Placebo-controlled efficacy of 5-HT3 antagonists for postoperative nausea and vomiting prophylaxis in supratentorial craniotomies: A systematic review and comparative meta-analysis of randomized clinical trials.

BACKGROUND: Postoperative nausea and vomiting (PONV) are common and distressing complications following neurosurgical procedures, affecting up to 73 % of patients undergoing craniotomy. Therefore, we aimed to assess the placebo-controlled efficacy of 5-HT3 antagonists to prevent PONV following supratentorial craniotomies. METHODS: We searched Medline, Web of Science, and Embase databases following PRISMA guidelines for RCTs comparing the outcomes of prophylactic use of 5-HT3 antagonists with placebo to prevent PONV following supratentorial craniotomy. We pooled odds ratios (OR) with 95 % confidence intervals with a random-effects model. I2 statistics was used to assess heterogeneity. RESULTS: Five RCTs, comprising 347 patients, of which 145 received a placebo, were included. The analysis identified a lower likelihood of early postoperative vomiting in 5-HT3 antagonists group (OR=0.47; 95 % CI: 0.24-0.91, p<0.05; I2=7 %), a lower likelihood of vomit within the 24-h period in 5-HT3 antagonists group (OR=0.27; 95 % CI: 0.15-0.48, p<0.01; I2=40 %), a lower likelihood of nausea within the 24-h period in 5-HT3 antagonists group (OR=0.47; 95 % CI: 0.28-0.72, p<0.01; I2=34 %), and a lower likelihood of rescue interventions in 5-HT3 antagonists group (OR = 0.18; 95 % CI: 0.10-0.34; I2 = 0 %. Subgroup analyses focusing on ondansetron also identified a lower likelihood of nausea and vomiting within the 24-h period in the 5-HT3 antagonist group. CONCLUSION: This systematic review and meta-analysis identified that 5-HT3 antagonists are effective in preventing PONV in the postoperative period following supratentorial craniotomy when compared to placebo. Our findings provide synthesized and robust evidence derived from randomized studies to support the use of 5-HT3 antagonists in clinical practice.

Gold Nanorod-Embedded PDMS Micro-Pillar Array for Localized Photothermal Stimulation.

Gold nanorods (GNRs) are one of the most promising biomaterial choices for the photothermal activation of neurons due to their relative biocompatibility, unique photothermal properties, and broad optical tunability through their synthetic shape control. While photothermal stimulation using randomly accumulated GNRs successfully demonstrates the potential treatment of functional neural disorders by modulating the neuronal activities using localized heating, there are limited demonstrations to translate this new concept into large-arrayed neural stimulations. In this paper, we report an arrayed PDMS micropillar platform in which GNRs are embedded as pixel-like, arrayed photothermal stimulators at the tips of the pillars. The proposed platform will be able to localize GNRs at predetermined pillar positions and create thermal stimulations using near-infrared (NIR) light. This will address the limitations of randomly distributed GNR-based approaches. Furthermore, a flexible PDMS pillar structure will create intimate interfaces on target cells. By characterizing the spatiotemporal temperature change in the platform with rhodamine B dye, we have shown that the localized temperature can be optically modulated within 4°C, which is in the range of temperature variation required for neuromodulation using NIR light. We envision that our proposed platform has the potential to be applied as a photothermal, neuronal stimulation interface with high spatiotemporal resolution.

Nanomechanical footprint of SARS-CoV-2 variants in complex with a potent nanobody by molecular simulations.

Rational design of novel antibody therapeutics against viral infections such as coronavirus relies on surface complementarity and high affinity for their effectiveness. Here, we explore an additional property of protein complexes, the intrinsic mechanical stability, in SARS-CoV-2 variants when complexed with a potent antibody. In this study, we utilized a recent implementation of the GoMartini 3 approach to investigate large conformational changes in protein complexes with a focus on the mechanostability of the receptor-binding domain (RBD) from WT, Alpha, Delta, and XBB.1.5 variants in complex with the H11-H4 nanobody. The analysis revealed moderate differences in mechanical stability among these variants. Also, we identified crucial residues in both the RBD and certain protein segments in the nanobody that contribute to this property. By performing pulling simulations and monitoring the presence of specific native and non-native contacts across the protein complex interface, we provided mechanistic insights into the dissociation process. Force-displacement profiles indicate a tensile force clamp mechanism associated with the type of protein complex. Our computational approach not only highlights the key mechanostable interactions that are necessary to maintain overall stability, but it also paves the way for the rational design of potent antibodies that are mechanostable and effective against emergent SARS-CoV-2 variants.

HIV-1-DNA/RNA and immunometabolism in monocytes: contribution to the chronic immune activation and inflammation in people with HIV-1.

BACKGROUND: Among people living with HIV-1 (PHIV), immunological non-responders (INR) experience incomplete immune recovery despite suppressive antiretroviral treatment (ART), facing more severe non-AIDS events than immunological responders (IR) due to higher chronic immune activation and inflammation (cIA/I). We analyzed the HIV-1 reservoir and immunometabolism in monocytes as a source of cIA/I. METHODS: Cross-sectional study in which 110 participants were enrolled: 25 treatment-naïve; 35 INR; 40 IR; and 10 healthy controls. Cell-associated HIV-1-DNA (HIV-DNA) and -RNA (HIV-RNA) were measured in FACS-isolated monocytes using digital droplet PCR. Intact, 5' deleted, and 3' deleted proviruses were quantified by the intact proviral DNA assay. Systemic inflammation, monocyte immunophenotype, and immunometabolism were characterized by immunoassays, flow cytometry, and real-time cellular bioenergetics measurements, respectively. FINDINGS: Monocytes from INR harbor higher HIV-RNA and HIV-DNA levels than IR. HIV-RNA was found in 14/21 treatment-naïve [2512 copies/106 TBP (331-4666)], 17/33 INR [240 (148-589)], and 15/28 IR [144 (15-309)], correlating directly with sCD163, IP-10, GLUT1high cells and glucose uptake, and inversely with the CD4+/CD8+ ratio. HIV-DNA was identified in all participants with detectable HIV-RNA, with intact provirus in 9/12 treatment-naïve [13 copies/106 monocytes (7-44)], 8/14 INR [46 (18-67)], and 9/13 IR [9 (7-24)]. INR presented glucose metabolism alterations and mitochondrial impairment; decreased coupling efficiency and BHI, and increased mitochondrial dysfunction inversely correlating with the CD4+/CD8+ ratio. INTERPRETATION: HIV-RNA, more than HIV-DNA, in monocytes and their altered metabolism are factors associated with the higher cIA/I that characterize INR. FUNDING: This work was supported by the European Regional Development Fund, ISCIII, grant PI20/01646. Other funding sources: Instituto de Salud Carlos III through the Subprogram Miguel Servet (CP19/00159) to AGV, PFIS contracts (FI19/00304) to EMM, (FI21/00165) to ASA, and (FI19/00083) to CGC, and a mobility grant (MV21/00103) to EMM, from the Ministerio de Ciencia e Innovación, Spain. AJM was granted by a CSL Centenary Award.

Gender Differences in Prefrontal Cortex Response to Negative Emotional Stimuli in Drivers.

BACKGROUND: Road safety improvement is a governmental priority due to driver-caused accidents. Driving style variation affects safety, with emotional regulation being pivotal. However, functional near-infrared spectroscopy (fNIRS) studies show inconsistent prefrontal cortex activity during emotion processing. This study examines prefrontal cortex response to negative emotional stimuli, particularly traffic accident images, across drivers diverse in age and gender. METHOD: The study involved 118 healthy males (44.38 ± 12.98 years) and 84 females (38.89 ± 10.60 years). The Multidimensional Driving Style Inventory (MDSI) was used to assess driving behavior alongside fNIRS recordings. Participants viewed traffic accident and neutral images while prefrontal oxygenation was monitored. RESULTS: Women rated traffic accidents (t-test = 2.43; p < 0.016) and neutral images (t-test = 2.19; p < 0.030) lower in valence than men. Arousal differences were significant for traffic accident images (t-test = -3.06; p < 0.002). correlational analysis found an inverse relationship between Dissociative scale scores and oxygenation (all p-values ≤ 0.013). Greater prefrontal oxygenation occurred with neutral images compared to traffic accidents. Left hemisphere differences (t-test = 3.23; p < 0.001) exceeded right hemisphere differences (t-test = 2.46; p < 0.015). Subgroup analysis showed male participants to be driving these disparities. Among adaptive drivers, significant oxygenation differences between neutral and accident images were evident in both hemispheres (left: t-test = 2.72, p < 0.009; right: t-test = 2.22, p < 0.030). CONCLUSIONS: Male drivers with maladaptive driving styles, particularly dissociative ones, exhibit reduced prefrontal oxygenation when exposed to neutral and traffic accident images. This response was absent in female drivers, with no notable age-related differences.

Loss of cognitive function in Mexican children due to lead exposure and the associated economic costs.

BACKGROUND: Lead exposure reduces the cognitive development and future economic prospects of children. While previous studies in high-income settings have explored productivity losses associated with lead exposure, limited research has focused on low and middle-income countries like Mexico. OBJECTIVES: This study aims to provide a comprehensive assessment of the economic implications of lead exposure on Mexican children using, for the first time, nationally representative Blood Lead Levels (BLLs) measurements in children aged 1-4, specifically focusing on the costs of forgone lifetime income due to cognitive losses. METHODS: BLLs of children aged 1-4 were extracted from the 2018-2019 National Health and Nutrition Survey (ENSANUT). Estimations of cognitive losses were derived from a log-linear relationship between BLLs and IQ loss. Lost lifetime economic productivity per child was calculated, assuming a 2% reduction in lifetime potential productivity for each IQ point lost due to lead exposure, based on previous literature (Attina and Trasande, 2013; Larsen and Sánchez-Triana, 2023). Productivity data were obtained from representative sources for Mexico. RESULTS: The estimated economic loss amounted to US $33.02 billion, equivalent to 2.76% of Mexico's Gross Domestic Product (GDP) in 2019 (calculated for a 1-year cohort). On a national scale, the long-term loss of cognition for children 1-4 years old is 4.14 IQ points per child due to lead exposure, with significant variability across States (range: 3.26 to 5.26). Lead-poisoned children (≥5 µg/dL) suffered an average loss of 6.42 IQ points (range: 0 to 6.97). In terms of economic impact, some States like Chiapas experienced losses of 7.08% of its GDP, while others had losses as low as 0.67%. Intriguingly, states with lower Human Development Index (HDIs) exhibited relatively higher economic losses despite lower average blood lead levels. DISCUSSION: The heterogeneous impact of lead exposure across Mexican states underscores the necessity for tailored regional policies. These findings emphasize the urgency for targeted interventions and informed policy measures to mitigate the socioeconomic consequences of lead exposure on Mexican children.

Comparison of 24 vs 72-hour octreotide infusion in acute esophageal variceal hemorrhage - a multi-center, randomized clinical trial.

BACKGROUND: Current guidelines lack clarity about the optimal duration of octreotide therapy for patients with esophageal variceal hemorrhage (EVH). To address this lack of evidence, we conducted a randomized clinical trial (RCT) of 24-hours versus 72-hours continuous infusion of octreotide for patients with EVH. METHODS: This multi-center, prospective RCT (NCT03624517), randomized patients with EVH to 24-hour versus 72-hour infusion of octreotide. Patients were required to undergo esophageal variceal band ligation prior to enrollment. The primary endpoint was rebleeding rate at 72 hours. The study was terminated early due to an inability to recruit during and after the COVID-19 epidemic. RESULTS: For patients randomized to 72-hours (n = 19) of octreotide vs 24-hours (n = 15), there were no differences in the need for transfusion, average pRBC units transfused per patient (3 units vs 2 units), infection (5% vs 0%), mechanical ventilation (11% vs 7%), or the need for vasopressors (5% vs 3%), respectively (none of these differences were statistically significantly different). There were 2 re-bleeding events in the 72-hour group (11%), and no re-bleeding events in the 24-hour group (p = 0.49). 8/15 of patients receiving 24 hours of octreotide were discharged at or before hospital day 3 while none in the 72-hour group was discharged before day 3 (p < 0.001). There was one death (in the 72-hour group) within 30 days. CONCLUSIONS: A 24-hour infusion is non-inferior to a 72-hour infusion of octreotide for prevention of re-bleeding in patients with EVH. We propose that shortened octreotide duration may help reduce hospital stay and related costs in these patients.

Enucleation of insulinoma using laparoscopic distal pancreatectomy with a focus on vascular and splenic preservation: a case report.

Insulinomas represent <10% of pancreatic tumors. It is a functional neuroendocrine tumor that can cause recurrent and severe episodes of loss of consciousness due to hypoglycemia. Surgical removal is the only curative treatment. The selection of the optimal surgical technique must be individualized for each patient. Currently, there are emerging innovations in less invasive techniques that reduce morbidity. We present the case of a 23-year-old woman who underwent enucleation of an insulinoma localized at the tip of the pancreatic tail after laparoscopic surgery, with a focus on vascular and splenic preservation. The tumor was safely identified during surgery and enucleated without injury to the spleen and adjacent vascular structures or postoperative complications.

Alkene Isomerization Catalyzed by a Mn(I) Bisphosphine Borohydride Complex.

An additive-free manganese-catalyzed isomerization of terminal alkenes to internal alkenes is described. This reaction is implementing an inexpensive nonprecious metal catalyst. The most efficient catalyst is the borohydride complex cis-[Mn(dippe)(CO)2(κ2-BH4)]. This catalyst operates at room temperature, with a catalyst loading of 2.5 mol %. A variety of terminal alkenes is effectively and selectively transformed into the respective internal E-alkenes. Preliminary results show chain-walking isomerization at an elevated temperature. Mechanistic studies were carried out, including stoichiometric reactions and in situ NMR analysis. These experiments are flanked by computational studies. Based on these, the catalytic process is initiated by the liberation of "BH3" as a THF adduct. The catalytic process is initiated by double bond insertion into an M-H species, leading to an alkyl metal intermediate, followed by ß-hydride elimination at the opposite position to afford the isomerization product.

Plasma concentrations of IL-6, MIP-1ß, IP-10, and PTX-3 as predictors of the immunological response to antiretroviral treatment in people with HIV.

Despite effective antiretroviral therapy (ART), 15-30% of people with HIV experience poor CD4+ T-cell recovery, termed immunologic non-responders (INR). This study aims to evaluate whether pre-ART plasma levels of interleukin-6 (IL-6), interferon gamma-induced protein-10 (IP-10), macrophage inflammatory protein-1-ß (MIP-1ß), and/or pentraxin-3 (PTX-3) could predict subsequent immunologic recovery. Seventy-four participants were enrolled and classified as INR and immunologic responders (IR) based on CD4+/CD8+ ratio increase over 24 months after starting ART. The results showed no significant differences in cytokine levels between INR and IR. Therefore, IL-6, IP-10, MIP-1ß, and PTX-3 were unsuitable as predictive markers of poor immune recovery.

Diaphragmatic rupture due to massive gastric volvulus after robotic-assisted diaphragm plication.

Gastric volvulus has been rarely associated with diaphragmatic paralysis or eventration. In this article, we present the case of a patient with idiopathic paralysis of the left hemidiaphragm that underwent treatment with a robotic thoracoscopic diaphragm plication, which was complicated by massive gastric volvulus resulting in such significant intra-abdominal hypertension that the ipsilateral diaphragm ruptured anterior to the plication suture line.

An Unlikely Case of Blastomycosis in an Elderly Female: A Diagnostic Challenge in a Non-endemic Region.

Blastomyces dermatitidis is a fungus typically found in the soil of endemic regions such as the Midwest, concentrating in areas like Ohio, Mississippi, and the Great Lakes area. The systemic infection caused by inhaling Blastomyces dermatitidis is known as blastomycosis. The frequency of blastomycosis in non-endemic regions is increasing for a variety of speculated reasons, such as higher rates of immunosuppressed individuals and possible climate. Due to clinician unfamiliarity, misdiagnosis of blastomycosis is common, which potentiates worsening systemic infections. This study shows the clinical course of a patient with blastomycosis in a non-endemic region, highlighting the need for education for clinicians in non-endemic areas. A 72-year-old female with a history of chronic obstructive pulmonary disease (COPD), coronary artery disease, a 47-year smoking history, and hypertension presented for outpatient management of COPD. CT three months prior to presentation showed nodular opacities in the lungs. A bronchoscopy was performed and revealed negative findings for malignancy or infection; the patient developed worsening symptoms leading to hospitalization. Subsequent testing revealed Blastomyces dermatitidis. She was promptly treated with a six to 12-month course of itraconazole with close follow-up. The study highlights the need not to rule out causes of infection based on location. Blastomycosis can resemble community-acquired pneumonia. Making the correct diagnosis is paramount, as delays can result in morbidity. Fungal cultures may be the gold standard, but due to the long culture time, there need to be other diagnostic tests like urine antigen testing. This study highlights the need to increase awareness of clinicians who experience blastomycosis patients in a non-endemic region.

Widespread geographic distribution of Aedes aegypti (Diptera: Culicidae) kdr variants in Panama.

We searched for evidence of knockdown resistance (kdr) mutations in the voltage-gated sodium channel gene of Aedes aegypti (Linnaeus) (Diptera: Culicidae) and Aedes albopictus (Skuse) (Diptera: Culicidae) mosquitoes from Panama. Conventional PCR was performed on 469 Ae. aegypti and 349 Ae. albopictus. We did not discover kdr mutations in Ae. albopictus, but 2 nonsynonymous kdr mutations, V1016I (found in 101 mosquitoes) and F1534C (found in 29 of the mosquitoes with the V1016I), were detected in Ae. aegypti. These kdr mutations were present in all specimens that were successfully sequenced for both IIS5-S6 and IIIS6 regions, which included samples collected from 8 of the 10 provinces of Panama. No other kdr mutations were found in Ae. aegypti, including V1016G, which has already been reported in Panama. Findings suggest that the V1016I-F1534C variant is prevalent in Panama, which might be related to the introduction and passive movement of mosquitoes as part of the used-tire trade. However, we cannot rule out the possibility that selection on de novo replacement of kdr mutations also partially explains the widespread distribution pattern of these mutations. These 2 ecological and evolutionary processes are not mutually exclusive, though, as they can occur in tandem. Research in Panama needs to calculate the genotypic and allelic frequencies of kdr alleles in local Ae. aegypti populations and to test whether some combinations confer phenotypic resistance or not. Finally, future studies will have to track the introduction and spreading of new kdr mutations in both Aedes species.

Challenges associated with low rectal malignant obstruction stenting: a case report.

An ongoing debate exists regarding the feasibility of placing self-expanding metallic stents (SEMS) within 5 cm of the anal verge. Traditionally, SEMS have been considered contraindicated for patients with a malignant rectal obstruction within this region due to potential impact on the anorectal ring or anal canal, which can cause incontinence, proctalgia, and tenesmus. However, in the case of a 63-year-old female who presented with distention, abdominal pain, and diminishing stool output, the rectal exam identified a bulky fixed mass. Imaging studies revealed large bowel obstruction and high-grade stricture, with a minuscule residual lumen. Endoscopy identified a bulky mass obscuring the lumen at 5 cm from the anal verge, and biopsy confirmed adenocarcinoma. Despite the traditionally held contraindication, a 2.5 cm × 9.0 cm colonic stent was successfully deployed, leading to brisk colonic decompression. This allowed the patient to promptly undergo chemoradiotherapy.

Evaluation and imaging of biodistribution of magnetic nanoparticles in a model of hepatic cirrhosis via alternating current biosusceptometry.

In recent years, magnetic nanoparticles (MNPs) have exhibited theragnostic characteristics which confer a wide range of applications in the biomedical field. Consequently, through Alternating Current Biosusceptometry (ACB), magnetic nanoparticles can be used as tracers, allowing the study of healthy and cirrhotic livers and providing the ability to differentiate them through the reconstruction of quantitative images. The ACB system consists of a developing biomagnetic technique that has the ability to magnetize and measure the magnetic susceptibility of a material such as MNPs, thereby offering quantitative information about biological systems with magnetic tracers.

Unraveling the ecological niche signals of Verticillium dahliae: Insights from Mediterranean landscapes.

Verticillium wilt (VW), caused by the soil-borne plant pathogenic fungus Verticillium dahliae, is a major disease impacting olive crops globally. In view of the lack of effective post-infection treatments, exclusion and avoidance strategies are essential in disease management. Assessing the risks posed by this pathogen is essential to prevent the spread and to ensure selection of suitable sites for new plantations. This study aimed to elucidate the environmental factors driving V. dahliae establishment in the Andalusia region, in southern Spain, an emblematic Mediterranean landscape for olive cultivation. To this end, we explored ecological niche signals for this fungal pathogen by analyzing 62 environmental variables across 1.6 million hectares dedicated to olive and cotton cultivation, using a 15-yr survey data on VW incidence on presence-absence from both olive and cotton fields. To ensure robust identification of ecological niche signals, we employed randomization-based, non-parametric univariate tests to compare presence records with the broader sampling universe (including absence records). Our findings identified key environmental variables that are associated significantly with V. dahliae presence, including temperature range seasonality (including mean diurnal and annual ranges), summer temperature (maximum of the warmest month, mean of the warmest quarter), and moisture and water availability (near-surface humidity, potential evapotranspiration, vapor pressure) as core niche variables for V. dahliae. Our results replicated the pathogen's known distribution, identifying the Guadalquivir Valley as a particularly high-risk area in view of its mild winters and distinct rainy seasons, providing new insights into the specific environmental conditions that facilitate the pathogen's survival and spread. Furthermore, this study introduces a novel approach to niche modeling that prioritizes variables with consistent effects and significant impact on the presence and distribution of V. dahliae and identifies potential data artifacts. This approach enhances our understanding of ecological requirements in V. dahliae and informs targeted management strategies.

Hardware-Efficient Configurable Ring-Oscillator-Based Physical Unclonable Function/True Random Number Generator Module for Secure Key Management.

The use of physical unclonable functions (PUFs) linked to the manufacturing process of the electronic devices supporting applications that exchange critical data over the Internet has made these elements essential to guarantee the authenticity of said devices, as well as the confidentiality and integrity of the information they process or transmit. This paper describes the development of a configurable PUF/TRNG module based on ring oscillators (ROs) that takes full advantage of the structure of modern programmable devices offered by Xilinx 7 Series families. The proposed architecture improves the hardware efficiency with two main objectives. On the one hand, we perform an exhaustive statistical characterization of the results derived from the exploitation of RO configurability. On the other hand, we undertake the development of a new version of the module that requires a smaller amount of resources while considerably increasing the number of output bits compared to other proposals previously reported in the literature. The design as a highly parameterized intellectual property (IP) module connectable through a standard interface to a soft- or hard-core general-purpose processor greatly facilitates its integration into embedded solutions while accelerating the validation and characterization of this element on the same electronic device that implements it. The studies carried out reveal adequate values of reliability, uniqueness, and unpredictability when the module acts as a PUF, as well as acceptable levels of randomness and entropy when it acts as a true random number generator (TRNG). They also illustrate the ability to obfuscate and recover identifiers or cryptographic keys of up to 4096 bits using an implementation of the PUF/TRNG module that requires only an array of 4×4 configurable logic blocks (CLBs) to accommodate the RO bank.

Acute necrotizing pancreatitis caused by ampullary cancer: a case report.

Ampullary malignancies are extremely rare tumors that are usually diagnosed when they cause biliary obstruction. Rarely, any tumor or mass near or within the pancreas can cause acute pancreatitis and on even rarer occasions, these tumors can cause severe complications such as acute peripancreatic fluid collections, necrotizing pancreatitis, and infections. As a medical team, we must embrace these difficulties and these dreadful scenarios, as they are opportunities for growth for the medical team and opportunities to save even more patients. We present the case of a 59-year-old male who suddenly presented acute severe pancreatitis with necrosis and infection due to an ampullary mass. After recovery, he was referred to a tertiary center, where his cancer was successfully treated.

Regrowth dynamics and morpho-physiological characteristics of Plantago lanceolata under different defoliation frequencies and intensities.

Traditional pastures in temperate regions face limitations such as reduced growth and nutritional quality during the summer season. Plantain (P. lanceolata L.) offers advantages like increased yield and decreased nitrogen losses from grazing ruminants. Effective grazing management is essential for pasture health, and defoliation frequency and intensity play a pivotal role. This study aimed to evaluate plantain's regrowth, yield, and morpho-physiological and chemical responses under different defoliation frequencies and intensities, with the goal of enhancing its management in pastures. The study was conducted in pots within a controlled-environment growth chamber, examining the impact of three defoliation frequencies (based on extended leaf length: 15, 25 and 35 cm) and two defoliation intensities (5 and 8 cm of residual heights) with four replicates (24 pots as experimental units). The variables of interest were morphological characteristics, dry matter (DM) accumulation, herbage chemical composition, growth rate traits, and photosynthetic parameters. Defoliation frequency affected plantain's growth and nutritional composition. More frequent cuts (15 cm) resulted in lower DM yield per cut and lower stem content, while less frequent cuts (35 cm) produced higher values. Defoliation intensity influenced the proportion of leaves and stems in the total DM, with 5 cm cuts favoring leaves. Nutrient content was also affected by defoliation frequency, with less frequent cuts (35 cm) showing lower crude protein concentration and metabolizable energy content but higher neutral detergent fiber and water-soluble carbohydrate concentration. Plantain's growth rate variables were mainly influenced by defoliation frequency, with less frequent cuts promoting faster leaf appearance and growth of new leaves. The basal fluorescence variables and chlorophyll content were affected by cutting frequency, being highest when cut less frequently (35 cm), while no differences were found in the actual quantum efficiency among different defoliation frequencies and intensities. The fraction of light dedicated to non-photochemical quenching was highest when cut less frequently and more intensively. Overall, defoliation at 25 cm of extended leaf length balanced plantain forage quality and regrowth capacity.