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Biomedical subjects

C C Hsu

Publications and source records attributed to C C Hsu.

At least 73 records · Page 4Linked to original sources
PubMed1999

Protein inhalation powders: spray drying vs spray freeze drying.

PURPOSE: To develop a new technique, spray freeze drying, for preparing protein aerosol powders. Also, to compare the spray freeze-dried powders with spray-dried powders in terms of physical properties and aerosol performance. METHODS: Protein powders were characterized using particle size analysis, thermogravimetric analysis, scanning electron microscopy, X-ray powder diffractometry, and specific surface area measurement. Aerosol performance of the powders was evaluated after blending with lactose carriers using a multi-stage liquid impinger or an Anderson cascade impactor. Two recombinant therapeutic proteins currently used for treating respiratory tract-related diseases, deoxyribonuclase (rhDNase) and anti-IgE monoclonal antibody (anti-IgE MAb), were employed and formulated with different carbohydrate excipients. RESULTS: Through the same atomization but the different drying process, spray drying (SD) produced small (approximately 3 microns), dense particles, but SFD resulted in large (approximately 8-10 microns), porous particles. The fine particle fraction (FPF) of the spray freeze-dried powder was significantly better than that of the spray-dried powder, attributed to better aerodynamic properties. Powders collected from different stages of the cascade impactor were characterized, which confirmed the concept of aerodynamic particle size. Protein formulation played a major role in affecting the powder's aerosol performance, especially for the carbohydrate excipient of a high crystallization tendency. CONCLUSIONS: Spray freeze drying, as opposed to spray drying, produced protein particles with light and porous characteristics, which offered powders with superior aerosol performance due to favorable aerodynamic properties.

Administration, Inhalation↗
PubMed1999

Performance of sonication and microfluidization for liquid-liquid emulsification.

The purpose of this research was to evaluate and compare liquid-liquid emulsions (water-in-oil and oil-in-water) prepared using sonication and microfluidization. Liquid-liquid emulsions were characterized on the basis of emulsion droplet size determined using a laser-based particle size analyzer. An ultrasonic-driven benchtop sonicator and an air-driven microfluidizer were used for emulsification. Sonication generated emulsions through ultrasound-driven mechanical vibrations, which caused cavitation. The force associated with implosion of vapor bubbles caused emulsion size reduction and the flow of the bubbles resulted in mixing. An increase in viscosity of the dispersion phase improved the sonicator's emulsification capability, but an increase in the viscosity of the dispersed phase decreased the sonicator's emulsification capability. Although sonication might be comparable to homogenization in terms of emulsification efficiency, homogenization was relatively more effective in emulsifying more viscous solutions. Microfluidization, which used a high pressure to force the fluid into microchannels of a special configuration and initiated emulsification via a combined mechanism of cavitation, shear, and impact, exhibited excellent emulsification efficiency. Of the three methodologies, sonication generated more heat and might be less suitable for emulsion systems involving heat-sensitive materials. Homogenization is in general a more effective liquid-liquid emulsification method. The results derived from this study can serve as a basis for the evaluation of large-scale liquid-liquid emulsification in the microencapsulation process.

Emulsions↗
PubMed1999

Surgical outcome of traumatic intracranial hematoma at a regional hospital in Taiwan.

BACKGROUND: To report the experience in the management of 489 consecutive patients with traumatic intracranial hematoma and determine the prognostic factors. METHODS: All patients were classified into three groups based on the number of operations for each case. A total of 538 operations were performed for evacuation of 720 intracranial hematomas. RESULTS: The most common cause of injury was motor vehicular traffic crashes (68.7%) and most victims were motorcyclists (40.1%). The most common type of lesion was acute epidural hematoma (31.0%). The overall mortality rate was 9.6%, and the complication rate was 11.2%. Follow-up assessment of 480 patients revealed that 270 (56.2%) patients made a good recovery, 99 (20.6%) were moderately disabled, 32 (6.7%) were severely disabled, 21 (4.4%) were vegetative, and 58 (12.1%) had died. CONCLUSION: The surgical outcome was significantly correlated with the score of the Glasgow Coma Scale, pupillary reactivity, number of operations, and type of lesion.

Adolescent↗
PubMed1999

Chloracne, goiter, arthritis, and anemia after polychlorinated biphenyl poisoning: 14-year follow-Up of the Taiwan Yucheng cohort.

In 1979, a mass poisoning involving 2,000 people occurred in central Taiwan from ingestion of cooking oil contaminated by polychlorinated biphenyls (PCBs) and polychlorinated dibenzofurans (PCDFs). We studied the prevalence of medical conditions in the exposed individuals and in a neighborhood control group. Starting with a registry of the exposed individuals from 1983, we updated the addresses of exposed individuals and identified a control group matched for age, sex, and neighborhood in 1979. In 1993, individuals 30 years of age or older were interviewed by telephone. We obtained usable information from 795 exposed subjects and 693 control subjects. Lifetime prevalence of chloracne, abnormal nails, hyperkeratosis, skin allergy, goiter, headache, gum pigmentation, and broken teeth were observed more frequently in the PCB/PCDF-exposed men and women. The exposed women reported anemia 2. 3 times more frequently than controls. The exposed men reported arthritis and herniated intervertebral disks 4.1 and 2.9 times, respectively, more frequently than controls. There was no difference in reported prevalences of other medical conditions. We conclude that Taiwanese people exposed to high levels of PCBs and PCDFs reported more frequent medical problems, including skin diseases, goiter, anemia, and joint and spine diseases.

Acne Vulgaris↗
PubMed1999

Evaluation of ocular arterial changes in glaucoma with color Doppler ultrasonography.

The purpose of this study was to evaluate hemodynamic changes of the retrobulbar vasculature caused by different intraocular pressures with color Doppler ultrasonography. Fifty normal eyes in 25 patients, 13 patients with normal tension glaucoma, and 19 patients with acute glaucoma and increased intraocular pressure (greater than 30 mm Hg) were enrolled in this study. In 15 of 19 patients with acute glaucoma patients, follow-up color Doppler ultrasonography was also undertaken after laser peripheral iridectomy when the intraocular pressure had returned to normal. The peak systolic velocity, end diastolic velocity, resistive index, time average maximum velocity, and pulsatility index were compared in different vessels, including the central retinal artery, lateral posterior ciliary artery, medial posterior ciliary artery, and ophthalmic artery in each orbit. The peak systolic velocity, end diastolic velocity, and time average maximum velocity of the central retinal artery were significantly lower (P<0.01) in acute glaucoma patients than in the control group. The resistive index and pulsatility index of the central retinal artery were significantly higher (P<0.01) in acute glaucoma patients than in the control group. The end diastolic velocity of the lateral and medial posterior ciliary arteries was significantly lower in patients with acute glaucoma than in the control group, and the resistive index and pulsatility index of both of these arteries were significantly higher (P<0.001) in patients with acute glaucoma than in the control group. However, no statistical significantly differences were found in the peak systolic velocity or time average maximum velocity in either of the posterior ciliary arteries; similarly, no statistically significant differences were noted in any of the parameters in the ophthalmic artery between the control group and the group with acute glaucoma. The pulsatility index of the central retinal artery and of the lateral and medial posterior ciliary arteries was significantly lower (P<0.01) in acute glaucoma patients after laser therapy than in acute glaucoma patients before laser therapy. The resistive index of both posterior ciliary arteries was also significantly lower (P<0.004) in acute glaucoma patients after laser therapy than before laser therapy. All parameters for all vessels examined among the normal subjects, the patients with normal tension glaucoma, and the patients with acute glaucoma after laser therapy when the intraocular pressure had returned to normal showed no statistically significant differences. Color Doppler ultrasonography is a good modality for both imaging and studying the hemodynamics of the perioptic nerve vessels.

Aged↗
PubMed1999

Alternative and effective treatment of shoulder ganglion cyst: ultrasonographically guided aspiration.

The therapeutic effect of ultrasonographically guided aspiration of a ganglion cyst of the shoulder is evaluated. Fifteen patients (nine male, six female) with chronic shoulder pain were enrolled in this study. Each patient was referred to rule out rotator cuff lesion. The ultrasonographic examination showed an anechoic cystic lesion in the shoulder region in every patient and abnormality of the rotator cuff in only four patients. Under ultrasonographic guidance, an 18 gauge needle was inserted into the cyst to aspirate the fluid. Initial sonographic imaging showed the cyst, which appeared as a localized fluid accumulation and was located between the deltoid muscle and the subscapularis tendon in seven patients, between the deltoid muscle and the biceps tendon in one patient, below the coracoacromial ligament in five patients, and over suprascapular notch area in one patient. The ganglion cysts ranged in size from 3.5 to 30 mm. The amount of aspirated fluid in each cyst varied from 0.4 to 12 ml (mean, 2.6 ml +/- 3.1) with a clear or light yellowish color and a jelly-like appearance. No major complications occurred during or after this procedure. The symptom (pain) was improved after sonographically guided aspiration in each patient. Follow-up study showed complete relief of pain in four patients, marked improvement in nine patients, and mild improvement but still persistent shoulder pain in two patients. Duration of follow-up study ranged from 2 to 24 months (mean, 6.4 months +/- 6.9). The success rate for sonographically guided aspiration was 86% on the basis of marked symptom improvement or relief. Ultrasonographically guided aspiration of shoulder ganglion cysts is an effective procedure in the management of shoulder pain caused by ganglion cysts.

Adult↗
PubMed1999

Intracerebral hemorrhage caused by cerebral amyloid angiopathy: a case report.

Cerebral amyloid angiopathy (CAA) accounts for approximately 10% of spontaneous intracerebral hemorrhages (ICH), and typically occurs in the cortex and subcortical white matter. It is characterized by the deposition of amyloid fibrils in the leptomeningeal, cortical and subcortical arteries. Pathologically, amyloid is stained pink with Congo red and shows yellow-green birefringence when viewed under polarized light. Although there have been many reports of CAA in the literature, it has rarely been described in Taiwan. This is the report of a case of a 75-year-old man with ICH caused by CAA. The postoperative course was uneventful. The incidence of this disease increases with age. The authors, therefore, suggest conducting a brain biopsy and special stain for CAA in each operative case of spontaneous ICH, especially in the elderly.

Aged↗
PubMed1999

Early detection of unilateral occlusion of duplicated uterus with ipsilateral renal anomaly in young girls: two case reports with three-dimensional sonography.

Early detection of unilateral occlusion of duplicated uterus with ipsilateral renal anomaly is very rare and difficult. We present two cases using three-dimensional (3D) sonography as a noninvasive, comprehensive and effective method in the early detection of this syndrome in the young girls. The two young, unmarried girls had irregular abdominal discomfort and pain during the recent few years. Series traditional study showed pelvic lesions, but failed to recognized the definite cause. With 3D sonography, we demonstrated the rare congenital anatomic relationships and gave the optimal management. The girls recovered soon and had uneventful OPD follow-up. Application of 3D sonography in the suspected young girls avoids unnecessary examinations and invasive interventions, decreases the morbidity and improves their quality of life.

Abnormalities, Multiple↗
PubMed1999

Detection of human papilloma virus and Epstein-Barr virus DNA in nasopharyngeal carcinoma by polymerase chain reaction.

Nasopharyngeal carcinoma (NPC) is an unique epithelial malignancy which occurs at a high frequency in certain regions of Southeast Asia. Human papilloma virus (HPV) and Epstein-Barr virus (EBV) have both been identified in tissue specimens from NPC. Nevertheless, the association between viral infection and NPC remains unclear. The purpose of this study was to demonstrate that simultaneous infection with EBV and HPV can occur in NPC. Eighty-eight fresh tissue samples which contained sufficient and adequate DNA from patients with histologically confirmed NPC were examined for the existence of HPV and EBV DNA by polymerase chain reaction (PCR). The results showed that HPV and EBV DNA were detected in 51% and in 83% of the specimens, respectively. Coexistence of EBV and HPV in NPC was found in 42% of the samples. The "high risk" types including HPV-16 and HPV-18 accounted for 67% of 45 HPV positive samples. Furthermore, 80% of HPV-16 or HPV-18 positive samples also contained EBV DNA. Our findings suggest that coexistence of EBV and "high risk" HPV-16 or HPV-18 infection may be an important factor in the pathogenesis of NPC.

DNA, Viral↗
PubMed1999

Brunner's gland hamartomas: report of three cases.

Brunner's gland hamartoma is a rare duodenal tumor, which grew larger than 2 cm in diameter in a very limited number of cases. Since the first description in a patient with fatal duodenal intussusception by Cruveilhier in 1835, approximately 143 cases have been reported in the English literature, and only 25 cases had tumor growth to more than 2 cm in diameter. To the best of our knowledge, only 4 cases have been reported in Taiwan. We present three of Brunner's gland hamartomas. In one patient the tumor was located on the secondary portion of the duodenum, which presented with massive tumor bleeding and measured 3.0 cm in diameter. The other two were both located on the duodenal bulb, which presented with abdominal pain and measured 2.0 and 1.3 cm in diameter, respectively. One of the patients received endoscopic ultrasonography which showed specific findings. Two patients received laparotomy and tumor excision; the other one received endoscopic polypectomy. All 3 patients recovered well without any complications.

Brunner Glands↗
PubMed1999

Recurrent inverted papilloma: diagnosis with pharmacokinetic dynamic gadolinium-enhanced MR imaging.

BACKGROUND AND PURPOSE: Dynamic gadolinium-enhanced MR imaging has been used successfully to identify post-treatment recurrence or postoperative changes in rectal and cervical carcinoma. Our purpose was to evaluate the usefulness of dynamic gadolinium-enhanced MR imaging for distinguishing recurrent inverted papilloma (IP) from postoperative changes. METHODS: Fifteen patients with 20 pathologically proved lesions (recurrent IP, 12; fibrosis or granulation tissue, eight) were enrolled in the study. Three observers, blinded to pathologic results, independently evaluated conventional MR images, including T1-weighted (unenhanced and postcontrast), proton-density-weighted, and T2-weighted spin-echo images. Results then were determined by consensus. Dynamic images were obtained using fast spin-echo sequences at 5, 30, 60, 90, 120, 150, 180, and 300 seconds after the injection of gadolinium-diethylene-triamine penta-acetic acid. Time-signal intensity curves of suspected lesions were analyzed by a pharmacokinetic model. The calculated amplitude and tissue distribution time were used to characterize tissue, and their values were displayed as a color-coded overlay. RESULTS: T2-weighted images yielded a sensitivity of 67%, a specificity of 75%, and an accuracy of 70% in the diagnosis of recurrent IP. Contrast-enhanced T1-weighted images yielded a sensitivity of 75%, a specificity of 50%, and an accuracy of 65%. Pharmacokinetic analysis showed that recurrent IP had faster (distribution time, 41 versus 88 seconds) and higher (amplitude, 2.4 versus 1.2 arbitrary units) enhancement than did fibrosis or granulation tissue. A cut-off of 65 seconds for distribution time and 1.6 units for amplitude yielded a sensitivity of 100% and a specificity of 100% for diagnosing recurrent IP. CONCLUSION: Dynamic MR imaging can differentiate accurately recurrent IP from postoperative changes and seems to be a valuable diagnostic tool.

Adult↗
PubMed1999

The effective dose of dexamethasone for antiemesis after major gynecological surgery.

UNLABELLED: This double-blind, randomized, placebo-controlled study evaluated the minimum effective dose of dexamethasone for postoperative antiemesis. One-hundred fifty women scheduled for major gynecological surgery were randomly assigned to receive dexamethasone 10 mg (D10), 5 mg (D5), 2.5 mg (D2.5), 1.25 mg (D1.25), or placebo (P) before the induction of general anesthesia. A standardized general anesthesia technique was used. Postoperative pain was treated with bolus IV doses of morphine via a patient-controlled analgesia device. Patients were assessed for incidence of vomiting at 4, 8, 12, and 24 h after surgery. A total of 6, 6, 8, 15, and 19 patients in Groups D10, D5, D2.5, D1.25, and Group P experienced vomiting at least once within the first postoperative 24 h, respectively. Dexamethasone 10 mg, 5 mg, and 2.5 mg was more effective than dexamethasone 1.25 mg or placebo for antiemesis (P < 0.05). The difference in antiemetic effect among the 10 mg, 5 mg, and 2.5 mg groups was similar. The results suggest that 2.5 mg is the minimum effective dose of dexamethasone for postoperative antiemesis in patients undergoing general anesthesia for major gynecological surgery. IMPLICATIONS: Although dexamethasone is effective for antiemesis, major side effects may accompany its perioperative use. To achieve the best antiemesis with the fewest side effects, dexamethasone 10 mg, 5 mg, 2.5 mg, and 1.25 mg were compared with placebo in surgical patients. We found 2.5 mg to be the minimum effective dose without discernible side effects.

Anesthesia, General↗
PubMed1998

An ELISA for RNA helicase activity: application as an assay of the NS3 helicase of hepatitis C virus.

A convenient enzyme-linked immunosorbent assay (ELISA) for RNA helicase activity was developed with principles similar to the standard assay. The helicase ELISA utilizes a non-radioactive double-stranded substrate with a biotin-labeled template (long) strand hybridized to a digoxigenin (DIG)-labeled release (short) strand. The template strand binds to the wells of streptavidin-coated microtiter plates (SA-MTP) where the helicase catalyzes the unwinding reaction. Substrate not unwound retains the DIG-labeled release strand and is detected using anti-DIG coupled to horseradish peroxidase. Chromogenic detection follows. Absorbance measurement allows determination of unwinding efficiency of reactions. To demonstrate effectiveness, the ELISA-based assay was used to study the unwinding activity of the hepatitis C virus (HCV) NS3 helicase. Using a known inhibitor of NS3 helicase activity and two mutant HCV helicases, the ability of the assay to screen potential anti-helicase drugs and putative helicases is illustrated. The helicase ELISA is more convenient than the standard helicase assay and is especially suited for the testing of large numbers of samples.

Catalytic Domain↗
PubMed1998

Spray-drying performance of a bench-top spray dryer for protein aerosol powder preparation.

The objective of this work was to improve a bench-top spray dryer's efficiency in both production recovery and throughput for preparing protein aerosol powders. A Büchi mini-spray dryer was used to prepare the powders of recombinant humanized anti-IgE antibody. The resulting powder's physical properties such as particle size, residual moisture, and morphology, along with its recovery and production rate was the basis of this development work. Mass balance suggests that approximately 10-20% of powder was lost in the exhaust air, consisting primarily of particles less than 2 micrometer. Also, significant loss (20-30%) occurred in the cyclone. Attempts were made to improve product recovery in the receiving vessel using dual-cyclone configurations, different cyclone designs, cyclones with anti-static treatment, and different receiver designs. System modifications such as replacing the original bag-filter unit with a vacuum system effectively reduced drying air flow resistance, allowing the protein to be dried at a lower inlet air temperature and the production scale to be increased. We concluded that the modified spray-drying system is advantageous over the original bench-top spray dryer. This improvement will be beneficial to early-stage research and development involving high-valued protein powders.

Aerosols↗
PubMed1998

Lead-induced changes in spermatozoa function and metabolism.

The relationships between sperm reactive oxygen species (ROS) generation, the capacitation process and acrosome reaction, and the spermoocyte penetration rate (SOPR) were investigated to understand the effect of lead toxicity on sperm functions and the mechanisms of these effects. Male Sprague-Dawley rats received weekly intraperitoneal injections of 20 mg or 50 mg lead acetate/kg or 20 mg or 50 mg sodium acetate/kg (control) for 6 wk. Serum testosterone was measured by radioimmunoassay. In cauda epididymal spermatozoa, the chemiluminescence was measured to evaluate the sperm ROS generation. Chlortetracycline fluorescence assay was used to study the status of capacitation and acrosome reaction on fresh cauda epididymal spermatozoa and after 2, 4, or 24 h of incubation with 5 mg/ml bovine serum albumin. In lead-exposed rats, the serum testosterone levels were reduced, and the percentage of capacitation and the chemiluminescence were significantly increased in fresh cauda epididymal spermatozoa. The serum testosterone levels were negatively associated with the percentage of acrosome-reacted spermatozoa. Sperm chemiluminescence was positively correlated with the percentage of both capacitated and acrosome-reacted spermatozoa. The SOPR was negatively associated with the percentage of both capacitated and acrosome-reacted spermatozoa. In summary, this study showed that male rats exposed to lead had decreased serum testosterone levels and that this metal produced early onset of capacitation by one of the pathways of ROS generation. These effects might consequently result in premature acrosome reaction and reduced zona-intact oocyte-penetrating capability.

Acrosome↗
PubMed1998

Effects of vitamin E and/or C on reactive oxygen species-related lead toxicity in the rat sperm.

This study was undertaken to investigate whether treatment with vitamin E (VE) and/or vitamin C (VC) protects rat sperm by inhibiting reactive oxygen species generation induced by lead (Pb) exposure. Male Sprague-Dawley rats were assigned to the following five groups: vitamin-unsupplemented; 150 mg VE/kg chow supplemented; 300 mg VE/kg chow supplemented; 500 mg VC/l drinking water supplemented and 150 mg VE/kg chow + 500 mg VC/l drinking water supplemented group. Rats in each group were divided into Pb-unexposed and Pb-exposed subgroups, received weekly intraperitoneal injection of 10 mg sodium acetate or 10 mg Pb acetate/kg for 6 weeks, respectively. The blood and sperm Pb levels were analyzed by graphite furnace atomic absorption spectrophotometer. Chemiluminescence was measured to evaluate the generation of sperm reactive oxygen species (ROS). Motility and sperm-oocyte penetration rate (SOPR) were measured. In Pb-unexposed rats, epididymal sperm counts, motility, ROS, and SOPR were not different in the five supplemented groups. Lead exposure might decrease the defense capacity of sperm to the oxidative stress and therefore elevate the ROS generation, reduce sperm motility, and reduce SOPR. Supplementation with VE and/or VC reduced ROS generation, prevented loss of motility and capacity of oocyte penetration in Pb-exposed rats. This study suggests that supplementation with VE and/or VC inhibits Pb-related ROS generation, protects spermatozoa from loss of motility and oocyte penetration capability.

Animals↗
PubMed1998

The role of three-dimensional ultrasonographic images in ovarian measurement.

OBJECTIVE: To determine whether three-dimensional ultrasonography can increase the ability to evaluate the ovary and follicles, especially in women with polycystic ovary disease (PCOD). DESIGN: Prospective clinical study. SETTING: University hospital endocrine and infertility center. PATIENT(S): Sixty-six patients undergoing routine gynecologic evaluation were divided into two groups: the normal control group consisted of 22 patients, and there were 44 patients with PCOD. INTERVENTION(S): Three-dimensional ultrasonography was performed to store and document whole volumes of the ovaries for evaluation. MAIN OUTCOME MEASURE(S): Three perpendicular planes of bilateral ovaries are rotatable to obtain the largest dimensions. The three-dimensional volume was measured using the trapezoid formula. RESULT(S): The ovaries of the patients with PCOD were larger in size, area, and volume than those of normal controls. CONCLUSION(S): Stroma and volume determinations can be obtained more accurately by three-dimensional images than by traditional ultrasonography. Three-dimensional ultrasonography not only facilitates noninvasive evaluation and volume calculation but also completes the examination in a short time without increasing patient discomfort.

Adult↗