Biomedical subjects

B Yang

Publications and source records attributed to B Yang.

At least 109 records · Page 6Linked to original sources

PubMed2000

Carbon dioxide permeability of aquaporin-1 measured in erythrocytes and lung of aquaporin-1 null mice and in reconstituted proteoliposomes.

Measurements of CO(2) permeability in oocytes and liposomes containing water channel aquaporin-1 (AQP1) have suggested that AQP1 is able to transport both water and CO(2). We studied the physiological consequences of CO(2) transport by AQP1 by comparing CO(2) permeabilities in erythrocytes and intact lung of wild-type and AQP1 null mice. Erythrocytes from wild-type mice strongly expressed AQP1 protein and had 7-fold greater osmotic water permeability than did erythrocytes from null mice. CO(2) permeability was measured from the rate of intracellular acidification in response to addition of CO(2)/HCO(3)(-) in a stopped-flow fluorometer using 2',7'-bis-(2-carboxyethyl)-5-(and -6)-carboxyfluorescein (BCECF) as a cytoplasmic pH indicator. In erythrocytes from wild-type mice, acidification was rapid (t((1)/(2)), 7.3 +/- 0.4 ms, S.E., n = 11 mice) and blocked by acetazolamide and increasing external pH (to decrease CO(2)/HCO(3)(-) ratio). Apparent CO(2) permeability (P(CO(2))) was not different in erythrocytes from wild-type (0.012 +/- 0.0008 cm/s) versus null (0.011 +/- 0.001 cm/s) mice. Lung CO(2) transport was measured in anesthetized, ventilated mice subjected to a decrease in inspired CO(2) content from 5% to 0%, producing an average decrease in arterial blood pCO(2) from 77 +/- 4 to 39 +/- 3 mm Hg (14 mice) with a t((1)/(2)) of 1.4 min. The pCO(2) values and kinetics of decreasing pCO(2) were not different in wild-type versus null mice. Because AQP1 deletion did not affect CO(2) transport in erythrocytes and lung, we re-examined CO(2) permeability in AQP1-reconstituted liposomes containing carbonic anhydrase (CA) and a fluorescent pH indicator. Whereas osmotic water permeability in AQP1-reconstituted liposomes was >100-fold greater than that in control liposomes, apparent P(CO(2)) (approximately 10(-3) cm/s) did not differ. Measurements using different CA concentrations and HgCl(2) indicated that liposome P(CO(2)) is unstirred layer-limited and that HgCl(2) slows acidification because of inhibition of CA rather than AQP1. These results provide direct evidence against physiologically significant AQP1-mediated CO(2) transport and establish an upper limit to the CO(2) permeability through single AQP1 water channels.

Animals↗

PubMed2000

nSec1 binds a closed conformation of syntaxin1A.

The Sec1 family of proteins is proposed to function in vesicle trafficking by forming complexes with target membrane SNAREs (soluble N-ethylmaleimide-sensitive factor [NSF] attachment protein [SNAP] receptors) of the syntaxin family. Here, we demonstrate, by using in vitro binding assays, nondenaturing gel electrophoresis, and specific neurotoxin treatment, that the interaction of syntaxin1A with the core SNARE components, SNAP-25 (synaptosome-associated protein of 25 kD) and VAMP2 (vesicle-associated membrane protein 2), precludes the interaction with nSec1 (also called Munc18 and rbSec1). Inversely, association of nSec1 and syntaxin1A prevents assembly of the ternary SNARE complex. Furthermore, using chemical cross-linking of rat brain membranes, we identified nSec1 complexes containing syntaxin1A, but not SNAP-25 or VAMP2. These results support the hypothesis that Sec1 proteins function as syntaxin chaperons during vesicle docking, priming, and membrane fusion.

Animals↗

PubMed2000

Appropriate tissue- and cell-specific expression of a single copy human angiotensinogen transgene specifically targeted upstream of the HPRT locus by homologous recombination.

Development of experimental models by genetic manipulation in mice has proven to be very useful in determining the significance of particular genes in the development of or susceptibility to hypertension. Advances in molecular genetics, transgenic mouse technology, and physiological measurements in mice provided an opportunity to go a step further and develop models to analyze the physiological significance of specific gene variants potentially causing hypertension. In this report, we describe the development of a human angiotensinogen transgenic mouse model generated by targeting the human angiotensinogen gene upstream of the mouse HPRT locus by homologous recombination. The main benefit of this transgenic mouse model is that the human angiotensinogen gene is inserted into the mouse genome as a single copy at a predefined locus and in a specific orientation-a process that can be repeated utilizing other variants of this gene. We establish the validity of this approach by showing that the hAGT(hprt) mice have normal tissue- and cell-specific expression of the human angiotensinogen gene and normally produce and process the hAGT protein at physiological levels.

Angiotensinogen↗

PubMed2000

Mutations of the calcium-sensing receptor (CASR) in familial hypocalciuric hypercalcemia, neonatal severe hyperparathyroidism, and autosomal dominant hypocalcemia.

The calcium-sensing receptor (CASR) is a plasma membrane G protein coupled receptor that is expressed in the parathyroid hormone (PTH) producing chief cells of the parathyroid gland and the cells lining the kidney tubule. By virtue of its ability to sense small changes in circulating calcium concentration ([Ca(2+)](o)) and to couple this information to intracellular signaling pathways that modify PTH secretion or renal cation handling, the CASR plays an essential role in maintaining mineral ion homeostasis. Inherited abnormalities of the CASR gene located on chromosome 3p13.3-21 can cause either hypercalcemia or hypocalcemia depending upon whether they are inactivating or activating, respectively. Heterozygous loss-of-function mutations give rise to familial (benign) hypocalciuric hypercalcemia (FHH) in which the lifelong hypercalcemia is asymptomatic. The homozygous condition manifests itself as neonatal severe hyperparathyroidism (NSHPT), a rare disorder characterized by extreme hypercalcemia and the bony changes of hyperparathyroidism which occur in infancy. The disorder autosomal dominant hypocalcemia (ADH) is due to gain-of-function mutations in the CASR gene. ADH may be asymptomatic or present with neonatal or childhood seizures. A common polymorphism in the intracellular tail of the CASR, Ala to Ser at position 986, has a modest effect on the serum calcium concentration in healthy individuals.

Calcium↗

PubMed2000

Tear secretion by lacrimal glands in transgenic mice lacking water channels AQP1, AQP3, AQP4 and AQP5.

The expression of three aquaporin (AQP)-type water channels has been reported in the lacrimal gland: AQP5 in the apical membranes of acinar and duct cells, AQP4 in the basolateral membranes of acinar cells, and AQP1 in microvascular endothelia. Recent experiments indicate that water movement through AQP5 in the salivary gland is important in saliva secretion. To investigate the role of aquaporins in lacrimal gland function, basal and pilocarpine-stimulated tear secretion was compared in wildtype mice and knockout mice lacking AQP1, AQP4 and AQP5, as well as AQP3, which was found here to be expressed in the basolateral membrane of acinar cells. Tear fluid was collected in anesthetized mice using microcapillary tubes before and at 4 min intervals after pilocarpine administration. Tear fluid volumes were (in microliter per 4 min, S.E.): 0.69 +/- 0.06 (wildtype mice), 0.70 +/- 0.07 (AQP1 -/-), 0.81 +/- 0.13 (AQP3 -/-), 0.62 +/- 0.14 (AQP4 -/-), and 0.78 +/- 0.09 (AQP5 -/-) (differences not significant). Chloride concentrations (average 155 +/- 13 mM) measured by a fluorescence assay were also not different in tear fluid collected from wildtype vs aquaporin null mice. These findings provide direct evidence against an essential role for aquaporins in lacrimal gland fluid secretion. The requirement for aquaporins in salivary but not lacrimal gland secretion, may involve the substantially slower fluid secretion rate across lacrimal gland acinar cells.

Animals↗

PubMed2000

Efficacy and safety of preoperative lobar or segmental ablation via transarterial administration of ethiodol and ethanol mixture for treatment of hepatocellular carcinoma: clinical study.

Transarterial embolization (TAE) using various thrombotic substances for unresectable hepatocellular carcinoma (HCC) performed on many patients has resulted in a better survival rate. We evaluated the efficacy and clinical safety of using an Ethiodol-ethanol mixture as the embolizer for treatment of HCC and the possibility of a surgical approach for inoperable tumors after TAE. Twenty patients with HCC who underwent TAE and tumor resection were included in the study. Initially, eight had increased retention rate of indocyanine green dye via intravenous injection (0.5 mg/kg) at 15 minutes (ICGR15), and six had an insufficient residual volume that precluded them from undergoing tumor resection. TAE was performed by slowly infusing the mixture of Ethiodol and ethanol into the artery supplying the tumor until dual hepatic artery and portal vein embolization was achieved. Serum levels of alanine aminotransferase increased after embolization, but all biochemistry studies reverted to normal within 2 weeks. A decreased tumor size (n = 15), improved ICG (n = 8), and increased volume of the nonembolized lobe (n = 10) were noted. The operations performed were right lobectomy (n = 11), extended right lobectomy (n = 3), left lobectomy (n = 2), extended left lobectomy (n = 2), and wedge resection (n = 2), which included patients who did not want to undergo major hepatectomy. Complete tumor necrosis was found in seven cases. All patients survived with no associated complications. The 1-year survival rate was 95%. Transarterial Ethiodol and ethanol administration creating dual hepatic artery and portal vein embolization was a safe and efficacious method for treating HCC. It effectively decreases tumor size, causes compensatory hepatic hypertrophy, and improves the ICGR15, which allows a wider range of patients to undergo liver surgery and achieve better survival.

Adult↗

PubMed2000

Termination of early pregnancy in the mouse, rat and hamster with DL111-IT and RU486.

The effectiveness of DL111-IT and RU486 given alone and in combination for terminating early pregnancy was tested in the rat, mouse, and hamster. In the mouse and rat, the combination of RU486 and DL111-IT is much more effective in terminating pregnancy than either of the two compounds used alone (single or multiple treatment). A low-effective dose of DL111-IT in combination with a non-effective or a sub-effective dose of RU486, exerted additive or synergistic effects resulting in resorption of embryos and termination of pregnancy. The serum progesterone concentrations were significantly suppressed by these combinations when pregnancy was terminated. In the hamster, single treatment with DL111-IT plus RU486 exhibited a strong effect on interrupting early pregnancy. The ED50 of RU486 in combination of a non-effective dose of DL111-IT was decreased to 163-fold lower dose than RU486 given alone. It is concluded that in mouse, rat, and hamster, the synergistic action between DL111-IT and RU486 not only greatly enhances efficacy in terminating pregnancy but also reduces substantially the dose required to produce this effect.

Abortifacient Agents, Nonsteroidal↗

PubMed2000

Synergistic effects of DL111-IT combined with mifepristone on termination of early pregnancy in rhesus monkeys.

The objectives of this study were to determine the synergistic effects of DL111-IT in combination with mifepristone (RU486) on termination of early pregnancy in rhesus monkeys. Pregnancy was confirmed by tactile sensation of pregnant uterus via anus with finger and ultrasound examination. Pregnancy termination was obtained with vaginal bleeding and abortion materials including fetuses and placentae after treatment. With multiple doses of DL111-IT or RU486 given alone between d24 and d50 of gestation, pregnancy arrests were obtained in 40% (2/5) of monkeys treated with DL111-IT intramuscularly (im) (25 mg x kg(-1) x d(-1) x 3 days), in 20% (1/5) of monkeys treated with 9 mg x kg(-1) x d(-1) x 2 days, and 4.5 mg x kg(-1) on day 3 with RU486 intragastrically (ig). DL111-IT (25 mg x kg(-1) on day 1, im) in combination with RU486 (the same treatment as above) resulted in 100% (10/10) termination of pregnancy and uterine bleeding lasted 6.6 +/- 1.3 days. RU486 (as above treatment) in combination with misoprostal (Miso, 109 microg x kg(-1) on day 3, ig) showed 71.4% (5/7) termination of pregnancy, and uterine bleeding lasted 12.9 +/- 9.6 days. The synergistic effect of DL111-IT plus RU486 enhances termination of early pregnancy and significantly shortens the bleeding time than RU486 plus Miso does in rhesus monkeys.

Abortifacient Agents, Nonsteroidal↗

PubMed2000

Differential sensitivity of mouse neural crest cells to ethanol-induced toxicity.

Neural crest cells (NCCs) have been identified as an important target population relative to ethanol-induced teratogenicity in both mouse and avian models. Additionally, whole embryo culture mouse models have shown strain-related differences in sensitivity to ethanol-induced damage following acute exposure during early NCC development. That differential sensitivity of NCCs may contribute to these strain differences has been unexplored. For this purpose, cultured NCCs from an inbred mouse strain (C57BL/6J; C57) that is more sensitive to ethanol-induced teratogenicity than an outbred strain (ICR) were compared. This study showed that the incidence of cell death was significantly higher for the C57 NCCs than those from the ICR strain at all ethanol concentrations tested, and as early as 12 hours after initial exposure to 100 mM ethanol. The lateral mobility of the membrane lipids was faster and the membrane GM1 content was lower in C57 cells than ICR cells both under control conditions and at all doses and times tested. Ethanol exposure resulted in significant increases in the membrane lipid lateral mobility, and decreases in the membrane GM1 content that occurred in a dose and time-dependent manner in the NCCs from both strains. A significant correlation was found between the GM1 content and lateral mobility of the membrane lipids, the lateral mobility of membrane lipids and cell viability, as well as the GM1 content and cell viability in the NCCs from both strains. These results suggest that different strain sensitivities to ethanol-induced teratogencity may lie, at least in part, in the interstrain differential response of the NCC population and that the vulnerability of the NCCs to ethanol-induced death may be related to their endogenous membrane GM1 content.

Animals↗

PubMed2000

Effect of dietary supplementation with sea buckthorn (Hippophaë rhamnoides) seed and pulp oils on the fatty acid composition of skin glycerophospholipids of patients with atopic dermatitis.

Sea buckthorn (Hippophaë rhamnoides) seed and pulp oils have traditionally been used for treating skin diseases in China and Russia, but are not widely used in other countries. A placebo-controlled, parallel study was carried out to investigate the effects of these oils on the fatty acid composition of skin glycerophospholipids of patients with atopic dermatitis. Sixteen patients ate 5 g of sea buckthorn seed oil, pulp oil, or paraffin oil daily for 4 months. Skin fatty acids were analyzed with gas chromatography before and after treatment. The seed oil slightly increased the proportion of docosapentaenoic acid (22:5n-3) and decreased the proportion of palmitic acid (16:0) in skin glycerophospholipids (0.05 < P < 0.1). The levels of the other fatty acids remained stable. The results show that the fatty acid composition of skin glycerophospholipids is well buffered against short-term dietary modification.

Journal Article↗

PubMed2000

Sea buckthorn berry oil inhibits platelet aggregation.

A small-scale preliminary cross-over study was conducted to investigate the effects of supercritical CO(2)-extracted sea buckthorn berry oil (SBO) on some risk factors of cardiovascular disease. Special features of the oil are high proportions of palmitic (16:0), oleic (18:1n-9), palmitoleic (16:1n-7), linoleic (18:2n-6), and alpha-linolenic (18:3n-3) acids as well as vitamin E, carotenoids, and sterols. Twelve healthy normolipidemic men were recruited and each volunteer consumed SBO and fractionated coconut oil (control) 5 g per day for a period of 4 weeks in a random order (wash-out 4-8 weeks). Phospholipid fatty acids, plasma lipids, and glucose were unaffected by SBO supplementation. Instead, a clear decrease in the rate of adenosine-5'-diphosphate-induced platelet aggregation and maximum aggregation were found. This suggested the beneficial effects of SBO on blood clotting, but further studies on the dose-response effects are needed to assess the practical use of SBO supplements.

Journal Article↗

PubMed2000

Prospects for understanding avirulence gene function.

Avirulence genes are originally defined by their negative impact on the ability of a pathogen to infect their host plant. Many avirulence genes are now known to represent a subset of virulence factors involved in the mediation of the host-pathogen interaction. Characterization of avirulence genes has revealed that they encode an amazing assortment of proteins and belong to several gene families. Although the biochemical functions of the avirulence gene products are unknown, studies are beginning to reveal the features and interesting relationships between the avirulence and virulence activities of the proteins. Identification of critical virulence factors and elucidation of their functions promises to provide insight into plant defense mechanisms, and new and improved strategies for the control of plant disease.

Amino Acid Sequence↗

PubMed2000

Expression of Bax, Bcl-2, and P53 in progressive multifocal leukoencephalopathy.

It has been shown in vitro that JC viral protein can form a complex with wild-type p53 protein, which is a key regulator of both cell proliferation and cell death. Cellular factors, Bax and Bcl-2, are two essential downstream elements involved in p53-dependent apoptosis. To determine whether association of JC virus with p53 protein affects the expression of Bax and Bcl-2 in viral-infected cells in progressive multifocal leukoencephalopathy (PML), we studied the expression of Bax, Bcl-2, and p53 in 14 cases from 13 PML patients by using paraffin immunohistochemistry. Seven of 13 patients were known to be HIV positive. Overexpression of p53 was found in viral-infected oligodendrocytes and some astrocytes in all 14 cases. Intense immunostaining of Bax was strongly expressed in viral-infected oligodendrocytes and astrocytes. Bax immunostaining was also found in macrophages in the demyelinating lesions. Bcl-2 was not detected in viral-infected glial cells. The expression pattern of Bax positive/Bcl-2 negative in viral-infected glial cells suggests that the oligodendrocyte may be undergoing apoptosis which may in turn contribute to the demyelinating process in PML. The coexpression of p53 and Bax in the infected glial cells suggests that p53 detected by immunohistochemistry may still maintain its wild-type function.

Adult↗

PubMed2000

Mast cell tryptase from pig lungs triggers infection by pneumotropic Sendai and influenza A viruses. Purification and characterization.

A novel trypsin-type serine proteinase, which processes the precursors of the envelope fusion glycoproteins of pneumotropic Sendai and human influenza A viruses, was purified to homogeneity from pig lungs. On SDS/PAGE, the purified enzyme gave a protein band corresponding to about 32 kDa, and has an apparent molecular mass of 120 kDa, as determined by gel permeation chromatography. Immunohistochemical staining with antibodies against this enzyme revealed that the enzyme is located in pig lung mast cells. The N-terminal 44-amino-acid sequence of the enzyme exhibits about 80% identity with those of mast cell tryptases from other species. Of the inhibitors tested, di-isopropyl fluorophosphate, antipain, leupeptin, benzamidine and a few proteinaceous inhibitors, such as mucus protease inhibitor and aprotinin, inhibited this enzyme activity. Heparin stabilized the enzyme, but high-ionic-strength conditions did not, unlike for human mast cell tryptase. The purified enzyme efficiently processed the fusion glycoprotein precursor of Sendai virus and slowly processed hemagglutinin of human influenza A virus, and triggered the infectivity of Sendai virus in a dose-dependent manner, although human mast cell tryptase beta and rat mast cell tryptase (rat MCP-7) from lungs did not process these fusion glycoproteins at all. These results suggest that mast cell tryptase in pig lungs is the possible trigger of the pneumotropic virus infections.

Amino Acid Sequence↗

PubMed2000

Vulvar intraepithelial neoplasia of the simplex (differentiated) type: a clinicopathologic study including analysis of HPV and p53 expression.

The simplex (differentiated) variant of vulvar intraepithelial neoplasia (VIN) has not been well characterized. The authors studied the clinicopathologic features of 12 cases of simplex VIN and obtained follow-up data to assess its relationship to vulvar invasive squamous cell carcinoma (InvSCC). Expression of p53 protein was analyzed immunohistochemically and compared with adjacent non-neoplastic epidermal lesions. Assessment of human papilloma virus (HPV) deoxyribonucleic acid was done by polymerase chain reaction amplification and in situ hybridization. All patients were of postmenopausal age (mean age, 66.8 years). Three patients had a history of prior vulvar InvSCC and one had a separate synchronous vulvar InvSCC. Squamous hyperplasia was present in the adjacent epidermis in 10 patients and lichen sclerosus (LS) was present in four patients. Histologically, simplex VIN differed from "classic" VIN by its highly differentiated features. The characteristic features included parakeratosis, thickened epidermis with elongated and anastomosing rete ridges, enlarged abnormal keratinocytes with premature eosinophilic cytoplasmic differentiation extending deeply within the epidermis, whorling of enlarged keratinocytes or keratin pearl formation within rete ridges, prominent intercellular bridges, and dysplastic basilar cells. One patient had minimal microinvasion (0.6 mm). Ten of 12 patients had positive p53 immunostaining staining with suprabasilar extension of p53 positive cells in each patient. The labeling index (LI) of basilar cells ranged from 0% to 99% (median, 94.5%). Non-neoplastic lesions in the adjacent epidermis had p53-positive basal cells in nine of 11 evaluable cases. The LI was significantly lower in these lesions, with a median of 4% in squamous hyperplasia and 7.5% in LS; none had suprabasilar extension of p53-positive cells. HPV (type 31/35/51) was identified in only one simplex VIN--a p53-negative lesion. Staining for p53 often delineated sharply the junction between simplex VIN and squamous hyperplasia. Four patients subsequently developed vulvar InvSCC at 5, 6, 9, and 55 months. All four InvSCCs were of the conventional keratinizing type and were HPV negative, as were the one synchronous and two prior InvSCCs. The authors conclude that (1) simplex VIN has a strong association with vulvar InvSCC and is a probable precursor lesion of HPV-negative vulvar InvSCCs, (2) HPV is very uncommon in simplex VIN and probably does not play an important role in its genesis, (3) alteration of the p53 gene appears to be involved in the development of simplex VIN, and (4) immunostaining for p53 protein may be helpful in the differential diagnosis of simplex VIN.

Aged↗

PubMed2000

Clinicopathologic reassessment of primary cutaneous B-cell lymphomas with immunophenotypic and molecular genetic characterization.

Primary cutaneous B-cell lymphomas (PCBLs) may have particular clinicopathologic characteristics distinct from their lymph node-based counterparts. It has been suggested that PCBLs should have a separate classification system. The aim of this study was to determine whether the Revised European-American Lymphoid Neoplasms (REAL) classification is applicable to PCBL. Thirty-nine cases of PCBL from 36 patients, consisting of 20 men and 16 women (median age 66 yrs), were included in this study. Paraffin-section immunohistochemistry for CD3, CD5, CD10, CD20, CD43, Bcl-2, Bcl-6, and cyclin D1 was performed in all cases. Immunostaining for immunoglobulin light chains was also performed on cases histologically diagnosed as extranodal marginal zone lymphoma (MZL) and primary cutaneous B-cell lymphoma unclassifiable (PCBLu). Polymerase chain reaction (PCR) analysis of t(14;18) was performed in all cases. Immunoglobulin heavy chain gene rearrangement (VDJ) was tested by PCR on all follicle center lymphoma (FCL), MZL, and PCBLu cases. The 39 cases consisted of 15 (39%) FCLs, 13 (33%) diffuse large B-cell lymphomas (DLCL), 9 (23%) extranodal MZL, and 2 cases of PCBLu. Anatomically, 59% of PCBLs occurred in the head and neck, of which approximately 57% were FCL. Five of six cases presenting on the lower extremity were DLCL. Follow-up data was available from all 39 patients with a mean of 50.8 months. All but two patients are alive with or without disease at last contact. One patient with DLCL died of lung metastases and the other DLCL patient died of sepsis as a complication of therapy. In all 15 cases of FCL, CD10 and/or Bcl-6 expression supported the follicle center origin of the neoplastic cells. In contrast to previous reports, we found that 53% (8 of 15) of primary cutaneous FCL had either Bcl-2 protein expression or t(14;18). Our data indicate that many cases of primary cutaneous FCL have Bcl-2 alterations similar to their nodal counterpart. We found that 95% (37 of 39) of PCBLs could be classified according to the REAL classification, supporting its applicability in cutaneous lymphomas.

Adult↗

PubMed2000

Role of water channels in fluid transport studied by phenotype analysis of aquaporin knockout mice.

Aquaporin-type water channels are expressed widely in mammalian tissues, particularly in the kidney, lung, eye and gastrointestinal tract. To define the role of aquaporins in organ physiology, we have generated and analysed transgenic mice lacking aquaporins (AQP) 1, 3, 4 and 5. Multiple phenotype abnormalities were found in the null mice. For example, in kidney, deletion of AQP1 or AQP3 produced marked polyuria whereas AQP4 deletion produced only a mild concentrating defect. Deletion of AQP5, the apical membrane water channel in the salivary gland, caused defective saliva production. Deletion of AQP1 or AQP5, water channels in lung endothelia and epithelia, resulted in a 90% decrease in airspace-capillary water permeability. In the brain, deletion of AQP4 conferred marked protection from brain swelling induced by acute water intoxication and ischaemic stroke. The general paradigm that has emerged from these phenotype studies is that aquaporins facilitate rapid near-isosmolar transepithelial fluid absorption/secretion, as well as rapid vectorial water movement driven by osmotic gradients. However, we have found many examples in which the tissue-specific expression of an aquaporin is not associated with any apparent phenotypic abnormality. The physiological data on aquaporin null mice suggest the utility of aquaporin blockers and aquaporin gene replacement in selected human diseases.

Animals↗

PubMed2000

Mooren's ulcer in China: a study of clinical characteristics and treatment.

AIMS: To investigate the clinical characteristics and compare the effects of several methods of treatment of Mooren's corneal ulcer. METHODS: 550 consecutive cases of Mooren's corneal ulcer were analysed in patients, including age, sex, laterality of eye, ulcer location, perforative rate, cure rate of surgeries, recurrent rate, the effects of conjunctiva excision, lamellar keratoplasty (LKP), and LKP plus 1% cyclosporin A eye drops. RESULTS: The average age of onset was 48.4 years of age. The ratio of males to females was 1:0. 74. 165 (30%) cases had the disease bilaterally, of which 52 (31.5%) occurred in the young age group and 113 (68.5%) in the old age group. Ulcers of 501 eyes (70.1%) were located at the limbus of the palpebral fissure. The perforation rate was 13.3%, with perforation of 41 eyes (43.2%) occurring in the young age group and 54 (56.8%) in the old age group. Postoperative recurrence rate was 25.6%. The cure rate of the first procedure of LKP plus 1% cyclosporin A eye drops was 73.7%. The final cure rate was 95.6%, and the postoperative preservation rate of the eye globe was 99.7%. CONCLUSION: This primary study provided the clinical characteristics of patients with Mooren's corneal ulcer in China. LKP plus 1% cyclosporin A eye drops was an effective treatment.

Administration, Topical↗