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1.
Front Cell Neurosci ; 18: 1398862, 2024.
Article in English | MEDLINE | ID: mdl-38988663

ABSTRACT

The histochemical Falck-Hillarp method for the localization of dopamine (DA), noradrenaline (NA) and serotonin in the central nervous system (CNS) of rodents was introduced in the 1960s. It supported the existence of chemical neurotransmission in the CNS. The monoamine neurons in the lower brain stem formed monosynaptic ascending systems to the telencephalon and diencephalon and monoamine descending systems to the entire spinal cord. The monoamines were early on suggested to operate via synaptic chemical transmission in the CNS. This chemical transmission reduced the impact of electrical transmission. In 1969 and the 1970s indications were obtained that important modes of chemical monoamine communication in the CNS also took place through the extra-synaptic fluid, the extracellular fluid, and long-distance communication in the cerebrospinal fluid involving diffusion and flow of transmitters like DA, NA and serotonin. In 1986, this type of transmission was named volume transmission (VT) by Agnati and Fuxe and their colleagues, also characterized by transmitter varicosity and receptor mismatches. The short and long-distance VT pathways were characterized by volume fraction, tortuosity and clearance. Electrical transmission also exists in the mammalian CNS, but chemical transmission is in dominance. One electrical mode is represented by electrical synapses formed by gap junctions which represent low resistant passages between nerve cells. It allows for a more rapid passage of action potentials between nerve cells compared to chemical transmission. The second mode is based on the ability of synaptic currents to generate electrical fields to modulate chemical transmission. One aim is to understand how chemical transmission can be integrated with electrical transmission and how putative (aquaporin water channel, dopamine D2R and adenosine A2AR) complexes in astrocytes can significancy participate in the clearance of waste products from the glymphatic system. VT may also help accomplish the operation of the acupuncture meridians essential for Chinese medicine in view of the indicated existence of extracellular VT pathways.

2.
Talanta ; 276: 126293, 2024 Aug 15.
Article in English | MEDLINE | ID: mdl-38788383

ABSTRACT

In this work we present the development of an electrochemiluminescence aptasensor based on electrografting molybdenum disulphide nanosheets functionalized with diazonium salt (MoS2-N2+) upon screen-printed electrodes of graphene (SPEs GPH) for viral proteins detection. In brief, this aptasensor consists of SPEs GPH electrografted with MoS2-N2+ and modified with a thiolated aptamer, which can specifically recognize the target protein analyte. In this case, we have used SARS-CoV-2 spike protein as model protein. Electrochemiluminescence detection was performed by using the [Ru(bpy)3]2+/TPRA (tripropylamine) system, which allows the specific detection of the SARS-CoV-2 spike protein easily and rapidly with a detection limit of 9.74 fg/mL and a linear range from 32.5 fg/mL to 50.0 pg/mL. Moreover, the applicability of the aptasensor has been confirmed by the detection of the protein directly in human saliva samples. Comparing our device with a traditional saliva antigen test, our aptasensor can detect the spike protein even when the saliva antigen test gives a negative result.


Subject(s)
Aptamers, Nucleotide , Biosensing Techniques , Disulfides , Electrochemical Techniques , Graphite , Luminescent Measurements , Molybdenum , SARS-CoV-2 , Spike Glycoprotein, Coronavirus , Graphite/chemistry , Disulfides/chemistry , Molybdenum/chemistry , Aptamers, Nucleotide/chemistry , Electrochemical Techniques/methods , Biosensing Techniques/methods , SARS-CoV-2/isolation & purification , SARS-CoV-2/immunology , Humans , Luminescent Measurements/methods , Spike Glycoprotein, Coronavirus/analysis , Limit of Detection , COVID-19/diagnosis , COVID-19/virology , Electrodes , Saliva/chemistry , Saliva/virology
3.
Chem Sci ; 15(10): 3428-3445, 2024 Mar 06.
Article in English | MEDLINE | ID: mdl-38455011

ABSTRACT

The chemical modification of 2D materials has proven a powerful tool to fine tune their properties. With this motivation, the development of new reactions has moved extremely fast. The need for speed, together with the intrinsic heterogeneity of the samples, has sometimes led to permissiveness in the purification and characterization protocols. In this review, we present the main tools available for the chemical characterization of functionalized 2D materials, and the information that can be derived from each of them. We then describe examples of chemical modification of 2D materials other than graphene, focusing on the chemical description of the products. We have intentionally selected examples where an above-average characterization effort has been carried out, yet we find some cases where further information would have been welcome. Our aim is to bring together the toolbox of techniques and practical examples on how to use them, to serve as guidelines for the full characterization of covalently modified 2D materials.

4.
Am J Physiol Renal Physiol ; 326(5): F727-F736, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38511219

ABSTRACT

Although obesity is recognized as a risk factor for cardiorenal and metabolic diseases, the impact of parental obesity on the susceptibility of their offspring to renal injury at adulthood is unknown. We examined the impact of parental obesity on offspring kidney function, morphology, and markers of kidney damage after acute kidney injury (AKI). Offspring from normal (N) diet-fed C57BL/6J parents were fed either N (NN) or a high-fat (H) diet (NH) from weaning until adulthood. Offspring from obese H diet-fed parents were fed N (HN) or H diet (HH) after weaning. All offspring groups were submitted to bilateral AKI by clamping the left and right renal pedicles for 30 min. Compared with male NH and NN offspring from lean parents, male HH and HN offspring from obese parents exhibited higher kidney injury markers such as urinary, renal osteopontin, plasma creatinine, urinary albumin excretion, and neutrophil gelatinase-associated lipocalin (NGAL) levels, and worse histological injury score at 22 wk of age. Only albumin excretion and NGAL were elevated in female HH offspring from obese parents compared with lean and obese offspring from lean parents. We also found an increased mortality rate and worse kidney injury scores after AKI in male offspring from obese parents, regardless of the diet consumed after weaning. Female offspring were protected from major kidney injury after AKI. These results indicate that parental obesity leads to increased kidney injury in their offspring after ischemia-reperfusion in a sex-dependent manner, even when their offspring remain lean.NEW & NOTEWORTHY Offspring from obese parents are more susceptible to kidney injury and worse outcomes following an acute ischemia-reperfusion insult. Male, but not female, offspring from obese parents exhibit increased blood pressure early in life. Female offspring are partially protected against major kidney injury induced by ischemia-reperfusion.


Subject(s)
Acute Kidney Injury , Kidney , Mice, Inbred C57BL , Reperfusion Injury , Animals , Male , Female , Reperfusion Injury/pathology , Reperfusion Injury/metabolism , Acute Kidney Injury/etiology , Acute Kidney Injury/metabolism , Acute Kidney Injury/physiopathology , Acute Kidney Injury/pathology , Kidney/physiopathology , Kidney/pathology , Kidney/metabolism , Sex Factors , Obesity/complications , Obesity/physiopathology , Diet, High-Fat , Pregnancy , Lipocalin-2/metabolism , Obesity, Maternal/metabolism , Obesity, Maternal/complications , Obesity, Maternal/physiopathology , Prenatal Exposure Delayed Effects , Mice , Risk Factors , Disease Models, Animal , Biomarkers/blood
5.
Chemistry ; 30(28): e202303809, 2024 May 17.
Article in English | MEDLINE | ID: mdl-38465520

ABSTRACT

Patterning of graphene (functionalizing some areas while leaving others intact) is challenging, as all the C atoms in the basal plane are identical, but it is also desirable for a variety of applications, like opening a bandgap in the electronic structure of graphene. Several methods have been reported to pattern graphene, but most of them are very technologically intensive. Recently, we reported the use of microemulsions as templates to pattern graphene at the µm scale. This method is very simple and in principle tunable, as emulsions of different droplet size and composition can be prepared easily. Here, we explore in detail the scope of this methodology by applying it to all the combinations of four different emulsions and three different organic reagents, and characterizing the resulting substrates exhaustively through Raman, SEM and AFM. We find that the method is general, works better when the reactive species are outside the micelles, and requires reactive species that involve short reaction times.

6.
Front Microbiol ; 15: 1356966, 2024.
Article in English | MEDLINE | ID: mdl-38389534

ABSTRACT

Forages and concentrates have consistently distinct patterns of fermentation in the rumen, with forages producing more methane (CH4) per unit of digested organic matter (OM) and higher acetate to propionate ratio than concentrates. A mechanism based on the Monod function of microbial growth has been proposed to explain the distinct fermentation pattern of forages and concentrates, where greater dilution rates and lower pH associated with concentrate feeding increase dihydrogen (H2) concentration through increasing methanogens growth rate and decreasing methanogens theoretically maximal growth rate, respectively. Increased H2 concentration would in turn inhibit H2 production, decreasing methanogenesis, inhibit H2-producing pathways such as acetate production via pyruvate oxidative decarboxylation, and stimulate H2-incorporating pathways such as propionate production. We examined the hypothesis that equalizing dilution rates in serial rumen cultures would result in a similar fermentation profile of a high forage and a high concentrate substrate. Under a 2 × 3 factorial arrangement, a high forage and a high concentrate substrate were incubated at dilution rates of 0.14, 0.28, or 0.56 h-1 in eight transfers of serial rumen cultures. Each treatment was replicated thrice, and the experiment repeated in two different months. The high concentrate substrate accumulated considerably more H2 and formate and produced less CH4 than the high forage substrate. Methanogens were nearly washed-out with high concentrate and increased their initial numbers with high forage. The effect of dilution rate was minor in comparison to the effect of the type of substrate. Accumulation of H2 and formate with high concentrate inhibited acetate and probably H2 and formate production, and stimulated butyrate, rather than propionate, as an electron sink alternative to CH4. All three dilution rates are considered high and selected for rapidly growing bacteria. The archaeal community composition varied widely and inconsistently. Lactate accumulated with both substrates, likely favored by microbial growth kinetics rather than by H2 accumulation thermodynamically stimulating electron disposal from NADH into pyruvate reduction. In this study, the type of substrate had a major effect on rumen fermentation largely independent of dilution rate and pH.

7.
Nanoscale ; 16(7): 3749-3754, 2024 Feb 15.
Article in English | MEDLINE | ID: mdl-38298095

ABSTRACT

Molecular functionalization of MoS2 has attracted a lot of attention due to its potential to afford fine-tuned hybrid materials that benefit from the power of synthetic chemistry and molecular design. Here, we report on the on-surface reaction of maleimides on bulk and molecular beam epitaxy grown single-layer MoS2, both in ambient conditions as well as ultrahigh vacuum using scanning probe microscopy.

8.
ISME J ; 18(1)2024 Jan 08.
Article in English | MEDLINE | ID: mdl-38365243

ABSTRACT

Ruminants are essential for global food security, but these are major sources of the greenhouse gas methane. Methane yield is controlled by the cycling of molecular hydrogen (H2), which is produced during carbohydrate fermentation and is consumed by methanogenic, acetogenic, and respiratory microorganisms. However, we lack a holistic understanding of the mediators and pathways of H2 metabolism and how this varies between ruminants with different methane-emitting phenotypes. Here, we used metagenomic, metatranscriptomic, metabolomics, and biochemical approaches to compare H2 cycling and reductant disposal pathways between low-methane-emitting Holstein and high-methane-emitting Jersey dairy cattle. The Holstein rumen microbiota had a greater capacity for reductant disposal via electron transfer for amino acid synthesis and propionate production, catalyzed by enzymes such as glutamate synthase and lactate dehydrogenase, and expressed uptake [NiFe]-hydrogenases to use H2 to support sulfate and nitrate respiration, leading to enhanced coupling of H2 cycling with less expelled methane. The Jersey rumen microbiome had a greater proportion of reductant disposal via H2 production catalyzed by fermentative hydrogenases encoded by Clostridia, with H2 mainly taken up through methanogenesis via methanogenic [NiFe]-hydrogenases and acetogenesis via [FeFe]-hydrogenases, resulting in enhanced methane and acetate production. Such enhancement of electron incorporation for metabolite synthesis with reduced methanogenesis was further supported by two in vitro measurements of microbiome activities, metabolites, and public global microbiome data of low- and high-methane-emitting beef cattle and sheep. Overall, this study highlights the importance of promoting alternative H2 consumption and reductant disposal pathways for synthesizing host-beneficial metabolites and reducing methane production in ruminants.


Subject(s)
Euryarchaeota , Reducing Agents , Cattle , Sheep , Animals , Reducing Agents/metabolism , Methane/metabolism , Hydrogen/metabolism , Ruminants/metabolism , Fermentation , Euryarchaeota/metabolism , Rumen/metabolism
9.
Nanoscale ; 16(4): 2048-2059, 2024 Jan 25.
Article in English | MEDLINE | ID: mdl-38204411

ABSTRACT

Both at the academic and the industrial level, material scientists are exploring routes for mass production and functionalization of graphene, carbon nanotubes (CNT), carbon dots, 2D materials, and heterostructures of these. Proper application of the novel materials requires fast and thorough characterization of the samples. Raman spectroscopy stands out as a standard non-invasive technique capable of giving key information on the structure and electronic properties of nanomaterials, including the presence of defects, degree of functionalization, diameter (in the case of CNT), different polytypes, doping, etc. Here, we present a computational tool to automatically analyze the Raman spectral features of nanomaterials, which we illustrate with the example of CNT and graphene. The algorithm manages hundreds of spectra simultaneously and provides statistical information (distribution of Raman shifts, average values of shifts and relative intensities, standard deviations, correlation between different peaks, etc.) of the main spectral features defining the structure and electronic properties of the samples, as well as publication-ready graphical material.

10.
Am J Ophthalmol ; 258: 87-98, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37734639

ABSTRACT

PURPOSE: To assess factors that impact the risk of relapse in patients with noninfectious uveitis (NIU) who undergo adalimumab tapering after achieving remission. DESIGN: Retrospective study. METHODS: In this multicenter study, patients with NIU were treated with adalimumab and subsequently tapered. Patient demographics, type of NIU, onset and duration of disease, the period of inactivity before tapering adalimumab, and the tapering schedule were collected. The primary outcome measures were independent predictors of the rate of uveitis recurrence after adalimumab tapering. RESULTS: Three hundred twenty-eight patients were included (54.6% female) with a mean age of 34.3 years. The mean time between disease onset and initiation of adalimumab therapy was 35.2 ± 70.1 weeks. Adalimumab tapering was commenced after a mean of 100.8 ± 69.7 weeks of inactivity. Recurrence was observed in 39.6% of patients at a mean of 44.7 ± 61.7 weeks. Patients who experienced recurrence were significantly younger than those without recurrence (mean 29.4 years vs 37.5 years, P = .0005), and the rate of recurrence was significantly higher in younger subjects (hazard ratio [HR] = 0.88 per decade of increasing age, P = .01). The lowest rate of recurrence was among Asian subjects. A faster adalimumab taper was associated with an increased recurrence rate (HR = 1.23 per unit increase in speed, P < .0005). Conversely, a more extended period of remission before tapering was associated with a lower rate of recurrence (HR = 0.97 per 10-weeks longer period of inactivity, P = .04). CONCLUSIONS: When tapering adalimumab, factors that should be considered include patient age, race, and duration of disease remission on adalimumab. A slow tapering schedule is advisable.


Subject(s)
Inflammation , Uveitis , Humans , Female , Adult , Male , Adalimumab/therapeutic use , Retrospective Studies , Uveitis/diagnosis , Uveitis/drug therapy , Recurrence , Vision Disorders , Treatment Outcome
11.
Talanta ; 270: 125497, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38142611

ABSTRACT

In this work we present the preparation of a 2D molybdenum disulphide nanosheets (2D-MoS2) and tetrahedral DNA nanostructures (TDNs) bioconjugate, and its application to the development of a bioassay for rapid and easy virus detection. The bioconjugate has been prepared by using TDNs carrying the capture probe labelled with 6-carboxyfluoresceine (6-FAM). As case of study to assess the utility of the assay developed, we have chosen the SARS-CoV-2 virus. Hence, as probe we have used a DNA sequence complementary to a region of the SARS-CoV-2 ORF1ab gene (TDN-ORF-FAM). This 6-FAM labelled capture probe is located on the top vertex of the tetrahedral DNA nanostructure, the three left vertices of TDNs have a thiol group. These TDNs are bounded to 2D-MoS2 surface through the three thiol groups, allowing the capture probe to be oriented to favour the biorecognition reaction with the analyte. This biorecognition resulting platform has finally been challenged to the detection of the SARS-CoV-2 ORF1ab gene sequence as the target model by measuring fluorescence before and after the hybridization event with a detection limit of 19.7fM. Furthermore, due to high sensitivity of the proposed methodology, it has been applied to directly detect the virus in nasopharyngeal samples of infected patients without the need of any amplification step. The developed bioassay has a wide range of applicability since it can be applied to the detection of any pathogen by changing the probe corresponding to the target sequence. Thus, a novel, hands-on strategy for rapid pathogen detection has proposed and has a high potential application value in the early diagnosis of infections causes by virus or bacteria.


Subject(s)
Biosensing Techniques , Nanostructures , Humans , Molybdenum , DNA/chemistry , Nucleic Acid Hybridization , Nanostructures/chemistry , Sulfhydryl Compounds , Biosensing Techniques/methods
12.
Biosensors (Basel) ; 13(11)2023 Oct 27.
Article in English | MEDLINE | ID: mdl-37998133

ABSTRACT

An advanced, cost-effective, and portable DNA biosensor capable of detecting multiple bacteria simultaneously has been developed. The biosensor comprises a fast and inexpensive potentiostat that controls the applied potential to a screen-printed electrochemical array platform functionalized with MoS2 flakes and bacterial DNA probes. The current response obtained by à la carte thionine functionalized carbon nanodots (Ty-CDs) is monitored as an electrochemical indicator of the hybridization event. The design of the potentiostat prioritizes achieving an optimal signal-to-noise ratio and incorporates a user-friendly interface compatible with various devices, including computers, mobile phones, and tablets. The device is compact, lightweight, and manufactured at a low cost. The key components of the potentiostat include a data acquisition board capable of analyzing multiple samples simultaneously and a controller board. The results of this study confirm the ability of the multiplex portable biosensor to successfully detect specific bacterial DNA sequences, demonstrating its reliability and superior performance compared with a traditional, more complex, and laboratory-oriented potentiostat.


Subject(s)
Biosensing Techniques , DNA , DNA, Bacterial , Reproducibility of Results , Bacteria , Biosensing Techniques/methods , Electrochemical Techniques
14.
Ecology ; 104(12): e4174, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37776233

ABSTRACT

Habitat fragmentation remains a major focus of research by ecologists decades after being put forward as a threat to the integrity of ecosystems. While studies have documented myriad biotic changes in fragmented landscapes, including the local extinction of species from fragments, the demographic mechanisms underlying these extinctions are rarely known. However, many of them-especially in lowland tropical forests-are thought to be driven by one of two mechanisms: (1) reduced recruitment in fragments resulting from changes in the diversity or abundance of pollinators and seed dispersers or (2) increased rates of individual mortality in fragments due to dramatically altered abiotic conditions, especially near fragment edges. Unfortunately, there have been few tests of these potential mechanisms due to the paucity of long-term and comprehensive demographic data collected in both forest fragments and continuous forest sites. Here we report 11 years (1998-2009) of demographic data from populations of the Amazonian understory herb Heliconia acuminata (LC Rich.) found at Brazil's Biological Dynamics of Forest Fragments Project (BDFFP). The data set comprises >66,000 plant × year records of 8586 plants, including 3464 seedlings established after the first census. Seven populations were in experimentally isolated fragments (one in each of four 1-ha fragments and one in each of three 10-ha fragments), with the remaining six populations in continuous forest. Each population was in a 50 × 100 m permanent plot, with the distance between plots ranging from 500 m to 60 km. The plants in each plot were censused annually, at which time we recorded, identified, marked, and measured new seedlings, identified any previously marked plants that died, and recorded the size of surviving individuals. Each plot was also surveyed four to five times during the flowering season to identify reproductive plants and record the number of inflorescences each produced. These data have been used to investigate topics ranging from the way fragmentation-related reductions in germination influence population dynamics to statistical methods for analyzing reproductive rates. This breadth of prior use reflects the value of these data to future researchers. In addition to analyses of plant responses to habitat fragmentation, these data can be used to address fundamental questions in plant demography and the evolutionary ecology of tropical plants and to develop and test demographic models and tools. Though we welcome opportunities to collaborate with interested users, there are no restrictions on the use of this data set. However, we do request that those using the data for teaching or research purposes inform us of how they are doing so and cite this paper and the data archive when appropriate. Any publication using the data must also include a BDFFP Technical Series Number in the Acknowledgments. Authors can request this series number upon the acceptance of their article by contacting the BDFFP's Scientific Coordinator or E. M. Bruna.


Subject(s)
Ecosystem , Heliconiaceae , Humans , Heliconiaceae/physiology , Trees , Forests , Population Dynamics , Plants , Seedlings , Tropical Climate
15.
Rev. argent. coloproctología ; 34(3): 17-21, sept. 2023. ilus
Article in Spanish | LILACS | ID: biblio-1552492

ABSTRACT

Las lesiones obstétricas del esfínter anal pueden ocurrir durante el parto vaginal espontáneamente o secundariamente a la episiotomía. Su riesgo se estima en un 26% y son la causa más frecuente de incontinencia anal en mujeres jóvenes. Las lesiones de grado 4 de Sultan, también llamadas cloaca traumática, implican la ruptura completa del esfínter y la comunicación de la cavidad vaginal con el canal anal. La reparación es siempre quirúrgica, para lo que se han descrito diferentes técnicas, aunque ninguna ha demostrado ser superior. Presentamos el caso de una paciente primípara de 23 años con una cloaca traumática posparto. La reparación quirúrgica se realizó de inmediato con una técnica de overlapping. El postoperatorio fue sin complicaciones y al año presenta continencia anal completa. (AU)


Obstetric anal sphincter injuries can occur spontaneously or as a consequence of an episiotomy during vaginal delivery. Their risk is estimated at 26% and they are the most frequent cause of anal incontinence in young women. Sultan grade 4 injuries, also called traumatic cloaca, involve complete rupture of the sphincter and communication of the vaginal cavity with the anal canal. The repair is always surgical, for which different techniques have been described, although none have proven to be superior. We present the case of a 23-year-old primiparous patient with a postpartum traumatic cloaca. Surgical repair was performed immediately with an overlapping technique. The postoperative period was without complications and one year later she presents complete anal continence. (AU)


Subject(s)
Humans , Female , Pregnancy , Young Adult , Anal Canal/surgery , Fissure in Ano/etiology , Obstetric Labor Complications , Fecal Incontinence , Sphincterotomy/methods
16.
ACS Nano ; 17(17): 16565-16572, 2023 Sep 12.
Article in English | MEDLINE | ID: mdl-37602897

ABSTRACT

Poor individualization and interfacial adhesion prevent single-walled carbon nanotube (SWNT)-polymer composites from reaching outstanding mechanical properties. With much larger diameters, but common structural features (high aspect ratio and absence of functional groups for covalent or supramolecular attachment with the polymer), carbon fibers face similar problems, which are addressed by covering the fibers with a thin layer of polymer. This sizing strategy has allowed carbon fibers to become the filler of choice for the highest performing materials. Inspired by this, here we investigate the use of the mechanical bond to wrap SWNTs with a layer of polymeric material to produce SWNTs mechanically interlocked with a layer of polymer. We first validate the formation of mechanically interlocked nanotubes (MINTs) using mixtures of SWNTs of relatively large average diameter (1.6 ± 0.4 nm), which are commercially available at reasonable prices and therefore could be technologically relevant as polymer fillers. We then design and synthesize by ring-opening metathesis polymerization (ROMP) a polymer decorated with multiple U-shaped molecules, which are later ring-closed around the SWNTs using metathesis. The obtained hybrids contain a high degree of individualized SWNTs and exhibit significantly increased mechanical properties when compared to the matrix polymer. We envision that this strategy could be employed to produce SWNTs interlocked with polymer layers with various designs for polymer reinforcement.

17.
Medicina (B.Aires) ; 83(3): 394-401, ago. 2023. graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1506693

ABSTRACT

Resumen Introducción: En 1994, Claudio Bassi relató un caso de tratamiento médico de la necrosis pancreática infec tada (NPI); luego desde 1996 se publicaron numerosos artículos de serie de casos con tratamiento solo con antibióticos con buenos resultados. Objetivos: Presentar nuestra experiencia en el manejo de la necrosis pancreática infectada con antibióticos (sin drenaje). Métodos: Revisamos retrospectivamente los pacientes con diagnóstico de NPI desde enero de 2018 a octubre del 2020, enfocándonos en aquellos casos que se trata ron de forma conservadora (soporte hidroelectrolítico, nutricional y antibióticos). El diagnóstico se realizó ob servando gas en el retroperitoneo por TC asociado o no a deterioro clínico del paciente con necrosis pancreática sin otro foco. No se realizó punción aspiración con aguja fina (PAAF). Resultados: Identificamos 25 pacientes con diag nóstico de NPI. Once fueron tratados de forma conser vadora. Según la clasificación de Atlanta, modificada en 2012, 3 casos fueron clasificados de forma grave y el resto moderadamente grave. Todos recibieron antibióticos al menos durante 3 semanas. Ninguno requirió nutrición parenteral. El promedio de estan cia hospitalaria fue de 38 días. Tres pacientes fueron readmitidos. A 8 se les realizó colecistectomía luego de haber resuelto el cuadro; los restantes ya estaban colecistectomizados. No hubo muertes en esta serie. Conclusiones: La NPI puede ser tratada de forma con servadora sin drenaje con buenos resultados en casos seleccionados.


Abstract Introduction: In 1994, Claudio Bassi reported a case of medical treatment for infected pancreatic necrosis (IPN); then since 1996 numerous articles of case series were published with treatment only with antibiotics with good outcomes. Objectives: To present our experience in the mana gement of patients with IPN with antibiotics (without drainage). Methods: We retrospectively reviewed cases with a diagnosis of IPN from January 2018 to October 2020, focusing on those cases that were treated conservatively (hydro-electrolyte, nutritional support and antibiotics). The diagnosis was made by observing gas in the re troperitoneum by CT or by clinical deterioration of the patient with pancreatic necrosis without another focus. Fine needle aspiration was not performed. Results: We identified 25 patients with a diagnosis of IPN; eleven were treated conservatively. According to Atlanta, modified in 2012, 3 were classified severely and the rest moderately severe. All received antibiotics for at least 3 weeks. None required parenteral nutrition. The mean hospital stay was 38 days. Three patients were readmitted. 8 underwent cholecystectomy after having resolved the condition; the rest were already cholecys tectomized. There were no deaths in this series. Conclusions: IPN can be treated conservatively without drainage with good results in selected cases.

18.
Chemistry ; 29(58): e202301490, 2023 Oct 18.
Article in English | MEDLINE | ID: mdl-37452643

ABSTRACT

Single-walled carbon nanotubes (SWNTs) present extraordinary mechanical properties, with Youngs' modulus>1 TPa and tensile strength>50 GPa; this makes them ideal candidates as fillers for the reinforcement of polymers. However, the performance of SWNTs in this field has fallen behind expectations. This is due to a combination of imperfect individualization of the SWNTs and poor load transfer from the polymer to the SWNTs. Here, we study the reinforcement of polymers of different chemical nature using mechanically interlocked derivatives of single-walled carbon nanotubes (MINTs). We compare the mechanical properties of fibers made of poly (methyl methacrylate) (PMMA) and polysulfone (PSU) and their composites made with pristine SWNTs, MINTs, and the corresponding supramolecular models. With very low loading of MINTs (0.01 % w/w), improvements of more than 100 % on Youngs Modulus and the tensile strength are observed for both the nonpolar aliphatic PMMA and the very polar aromatic PSU polymers, while pristine carbon nanotubes and the supramolecular nanofillers showed smaller reinforcement. These data, together with our previous report on the reinforcement of polystyrene (nonpolar and aromatic), indicate that derivatization of SWNTs as MINTs is a valid general strategy to optimize the interaction between SWNT fillers and the polymer matrix.

19.
Medicina (B Aires) ; 83(3): 394-401, 2023.
Article in Spanish | MEDLINE | ID: mdl-37379536

ABSTRACT

INTRODUCTION: In 1994, Claudio Bassi reported a case of medical treatment for infected pancreatic necrosis (IPN); then since 1996 numerous articles of case series were published with treatment only with antibiotics with good outcomes. OBJECTIVES: To present our experience in the management of patients with IPN with antibiotics (without drainage). METHODS: We retrospectively reviewed cases with a diagnosis of IPN from January 2018 to October 2020, focusing on those cases that were treated conservatively (hydro-electrolyte, nutritional support and antibiotics). The diagnosis was made by observing gas in the retroperitoneum by CT or by clinical deterioration of the patient with pancreatic necrosis without another focus. Fine needle aspiration was not performed. RESULTS: We identified 25 patients with a diagnosis of IPN; eleven were treated conservatively. According to Atlanta, modified in 2012, 3 were classified severely and the rest moderately severe. All received antibiotics for at least 3 weeks. None required parenteral nutrition. The mean hospital stay was 38 days. Three patients were readmitted. 8 underwent cholecystectomy after having resolved the condition; the rest were already cholecystectomized. There were no deaths in this series. CONCLUSIONS: IPN can be treated conservatively without drainage with good results in selected cases.


Introducción: En 1994, Claudio Bassi relató un caso de tratamiento médico de la necrosis pancreática infectada (NPI); luego desde 1996 se publicaron numerosos artículos de serie de casos con tratamiento solo con antibióticos con buenos resultados. OBJETIVOS: Presentar nuestra experiencia en el manejo de la necrosis pancreática infectada con antibióticos (sin drenaje). Métodos: Revisamos retrospectivamente los pacientes con diagnóstico de NPI desde enero de 2018 a octubre del 2020, enfocándonos en aquellos casos que se trataron de forma conservadora (soporte hidroelectrolítico, nutricional y antibióticos). El diagnóstico se realizó observando gas en el retroperitoneo por TC asociado o no a deterioro clínico del paciente con necrosis pancreática sin otro foco. No se realizó punción aspiración con aguja fina (PAAF). RESULTADOS: Identificamos 25 pacientes con diagnóstico de NPI. Once fueron tratados de forma conservadora. Según la clasificación de Atlanta, modificada en 2012, 3 casos fueron clasificados de forma grave y el resto moderadamente grave. Todos recibieron antibióticos al menos durante 3 semanas. Ninguno requirió nutrición parenteral. El promedio de estancia hospitalaria fue de 38 días. Tres pacientes fueron readmitidos. A 8 se les realizó colecistectomía luego de haber resuelto el cuadro; los restantes ya estaban colecistectomizados. No hubo muertes en esta serie. CONCLUSIONES: La NPI puede ser tratada de forma conservadora sin drenaje con buenos resultados en casos seleccionados.


Subject(s)
Intraabdominal Infections , Pancreatitis, Acute Necrotizing , Humans , Pancreatitis, Acute Necrotizing/diagnostic imaging , Pancreatitis, Acute Necrotizing/drug therapy , Anti-Bacterial Agents/therapeutic use , Retrospective Studies , Drainage/methods , Treatment Outcome
20.
Vasc Med ; 28(4): 324-330, 2023 08.
Article in English | MEDLINE | ID: mdl-37272085

ABSTRACT

BACKGROUND: The natural history of patients with a pacemaker-related upper-extremity deep vein thrombosis (UEDVT) has not been consistently studied. METHODS: We used the RIETE registry data to compare the outcomes during anticoagulation and after its discontinuation in noncancer patients with symptomatic UEDVT associated with a pacemaker, other catheters, or no catheter. The major outcome was the composite of symptomatic pulmonary embolism or recurrent DVT. RESULTS: As of February 2022, 2578 patients with UEDVT were included: 156 had a pacemaker-related UEDVT, 557 had other catheters, and 1865 had no catheter. During anticoagulation, 61 patients (2.3%) developed recurrent VTE, 38 had major bleeding (1.4%), and 90 died (3.4%). After its discontinuation, 52 patients (4.4%) had recurrent acute venous thromboembolism (VTE) and six had major bleeding (0.5%). On multivariable analysis, there were no differences among subgroups in the rates of VTE recurrences or major bleeding during anticoagulation. After its discontinuation, patients with a pacemaker-related UEDVT had a higher risk for VTE recurrences than those with no catheter (adjusted OR: 4.59; 95% CI: 1.98-10.6). CONCLUSIONS: Patients with pacemaker-related UEDVT are at increased risk for VTE recurrences after discontinuing anticoagulation. If our findings are validated in adequately designed trials, this may justify changes in the current recommendations on the duration of anticoagulation.


Subject(s)
Neoplasms , Pulmonary Embolism , Upper Extremity Deep Vein Thrombosis , Venous Thromboembolism , Venous Thrombosis , Humans , Venous Thromboembolism/etiology , Risk Factors , Upper Extremity Deep Vein Thrombosis/diagnostic imaging , Upper Extremity Deep Vein Thrombosis/etiology , Venous Thrombosis/diagnosis , Venous Thrombosis/drug therapy , Venous Thrombosis/chemically induced , Pulmonary Embolism/chemically induced , Hemorrhage/chemically induced , Neoplasms/complications , Neoplasms/diagnosis , Anticoagulants/adverse effects , Recurrence , Extremities
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