Molecular mechanism for duplication 17p11.2- the homologous recombination reciprocal of the Smith-Magenis microdeletion

Recombination between repeated sequences at various loci of the human genome are known to give rise to DNA rearrangements associated with many genetic disorders. Perhaps the most extensively characterized genomic region prone to rearrangement is 17p12, which is associated with the peripheral neuropathies, hereditary neuropathy with liability to pressure palsies (HNPP) and Charcot-Marie-Tooth disease type 1A (CMT1A;ref. 2). Homologous recombination between 24-kb flanking repeats, termed CMT1A-REPs, results in a 1.5-Mb deletion that is associated with HNPP, and the reciprocal duplication product is associated with CMT1A (ref. 2). Smith-Magenis syndrome (SMS) is a multiple congenital anomalies, mental retardation syndrome associated with a chromosome 17 microdeletion, del(17)(p11.2p11.2) (ref. 3,4). Most patients (>90%) carry deletions of the same genetic markers and define a common deletion. We report seven unrelated patients with de novo duplications of the same region deleted in SMS. A unique junction fragment, of the same apparent size, was identified in each patient by pulsed field gel electrophoresis (PFGE). Further molecular analyses suggest that the de novo17p11.2 duplication is preferentially paternal in origin, arises from unequal crossing over due to homologous recombination between flanking repeat gene clusters and probably represents the reciprocal recombination product of the SMS deletion. The clinical phenotype resulting from duplication [dup(17)(p11.2p11.2)] is milder than that associated with deficiency of this genomic region. This mechanism of reciprocal deletion and duplication via homologous recombination may not only pertain to the 17p11.2 region, but may also be common to other regions of the genome where interstitial microdeletion syndromes have been defined.

Antiplatelet actions of aporphinoids from Formosan plants

Seventeen aporphines were tested for antiplatelet activity. L-(+)-hemovine HCl and 7-hydroxydehydrothalicsimidine strongly inhibited platelet aggregation induced by adenosine 5'-diphosphate (ADP), arachidonic acid (AA), collagen, and platelet-activating factor (PAF). The latter showed the strongest antiplatelet activity with an IC50 of 70.4 microM against AA-induced platelet aggregation.

Protective colloids and polylactic acid co-affecting the polymorphic crystal forms and crystallinity of indomethacin encapsulated in microspheres

The co-effect of protective colloids and polylactic acid (PLA) on the polymorphic crystal forms and crystallinity of indomethacin (IMC) in IMC-loaded PLA microspheres was investigated with differential scanning calorimetry, infrared spectroscopy and x-ray diffractometry, to evaluate the polymorphic crystal forms and crystallinity of IMC encapsulated in PLA microspheres. The surfactant, sodium dodecyl sulphate (SDS), was also used as a dispersing agent. The results indicate that the polymorphism and crystallinity of IMC encapsulated in IMC-loaded PLA microspheres was dependent on the type of protective colloid and PLA used. The amorphous state and alpha-form of IMC were found in the IMC-loaded PLA microspheres prepared using polysaccharide (pectin or beta-cyclodextrin) as a protective colloid or SDS as a dispersing agent. However, the amorphous and methylene chloride solvate of IMC seemed to exist in the IMC-loaded PLA microspheres prepared with the proteins (gelatin or albumin), synthetic cellulose derivative (methyl cellulose or hydroxylpropyl methylcellulose) or the synthetic nonionic polymer (polyvinyl alcohol, polyvinyl pyrrolidone or biosoluble polymer) as a protective colloid. PLA was found to express a certain crystallinity in microspheres and not be affected by the protective colloids, but it played a more important role in influencing the crystallization of IMC during microencapsulation than the protective colloids. No interaction occurred in the physical mixture of IMC and PLA, nor in the IMC-loaded PLA microspheres.

Thermal decomposition and reconstitution of hydroxyapatite in air atmosphere

In this paper, the decomposition and reconstruction behavior of hydroxyapatite (HAP) during heating and cooling in air atmosphere were studied. The commercial HAP were chosen and gradually heated to 1500 degrees C and cooled to room temperature by a program controlled SiC heated furnace. X-ray diffraction (XRD) and Fourier-transformed infrared (FTIR) analysis were used to investigate the change of crystalline phases and functional groups of HAP at different temperatures. Weight change of samples was recorded by thermogravimetric analysis (TGA) during heating and cooling. The results revealed that HAP gradually releases its OH- ions and transforms into OHAP in the temperature of 1000-1360 degrees C. Above 1360 degrees C, the OHAP would decompose into TTCP and alpha TCP phase. The OH- stretching bands of HAP could be traced by FTIR even at the temperature of 1350 degrees C which indicates HAP decomposition. HAP does not dehydrate completely before decomposition. We speculated that some oxyapatite (OAP) might be formed during dehydration with a great amount of OHAP still left in the system even up to the temperature of decomposition. In the temperature range of 1400-1500 degrees C, there was no significant difference in XRD patterns, only TTCP and alpha TCP crystalline phases were observed. When the HAP gradually cools from 1500 degrees C, a part of TTCP and alpha TCP would directly reconstruct into OAP around 1350 degrees C. OAP existed in the temperature range of 1350-1300 degrees C during cooling. When the temperature decreased to 1290 degrees C, a part of TTCP and alpha TCP reconstructed into OHAP by rehydration reaction and OAP were rehydrated into OHAP as well. At 1100 degrees C, the rest of TTCP and alpha TCP reconstitutes into HAP. As the temperature decreases, the OHAP is gradually rehydrated and reconstituted into HAP.

Prenatal diagnosis of Charcot-Marie-Tooth disease type 1A

Charcot-Marie-Tooth disease (CMT) is the most common cause of peripheral neuropathy, with an incidence of 1: 2500 persons affected. CMT1A is caused by a submicroscopic duplication in 17p12. Several methods exist for determining a diagnosis in an individual. Many of these methods are not suitable for prenatal diagnosis. Previously, we reported the use of fluorescence in situ hybridization (FISH) to detect the common duplication found in more than 98% of individuals with CMT1A. We also have reported the validation of the FISH assay for amniotic fluid specimens and chorionic villus samples. Herein, we report our experience with testing for CMT1A in prenatal specimens.

Porphyromonas gingivalis bacteremia and subhepatic abscess after renal transplantation: a case report

A uremic patient developed subhepatic abscess, Porphyromonas gingivalis bacteremia and cytomegalovirus viremia after a renal transplantation in mainland China. P. gingivalis infection has been reported to cause gingivitis and periodontitis. Bacteremia due to P. gingivalis, however, has not been reported in the literature. We report herein a case of subhepatic abscess and bacteremia due to P. gingivalis in a renal transplant recepient who was treated successfully with the well functioning renal graft.

Precocious differentiation of the virgin Wistar-Kyoto rat mammary gland

The Wistar-Kyoto (WKY) rat strain expresses high levels of beta-casein in its virgin mammary glands. We found that the onset of beta-casein overexpression (BCO) occurs at 6 weeks of age, with morphological differentiation of the mammary gland detectable at 7 weeks of age. BCO was previously shown to be cell autonomous; however, we found that adrenal and ovarian hormones were permissive and necessary for the expression of the BCO phenotype, indicating that the genetic variation that initiates BCO from within the mammary epithelium can only manifest BCO in the presence of virgin hormone levels. Sequencing of the WKY and Wistar-Furth (WF) rat beta-casein promoters showed them to be identical. Culture of primary rat mammary epithelial cells (RMEC) under lactogenic conditions revealed that expression of beta-casein was independent of epidermal growth factor (EGF) in RMEC from virgin WKYv, but was dependent in WFv, RMEC. RMEC from a pregnant WFp responded similarly to WKYv RMEC, suggesting that EGF-independent beta-casein expression occurs naturally in differentiated rat mammary epithelium. However, induction of beta-casein expression in RMEC from immature WKY rats was also independent of EGF, indicating that the induction as well as maintenance of BCO do not require EGF. We suggest that an EGF-independent signaling pathway, arising from a trans-acting inherited effector(s), underlies BCO.

Rapidly resorptive exudative retinal detachment in a patient with renogenic hypertension: case report

We present an 18-year-old woman who developed rapidly resorptive exudative retinal detachment (ERD) due to chronic renal failure and renogenic hypertension. In July 1998, the patient came to our clinic because of a 2-month-history of progressively deteriorating visual acuity. Initially examination of the fundi revealed typical hypertensive retinopathy. Two weeks later, the patient was admitted due to hypertension and consulted our ophthalmic department again. In addition to hypertensive retinopathy, the fundi showed high bullous ERD, involving the temporal retinas in both eyes. Intensive medical therapy was begun, including blood pressure control and maintenance of body fluid and electrolyte balance, resulting in almost complete regression of retinal detachment within two days. The visual acuity improved during the following 2 weeks. The clinical features and treatment response in this rare case indicate that multiple factors, including fluids overload, hypertension, and possibly renal failure, contributed to the development of ERD. Blood pressure control and the balance of fluids are important in patients with renal failure, and may help to prevent the occurrence of ERD.

Oxidation products of zeylanidine

The oxidation of zeylanidine (1) afforded two new sesquiterpene dilactones, 4 and 5, besides two known compounds, neoliacine (2) and zeylanidinone (3). The structures of the novel oxidized products were elucidated on the basis of spectroscopic techniques, and the structure of compound 5 was further confirmed by X-ray crystallographic analysis. The mechanism for the oxidation of 1 to 4 and 5 has been postulated.

Preparation of a biphasic porous bioceramic by heating bovine cancellous bone with Na4P2O7.10H2O addition

Sintered bovine cancellous bone exhibited excellent biocompatiblity, high porosity and have an interconnecting porous structure allowing for bone ingrowth. However, the main mineral constitution of sintered bovine bone-hydroxyapatite (Ca10(PO4)6(OH)2, HAP) seems to be too stable in vivo. For improving its bioactivity, the calcined bovine bone removing the organic substance by burning process-with different quantities of sodium pyrophosphate (Na4P2O7.10H2O, NP) addition was heated to a high temperature to transform its crystalline phase constitution from HAP into TCP/HAP biphasic or other multiphasic structures. Results revealed that the calcined bovine bone without NP addition, exhibited a pure form of HAP characterized pattern during heating. Its thermal behavior was similar to stoichiometric HAP, it gradually lost its OH- ions and transformed into oxyhydroxyapatite at high temperature. After being doped into calcined bovine bone, NP would react with HAP to form betaBTCP and NaCaPO4 around 600 degrees C. At 900 degrees C, doped NP would completely react with HAP and the NaCaPO4 would further react with HAP to form more betaBTCP in the system. With NP increasing in the calcined bovine bone, HAP would gradually convert into different crystalline phase compositions of TCP/HAP, TCP/HAP/NaCaPO4 or TCP/NaCaPO4 at high temperature. By heating calcined bovine cancellouse bone with different quantities of NP we could obtain different crystalline phase compositions of natural porous bioceramic in this study.

Neurodegenerative Alzheimer-like pathology in PDAPP 717V-->F transgenic mice

In summary, PDAPP mice overexpressing a mutation associated with some cases of familial early-onset AD express several of the major pathological hallmarks associated with AD. Amyloid plaques in PDAPP mice appear quite similar to A beta deposits in AD as shown by a variety of different antibodies and stains, and are of both the diffuse and compacted varieties. Additionally, a subset of these amyloid plaques appear to be neuritic plaques. Neurodegenerative changes, including the loss of synaptic and dendritic proteins, abnormal phosphorylation of cytoskeletal elements, subcellular degenerative changes, and the deposition of lysosomal and acute phase proteins has also been seen in PDAPP mouse brains. Reactive astrocytosis and microgliosis have also been observed in association with the amyloid plaques in the PDAPP mice. No neurofibrillary tangles or paired helical filaments have been found in the mice to date. It remains unknown whether mice are capable of generating these in a manner comparable to AD in less than two years. Extensive behavioral analyses are currently being performed in these mice, and preliminary results indicate that the PDAPP mice are significantly impaired on a variety of different learning and memory tests. In conclusion, the PDAPP mouse model doesn't display all the pathological hallmarks of AD, but it does display most of them in a robust manner that increases with age and gene dosage. Therefore, this transgenic model provides evidence that alterations in APP processing and A beta production can result in AD-like neuropathology, can contribute to a mechanistic understanding of AD (since examination of AD brains yields a static view, and we are unable to view the development of various pathological changes), as well as providing an useful animal model for the testing of various therapeutic interventions directed towards specific aspects of the neurodegenerative process.

A physical map of the mouse shaker-2 region contains many of the genes commonly deleted in Smith-Magenis syndrome (del17p11.2p11.2)

We report the construction of a physical map of the region of mouse chromosome 11 that encompasses shaker-2 (sh2), a model for the human nonsyndromic deafness DFNB3. DFNB3 maps within the common deletion region of Smith-Magenis syndrome (SMS), del(17)(p11.2p11.2). Eleven of the genes mapping within the SMS common deletion region have murine homologs on the sh2 physical map. The gene order in this region is not perfectly conserved between mouse and human, a finding to be considered as we engineer a mouse model of Smith-Magenis syndrome.

DNA rearrangements on both homologues of chromosome 17 in a mildly delayed individual with a family history of autosomal dominant carpal tunnel syndrome

Disorders known to be caused by molecular and cytogenetic abnormalities of the proximal short arm of chromosome 17 include Charcot-Marie-Tooth disease type 1A (CMT1A), hereditary neuropathy with liability to pressure palsies (HNPP), Smith-Magenis syndrome (SMS), and mental retardation and congenital anomalies associated with partial duplication of 17p. We identified a patient with multifocal mononeuropathies and mild distal neuropathy, growth hormone deficiency, and mild mental retardation who was found to have a duplication of the SMS region of 17p11.2 and a deletion of the peripheral myelin protein 22 (PMP22) gene within 17p12 on the homologous chromosome. Further molecular analyses reveal that the dup(17)(p11.2p11.2) is a de novo event but that the PMP22 deletion is familial. The family members with deletions of PMP22 have abnormalities indicative of carpal tunnel syndrome, documented by electrophysiological studies prior to molecular analysis. The chromosomal duplication was shown by interphase FISH analysis to be a tandem duplication. These data indicate that familial entrapment neuropathies, such as carpal tunnel syndrome and focal ulnar neuropathy syndrome, can occur because of deletions of the PMP22 gene. The co-occurrence of the 17p11.2 duplication and the PMP22 deletion in this patient likely reflects the relatively high frequency at which these abnormalities arise and the underlying molecular characteristics of the genome in this region.

Effect of protective colloids on the induction of polymorphic changes in indomethacin agglomerates after solvent evaporation from o/w emulsions

Indomethacin (IMC) agglomerates were prepared by the solvent evaporation process from o/w emulsions containing different protective colloids in the external aqueous solution. The types of protective colloids inducing the polymorphic transformation of IMC in the agglomerates without wall material were investigated. The composition and its polymorphs were evaluated from the X-ray diffraction patterns, IR spectra and DSC thermograms. The results indicate that when pectin, beta-cyclodextrin, sodium alginate or sodium dodecyl supphase acted as a protective colloid, the respective IMC agglomerates consisted only of the alpha form of IMC. When gelatin or hydroxypropyl methylcellulose was used as a protective colloid, the amorphous, alpha and gamma forms as well as methylene chloride solvates of IMC were found in the IMC agglomerates. There was only methylene chloride solvate of IMC with a small amount of amorphous form in the IMC agglomerates prepared from albumin as a protective colloid, while IMC agglomerates prepared from methylcellulose, polyvinyl alcohol or biosoluble polymer consisted of the mixture of amorphous and alpha forms, and methylene chloride solvate of IMC. When polyvinyl pyrrolidone was applied to act as a protective colloid, the mixture of methylene chloride solvate and gamma form of IMC with less quantity of amorphous form was found in its IMC agglomerates. This strongly suggests that the composition of IMC agglomerates prepared from the solvent evaporation process was significantly influenced by the type of protective colloids used.

pH of preparations affecting the on-off drug penetration behavior through the thermo-responsive liquid crystal-embedded membrane

A liquid crystal (cholesteryl oleyl carbonate, COC)-embedded membrane with a controlled rate and higher reversibly thermo-responsive function was successfully fabricated by the vacuum filtration method. The aim of this study was to investigate the effect of the pH of aqueous solutions and gel preparations on the penetration of salbutamol sulfate through this thermo-responsive COC-embedded membrane. The results indicate that the on-off switching penetration behavior of salbutamol sulfate through the COC-embedded membrane in response to a repeatedly exchanging temperature cycle (10 <=> 25 degreesC) is not influenced by the pH of the medium. However, the pH-dependent ionization of salbutamol and the viscosity of the gel base, as well as the interaction between salbutamol and carbopol, might change the amount and the rate of salbutamol sulfate that penetrates across this COC-embedded membrane.

Preparation of high-temperature stabilized beta-tricalcium phosphate by heating deficient hydroxyapatite with Na4P2O7 x 10H2O addition

In this paper, the high-temperature stabilized beta-tricalcium phosphate (betaTCP, beta-Ca3(PO4)2) were prepared by heating the deficient HAP (d-HAP, Ca10-x(HPO4)x(PO4)6-x(OH)2-x) with tetra-sodium diphosphate decahydrate (NP, Na4P2O7 x 10H2O) addition. The betaTCP, d-HAP and d-HAP doped with 2.5, 5, 7.5 and 10 wt % NP were heated to different temperatures and were investigated by X-ray diffraction analysis (XRD) and Fourier-transformed infrared spectroscopy (FTIR). The results demonstrated that the HPO4(2-) of d-HAP condensed into P2O7(4-) occurred before 650 degrees C. The P2O7(4-) ions could be traced in the FTIR spectrum when the d-HAP was heated up to 750 degrees C. The reaction of P2O7(4-) with OH- did not occur instantly but over a wide range of temperatures. The d-HAP doped with NP would decrease the decomposition temperature of d-HAP. NP doped into d-HAP not only induced the d-HAP decomposition at lower temperature but also stabilized the betaTCP crystal structure at higher-temperature. It could also increase the conversion temperature of betaTCP to alphaTCP from 1180 degrees C up to 1300 degrees C. We could successfully prepare high-temperature (up to 1300 C) stabilized ffTCP by heating NP doped d-HAP.

Functionality of protective colloids affecting the formation, size uniformity and morphology of drug-free polylactic acid microspheres

Drug-free polylactic acid (PLA) microspheres were prepared by an emulsification-solvent evaporation technique using different types of protective colloids. The influence of five types of hydrophilic prolymers (polysaccharides, proteins, synthetic cellulose derivatives, synthetic nonionic polymers and surfactants) on the formation, size uniformity and morphology of PLA microspheres was investigated. Four characteristic functions (surface activity, viscosity, electric charge and interfacial film formation) of the hydrophilic polymer aqueous solutions were used to evaluate the efficacy of these protective colloids used. The results indicate that these four functions were the key parameters to achieve the formation of PLA microspheres. The best protective colloid should have high surface activity, optimum viscosity, adequate electric charge, and form an interfacial film to give a higher recovery, better size uniformity and smoother topography of the PLA microspheres.

Cloning, genomic structure, and expression of mouse ring finger protein gene Znf179

ZNF179, a RING finger protein encoding gene, has been mapped within the critical deletion region for Smith-Magenis syndrome (SMS), a disorder characterized by mental retardation and multiple congenital anomalies associated with del(17)(p11.2). Here we report the cloning of Znf179, the mouse homologue of ZNF179, and characterization of its gene structure. The 3028-bp cDNA has a 1.9-kb open reading frame that contains a RING finger domain at its N-terminus and an alanine-rich and glycine-rich domain at its C-terminus. Znf179 genomic sequence includes 15 introns and spans about 10 kb on mouse chromosome 11, which maintains conserved synteny with human 17p. Northern analysis indicates that Znf179 is predominantly expressed in brain and testis. Although contained within the SMS common deletion interval, FISH experiments show that ZNF179 is not deleted in two SMS patients with smaller deletions.

Genetic mapping refines DFNB3 to 17p11.2, suggests multiple alleles of DFNB3, and supports homology to the mouse model shaker-2

The nonsyndromic congenital recessive deafness gene, DFNB3, first identified in Bengkala, Bali, was mapped to a approximately 12-cM interval on chromosome 17. New short tandem repeats (STRs) and additional DNA samples were used to identify recombinants that constrain the DFNB3 interval to less, similar6 cM on 17p11.2. Affected individuals from Bengkala and affected members of a family with hereditary deafness who were from Bila, a village neighboring Bengkala, were homozygous for the same alleles for six adjacent STRs in the DFNB3 region and were heterozygous for other distal markers, thus limiting DFNB3 to an approximately 3-cM interval. Nonsyndromic deafness segregating in two unrelated consanguineous Indian families, M21 and I-1924, were also linked to the DFNB3 region. Haplotype analysis indicates that the DFNB3 mutations in the three pedigrees most likely arose independently and suggests that DFNB3 makes a significant contribution to hereditary deafness worldwide. On the basis of conserved synteny, mouse deafness mutations shaker-2 (sh2) and sh2J are proposed as models of DFNB3. Genetic mapping has refined sh2 to a 0.6-cM interval of chromosome 11. Three homologous genes map within the sh2 and DFNB3 intervals, suggesting that sh2 is the homologue of DFNB3.

Baclofen toxicity in patients with severely impaired renal function

OBJECTIVE

To report the toxic effects of baclofen in patients with severely impaired renal function.

DATA SOURCES

From 1991 to 1995, nine patients with severely impaired renal function (2 not receiving dialysis, 1 undergoing continuous ambulatory peritoneal dialysis [CAPD], and 6 receiving maintenance hemodialysis), who exhibited clinical toxicity after baclofen therapy at our hospital were included for analysis. Another seven cases from the literature obtained by computerized (MEDLINE) and manual (Index Medicus) search methods published between 1980 and 1995 were also reviewed.

INTERVENTION

Among our nine patients, the six undergoing chronic hemodialysis and one not undergoing dialysis received early (< 48 h) hemodialysis after toxic symptoms developed. The patient undergoing CAPD received late hemodialysis (> 72 h), and the other patient who had not undergone dialysis received only supportive care.

RESULTS

A review of these 16 cases revealed that most patients received only small doses and very short-term baclofen therapy. Altered consciousness was the major presenting feature. Severe acute complications, such as seizures and respiratory depression, were relatively uncommon among patients with severely impaired renal function. However, abdominal pain, which has previously rarely been reported, was noted in five of our nine patients. Most patients showed clinical improvement after hemodialysis. An analysis of these nine patients revealed that those who received early hemodialysis had a shorter recovery time than the patient who received only supportive care (2.71 +/- 0.42, respectively, vs. 9 d; p < 0.01). A lag of several hours between the end of the hemodialysis session and an improvement in the level of consciousness was noted.

DISCUSSION

As most patients with severely impaired renal function developed toxic symptoms soon after initiating a low-dose baclofen regimen, the accumulated dosage was small and severe complications were less common. Abdominal pain may have occurred as a result of the gamma-aminobutyric acid-mediated cholinergic effect exerted by baclofen. The delay in conscious recovery after hemodialysis may be due to a delay in the clearance of baclofen from the central nervous system.

CONCLUSIONS

Patients with severely impaired renal function generally develop baclofen intoxication soon after the initiation of low-dose therapy. Thus, the administration of baclofen, regardless of the dosage, in these patients is not appropriate. Abdominal pain, in addition to altered consciousness, is a common presenting feature in patients with renal failure who have baclofen intoxication. Hemodialysis is effective in alleviating the clinical symptoms and shortening the recovery time for such patients.

Homologous recombination of a flanking repeat gene cluster is a mechanism for a common contiguous gene deletion syndrome

Smith-Magenis syndrome (SMS), caused by del(17)p11.2, represents one of the most frequently observed human microdeletion syndromes. We have identified three copies of a low-copy-number repeat (SMS-REPs) located within and flanking the SMS common deletion region and show that SMS-REP represents a repeated gene cluster. We have isolated a corresponding cDNA clone that identifies a novel junction fragment from 29 unrelated SMS patients and a different-sized junction fragment from a patient with dup(17)p11.2. Our results suggest that homologous recombination of a flanking repeat gene cluster is a mechanism for this common microdeletion syndrome.

Disruption of a single allele of the nerve growth factor gene results in atrophy of basal forebrain cholinergic neurons and memory deficits

Administration of nerve growth factor (NGF) to aged or lesioned animals has been shown to reverse the atrophy of basal forebrain cholinergic neurons and ameliorate behavioral deficits. To examine the importance of endogenous NGF in the survival of basal forebrain cholinergic cells and in spatial memory, mice bearing a disruption mutation in one allele of the NGF gene were studied. Heterozygous mutant mice (ngf+/-) have reduced levels of NGF mRNA and protein within the hippocampus and were found to display significant deficits in memory acquisition and retention in the Morris water maze. The behavioral deficits observed in NGF-deficient mice were accompanied by both shrinkage and loss of septal cells expressing cholinergic markers and by a decrease in cholinergic innervation of the hippocampus. Infusions of NGF into the lateral ventricle of adult ngf+/- mice abolished the deficits on the water maze task. Prolonged exposure to NGF may be required to induce cognitive effects, because reversal of the acquisition deficit was seen after long (5 weeks) but not short (3 d) infusion. Although NGF administration did not result in any improvement in the number of septal cells labeled for choline acetyltransferase, this treatment did effectively correct the deficits in both size of cholinergic neurons and density of cholinergic innervation of the hippocampus. These findings demonstrate the importance of endogenous NGF for survival and function of basal forebrain cholinergic neurons and reveal that partial depletion of this trophic factor is associated with measurable deficits in learning and memory.

Degradation behaviour of a new bioceramic: Ca2P2O7 with addition of Na4P2O7.10H2O

A newly produced bioceramic, beta-Ca2P2O7 with addition of Na4P2O7.10H2O (SDCP), has been implanted into the femoral condyle of rabbits. Within 6 weeks after implantation, most of the bioceramic is replaced by new woven bone. On the contrary, block from hydroxyapatite (HA) and beta-tricalcium phosphate (beta-TCP), which are osteoconductible, do not resorb within a short period of time. We believe that the biodegradable behaviour of SDCP may occur in two steps. The first and most important step is the digestion of particles and migration of the particles by phagocytosis. The object of this study is to examine the change in morphologies, chemical compositions and crystal structure of SDCP after soaking in distilled water for a certain period of time. The SDCP ceramic was also co-cultured with leucocytes to observe how the SDCP particles were digested by the leucocytes, so that the mechanism of biodegradable behaviour of SDCP ceramic in vivo might be clarified. Four types of sintered calcium phosphate ceramics were tested in the experiment: SDCP, pure beta-Ca2P2O7 (DCP), HA and beta-TCP. They wee soaked in distilled water at 37 degrees C for up to 30 days. The microstructure and morphology of crystals deposited on the surface were observed using scanning electron microscopy. Sodium, calcium and phosphorus ion contents in the supernatant solution were detected by atomic absorption analysis and ion coupled plasma. In summary, HA and DCP showed no significant evidence of dissolution in distilled water. In static distilled water, calcium ions may be released from beta-TCP into solution during the initial 7 days and then converted into HA by reprecipitation. The results showed that the SDCP was firstly dissolved into small grains or fragments by the solution. The small fragments should be so small as to be digested by the phagocytes in a physiological environment.

Bioactive alkaloids from Illigera luzonensis

Using antiplatelet aggregation as a guide to fractionation, seven aporphines, actinodaphnine (1), N-methylactinodaphnine (2), launobine (3), dicentrine (4), O-methylbulbocapnine (5), hernovine (7), and bulbocapnine (9), and two oxoaporphines, dicentrinone (6) and liriodenine (8), were isolated from the stems of Illigera luzonensis. Among them, compounds 2, 4, 5, 8, and 9 were isolated for the first time from this species. Moreover, compounds 1-5, and 8 showed significant antiplatelet aggregation and compounds 1 and 6 exhibited significant vasorelaxant activities, respectively.

Genomic structure, evolution, and expression of human FLII, a gelsolin and leucine-rich-repeat family member: overlap with LLGL

The Drosophila melanogaster flightless-I gene is involved in cellularization processes in early embryogenesis and in the structural organization of indirect flight muscle. The encoded protein contains a gelsolin-like actin binding domain and an N-terminal leucine-rich repeat protein-protein interaction domain. The homologous human FLII gene encodes a 1269-residue protein with 58% amino acid sequence identity and is deleted in Smith-Magenis syndrome. We have cloned the FLII gene and determined its nucleotide sequence (14.1 kb). FLII has 29 introns, compared with 13 in Caenorhabditis elegans and 3 in D. melanogaster. The positions of several introns are conserved in FLII-related genes and in the domains and subdomains of the gelsolin-like regions giving indications of gelsolin gene family evolution. In keeping with its function in indirect flight muscle in Drosophila, the human FLII gene was most highly expressed in muscle. The FLII gene lies adjacent to LLGL, the human homologue of the D. melanogaster tumor suppressor gene lethal(2) giant larvae. The 3' end of the FLII transcript overlaps the 3' end of the LLGL transcript, and the corresponding mouse genes Fliih and Llglh also overlap. The overlap region contains poly(A) signals for both genes and is strongly conserved between human and mouse.

Reactive oxygen species are involved in nickel inhibition of DNA repair

Nickel has been shown to inhibit DNA repair in a way that may play a role in its toxicity. Since nickel treatment increases cellular reactive oxygen species (ROS), we have investigated the involvement of ROS in nickel inhibition of DNA repair. Inhibition of glutathione synthesis or catalase activity increased the enhancing effect of nickel on the cytotoxicity of ultraviolet (UV) light. Inhibition of catalase and glutathione peroxidase activities also enhanced the retardation effect of nickel on the rejoining of DNA strand breaks accumulated by hydroxyurea plus cytosine-beta-D-arabinofuranoside in UV-irradiated cells. Since DNA polymerization and ligation are involved in the DNA-break rejoining, we have investigated the effect of ROS on these two steps in an extract of Chinese hamster ovary cells. Nickel inhibition of the incorporation of (3H)dTTP into the DNase I-activated calf thymus DNA was stronger than the ligation of poly(dA) x oligo(dT), whereas H2O2 was more potent in inhibiting DNA ligation than DNA polymerization. Nickel, in the presence of H2O2, exhibited a synergistic inhibition on both DNA polymerization and ligation and caused protein fragmentation. In addition, glutathione could completely recover the inhibition by nickel or H2O2 alone but only partially recover the inhibition by nickel plus H2O2. Therefore, nickel may bind to DNA-repair enzymes and generate oxygen-free radicals to cause protein degradation in situ. This irreversible damage to the proteins involved in DNA repair, replication, recombination, and transcription could be important for the toxic effects of nickel.

Hemostatic and fibrinolytic response to desmopressin in uremic patients

Desmopressin (DDAVP) 0.3 micrograms/kg was infused in 20 uremic patients with prolong bleeding time. Prior to infusion, the uremic patients had a reduced level of tissue plasminogen activator (t-PA), normal levels of von Willebrand factor antigen (vWF:Ag) and ristocetin cofactor activity (vWF:RCo) and elevated level of factor VIII coagulant activity (FVIII:C). Patients with lower hematocrit or t-PA levels tended to have a longer bleeding time. One hour after DDAVP infusion, the bleeding time was shortened significantly. This improvement was significant in all patient groups irrespective of the high or low initial levels of factor VIII complex components. Plasma levels of FVIII:C, vWF:Ag, vWF:RCo and t-PA all increased significantly. The magnitude of increase in these factors, however, was not significantly correlated with the extent of bleeding time shortening. The multiple regression model for predicting the extent of bleeding time shortening suggested only two variables, viz initial bleeding time and posttreatment FVIII:C activity to be of significance. The present results indicate that the hemostatic response to DDAVP is uniform in uremic patients, regardless of whether the initial activities of factor VIII complex components are high or low. Posttreatment FVIII:C activity appears to play a significant role in the hemostatic action of DDAVP. Furthermore, a depressed fibrinolytic activity was generally observed to concur with the hemostatic defect in uremic patients.

Cloning, genetic mapping and expression studies of the rat Brca1 gene

The breast cancer gene BRCA1 has previously been cloned from both human and mouse. We cloned a fragment of the rat Brca1 homologue in order to map it and explore its biological function. Partial cDNA fragments of the rat Brca1 homologue were isolated by RT-PCR. Sequence analysis revealed that the RING-finger domain is well conserved among rat, mouse and human. Rat Brca1 mRNA was expressed in most tissues studied with the highest level in testis, consistent with studies in human and mouse. Next, intron 6-containing DNA fragments were amplified by PCR from WKY and WF rat strains. The splicing sites between exon 6 and exon 7 are conserved between rat and human. Partial sequencing of the rat Brca1 intron 6 revealed a polymorphism of a pentanucleotide TTTTG repeat between the WKY and WF strains. With this intragenic microsatellite marker, we were able to map precisely the rat Brca1 gene to chromosome 10 using a genetic linkage study of (WKY x WF)F1 x WF backcross rats. Brca1 cosegregates with marker BAND3A, and is flanked by R5123 and R5842. Using this polymorphic marker, we also investigated the loss of heterozygosity (LOH) of the Brca1 microsatellite marker in carcinogen- or radiation-induced mammary carcinomas in (WF x F344)F1 female rats. No LOH or somatic microsatellite instability was detected in 18 DMBA-induced tumors studied. Only one LOH of the F344 allele was observed in 26 radiation-induced tumors tested. Ribonuclease protection assays demonstrated that Brca1 mRNA levels are similar in normal rat mammary glands and mammary carcinomas of various etiologies, including those induced by DMBA, NMU, activated-neu and activated-ras oncogenes.

Permeation behavior of salbutamol sulfate through hydrophilic and hydrophobic membranes embedded by thermo-responsive cholesteryl oleyl carbonate

PURPOSE

To investigate the suitability of hydrophilic or hydrophobic membranes for use as potential thermo-responsive drug delivery system.

METHODS

Liquid crystal was embedded in membranes using vacuum filtration method to control the penetration rate of salbutamol sulfate. Cholesteryl oleyl carbonate (COC) with smectic-cholesteric phase transition temperature near 18 degrees C was used as a model liquid crystal.

RESULTS

It indicates only hydrophilic salbutamol sulfate can penetrate through the hydrophilic membranes embedded with or without COC, in which the permeation is mainly governed by the adsorption of COC. However, the hydrophilic drug do not pass through the hydrophobic membranes even if not embedded with COC. The void volume of the membrane also influences the penetration of salbutamol sulfate. The higher thermo-response efficacy of the COC-embedded membranes can be explained not only by less permeability through matrix part of the membrane but also by higher thermal motion of the COC molecules due to above the phase transition temperature.

CONCLUSIONS

A COC-embedded membrane with rate-controlled and thermo-responsive function is easily prepared by vacuum filtration method. High reversibly thermo-responsive function can be achieved by choosing membrane and COC concentration properly.

Antiplatelet of vasorelaxing actions of some benzylisoquinoline and phenanthrene alkaloids

Members of a series of benzylisoquinoline and phenanthrene alkaloids were tested for their antiplatelet and vasorelaxing actions. Atherosperminine HClO4 (15) and atherosperminium I (16) showed strong inhibition of adenosine 5'-diphosphate-induced platelet aggregation. dl-N-Methylcoclaurine (1), dl-coclaurine (6), 15, 16, xylopine hydroxylamine (18), and atherosperminine N-oxide (19) showed strong inhibition of arachidonic acid-induced platelet aggregation. Compounds 1, 15, 16, dicentrine methine (17), 18, and 19 showed strong inhibition of collagen-induced platelet aggregation. d-(-)-Magnocurarine I (8), 15, and 16 showed strong inhibition of platelet-activating factor-induced platelet aggregation. Compounds 15, 17, and 19 showed vasorelaxing action in rat thoracic aorta.

Antiplatelet and vasorelaxing actions of some aporphinoids

A series of aporphines and oxoaporphines was tested for antiplatelet and vasorelaxing actions. (+)-N-Methylactinodaphnine, (-)-norannuradhapurine x HBr, xylopine, actinodaphnine, and N-methylnandigerine showed strong inhibition of adenosine 5'-diphosphate (ADP)-induced platelet aggregation. Boldine, (+)-N-methylactinodaphnine, (-)-norannuradhapurine x HBr, xylopine, N-acetyllaurolitsine, N-methyllaurotetanine, actinodaphnine, N-methylnandigerine, O-methylbulbocapnine, and liriodenine showed strong inhibition of arachidonic acid (AA)-induced platelet aggregation. (+)-N-Methylactinodaphnine, fissoldine x HCIO4, (-)-norannuradhapurine x HBr, xlylopine, N-methyllaurotetanine, actinodaphnine, N-methylnandigerine, O-methylbulbocapnine, and liriodenine showed strong inhibiton of collagen-induced platelet aggregation. (-)-Norannuradhapurine x HBr, xylopine, N-methyllaurotetanine, and actinodaphnine showed strong inhibition of platelet-activating factor (PAF; 1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine)-induced platelet aggregation. (+)-N-Methylactinodaphnine, laurotetanine, N-methylactinodaphnine N-oxide, oxoglaucine, boldine, and actinodaphnine showed vasorelaxing action in rat thoracic aorta. The results are discussed on the basis of structure-activity relationships.

Diminution of T cells with gamma delta receptor in the peripheral blood of allergic asthmatic individuals

BACKGROUND

T cells are shown to regulate allergy and asthma. They are heterogeneous by virtue of surface receptor subtypes (alpha beta and gamma delta receptors), however, their pathophysiological roles in asthma are unclear.

OBJECTIVE AND METHODS

The present study employed flow cytometric analysis to compare the size of T-cell subsets and eosinophils present in the peripheral blood of healthy, allergic and allergic asthmatic individuals.

RESULTS

Current results demonstrated that the percentages of gamma delta T cells declined from 4.1% in healthy to 3.2% in the allergic subjects and to a significantly lower (P = 0.01) 2.4% in allergic asthmatics. The absolute numbers of circulating gamma delta T cells also were diminished in a similar fashion such that healthy individuals had a significantly higher mean cell count (91.8 x 10(3)/mL) than did allergic asthmatics (47.8 x 10(3)/mL) (P = 0.0266). In contrast, alpha beta T cells were comparable in the healthy, allergic, and allergic asthmatic populations (65.3%, 65.8% and 69.4%, respectively); the differences were not statistically significant. On a populational basis, the proportion of individuals having both gamma delta T cells < or = 4.1% and eosinophils > or = 2.1% was the lowest in the healthy population (30.8%), but was elevated in the allergic group (85.7%) as well as in the allergic asthmatic group (86.6%). However, on an individual basis, those who had reduced gamma delta T cells did not have consistently higher eosinophil counts or IgE level.

CONCLUSION

It was concluded that no significant correlation existed between the levels between gamma delta T cells and eosinophils or between gamma delta T cells and IgE present in the peripheral blood. This report, for the first time, documents that allergic asthmatics have reduced gamma delta T cells with reciprocally elevated eosinophil numbers in their peripheral circulation. However, it does not indicate that the reduction of gamma delta T cells directly correlates with the predominance of eosinophils of IgE levels in the diseased populations. The pathophysiological role of gamma delta T cells in allergic diseases awaits further exploration.

Urinary tract tuberculosis: a 10-year experience

Ninety-seven patients with urinary tract tuberculosis were reviewed from January 1983 to December 1993 at our hospital. Aside from two cases of military tuberculosis and three cases with coexisting active pulmonary tuberculosis, most urinary tract infections developed from a previous primary lung infection. Patients usually exhibited local symptoms. Fever, weight loss and anorexia were uncommon. Eighty-nine percent of the patients had abnormal urinalysis (hematuria and/or pyuria). Eight percent of the patients also had genital involvement, whereas 38% of these patients had normal intravenous pyelogram and urinalysis. Pyelograms disclosed abnormalities in 94% of the 97 patients and most revealed late changes, which were correlated with higher incidence of azotemia and anemia noted at diagnosis. Chemotherapy is the mainstay of treatment and at least three antituberculous drugs are required for initial therapy due to high drug resistance rate. Reconstructive surgery is warranted to salvage renal function. Except 6 patients run into maintenance hemodialysis, the renal functions of all patients remained stable during the period of follow-up, either receiving chemotherapy alone or combined surgery. Renal calcification may not represent inactive process, which requires further evaluation.

Pulmonary actinomycosis appearing as a "ball-in-hole" on chest radiography and bronchoscopy

A 40 year old diabetic man with pulmonary actinomycosis was admitted to hospital with recurrent haemoptysis. The chest radiograph showed an air meniscus in the left upper lobe, a rare presentation of pulmonary actinomycosis. Bronchoscopic examination revealed a mass in a cavity which has never been reported previously. He underwent lobectomy and the surgical specimen revealed sulphur granules, the typical pathological finding of actinomycosis, without evidence of fungal or mycobacterial infection.

Superinfection with hepatitis C virus in hemodialysis patients with hepatitis B surface antigenemia: its prevalence and clinical significance in Taiwan

A survey of hepatitis B surface antigen (HBSAG) and antibodies against hepatitis C virus (anti-HCV) in 173 patients undergoing hemodialysis in Taiwan revealed that 15 (9%) patients were positive for both HBSAG and anti-HCV, 106 (61%) were positive for anti-HCV alone, and 14 (8%) were positive for HBSAG alone. Most HBSAg positivity was acquired before the onset of hemodialysis. Anti-HCV positivity, however, was mainly acquired via the hemodialysis procedure. Patients with dual markers were younger (43.7 +/- 3.3 years old, p = 0.0274), had the longest period on hemodialysis (6.6 +/- 1.3 years, p < 0.001), and more severe liver dysfunction. When compared with those who were negative for both markers, patients with both HBSAG and anti-HCV had an increased incidence of chronicity (5/15 vs. 2/38; p < 0.05), ultrasonographic cirrhosis (5/15 vs. 1/38; p < 0.05), and clinical decompensation (2/15 vs. 0/38; p < 0.05). Their risk for developing ultrasonographic cirrhosis and clinical decompensation was also greater than that of patients with anti-HCV alone (5/15 vs. 8/106 and 2/15 vs. 2/106; p < 0.05 for both). The presence of HBSAG alone, however, did not increase the incidence of liver dysfunction. The presence of anti-HCV alone was only associated with a greater elevation of serum alanine aminotransferase (44.2 +/- 5.5 vs. 19.1 +/- 2.5 U/l; p < 0.05) and an increased incidence of chronicity (30/106 vs. 2/38; p < 0.05). Our results indicate that a high prevalence of HCV superinfection impose a significant risk on a large population of HBSAG-positive hemodialysis patients in Taiwan. As the coexistence of anti-HCV and HBSAG is associated with more severe liver dysfunction, it is urgent to devise effective methods to prevent HCV circulation in a hemodialysis environment-especially in a hepatitis B virus endemic area such as Taiwan.

Cloning and chromosomal localization of the rat Stat5 and Yy1 genes

Rat beta-casein gene expression is controlled in part by the positively acting factor Stat5 and the negatively acting factor Yy1. Partial cDNAs encoding the SH2 domain of rat Stat5a and Stat5b and the zinc finger domain of rat Yy1 have been cloned by an RT-PCR based approach. The nucleotide sequences encoding the SH2 domain of rat Stat5a and Stat5b are 75% homologous. The rat Yy1 cDNA is 95% homologous to its human and mouse counterparts in the zinc finger domain-encoding region. Using fluorescence in situ hybridization, we have localized Stat5a to rat chromosome band 10q32.1 and Yy1 to rat chromosome band 6q32.

Smith-Magenis syndrome deletion: a case with equivocal cytogenetic findings resolved by fluorescence in situ hybridization

The availability of markers for the 17p11.2 region has enabled the diagnosis of Smith-Magenis syndrome (SMS) by fluorescence in situ hybridization (FISH). SMS is typically associated with a discernible deletion of band 17p11.2 upon cytogenetic analysis at a resolution of 400-550 bands. We present a case that illustrates the importance of using FISH to confirm a cytogenetic diagnosis of del(17)(p11.2). Four independent cytogenetic analyses were performed with different conclusions. Results of low resolution analyses of amniocytes and peripheral blood lymphocytes were apparently normal, while high resolution analyses of peripheral blood samples in two laboratories indicated mosaicism for del(17)(p11.2). FISH clearly demonstrated a 17p deletion on one chromosome of all peripheral blood cells analyzed and ruled out mosaicism unambiguously. The deletion was undetectable by flow cytometric quantitation of chromosomal DNA content, suggesting that it is less than 2 Mb. We conclude that FISH should be used to detect the SMS deletion when routine chromosome analysis fails to detect it and to verify mosaicism.

Hepatocellular carcinoma with metastasis to right atrium--a report of three cases

Hepatocellular carcinoma (HCC) is one of the most common neoplasma in Taiwan. The tumor itself has the tendency of extension into the venous system, such as to the portal vein, hepatic vein and inferior vena cava (IVC), but intra-atrial metastasis is unusual. Antemortem diagnosis was difficult before the availability of two-dimensional echocardiography (2-DE). Sometimes, the first symptoms and signs are cardiogenic manifestations such as dyspnea on exertion, syncope, edema of the lower legs, and shock. Clinicians may mistakenly make the wrong diagnosis of heart failure. Because of this, we hereby report three cases of HCC with right intra-atrial metastasis to raise the physician's awareness. All three cases initially presented as right side heart failure. Imaging study revealed hepatocellular carcinoma with right intra-atrial metastasis. Two of the three cases died within one month after diagnosis.

Human recombinant erythropoietin and phlebotomy in the treatment of iron overload in uremic patients

Six chronic hemodialysis patients suffering from iron overload (serum ferritin ranged between 2053-15704 mu g/L) were treated with human recombinant erythropoietin (EPO) alone for eighteen months. An initial rapid decrease of serum ferritin was observed in all six patients when the loading dose of EPO was given. Three patients (Cases 4, 5, 6) who suffered from chronic blood loss maintained a continuous decline of serum ferritin in the subsequent stage of maintenance dose EPO therapy, however, the decrease of serum ferritin became sluggish under a maintenance dose in the other three patients (Cases 1, 2 and 3). The serum ferritin eventually decreased to a satisfactory level (975-1761 mu g/L) in Cases 4, 5 and 6, whereas it remained high (4232-8196 mu g/L) in Cases 1, 2, and 3 who had higher basal levels of serum ferritin (5641-15704 mu g/L) and a plateau of response under a maintenance dose of EPO. These three patients were then treated with EPO and phlebotomy. Their serum ferritin decreased quickly from 6752 +/- 1264 mu g/L to 2454 +/- 482 mu g/L after six months of phlebotomy therapy; it was a dramatic improvement in contrast to the stagnant response under a maintenance dose of EPO alone. Our experience indicates that EPO therapy alone has its limitations in treating severe iron overload. Although there is an initial rapid decrease of serum ferritin during the period of the loading dose, the response might become stagnant during the period of maintenance dose. Phlebotomy effectively eliminated the excessive iron stores in these refractory cases. Therefore, we suggest that phlebotomy be considered in severe iron overload if a stagnant response is observed under a maintenance dose EPO therapy.

Synaptic loss in cognitively impaired aged rats is ameliorated by chronic human nerve growth factor infusion

In the present study, we assessed the synaptic changes in aged impaired and unimpaired rats, and the effect of exogenous human nerve growth factor administration on behavioral activity and synaptic density. Human nerve growth factor was administered into the rat ventricles with a cannula connected to an osmotic pump in adult, aged impaired and unimpaired rats. Behavioral performance was evaluated in the Morris water maze. Aged impaired rats had an 18 +/- 4% decrease in the number of synaptophysinimmunoreactive presynaptic terminals as compared to aged unimpaired rats. After a continuous four-week human nerve growth factor, the aged impaired rats displayed a significant 16 +/- 3% increase in the number of synaptophysin-immunoreactive presynaptic terminals in the frontal cortex, as compared to aged impaired rats treated with vehicle. This increase correlated with an improvement in water maze performance (r = -0.74, P < 0.001). Measurements of synaptophysin-immunoreactive presynaptic terminals in other cortical and subcortical regions did not show any statistically significant difference or correlations among the various groups. These results support the possibility that nerve growth factor mediates the induction of other trophic factors which, in turn, might potentially produce a sprouting response of non-cholinergic fibers that ameliorate the cognitive deficits in impaired, aged rats.

Cloning of the human 1 alpha,25-dihydroxyvitamin D-3 24-hydroxylase gene promoter and identification of two vitamin D-responsive elements

A genomic DNA clone for 1 alpha,25-dihydroxyvitamin D-3 (1,25-(OH)2D3) 24-hydroxylase was isolated from a human chromosome 20 library. It spans 2.42 kb, containing the first two exons, the first and part of the second introns, and a 1.26 kb 5'-flanking region. Putative transcription cis-elements were revealed throughout the 5'-flanking region, including TATA box, CAAT box, GC boxes, vitamin D-responsive elements (VDRE), AP1, and AP2 sites. In a CAT reporter gene expression assay, the 24-hydroxylase promoter with its 1.2 kb 5'-flanking sequence elicits a 1,25-(OH)2D3-induced transactivation activity. Gel mobility shift assays of those putative DREs have identified that two different elements can form specific complexes with porcine intestinal nuclear extract (PINE). The specificity of VDRE-PINE complexes was verified by supershift assay with VDR-specific monoclonal antibody VXIE10B6. The proximal element VDREp (-172/-143) consists of three direct repeat half-sites, GAGTCAgcgAGGTGAgcgAGGGCG, in anti-sense orientation. The distal element VDREd (-293/-273) consists of two direct repeat half-sites, GCGTTCaccGGGTGT, also in anti-sense orientation. Both VDREs can direct a reporter gene expression using a heterologous herpes simplex virus thymidine kinase (TK) promoter in a 1,25-(OH)2D3-dependent fashion. Further characterization of these VDREs in various constructs with either a native or TK promoter suggests that both VDREs are required for the optimal induction of 24-hydroxylase expression by 1,25-(OH)2D3.

Urologic cancers in uremic patients

From 1981 through 1990, 21 urologic cancer cases were discovered in 21 uremic patients at our hospital. This constituted 55% (11 of 20) of the total malignancies in nondialyzed uremic patients, 41% (nine of 22) of the total in chronic hemodialysis patients, and 50% (one of two) of those in patients on continuous ambulatory peritoneal dialysis. No cases of urologic cancer were found in kidney transplant recipients. When compared with the general population, the standardized incidence ratio of kidney cancer in chronic hemodialysis patients was found to be 24.1 (P < 0.01) and that of bladder cancer was found to be 16.4 (P < 0.01). Multiple underlying renal diseases contributed to the development of the urologic cancer cases, including four analgesic nephropathy-associated transitional cell carcinoma cases, two acquired cystic kidney disease-associated renal cell carcinoma cases, two chronic pyelonephritis-associated (stone and tuberculosis) squamous cell carcinoma cases, and one xanthogranulomatous pyelonephritis-associated transitional cell carcinoma case. Uremia per se may be an important promoting factor. Hematuria (17 of 21 cases) was the most common presenting feature despite the fact that most of the patients were anuric. The clinical diagnosis of renal parenchymal tumors was based on ultrasonography (five of five cases), whereas most urothelial tumors were detected by cystoscopy or retrograde pyelography (14 of 16 cases). The survival rate of the 17 aggressively treated patients was 82% at 2 years and 45% at 5 years. We conclude that uremic patients are at greater risk of developing urologic cancer.(ABSTRACT TRUNCATED AT 250 WORDS)

[A study on sex hormones in gingival crevicular fluid and black pigmented bacteria in subgingival plaque of pregnant women]

Gingivitis is one of the most common oral diseases. It is caused by dental plaque and by the factors produced/released from it. The black pigmented bacteria in subgingival dental plaque are thought to be the periodontopathogens. Prevotella intermedia and Porphyromonas gingivalis have been shown to be closely associated with human gingivitis. Prevetella intermedia can use female sex hormones such as progesterone or estradiol as a source of nutrients. In pregnant women, the concentrations of progesterone and estradiol are markedly increased in serum and both are accumulated and found in the gingival tissue. The purpose of this study was to test levels of female sex hormones in gingival crevicular fluid and to observe the relationship between hormones and black pigmented bacteria in subgingival plaque. The results showed that the amount of progesterone found in the gingival crevicular fluid and percentage of black pigmented bacteria in subgingival plaque of pregnant women were markedly higher than in the postpartum stage. The percentage of black pigmented bacteria was positively correlated with the progesterone level, pregnancy and the severity of the gingivitis. Severity of the gingivitis was positively correlated with both the plaque index and the percentage of black pigmented bacteria in subgingival plaque.

Somatic gene transfer of NGF to the aged brain: behavioral and morphological amelioration

Primary fibroblasts modified to secrete nerve growth factor (NGF) were implanted into the nucleus basalis magnocellularis (NBM) of aged memory impaired rats. The NGF-producing fibroblasts survived for 6 weeks following transplantation and continued expressing NGF mRNA through the duration of the experiment. A significant amelioration of the memory impairment and a significant increase in size and number of low-affinity NGF receptor (p75)-positive neurons in the basal forebrain were observed. Implantation of NGF-producing cells into normal young adult rats resulted in a transient but significant memory impairment and hypertrophy of low-affinity NGF receptor-positive neurons. These results show that naturally occurring age-related memory loss can be reversed by grafting cells engineered to secrete NGF directly to the NBM, and that either cholinergic hyper- or hypofunction may lead to cognitive impairments.

Induction and relief of nasal congestion in ferrets infected with influenza virus

Susceptible ferrets intranasally infected with influenza virus consistently responded with maximal nasal secretion of virus, febrile reaction, and influx of inflammatory cells into nasal lumen on day 2 post infection (d.p.i.). Polymorphonuclear leucocytes were the earliest predominant cell, followed by monocytes/macrophages while lymphocytes were maintained as a minor population throughout the 7-day period. Nasal congestion level, continuously monitored by computer aided active anterior rhinomanometry, was reproducibly maximal at 2 d.p.i., diminished in intensity the next day and returned to the basal level within 7 d.p.i. Nasal congestion was effectively relieved by a single intranasal dose of 0.1% oxymetazoline or 0.2% phenylephrine, or a single intragastric administration of pseudoephedrine. Intranasal delivery of a single dose of 1% pyrilamine relieved nasal congestion while 0.8% ipratropium bromide and 30% cimetidine were ineffective. These results suggested that nasal congestion is regulated by alpha-adrenergic receptors in the mucosal vasculature or by H1 histamine receptor, but is unaffected by inhibitors of nasal secretion regulated by the cholinergic nervous system. The present study indicates that the infectious rhinitis ferret model provides a reproducible nasal congestion pattern that can be objectively measured by a refined active anterior rhinomanometric system. This labour intensive measurement, however, makes it difficult either to conduct a large population animal study or to use it for a rapid throughput screening of new drugs. The temporal relation between the influx of inflammatory cells into the nasal lumen and the onset of nasal congestion underlies the model's relevance to the exploration of the pathogenic mechanism(s) during viral rhinitis.