Biodegradable Polymer-Based Drug-Delivery Systems for Ocular Diseases.

Ocular drug delivery is a challenging field due to the unique anatomical and physiological barriers of the eye. Biodegradable polymers have emerged as promising tools for efficient and controlled drug delivery in ocular diseases. This review provides an overview of biodegradable polymer-based drug-delivery systems for ocular diseases with emphasis on the potential for biodegradable polymers to overcome the limitations of conventional methods, allowing for sustained drug release, improved bioavailability, and targeted therapy. Natural and synthetic polymers are both discussed, highlighting their biodegradability and biocompatibility. Various formulation strategies, such as nanoparticles, hydrogels, and microemulsions, among others, are investigated, detailing preparation methods, drug encapsulation, and clinical applications. The focus is on anterior and posterior segment drug delivery, covering glaucoma, corneal disorders, ocular inflammation, retinal diseases, age-related macular degeneration, and diabetic retinopathy. Safety considerations, such as biocompatibility evaluations, in vivo toxicity studies, and clinical safety, are addressed. Future perspectives encompass advancements, regulatory considerations, and clinical translation challenges. In conclusion, biodegradable polymers offer potential for efficient and targeted ocular drug delivery, improving therapeutic outcomes while reducing side effects. Further research is needed to optimize formulation strategies and address regulatory requirements for successful clinical implementation.

Diagnosis and Treatment of Central Serous Chorioretinopathy in Patients with Scleritis.

Central serous chorioretinopathy (CSCR) is characterized by central neurosensory retinal detachment from the retinal pigment epithelium. While the association between CSCR and steroid use is widely recognized, it is difficult to distinguish whether the subretinal fluid (SRF) in ocular inflammatory disease results from steroid use or an inflammation-related uveal effusion. We report the case of a 40-year-old man who presented to our department with intermittent redness and dull pain in both eyes that had persisted for three months. He was diagnosed with scleritis with SRF in both eyes and steroid therapy was started. Inflammation improved with steroid use, but SRF increased. This indicated that the fluid was not caused by the posterior scleritis-related uveal effusion but by steroid use. SRF and clinical symptoms subsided after steroids were discontinued completely and immunomodulatory therapy was initiated. Our study highlights that steroid-associated CSCR must be considered in the differential diagnosis of patients with scleritis, and prompt diagnosis with an immediate shift from steroids to immunomodulatory therapy can resolve SRF and clinical symptoms.

Unveiling Novel Structural Biomarkers for the Diagnosis of Glaucoma.

Glaucoma, a leading cause of irreversible blindness, poses a significant global health burden. Early detection is crucial for effective management and prevention of vision loss. This study presents a collection of novel structural biomarkers in glaucoma diagnosis. By employing advanced imaging techniques and data analysis algorithms, we now can recognize indicators of glaucomatous progression. Many research studies have revealed a correlation between the structural changes in the eye or brain, particularly in the optic nerve head and retinal nerve fiber layer, and the progression of glaucoma. These biomarkers demonstrate value in distinguishing glaucomatous eyes from healthy ones, even in the early stages of the disease. By facilitating timely detection and monitoring, they hold the potential to mitigate vision impairment and improve patient outcomes. This study marks an advancement in the field of glaucoma, offering a promising avenue for enhancing the diagnosis and possible management.

Bifunctional NbS2-Based Asymmetric Heterostructure for Lateral and Vertical Electronic Devices.

Structural asymmetry of materials plays a crucial role in developing multipurpose devices. Layered metallic transition metal dichalcogenides (MTMDCs) have been proposed as promising materials in electronics. However, they are still subject to native surface oxidation, limiting their practical applications. Combination of surface protection and native surface oxidation of MTMDCs will create asymmetric structures for devices but has yet to be explored. Here, we report a bifunctional NbS2-based vertical heterostructure derived from epitaxially grown NbS2 on MoS2 followed by a natural oxidation (MoS2-NbS2-NbOx), which simultaneously exhibits both high-efficiency tunneling conductive and memristive surfaces. With the tunneling conductive surface, the heterostructure functions as nearly ohmic contact electrodes with a two-dimensional (2D) channel in lateral transistors, delivering an enhanced mobility ∼140 times higher than that of the exfoliated NbS2-contacted device. With the memristive surface, the heterostructure can be used to build high-performance lateral or vertical memristors with low working voltages and synaptic functions. By combining both types of surfaces, a memristor array for nonvolatile memory is further developed. Moreover, the memristors show a good endurance for 2000 cycles of bending as flexible devices. The bifunctional heterostructure based on NbS2 offers a strategy toward the future applications of layered metallic materials.

Effects of all-trans retinoic acid on Th1- and Th2-related chemokines production in monocytes.

Low vitamin C and reduced alpha-carotene intake are associated with increased asthma risk in children. In addition, mean serum vitamin A concentrations are significantly lower in asthmatic children than in controls. All-trans retinoic acid (ATRA) is a derivative of vitamin A. Macrophage-derived chemokine (MDC) is a T helper cell-type 2 (Th2)-related chemokine involved in the recruitment of Th2 cells toward inflammatory sites. On the other hand, Th1-related chemokine, interferon-inducible protein 10 (IP-10)/CXCL10 is also important in allergic inflammation. Both Th1- and Th2-related chemokines play an important role in allergic asthma. To survey whether ATRA and ascorbic acid effect Th1- and Th2-related chemokine expression in monocytes. To test this, THP-1 cells were pre-treated with ATRA or ascorbic acid and stimulated by lipopolysaccharide (LPS) or poly I:C. Supernatants were measured for Th2-related (MDC) and Th1-related (IP-10) chemokine concentrations by ELISA. The effects of ATRA on mitogen-activated protein kinase (MAPK) and NFkb were evaluated with Western blotting. After stimulation, ATRA significantly down-regulated MDC and IP-10 in a dose-dependent manner. Similarly, ascorbic acid reduced the LPS-induced changes in MDC but only with a high dose. However, asorbic acid had no effect on IP-10 changes either induced by LPS or poly I:C. RT-PCR showed ATRA inhibited IP-10 expression through decreasing the level of transcription. Furthermore, ATRA suppressed the expression of LPS-stimulated c-Raf, MKK1/2 and ERK expression of THP-1 cells. In conclusion, ATRA suppressed Th2- and Th1-related chemokines expression in THP-1 cells, at least in part via the c-Raf-MKK1/2-ERK/MAPK pathway.

Coil embolization of pulmonary sequestration in two infants--A safe alternative management.

Pulmonary sequestration is a rare congenital anomaly with nonfunctioning lung tissue, for which the arterial blood supply is usually derived from the thoracic or abdominal aorta. Surgical resection is the conventional treatment for pulmonary sequestration. The arterial embolization of pulmonary sequestration is an alternative technique and a less invasive treatment than conventional surgical resection. Here, we report two infants with intralobar and extralobar types of pulmonary sequestration, successfully treated with coil embolization of the feeding artery without any complications.

Congenital long QT syndrome with functionally impaired atrioventricular conduction: successful treatment by mexiletine and propranolol.

Congenital long QT syndrome (LQTS) with atrioventricular block is a rare and malignant arrhythmia, which usually responds poorly to traditional beta-blocker therapy. We describe a male neonate with LQTS with ventricular tachycardia and 2:1 atrioventricular block. This patient's sister had similar presentation and died suddenly at the age of 8 months despite beta-blocker and pacemaker therapy. Our patient responded to a combination of sodium channel blocker (mexiletine) and beta-blocker (propranolol) therapy. He was asymptomatic during a 2-year follow-up period. This case suggests that propranolol combined with mexiletine might be useful in the treatment of patients with LQTS with atrioventricular block.

Diverticulum of the right ventricle associated with pulmonary stenosis, rhabdomyoma and Wolff-Parkinson-White syndrome.

Congenital cardiac diverticulum is a rare anomaly that may present as an isolated lesion or in association with other malformations. Diverticulum of the left ventricle is more common than that of the right ventricle. We report a case of cardiac diverticulum over the right ventricular outflow tract and associated pulmonary stenosis, right atrial rhabdomyoma, and Wolff-Parkinson-White syndrome in a 9-month-old boy. The delta wave disappeared after removal of the atrial rhabdomyoma.

Intrapulmonary thrombolytic therapy in a child with acute pulmonary embolism due to primary antiphospholipid syndrome.

Pulmonary embolism (PE) is a rare but life-threatening condition, which needs emergent treatment in children. Though anticoagulation is the standard treatment for PE, recent studies revealed intrapulmonary thrombolytic therapy may produce more rapid clot lysis and less systemic complications in adult patients. We reported a 10-year-old girl who had diffused multiple pulmonary emboli due to primary antiphospholipid syndrome. The thrombi persisted in spite of intravenous heparin infusion for 3 days, which resolved quickly after intrapulmonary streptokinase infusion for 12 hours.

Cardiac tumors in infants and children.

Cardiac tumors in infants and children are extremely rare. Their clinical manifestations vary widely from asymptomatic presentations to life-threatening cardiac events. Improvements in diagnostic techniques, such as those offered by echocardiography, have made early detection of cardiac masses possible, with or without the presence of clinical symptoms. Fifteen pediatric cases of cardiac tumor were diagnosed at our institution between July 1989 and July 2002 (male-female ratio, 10:5; age range, one day to nine years). Eleven of the cases involved primary cardiac tumors [rhabdomyoma (n = 10) and fibroma (n = 1)]. Ninety percent of the rhabdomyomas (9/10) were associated with tuberous sclerosis. Four of the fifteen cases were secondary metastatic tumors [hepatoblastoma (n = 2), hepatoma (n = 1) and rhabdomyosarcoma (n = 1)]. Clinical manifestations of the cardiac tumors included shortness of breath (n = 5), seizure (n = 4), cardiac murmur (n = 6), and cyanosis (n = 3). Surgery was performed for three of 11 patients with primary cardiac tumor (27%) due to severe obstruction of flow (n = 2) and other cardiac defects (n = 1). The primary cardiac tumor spontaneously regressed in five of the tuberous sclerosis patients. All four of the patients with secondary cardiac tumors continued to receive chemotherapy, and only one of them subsequently experienced regression. Based on our experiences, we conclude that: 1) rhabdomyoma is the most common primary cardiac tumor in children; 2) most pediatric tumors are associated with tuberous sclerosis; 3) clinical presentation is determined by the tumor size and number of tumors, and whether expansion of the malignancy has resulted in cardiac blood-flow obstruction; 4) there is a strong possibility of regression of the primary cardiac tumor, with surgery recommended only when cardiac symptoms are severe; and, 5) unless there is a significant obstruction of blood flow, chemotherapy is still the treatment of choice for secondary cardiac tumors.

Cardiopulmonary manifestations of fulminant enterovirus 71 infection.

BACKGROUND: The pathogenesis of acute pulmonary edema and cardiac collapse after enterovirus 71 (EV71) infection are not completely understood. OBJECTIVE: To determine the hemodynamic features and the mechanism of pulmonary edema (PE) after EV71 infection by direct intracardiac monitoring. DESIGN: Prospective clinical and laboratory study at a tertiary medical center. PARTICIPANTS: Five consecutive infants, ages 2 to 13 months, with EV71 infection-proved by viral isolation in 4 and antibody in 1-with PE were enrolled. The clinical characteristics were systemically assessed. Hemodynamic profiles were determined every 4 hours by simultaneously implanted pulmonary arterial and central venous catheters during the acute stage. RESULTS: Magnetic resonance imaging revealed that all 5 infants had brainstem lesions. All patients had tachycardia and hyperthermia. Transient systolic hypertension was noted in 1 patient, and 1 presented with hypotension. Pulmonary artery pressure in all 5 infants was normal or mildly elevated (26-31 mm Hg), and central venous pressure ranged from 10 to 22 mm Hg. Pulmonary artery occlusion pressures were normal or slightly elevated (13-16 mm Hg). Systemic and pulmonary vascular resistances were transiently increased in only 1 patient. The stroke volume index decreased to 15.3 to 35.7 mL/M2 (normal: 30-60 mL/M2), but because of the elevated heart rate, the cardiac index did not decrease. All hemodynamics normalized within days. CONCLUSION: Fulminant EV71 infection may lead to severe neurologic complications and acute PE. The acute PE and cardiopulmonary decompensation in EV71 infection are not directly caused by viral myocarditis. The mechanism of PE may be related to increased pulmonary vascular permeability caused by brainstem lesions and/or systemic inflammatory response instead of increased pulmonary capillary hydrostatic pressure.