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1.
Plant Biol (Stuttg) ; 23(4): 556-563, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33550673

ABSTRACT

Floral structures, such as stamen appendages, play crucial roles in pollinator attraction, pollen release dynamics and, ultimately, the reproductive success of plants. The pollen-rewarding, bee buzz-pollinated flowers of Melastomataceae often bear conspicuous staminal appendages. Surprisingly, their functional role in the pollination process remains largely unclear. We use Huberia bradeana Bochorny & R. Goldenb. (Melastomataceae) with conspicuously elongated, twisted stamen appendages to investigate their functional role in the pollination process. We studied the effect of stamen appendages on pollinator behaviour and reproductive success by comparing manipulated flowers (appendages removed) with unmanipulated flowers. To assess bee pollinator behaviour, we measured three properties of buzzes (vibrations) produced by bees on Huberia flowers: frequency, duration and number of buzzes per flower visit. We measured male and female reproductive success by monitoring pollen release and deposition after single bee visits. Finally, we used artificial vibrations and laser vibrometry to assess how flower vibrational properties change with the removal of stamen appendages. Our results show that the absence of staminal appendages does not modify bee buzzing behaviour. Pollen release was higher in unmanipulated flowers, but stigmatic pollen loads differ only marginally between the two treatments. We also detected lower vibration amplitudes in intact flowers as compared to manipulated flowers in artificial vibration experiments. The presence of connective appendages are crucial in transmitting vibrations and assuring optimal pollen release. Therefore, we propose that the high diversity of colours, shapes and sizes of connective appendages in buzz-pollinated flowers may have evolved by selection through male fitness.


Subject(s)
Melastomataceae , Pollination , Animals , Bees , Flowers , Pollen , Reproduction
2.
Endocrine ; 72(3): 711-720, 2021 06.
Article in English | MEDLINE | ID: mdl-33030666

ABSTRACT

PURPOSE: In presence of indeterminate lesions by fine needle aspiration (FNA), thyroid cancer cannot always be easily diagnosed by conventional cytology. As a consequence, unnecessary removal of thyroid gland is performed in patients without cancer based on the lack of optimized diagnostic criteria. Aim of this study is identifying a molecular profile based on long noncoding RNAs (lncRNAs) expression capable to discriminate between benign and malignant nodules. METHODS: Patients were subjected to surgery (n = 19) for cytologic suspicious thyroid nodules or to FNA biopsy (n = 135) for thyroid nodules suspicious at ultrasound. Three thyroid-specific genes (TG, TPO, and NIS), six cancer-associated lncRNAs (MALAT1, NEAT1, HOTAIR, H19, PVT1, MEG3), and two housekeeping genes (GAPDH and P0) were analyzed using Droplet Digital PCR (ddPCR). RESULTS: Based on higher co-expression in malignant (n = 11) but not in benign (n = 8) nodules after surgery, MALAT1, PVT1 and HOTAIR were selected as putative cancer biomarkers to analyze 135 FNA samples. Cytological and histopathological data from a subset of FNA patients (n = 34) were used to define a predictive algorithm based on a Naïve Bayes classifier using co-expression of MALAT1, PVT1, HOTAIR, and cytological class. This classifier exhibited a significant separation capability between malignant and benign nodules (P < 0.0001) as well as both rule in and rule out test potential with an accuracy of 94.12% and a negative predictive value (NPV) of 100% and a positive predictive value (PPV) of 91.67%. CONCLUSIONS: ddPCR analysis of selected lncRNAs in FNA biopsies appears a suitable molecular tool with the potential of improving diagnostic accuracy.


Subject(s)
RNA, Long Noncoding , Thyroid Neoplasms , Thyroid Nodule , Bayes Theorem , Biopsy, Fine-Needle , Early Detection of Cancer , Humans , RNA, Long Noncoding/genetics , Sensitivity and Specificity , Thyroid Neoplasms/diagnosis , Thyroid Neoplasms/genetics , Thyroid Nodule/diagnosis , Thyroid Nodule/genetics
3.
Phys Rev Lett ; 123(4): 044801, 2019 Jul 26.
Article in English | MEDLINE | ID: mdl-31491266

ABSTRACT

The interaction rate of a charged particle beam with the atomic nuclei of a target varies significantly if the target has a crystalline structure. In particular, under specific orientations of the target with respect to the incident beam, the probability of inelastic interaction with nuclei can be enhanced with respect to the unaligned case. This effect, which can be named antichanneling, can be advantageously used in the cases where the interaction between beam and target has to be maximized. Here we propose to use antichanneling to increase the radioisotope production yield via cyclotron. A dedicated set of experimental measurements was carried out at the INFN Legnaro Laboratories with the AN2000 and CN accelerators to prove the existence of the antichanneling effect. The variation of the interaction yield at hundreds of keV to MeV energies was observed by means of sapphire and indium phosphide crystals, achieving an enhancement of the interaction rate up to 73% and 25%, respectively. Such a result may pave the way to the development of a novel type of nozzle for the existing cyclotrons, which can exploit crystalline materials as targets for radioisotope production, especially to enhance the production rate for expensive prime materials with minor upgrades of the current instrumentation.

4.
Neotrop Entomol ; 48(3): 515-521, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30637578

ABSTRACT

Nasutitermes corniger (Motschulsky, 1855) (Termitidae: Nasutitermitinae) is an important pest in urban environments and bioinsecticides can be an alternative to its control. Here, we determined the toxicity and repellence of the essential oil (EO) prepared from stems of Aristolochia trilobata L. (Aristolochiaceae) and its major constituents on N. corniger. We also investigated behavioral changes of individuals exposed to limonene. The lethal dose required to kill 50% of N. corniger population (LD50) of EO of A. trilobata was 2.44 µg mg-1. Limonene was the most toxic compound to N. corniger followed by linalool (LD50 = 1.02 and 1.29 µg mg-1, respectively). In addition, all treatments presented median lethal time (LT50) less than 11 h. A. trilobata EO and its constituents showed irritability activity, but only limonene repelled soldiers more than workers. The negative behaviors of N. corniger groups were higher in individuals treated with limonene. A. trilobata EO and its constituents, especially the limonene, are promising for the control of N. corniger due the high toxicity, repellence, and possible disturbance in the colonies.


Subject(s)
Aristolochia/chemistry , Insecticides , Isoptera , Oils, Volatile , Acyclic Monoterpenes , Animals , Insect Repellents , Limonene , Monoterpenes , Plant Oils , Toxicity Tests, Acute
5.
Neotrop Entomol ; 47(6): 769-779, 2018 Dec.
Article in English | MEDLINE | ID: mdl-29995283

ABSTRACT

Leaf-cutting ants belonging to the genus Atta (Formicidae: Myrmicinae) are important pests in agricultural and forest environments. In the present study, we evaluated the formicidal activity of the essential oil of Pogostemon cablin and its nanoformulation on the leaf-cutting ants: Atta opaciceps (Borgmeier, 1939), Atta sexdens (Linnaeus, 1758), and Atta sexdens rubropilosa Forel, 1908. The nanoformulation was developed by magnetic stirring using polyoxyethylene (36%), pure ethanol (36%), essential oil of P. cablin (18%), and water (10%). Bioassays of acute toxicity by fumigation and behavioral bioassays in treated arenas, with and without choice, were performed. The essential oil of P. cablin and its nanoformulation demonstrated efficient insecticidal activity and irritability to ant species. The concentration required to kill 50% of workers varied from 1.06 to 2.10 µL L-1, with a mean time to death of less than or equal to 42 h. The essential oil of P. cablin and its nanoformulation reduced the displacement and velocity speed of the workers of A. opaciceps and A. sexdens rubropilosa in totally treated arenas. In the bioassays with choices, the three species of ants walked less and at a greater speed on the treated side of arena. This work demonstrates the potential of the essential oil of P. cablin and its nanoformulation to the generation of new formicidal products.


Subject(s)
Ants , Insecticides , Oils, Volatile , Pogostemon/chemistry , Animals , Behavior, Animal , Toxicity Tests, Acute
6.
J Econ Entomol ; 108(2): 611-20, 2015 Apr.
Article in English | MEDLINE | ID: mdl-26470172

ABSTRACT

The impact of the fungicides mancozeb, myclobutanil, and meptyldinocap on populations of Typhlodromus pyri Scheuten was evaluated under field conditions, when applied following the good agricultural practices recommended for their use. Two complementary statistical models were used to analyze the population reduction compared to the control: a linear mixed model to estimate the mean effect of the fungicide, and a generalized linear mixed model (proportional odds mixed model) to estimate the cumulative probability for those effects being equal or less than a specific IOBC class (International Organization for Biological and Integrated Control of Noxious Animal and Plants). Findings from 27 field experiments in a range of different vine-growing regions in Europe indicated that the use of mancozeb, myclobutanil, and meptyldinocap caused minimal impact on naturally occurring populations of T. pyri. Both statistical models confirmed that although adverse effects on T. pyri can occur under certain conditions after several applications of any of the three fungicides studied, the probability of the effects occurring is low and they will not persist. These methods demonstrated how data from a series of trials could be used to evaluate the variability of the effects caused by the chemical rather than relying on the worst-case findings from a single trial.


Subject(s)
Fungicides, Industrial , Mites , Animals , Dinitrobenzenes , Europe , Maneb , Models, Statistical , Nitriles , Triazoles , Vitis , Zineb
7.
Radiat Prot Dosimetry ; 157(4): 491-8, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23843425

ABSTRACT

Action spectrum (AS) describes the relative effectiveness of ultraviolet (UV) radiation in producing biological effects and allows spectral UV irradiance to be weighted in order to compute biologically effective UV radiation (UVBE). The aim of this research was to study the seasonal and latitudinal distribution over Europe of daily UVBE doses responsible for various biological effects on humans and plants. Clear sky UV radiation spectra were computed at 30-min time intervals for the first day of each month of the year for Rome, Potsdam and Trondheim using a radiative transfer model fed with climatological data. Spectral data were weighted using AS for erythema, vitamin D synthesis, cataract and photokeratitis for humans, while the generalised plant damage and the plant damage AS were used for plants. The daily UVBE doses for the above-mentioned biological processes were computed and are analysed in this study. The patterns of variation due to season (for each location) and latitude (for each date) resulted as being specific for each adopted AS. The biological implications of these results are briefly discussed highlighting the importance of a specific UVBE climatology for each biological process.


Subject(s)
Environmental Monitoring/methods , Eye/radiation effects , Ultraviolet Rays , Atmosphere , Cataract/epidemiology , Climate , Environmental Exposure , Erythema/epidemiology , Germany , Humans , Italy , Keratitis/epidemiology , Norway , Plants/radiation effects , Quality Control , Seasons , Vitamin D/biosynthesis , Weather
8.
Phys Rev Lett ; 108(1): 014801, 2012 Jan 06.
Article in English | MEDLINE | ID: mdl-22304263

ABSTRACT

The interaction of a 2 MeV proton beam with an ultrathin unbent Si crystal was studied through simulation and experiment. Crystal thickness along the beam was set at 92 nm, i.e., at half the oscillation wavelength of the protons in the crystal under planar channeling condition. As the nominal beam direction is inclined by less than the critical angle for planar channeling with respect to the crystal planes, under-barrier particles undergo half an oscillation and exit the crystal with the reversal of the transverse momenta; i.e., the protons are "mirrored" by the crystal planes. Over-barrier particles suffer deflection, too, to a direction opposite that of mirroring with a dynamics similar to that of volume reflection in a bent crystal. On the strength of such coherent interactions, charged particle beams can be efficiently steered through an ultrathin unbent crystal by the same physical processes as for thicker bent crystals.

9.
Archivos de zootecnia ; 61: 67-78, 2012.
Article in Portuguese | LILACS, MOSAICO - Integrative health | ID: biblio-948638

ABSTRACT

O carrapato bovino Riphicephalus microplus (Acari: Ixodidae) constitui um dos grandes problemas enfrentado pelos pecuaristas de várias partes do mundo. No Brasil este ectoparasita causa grandes prejuízos à bovinocultura devido ao processo de hematofagia e pela transmissão de agentes patogênicos nos animais hospedeiros. Diante dessa situação os produtores normalmente aplicam carrapaticidas organossintéticos de forma indiscriminada. Este método normalmente resulta em: intoxicação dos animais e dos aplicadores, resíduos de carrapaticidas nos produtos de origem animal, resistência dos carrapatos aos carrapaticidas químicos e poluição ambiental. Uma alternativa para diminuir esses problemas é uso de biocarrapaticidas de origem botânica. Os pesticidas botânicos são produtos naturais derivados do metabolismo secundário das plantas. Esse metabolismo produz uma grande diversidade de compostos com ação carrapaticida que podem ser explorados através do uso de óleos essenciais ou como modelo para síntese de pesticidas sintéticos. A necessidade de métodos mais seguros, menos agressivos ao homem e ao meio ambiente, tem estimulado a busca de novos carrapaticidas a partir de produtos vegetais. Assim, acredita-se que o uso de óleos essenciais de plantas medicinais e aromáticas de uma forma isolada ou associada pode reduzir: a velocidade do desenvolvimento da resistência dos carrapatos aos carrapaticidas, os resíduos nos produtos de origem animal e a toxicidade para os animais, aplicadores e meio ambiente.


Subject(s)
Plants, Medicinal , Oils, Volatile , Brazil , Rhipicephalus
10.
Bull Entomol Res ; 97(4): 421-32, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17645824

ABSTRACT

Seasonal population fluctuation of the coffee leafminer, Leucoptera coffeella (Guérin-Méneville & Perrottet) (Lepidoptera: Lyonetiidae), led to an investigation of its natural mortality factors during the rainy season when the population level is low and during the dry season when population peaks occur. Life-table data were collected from insecticide-free plots within a 3 ha coffee plantation on the upper, medium and lower canopy. Leafminer mortality was similar among the canopy parts but varied in the two seasons studied. During the rainy season, the generational mortality averaged 94.3%, with 50.2, 33.7 and 10.4% occurring during egg, larval and pupal stages, respectively. During the dry season, total mortality was 89%, with 13.2, 61.0 and 14.8% occurring during egg, larval and pupal stages, respectively. Marginal mortality rates during the rainy season were highest for physiological disturbances, rainfall and egg inviability; but, in the dry season, they were highest for predaceous wasps, physiological disturbances and parasitoids. Egg and larval stages accounted for most of the mortality variation in the rainy season, while the combination of larval and pupal mortality better described the generational mortality in the dry season. Variation in mortality during the rainy season was primarily associated with egg inviability, rainfall and parasitoids. In contrast, predatory wasps and physiological disturbances were the main factors associated with mortality variation during the dry season. These results suggest that weather conditions, natural enemies and plant quality attributes are the main determinants of the population dynamics of L. coffeella.


Subject(s)
Life Cycle Stages , Moths/growth & development , Seasons , Animals , Coffea/parasitology , Life Tables , Population Dynamics
11.
Rev Hosp Clin Fac Med Sao Paulo ; 44(2): 58-62, 1989.
Article in Portuguese | MEDLINE | ID: mdl-2616988

ABSTRACT

The correct determination of the 24 hours proteinuria (PU24) in the non-hospitalized patients is frequently subject to collection errors. To overcome this problem it has been proposed the use of the proteinuria ratio (PR), obtained by dividing the concentrations of protein/creatinine in random urine samples. In the present investigation PR and PU24 were correlated in 42 patients (22 male and 20 female), aged between 14 and 63 years. Each patient was submitted to a 2 hours creatinine clearance (Ccr), to determination of PU24 and to evaluation of PR in the urine samples. The measures of PU24 were correlated with the values of PR. On linear regression analysis the equation y = 0,517 + 0,759x was obtained, with r = 0,914, suggesting good correlation between PU24 and PR. Values of r greater than 0,9 were always obtained, independently of the values of Ccr and PU24. The results indicate that PR in random urine samples may be practical and reliable in the follow-up of nephrological patients.


Subject(s)
Creatinine/urine , Proteinuria/urine , Adolescent , Adult , Female , Humans , Male , Middle Aged , Regression Analysis , Specimen Handling
12.
Diabete Metab ; 11(1): 3-8, 1985 Feb.
Article in English | MEDLINE | ID: mdl-3884404

ABSTRACT

The effect of prolonged restoration of near-normoglycemia on the progression of diabetic nephropathy was evaluated in a controlled study in which 10 insulin-dependent (type 1) diabetic patients with clinical proteinuria were randomized to continue with conventional insulin treatment (CIT) or to undertake more intensive diabetic therapy using continuous subcutaneous insulin infusion (CSII). The patients, mean age 33 +/- 8 yr, mean duration of diabetes 15 +/- 4 yr, were studied before and during 12 months of either CIT or CSII therapy. Glycemic control was assessed by means of mean blood glucose (MBG) +/- Standard deviation (SD), urinary glucose excretion and glycosylated hemoglobin, while renal function was assessed by albumin, IgG and beta-2-microglobulin urinary excretion rates, serum creatinine and creatinine clearance. Blood glucose level, urinary glucose excretion and glycosylated hemoglobin fell significantly in the CSII group, while no differences were found in the CIT group after the 12 months observation period. Both groups showed a deterioration in all indices of renal function, as illustrated by an increase of protein excretion rates and of serum creatinine, and by a decline in creatinine clearance. Comparison of the rate of increase of urinary albumin and IgG excretion and of serum creatinine and of the rate of fall in creatinine clearance between CIT and CSII groups demonstrated that the rate of progression of diabetic nephropathy may be slowed by correction of hyperglycemia. Our study, with due reservations because of the small number of examined patients and differences in kidney function at the beginning of the trial shows that intensive diabetic care may play a role in the proteinuric stage of diabetes in slowing further destruction of residual glomerular structure and in delaying end stage renal failure.


Subject(s)
Blood Glucose , Diabetes Mellitus, Type 1/blood , Diabetic Nephropathies/blood , Adult , Albuminuria , Creatinine/blood , Creatinine/urine , Diabetes Mellitus, Type 1/drug therapy , Diabetes Mellitus, Type 1/urine , Diabetic Nephropathies/drug therapy , Diabetic Nephropathies/urine , Glycated Hemoglobin/urine , Glycosuria , Humans , Immunoglobulin G/urine , Insulin/administration & dosage , Insulin/therapeutic use , Insulin Infusion Systems , Male , beta 2-Microglobulin/urine
14.
Diabetes Care ; 5(6): 624-9, 1982.
Article in English | MEDLINE | ID: mdl-6927732

ABSTRACT

To evaluate the effect of improved metabolic control on kidney function, urinary excretion rate of beta-2-microglobulin, lysozyme, and gamma-glutamyltransferase were evaluated in nine poorly controlled, newly diagnosed diabetic patients before and during treatment. In six poorly controlled insulin-dependent nephropathic diabetic patients, besides the parameters cited above, urinary albumin excretion rate and IgG/transferrin clearance ratio were further investigated to estimate the permeability and the selectivity of glomerular barrier during conventional treatment and after improvement of the metabolic control by a glucose-controlled insulin infusion system (GCIIS). The improved glycemic control resulted in a significant reduction of urinary beta-2-microglobulin and lysozyme excretion in all diabetic patients. Significant decreases of urinary albumin excretion and of IgG/transferrin clearance ratio (indicating a more selective proteinuria) during strict metabolic control were also observed in nephropathic diabetic patients. The reduction of urinary beta-2-microglobulin and lysozyme excretion indicates that a tubular reabsorptive dysfunction, reversible with the amelioration of glycemic control, can be observed in poorly controlled, newly diagnosed and in insulin-dependent nephropathic diabetic patients during conventional treatment. In the latter patients, the permeability and the selectivity properties of glomerular barrier also improved during GCIIS.


Subject(s)
Diabetes Mellitus, Type 1/drug therapy , Diabetic Nephropathies/drug therapy , Insulin Infusion Systems , Kidney Function Tests , Adult , Female , Humans , Male
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