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Objective: We developed a dual-diffusing optical fiber probe (DDOFP), capable of uniformly illuminating the anatomical structure of pancreatic duct for photodynamic therapy (PDT) of pancreatic cancer in clinical settings. Background: Optical fiber presents a unique route for pancreatic PDT by enabling access to the pancreatic duct. For effective pancreatic PDT, the optical fiber should produce a uniform illumination covering of the pancreatic duct, while maintaining its transmission property under thermomechanical stresses in surgical environments. Methods: The transmission profiles of DDOFP were measured using a charge-coupled device (CCD) camera at two directions: front-spherical and side-cylindrical areas of the optical fiber. We simulated the change in transmission property by curved tube structures using optically transparent phantom. DDOFP was integrated with 19-gauge needle catheter that is commercially used as an optical guide to treat pancreatic cancer. The temperature of DDOFP was measured at the end face using a thermistor probe in the bovine tissue, while delivering laser energy of over 200 and 500 J. Results: DDOFP was customized to secure the inner diameter of the 19-gauge needle catheter of 686 lm to be integrated as a clinical device. The round ball lens fiber tip minimized the back-burn effect caused by blood carbonization during surgery and induced front-spherical diffusion. DDOFP produced uniform light illumination with intensity difference of <10%. When DDOFP was bent with a small curvature <15 mm, the transmission intensity was consistent. Under high-power laser transmission, DDOFP was found to be robust to cracking or deformation. Conclusions: DDOFP was customized for pancreatic PDT with superior thermomechanical property and uniform light illumination at both the front-spherical and side-cylindrical areas. This is the smallest clinically available optical fiber per our knowledge and officially approved by the Korea Food and Drug Administration (item approval number: 17-516). DDOFP can contribute immensely toward the efficient delivery of pancreatic PDT and photothermal therapy. [ABSTRACT FROM AUTHOR]

Platyspondylic lethal skeletal dysplasia, Torrance type (PLSD-T), is one of the phenotypes of type II collagenopathy and is characteristic of severe bone growth disorder. This phenotype may limit the growth and expansion of the lungs, which is known to cause death from respiratory failure during or shortly after birth, but in few less severe cases, patients have been reported to have survived to adulthood. We have experienced a case of PLSD-T in a preterm infant who was delivered via cesarean section at the gestational age of 29 weeks 3 days, with a birth weight of 1.15 kg. Physical examination of the infant revealed characteristic findings of short arms and legs, small thorax, distended abdomen, and cleft palate. On the basis of the subsequent genetic testing, the patient had a heterozygous mutation in the encoded c-propeptide region of collagen, type II, alpha 1 (COL2A1), c.4335G>A (p.Trp1445*) in exon 52. This is the first case of PLSD-T diagnosed in Korea, and we hereby report the case. [ABSTRACT FROM AUTHOR]

Among 98 3-acyltetramic acid analogues, compounds 1c, 2c, 2f and 2g, showed >90% nematicidal activity against the pine wood nematode Bursaphelenchus xylophilus at a 10 μg/mL concentration. The nematicidal activities of compounds 1d, 1h, and 2k were a little lower at 88.0%, 85.8%, and 57.2% at a 10 μg/mL concentration, respectively. The nematicidal activity of emamection benzoate, widely used in Korea for the prevention of pine wilt disease, was 32.3% at a 10 μg/mL concentration. Other 3-acyltetramic acid analogues showed less than 30% nematicidal activity. A structure-activity relationship study indicated that the chain length of the C-acyl substituent was very important for high nematicidal activity. All active compounds had C13H27 or C11H23 acyl substituents, in two closely related groups with the common physicochemical properties of a polar surface area 57.6A², PSA (polar surface area) 7.8--8.6% and ClogP (calculated partition coefficient) 5.1--5.9 and a polar surface area 75--84A², PSA 11.1--11.6% and ClogP 4.7--5.1, respectively. Our study indicates that active 3-acyltetramic acid analogues could have potential as lead compounds for developing novel pine wood nematode control agents. [ABSTRACT FROM AUTHOR]

A 1:10 scale of a street canyon and courtyard was constructed to evaluate sound propagation when various vegetation treatments including trees, shrubs, vegetated facades, and green roofs were installed in the urban environment. Noise reductions in the street canyon and courtyard were measured for both single and combined vegetation treatments. Vegetated facades mitigated the overall noise level up to 1.6 dBA in the street canyon, and greening facades were effective to reduce low frequency noise levels below 1 kHz. Trees increased the noise level at high frequency bands to some extent in the street canyon, while the noise level over 1 kHz decreased in the courtyard after installing the street trees. This is because tree crowns diffused and reflected high frequency sounds into the street canyon. Green roofs offered significant noise abatement over 1 kHz in the courtyard, while the vegetated facade was effective to reduce noise levels at low frequencies. In terms of the integrated effects of vegetation treatments, a combined vegetation treatment was less effective than the sum of single treatments in the street canyon. The maximum noise reduction observed for all combinations of vegetation treatments provided 3.4 dBA of insertion loss in the courtyard. [ABSTRACT FROM AUTHOR]

The dynamics of cellular heat production and propagation remains elusive at a subcellular level. Here we report the first small molecule fluorescent thermometer selectively targeting the endoplasmic reticulum (ER thermo yellow), with the highest sensitivity reported so far (3.9%/°C). Unlike nanoparticle thermometers, ER thermo yellow stains the target organelle evenly without the commonly encountered problem of aggregation, and successfully demonstrates the ability to monitor intracellular temperature gradients generated by external heat sources in various cell types. We further confirm the ability of ER thermo yellow to monitor heat production by intracellular Ca2+ changes in HeLa cells. Our thermometer anchored at nearly-zero distance from the ER, i.e. the heat source, allowed the detection of the heat as it readily dissipated, and revealed the dynamics of heat production in real time at a subcellular level. [ABSTRACT FROM AUTHOR]

Successful identification of nodal metastases in patients with cancer is crucial to prescribe suitable treatment regimens that can improve recurrence-free survival. Although some new imaging technologies for nodal staging have been developed, such as nanoparticle-enhanced MRI and quantum-dot--based fluorescence imaging, sound technologies for intraoperative differentiation of metastatic and inflamed lymph nodes remain lacking. In this study, we illustrate the feasibility of using a macrophage-specific fluorescent probe (MFP) to visualize sentinel lymph nodes during surgery, highlighting abnormalities related to inflammation and tumor infiltration with signal enhancement and reduction methods using this technology. MFP was identified by high-throughput screening of fluorescent small-molecule libraries synthesized with a diversity-oriented approach. It selectively visualized monocyte and macrophage cell populations in vitro, by live-cell imaging and flow cytometry, as well as in vivo, for imaging-guided surgery. Collectively, this study provides preclinical proof of concept for an intraoperative imaging platform to accurately assess lymph node status, eliminating the need for invasive nodal dissections that can contribute to complications of cancer therapy. [ABSTRACT FROM AUTHOR]

Novel structures of an near-infrared (NIR) tetraarylazadipyrromethene (aza-BODIPY) series have been prepared. We designed the core structure containing two amido groups at the para-position of the aromatic rings. The amido group was incorporated to secure insensitivity to pH and to ensure a bathochromic shift to the NIR region. Forty members of aza-BODIPY compounds were synthesized by substitution of the acetyl group with commercial amines on the alpha bromide. The physicochemical properties and photostability were investigated and the fluorescence emission maxima (745~755 nm) were found to be in the near infrared (NIR) range of fluorescence. [ABSTRACT FROM AUTHOR]

We prepared a new library of 160 compounds by conjugation of a BODIPY core to a collection of aldehydes. This bbrary was screened against 52 biologic.!Ily relevant analytes and we identified one fluorescent sensor of fructose (Fructose Orange). Fructose Orange showed a 24-fold fluorescence increase upon recognition of fructose and an outstanding selectivity among 24 different saccharides. NMR 4 studies confirmed that five different binding interactions were formed between the sensor and fructose. Furthermore, Fructose Orange was applied to the quantification of fructose in soft drinks, being the most selective fluorescent sensor for fructose reported to date. [ABSTRACT FROM AUTHOR]

A practical solid-phase strategy for the synthesis of 5-2-oxopiperazines via N-acyliminium ion cyclization has been developed. A key step in the library synthesis is tandem acidolytic cleavage with subsequent in situ iminium formation, followed by stable enamide transformation. This approach is exemplified by the preparation of a 192-member pilot library using bromoacetal resins without further purification. [ABSTRACT FROM AUTHOR]

A novel and efficient strategy has been developed to synthesize privileged tetrahydro-1,4-benzodiazepines with excellent yields and purities; this synthetic pathway was established by the revitalization of the Leuckart–Wallach (LW) reaction via solid-phase synthesis. [ABSTRACT FROM AUTHOR]

Neurocutaneous melanosis (NCM) is a rare nonheritable congenital phakomatosis. NCM is characterized by large or multiple (>3) congenital nevi that are associated with benign and/or malignant melanocytic tumors of the leptomeninges. Approximately 10% of symptomatic patients with NCM have associated Dandy Walker complex (DWC), which seems to have an extremely poor prognosis. We report the case of a 7 year-old patient with multiple congenital NCM associated with DWC, who experienced a transient improvement in neurological symptoms including mental status and hemiparesis after intravenous immunoglobulin (IVIG) therapy. We suggest that the administration of IVIG may play a role in the treatment of symptomatic NCM. [ABSTRACT FROM AUTHOR]

Two-photon (TP) microscopy has an advantage for live tissue imaging which allows a deeper tissue penetration up to 1 mm comparing to one-photon (OP) microscopy. While there are several OP fluorescence probes in use for pancreatic islet imaging, TP imaging of selective cells in live islet still remains a challenge. Herein, we report the discovery of first TP live pancreatic islet imaging probe; TP-α (Two Photon-alpha) which can selectively stain glucagon secreting alpha cells. Through fluorescent image based screening using three pancreatic cell lines, we discovered TP-α from a TP fluorescent dye library TPG (TP-Green). In vitro fluorescence test showed that TP-α have direct interaction and appear glucagon with a significant fluorescence increase, but not with insulin or other hormones/analytes. Finally, TP-α was successfully applied for 3D imaging of live islets by staining alpha cell directly. The newly developed TP-α can be a practical tool to evaluate and identify live alpha cells in terms of localization, distribution and availability in the intact islets. [ABSTRACT FROM AUTHOR]

In 2010, symptoms of leaf and stem rot were observed on potted plants (Peperomia quadrangularis) in a greenhouse in Yongin, Korea. The causative pathogen was identified as Myrothecium roridum based on morphological data, internal transcribed spacer sequence analysis, and pathogenicity test. To our knowledge, this is the first report of M. roridum causing leaf and stem rot disease on R quadrangularis in Korea and elsewhere worldwide. [ABSTRACT FROM AUTHOR]