Selective suppression by bunazosin of alpha-adrenergic agonist evoked elevation of intraocular pressure in sympathectomized rabbit eyes

PURPOSE

To determine whether there is alpha 1-adrenergic receptor heterogeneity associated with the regulation of intraocular pressure (IOP) and mydriasis in rabbits, the authors tested the hypothesis by characterizing the ability of the selective alpha 1-adrenergic antagonist, bunazosin, to block the ocular hypertensive and mydriatic responses to alpha 1-adrenoceptor stimulation by either norepinephrine (NE) or phenylephrine (PE).

METHODS

The effects of topical application of bunazosin on IOP and pupillary diameter were measured in unilateral superior cervical ganglionectomized (SCGX) rabbits after exposure to either NE or PE.

RESULTS

Bunazosin (0.1%) alone only lowered the IOP in the normal eye and did not elicit a pupillary response on either side. NE (0.01-1.0%) by itself caused a concentration-dependent rise in IOP on both sides, but mydriasis did not occur on the normal side. In SCGX eyes, the sensitivity of the IOP response to NE increased tenfold over that measured on the normal side. Unlike on the normal side, concentration-dependent mydriatic responses occurred with 0.1 and 1% NE. After pretreatment with bunazosin (0.1%), neither NE (0.1%) nor PE (0.1%) evoked a rise in IOP. However, the mydriatic response to either one of these agonists in the SCGX eyes was less affected. By contrast, pretreatment with the alpha 2-adrenergic antagonist, 0.5% yohimbine, did not change the IOP increase elicited by 0.1% NE.

CONCLUSIONS

These results suggest that the alpha 1-adrenergic receptors that regulate IOP and pupillary diameter are different from one another in the rabbit.

Detection of point mutations of the phenylalanine hydroxylase gene and prenatal diagnosis of phenylketonuria

The known mutant alleles of the human phenylalanine hydroxylase (PAN) gene were analyzed in 25 phenylketonuria (PKU) families from North China by using polymerase chain reaction and allele-specific oligonucleotide dot blot hybridization techniques. The results showed that the six mutations analyzed accounted for 62% of all PKU genes. The three most frequent mutations were R243Q, R413P and Y204C. Seven prenatal gene diagnoses were carried out in 6 PKU families and were confirmed after birth or by examination of aborted materials.

[Effect of trigeminal denervation on rabbit corneal epithelium]

To investigate the effects of trigeminal denervation on the corneal epithelium, left postganglionic trigeminal neurotomy via intracranial approach was performed in 22 rabbits. Among 16 rabbits survived successfully, 13 denervated eyes (81%) showed corneal epithelial abnormalities that included 4 epithelial defects and 9 epithelial opacities. The remaining 3 eyes were normal. Histological examination showed many atrophic epithelial cells and the thinning of the corneal epithelial layer in the denervated eyes with corneal opacities. There was no abnormality in corneal stroma or endothelium. The ratio of epithelial to total corneal thickness calculated by a computer-assisted image analyzer was 6.5 +/- 2.1 (%) in control eyes and 3.8 +/- 1.9 (%) in the denervated eyes, the two values being significantly statistically different (p less than 0.001).

[Effects of insulin on expression of oncogenes in CWE mouse brain]

By RNA dot blot hybridization, we observed the expression of c-myc, c-fos, Ha-ras and erbB genes in normal brain of CWE mouse after the injection of insulin. Transcription of the c-myc and c-fos genes is greatly increased, which peaks approximately 2 h after insulin stimulation, decreases in 6 h and returns to the initial levels within 48 h. The alteration in Ha-ras transcription appears more complex; its expression decreases first but increases subsequently. We also detected the expression of erbB gene which decreases after the injection of insulin. The results suggest that c-myc, c-fos, Ha-ras and erbB might be directly involved in growth control. Their protein products might play a role in intracellular signal transduction.

[The expression of oncogenes in the development of human brain]

Seven oncogenes (c-myc, L-myc, N-myc, v-erbB, c-fos, Ha-ras and mos) were used as the probe to detect the total RNA of every part (cerebellum, temporal folium, frontal folium and occipital folium) in human brain from 2 cases of 6 mon fetus and the total RNA in fetal development (4 mon, 5 mon, 6 mon, 7 mon, and newborn) of human brain tissue by RNA dot hybridization analysis. The results showed that most oncogenes were expressed at high level in cerebellum and occipital folium of 6 mon fetus and at low level in temporal folium; there was similar expression of c-myc, L-myc and N-myc in fetal development of human brain tissue, and the highest level was in the 5 mon fetal brain. There was no expression of erbB gene in normal human brain. The high level expression of Ha-ras and c-fos genes was in the middle and later stages of fetal development. These results suggested that c-myc, L-myc, N-myc, erbB, Ha-ras, c-fos and mos genes might play an important role in the fetal development of human brain.

[A review on the chemical constituents of Annona plants]

The paper reviews the progress in the research on Annona plants, including the structure of chemical constituents, spectroscopic characteristics and physiological activities. A new kind of anticancer constituent is also introduced.

Infectivity determinants encoded in a conserved gene block of human herpesvirus-6

The nucleotide sequence was determined for a 9.3 kb BamHI DNA fragment derived from a cosmid clone (Lorist 6) library of the 160 kb human herpesvirus-6 (HHV-6) strain U1102 genome. Analysis of the sequence showed two different sources for the DNA; 8.0 kb was derived from HHV-6, while 1.3 kb was derived from the right repeat of transposon Tn10, the insertion sequence (IS) element IS10R. The IS element sequence is shown to be derived from the host bacteria of the plasmid. The HHV-6 sequence represents a highly conserved part of the genome encoding 15% of the genes conserved among the other human herpesviruses in only 5% of the genome. Six genes were identified, five encoding products with amino acid sequence similarity to homologues in herpes simplex virus (HSV), Varicella Zoster Virus (VZV), human cytomegalovirus (CMV) and Epstein-Barr Virus (EBV). All had closest amino acid similarity to CMV proteins. Three clustered structural genes, included glycoprotein H, a major conserved determinant of infectivity, were jointed to a putative dUTPase homologue in an arrangement distinct to CMV and HHV-6. In the other herpes viruses these genes are separated by over 50 kb. The gene at this point of genetic rearrangement had no sequence similarity to proteins of other herpesviruses. However, there is a protein at this locus in CMV with similar composition and character. Both appear to be highly glycosylated, secreted glycoproteins with repetitive elements similar to those of human mucins. Comparison of sequence available in the HHV-6 GS strain also shows this to be a variable region (5% nucleotide differences) in an overall conserved DNA sequence (0.5%).

Rat central amygdaloid nucleus projections to the bed nucleus of the stria terminalis

The projections from the central amygdaloid nucleus (Ce) to different subdivisions of the bed nucleus of the stria terminalis (BNST) were investigated using retrograde transport of fluorescent dyes. Iontophoretic injections of either Fast Blue (FB) or bisbenzimide (BB) were applied to the anterior medial, posterior medial, anterior lateral and posterior lateral parts of the bed nucleus of the stria terminalis. The anterior medial BNST receives projections from caudal part of medial Ce (CeM). The posterior medial BNST receives projections specifically from the intermediate subdivision of Ce, though in some cases projections from the ventral subdivision (CeV) of Ce were seen. The anterior lateral BNST receives projections primarily from the caudal lateral Ce (CeL) as well as middle and caudal part of CeM. The posterior lateral BNST receives projection from rostral CeL as well as the CeV and lateral capsular Ce. In general, the results indicate that the major subdivisions of the BNST receive projections from Ce subdivisions having similar connections with diencephalic or brainstem cell groups. Additional evidence is presented suggesting that Ce-BNST projections are part of an extensive system of intrinsic connections linking similar groups of neurons in both the Ce and BNST as well as within Ce.

[A study on characters of liver isoferritin]

The characters of liver isoferritin from Wistar rat, normal human and patient with hepatocellular carcinoma (HCC) were studied. The ratio of iron to protein of liver isoferritin from patient with HCC were 0.021, which accounts for about one-twelfth of that of liver isoferritin from normal human. The molecular weights of liver isoferritin from normal human and the patient with HCC were 20.5 kd and 21.5 kd, respectively. The electrophoresis patterns of liver isoferritin from both Wistar rat and patient with HCC showed one band, but two bands from normal human. There was cross reaction in immunity among isoferritins from normal human liver, Wistar rat liver and horse spleen by double immunodiffusion. The PAGE patterns of liver isoferritin from different sources could be clearly differentiated. The data presented may serve as a good reference for further study of the relationship between the structure and function of ferritin and may be used practically in clinical medicine.

A VH clonal deficit in human immunodeficiency virus-positive individuals reflects a B-cell maturational arrest

A major feature of human immunodeficiency virus (HIV) infection is disordered B-cell function, which paradoxically includes both pathologic overactivity (elevated serum antibodies, lymphadenopathy, and increased risk for lymphoma) and underactivity (impaired antibody immunity, particularly to bacterial polysaccharide antigens). B-cell immune dysfunction contributes significantly to HIV-related morbidity and also represents an obstacle to eventual definitive treatment by anti-HIV immunization. Our laboratory has recently identified in normal B-cell populations certain VH gene subfamilies with a developmentally regulated pattern of utilization. In particular, B cells bearing rearranged VH3L were rare in the germinal center but uniformly abundant in the blood and lymphoid mantle zone. We used this index gene subfamily as a clonal criterion for the pattern of B-cell development in lymphocytes of HIV-positive individuals. In a series of 19 HIV-positive subjects, a striking deficit of VH3L B cells was observed; in contrast, none of the 16 normal subjects showed this abnormality. Other VH subfamilies (VH1N, VH4/6, and VH5N) were unaffected in the HIV-positive patients. This VH3L clonal deficit and other recent phenotype and histopathologic findings suggest that the general B-cell dysfunction in HIV is due to a discreet maturational arrest at the germinal center stage.

Congenital anterior urethral valves and diverticula--analysis of 50 cases

Fifty patients with anterior urethral valvular obstruction were reviewed. All of them had difficulty in urination, 15 patients had recurrent high fever, 8 patients had features of renal failure, and 5 patients had a reducible swelling at the penoscrotal junction. With voiding cystourethrograph, distension of the proximal urethra was seen in all patients. Diverticula of the urethra could be demonstrated in 15 patients. Eight patients had unilateral, and 2 patients had bilateral vesicoureteral reflux. With intravenous pyelograph, unilateral hydronephrosis was seen in 4 and bilateral hydronephrosis was seen in 19. Excision of the valve and/or diverticulum with primary repair was performed in 29 patients, 28 were cured, 1 died of renal failure 8 years postoperatively. Multi-stage procedures were performed in 7 patients. Transurethral fulguration of the valve was performed in 14 patients. Nine patients were cured, secondary operations were needed in 5 patients.

Melanoma in a patient treated for psoriasis

Psoriasis, ultraviolet light, and coal tar have been associated with the development of cutaneous malignancy. We have described a 32-year-old psoriatic man who developed a melanoma after 16 years of treatment with ultraviolet light and coal tar. This is the only case of melanoma occurring in a patient treated for psoriasis reported in the world literature.

Allopurinol-hypersensitivity vasculitis and liver damage

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