ABSTRACT
The water relations and hydraulic architecture of growing grass tillers (Festuca arundinacea Schreb.) are reported. Evaporative flux density, E (mmol s−1 m−2), of individual leaf blades was ...measured gravimetrically by covering or excision of entire leaf blades. Values of E were similar for mature and elongating leaf blades, averaging 2·4 mmol s−1 m−2. Measured axial hydraulic conductivity, Kh (mmol s−1 mm MPa−1), of excised leaf segments was three times lower than theoretical hydraulic conductivity (Kt) calculated using the Poiseuille equation and measurements of vessel number and diameter. Kt was corrected (Kt*) to account for the discrepancy between Kh and Kt and for immature xylem in the basal expanding region of elongating leaves. From base to tip of mature leaves the pattern of Kt* was bell‐shaped with a maximum near the sheath–blade joint (≈ 19 mmol s−1 mm MPa−1). In elongating leaves, immature xylem in the basal growing region led to a much lower Kt*. As the first metaxylem matured, Kt* increased by 10‐fold. The hydraulic conductances of the whole root system, (mmol s−1 MPa−1) and leaf blades, (mmol s−1 MPa−1) were measured by a vacuum induced water flow technique. and were linearly related to the leaf area downstream. Approximately 65% of the resistance to water flow within the plant resided in the leaf blade. An electric‐analogue computer model was used to calculate the leaf blade area‐specific radial hydraulic conductivity, (mmol s−1 m−2 MPa−1), using , Kt* and water flux values. values decreased with leaf age, from 21·2 mmol s−1 m−2 MPa−1 in rapidly elongating leaf to 7·2 mmol s−1 m−2 MPa−1 in mature leaf. Comparison of and values showed that ≈ 90% of the resistance to water flow within the blades resided in the liquid extra‐vascular path. The same algorithm was then used to compute the xylem and extravascular water potential drop along the liquid water path in the plant under steady state conditions. Predicted and measured water potentials matched well. The hydraulic design of the mature leaf resulted in low and quite constant xylem water potential gradient (≈ 0·3 MPa m−1) throughout the plant. Much of the water potential drop within mature leaves occurred within a tenth of millimetre in the blade, between the xylem vessels and the site of water evaporation within the mesophyll. In elongating leaves, the low Kt* in the basal growth zone dramatically increased the local xylem water potential gradient (≈ 2·0 MPa m−1) there. In the leaf elongation zone the growth‐induced water potential difference was ≈ 0·2 MPa.
Synopsis
The aim of this study was to evaluate the possible penetration through human skin of organic and inorganic filters contained in sunscreen emulsions packaged in aerosol cans, using an in ...vitro method. Experiments were carried out on two different types of emulsion: W/Si and W/O. This study was conducted using static diffusion cells (Franz cells). The determination of organic UV filters Methylene Bis Benzotriazolyl Tetramethylbutylphenol (MBBT); Bis‐Ethylhexyloxyphenol Methoxyphenyl Triazine (BEMT); Diethylamino Hydroxybenzoyl Hexyl Benzoate (DHHB); Ethylhexyl Methoxycinnamate (EMC); and 2‐Ethylhexyl Dimethyl PABA (ED‐PABA) was performed by High Performance Liquid Chromatography (HPLC). Therefore, it was important to develop a single analytical method for the quantification of the five organic filters with the aim of facilitating the experiment. The determination of inorganic filters titanium dioxide (TiO2) and zinc oxide (ZnO) was performed using an emission spectrometric analysis method (ICP‐OES). The HPLC and ICP‐OES methods were validated. After a penetration test of 24 h duration, the results showed very low penetration only for two of the organic filters (maximum penetration of 1.21 μg cm−2 h−1 for EMC and 0.14 μg cm−2 h−1 for MBBT) and no penetration for the inorganic filters. Moreover, more than 50% of each sunscreen agent stayed on the surface on the skin. These results are consistent with those in the literature that presents similar experiments. This study showed that the sprayable sunscreen products developed, which contained high concentrations of UV filters, presented a low level of skin penetration.
Résumé
Le but de cette étude était d’évaluer le potentiel de pénétration cutanée de filtres organiques et inorganiques contenus dans des émulsions solaires conditionnées sous forme d’aérosol en utilisant une méthode in vitro. Pour cela, des méthodes analytiques ont dûêtre mises au point. Ces expériences ont été réalisées sur deux types d’émulsion (E/H et E/Si). Cette étude a été réalisée en utilisant des cellules de diffusion statiques (Cellules de Franz). La détermination des filtres UV organiques (Methylene Bis Benzotriazolyl Tetramethylbutylphenol (MBBT); Bis‐Ethylhexyloxyphenol Methoxyphenyl Triazine (BEMT); Diethylamino Hydroxybenzoyl Hexyl Benzoate (DHHB); Ethylhexyl Methoxycinnamate (EMC); 2‐Ethylhexyl Dimethyl PABA (ED‐PABA)) a été effectuée à 1’aide de la Chromatographie Liquide Haute Performance (CLHP). II était done important de developper une méthode unique pour la quantification des cinq filtres organiques en présence dans le but de faciliter 1’étude. La determination des filtres inorganiques (dioxyde de titane (TiO2) et oxyde de zinc (ZnO)) a été accomplie en utilisant une méthode d’émission spectrométrique (ICP‐OES). Ces deux méthodes analytiques ont été validées. Après une durée de test de 24 h, les résultats ont montré une très faible pénétration pour deux des filtres organiques (Maximum 1.21 μg/cm2/h pour 1’EMC et 0.14 μg/cm2/h pour le MBBT) et pas de pénétration pour les filtres inorganiques. De plus, plus de 50% des filtres UV restent à la surface de la peau. Les résultats obtenus corroborent ceux présentés dans la littérature. Des produits solaires sprayable contenant de fortes concentrations en filtres UV et possédant un faible taux de passage cutané ont été développés.
This post hoc analysis of international phase III isavuconazole trials identified 50 patients (90% immunocompromised or diabetic) with invasive fungal sinusitis (88% mucormycetes, Aspergillus) who ...received isavuconazole as primary (n = 33) or salvage (n = 17) therapy for a median of 82 days (range, 2-882). Overall survival was 82% at day 42 and 70% at day 84.
To characterize acute bacterial meningitis in adults, we reviewed the charts of all persons 16 years of age or older in whom acute bacterial meningitis was diagnosed at Massachusetts General Hospital ...from 1962 through 1988. We included patients who were admitted after initial treatment at other hospitals.
During the 27-year period, 445 adults were treated for 493 episodes of acute bacterial meningitis, of which 197 (40 percent) were nosocomial. Gram-negative bacilli (other than Haemophilus influenzae) caused 33 percent of the nosocomial episodes but only 3 percent of the community-acquired episodes. In the 296 episodes of community-acquired meningitis, the most common pathogens were Streptococcus pneumoniae (37 percent), Neisseria meningitidis (13 percent), and Listeria monocytogenes (10 percent); these organisms accounted for only 8 percent of the nosocomial episodes. Only 19 of the 493 episodes of meningitis (4 percent) were due to H. influenzae. Nine percent of all patients had recurrent meningitis; many had a cerebrospinal fluid leak. Seizures occurred in 23 percent of patients with community-acquired meningitis, and 28 percent had focal central nervous system findings. Risk factors for death among those with single episodes of community-acquired meningitis included older age (> or = 60 years), obtunded mental state on admission, and seizures within the first 24 hours. Among those with single episodes, the in-hospital mortality rate was 25 percent for community-acquired and 35 percent for nosocomial meningitis. The overall case fatality rate was 25 percent and did not vary significantly over the 27 years.
In our large urban hospital, a major proportion of cases of acute bacterial meningitis in adults were nosocomial. Recurrent episodes of meningitis were frequent. The overall mortality rate remained high.
To assess the use of molecular genotyping to accurately diagnose and treat human chorionic gonadotropin (hCG)-producing tumors and to evaluate the discriminating capacity of molecular testing on ...prognosis and overall survival.
We conducted a retrospective descriptive study of patients registered with the French Reference Center for Trophoblastic Disease between 1999 and 2021. We included all patients with hCG-producing tumors for whom results of molecular genotyping were available.
Fifty-five patients with molecular genotyping were included: 81.2 % (n = 45) had tumors of gestational origin, 12.7 % (n = 7) of non-gestational origin and 5.5 % (n = 3) of undetermined origin. The results of molecular genotyping influenced the treatment decisions for 17 % of patients in this cohort. Overall survival was 93.3 % for patients with gestational tumors (after a median follow-up of 74 months) compared to 71.4 % for patients with non-gestational tumors (after a median follow-up of 23 months).
In atypical presentations of hCG-producing tumors, molecular genotyping is a valuable tool to guide diagnosis and tailor treatment recommendations.
The main difficulty of ovarian tissue autograft (OTA) is to preserve as many follicles as possible because the ovarian tissue undergoes warm ischemia during grafting until revascularisation, ...resulting in significant follicular loss. We describe a two-stage grafting technique to stimulate new vascularisation in order to enhance the revascularization process to reduce the ischemic injuries. Furthermore we performed ovarian patchwork in the laboratory and then grafting with robotic laparoscopy to facilitate surgery and increase precision. This technique is used in the DATOR study with promising results, such as a 40% delivery rate.
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