Chitosan microparticle preparation for controlled drug release by response surface methodology

The objectives were to investigate the effects of formulation variables on the release of drug and to optimize the formulation of chitosan microparticles loaded with drug for controlled release using response surface methodology. Chitosan microparticles were prepared by dropping a chitosan solution into sodium tripolyphosphate (TPP) through ionic cross-linking. The release behaviour of felodipine as a model drug was affected by preparation variables. A central composite design was used to evaluate and optimize the effect of preparation variables, chitosan concentration (X1), the pH of the TPP solution (X2) and cross-linking time (X3) on the cumulative per cent drug release (Y) in 24 h. Chitosan concentration and cross-linking time affected negatively the release of felodipine, while the pH of the TPP did so positively and was the highest influential factor. The optimum rate of drug release, 100% in 24 h, was achieved at 1.8% chitosan concentration, a pH 8.7 for the TPP solution and 9.7 min cross-linking time.

Characteristics of granular sludge in a single upflow sludge blanket reactor treating high levels of nitrate and simple organic compounds

Simultaneous denitrification and methanogenesis were accomplished in a single upflow sludge blanket (USB) reactor. More than 99% and 95% of nitrate and chemical oxygen demand (COD) removal rates were obtained at a loading of 600 mg NO3-N/L x d and 3,300 mg COD/L x d, respectively. The specific denitrification rate (SDR) increased as COD/NO3-N ratios decreased. Maximum SDR with acetate could reach 1.05 g NO3-N/gVSS x d. Significant sludge flotation was observed at the top of the reactor due to the change of microbial composition and the formation of hollow granules. Granules became fluffy and buoyant due to the growth of denitrifiers. Microscopic examination showed that granules exhibited layered structure and they were mainly composed of Methanosarcina sp., Pseudomonas sp., and rod-shaped bacteria.

Vanilloid receptor VR1-positive afferents are distributed differently at different levels of the rat lumbar spinal cord

The vanilloid receptor VR1 renders a group of primary afferents that express it sensitive to noxious heat and capsaicin, and is thus an important marker for nociceptors. We use double immunofluorescence and confocal microscopy to show that the density of VR1-positive fibers and boutons in the dorsal horn increases progressively from spinal segments L4 to L6 and that the colocalization of VR1 with the neuropeptide substance P (SP) in lamina I and along the lateral collateral path, where the majority of visceral afferents terminate, is negligible at L4, but substantial at L6. We conclude that VR1 is expressed by visceral afferents to the lower lumbar spinal cord in the rat, which also express SP.

Trends in prescribing proton pump inhibitors in Taiwan: 1997 - 2000

OBJECTIVE

The prescribing of proton pump inhibitors (PPIs) had increased greatly in recent years worldwide. Aim of our study was to analyze the utilization patterns of PPIs within the National Health Insurance program in Taiwan from 1997 - 2000.

MATERIAL AND METHOD

The systemic sampling data-sets from the National Health Insurance Research Database served as data sources. Units of measurement for PPIs were numbers of prescription items and defined daily doses (DDDs). To estimate the proportion of the population treated daily with PPIs, numbers of DDDs per 1,000 inhabitants per day were calculated. In order to realize the role of PPIs in treating Helicobacter pylori-related disorders, we also analyzed various combined prescriptions of PPIs with amoxicillin, clarithromycin, metronidazole, tetracycline and bismuth.

RESULTS

In the study period, PPI prescriptions increased nearly 2-fold at the outpatient sector and more than 3-fold at the inpatient sector. Men received more PPI prescriptions, as a whole, than women. Most PPIs were prescribed at the outpatient sector: 93.9% in 1997, 92.3% in 1998, 90.4% in 1999 and 87.3% in 2000. The numbers of DDDs per 1,000 inhabitants per day for all kinds of PPIs were 0.59, 0.78, 1.07, and 1.13 from 1997 - 2000, respectively. While the percentage of monotherapy increased from 63.6% in 1997 to 75.5% in 2000, the combination therapies did not experience a rapid and sustained growth. Among the combination therapies, PPI + amoxicillin + metronidazole and PPI + amoxicillin were popular in 1997 and 1998, but triple therapy with PPI + amoxicillin + clarithromycin predominated in 1999 and 2000.

CONCLUSIONS

Despite increasing use, prescribing volumes of PPIs in Taiwan were far fewer than those in other developed countries. Treatment of Helicobacter pylori-related disorders in Taiwan followed universal standard.

Preparation and release characteristics of polymer-coated and blended alginate microspheres

To prevent a rapid drug release from alginate microspheres in simulated intestinal media, alginate microspheres were coated or blended with polymers. Three polymers were selected and evaluated such as HPMC, Eudragit RS 30D and chitosan, as both coating materials and additive polymers for controlling the drug release. This study focused on the release characteristics of polymer-coated and blended alginate microspheres, varying the type of polymer and its concentration. The alginate microspheres were prepared by dropping the mixture of drug and sodium alginate into CaCl(2) solution using a spray-gun. Polymer-coated microspheres were prepared by adding alginate microspheres into polymer solution with mild stirring. Polymer-blended microspheres were prepared by dropping the mixture of drug, sodium alginate and additive polymer with plasticizer into CaCl(2) solution. In vitro release test was carried out to investigate the release profiles in 500 ml of phosphate buffered saline (PBS, pH 7.4). As the amount of polymer in sodium alginate or coating solution increase, the drug release generally decreased. HPMC-blended microspheres swelled but withstood the disintegration, showing an ideal linear release profiles. Chitosan-coated microspheres showed smooth and round surface and extended the release of drug. In comparison with chitosan-coated microspheres, HPMC-blended alginate microspheres can be easily made and used for controlled drug delivery systems due to convenient process and controlled drug release.

A case of mitochondrial trifunctional protein deficiency diagnosed by acylcarnitine profile and DNA analysis in a dried blood spot of a 4-day-old boy

We report a Korean case, consistent with a biochemical diagnosis of trifunctional protein (TFP) deficiency, in which molecular diagnosis revealed a novel mutation in the alpha-subunit of TFP and the rare combination of two intergenic region (C/C and G/G) polymorphisms.

Preparation and characterization of chitosan microparticles intended for controlled drug delivery

Chitosan microparticles were prepared with tripolyphosphate (TPP) by ionic crosslinking. The particle sizes of TPP-chitosan microparticles were in range from 500 to 710 microm and encapsulation efficiencies of drug were more than 90%. The morphologies of TPP-chitosan microparticles were examined with scanning electron microscopy. As pH of TPP solution decreased and molecular weight (MW) of chitosan increased, microparticles had more spherical shape and smooth surface. Release behaviors of felodipine as a model drug were affected by various preparation processes. Chitosan microparticles prepared with lower pH or higher concentration of TPP solution resulted in slower felodipine release from microparticles. With decreasing MW and concentration of chitosan solution, release behavior was increased. The release of drug from TPP-chitosan microparticles decreased when cross-linking time increased. These results indicate that TPP-chitosan microparticles may become a potential delivery system to control the release of drug.

Preparation and characterization of drug-loaded polymethacrylate microspheres by an emulsion solvent evaporation method

Microspheres containing the anti-hypertension drug, felodipine, were prepared by the emulsion solvent evaporation method (o/o) using acrylate methacrylate copolymers, Eudragit RL PO and Eudragit RS PO, as wall materials. In order to increase the encapsulation efficiency, a mixed solvent system comprising 1:1 proportions of acetonitrile and dichloromethane was used as a dispersed phase. The morphology of the microspheres was evaluated using a scanning electron microscope, which showed a spherical shape with smooth surface. The mean sphere diameter was between 9.5-13.2 microm and the microencapsulation efficiencies ranged from 51.4-80.4%. The release profiles and encapsulation efficiencies depended strongly on the structure of the polymers used as wall materials. The release rate of the Eudragit RS PO microspheres was much lower than that of Eudragit RL PO microspheres. Whereas Eudragit RL PO microspheres followed the Higuchi rule, Eudragit RS PO microspheres exhibited a triphasic release profile. It is concluded that drug release rate can be controlled by choice of polymer type.

Preparation of alginate beads for floating drug delivery system: effects of CO(2) gas-forming agents

Floating beads were prepared from a sodium alginate solution containing CaCO(3) or NaHCO(3) as gas-forming agents. The solution was dropped to 1% CaCl(2) solution containing 10% acetic acid for CO(2) gas and gel formation. The effects of gas-forming agents on bead size and floating properties were investigated. As gas-forming agents increased, the size and floating properties increased. Bead porosity and volume average pore size, as well as the surface and cross-sectional morphology of the beads were examined with Mercury porosimetry and Scanning Electron Microscopy. NaHCO(3) significantly increased porosity and pore diameter than CaCO(3). Incorporation of CaCO(3) into alginate solution resulted in smoother beads than those produced with NaHCO(3). Gel strength analysis indicated that bead strength decreased with increasing gas-forming agent from 9 to 4 N. Beads incorporating CaCO(3) exhibited significantly increased gel strength over control and NaHCO(3)-containing samples. Release characteristics of riboflavin as a model drug were studied in vitro. Release rate of riboflavin increased proportionally with addition of NaHCO(3). However, increasing weight ratios of CaCO(3) did not appreciably accelerate drug release. The results of these studies indicate that CaCO(3) is superior to NaHCO(3) as a gas forming agent in alginate bead preparations. The enhanced buoyancy and sustained release properties of CaCO(3)-containing beads make them an excellent candidate for floating drug dosage systems (FDDS).

Evaluation of acupuncture effect to chronic myofascial pain syndrome in the cervical and upper back regions by the concept of Meridians

Myofascial pain syndrome (MPS) in the cervical and upper back regions is a common medical problem. The involved muscles include trapezius, multifidi, splenius cervicis, levator scapulae, supraspinatus or infraspinatus. Acupuncture is a well-known method for relief of chronic pain. In this study, we evaluated the effect of acupuncture in MPS and its durability by using the concept of meridians. Twenty-nine patients with chronic MPS in the upper back and cervical regions received acupuncture 2 times per week for 3 weeks. According to the pathways of the meridians, we chose acupuncture points by the pain regions located in which parts of meridian passing (i.e. "Where the meridian passes, where to treat the disease."). We evaluated the intensity of pain by visual analog scales (VAS) and active range of motion (ROM) of neck before and after therapy. After receiving acupuncture for 3 weeks, VAS of pain fell significantly from 9.0+/-1.0 to 4.9+/-2.5 and active ROM of neck significantly increased from 35.8+/-10.2 degrees to 61.3+/-9.4 degrees (p<0.05). The onset of symptom relief was gradual and duration of symptom relief after a course of acupuncture was average 5.3+/-1.2 days. In conclusion, acupuncture is a somewhat effective method for pain relief of patients with chronic MPS in the cervical and upper back regions. However, the effect of acupuncture with the concept of meridians on MPS is insidious and the duration of the relief is not long enough.

Edema due to protein-losing enteropathy--a disorder rarely considered by nephrologists

In the differential diagnosis, protein-losing enteropathy (PLE) is a rarely considered explanation of edema. Three such cases are reported in this article. Clinical presentations varied from severe generalized anasarca and respiratory distress to mild pitting edema on the pretibial surface. Hypoalbuminemia (< 35 g/l) was another common finding in addition to edema. The patients were carefully examined to exclude other causes of hypoalbuminemia. Two patients experienced diarrhea. Endoscopic studies (plus biopsies) for any mucosal lesion in the stomach and colon were also performed. PLE was confirmed by the positive radionuclide scanning results after infusing intravenous 99mTc human serum albumin (USA). Investigation for the etiologies showed intestinal lymphangiectasia in 1 patient, Menetrier's disease in another, and no recognizable cause in the third. The severe anasarca of the patient with intestinal lymphangiectasia didn't respond to corticosteroids and albumin supplement plus large doses of furosemide. She died of overwhelming pulmonary infection despite the use of powerful antibiotics (ceftriaxone and amikacin). We planned to treat the Menetrier's disease patient with somatostatin to decrease the exocrine activities of the intestinal tract. The patient with presumable idiopathic PLE had the least severe edema and was not treated with any medication. In addition to the above patients, another 3 patients with hypoalbuminemia and edema were also noted to have positive HSA scan results. However, 2 of these patients had systemic lupus erythromatosus and the third pulmonary tuberculosis and biopsy-proven membranous nephropathy. Treatment of their underlying diseases showed satisfactory remission of edema.

A giant pyogenic granuloma in the nasal cavity caused by nasal packing

Pyogenic granuloma is a benign, rapidly growing hemorrhagic lesion of unknown origin. This disorder, however, is obscure to many rhinologists, because the nose is a relatively rare location for the lesion. In the practice of otorhinolaryngology, nasal packing is a very common procedure for nasal bleeding and postoperative hemostasis. However, few pyogenic granulomas occurring from nasal packing have been reported in the literature. A 56-year-old man underwent nasal packing with vaseline gauze because of nasal bleeding. Two months later, a dark brown nasal tumor was found in his nasal cavity. He underwent endoscopic endonasal removal of the tumor. The pathology result showed a pyogenic granuloma. This is the third case recorded in the literature of a confirmed pyogenic granuloma occuring as a complication of nasal packing. This uncommon lesion should be considered in the differential diagnosis of a rapidly growing hemorrhagic lesion within the nasal fossa.

Leukopenia and thrombocytopenia in hemodialysis patients with hepatitis B or C virus infection and non-hemodialysis patients with hepatitis cirrhosis

AIMS

To investigate the relation of leukopenia and thrombocytopenia in hemodialysis (HD) patients with hepatitis C virus (HCV) infection.

MATERIALS AND METHODS

The study included 86 HD patients with hepatitis B surface antigen-negative and hepatitis C antibody-negative, 28 HD patients with hepatitis C antibody-positive, 22 HD patients with hepatitis B surface antigen-positive, 78 non-HD patients with hepatitis B-induced liver cirrhosis and 38 non-hemodialysis patients with hepatitis C-induced liver cirrhosis. The following parameters were checked: anti-HCV, hepatitis B surface antigen, hemoglobin, hematocrit, white blood cells, platelets, calcium, phosphate, iron, ferritin, albumin, globulin, aspartate transaminase (AST), alanine transaminase (ALT) and C-reactive protein. The history of blood transfusions, medications, erythropoietin doses and adequate dialysis (KTNV) for 6 consecutive months was also recorded from charts.

RESULTS

The HD patients with positive serum anti-HCV and non-HD patients with hepatitis B- or C-induced liver cirrhosis had higher prevalences of leukopenia (39.3%, 43.6% and 50% vs. 15.1%; p < 0.001) and thrombocytopenia (67.9%, 89.7% and 81.6% vs. 34.9%: p < 0.001) than HD patients with serum anti-HCV(-)HbsAg(-). The WBC (4,432 +/- 1,394, 4,792 +/- 2,263 and 4,624 2,446 vs. 5,590 +/- 1,500/mm3; p < 0.001) and platelet counts (140 +/- 45, 80 +/- 50 and 89 +/- 65 vs. 186 +/- 62 x 10(3)/mm3; p < 0.001) of HD patients with positive serum anti-HCV and non-HD patients with hepatitis B- or C-induced cirrhosis were also lower than HD patients without anti-HCV antibody. The liver cirrhosis patients had more thrombocytopenia than the HD patients with anti-HCV(+). The WBC and platelet counts did not vary between HD patients with HbsAg(+) and HD patients with anti-HCV(-)HBsAg(-). The durations of HD, hepatitis and liver cirrhosis were not related to the leukopenia or thrombocytopenia (p > 0.05).

CONCLUSIONS

HCV infection associated with leukopenia and/or thrombocytopenia in HD patients is as common as in non-HD patients with liver cirrhosis. This may be due to the direct effect of hemopoiesis rather than the hyperspleenism of liver cirrhosis patients. There is a need for further prospective investigation to ascertain the clinical significance of leukopenia and thrombocytopenia in HD patients with anti-HCV(+). The prevalence of leukopenia and thrombocytopenia was higher in HD patients with hepatitis C than in HD patients with hepatitis B and HD patient without hepatitis.

Hepatitis C viral genotype influences the clinical outcome of patients with acute posttransfusion hepatitis C

Most patients with an acute infection of hepatitis C virus (HCV) will develop chronic hepatitis, and only about 15-20% of the cases will resolve spontaneously. The mechanism for the different outcomes in patients with acute HCV infection remains unclear. HCV genotype has been recognized as an important factor affecting the clinical course and outcome of chronic hepatitis C patients. In order to evaluate the role of HCV genotype in the clinical course and outcome of acute posttransfusion hepatitis C, 67 patients with acute posttransfusion hepatitis C from a prospective study of posttransfusion non-A, non-B hepatitis were enrolled. Thirty-nine patients (58.2%) were HCV genotype 1b. Among the 67 patients with acute posttransfusion hepatitis C, 53 (79.1%) progressed to chronic hepatitis. Significantly more patients with genotype 1b than non-1b genotypes developed chronic hepatitis (89.7% vs. 64.3%; P = 0.019). There was no significant difference in gender, mean age, amount of transfused blood, hepatitis symptoms, jaundice, incubation period, peak serum alanine transaminase, or serum HCV RNA titer between patients with HCV genotype 1b and non-1b infections. Patients who developed chronic hepatitis had a significantly greater incidence of genotype 1b infection (66.0% vs. 28.6%; P = 0.013) and a longer incubation period (7.3 weeks vs. 5.4 weeks; P = 0.052) than patients whose infection was resolved. Patients with a genotype 1b infection that resolved itself spontaneously all had an incubation period of less than 6 weeks. Multivariate logistic regression analysis revealed that genotype 1b and an incubation period > or = 6 weeks were significant predictive factors for the development of chronic hepatitis. Therefore, the HCV genotype can influence the outcome of patients with acute HCV infection.

Hepatitis C virus infection: an overview

Hepatitis C virus is an RNA virus belonging to the Flaviviridae family. The diagnosis of hepatitis C virus infection was based on the detection of serum antibody to hepatitis C virus (anti-HCV) using immunoassay or recombinant immunoblot assay, or the direct detection of serum hepatitis C virus RNA using polymerase chain reaction. The anti-HCV positive rate in the general population or healthy blood donors is 0.5% to 4% worldwide. Parenteral transmission was the major route of hepatitis C virus infection. High-risk groups for hepatitis C virus infection included recipients of blood transfusion of which the blood donors were not screened for anti-HCV, intravenous drug abusers, hemophiliacs, and patients who have received hemodialysis. More than 80% of patients with hepatitis C virus infection progressed into chronicity, 20% to 30% of patients with chronic hepatitis C progressed to cirrhosis after 10 to 20 years of follow-up, and some developed hepatocellular carcinoma. Hepatitis C virus was the most common cause of chronic hepatitis, cirrhosis, and hepatocellular carcinoma in Western countries and in Japan, where hepatitis B virus is not endemic. Interferon therapy at a dosage of 3 MU and subcutaneous injection 3 times per week for 6 months normalized serum transaminase in 50% of patients with chronic hepatitis C at the end of treatment. However, the relapse rate was high and only 20% to 25% of patients sustained response 1 year after discontinuing therapy. Prolonged interferon therapy up to 12 to 18 months has been suggested to improve interferon efficacy by decreasing the relapse rate and thus increasing the sustained response rate. New interferon preparation such as consensus interferon and long-acting pegylated-interferon has recently shown better treatment response than the traditional interferon regimen. The combined regimen of interferon and ribavirin was shown to have better efficacy than interferon alone in treating patients with chronic hepatitis C.

Colorectal cancer in patients 20 years old or less in Taiwan

BACKGROUND

Colorectal cancer (CRC) is predominantly a disease of the elderly population, but it sometimes occurs in young patients. The diagnosis of CRC in youngsters is often overlooked by physicians or presentation may be delayed.

METHODS

With assistance from the cancer registry center of Taipei Veterans General Hospital, we collected data on all types of colorectal malignancy, including carcinoma, adenocarcinoma, or lymphoma in patients aged 20 or younger. All available medical charts and pathologic specimens were reviewed in detail.

RESULTS

A total of 28 cases were analyzed. The leading presenting symptom was abdominal pain (92%). The locations of the primary tumors were evenly distributed, and the major histologic type was predominantly adenocarcinoma. However, the proportion of mucinous adenocarcinoma was higher than that in the older population. Most of the cases were advanced (11 tumors were classified as Dukes stage C and another 11 as Dukes stage D). The overall 5-year survival rate was 21%.

CONCLUSIONS

Despite the rarity of CRC during the first two decades of life, physicians need to be aware of the possibility and to evaluate suggestive signs and symptoms by colonoscopy or barium enema. Family history of CRC, inflammatory bowel disease, previous polyps, or familial polyposis did not play a crucial role in this group of young patients.

The impact of diabetes on economic costs in dialysis patients: experiences in Taiwan

Diabetes mellitus carries a great burden on healthcare costs due to its growing population and high co-morbidity. This adverse effect sustains even when patients develop end-stage renal disease (ESRD). We here present data showing the effect of diabetes on economic costs in dialysis therapy in Taiwan. As of the end of 1997, we have 22,027 ESRD patients with a prevalence and incidence rate of 1013 and 253 per million populations, respectively. Diabetic nephropathy is the second most common cause of the underlying renal diseases, but accounts for 24.8% of the prevalent patients and 35.9% of the incident cases. The diabetic patients engendered 11.8% more expense for care of dialysis than the non-diabetic patients (US $26,988 vs. US $24,146 per patient-year). Higher inpatient cost mainly account for the difference. As compared to non-diabetic patients, the diabetic patients had 3.5 times more inpatients costs (US $1325 vs. US $4677 per patient-year), and higher proportion of inpatient-to-annualized cost ratio (5.5 vs. 17.3%) resulting from their more frequent hospitalization (0.59 vs. 1.13 times per patient-year) and longer hospital stay (6.7 vs. 18.9 days per patient-year). The major causes responsible for a more frequent hospitalization were cardiovascular disease, poorly controlled hyperglycemia, sepsis and failure of vascular access. The annualized costs for care of dialysis patients in Taiwan, including inpatient and outpatient costs, averaged US $25,576 per patient-year. This value is approximately half of that in most of the western countries and Japan. Thus, a more cost-effective way to achieve savings is to reduce the high incidence rate of dialysis population and to maximize the quality of dialysis treatment for avoiding hospitalization. Recent studies had shown that tight blood pressure control, intensive glycemic control, and use of angiotensin converting enzyme inhibitors in diabetic patients significantly reduced not only the rate of progressive renal failure, but also substantially reduced the cost of complications and led to higher cost effectiveness. Once diabetic patients reach stage of ESRD, an optimized pre-ESRD care and consideration of kidney transplantation are essential in terms of better patient survival and cost savings.

Kainate receptors in primary afferents to the rat gracile nucleus

In a previous work, we demonstrated that under weak paraformaldehyde fixation, kainate receptors (KR) (GluR5/6/7) are expressed in primary afferent terminals in superficial dorsal horn. We extended our study to primary afferents to the gracile nucleus; immunostaining for GluR5/6/7 in weakly fixed sections was in puncta of variable size. In double-stained sections, the majority of immunostained puncta colocalized with synaptophysin. Because of their large size and relations with smaller puncta, single-stained for synaptophysin, these terminals were presumed to be of dorsal column primary afferents. This was confirmed by anterograde labeling with cholera toxin B and with electron microscopy, which showed that GluR5/6/7 was present in terminals with morphology of primary afferents. These observations demonstrate that expression of presynaptic KR is a general feature of primary afferents with different functional properties.

Concomitant prescription of non-steroidal anti-inflammatory drugs and antacids in the outpatient setting of a medical center in taiwan: a prescription database study

OBJECTIVE

Although antacids were ineffective in preventing serious gastrointestinal complications caused by non-steroidal anti-inflammatory drugs (NSAIDs), many physicians in Taiwan still prescribe antacids concomitantly with NSAIDs. A survey of an outpatient prescription database was performed to measure the extent of such a combination and to explore its associated factors.

METHODS

One month of the outpatient prescription data in the polyclinic of a medical center in Taiwan served to estimate the frequency of concomitant antacid prescription with NSAIDs. The age of patients, duration of NSAID prescriptions, concomitant prescription of corticosteroid or ulcer-healing drugs, and inter-departmental variations were compared between the NSAID prescriptions with and without antacids.

RESULTS

Antacids were present in 87.3% of prescriptions with NSAIDs but only in 34.4% of prescriptions without NSAIDs (P<0.001). The prescription of antacids was significantly associated with the prescription of NSAIDs. The age of patients and duration of NSAID prescriptions did not influence the co-prescription of NSAIDs and antacids. Significant inter-departmental variations were noted in which the surgeons and orthopedic doctors tended to co-prescribe antacids with NSAIDs more often than the internists.

CONCLUSION

The physicians in Taiwan tended to prescribe NSAIDs together with antacids. The rationality of this co-prescription deserves further investigation.

Two cases of primary malignant melanoma of the lacrimal sac

BACKGROUND

Malignancy of the lacrimal sac is rare, and primary malignant melanoma in this region is extremely rare.

METHODS

We report two cases of malignant melanoma of the lacrimal sac presented with epiphora and a palpable mass in the medial canthal area. We performed radical surgery and radiation therapy.

RESULTS

The light microscopic, immunohistochemical, and electron microscopic studies confirmed the diagnosis. One of the patients, a 65-year-old-woman, has no evidence of recurrence or distant metastasis 3 years after surgery and radiotherapy, whereas another patient, a 56-year-old man, died of distant metastasis 6 months after surgery and radiotherapy.

CONCLUSIONS

We present two cases of malignant melanoma of the lacrimal sac that masqueraded as chronic dacryocystitis. Head and neck surgeons should be aware of this disease entity when encountered with patients with epiphora and mass in the medial canthal area.

Inadvertent hypothermia causes pulseless electrical activity in a patient during cervical spine surgery--a case report

Recent studies have shown that hypothermia triples the incidence of major cardiac events. We present a happening in which a 71-year-old patient developed pulseless electrical activity (PEA) while he was undergoing cervical laminectomy for spinal stenosis in the sitting position. Thromboembolism or venous air embolism and acute myocardial infarction were respectively excluded by transesophageal echocardiography and cardiac enzymes analysis to be the causes of the cardiac event. The abnormal finding that stood out was low nasopharyngeal temperature (31 degrees C) during the procedure, which was thought to contribute to the development of the PEA episode.

Evaluation of survival rate after follicular unit transplantation using the KNU implanter

BACKGROUND

Many hair transplant surgeons have advocated the use of micrograft megasessions for the purpose of a more natural looking end result, especially in the Oriental with higher skin/hair color contrast and darker, coarse, straight hairs. But it also has some fundamental limitations. Most important are a low graft yield and a low density after transplantation. There are several reports about the survival rate of micrografts in Caucasians, though the results are variable, but few reports about the survival rate and fate of micrografts in Orientals.

OBJECTIVE

To compare the survival rate of one-hair follicular units with that of two-hair follicular units using the KNU implanter, to ascertain the average survival rate of micrografts (one- and two-hair follicular units), and to evaluate the fate of grafted hair according to time.

METHODS

Two templates of 1.5 cm2 were made by tattooing on both sides of the frontoparietal recess areas in 11 patients with male pattern baldness (beyond Norwood type IIIa). The authors planted one-hair unit micrografts in the left template and two-hair unit micrografts in the right template, which were prepared by the concept of follicular unit, and counted the surviving number of follicular units at 1 and 3 months and total hairs at 6 and 12 months after transplantation.

RESULTS

The mean survival rate by the number of follicular units was 47.3 and 57.4% at 1 and 3 months after transplantation, respectively. The mean survival rate by the total number of hairs was 92.0 and 90.4% at 6 and 12 months after transplantation, respectively.

CONCLUSION

About 50% of the transplanted hairs fell out in 1 month, but at 6 months the survival rate of follicular unit transplantation using the KNU implanter showed a good result (92%), and there were no significant differences in the mean survival rate of follicular unit and total hairs between one-hair and two-hair units at 1, 3, 6, and 12 months after transplantation.

Presynaptic kainate receptors in primary afferents to the superficial laminae of the rat spinal cord

Subunits of glutamate receptors participate in the regulation of sensory transmission at primary afferent synapses in the superficial laminae of dorsal horn (DH). We report here on the distribution of kainate receptors (GluR5/6/7) in these laminae by using light microscope (LM) and electron microscope (EM) immunocytochemistry. Standard (4%) paraformaldehyde fixation resulted in immunostaining for GluR5/6/7 in perikarya and fine processes in lamina II, especially its inner part (IIi). Preembedding EM revealed immunostaining of dendrites, perikarya, and occasional terminals, presumed to be from primary afferent fibers, at the center of glomerular arrangements. In rats perfused with 0.5% paraformaldehyde, LM showed a more punctate staining, mainly in the ventral part of lamina IIi and lamina III, than in material fixed with 4% paraformaldehyde. Approximately two-thirds of GluR5/6/7 puncta were also immunostained with synaptophysin, suggesting that in material fixed with 0.5% paraformaldehyde, a large fraction of these are synaptic terminals. Double immunostained puncta disappear 4 days after dorsal rhizotomy, suggesting that most of GluR5/6/7-immunopositive terminals are from primary afferent fibers. EM material fixed with 0.5% paraformaldehyde confirmed the expression of GluR5/6/7 in numerous synaptic endings with morphology of primary afferents. To determine the type of primary afferent terminals that express GluR5/6/7, two neuroanatomic tracers were injected in the sciatic nerves. The lectin from Bandeiraea simplicifolia (IB4) is selectively taken up by unmyelinated primary afferent fibers that terminate in the outer part of lamina II (IIo) and dorsal part of lamina IIi, whereas the B subunit of the cholera toxin (CTB) is selectively taken up by a broader class of primary afferents which, in superficial DH, terminate mainly in laminae I, ventral part of IIi, and III. Approximately 20% of GluR5/6/7-immunoreactive puncta colocalized with IB4, whereas approximately 40% of GluR5/6/7-immunoreactive puncta colocalized with CTB. The present study shows that (1) GluR5/6/7 does not have a clear and consistent spatial relation with postsynaptic sites, (2) a large number of primary afferents express GluR5/6/7, and (3) these are not limited to one functional class. Thus, modulation by glutamate of primary afferent terminals by means of kainate receptors in the superficial laminae of DH may predominantly involve presynaptic mechanisms.

Palladin is expressed preferentially in excitatory terminals in the rat central nervous system

Palladin is a recently described intracellular protein associated with the actin cytoskeleton and cell adhesion in fibroblasts. In Western and Northern blot analyses, palladin expression is ubiquitous in embryonic mice, but it is down-regulated dramatically in most adult tissues. Significant amounts of palladin persist in the brain of adult rodents, as assessed by Western blot analysis. With this work, we extend preliminary observations and determine the overall distribution and subcellular location of palladin throughout the rat brain. In sagittal and coronal sections of the central nervous system, immunostain for palladin is present throughout the brain and spinal cord, but not uniformly. The densest regions of immunostain include the olfactory bulb, cerebral and cerebellar cortex, hippocampus, amygdala, superior colliculus, and superficial laminae of the spinal dorsal horn. Because immunostain characteristically is punctate, we performed double staining for palladin and the presynaptic marker synaptophysin. Confocal microscopy showed that palladin-immunopositive puncta are also immunopositive for synaptophysin; the proportion of synaptophysin-immunopositive puncta that also stained for palladin ranged from 100% of mossy fiber terminals in field CA3 of the hippocampus and in the cerebellar cortex to 60--70% of terminals in the cerebral cortex, striatum, and spinal dorsal horn. The presence of palladin in synaptic terminals was confirmed by electron microscopy. Because immunostained terminals commonly establish asymmetric synapses, the selectivity of palladin expression in synaptic terminals was tested by double staining for palladin and gamma-aminobutyric acid. The modest level of colocalization in this material at both the light microscopic and electron microscopic levels suggests a selectivity of palladin for terminals that release excitatory neurotransmitters. As concomitant work in cell cultures has shown that palladin participates in axonal development and migration, the present results suggest that palladin persists at excitatory synapses of the adult nervous system.

Vanilloid receptor VR1 is both presynaptic and postsynaptic in the superficial laminae of the rat dorsal horn

Terminals in the rat spinal cord that express the vanilloid receptor VR1 are from small and medium dorsal root ganglion (DRG) neurons and appear prominent in lamina I and inner lamina II. Because primary afferents from these neurons can be myelinated or unmyelinated and their terminals in these laminae can be of various morphological and functional types, we undertook this study to identify the type(s) of VR1-positive afferent fibers and terminals. In the DRG, many small and medium-sized neurons are immunopositive. Under electron microscopy, dorsal root afferents that are immunopositive for VR1 are predominantly unmyelinated. Large numbers of VR1-positive terminals in lamina I are of the nonglomerular type and may contain dense core vesicles. VR1 immunoreactivity in terminals in lamina I is in good agreement with data on noxious, heat-sensitive neurons in the dorsal horn. Two types of glomerular afferent terminals in lamina II also are immunopositive for VR1. In both laminae, most VR1-positive terminals are distinct from substance P-positive terminals. However, the immunoreactivity in lamina II also is prominent in dendrites that are contacted by primary afferent endings. Because we also observed patchy immunostaining in cell bodies in lamina II, this unexpected result may reflect synthesis of VR1 by neurons in this lamina. However, because dorsal rhizotomy abolishes VR1 staining in both laminae I and II, it is suggested that the expression and intracellular dynamics of VR1 in lamina II neurons are controlled by presynaptic input.

Tuberculosis in maintenance dialysis patients

In this investigation, we tried to find the incidence and characteristics of tuberculosis (TB) in dialysis patients previously found only in a small number of cases. We collected the cases of newly diagnosed TB patients in Taiwan during 1997. Simultaneously, all dialysis patients were collected and matched with the TB cases to identify the dialysis patients who had also contracted TB. The annual incidence of the dialysis population was 493.4/100,000, 6.9 times that of the general population (71.1/100,000). The annual incidence for the male dialysis population was 573.3, the incidence was 479.2 for the female dialysis population. The incidence for the general population was 97.1 and 43.7/100,000, respectively. Although the 1-year mortality rate due to TB (1.7 vs. 1.9%, p > 0.05) was similar in both populations, the non-TB mortality was much higher in the dialysis population than that in the general population (25.6 vs. 11.1%, p < 0.05). Finally, the 1-year mortality rate of dialysis patients with TB is 3.3 times higher than that in dialysis patients without TB (27.3 vs. 8.3%, p < 0.05). The findings suggest that uremia modifies the behavior of TB, jeopardizes female and younger dialysis patients, poses a higher risk of extrapulmonary dissemination, and predicts a higher overall mortality.

Clinical, virological, and pathological significance of hepatic bile duct injuries in Chinese patients with chronic hepatitis C

PURPOSE

Hepatic bile duct injuries are characteristic histological findings in patients with chronic hepatitis C virus (HCV) infection. However, the pathogenesis and clinical significance of this phenomenon remain unclear. The aims of this study were to evaluate the prevalence and clinical significance of hepatic bile duct injuries in Chinese patients with chronic hepatitis C.

METHODS

One hundred and seventeen Chinese patients with chronic hepatitis C were enrolled. Clinical, biochemical, immunological (serum autoantibodies and cryoglobulinemia), histological, and virological data (serum HCV RNA titer and HCV genotype) were compared between patients with and without hepatic bile duct injuries.

RESULTS

Eighty-three (71%) of the 117 patients with chronic hepatitis C had hepatic bile duct injuries. Patients with hepatic bile duct injuries had a significantly higher frequency of HCV genotype 1b; a higher mean serum globulin level; significantly higher mean scores for histological periportal necro-inflammation, portal inflammation, and fibrosis; and more severe portal lymphoid aggregation/follicles when compared with patients without hepatic bile duct injuries (P < 0.05, all). No significant differences in the presence of serum autoantibodies, cryoglobulinemia, mean serum HCV RNA titer, or response to interferon treatment were noted between the two groups. Multivariate logistic regression analysis showed that HCV genotype 1b infection, portal inflammation, and lymphoid aggregation/follicles were significant independent predictors associated with hepatic bile duct injuries.

CONCLUSIONS

The presence of hepatic bile duct injuries in Chinese patients with chronic hepatitis C was significantly correlated with HCV genotype 1b infection, and the patients with these injuries had more severe portal inflammation and formation of lymphoid aggregates/follicles.

Studies of the synthesis of SSZ-25 zeolite in a "mixed-template" system

The synthesis of aluminosilicate zeolite, SSZ-25, is described using a two-component organic guest molecule strategy. This method has been recently described by us and is quite effective in crystallizing a variety of aluminosilicate zeolites with reduction in template cost. In this instance the original organic guest component used in the discovery of SSZ-25, N',N',N'-trimethyl-2-adamantammonium cation, is used in conjunction with a variety of smaller amines. The amine is the major organic component in the synthesis and the quaternary ammonium compound, while a minor component, is essential for structure direction to the desired zeolite product. Studies here show that the adamantyl component is preferentially taken up during crystal growth. Our studies showed that the use of the multi-organic component approach to synthesis resulted in a faster and cheaper route to crystallizing SSZ-25. The SSZ-25 has been described in the literature as having the MWW topology and as such has two different channel systems accessed by 10-ring openings; the channel systems do not intersect. One set of 10-rings open into large cavities. In this study we used NMR spectroscopy to examine the as-made materials and to see if the two organic components are used in different capacities in the synthesis, probing if the admantyl component is only found in these larger cavities. The crystalline products could be affected by solvent extraction with polar solvents like dimethylformamide: the X-ray powder patterns and elemental analyses changed with solvent treatment. The solvent-treated crystals were studied by NMR spectroscopy, elemental analysis, and argon adsorption. The two-component organic guest approach was also found to be quite flexible not only with regard to the amine, but also towards the quaternary ammonium compounds. Non-adamantyl polycyclic templates could be used, and polar but non-quaternized adamantyl derivatives also succeeded in directing towards SSZ-25 formation. On the other hand. in one instance it was shown that the two-component approach favors SSZ-25 as the kinetic product but at longer run times Ostwald ripening was observed, leading to the disappearance of SSZ-25 and formation of ferrierite zeolite and quartz.

cDNA sequence and gene expression of storage protein-2--a juvenile hormone-suppressible hexamerin from the fall webworm, Hyphantria cunea Drury

We isolated and sequenced a cDNA clone corresponding to storage protein-2 (SP-2) from the fall webworm, Hyphantria cunea. The cDNA for SP-2 (2572 bp) codes for a 747-residue protein with a predicted molecular mass of 88.5 kDa. The calculated isoelectric point is 7.6. Multiple alignment analysis of amino acid sequence revealed that SP-2 is most similar to BJHSP2 (74.3% identity). According to both the phylogenetic analyses and criteria for amino acid composition, SP-2 belongs to the subfamily of moderately methionine-rich storage proteins (3.2% methionine, 11.8% aromatic amino acid). Topical application of the JH analog, methoprene, after head ligation of larvae, suppressed transcription of the SP-2 gene, indicating hormonal effects at the transcriptional level. The SP-2 transcript was detected by Northern blot analysis in Malpighian tubules, in addition to the fat body where it was most abundant. The local expression of SP-2 in Malpighian tubules suggests that it may have some function in that organ.

Expression of human beta-defensin 1 mRNA in human palatine tonsil

Defensins are a newly delineated family of effector molecules whose contribution to host defense, inflammation and cytotoxicity may be considerable for humans. Beta-defensins are cationic peptides with broad-spectrum antimicrobial activity that are produced by epithelia at the mucosal surface. Tonsillar epithelium, which is constantly exposed to microorganisms, may express these natural antibiotic peptides as part of its protective function. In this study we searched for the expression of hBD-1 mRNA in palatine tonsillar epithelium without signs of infection, using reverse transcriptase-polymerase chain reaction and in situ hybridization. Total RNA was isolated from non-infected tonsil and hBD-1 mRNA was identified in these tissues. From in situ hybridization, the expression of hBD-1 mRNA was seen to be localized in the surface epithelia of palatine tonsil. These data suggest that hBD-1 of the palatine tonsil may also play an important role in innate defense against microorganisms.

Protein-losing enteropathy: diagnosis with (99m)Tc-labeled human serum albumin scintigraphy

PURPOSE

To investigate the diagnostic value of technetium 99m-labeled human serum albumin (HSA) scintigraphy in a group of patients suspected of having protein-losing enteropathy (PLE).

MATERIALS AND METHODS

After intravenous injection of 740 MBq of freshly prepared (99m)Tc HSA, serial images of the abdomen were obtained from 10 minutes until 24 hours after injection. A (99m)Tc HSA scan was considered positive for PLE if there was visible tracer exudation in the gut. The diagnosis was established on the basis of standard clinical and biopsy findings.

RESULTS

Thirty-nine scans were obtained: 27 scans in 26 suspected cases of PLE and 12 scans in control subjects with no known gastrointestinal disease. Twenty-five of the 26 studies in patients suspected of having PLE showed (99m)Tc HSA activity in the bowel. Among the 25 studies with positive findings, seven demonstrated PLE only on images obtained 24 hours after injection. In the control subjects, no activity was seen in the bowel.

CONCLUSION

(99m)Tc HSA with serial scanning for up to 24 hours is reliable and useful for imaging PLE. Sites of protein loss may also be demonstrated. This imaging method is convenient, easy to perform, and yields results within 24 hours.

Tinnitus caused by traumatic posterior auricular artery--internal jugular vein fistula

A patient with an arteriovenous fistula that developed after a traffic accident was recently treated. The patient noticed pulsatile tinnitus in the right orbital region two months after the accident. On the first visit, the preliminary clinical impression of this case was a carotid-cavernous fistula, but angiography showed a fistula between the posterior auricular artery and the internal jugular vein. Although rare, this arteriovenous fistula should be included in the differential diagnosis of pusatile tinnitus in the orbit region. The fistula was controlled by embolization with a platinum coil. This is the first report of an arteriovenous fistula between the posterior auricular artery and internal jugular vein.

Cationic polymers for gene delivery: designs for overcoming barriers to systemic administration

Cationic, polymer-based delivery systems have faced limitations in the systemic delivery of therapeutic gene drugs due to difficulties in formulation, in vivo stabilization, toxicity and low transfection efficiencies. Strategies for overcoming some of these barriers have utilized knowledge gained from the fields of colloidal stabilization and protein trafficking. This review highlights recent efforts in polycation preparations that include the development of new polymers for gene delivery, the modification of traditional polycations with hydrophilic polymers for salt and serum stability and the addition of bioactive functionalities to polymers for enhanced intracellular trafficking. These studies have resulted in polymer/DNA composites with increased stability and delivery efficiencies.

Plasma and urinary endothelin-1 in focal segmental glomerulosclerosis

The kidney is an important site of endothelin-1 (ET-1) production and is particularly susceptible to ET-1 action. Infusion of ET-1 in rats induces both functional and morphological alterations in the kidneys. Increased plasma level of ET-1 has been reported in patients with chronic renal failure. However, there are still no reports on the plasma and urinary ET-1 levels in patients with focal segmental glomerulosclerosis (FSGS). In the present study, we have measured the plasma concentration and urinary excretion rate of ET-1 in 15 patients with nephrotic syndrome due to FSGS, and observed the serial changes of plasma and urinary ET-1 in nephrotic rats with FSGS, induced by repeated injection with puromycin aminonucleoside (PAN). ET-1 was measured with radioimmunoassay. The results showed that plasma ET-1 concentration in FSGS patients was significantly higher than in normal controls (P < 0.05), and that urinary ET-1 excretion rate was also significantly higher in FSGS patients than in normal controls (P < 0.01). In FSGS patients, the plasma and urinary ET-1 was significantly correlated (P < 0.05), and the urinary ET-1 excretion rate was significantly correlated with the amount of proteinuria (P < 0.05) and the glomerular sclerosing score (P < 0.01). In the ten rats with PAN-induced FSGS, serial examination showed a significant increase in plasma ET-1 after 8 weeks of injections, while the urinary ET-1 excretion rate showed a biphasic increase that showed a peak after 4 to 6 weeks. The same changes in plasma and urinary ET-1 levels were not observed in control rats injected with normal saline at the same frequency. Our results suggest that ET-1 may be involved in the pathogenesis of FSGS in both humans and rats.

Possibility of reciprocal infection of methicillin-resistant Staphylococcus aureus between medical personnel and patients undergoing middle ear surgery

The incidence of methicillin-resistant Staphylococcus aureus (MRSA) infection after middle ear surgery has recently increased in our hospital. In this study we tried to determine whether the strains of MRSA isolated from infected patients are identical to those obtained from medical personnel, to prove a reciprocal transmission between medical personnel and patients. Surveillance bacterial cultures of medical personnel were performed from the anterior nares and from the fingertip. Molecular epidemiological studies, ribotyping and pulsed-field gel electrophoresis (PFGE) were used to compare the 12 MRSA strains obtained from carriers among medical personnel with the 60 strains identified from patient's otorrhea. Six different MRSA strains were identified from ribotyping, and three subtypes from PFGE. There was a particular subtype which was the most frequently identified strain found in both medical carriers and patients. Postoperative MRSA infection rates after the treatment of medical carriers and application of preventive procedures decreased from 11.9 to 5.7%. These findings suggest that the MRSA transmissions have occurred between medical personnel and patients.

Effects of structure of beta-cyclodextrin-containing polymers on gene delivery

Linear cationic beta-cyclodextrin-based polymers (betaCDPs) are capable of forming polyplexes with nucleic acids and transfecting cultured cells. The betaCDPs are synthesized by the condensation of a diamino-cyclodextrin monomer A with a diimidate comonomer B. In this paper, the effects of polymer structure on polyplex formation, in vitro transfection efficiency and toxicity are elucidated. By comparison of the betaCDPs to polyamidines lacking cyclodextrins, the inclusion of a cyclodextrin moiety in the comonomer A units reduces the IC50s of the polymer by up to 3 orders of magnitude. The spacing between the cationic amidine groups is also important. Different polymers with 4, 5, 6, 7, 8, and 10 methylene units (betaCDP4, 5, 6, 7, 8, and 10) in the comonomer B molecule are synthesized. Transfection efficiency is dependent on comonomer B length with up to 20-fold difference between polymers. Optimum transfection is achieved with the betaCDP6 polymer. In vitro toxicity varied by 1 order of magnitude and the lowest toxicity is observed with betaCDP8. The LD40 of the betaCDP6 to mice is 200 mg/kg, making this polymer a promising agent for in vivo gene delivery applications.

Clinical, virologic, and pathologic significance of elevated serum alpha-fetoprotein levels in patients with chronic hepatitis C

Elevated serum alpha-fetoprotein (AFP) in patients with chronic hepatitis C is not uncommonly seen, but the pathogenesis of this phenomenon remains unclear. The aims of this study were to assess the prevalence of elevated serum AFP in patients with chronic hepatitis C and to evaluate the clinical, virologic, and histopathologic significance of this phenomenon. One hundred and fifteen Chinese patients with a histologic diagnosis of chronic hepatitis C were enrolled. None had evidence of hepatocellular carcinoma by image study at enrollment and for at least 2 years' follow-up. Of the 115 patients, 33 (29%) had elevated serum AFP (more than 12 ng/mL). There was a significantly lower mean serum albumin (4.0 +/- 0.1 vs. 4.3 +/- 0.1 gm/dL, p <0.001) and higher mean scores for periportal necroinflammation (3.3 +/- 0.3 vs. 2.3 +/- 0.2, p = 0.007) and fibrosis (2.3 +/- 0.2 vs. 1.1 +/- 0.1, p < 0.001) in patients with elevated serum AFP when compared with patients without elevated serum AFP. Patients with elevated serum AFP had significantly more incidences of genotype 1b infection when compared with patients without elevated serum AFP (77% vs. 51%, p = 0.021). Mean serum hepatitis C virus (HCV) RNA titer showed no significant difference between the two groups. Multivariate logistic regression analysis showed that as serum albumin of less than 4.2 gm/dL, a histology fibrotic score of more than 3, and HCV genotype 1b infection were significantly independent predictors associated with elevated serum AFP. In conclusion, elevated serum AFP levels were significantly correlated with lower serum albumin levels, advanced fibrosis/cirrhosis, and genotype 1b infection in patients with chronic hepatitis C.

High prevalence of selective immunoglobulin A deficiency in peritoneal dialysis patients

We encountered two hemodialysis (HD) patients with recurrent infections and complete immunoglobulin A deficiency (IgAD). To survey the possibility of a similar occurrence in other populations, we conducted the present study. We used nephelometry to examine the levels of immunoglobulins G (IgG), A (IgA), and M (IgM) in 42 continuous ambulatory peritoneal dialysis (CAPD) patients, 246 HD patients, 56 chronic renal failure (CRF) patients, and 250 normal adults. Four CAPD patients (9.5%) and five HD patients (2.0%) were found to be completely IgA deficient (IgA < 6.67 mg/dL). Peritoneal dialysis patients therefore had a significantly higher prevalence of IgAD compared with HD and CRF patients. The underlying diseases leading to dialysis therapy in the IgAD patients varied. Their dialysis durations also varied. The occurrence rate of peritonitis in CAPD patients with IgAD was no higher than in patients without IgAD. The clinical significance of IgAD was focused on mucosal immunity, but the exact prevalence of infection was difficult to define. However, these patients' medical records did suggest more frequent respiratory tract infections and cellulitis events than did the records of patients without IgAD. Two PD patients with IgAD died of pneumonia. Immunodiffusion and indirect ELISA methods were used to detect the presence of auto-antibodies, successfully identifying them in three patients. Further research is needed to study other mechanisms of IgAD.

Hepatic steatosis in chronic hepatitis C virus infection: prevalence and clinical correlation

BACKGROUND AND AIMS

Hepatic steatosis is a histological characteristic in patients with chronic hepatitis C virus (HCV) infection. The aim of this study was to evaluate the prevalence of hepatic steatosis in Chinese patients with chronic hepatitis C, and to look for possible correlation with various histopathological changes and to look for possible correlation with various clinical and pathologic variables.

METHODS

One hundred and six patients were enrolled, and patients with alcoholism or diabetes mellitus were excluded. Clinical, biochemical and virologic data, including HCV genotype and serum HCV-RNA titer and histological findings, were compared between patients with and without hepatic steatosis.

RESULTS

Fifty-five (52%) of the 106 patients with chronic hepatitis C had hepatic steatosis. Patients with hepatic steatosis had significantly higher mean serum levels of triglyceride and gamma-glutamyl transpeptidase, higher body mass index, and a higher incidence of obesity compared with patients without hepatic steatosis. No significant differences in serum HCV-RNA titer and HCV genotype or the response to interferon therapy were noted between the two groups. Histological analysis showed patients with hepatic steatosis had a significantly higher mean fibrotic score than patients without hepatic steatosis (1.9 +/- 1.2 vs 1.3 +/- 1.0; P = 0.016). There were no significant differences in the severity of necroinflammation, the presence of lymphoid aggregation/follicle or bile duct damage between the two groups. Multivariate logistic regression analysis showed that independent predictors associated with hepatic steatosis were obesity or a histology fibrotic score of > or = 2.

CONCLUSION

It was found that 52% of Chinese patients with chronic hepatitis C had hepatic steatosis. Patients with hepatic steatosis were more frequently obese and had more severe hepatic fibrosis.

Comparison of clinical, virologic and pathologic features in patients with acute hepatitis B and C

BACKGROUND AND AIMS

The clinical outcomes of adult-acquired acute infection of hepatitis C virus (HCV) and hepatitis B virus (HBV) are quite different. In order to compare the clinical, biochemical, virologic and pathologic pictures in these two groups of patients, we enrolled 22 adult patients with acute hepatitis C and 16 adult patients with acute hepatitis B, on whom liver biopsies were performed within 3 months of acute onset of the illness.

RESULTS

The results showed that a significantly younger age, a higher ratio of the clinical symptoms of jaundice, nausea, vomiting, and poor appetite, a higher mean serum level of alanine transaminase, aspartate transaminase, and total bilirubin were present in patients with acute hepatitis B patients than in those with acute hepatitis C (P < 0.05). There was a significantly higher degree of periportal inflammation and total necro-inflammatory activity in the acute hepatitis B patients (P = 0.002 and 0.049, respectively). Fifteen (68.2%) of the 22 patients with acute hepatitis C had detectable serum HCV-RNA, but only two (14.3%) of the 14 tested patients with acute hepatitis B had detectable serum HBV-DNA, detected by using the branched DNA signal amplification assay. Eighteen (82%) of the 22 acute hepatitis C patients and none of the 16 acute hepatitis B patients progressed into a chronic hepatitis stage (P < 0.001).

CONCLUSION

The manifestations of mild clinical symptoms, lower mean serum transaminases and bilirubin levels, a lesser degree of histological periportal necroinflammation, and more patients with a high circulatory viral load among the acute hepatitis C patients, may lead to more of that group developing chronicity than patients with acute hepatitis B.

The role of peripheral N-methyl-D-aspartate receptors in Freund's complete adjuvant induced mechanical hyperalgesia in rats

We investigated the role of excitatory amino acid receptors in mechanical hyperalgesia induced by subcutaneous injection of Freund's complete adjuvant (FCA) into the rat hind paw. In normal rats, an intraplantar (i.pl.) injection of L-glutamate, but not of D-glutamate (3 pmol/0.1 ml each) produced a mechanical hyperalgesia in the hind paw with a lowered paw-withdrawal threshold to pressure. In rats that developed mechanical hyperalgesia associated with inflammation in the hind paw following i.pl. injection of FCA (0.15 ml), the injection of N-methyl-D-aspartate (NMDA) receptor antagonist, MK-801 (1 pmol/0.1 ml) into the inflamed paw increased the paw pressure threshold. On the other hand, the injection of non-NMDA receptor antagonist, 6-cyano-7-nitroqiunoxaline-2,3-dione (CNQX, 10 pmol/0.1 ml) into the inflamed paw had no effect on FCA-induced lowering of the paw pressure threshold. The results suggest that NMDA, but not non-NMDA receptors play a substantial role in mediating the development of mechanical hyperalgesia induced in the inflamed paw following i.pl. FCA injection.

Complex interactions between autotrophs in shallow marine and freshwater ecosystems: implications for community responses to nutrient stress

The relative biomass of autotrophs (vascular plants, macroalgae, microphytobenthos, phytoplankton) in shallow aquatic ecosystems is thought to be controlled by nutrient inputs and underwater irradiance. Widely accepted conceptual models indicate that this is the case both in marine and freshwater systems. In this paper we examine four case studies and test whether these models generally apply. We also identify other complex interactions among the autotrophs that may influence ecosystem response to cultural eutrophication. The marine case studies focus on macroalgae and its interactions with sediments and vascular plants. The freshwater case studies focus on interactions between phytoplankton, epiphyton, and benthic microalgae. In Waquoit Bay, MA (estuary), controlled experiments documented that blooms of macroalgae were responsible for the loss of eelgrass beds at nutrient-enriched locations. Macroalgae covered eelgrass and reduced irradiance to the extent that the plants could not maintain net growth. In Hog Island Bay, VA (estuary), a dense lawn of macroalgae covered the bottom sediments. There was reduced sediment-water nitrogen exchange when the algae were actively growing and high nitrogen release during algal senescence. In Lakes Brobo (West Africa) and Okeechobee (FL), there were dramatic seasonal changes in the biomass and phosphorus content of planktonic versus attached algae, and these changes were coupled with changes in water level and abiotic turbidity. Deeper water and/or greater turbidity favored dominance by phytoplankton. In Lake Brobo there also was evidence that phytoplankton growth was stimulated following a die-off of vascular plants. The case studies from Waquoit Bay and Lake Okeechobee support conceptual models of succession from vascular plants to benthic algae to phytoplankton along gradients of increasing nutrients and decreasing under-water irradiance. The case studies from Hog Island Bay and Lake Brobo illustrate additional effects (modified sediment-water nutrient fluxes, allelopathy or nutrient release during plant senescence) that could play a role in ecosystem response to nutrient stress.

Sulfation and attrition of calcium sorbent in a bubbling fluidized bed

A bubbling fluidized bed reactor was used as a desulfurization apparatus in this study. The height of the bed was 2.5m, and the inner diameter was 9cm. The bed materials were calcium sorbent and silica sand. The effects of the operating parameters of the flue gas desulfurization including relative humidity, temperature, superficial gas velocity, and the particle size of calcium sorbent on SO2 removal efficiency and calcium sorbent conversion and attrition rate in the fluidized bed were investigated. It was found that the temperature effect in our system was negligible from 40 to 65 degrees C. A higher relative humidity had a higher calcium conversion and a higher sulfur dioxide removal efficiency. Moreover, a smaller particle size of calcium sorbent had a lower calcium conversion in the cyclone but a higher sulfur dioxide removal efficiency. A lower superficial gas velocity resulted in a higher sulfur dioxide removal efficiency and a higher calcium conversion, thus, the total volume of the flue gas treated was maximum near the minimum fluidization velocity. Finally, an attrition rate model proposed in this study could predict the elutriation rate satisfactorily.

Expression patterns of p27Kip1 and Ki-67 in cholesteatoma epithelium

OBJECTIVES

The cell cycle must be involved in cell proliferation of the epithelium of middle ear cholesteatoma Cyclins and cyclin-dependent kinase (CDK) complexes have important regulatory roles during cell cycle progression. Cyclin-CDK complexes are in turn regulated by the cyclin-dependent kinase inhibitors (CDKIs), which generally inhibit cell cycle progression. One of the important CDKI members is p27(Kip1). The goal of this study is to evaluate the expression of p27(Kip1) and Ki-67, a proliferation marker, in cholesteatoma and in the skin of the external ear canal.

METHODS

The expressions of p27(Kip1) and Ki-67 in cholesteatoma epithelium (n = 20) and ear canal epithelium (n = 7) were investigated by an immunohistochemical technique.

RESULTS

In cholesteatoma epithelium specimens, the expression of p27(Kip1) was observed from the parabasal layer to the granular layer, but not in the basal layer. Ki-67 was expressed dominantly in the basal and parabasal cell layers. Their expressions tend to be increased compared with their expressions in the normal ear canal skin. The expression pattern of the proliferation marker Ki-67 in the epithelial layers of two groups was inversely related to the expression of p27(Kip1).

CONCLUSIONS

In cholesteatoma, the expressions of CDKI and Ki-67 were both increased in this study. The ability to inhibit proliferative activity was also increased in the cholesteatoma epithelium. The expression pattern of the proliferation marker Ki-67 in the epithelial layers was inversely related to the expression of p27(Kip1). Not only is the proliferation activity increased, but also the ability to inhibit hyperproliferation is increased in the cholesteatoma epidermis. Despite increased proliferative activity in the cholesteatoma epidermis, epithelial cells still retain the capability to prevent cell cycle arrest by means of p27(Kip1).

Clinical experiences with acute mastoiditis--1988 through 1998

The incidence of acute mastoiditis has declined dramatically during the postantibiotic era. Even so, antibiotic-resistant or unusual pathogens can still cause this disease entity. At our hospital, we documented an increase in antibiotic-resistant and atypical pathogens such as Actinomyces spp. and Mycobacterium tuberculosis. In this paper, we discuss the optimal diagnosis and treatment strategy for acute mastoiditis, and we describe our retrospective review of 13 patients with mastoiditis who were treated at our hospital from 1988 through 1998. Eight of these patients recovered following treatment with intravenous antibiotics, with or without myringotomy, and five who had complications of disease were managed surgically. Among these five, one developed chronic otitis media and one developed cholesteatoma 3 years later. For patients with acute mastoiditis, we emphasize the need to be aware of any unusual pathogens that do not respond to empiric antibiotic therapy.

Protective role of superoxide dismutase in rat eustachian tubal mucosa against acute otitis media induced by upper respiratory tract infection

Superoxide dismutase has been known to play a role as an anti-oxidative system against oxidative injury during acute inflammation. To investigate the role of superoxide dismutase in eustachian tubal mucosa during acute otitis media (AOM), an animal model was made. Sprague-Dawley rats were inoculated with Streptococcus pneumoniae through the nasal cavity following development of virus-induced upper respiratory infection. The animals were divided into three groups according to their tympanic cavity conditions following bacterial inoculation; inoculated animals with no resultant AOM (no-AOM), animals with resultant AOM (AOM) and animals with resolving otitis media (recovery). The changes of superoxide dismutase in each tubal mucosa were compared with that of the normal control using immunohistochemistry and immunoblotting methods. On Western blot, there were little changes of optical density and surface area in no-AOM (213.5 +/- 22.4, 13.2 +/- 0.8 mm2) and recovery group (219.3 +/- 18.7, 14.8 +/- 0.7 mm2) compared to the normal control (223.5 +/- 26.2, 16.7 +/- 0.4 mm2). However, a marked decrease was found in the AOM model (167.6 +/- 19.3, 6.5 +/- 0.9 mm2). These findings suggest that superoxide dismutase may play a role in protecting tubal mucosa from free radical injury during AOM.

Seroprevalence of GB virus C/hepatitis G virus-RNA and anti-envelope antibody in high-risk populations in Taiwan

BACKGROUND

GB Virus C (GBV-C)/hepatitis G virus (HGV) was identified in 1995-1996 as a transfusion-transmissible virus. The diagnosis of GBV-C/HGV infection is based on the detection of GBV-C/HGV-RNA by using polymerase chain reaction. Recently, an enzyme immunoassay detecting the antibodies to the viral protein, E2 envelope protein (anti-envelope) of GBV-C/HGV, has been developed.

METHODS

Serum GBV-C/HGV-RNA and anti-envelope antibody were determined in 76 cases of intravenous drug users (IVDU), 76 patients with regular hemodialysis and in 80 prostitutes to evaluate the GBV-C/HGV infection rate among high-risk populations in Taiwan. Seventy-six healthy blood donors were randomly selected and were used as a control group.

RESULTS

The prevalence of GBV-C/HGV-RNA in high-risk populations was 33% for IVDU, 16% for patients with hemodialysis and 13% for prostitutes, which was significantly higher than the 3% obtained in the control group (P < 0.05 for all groups). The prevalence of anti-envelope antibody was 13% for IVDU, 21% for patients with hemodialysis and 23% for prostitutes, which was not significantly different from the control group (11%). Among the 99 subjects who had positive GBV-C/HGV markers, 97 were tested for exclusive positivity for either GBV-C/HGV-RNA or anti-envelope antibody.

CONCLUSIONS

The presence of serum anti-envelope antibody usually indicates the clearance of serum GBV-C/HGV-RNA in patients infected with GBV-C/HGV. GBVirus-C/HGV infection in high-risk populations, determined by the presence of serum GBV-C/HGV-RNA, may underestimate the true level of past and present infection.

Clinical, virologic and pathologic significance of elevated serum gamma-glutamyl transpeptidase in patients with chronic hepatitis C

BACKGROUND

Elevated serum gamma-glutamyl transpeptidase (GGT) is often seen in patients with chronic hepatitis C virus (HCV) infection and is associated with a poor response to interferon treatment. The pathogenesis of these phenomena is unclear. Therefore, we assessed the prevalence of elevated serum GGT in Chinese patients with chronic hepatitis C and evaluated the clinical, biochemical, virologic and histologic features of this phenomenon.

METHODS

One hundred and twelve patients with biopsy-proven chronic hepatitis C were enrolled. Patients who were habitual alcohol drinkers, alcoholics or had diabetes mellitus were excluded.

RESULTS

Forty-three (38.4%) of 112 patients had elevated serum GGT (> 60 U/l). Patients with elevated serum GGT had significantly higher serum levels of alanine and aspartate aminotransferases, alkaline phosphatase and total bilirubin, significantly higher histologic scores of liver lobular necro-inflammation and fibrosis when compared to patients with normal serum GGT. Elevated serum GGT was not correlated to serum HCV RNA titer or HCV genotype. Multivariate logistic regression analysis showed that a histologic fibrotic score > or = 2 was the only significantly independent predictor associated with elevated serum GGT. Fifty-seven of 112 patients completed a six-month course of interferon treatment. Patients with elevated serum GGT had a significantly lower sustained response rate to interferon when compared to patients with normal serum GGT (8% vs 30%, p = 0.042).

CONCLUSIONS

Elevated serum GGT in chronic hepatitis C patients was frequently associated with more severe hepatic fibrosis or cirrhosis and may, in part, account for poor response to interferon therapy.

Evaluation of gallbladder motility in patients with liver cirrhosis: relationship to gallstone formation

To investigate the postprandial gallbladder motility, including emptying and refilling, in cirrhotic patients and to evaluate the relationship to the presence of gallstones and various humoral mediators, 82 patients with liver cirrhosis and 40 age- and sex-matched healthy subjects were enrolled into this study. Postprandial gallbladder volumes were measured with ultrasonography every 15 min for 2 hr. Plasma levels of estradiol, testosterone, substance P, and nitrate/nitrite were also measured. Cirrhotic patients showed a higher prevalence of gallstones than healthy subjects (41% vs 15%, P = 0.003), and the prevalence increased with the progression of liver cirrhosis (Child-Pugh class A: 26%, B: 44%, and C: 65%, P = 0.02). Plasma levels of estradiol, testosterone, and substance P, and nitrate/nitrite and estradiol/testosterone ratios were not different between cirrhotic patients with and without gallstones. However, postprandial refilling of the gallbladders was significantly impaired in patients with cirrhosis, especially in those combined with gallstones. There was no significant difference in the postprandial gallbladder motility between cirrhotic patients with and without elevated plasma levels of estradiol, testosterone, and substance P and nitrate/nitrite, and estradiol/testosterone ratios. Gallstones were common in patients with liver cirrhosis and the prevalence increased with the progression of liver diseases. Sex hormones, substance P, and nitrate/nitrite did not play major roles in the formation of gallstones in cirrhotic patients. Refilling of the gallbladder was significantly impaired in patients with liver cirrhosis, especially in those with gallstones, and may play an important role in the pathogenesis of gallstones.