RESUMEN

BACKGROUND AND OBJECTIVES: Markers of white matter (WM) injury on brain MRI are important indicators of brain health. Different patterns of WM atrophy, WM hyperintensities (WMHs), and microstructural integrity could reflect distinct pathologies and disease risks, but large-scale imaging studies investigating WM signatures are lacking. This study aims to identify distinct WM signatures using brain MRI in community-dwelling adults, determine underlying risk factor profiles, and assess risks of dementia, stroke, and mortality associated with each signature. METHODS: Between 2005 and 2016, we measured WMH volume, WM volume, fractional anisotropy (FA), and mean diffusivity (MD) using automated pipelines on structural and diffusion MRI in community-dwelling adults aged older than 45 years of the Rotterdam study. Continuous surveillance was conducted for dementia, stroke, and mortality. We applied hierarchical clustering to identify separate WM injury clusters and Cox proportional hazard models to determine their risk of dementia, stroke, and mortality. RESULTS: We included 5,279 participants (mean age 65.0 years, 56.0% women) and identified 4 distinct data-driven WM signatures: (1) above-average microstructural integrity and little WM atrophy and WMH; (2) above-average microstructural integrity and little WMH, but substantial WM atrophy; (3) poor microstructural integrity and substantial WMH, but little WM atrophy; and (4) poor microstructural integrity with substantial WMH and WM atrophy. Prevalence of cardiovascular risk factors, lacunes, and cerebral microbleeds was higher in clusters 3 and 4 than in clusters 1 and 2. During a median 10.7 years of follow-up, 291 participants developed dementia, 220 had a stroke, and 910 died. Compared with cluster 1, dementia risk was increased for all clusters, notably cluster 3 (hazard ratio [HR] 3.06, 95% CI 2.12-4.42), followed by cluster 4 (HR 2.31, 95% CI 1.58-3.37) and cluster 2 (HR 1.67, 95% CI 1.17-2.38). Compared with cluster 1, risk of stroke was higher only for clusters 3 (HR 1.55, 95% CI 1.02-2.37) and 4 (HR 1.94, 95% CI 1.30-2.89), whereas mortality risk was increased in all clusters (cluster 2: HR 1.27, 95% CI 1.06-1.53, cluster 3: HR 1.65, 95% CI 1.35-2.03, cluster 4: HR 1.76, 95% CI 1.44-2.15), compared with cluster 1. Models including clusters instead of an individual imaging marker showed a superior goodness of fit for dementia and mortality, but not for stroke. DISCUSSION: Clustering can derive WM signatures that are differentially associated with dementia, stroke, and mortality risk. Future research should incorporate spatial information of imaging markers.

Asunto(s)

RESUMEN

INTRODUCTION: Periampullary cancer has a poor prognosis. Surgical resection is a potentially curative but high-risk treatment. Comprehensive geriatric assessment (CGA) can inform treatment decisions, but has not yet been evaluated in older patients eligible for pancreatic surgery. METHODS: This prospective observational study included patients ≥ 70 years of age eligible for pancreatic surgery. Frailty was defined as impairment in at least two of five domains: somatic, psychological, functional, nutritional, and social. Outcomes included postoperative complications, functional decline, and mortality. RESULTS: Of the 88 patients included, 87 had a complete CGA. Sixty-five patients (75%) were frail and 22 (25%) were non-frail. Frail patients were more likely to receive nonsurgical treatment (43.1% vs. 9.1% p = 0.004). Fifty-seven patients underwent surgery, of which 52 (59%) underwent pancreaticoduodenectomy. The incidence of postoperative delirium was three times higher in frail patients (29.7% vs. 0%, p = 0.005). The risk of mortality was three times higher in frail patients (HR: 3.36, 95% CI: 1.43-7.89, p = 0.006). CONCLUSION: Frailty is common in older patients eligible for pancreatic surgery and is associated with treatment decision, a higher incidence of delirium and a three times higher risk of all-cause mortality. CGA can contribute to shared decision-making and optimize perioperative care in older patients.

RESUMEN

In 2016, the Bloomberg Philanthropies Data for Health initiative assisted the Philippine Statistical Authority in implementing Iris, an automated coding software program that enables medical death certificates to be coded according to international standards. Iris was implemented to improve the quality, timeliness, and consistency of coded data as part of broader activities to strengthen the country's civil registration and vital statistics system. This study was conducted as part of the routine implementation of Iris to ensure that automatically coded cause of death data was of sufficient quality to be released and disseminated as national mortality statistics. Data from medical death certificates coded with Iris between 2017 and 2019 were analysed and evaluated for apparent errors and inconsistencies, and trends were examined for plausibility. Cause-specific mortality distributions were calculated for each of the 3 years and compared for consistency, and annual numeric and percentage changes were calculated and compared for all age groups. The typology, reasons, and proportions of records that could not be coded (Iris 'rejects') were also studied. Overall, the study found that the Philippine Statistical Authority successfully operates Iris. The cause-specific mortality fractions for the 20 leading causes of death showed reassuring stability after the introduction of Iris, and the type and proportion of rejects were similar to international experience. Broadly, this study demonstrates how an automated coding system can improve the accuracy and timeliness of cause of death data-providing critical country experiences to help build the evidence base on the topic.

Asunto(s)

RESUMEN

Background: Peyronie's disease (PD) is a localized fibrosis of tunica albuginea, which causes the anatomical and functional changes to the penis. Corporoplasty with grafting is indicated in severe (>60°) and complex curvature. Buccal mucosa is the most favored autologous graft material nowadays. The ventrolateral aspect of lingual mucosa has similar histological features to the rest of the oral cavity. Methods: This study aimed to test the efficacy, safety, durability, and reproducibility of corporoplasty with lingual mucosal graft (LMG) in the surgical treatment of PD in terms of surgical outcome, sexual function, and donor site complications. This prospective study included 19 patients of PD with severe and complex curvature, who underwent corporoplasty with LMG. Surgical and functional outcomes were assessed at follow-up planned at 2 weeks, 3 months, 6 months, 1 year, and 2 years. Results: The mean operative time was 126.31 ± 21.45 min. Additional Nesbit's plication to correct the residual deformity was required in 26% (5 / 19) of patients. Straightening of the penis (curvature <10°) was achieved in 89% (17 / 19) of patients. Increase in the penile length (>1 cm) postoperatively was achieved in 63% (12 / 19) of patients and a shortening of penis occurred in 5% (1 / 19) of patients. Newer onset erectile dysfunction developed in 11% (2 / 19) of patients, and patient and partner satisfaction rates were 89% (17 / 19) and 84% (16 / 19), respectively, in a mean follow-up of 20.66 ± 5.37 months. Donor site complications were minimal and no patient had any salivary changes or speech disturbances. Conclusion: LMG provided excellent short-term results in terms of deformity correction, improved sexual function, and minimal donor site morbidity. The method is simple and reproducible, and multicenter studies with larger number of cases with longer follow-up are required to confirm these favorable results.

RESUMEN

Accurate sleep stage classification is significant for sleep health assessment. In recent years, several machine-learning based sleep staging algorithms have been developed, and in particular, deep-learning based algorithms have achieved performance on par with human annotation. Despite improved performance, a limitation of most deep-learning based algorithms is their black-box behavior, which have limited their use in clinical settings. Here, we propose a cross-modal transformer, which is a transformer-based method for sleep stage classification. The proposed cross-modal transformer consists of a cross-modal transformer encoder architecture along with a multi-scale one-dimensional convolutional neural network for automatic representation learning. The performance of our method is on-par with the state-of-the-art methods and eliminates the black-box behavior of deep-learning models by utilizing the interpretability aspect of the attention modules. Furthermore, our method provides considerable reductions in the number of parameters and training time compared to the state-of-the-art methods. Our code is available at https://github.com/Jathurshan0330/Cross-Modal-Transformer. A demo of our work can be found at https://bit.ly/Cross_modal_transformer_demo.

Asunto(s)

RESUMEN

PURPOSE: Recent studies have reported the use of the obstetric-specific quality of recovery tool (ObsQoR-10) to assess the quality of recovery in parturients after childbirth; however, the correlation between ObsQoR-10 scores and important postpartum outcomes are unclear. The primary aim of the present study was to investigate the correlations between ObsQoR-10 scores at 24 hr after Cesarean delivery and breastfeeding, depressive symptomatology, overall health, and pain at seven days postpartum. METHODS: We recruited parturients who underwent elective Cesarean delivery at KK Hospital in Singapore. Parturients provided responses to post-Cesarean questionnaires at 1) 24 hr (ObsQoR-10, EuroQol EQ-Visual Analogue Scale, Edinburgh Postnatal Depression Scale), 2) 48 hr (ObsQoR-10, EQ-Visual Analogue Scale), and 3) seven days after Cesarean delivery (ObsQoR-10, Breastfeeding Self-Efficacy Scale-Short form, EQ-Visual Analogue Scale, Edinburgh Postnatal Depression Scale, pain survey). RESULTS: We enrolled 222 participants, 200 (90%) of whom completed the seven-day follow-up between September 2022 and April 2023. There was limited correlation between ObsQoR-10 at 24 hr with the Edinburgh Postnatal Depression Scale (r = 0.135), EQ-Visual Analogue Scale (r = 0.158), Breastfeeding Self-Efficacy Scale-Short form (r = 0.225), and averaged pain scores (r = -0.107) at seven days postpartum. ObsQoR-10 breastfeeding sub-score at 24 hr was weakly correlated with Breastfeeding Self-Efficacy Scale-Short form at seven days postpartum (r = 0.307). CONCLUSION: ObsQoR-10 at 24 hr postpartum had limited correlation with breastfeeding, depressive symptomatology, overall health, and pain at seven days. STUDY REGISTRATION: ClinicalTrials.gov ( NCT04989894 ); first submitted 4 July 2021.

RéSUMé: OBJECTIF: Des études récentes ont rapporté l'utilisation de l'outil de qualité de récupération spécifique à l'obstétrique (ObsQoR-10) pour évaluer la qualité de la récupération chez les personnes parturientes après l'accouchement; cependant, la corrélation entre les scores sur l'outil ObsQoR-10 et les devenirs post-partum importants n'est pas claire. L'objectif principal de la présente étude était d'examiner les corrélations entre les scores ObsQoR-10 obtenus 24 heures après l'accouchement par césarienne et l'allaitement, la symptomatologie dépressive, l'état de santé général et la douleur sept jours après l'accouchement. MéTHODE: Nous avons recruté des personnes parturientes qui ont bénéficié d'un accouchement par césarienne programmée à l'Hôpital KK de Singapour. Les personnes parturientes ont répondu aux questionnaires post-césarienne à 1) 24 heures (ObsQoR-10, échelle visuelle analogique EuroQol EQ-Visual Analogue Scale, Échelle de dépression postnatale d'Édimbourg), 2) 48 heures (ObsQoR-10, EQ-Visual Analogue Scale), et 3) sept jours après la césarienne (ObsQoR-10, Échelle abrégée d'auto-efficacité de l'allaitement [Breastfeeding Self-Efficacy Scale-Short form], EQ-Visual Analogue Scale, Échelle de dépression postnatale d'Edimbourg, enquête sur la douleur). RéSULTATS: Nous avons recruté 222 participant·es, dont 200 (90 %) ont terminé le suivi de sept jours entre septembre 2022 et avril 2023. Il y avait une corrélation limitée entre l'ObsQoR-10 à 24 heures et l'Échelle de dépression postnatale d'Édimbourg (r = 0,135), l'échelle EQ-Visual Analogue Scale (r = 0,158), l'échelle d'auto-efficacité de l'allaitement maternel forme courte (r = 0,225) et les scores moyens de douleur (r = -0,107) sept jours après l'accouchement. Le sous-score d'allaitement ObsQoR-10 à 24 heures était faiblement corrélé à l'échelle d'auto-efficacité de l'allaitement maternel à sept jours après l'accouchement (r = 0,307). CONCLUSION: L'ObsQoR-10 à 24 heures après l'accouchement avait une corrélation limitée avec l'allaitement, la symptomatologie dépressive, l'état de santé général et la douleur à sept jours. ENREGISTREMENT DE L'éTUDE: ClinicalTrials.gov ( NCT04989894 ); première soumission le 4 juillet 2021.

Asunto(s)

RESUMEN

Cancers arising from the gingivobuccal complex are one of the most common types of cancer in the oral cavity and are associated with poor prognosis. Among the various prognostic factors, positive surgical margin is the most important one that can be controlled by the operating surgeon. The deep surgical margins for buccal mucosa cancers is normally assessed by palpating the skin for induration and skin pinchability. The present study evaluates the role of imaging in assessing the deep surgical margin and its efficacy for skin preservation in buccal mucosa/ gingivobuccal carcinomas. The patients of gingivobuccal complex squamous cell carcinomas after histopathological confirmation were selected for the study. In imaging, the distance between the base of the tumour and skin (epidermis) of the cheek was measured by a senior radiologist preoperatively. The frozen section findings were confirmed by histopathological examination and the depth of invasion of the tumour was measured and the clearance of the deep surgical margin was confirmed. The correlation between imaging, skin pinch test and histopathological examination of the specimen was assessed. The sensitivity and specificity of imaging to predict the skin preservation (deep surgical margin more than 5 mm) is 100% and 75% respectively compared to sensitivity and specificity of skin pinch test of 82.6% and 50% respectively. Imaging is an effective tool in predicting the skin preservation and skin excision compared to skin pinch test. Compared to the skin pinch test, imaging appears to be a useful tool for advising surgeons on skin preservation vs excision.

RESUMEN

CARDS is a database that contains information on federally funded research projects related to dietary supplements. It includes projects funded by the United States Department of Agriculture (USDA), the Department of Defense (DOD), and the Institutes and Centers (ICs) of the National Institutes of Health (NIH), beginning from the fiscal year 1999, the first year federal agencies started reporting research related to dietary supplements. It is provides detailed records of research projects funded by these federal agencies. It serves as an resource for tracking the progress and outcomes of dietary supplement research funded by the government.

Asunto(s)

RESUMEN

The Dietary Supplement Ingredient Database (DSID) provides estimated levels of ingredients in dietary supplement products sold in the United States. These estimates, which are based on chemical analysis of nationally representative products, may differ from the labeled amounts. The DSID offers data for understanding the actual content of dietary supplements, supporting research, regulation, and consumer awareness regarding the accuracy and quality of supplement ingredients.

Asunto(s)

RESUMEN

DTP’s Natural Products Repository is a storehouse of natural products. It houses extracts from samples of plants and marine organisms collected from more than 25 countries andextracts of diverse bacteria and fungi. Access to this Repository will be subject to meeting the conditions and signing a Material Transfer Agreement (pdf file for download) protecting the rights of all parties.

Asunto(s)

RESUMEN

The chemical structure of piperidine has a unique ability to combine with other molecular fragments. This fact makes it possible to actively use it as an effective basis for the creation of new drug-like substances. Thus, the aim of the current investigation was to study the acute toxicity, local anesthetic potency, and antiarrhythmic activity of the two new synthesized piperidine derivatives under laboratory codes LAS-286 and LAS-294 (local anesthetic substances). The Bulbring & Wajda animal model and method of determining the nociception threshold during electrical stimulation was used to investigate the action of the substance during infiltration anesthesia. An antiarrhythmic activity was observed by the aconitine-induced rat arrhythmia model. Additionally, these compounds were studied in relation to molecular docking to delineate the structure-activity relationships. The tested piperidine derivatives had a low toxicity in the subcutaneous and intravenous administration routes. The experimental results showed a higher prolonged and pronounced local anesthetic activity for LAS-286 at a 0.5% concentration, compared to the reference preparations. The low dosage of 0.1 mg/kg of LAS-294 demonstrated a pronounced preventive antiarrhythmic effect in 90% of cases on the development of mixed arrhythmia, caused by aconitine. The results of molecular docking confirmed a higher binding affinity of the tested piperidines with the Nav1.4 and Nav1.5 macromolecules. The results of the present study are very promising, because these piperidines have shown a high biological activity, which can suggest a potential therapeutic application in the future.

Asunto(s)

Asunto(s)

RESUMEN

In 1987, Won invented the solid-phase porous microsphere (MS), which stores bioactive compounds in many interconnected voids. Spherical particles (5-300 µm), MS, may form clusters of smaller spheres, resulting in many benefits. The current investigation focussed on gel-encased formulation, which can be suitable for dermal usage. First, quasi-emulsion (w/o/w) solvent evaporation was used to prepare 5-fluorouracil (5 FU) MS particles. The final product was characterized (SEM shows porous structure, FTIR and DSC showed drug compatibility with excipients, and gel formulation is shear-thinning) and further scaled up using the 8-fold method. Furthermore, CCD (Central Composite Design) was implemented to obtain the optimized results. After optimizing the conditions, including the polymer (600 mg, ethyl cellulose (EC), eudragit RS 100 (ERS)), stirring speed (1197 rpm), and surfactant concentration (2% w/v), we achieved the following results: optimal yield (63%), mean particle size (152 µm), drug entrapment efficiency (76%), and cumulative drug release (74.24% within 8 h). These findings are promising for industrial applications and align with the objectives outlined in UN Sustainable Development Goals 3, 9, and 17, as well as the goals of the G20 initiative.

Asunto(s)

RESUMEN

BACKGROUND: The serum progesterone (P4) level during the luteal phase (LP) plays a crucial role in the initiation and maintenance of pregnancy. However, it is unclear whether the natural cycle consistently provides the best endocrine profile and whether mid-luteal serum P4 levels are always sufficient to support implantation and early pregnancy. The question has become more relevant in relation to fertility treatment, as more frozen embryo transfer cycles are performed in the natural cycle. Moreover, can serum hormone levels and covariates measured during the follicular phase (FP), such as Follicle Stimulation Hormone (FSH), Luteinizing Hormone (LH), Estradiol (E2), Anti-Mullerian Hormone (AMH) and Antral Follicle Count (AFC), be used to predict P4 levels during the luteal phase (LP)? RESULTS: This observational prospective cohort study analysed 26 healthy women with a cycle length between 21-35 days and a body mass index (BMI) < 30 kg/m2. Blood sampling started on the fifth day of the menstrual cycle and continued every fifth day until the next cycle. The procedure was repeated for a total of three cycles. The study found that only ten women had a P4 level greater than 30 nmol/L on cycle day 20 or 25 in all three cycles. In total, only 45 cycles out of 77 cycles had serum P4 levels ≥ 30 nmol/L. The E2 level ≥ 345 pmol/L on cycle day 10 proved to be predictive of a P4 level of ≥ 30 nmol/L on either day 20 or day 25 with a sensitivity of 57% and a specificity of 89%. No other covariates, including the FSH level cycle day 5, LH levels during the follicular phase, age, weight, AFC and AMH cycle day 5 correlated with LP P4 levels. CONCLUSIONS: A significant correlation between FP E2 levels cycle day 5 (> 131pmol/L) and cycle day 10 (> 345pmol/L) and a LP P4 level ≥ 30 nmol/l was found; thus, the FP E2 level is a predictor of corpus luteum competence. Our findings highlight the existence of suboptimal P4 levels during the LP and a significant inter-individual and intra-cycle variation in P4 levels during the LP in regular menstruating women.

Asunto(s)

RESUMEN

Biosensing plays a pivotal role in various scientific domains, offering significant contributions to medical diagnostics, environmental monitoring, and biotechnology. Fluorescence biosensing relies on the fluorescence emission from labelled biomolecules to enable sensitive and selective identification and quantification of specific biological targets in various samples. Photonic crystal fibers (PCFs) have led to the development of optofluidic fibers enabling efficient light-liquid interaction within small liquid volume. Herein, we present the development of a user-friendly optofluidic-fiber platform with simple hardware requirements for sensitive and reliable fluorescence biosensing with high measurement repeatability. We demonstrate a sensitivity improvement of the fluorescence emission up to 17 times compared to standard cuvette measurement, with a limit of detection of Cy5 fluorophore as low as 100 pM. The improvement in measurement repeatability is exploited for detecting haptoglobin protein, a relevant biomarker to diagnose several diseases, by using commercially available Cy5 labelled antibodies. The study aims to showcase an optofluidic platform leveraging the benefits provided by optofluidic fibers, which encompass easy light injection, robustness, and high sensitivity.

RESUMEN

BACKGROUND: Intensity modulated radiotherapy (IMRT) has become a standard radiotherapy treatment delivery option owing to the advantages it offers in terms of target coverage and organ sparing. Furthermore, the ability to introduce different fractionation for different targets lets us deliver higher doses to the high-risk areas and lower doses to the elective volumes at the same sitting, referred to as simultaneous integrated boost (SIB). In the current study, we intended to retrospectively analyze the clinical outcomes and patterns of the failure of oropharyngeal cancers treated with SIB-IMRT and concurrent chemotherapy at our centre and analyze the factors contributing to poorer outcomes. MATERIAL AND METHODS: Data of oropharyngeal cancer patients treated with SIB-IMRT and concurrent chemotherapy were retrieved from the institutional database. Patient demographic details, histopathological features, staging, treatment details, failure patterns and outcomes were documented. All potential factors were evaluated for outcomes. Radiation was delivered by using the SIB-IMRT technique. High-risk planning target volume (PTV) received 66 Gy in 2.2 Gy/fraction, intermediate and low-risk PTV received 60 Gy and 54 Gy, respectively. Primary endpoint was to assess local control (LC), regional control (RC) and loco-regional control (LRC) rates and secondary end point was to evaluate the survival outcomes - overall survival (OS) and cancer-specific mortality. All survival analyzes were performed using the Kaplan-Meier method. RESULTS: A total of 169 cases were included in the final analysis. The median age was 55 years (range 20-78) with 95.3% males. The base of tongue was the most common primary site. Around 54% cases were node negative with 38% patients having stage IV disease. The local control rates for N0 vs. N+ cases were 74.1 vs. 62.3% (P = 0.046), respectively. Similarly, the 4-year RC rates for N0 vs. N+ cases were 94.4 vs. 83.5% (P = 0.024), respectively. On multivariate analysis, only 4-year RC rates showed significant difference between the two (P = 0.039). No differences were found between T stages in LRC and OS. The 4-year LRC rates for stages 1, 2 vs. 3, 4 were non-significant (69.2 vs. 66.3%; P = 0.178). The 4-year OS rate was 81.3%. The 4-year LC and LRC rates were 67.8 and 89.5%, respectively. There were 54 local and 17 regional failures. The median time to failure was 13 months (range 3.6-82.9). CONCLUSION: SIB-IMRT provides comparable outcomes for oropharyngeal cancers. OS and loco-regional recurrences were significantly worse for nodal positive disease.

Asunto(s)

RESUMEN

BACKGROUND: Tracheostomy is an important life-saving surgical procedure that could be used to secure the lower airway. It can however serve as a source of airway compromise when fragments from it are deposited. This condition must be diagnosed early enough, and appropriate intervention should be done to forestall potential morbidity and mortality. CASE REPORT: A 56-year-old tracheostomized patient presented to the accident and emergency department with a 4-hour history of sudden onset choking cough and labored breathing. The shaft of his tracheostomy tube (TT) was fractured and subsequently aspirated while he was attempting to remove and clean the inner tube that morning. He has used the TT for about 6 years and lost to follow-up clinic visits. The chest radiograph showed the metallic foreign body lodged within the trachea. He had an emergency rigid bronchoscopy via the tracheostomy stoma, and the object was retrieved. All respiratory symptoms subsequently resolved, and a check radiograph showed normal findings. CONCLUSION: Tracheostomy tube fracture and aspiration should be ruled out in every tracheostomized patient with sudden onset acute respiratory symptoms. Otolaryngologists must always emphasize the need for proper handling of TT, regular follow-up, and tube replacement when due.

Asunto(s)

RESUMEN

The objective of this study was to analyze the in vitro antimicrobial resistance (AMR) of Streptococcus (Sc.) dysgalactiae, Sc. agalactiae, and Sc. canis over a 10-year period from 2012 to 2022 against the most commonly used antimicrobial agents. For this purpose, all quarter milk samples (QMS) submitted to the milk laboratory of the Bavarian Animal Health Service (TGD) were analyzed. Each QMS was tested using the California Mastitis Test (CMT) and categorized as negative (N), subclinical (S), or clinical (C) mastitis if the milk character was abnormal. Samples with Sc. dysgalactiae, Sc. agalactiae, or Sc. canis were included and a subset of isolates were further tested for in vitro antimicrobial resistance by breakpoint analysis with broth microdilution. Sc. dysgalactiae (61%, n = 65,750) was the most abundant pathogen among those 3 species, followed by Sc. agalactiae (28%, n = 30,486), and Sc. canis (11%, n = 11,336). All 3 species showed the highest resistance to the same 4 antimicrobial agents: erythromycin, marbofloxacin, pirlimycin, and cefalexin/kanamycin with varying degrees of resistance. Throughout the study period, Sc. dysgalactiae, Sc. agalactiae, and Sc. canis were largely susceptible to the remaining antimicrobial agents tested (penicillin, amoxicillin-clavulanate, oxacillin, cefazolin, cefoperazone, cefquinome). Only less than 14% of isolates of Sc. dysgalactiae and Sc. canis were resistant against any of the antimicrobials tested. Sc. agalactiae was the species with the highest percentage of resistant isolates. While the percentage of resistant isolates from Sc. canis and Sc. dysgalactiae decreased, the percentage of resistant Sc. agalactiae isolates increased since 2017. In summary, most isolates were not resistant to the most commonly used antimicrobial agents for mastitis therapy, including ß-lactam antibiotics and penicillin should remain the first-choice therapy against streptococcal mastitis.

RESUMEN

Solid core photonic crystal fibers (SC-PCFs) have garnered attention as probes for surface-enhanced Raman spectroscopy (SERS) due to their potential as optofluidic devices, offering heightened sensitivity and reliability compared to traditional planar/colloidal nanoparticle-based SERS platforms. A smaller core allows for more light interaction but might compromise sensitivity and reliability due to reduced surface area for interaction. Here, we introduce an innovative SC-PCF design aimed at resolving the trade-off between increasing the evanescent field fraction and the core surface area. By substituting a suspended silica rod with a suspended thin-silica ring, we augment the surface area for attached nanoparticles by one order of magnitude while retaining a substantial amount of evanescent light interaction with the analyte. Experimental findings showcase an improved sensitivity in SERS signal compared to previously reported top-performing PCF sensor designs. Importantly, with necessary refinement and optimization, this innovative fiber design extends beyond SERS applications, potentially amplifying the sensitivity of various other fiber-based sensing platforms.