Search Results (15)

Pulmonary cryptococcosis is an invasive fungal infection usually linked to severe immunosuppression, particularly HIV/AIDS, but is increasingly reported in immunocompetent hosts, including those with uncontrolled diabetes mellitus (DM). We describe a 51-year-old woman with poorly controlled type 2 DM and no other immunosuppressive conditions who developed pulmonary cryptococcosis. Diagnosis was made by microscopy, India ink, cryptococcal antigen lateral flow assay (CrAg LFA), and ITS sequencing; culture was negative. Despite treatment with deoxycholate amphotericin B and fluconazole, the patient died 36 days after admission. A systematic literature review (2000–2025) identified 40 cases of pulmonary cryptococcosis, with 17.5% occurring in patients whose only comorbidity was DM. Cryptococcus neoformans was the most frequent species. Non-culture-based methods, especially CrAg detection, were widely used, underscoring their value for rapid and sensitive diagnosis. Pulmonary cryptococcosis should be considered in diabetic patients even without classical immunosuppression. Broader use of non-culture-based diagnostic tools may enable earlier intervention, which is particularly relevant in resource-limited settings such as Honduras. Full article

A polyamidoamine-based hydrogel (H-M-GLY) and its montmorillonite-based composite (H-M-GLY/MMT) were studied as selective cleaning materials for cultural heritage conservation. H-M-GLY was synthesized from a glycine-based polyamidoamine oligomer with acrylamide terminals (M-GLY) through radical polymerization at pH 7.3 and had a basic character. The M-GLY oligomer was in turn synthesized from N,N′-methylenebisacrylamide and glycine in a 1:0.85 molar ratio. H-M-GLY/MMT was obtained by cross-linking a 1:0.1—weight ratio—M-GLY/MMT mixture at pH 4.0, to promote polyamidoamine-MMT interaction. The composite hydrogel absorbed less water than the plain hydrogel and proved tougher, due to montmorillonite’s electrostatic interactions with the positively charged M-GLY units. Scanning electron microscopic analysis showed that MMT was uniformly dispersed throughout the hydrogel. Both hydrogels were subjected to ink bleeding tests on papers written with either iron gall or India ink. Microscopic observation revealed neither bleeding nor release of hydrogel fragments. Being basic, H-M-GLY successfully deacidified the surface of aged paper. H-M-GLY/MMT, swollen in a 1:9 ethanol/water solution, was found to be effective in removing wax, known to trap carbonaceous particles and form dark stains on artistic artifacts. This study demonstrates the great potential of polyamidoamine-based hydrogels as versatile selective cleaning systems for cellulosic and other cultural heritage materials. Full article

This study describes the design and validation of an experimental setup for testing photoplethysmographic (PPG) devices intended for the non-invasive monitoring of vascular accesses in hemodialysis patients. Continuous assessment of arteriovenous fistulas is essential to detect pathological conditions such as stenosis, which can compromise patient safety and dialysis efficacy. While PPG-based sensors are capable of detecting such anomalies, their clinical applicability must be supported by controlled in vitro validation. The developed system replicates the anatomical, mechanical, optical, and hemodynamic features of vascular accesses. A 3D fistula model was designed and fabricated via 3D printing and silicone casting. The hydraulic circuit used red India ink and a PWM-controlled pump to simulate physiological blood flow, including stenotic conditions. Quantitative validation confirmed anatomical accuracy within 0.1 mm tolerance. The phantom exhibited an average Shore A hardness of 20.3 ± 1.1, a Young’s modulus of 10.4 ± 0.9 MPa, and a compression modulus of 105 MPa—values consistent with soft tissue behavior. Burst pressure exceeded 2000 mmHg, meeting ISO 7198:2016 standards. Flow rates (400–700 mL/min) showed <1% error. Compliance was 2.4 ± 0.2, and simulated blood viscosity was 3.9 ± 0.3 mPa·s. Systolic and diastolic pressures fell within physiological ranges. Photoplethysmographic signals acquired using a MAX30102 sensor (Analog devices Inc., Wilmington, MA, USA) reproduced key components of in vivo waveforms, confirming the system’s suitability for device testing. Full article

Cryptococcus neoformans (C. neoformans) is a capsulated yeast that enters the body through inhalation and migrates via the bloodstream to the central nervous system, causing cryptococcal meningitis. Diagnosis methods are culture, serology, and India ink staining, which require cerebrospinal fluid (CSF) or whole blood. Molecular methods are used for epidemiological studies and require expensive commercial DNA extraction kits. This study aimed to develop an economical in-house method for extracting C. neoformans DNA from whole blood. C. neoformans cells of varying McFarland standards were spiked into expired blood, then lysed using laboratory-prepared lysis buffer and ox-bile solution, followed by organic DNA extraction. Ordinary PCR targeting the CNAG 04922 gene was performed. To determine the limit of detection, serial dilutions of C. neoformans were made, and DNA extraction was performed on other parts cultured on yeast extract peptone dextrose agar to determine colony-forming units (CFU). The lysis buffer method successfully extracted DNA from as low as the average of 62 CFU in 0.9 mL of expired blood with superior quality and high yield compared to ox-bile. The lysis buffer method yielded higher DNA quality and quantity than ox-bile and detected low concentrations of C. neoformans in expired blood. This method presents a cost-effective alternative for molecular diagnosis in resource-limited settings. Full article

Herbert D. Athearn (1923–2011) was an avid student of freshwater mollusks. He named his private shell collection “The Museum of Fluviatile Mollusks”, which was meticulously organized at his residence. This collection was curated to current museum standards with detailed labels, all lots with catalog numbers, and all unionoid valves with catalog numbers written in India ink. Specimens’ collecting dates span between 1850 and 2005, with 23,344 cataloged lots containing over 3000 lots of imperiled and extinct taxa. All data for each of the lots are handwritten in paper catalogs. Many lots contain growth series from the smallest juveniles to the largest specimens seen. He traded extensively with collectors worldwide, obtaining specimens from 84 countries. This collection was donated to the North Carolina Museum of Natural Sciences in 2007. To date, 64 percent of this collection has been databased using a relational database, totaling 589,995 specimens. The collection consists of bivalves, primarily Unionidae, Margaritiferidae, and Sphaeriidae, as well as gastropods. There are 73 families represented, with the greatest abundance found in freshwater Pleuroceridae. The Athearn collection donation included his correspondence, his library, field notes, and USGS topographic maps with marked field localities. Full article

Intraluminal photoacoustic (PA) imaging has the potential for providing physiological and functional information in wide-ranging clinical applications. Along with endoluminal ultrasound transducers, these applications require compact light delivery devices which can deliver high-energy ns-pulsed laser to the target region. In this work, we describe the design, method of fabrication and characterization of a new compact, side-fire optical fiber that can deliver high-energy laser pulses for PA imaging. Side-fire illuminators were fabricated using UV laser ablation to create windows on the side of a 1.5 mm diameter single core, multi-mode optical fiber with a reflective silver coating and a beveled end. Devices with 10 mm, 20 mm, and 30 mm window lengths were fabricated and their beam profiles characterized. Elongated side-fire fibers with −6 dB beam size up to 30.79 mm × 5.5 mm were developed. A side-fire to total output ratio of up to 0.69 and a side fire efficiency of up to 40%, relative to a standard front-fire fiber, were achieved. We evaluated the effects of high-energy ns-pulsed light propagation on the fiber by coupling the fiber to 18 mJ or 100 MW/cm² (at 750 nm) beam from a Q-switched laser. The PA imaging with the fiber was demonstrated by detecting India ink targets embedded in chicken breast tissue over the full length of a 20 mm illumination window and over a 100° angle and by visualizing in vivo the rat ear vasculature. Full article

Cryptococcal meningoencephalitis is a systemic fungal infection in immunocompromised and immunocompetent individuals. This study investigated the clinical characteristics and factors associated with mortality in HIV-associated and non-HIV-associated cryptococcal meningoencephalitis in a resource-limited setting. This was a retrospective cohort study of patients with cryptococcal meningoencephalitis between January 2009 and December 2019 at a tertiary teaching hospital in Thailand. Overall, 1019 patients with cryptococcal meningoencephalitis were enrolled, and 923 (90.6%) were HIV-positive. The patients with HIV-associated cryptococcal meningoencephalitis were younger than the HIV-negative patients (37 versus 56 years, p < 0.01). The HIV-negative patients were more likely to have underlying conditions (52.1% versus 7.5%; p < 0.01), had a longer median duration of headaches prior to admission (14 days versus 6 days, p < 0.01), and were more likely to have an altered mental status at presentation (36.5% versus 18.6%, p < 0.01) and pulmonary involvement (15.6% versus 0.8%, p < 0.01). The HIV-positive patients had lower cerebrospinal fluid (CSF) white blood cell counts (4 versus 94 cells/mm³; p < 0.01), lower CSF protein (69 versus 157 mg/dL; p < 0.01), higher CSF glucose (38.8 versus 21 mg/dL; p < 0.01), and more frequent cryptococcemia (44.1% versus 20.5%; p < 0.01). The mortality rate was high but not significantly different between the two groups (30.2% versus 33.2%; p = 0.53). The HIV-positive patients with comorbidities, fever, an altered mental status at presentation, a CSF white blood cell count below 20 cell/mm³, fungemia, and positive CSF India ink were independently associated with 30-day mortality. In comparison, an altered mental status at presentation and fungemia were associated with 30-day mortality in HIV-negative patients. In conclusion, HIV-negative patients with cryptococcal meningoencephalitis had more extensive central nervous system inflammation, although the two groups’ mortality rates were similar. Unfavorable prognostic factors included comorbidities, fever, an altered mental status at presentation, a low CSF white blood cell count, fungemia, and positive CSF India ink. Full article

Cryptococcal meningitis is a serious infection of the central nervous system that is predominant in developing countries, caused by fungi of the genus Cryptococcus, and which affects immunosuppressed patients, especially those with HIV. Here, we aim to diagnose and characterize the clinical–epidemiological profile of cryptococcosis in patients admitted to two tertiary public hospitals in northeastern Brazil. The study is divided into three moments: (1) the isolation of fungus and diagnosis from biological samples collected between 2017 and 2019, (2) a description of the clinical and epidemiological characteristics of the patients, and (3) the experimental tests related to an in vitro susceptibility antifungal profile. The species were identified by MALDI-TOF/MS. Among the 100 patients evaluated, 24 (24.5%) were diagnosed with cryptococcosis based on positive culture. Clinical–epidemiological analysis showed a slightly higher prevalence in men between 30 and 39 years. When comparing the date of HIV diagnosis and the development of cryptococcosis, it was observed that 50% received the diagnosis of infection by cryptococcosis after or equal to a period of 12 months from being diagnosed with HIV; the other 50% received it within the first 30 days of the HIV diagnosis. Neurocryptococcosis was the most prevalent clinical form, and, at the time of hospital admission, the most common clinical signs were high fever (75%), intense headache (62.50%), and neck stiffness (33.33%). The cerebrospinal fluid showed 100% sensitivity and positivity for direct examination by India ink, and fungal culture. The mortality rate in this study was 46% (11/24), a lower rate than in the other literature. An antifungigram showed that 20 (83.33%) isolates were susceptible to amphotericin B and 15 (62.5%) to fluconazole. Mass spectrometry identified 100% of the isolates as Cryptococcus neoformans. In Brazil, this infection is not mandatory notifiable. Therefore, although there is little information on the subject, it is obsolete and does not express the reality of the facts, mainly in the northeast region, where this information is insufficient. The data obtained in this research contribute to the epidemiological knowledge of this mycosis in Brazil and will serve as a basis for future globally comparative epidemiological studies. Full article

While upper tract access through the insensate conduit following urinary diversion takes less time and incurs fewer costs than percutaneous kidney access does for the treatment of ureter and kidney pathology, endoscopic ureteroenteric anastomoses (UEA) identification can be difficult. We injected India Ink into the bowel mucosa near the UEA during ileal conduit diversion (IC) to determine the safety and feasibility of ink tattooing. Patients undergoing IC were prospectively randomized to receive ink or normal saline (NS) injections. The injections were placed 1 cm from UEA in a triangular configuration, and loopogram exams and looposcopy were performed to identify reflux (UR), UEA, the tattooing site and strictures in 10 and 11 patients randomized with respect to ink and NS injections, respectively. Ink patients were older (72 vs. 61 years old, p = 0.04) and had a higher Charlson Comorbidity Index (5 vs. 2, p = 0.01). Looposcopy was performed in three ink and four NS patients. Visualization of UEA was achieved in 100% of the ink and 75% of the NS patients (p = 0.26). The ink ureteroenteric anastomotic stricture (UEAS) rate was higher (N = 3 vs. N = 1) and six patients vs. one patients underwent surgery, respectively, for UEAS (p = 0.31). The study was halted early due to safety concerns. Our pilot study demonstrates that ink can be well visualized following injection near UEA during IC. However, the ink cohort had more UEAS than previously cited in the literature and our prior institutional UEAS rate of 6%. While this study sample is small, the higher incidence of UEAS after ink injection led us to question the utility and safety of ink injection following IC. Full article

Not many manuscript maps have been the object of material analysis so far. A portolan chart, signed and dated by Juan Vespucci in 1520, was studied in this research, conserved at the Archivo General de Indias in Seville (Spain). It is made on parchment and depicts the coasts and islands of Europe and Africa. It is the oldest portolan chart made in Seville, being unusual in applying hand stamp for decorative figures. The map was analysed by different non-invasive techniques: infra-red and ultraviolet light, digital microscope and X-ray fluorescence (XRF). The main goals of this study were to identify the materials used, as well as to detect retouching or restoration work. Results showed that the entire parchment was first covered with a white layer made of lead white (Pb), calcite or gypsum (Ca). The principal pigments used were vermilion (Hg), yellow ochre (Fe), azurite (Cu) and a copper-based green pigment (Cu) and carbon black. The letters were probably written with an iron-gall ink (Fe, Cu). Very thin golden leaves were applied on a mixtion glue for gilded wind roses. Several retouches from the 19th/20th centuries were found using zinc and titanium whites and probably cobalt blue. Full article

Fungal infections commonly present with myriad symptoms that mimic other clinical entities, notable amongst which is tuberculosis. Besides histoplasmosis and chronic pulmonary aspergillosis, which can mimic TB, this review has identified several other fungal infections which also do. A total of 80 individual cases misdiagnosed as TB are highlighted: aspergillosis (n = 18, 22.5%), histoplasmosis (n = 16, 20%), blastomycosis (n = 14, 17.5%), cryptococcosis (n = 11, 13.8%), talaromycosis (n = 7, 8.8%), coccidioidomycosis (n = 5, 6.3%), mucormycosis (n = 4, 5%), sporotrichosis (n = 3, 3.8%), phaeohyphomycosis (n = 1, 1.3%) and chromoblastomycosis (n = 1, 1.3%). Case series from India and Pakistan reported over 100 cases of chronic and allergic bronchopulmonary aspergillosis had received anti-TB therapy before the correct diagnosis was made. Forty-five cases (56.3%) had favorable outcomes, and 25 (33.8%) died, outcome was unclear in the remainder. Seventeen (21.3%) cases were infected with human immunodeficiency virus (HIV). Diagnostic modalities were histopathology (n = 46, 57.5%), culture (n = 42, 52.5%), serology (n = 18, 22.5%), cytology (n = 2, 2.5%), gene sequencing (n = 5, 6.3%) and microscopy (n = 10, 12.5%) including Gram stain, India ink preparation, bone marrow smear and KOH mount. We conclude that the above fungal infections should always be considered or ruled out whenever a patient presents with symptoms suggestive of tuberculosis which is unconfirmed thereby reducing prolonged hospital stay and mortalities associated with a delayed or incorrect diagnosis of fungal infections. Full article

Localization of tumors during laparoscopic surgery is generally performed by locally injecting India ink into the submucosal layer of the gastrointestinal tract using endoscopy. However, the location of the tumor is obscured because of the black-stained surgical field and the blurring caused by India ink. To solve this problem, in this study, we developed a tissue-adhesive porphyrin with polycations consisting of quaternary ammonium salt groups. To evaluate the ability of tissue-adhesive porphyrin in vivo, low-molecular-weight hematoporphyrin and tissue-adhesive porphyrin were injected into the anterior wall of the exposed stomach in rats. Local injection of low-molecular-weight hematoporphyrin into the anterior wall of the stomach was not visible even after 1 day because of its rapid diffusion. In contrast, the red fluorescence of the tissue-adhesive porphyrin was visible even after 7 days due to the electrostatic interactions between the positively-charged moieties of the polycation in the tissue-adhesive porphyrin and the negatively-charged molecules in the tissue. In addition, intraperitoneal injection of tissue-adhesive porphyrin in rats did not cause adverse effects such as weight loss, hepatic or renal dysfunction, or organ adhesion in the abdominal cavity. These results indicate that tissue-adhesive porphyrin is a promising fluorescent tissue-marking agent. Full article

This work presents the design and validation of an instrument for dual-slope broadband diffuse reflectance spectroscopy. This instrument affords calibration-free, continuous-wave measurements of broadband absorbance of optically diffusive media, which may be translated into absolute absorption spectra by adding frequency-domain measurements of scattering at two wavelengths. An experiment on a strongly scattering liquid phantom (milk, water, dyes) confirms the instrument’s ability to correctly identify spectral features and measure absolute absorption. This is done by sequentially adding three dyes, each featuring a distinct spectral absorption, to the milk/water phantom. After each dye addition, the absorption spectrum is measured, and it is found to reproduce the spectral features of the added dye. Additionally, the absorption spectrum is compared to the absorption values measured with a commercial frequency-domain instrument at two wavelengths. The measured absorption of the milk/water phantom quantitatively agrees with the known water absorption spectrum ($R^2=0.98$), and the measured absorption of the milk/water/dyes phantom quantitatively agrees with the absorption measured with the frequency-domain instrument in six of eight cases. Additionally, the measured absorption spectrum correctly recovers the concentration of one dye, black India ink, for which we could accurately determine the extinction spectrum (i.e., the specific absorption per unit concentration). The instrumental methods presented in this work can find applications in quantitative spectroscopy of optically diffusive media, and particularly in near-infrared spectroscopy of biological tissue. Full article

Currently there exists little knowledge or work in phantoms for the in-vitro evaluation of photoplethysmography (PPG), and its’ relationship with vascular mechanics. Such phantoms are needed to provide robust, basic scientific knowledge, which will underpin the current efforts in developing new PPG technologies for measuring or estimating blood pressure, blood flow and arterial stiffness, to name but a few. This work describes the design, fabrication and evaluation of finger tissue-simulating pulsatile phantoms with integrated custom vessels. A novel technique has been developed to produce custom polydimethylsiloxane (PDMS) vessels by a continuous dip-coating process. This process can accommodate the production of different sized vessel diameters (1400–2500 µm) and wall thicknesses (56–80 µm). These vessels were embedded into a mould with a solution of PDMS and India ink surrounding them. A pulsatile pump experimental rig was set up to test the phantoms, where flow rate (1–12 L·min⁻¹), heart rate (40–120 bpm), and total resistance (0–100% resistance clamps) could be controlled on demand. The resulting flow profiles approximates human blood flow, and the detected contact PPG signal (red and infrared) from the phantom closely resembles the morphology of in-vivo PPG waveforms with signal-to-noise ratios of 38.16 and 40.59 dB, for the red and infrared wavelengths, respectively. The progress made by this phantom development will help in obtaining new knowledge in the behaviour of PPG’s under differing flow conditions, optical tissue properties and differing vessel stiffness. Full article

Niemann–Pick type C (NPC) disease is a rare neurovisceral cholesterol storage disorder that arises from loss of function mutations in the NPC1 or NPC2 genes. Soon after birth, some patients present with an aggressive hepatosplenomegaly and cholestatic signs. Histopathologically, the liver presents with large numbers of foam cells; however, their role in disease pathogenesis has not been explored in depth. Here, we studied the consequences of gadolinium chloride (GdCl₃) treatment, a well-known Kupffer/foam cell inhibitor, at late stages of NPC liver disease and compared it with NPC1 genetic rescue in hepatocytes in vivo. GdCl₃ treatment successfully blocked the endocytic capacity of hepatic Kupffer/foam measured by India ink endocytosis, decreased the levels CD68—A marker of Kupffer cells in the liver—and normalized the transaminase levels in serum of NPC mice to a similar extent to those obtained by genetic Npc1 rescue of liver cells. Gadolinium salts are widely used as magnetic resonance imaging (MRI) contrasts. This study opens the possibility of targeting foam cells with gadolinium or by other means for improving NPC liver disease. Synopsis: Gadolinium chloride can effectively rescue some parameters of liver dysfunction in NPC mice and its potential use in patients should be carefully evaluated. Full article