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1.
Artigo em Inglês | MEDLINE | ID: mdl-38961556

RESUMO

INTRODUCTION: Intrauterine insemination (IUI) is one of the most widespread fertility treatments. However, IUI protocols vary significantly amongst fertility clinics. Various add-on interventions have been proposed to boost success rates. These are mostly chosen arbitrarily or empirically. The aim of this systematic review and meta-analysis is to assess the effectiveness and safety of add-on interventions to the standard IUI protocol and to provide evidence-based recommendations on techniques used to optimize the clinical outcomes of IUI treatment. MATERIAL AND METHODS: Systematic review and meta-analyses were performed in accordance with PRISMA guidelines. A computerized literature search was performed from database inception to May 2023. Randomized controlled trials (RCTs) were included reporting on couples/single women undergoing IUI with any protocol for any indication using partner's or donor sperm. A meta-analysis based on random effects was performed for each outcome and add-on. Three authors independently assessed the trials for quality and risk of bias and overall certainty of evidence. Uncertainties were resolved through consensus. Primary outcomes were ongoing pregnancy rate (OPR) or live birth rate (LBR) per cycle/per woman randomized. Registration number PROSPERO: CRD42022300857. RESULTS: Sixty-six RCTs were included in the analysis (16 305 participants across 20 countries). Vaginal progesterone as luteal phase support in stimulated cycles was found to significantly increase LBR/OPR (RR 1.37, 95% CI 1.09-1.72, I2 = 4.9%) (moderate/low certainty of the evidence). Endometrial scratch prior/during stimulated IUI cycles may increase LBR/OPR (RR 1.44, 95% CI 1.03-2.01, I2 = 1.8%), but evidence is very uncertain. Results from two studies suggest that follicular phase ovarian stimulation increases LBR/OPR (RR 1.39, 95% CI 1.00-1.94, I2 = 0%) (low certainty of evidence). No significant difference was seen for the primary outcome for the other studied interventions. CONCLUSIONS: The findings of this systematic review and meta-analysis suggest that vaginal luteal phase progesterone support probably improves LBR/OPR in stimulated IUI treatments. In view of moderate/low certainty of the evidence more research is needed for solid conclusions. Further research is also recommended for the use of endometrial scratch and ovarian stimulation. Future studies should report on results according to subfertility background as it is possible that different add-ons could benefit specific patient groups.

2.
J Biophotonics ; : e202400033, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38962832

RESUMO

Different approaches on wound healing have been developed over the years but they suffer from high costs and adverse effects for the patients. The current paper was designed to study low dose PDT, a novel healing approach, in an in vitro fibroblasts wound healing model. Chloroaluminum phthalocyanine (AlClPc) was used as photosensitizer and was activated by a red diode laser at 661 nm. After PDT optimization, wound closure rate and reactive oxygen species were quantified by image processing and analysis. Our results revealed that wound healing rates were significantly higher in PDT treated groups than in the control. Additionally, the study revealed that a prolonged ROS increase did not promote wound closure, while a small increase acted as a trigger, resulting in faster wound closure. Concluding, low dose PDT using AlClPc enhances wound healing in vitro in a ROS dependent manner, allowing the assumption of similar positive effects in vivo.

3.
Future Microbiol ; : 1-6, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39016073

RESUMO

We report a case of Vandammella animalimorsus in an adult female patient following a cat scratch/bite. Animal bite/scratches may lead to zoonotic transmission of bacteria that subsequently lead to infection. Wound management and antimicrobial therapy is often necessary. The organism was initially misidentified as Neisseria animaloris/zoodegmatis and highlights the difficulty of correctly identifying some bacteria in clinical microbiology laboratories.


Dogs and cats carry bacteria that are not carried in humans. Dog and cat bites or scratches may lead to these bacteria being spread to humans. This can lead to infection. These infections are usually treated by wound care and antibiotics. We describe a case of infection in a human with a bacteria from a cat following a cat bite/scratch to the patient's leg and discuss how the infection was diagnosed and treated.

4.
ACS Appl Mater Interfaces ; 16(28): 37234-37247, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38967116

RESUMO

Monocrystalline barium fluoride (BaF2), known for its exceptional optical properties in the infrared spectrum, exhibits anisotropy that influences surface quality and material removal efficiency during ultraprecision machining. This research explores the impact of anisotropy on the deformation and removal mechanisms of monocrystalline BaF2 by integrating nanoscratch tests with molecular dynamics (MD) simulations. Nanoscratch tests conducted on variously oriented monocrystalline BaF2 surfaces using a ramp loading mode facilitated the identification of surface cracks and a systematic description of material removal behaviors. This study elucidates the effect of crystal orientation on the ductile-brittle transition (DBT) of monocrystalline BaF2, further developing a critical depth prediction model for DBT on the (111) crystal plane to reveal the underlying anisotropy mechanisms. Moreover, nanofriction and wear behaviors in monocrystalline BaF2 are found to be predominantly influenced by scratch direction, crystal surface, and applied load, with the (110) and (100) planes showing pronounced frictional and wear anisotropy. A coefficient of friction model, accounting for the material's elastic recovery, establishes the intrinsic relationship between anisotropic friction and wear behaviors, the size effect, and scratch direction. Lastly, MD modeling of nanoscratched monocrystalline BaF2 reveals the diversity of dislocations and strain distributions along the (111) [-110] and [-1-12] crystal directions, offering atomic scale insights into the origins of BaF2 anisotropy. Thus, this study provides a theoretical foundation for the efficient processing of fluorine-based infrared optic materials exhibiting anisotropy.

5.
Hu Li Za Zhi ; 71(4): 6-11, 2024 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-39084887

RESUMO

Game-based teaching strategies enrich nursing education by enhancing the appeal and practicality of teaching activities. Different from the high-pressure and serious nature of traditional nursing education, interactive and entertaining teaching strategies that employ board games, card games, escape rooms, virtual reality, scratch cards, Kahoot quiz competitions, and other innovative methods better motivate learners to engage actively with learning content and retain nursing knowledge and practices, resulting in better learning outcomes. Game-based teaching strategies not only strengthen learners' mastery of core nursing concepts but also enhance their decision-making and critical-thinking abilities. In this article, practical applications of game-based teaching are introduced, in hopes that, by applying these instructional approaches, educators can alleviate the stress of the learning process and make learning more efficient and enjoyable for students.


Assuntos
Competência Clínica , Educação em Enfermagem , Humanos , Educação em Enfermagem/métodos , Aprendizagem
6.
Radiol Case Rep ; 19(9): 3770-3775, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38983285

RESUMO

Cat scratch disease is a rare condition that can present with different clinical manifestations, including axillary lymphadenopathy. Here, we report the case of a 45-year-old female who presented with axillary lymphadenopathy attributable to a process of differential diagnosis to cat scratch disease. During the thorough investigation of her condition, a routine mammogram was performed, due to the unilateral axillary lymphadenopathy, revealing the presence of previously undiagnosed breast carcinoma in situ; in fact, a DCIS (invasive ductal carcinoma with spread to the ipsilateral axillary nodes) was incidentally found. This case highlights the importance of comprehensive differential diagnosis and a multidisciplinary approach in managing patients with atypical presentations of common diseases, given that other alarming but unrelated findings are visible.

7.
J Dermatol ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38995202
8.
Pharmaceutics ; 16(7)2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-39065550

RESUMO

With increasing longevity globally, the search for effective and patient-friendly anti-aging solutions has been growing. Retinoic acid (Ret) is an FDA-approved anti-aging and anti-wrinkling formula, however, its poor solubility and poor tolerability hamper its use in cosmetically accepted formulations. In this study, cyclodextrins and arginine were investigated for improving the solubility and tolerability of retinoic acid through the formation of inclusion complexes and salt formation, respectively. Two different methods were employed: physical mixing and kneading. The prepared dispersions were investigated for molecular docking (MD), solubility, thermal and spectral analyses, cytotoxicity, and scratch assays. The optimized disperse systems were formulated in a gel formulation and characterized for rheological, in vitro release, and kinetics. The MD, DSC, and FTIR results indicated that both ß- and hydroxy propyl (HP) ß-cyclodextrins could host RA in their cavities and form inclusion complexes. Ret can form a salt with the basic amino acid arginine. Solubility studies of RA significantly (p < 0.01) enhanced by 14- to 81-fold increases with the investigated cyclodextrins and arginine. The cell viability recorded for Ret:HP ß-CD K and Ret:arginine K was significantly increased compared to that for Ret alone. The IC50% recorded for azelaic acid (mild to non-irritant control), Ret, Ret:HP ß-CD K, and Ret:arginine K were 1000, 485, 1100, and 895 µg/mL, respectively. The two carriers (HP ß-CD and the amino acid arginine) were able to significantly (p < 0.05) reduce the irritation potential of Ret. Furthermore, comparable gap closure rates were recorded for Ret alone, Ret:HP ß-CD K, and Ret:arginine K, indicating that inclusion complexation and ion pair formation reduced the irritation potentials without undermining the efficacy.

9.
J Ethnopharmacol ; : 118632, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39069028

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Lobostemon fruticosus (L.) H.Buek is a perennial and woody shrub of the Boraginaceae family, found in the Cape region of South Africa. The leaves and twigs are used to treat dermatological conditions such as wounds, burns, ringworm, erysipelas and eczema. Anti-inflammatory, antibacterial, antiviral and anti-proliferative activities of L. fruticosus have been reported. However, there is a void in research which reports on the wound healing properties of this plant. AIM OF THE STUDY: Aligned with the traditional use of L. fruticosus, our study aimed to use in vitro and in vivo bioassays to confirm the wound healing potential of the plant. MATERIALS AND METHODS: An aqueous methanol extract (80% v/v) of L. fruticosus was prepared using a sample collected from the Western Cape Province of South Africa and chromatographically profiled by ultra-performance liquid chromatography coupled to mass spectrometry (UPLC-MS). The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cytotoxicity assay was performed to screen the non-toxic concentrations of the extract for subsequent use in the in vitro scratch assay. Both the human keratinocyte (HaCaT) and fibroblast (BJ-5ta) cell lines were employed in the in vitro scratch assay. The in vivo caudal fin amputation assay was used to assess the wound healing potential of L. fruticosus, by monitoring fin regeneration in zebrafish larvae treated with the plant extract at various concentrations. RESULTS: Six major compounds were tentatively identified in the L. fruticosus extract namely; globoidnan A, globoidnan B, rutin, rabdosiin, sagerinic acid and rosmarinic acid. The potentially toxic pyrrolizidine alkaloids were also identified and quantitatively confirmed to be present at a low concentration of 119.58 ppm (m/m). Treatment of HaCaT and BJ-5ta cells with the plant extract in the scratch assay resulted in an increase in cell migration, which translates to accelerated wound closure. After 24 hr treatment with 100 µg/mL of extract, wound closure was recorded to be 91.1±5.7% and 94.1±1.3% for the HaCaT and BJ-5ta cells, respectively, while the untreated (medium) controls showed 72.3±3.3% and 73.0±4.3% for the two cell lines, respectively. Complete wound closure was observed between 24 and 36 hr, while the untreated control group did not achieve 100% wound closure by the end of the observation period (48 hr). In vivo, the crude extract at 100 µg/mL accelerated zebrafish caudal fin regeneration achieving 100.5±3.8% regeneration compared to 68.3±6.6% in the untreated control at two days post amputation. CONCLUSIONS: The study affirms the wound healing properties, as well as low toxicity of L. fruticosus using both in vitro and in vivo assays, which supports the traditional medicinal use. Other in vitro assays that target different mechanisms involved in wound healing should be investigated to support the current findings.

10.
J Ultrasound ; 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38907790

RESUMO

Cat-scratch disease is a well-known infection in childhood. It usually presents as tender lymphadenopathy and should be included in the differential diagnosis of any lymphadenopathy syndrome. An history of exposure to cats supports the suspect and a positive serologic test to Bartonella henselae confirms the diagnosis. Ultrasound is the first line radiologic imaging performed in case of lymphadenopathy. The presence of hypoechoic lobular or oval mass with central hyperaemia and a possible adjacent fluid collection and surrounding oedema may differentiate the disease from other aetiologies. We describe the case of a 7-year-old girl presenting with an axillary lymphadenopathy, without a reported recent history of exposure to cats, with sonographic findings suggestive for cat-scratch disease. In this case, ultrasound was very useful in orienteering the diagnosis and insist on the medical history. Serology resulted positive for B. henselae and at the end the family remembered that 6 months before the child was scratched by a kitten.

11.
Medicina (B Aires) ; 84(3): 474-480, 2024.
Artigo em Espanhol | MEDLINE | ID: mdl-38907961

RESUMO

INTRODUCTION: Cat-scratch disease (CSD) is caused by Bartonella henselae and it is under-recognized in adults because it mainly affects children. Clinical course is commonly benign and self-limited; occasionally, there may be systemic involvement. METHODS: Case-series study carried out in a tertiary care hospital in Buenos Aires suburbs. Patients older than 15 years diagnosed with CSD over a 5-year period were included (2016-2021). RESULTS: 30 adult patients were analyzed, with a median age of 20.5 years (IQR 17-29), 73% (n = 22) were male; 96% (n = 27) had history of exposure to cats. The most common clinical presentation of CSD was peripheral lymphadenopathy (90%), the average complication rate was 33% (n = 10), 86.7% (n = 26) received antimicrobial therapy, with a median duration of 5 days (IQR 5-10). Outcome was favorable in 83% (n = 25), 16% (n = 5) were lost to follow-up. DISCUSSION: Clinical features of CSD in adults are poorly described in the worldwide literature. Diagnosis can be challenging because the clinical hallmark is regional lymphadenopathy.


Introducción: La enfermedad por arañazo de gato (EAG) es producida por Bartonella henselae y debido a que afecta principalmente niños, es poco reconocida en adultos. El cuadro evolutivo es generalmente benigno y autolimitado, aunque ocasionalmente puede haber compromiso sistémico. Métodos: Estudio observacional, descriptivo y retrospectivo realizado en un hospital de tercer nivel del conurbano bonaerense. Se incluyeron pacientes mayores de 15 años con diagnóstico de EAG en un período de 5 años (2016-2021). Resultados: Se analizaron 30 pacientes adultos, con una mediana de edad de 20.5 años (17-29), el 73% (n = 22) fueron varones. El 96% (n = 27) presentó contacto estrecho con gatos. La presentación clínica más frecuente fue adenopatías periféricas (90%); el porcentaje de complicaciones fue de 33% (n = 10). La indicación de antibioticoterapia fue de 86.7% (n = 26), con una mediana de duración de 5 días (5-10). La evolución fue favorable en el 83% (n = 25), en el 16% (n = 5) se perdió seguimiento. Discusión: La EAG es poco reconocida en adultos; las características clínicas de este grupo etario se encuentran poco descriptas en la literatura. Es un desafío diagnóstico debido a que su forma de presentación más frecuente es la adenopatía localizada.


Assuntos
Bartonella henselae , Doença da Arranhadura de Gato , Humanos , Doença da Arranhadura de Gato/diagnóstico , Doença da Arranhadura de Gato/tratamento farmacológico , Masculino , Adulto , Feminino , Adulto Jovem , Adolescente , Bartonella henselae/isolamento & purificação , Antibacterianos/uso terapêutico , Linfadenopatia , Estudos Retrospectivos , Argentina , Animais , Gatos
12.
Regen Ther ; 26: 170-179, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38911026

RESUMO

With over 9 million fatalities per year expected by 2030, infectious diseases will remain a significant burden on the world economy and cause high mortality rates. An excellent method to increase the bioactivity of levofloxacin (LEV) in pediatric abdominal wound repair is the finding of a stimuli-based drug delivery system (DDS). We designed and developed an LEV incorporated with zeolite imidazole framework-8 (ZIF-8) as a promising nanocarrier for wound healing applications. The spectral analysis and morphological analysis confirm the formation of our newly fabricated composites. Mouse embryonic fibroblast NIH3T3 cells, the cytotoxicity, cytocompatibility, and cell proliferation characteristics of LEV@ZIF-8 were evaluated in vitro. LEV@ZIF-8 composite considerably improved the biocompatibility against NIH3T3 cells after 72-h of exposure, according to in vitro experiments. Under acidic circumstances, the pH-responsive drug release studies exhibit superior LEV release, and in physiological circumstances, there is no unintended drug release. The LEV@ZIF-8 composite-treated cells demonstrate the most remarkable cell growth and migration method in a very short time, according to the results of the wound scratch experiment. The composite exposure concentration depended on inhibition against various microorganisms in the antibacterial activity testing. According to the study, LEV@ZIF-8 are appropriate and effective DDS for stimuli-based pediatric abdominal wound repair.

13.
Biol Reprod ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38910516

RESUMO

In cattle, the endometrium during diestrus and early pregnancy displays cellular responses that are consequences of prior, transient stimuli. Goal was to establish a model to study cellular memory in the endometrium. The hypothesis is that stimuli given to endometrium in vivo are retained as a cellular memory that remains after bovine uterine epithelial cells (BUECs) are isolated, cultured, and further stimulated in vitro. Objectives were to measure BUEC proliferation/migration and responsiveness to recombinant bovine Interferon-tau (rbIFNT) in vitro: among cows that showed estrus (experiment 1 [Exp1]), cows that became or not pregnant to artificial insemination (Exp2), cows that received or not supplemental progesterone (P4; Exp3) and cows that received or not a COX-1/2 inhibitor (Exp4). Only cows that displayed estrus were included in studies. For all experiments endometrial cytology was collected 4 days after estrus, BUECs were cultured, propagated, and submitted to rbIFNT treatment and an in vitro scratch assay. In Exp1, different cows spontaneously grouped according to proliferative/migratory capacity and responsiveness to rbIFNT of their respective BUECs. In Exp2, BUECs from pregnant cows showed greater rbIFNT responsiveness and cellular proliferation. In Exp3, BUECs from cows supplemented with P4 presented inhibited proliferation and increased expression of RSAD2. In Exp4, Flunixin Meglumine modified rbIFNT responsiveness of BUECs in an IFN-signaling pathway-specific manner. In conclusion, physiological and pharmacological stimuli received by the endometrium in vivo were retained as cellular memory in BUECs, persisted in culture, and changed BUEC proliferation/migration and responsiveness to rbIFNT, which are characteristics associated with fertility in cattle.

14.
J Pharm Sci ; 2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38862089

RESUMO

Drug repurposing is a potential strategy to overcome the huge economic expenses of wound healing products. This work aims to develop a topical gel of piroxicam encapsulated into a nanospanlastics vesicular system as an effective, dermal wound dressing. Firstly, piroxicam was entrapped into nanospanlastics formulations and optimized utilizing 23 full factorial experimental designs. The scrutinized factors were Span 60: Edge activator ratio, edge activator type, and permeation enhancer type. The measured responses were vesicle size (VS), polydispersity index (PDI), and% entrapment efficiency (EE). The optimized formula was further adopted into an alginate-pectin gel matrix to maximize adherence to the skin. The rheology and in-vitro release were studied for the developed nanospanlastics gel. Cytotoxicity and wound healing potential using scratch assay were assessed on human adult dermal fibroblast cells. The optimal piroxicam nanospanlastics formula demonstrated a VS of 124.1 ± 1.3 nm, PDI of 0.21 ± 0.01, and EE% of 97.27±0.21%. About 70.0 ± 0.9% and 57.4 ± 0.1% of piroxicam were released from nanospanlastics dispersion and gel within 24 h, respectively. Nanospanlastics gel of piroxicam flowed in a non-Newtonian pseudoplastic shear thinning pattern. It was also biocompatible with the human dermal fibroblast cells and significantly promoted their migration rate which suggests an auspicious cutaneous wound healing aptitude.

15.
Nat Prod Res ; : 1-5, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38885341

RESUMO

Skin lesions are considered a public health problem, compromising patients' quality of life. This work aimed to evaluate the effects of fraxetin and monnieriside A on Cultured L929 Fibroblasts through the scratch assay. Supernatants and cells from the fibroblast culture treated with the compounds were used to evaluate essential markers of the tissue repair process (IGF-1, VEGF, IL-8, IL-10, FGF-2, COL1A2, COL4A, PDGF) using ELISA and qRT-PCR. The results showed that fraxetin and MOA were non-cytotoxic and could stimulate cellular migration. Fraxetin induced IGF-1, VEGF, IL-8, and IL-10 expression, while MOA induced FGF2, COL1A2, and IL-10 expression. Altogether, these results set provides evidence that fraxetin and MOA have healing potential for tissue repair, paving the way for in vivo studies and clinical trials to validate the in vitro results.

16.
Sensors (Basel) ; 24(11)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38894155

RESUMO

Nocturnal scratching substantially impairs the quality of life in individuals with skin conditions such as atopic dermatitis (AD). Current clinical measurements of scratch rely on patient-reported outcomes (PROs) on itch over the last 24 h. Such measurements lack objectivity and sensitivity. Digital health technologies (DHTs), such as wearable sensors, have been widely used to capture behaviors in clinical and real-world settings. In this work, we develop and validate a machine learning algorithm using wrist-wearing actigraphy that could objectively quantify nocturnal scratching events, therefore facilitating accurate assessment of disease progression, treatment effectiveness, and overall quality of life in AD patients. A total of seven subjects were enrolled in a study to generate data overnight in an inpatient setting. Several machine learning models were developed, and their performance was compared. Results demonstrated that the best-performing model achieved the F1 score of 0.45 on the test set, accompanied by a precision of 0.44 and a recall of 0.46. Upon satisfactory performance with an expanded subject pool, our automatic scratch detection algorithm holds the potential for objectively assessing sleep quality and disease state in AD patients. This advancement promises to inform and refine therapeutic strategies for individuals with AD.


Assuntos
Actigrafia , Algoritmos , Dermatite Atópica , Aprendizado de Máquina , Prurido , Punho , Humanos , Actigrafia/métodos , Actigrafia/instrumentação , Punho/fisiologia , Masculino , Feminino , Adulto , Prurido/fisiopatologia , Prurido/diagnóstico , Dispositivos Eletrônicos Vestíveis , Qualidade de Vida , Sono/fisiologia , Pessoa de Meia-Idade
17.
Cureus ; 16(5): e60609, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38894778

RESUMO

Cat-scratch disease (CSD), a human infection resulting from Bartonella species, commonly manifests as tender lymphadenopathy. Consequently, its inclusion in the differential diagnosis of fevers of unknown origin and lymphadenopathy syndromes is imperative. Typically, it manifests as self-limiting tender lymphadenopathy and does not lead to fatalities, though it may assume a more severe course in immunocompromised individuals. Diagnostic challenges often surround CSD due to its elusive nature in laboratory tests, necessitating a reliance on the clinical presentation for definitive diagnosis. This can manifest in delayed procedures and testing, which can prolong intervention and cause rapid progress of bacteria, potentially causing severe complications and death. In this case report of a 58-year-old Caucasian male, we delve into the clinical presentation and eventual fatality of CSD in a patient with liver cirrhosis, occurring in the United States. He sought care in the emergency department due to lethargy, fever, and swollen axilla following a cat scratch. Although the patient did not exhibit signs of sepsis upon admission, he rapidly progressed to sepsis and passed away within 24 hours. This case highlights the significance of timely and proactive management in individuals presenting with CSD, especially when complicated by underlying immunocompromised conditions. Early recognition, the administration of suitable antibiotics, and comprehensive supportive care are pivotal in averting fatal outcomes in such cases.

18.
J Dent Res ; : 220345241256279, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38877734

RESUMO

Computer-aided design (CAD)/computer-aided manufacturing (CAM) milling and handpiece grinding are critical procedures in the fabrication and adjustment of ceramic dental restorations. However, due to the formation of microfractures, these procedures are detrimental to the strength of ceramics. This study analyzes the damage associated with current brittle-regime grinding and presents a potential remedy in the application of a safer yet still efficient grinding regime known as "ductile-regime grinding." Disc-shaped specimens of a lithium disilicate glass-ceramic material (IPS e.max CAD) were obtained by cutting and crystallizing the lithium metasilicate CAD/CAM blanks (the so-called blue blocks) following the manufacturer's instructions. The discs were then polished to a 1 µm diamond suspension finish. Single-particle micro-scratch tests (n = 10) with a conical diamond indenter were conducted to reproduce basic modes of deformation and fracture. Key parameters such as coefficient of friction and penetration depth were recorded as a function of scratch load. Further, biaxial flexure strength tests (n = 6) were performed after applying various scratch loads to analyze their effects on ceramic strength. Scanning electron microscopy (SEM) and focused ion beam (FIB) were used to characterize surface and subsurface damage. Statistical analysis was performed using one-way analysis of variance and Tukey tests. While the SEM surface analysis of scratch tracks revealed the occurrence of both ductile and brittle removal modes, it failed to accurately determine the threshold load for the brittle-ductile transition. The threshold load for brittle-ductile transition was determined to be 70 mN based on FIB subsurface damage analyses in conjunction with strength degradation studies. Below 70 mN, the specimens exhibited neither strength degradation nor the formation of subsurface cracks. Determination of the brittle-ductile thresholds is significant because it sets a foundation for future research on the feasibility of implementing ductile-regime milling/grinding protocols for fabricating damage-free ceramic dental restorations.

19.
Eur J Clin Microbiol Infect Dis ; 43(8): 1661-1665, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38913229

RESUMO

Cat scratch disease (CSD) is an infection caused by Bartonella henselae, presents with non-specific symptoms like lymphadenopathy, fever, and fatigue. It can progress to disseminated disease, leading to complications such as liver and splenic micro abscesses, osteomyelitis, encephalitis, and uveitis. Diagnosis is challenging due to varied presentations and limited tests. Treatment involves supportive care, with severe cases requiring antimicrobial therapy. In this report, we present a case of Cat scratch disease characterized by an atypical clinical manifestation, hepatosplenic and paravertebral involvement.


Assuntos
Bartonella henselae , Doença da Arranhadura de Gato , Doença da Arranhadura de Gato/diagnóstico , Doença da Arranhadura de Gato/tratamento farmacológico , Doença da Arranhadura de Gato/microbiologia , Humanos , Bartonella henselae/isolamento & purificação , Masculino , Antibacterianos/uso terapêutico , Feminino , Adulto
20.
Materials (Basel) ; 17(12)2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38930186

RESUMO

Ultra-thin 304 stainless steel can be used to flexibly display substrates after they have been subjected to chemical mechanical polishing (CMP). The thickness of the chemical oxide layer directly affects the polishing efficiency and surface quality of 304 stainless steel. In the study presented in the following paper, the thickness variation of the chemical oxide layer of 304 stainless steel was analyzed following electrochemical corrosion under different oxidant concentration conditions. Furthermore, the impact of the oxidant concentration on the grooves, chips, and scratch depth-displacement-load curves was investigated during a nano-scratching experiment. Through this process, we were able to reveal the chemical reaction mechanism between 304 stainless steel materials and oxidizers. The corrosion rate was found to be faster at 8% oxidant content. The maximum values of the scratch depth and elastic-plastic critical load were determined to be 2153 nm and 58.47 mN, respectively.

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