the underlying uterine wall and around all deeply implanted villi. The distortion of the uteroplacental interface by these dense depositions and the loss of the normal plane of separation are the main factors leading to abnormal placental attachment. These data challenged the classical concept that placenta accreta is simply owing to villous tissue sitting atop the superficial myometrium without interposed decidua. Moreover, there is no evidence in accreta placentation that the extravillous trophoblast is abnormally invasive or that villous tissue can cross the uterine serosa into the pelvis. It is the size of the scar defect, the amount of placental tissue developing inside the scar, and the residual myometrial thickness in the scar area that determine the distance between the placental basal plate and the uterine serosa and thus the risk of accreta placentation.


Asunto(s)
Placenta Accreta , Cicatriz/patología , Femenino , Humanos , Miometrio/patología , Placenta/irrigación sanguínea , Placenta Accreta/etiología , Placenta Accreta/patología , Placentación , Embarazo
11.
Curr Oncol Rep ; 24(5): 603-610, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35199295

RESUMEN

PURPOSE OF REVIEW: This review will discuss micropapillary urothelial carcinoma with respect to biology, histopathologic characteristics, genetic and molecular features, diagnosis, clinical management, and future directions of research. RECENT FINDINGS: Recent consensus opinion study showed only moderate interobserver reproducibility in the diagnostic criteria. The most reproducible criteria with the highest consensus were multiple nests in the same lacunar spaces. There are recent reports of high rates of intratumoral heterogeneity of ERBB2 amplification within tumor containing both micropapillary and classic urothelial components. Micropapillary urothelial carcinoma is a well-documented highly aggressive variant of urothelial carcinoma with proven worse outcomes. Accurate recognition and reporting of this pattern is critical for optimal management. Newer therapeutic strategies related to the molecular and genetic findings seen in MPUC remain to be explored further.


Asunto(s)
Carcinoma Papilar , Carcinoma de Células Transicionales , Neoplasias de la Vejiga Urinaria , Carcinoma Papilar/genética , Carcinoma Papilar/patología , Carcinoma de Células Transicionales/genética , Carcinoma de Células Transicionales/patología , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/patología , Urotelio/patología
12.
Ultrasound Obstet Gynecol ; 59(4): 457-464, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34837427

RESUMEN

OBJECTIVE: Low-implantation pregnancy (LIP) is an important marker for the diagnosis of placenta accreta spectrum (PAS) in the first trimester. Many grayscale and color Doppler ultrasound markers of PAS have been defined in the second and third trimesters of pregnancy, but have not been studied in the first trimester. The aim of this study was to determine whether PAS sonographic markers could be used in the first trimester to differentiate patients with LIP who develop PAS from those who do not. METHODS: This was a retrospective case-control study of women who delivered at our institution between 2009 and 2019. Cases were women with PAS who delivered by Cesarean hysterectomy and who had undergone first-trimester ultrasound demonstrating LIP. Controls were women with persistent placenta previa without PAS who delivered by Cesarean section without postpartum hemorrhage and who had undergone first-trimester ultrasound demonstrating LIP. Sonographic images were reviewed by an investigator blinded to pregnancy outcome and ultrasound reports. Images were reviewed for presence of abnormal uteroplacental interface, increased lower uterine segment hypervascularity and placental lacunae, with or without swirling on grayscale or color Doppler ultrasound. RESULTS: Following review of the electronic health records, 21 cases and 46 controls met the inclusion criteria. Placental lacunae were present in 18/21 (85.7%) cases and 7/46 (15.2%) controls (odds ratio (OR), 33.4; 95% CI, 7.7-144.4; P < 0.001). The number of lacunae was significantly higher in cases compared with controls, with a median of five lacunae present in cases compared with a median of one lacuna in controls (P < 0.001). The median size of the lacunae was also significantly larger in cases compared with controls, measuring 10.03 (interquartile range (IQR), 7.3-12.05) mm and 4.15 (IQR, 4.05-5.05) mm, respectively (P = 0.001). Lacunae swirling on grayscale or color Doppler ultrasound was noted only in PAS cases, with 10/12 (83.3%) having swirling on grayscale ultrasound and 12/12 (100%) having swirling on color Doppler (P < 0.001). Presence of an abnormal uteroplacental interface was also observed only in PAS cases, at a rate of 17/20 (85.0%) (P < 0.001). Lower uterine segment (uterovesical, subplacental and/or intraplacental) hypervascularity was present in 14/14 (100%) cases and only 1/12 (8.3%) controls (P < 0.001). CONCLUSION: In women at risk of PAS, ultrasound markers of PAS can and should be assessed as early as in the first trimester. The use of a first-trimester prenatal ultrasound screening protocol and standardized approach to ultrasound examination in at-risk mothers may help increase detection of PAS and enable planning for optimal management of affected pregnancies. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Placenta Accreta , Estudios de Casos y Controles , Cesárea , Femenino , Humanos , Placenta/diagnóstico por imagen , Placenta Accreta/diagnóstico por imagen , Embarazo , Resultado del Embarazo , Primer Trimestre del Embarazo , Estudios Retrospectivos , Ultrasonografía Prenatal/métodos
13.
J Musculoskelet Neuronal Interact ; 22(3): 305-315, 2022 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-36046986

RESUMEN

OBJECTIVES: Patients with type-2 diabetes mellitus (T2DM) have increased risk for bone fractures which points towards impaired bone quality. METHODS: We measured bone mineralization density distribution (BMDD) and osteocyte lacunae section (OLS) characteristics based on quantitative backscattered electron images of transiliac biopsy samples from n=26 premenopausal women with T2DM. Outcomes were compared to those from reference cohorts as well as between T2DM subgroups defined by clinical characteristics. RESULTS: Comparison to references did not reveal any differences in BMDD (all p>0.05) but a lowered OLS-density in cancellous bone in T2DM (-14.9%, p<0.001). Neither BMDD nor OLS-characteristics differed in T2DM subgroups defined by HbA1c (<7% versus >7%). The average degree of bone mineralization (CaMean) was higher (0.44 wt%Ca in T2DM, 0.30 wt%Ca in reference) and consistently the calcium concentration between the tetracycline double labels (CaYoung) was higher (0.76 wt%Ca, all p<0.001) in cancellous versus cortical bone. CONCLUSIONS: Our findings suggest that bone matrix mineralization was neither affected by the presence nor by the glycemic control of T2DM in our study cohort. The intra-individual differences between cancellous and cortical bone mineralization gave evidence for differences in the time course of the early mineralization process in these compartments in general.


Asunto(s)
Diabetes Mellitus Tipo 2 , Densidad Ósea , Huesos , Calcificación Fisiológica , Femenino , Humanos , Premenopausia
14.
J Fish Biol ; 100(5): 1205-1213, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35194781

RESUMEN

Recent comparative studies of billfishes (Istiophoridae and Xiphiidae) have provided evidence of differences in the form and function of the rostra (bill) among species. Here, we report the discovery of a new structure, lacuna rostralis, on the rostra of sailfish Istiophorus platypterus, which is absent on the rostra of swordfish Xiphias gladius, striped marlin Kajikia audax and blue marlin Makaira nigricans. The lacunae rostralis are small cavities that contain teeth. They were found on the ventral rostrum surface of all I. platypterus specimens examined and dorsally in half of them. Ventrally, the lacunae rostralis were most prominent in the mid-section of the rostrum. Dorsally, they occurred closer to the tip. The density of lacunae rostralis increased towards the rostrum tip but, because they are smaller in size, the percentage of rostrum coverage decreased. The teeth located within the lacunae rostralis were found to be different in size, location and orientation from the previously identified micro-teeth of billfish. We propose two potential functions of the lacunae rostralis that both relate to the use of the bill in feeding: mechanoreception of prey before tapping it with the bill and more efficient prey handling via the creation of suction, or physical grip.


Asunto(s)
Perciformes , Animales , Peces
15.
New Phytol ; 229(1): 272-283, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32171020

RESUMEN

Structural changes during severe drought stress greatly modify the hydraulic properties of fine roots. Yet, the physiological basis behind the restoration of fine root water uptake capacity during water recovery remains unknown. Using neutron radiography (NR), X-ray micro-computed tomography (micro-CT), fluorescence microscopy, and fine root hydraulic conductivity measurements (Lpr ), we examined how drought-induced changes in anatomy and hydraulic properties of contrasting grapevine rootstocks are coupled with fine root growth dynamics during drought and return of soil moisture. Lacunae formation in drought-stressed fine roots was associated with a significant decrease in fine root Lpr for both rootstocks. However, lacunae formation occurred under milder stress in the drought-resistant rootstock, 110R. Suberin was deposited at an earlier developmental stage in fine roots of 101-14Mgt (i.e. drought susceptible), probably limiting cortical lacunae formation during mild stress. During recovery, we found that only 110R fine roots showed rapid re-establishment of elongation and water uptake capacity and we found that soil water status surrounding root tips differed between rootstocks as imaged with NR. These data suggest that drought resistance in grapevine rootstocks is associated with rapid re-establishment of growth and Lpr near the root tip upon re-watering by limiting competing sites along the root cylinder.


Asunto(s)
Sequías , Vitis , Meristema , Raíces de Plantas , Agua , Microtomografía por Rayos X
16.
Calcif Tissue Int ; 109(5): 586-595, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34003338

RESUMEN

Proteus syndrome is a rare genetic disorder, which is characterized by progressive, segmental, or patchy overgrowth of diverse tissues of all germ layers, including the skeleton. Here, we present a 9-year-old girl with a somatic-activating mutation (c.49G > A; p.Glu17Lys) in AKT1 gene in a mosaic status typical for Proteus syndrome. She presented with hemihypertrophy of the right lower limb and a "moccasin" lesion among others. A transiliac bone biopsy was analyzed for bone histology/histomorphometry as well as bone mineralization density distribution (BMDD) and osteocyte lacunae sections (OLS) characteristics based on quantitative backscattered electron imaging. Bone histomorphometry revealed highly increased mineralizing surface (Z-score + 2.3) and mineral apposition rate (Z-score + 19.3), no osteoclasts (Z-score - 2.1), and an increased amount of primary bone in the external cortex. BMDD abnormalities included a decreased mode calcium concentration in cancellous bone (Z-score - 1.7) and an increased percentage of highly mineralized cortical bone area (Z-score + 2.4) compared to reference. OLS characteristics showed several differences compared to reference data; among them, there were the highly increased OLS-porosity, OLS-area, and OLS-perimeter on the external cortex (Z-scores + 6.8, + 4.4 and 5.4, respectively). Our findings suggest that increased bone formation reduced matrix mineralization in cancellous bone while the enhanced amount of primary bone in the external cortex increased the portion of highly mineralized cortical bone and caused OLS-characteristics abnormalities. Our results indicate further that remodeling of primary bone might be disturbed or delayed in agreement with the decreased number of osteoclasts observed in this child with Proteus syndrome.


Asunto(s)
Síndrome de Proteo , Biopsia , Densidad Ósea , Huesos , Niño , Femenino , Humanos , Fenotipo , Síndrome de Proteo/genética
17.
J Bone Miner Metab ; 39(5): 737-747, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33830351

RESUMEN

BACKGROUND: Bisphosphonate and denosumab are widely used for the treatment of osteoporosis and bone metastasis of cancer to prevent excessive bone resorption. Osteonecrosis of the jaw is a serious adverse effect of bisphosphonate or denosumab referred to as bisphosphonate-related osteonecrosis of the jaw (BRONJ) or denosumab-related osteonecrosis of the jaw (DRONJ), respectively. Since bisphosphonate and denosumab inhibit bone resorption by different mechanism, we evaluated whether these drug types result in different histopathological characteristics related to bone resorption. MATERIALS AND METHODS: We histopathologically investigated 10 cases of BRONJ, DRONJ, and suppurative osteomyelitis. Paraffin sections prepared from decalcified dissected jaw bones were used for histopathological observation, second harmonic generation imaging, and bone histomorphometry. The samples were also observed by a scanning electron microscope. RESULTS: Numerous bone resorption lacunae were observed on the necrotic bone surface in almost all cases of BRONJ; however, such resorption lacunae were limited in DRONJ and suppurative osteomyelitis. Prominent bone resorption lacunae were also confirmed by second harmonic generation imaging and scanning electron microscopy in BRONJ, but not in DRONJ or suppurative osteomyelitis. As determined by bone histomorphometry, the number of bone resorption lacunae and the length of the erosion surface of resorption lacunae were significantly higher in BRONJ group than in the DRONJ and suppurative osteomyelitis groups. These parameters were correlated between the necrotic bones and the vital bones in BRONJ. CONCLUSIONS: Persistent bone resorption lacunae on the necrotic bone surface are unique to BRONJ, providing a basis for distinguishing BRONJ from DRONJ and OM in histopathological diagnosis.


Asunto(s)
Osteonecrosis de los Maxilares Asociada a Difosfonatos , Conservadores de la Densidad Ósea , Neoplasias Óseas , Resorción Ósea , Osteonecrosis , Osteonecrosis de los Maxilares Asociada a Difosfonatos/diagnóstico por imagen , Conservadores de la Densidad Ósea/efectos adversos , Denosumab/efectos adversos , Difosfonatos , Humanos , Osteonecrosis/inducido químicamente , Osteonecrosis/diagnóstico por imagen
18.
Int J Syst Evol Microbiol ; 70(11): 5899-5910, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33016860

RESUMEN

A novel bacterial strain, designated CSW-10T, isolated from a freshwater pond in Taiwan, was characterized using a polyphasic taxonomic approach. Cells were Gram-stain-negative, aerobic, non-motile, rod-shaped and formed yellow-coloured colonies. Optimal growth occurred at 30 °C, pH 7, and in the absence of NaCl. Phylogenetic analyses based on 16S rRNA gene sequences and coding sequences of 92 protein clusters indicated that strain CSW-10T formed a phylogenetic lineage in the genus Sphingomonas. The 16S rRNA gene sequence similarity indicated that strain CSW-10T was most closely related to Sphingomonas fonticola TNR-2T (97.6%). Strain CSW-10T showed 69.8-70.7% average nucleotide identity and 19.0-23.0% digital DNA-DNA hybridization identity with the strains of other related Sphingomonas species. The major fatty acids of strain CSW-10T were summed feature 8 (C18:1 ω7c and/or C18:1 ω6c) and C17:1 ω6c. The polar lipid profile consisted of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidyldimethylethanolamine, phosphatidylcholine, one uncharacterized sphingoglycolipid, five uncharacterized aminophospholipids, one uncharacterized phospholipid and one uncharacterized lipid. The predominant polyamines were homospermidine and spermidine. The major isoprenoid quinone was Q-10. Genomic DNA G+C content of strain CSW-10T was 62.0 mol%. On the basis of phenotypic and genotypic properties and phylogenetic inference, strain CSW-10T should represent a novel species of the genus Sphingomonas, for which the name Sphingomonas lacunae sp. nov. is proposed. The type strain is CSW-10T (=BCRC 81190T =LMG 31340T).


Asunto(s)
Filogenia , Estanques/microbiología , Sphingomonas/clasificación , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Agua Dulce/microbiología , Hibridación de Ácido Nucleico , Fosfolípidos/química , Pigmentación , Poliaminas/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Espermidina/química , Sphingomonas/aislamiento & purificación , Taiwán , Ubiquinona/análogos & derivados , Ubiquinona/química
19.
Int J Syst Evol Microbiol ; 70(4): 2888-2895, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32213255

RESUMEN

A novel bacterial strain, designated KMB7T, isolated from a freshwater pond in Taiwan, was characterized using a polyphasic taxonomic approach. Cells were Gram-stain-negative, motile by means of a single polar flagellum, rod-shaped and formed cream colonies. Optimal growth occurred at 25 °C, pH 7, and in the absence of NaCl. Phylogenetic analyses based on 16S rRNA gene sequences and an up-to-date bacterial core gene set (92 protein clusters) indicated that strain KMB7T is affiliated with species in the genus Aquabacterium. The 16S rRNA gene sequence similarity indicated that strain KMB7T is closely related to species within the genus Aquabacterium (95.2-97.6 % sequence similarity) and is most similar to A. fontiphilum CS-6T (97.6 %), followed by A. parvum B6T (97.5 %). The average nucleotide identity and digital DNA-DNA hybridization identity between strain KMB7T and the closely related strains were 74.6-78.0 % and 19.0-21.2 %, respectively. The major fatty acids of strain KMB7T were summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c), C18 : 1 ω7c and C16 : 0. The polar lipid profile consisted of a mixture of phosphatidylethanolamine, phosphatidylglycerol, phosphatidylserine, diphosphatidylglycerol and four unidentified phospholipids. The sole isoprenoid quinone was ubiquinone-8 (Q-8). Genomic DNA G+C content of strain KMB7T was 65.4 %. On the basis of phenotypic and genotypic properties and phylogenetic inference, strain KMB7T should be classified in a novel species of the genus Aquabacterium, for which the name Aquabacterium lacunae sp. nov. is proposed. The type strain is KMB7T (=BCRC 81156T=LMG 30924T=KCTC 62867T).


Asunto(s)
Burkholderiales/clasificación , Filogenia , Estanques/microbiología , Técnicas de Tipificación Bacteriana , Composición de Base , Burkholderiales/aislamiento & purificación , ADN Bacteriano/genética , Ácidos Grasos/química , Genes Bacterianos , Hibridación de Ácido Nucleico , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Taiwán , Ubiquinona/química
20.
Neurol Sci ; 41(12): 3617-3624, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32458249

RESUMEN

INTRODUCTION: The comorbidity of cerebral small vessel disease (CSVD) may worsen gait impairment of Parkinson's disease (PD). However, the evidence remains scarce and controversial, and the mechanism of their potential interaction remains largely unknown. The present study aimed to investigate the overall impact of quantity and location of CSVD on gait/posture function in PD. METHODS: This cross-sectional study included 315 consecutive eligible patients with PD from Beijing Tiantan Hospital from May 2016 to August 2018. Associations of gait/posture subscores with the burden score of CSVD and four CSVD imaging markers were assessed using multivariate linear regression models. RESULTS: Burden of CSVD was significantly associated with more severe gait/posture impairment in PD in the unadjusted model (ß = 0.521, P = 0.011, 95% CI 0.118-0.923) and in the model adjusted for age, hypertension, ischemic stroke, low-density lipoprotein level, cholesterol level, and cognitive statues (ß = 0.448, P = 0.047, 95% CI 0.006-0.891). The presence of lacunes, but not other CSVD markers, was significantly associated with higher gait/posture subscores after the adjustment (ß = 0.492, P = 0.041, 95% CI 0.021-0.964), and the number of lacunes in the basal ganglia significantly correlated with the gait/posture subscores in patients with PD (P = 0.012, Spearman r = 0.161). CONCLUSIONS: CSVD and lacunes in the basal ganglia may independently contribute to gait/posture dysfunction in PD. Promoting neurovascular health may preserve some gait/posture function of PD.


Asunto(s)
Enfermedades de los Pequeños Vasos Cerebrales , Enfermedad de Parkinson , Enfermedades de los Pequeños Vasos Cerebrales/complicaciones , Enfermedades de los Pequeños Vasos Cerebrales/diagnóstico por imagen , Enfermedades de los Pequeños Vasos Cerebrales/epidemiología , Costo de Enfermedad , Estudios Transversales , Marcha , Humanos , Imagen por Resonancia Magnética , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/epidemiología , Postura
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