FRAXAC1 and DXS548 polymorphisms in the Chinese population

The fragile X syndrome is the most common inherited form of mental retardation. Haplotype studies using FRAXAC1 and DXS548 polymorphic markers flanking the fragile site have demonstrated linkage disequilibrium at the FMR1 locus. We investigated the association of the FRAXAC1, DXS548 and CGG alleles between normal subjects and mentally retarded (MR) patients of unspecified cause who do have fragile X syndrome. We have evaluated the FRAXAC1 site in 390 normal subjects and 321 MR patients and the DXS548 site in 146 normal and 319 MR subjects. Both FRAXAC1 and DXS548 alleles were determined by application of the polymerase chain reaction. When compared with Caucasians, the normal Chinese population has a different FRAXAC1 allele distribution. There are more AC18 repeat alleles and fewer AC19 repeat alleles. The DXS548 allele distributions were similar between Chinese and Caucasians. The same distribution pattern of FRAXAC1 alleles was found in both normal subjects and MR patients, but there were significant differences in the distribution patterns of DXS548 alleles. The FMR1 CGG-DXS548 and FRAXAC1-DXS548 haplotype distribution between normal subjects and MR patients also differed significantly. Our results suggest a possible association between DXS548 alleles and non-FRAXA mental retardation.

Reduced mRNA for G3BP in fragile X cells: evidence of FMR1 gene regulation

Although fragile X syndrome is caused by the absence of fragile X gene expression, little is known about the pathogenic processes underlying the mental retardation. Recent findings that the fragile X protein, FMRP, contains RNA binding motifs and nuclear transport signals and associates with ribosomes suggest that FMRP may be involved in either mRNA processing, transport, or translation. To test the hypothesis that absence of FMRP may affect the processing of specific transcripts, we have used an RNA differential display assay (RDDA) to identify differentially expressed transcripts in lymphoblast lines derived from fragile X syndrome patients. A 0.9-kb cDNA fragment that showed reduced expression in a fragile X lymphoblast cell line was found to be identical to G3BP (Ras-GTPase-Activating protein SH3-domain-binding protein). Quantitative reverse transcriptase-polymerase chain reaction showed that the expressed levels of G3BP mRNA in fragile X lymphoblast cell lines were significantly less than controls. Our results indicate that G3BP mRNA may be regulated by FMRP and supports the hypothesis that FMRP may modulate the transcription of specific transcripts.

[Effect of antisense oligonucleotides on endothelin converting enzyme expression and endothlin-1 release from airway smooth muscle cells]

OBJECTIVE

To explore the mechanism of TNF-alpha induced ET-1 release and evaluate the effects of endothelin converting enzyme (ECE) antisense oligonucleotides (oDNS) on TNF-alpha induced ET-1 release from airway smooth muscle cells (ASMC).

METHODS

ASMC transfected with the antisense oligonucleodides of ECE vectored with lipofectin were established. TNF-alpha induced ECE-mRNA expression and ET-1 release from above cultured cells were determined by RT-PCR and ELISA.

RESULTS

ET-1 levels (10.1 +/- 0.3) ng/L and ECE expression (ECE/beta-actin: 0.228 +/- 0.015) in cultured ASMC incubated with 1,000 U/ml TNF-alpha were significantly higher than those in controls without TNF-alpha incubation (7.3 +/- 0.8) ng/L, (0.132 +/- 0.032, all P < 0.01). However, after transfecting antisence ECE-oDNS in those cells, ET-1 levels and ECE expressions were significantly lower than those in control cells without antisense transfection. The inhibition rates were (29 +/- 5)% and (35 +/- 12)% respectively.

CONCLUSIONS

Abnormal expression of ECE mRNA may be a keypoint responsible for TNF-alpha induced ET-1 release in human ASMC; TNF-alpha induced ET-1 release and ECE mRNA expression from human ASMC are inhibited by antisense oligonucleotide of ECE.

Accelerated prenatal diagnosis of fragile X syndrome by polymerase chain reaction restriction fragment detection

Prenatal diagnosis of fragile X syndrome requires detection of the full FMR1 mutation in chorionic villus or amniotic fluid cell samples. Although analysis of genomic DNA restriction fragment pattern is a highly reliable technique for identification of the full FMR1 mutation, standard Southern blot determination of this pattern requires significantly more genomic DNA than is initially available from a prenatal sample. To overcome this limitation we developed a method that determines the diagnostic pattern of genomic restriction fragments from a fraction of a prenatal specimen. The prenatal DNA sample is first digested with EcoRI and EagI, and after agarose gel electrophoresis, the 2- to 10-kb region of the gel is serially sectioned and amplified by polymerase chain reaction. Analysis of prenatal samples from an unaffected male and from a full mutation male showed that this approach generated a diagnostic pattern comparable with a Southern blot of 100-fold more material. This innovation enables laboratories to prenatally diagnose the full FMR1 mutation sooner than standard techniques.

Prenatal fragile X detection using cytoplasmic and nuclear-specific monoclonal antibodies

We have been carrying out studies aimed at improving prenatal detection of the fragile X chromosome/mutation. Our current protocol requires a turnaround time (TAT) of several days. In an attempt to reduce the TAT, we have turned to the use of monoclonal antibodies (mAbs). Monoclonal antibody 1A1 (provided by Dr. Mandel of INSERM) immunostaining was performed according to a modified three-step immunocytochemical procedure. We found that cytoplasmic staining intensities, using mAb 1A1/avidin biotinylated complex/diaminobenzidine, varied from light to heavy within each sample, with controls exhibiting a majority of heavily stained cells in both chorionic villus (CV) sample and amniotic fluid cultured cells. Using mAb 1A1 and a new nuclear-specific antibody, mAb 3F11, we found that CV cultured cells harboring the FMR1 full mutation could be distinguished from controls as early as 10 weeks of gestation in both male and female specimens. Western blot analysis showed that the antibodies have similar staining patterns but that mAb 3F11 has fewer background/nonspecific bands. Our results demonstrate that it is feasible to detect fragile X full mutations within one day after obtaining cells from CV specimens taken as early as 10 weeks of gestation.

[TCD functional test for vertigo induced by ischemic cerebrovascular disorders]

OBJECTIVE

To diagnose differentially the vetigo induced by some ischemic cerebrovascular disorder.

METHOD

Patients with vertebrobasilar artery transient ischemic vertigo (group A), migraine (group B), hyperventilation syndrome (group C), hypertension (group D) are measured by using TCD functional examination which included blood peak velocity of systolic (Vs) and diastolic (Vd) end-period of vertibrobasilar artery of routine TCD (TCD-R), one minute hyperventilation TCD (TCD-HV) and one minute voluntary apnea TCD (TCD-B) respectively.

RESULT

It showed that the Vs, Vd are decreased under the three conditions in A, B and D groups. The most apparent decrease are obversed in D group. The values of the decrease are similar between group A and B. No changes are found in C group. The abnormal Vs incidences of TCD-B measurement in group A are higher than those in group B and C, but significant lower than those in group D; and in TCD-HV test lower than group D and C, higher than group B; in TCD-R test, lower than group D, and no difference with group B and C. The abnormal incidences of Vd in group A are lower than group D and higher than group B in TCD-B test. In TCD-HV test, the group A abnormol incidences are lower than group D but higher than group B and C. In TCD-R test, the abnormal incidences are lower than group D and no difference between group B and C.

CONCLUSION

The TCD measuremen is useful for differential diagnosis of vertigo induced by ischemic cerebrovascular disorders.

5-HTTLPR variants not associated with autistic spectrum disorders

To determine whether there is an association of polymorphic variants of the serotonin transporter (5-HTT) gene-linked polymorphic region (5-HTTLPR) and autistic spectrum disorders, we analyzed the 5-HTTLPR genotypes of 72 autistic subjects, 11 fragile X syndrome patients with autistic behavior, 43 normal subjects, and 49 fragile X syndrome non-autistic subjects. The distribution frequency of 5-HTTLPR long allele (L) and the short allele (S) variants showed no differences between subjects. Our findings do not support the hypothesis that polymorphic 5-HTTLPR variants are a susceptibility factor for autistic disorders.

Reevaluation of neuronal ceroid lipofuscinoses: atypical juvenile onset may be the result of CLN2 mutations

This study describes the phenotype/genotype analyses of 56 probands with a juvenile onset, some of which had atypical features of neuronal ceroid lipofuscinosis, collected at the New York State Institute for Basic Research (IBR). In this group, we found probands with abundant curvilinear profiles in lysosomal storage material, deficiency of pepstatin-insensitive peptidase, and mutations in the CLN2 gene, as well as patients with a predominance of granular osmiophilic deposits in the lysosomal storage material, deficiency of palmitoyl-protein thioesterase, and mutations in the CLN1 gene. We have divided the probands into two categories: typical (or classic) and atypical. Most of the typical and atypical probands had onset of symptoms about or after 4 years of age. Interfamiliar and intrafamiliar variations were found, especially in the speed of becoming practically blind. Thus, our study indicates that some mutations in the CLN1, CLN2, and CLN3 genes may be associated with late onset of the disease process, may have a more benign clinical course, and clinic overlap with other forms of neuronal ceroid lipofuscinosis.

[The influence of short-term pure tone exposure on amplitude of distortion-product otoacoustic emissions and spectral history]

OBJECTIVE

To observe the changs of the amplitude and the spectral history of DPOAE in the slightly damaged cochlea.

METHOD

Fifteen of young person with normal hearing were exposed to 4 kHz short-term pure tone (Level = 130 dB SPL) for 3 minutes to analysis the change of DPOAE in details after Temporary Threshold Shift (TTS).

RESULT

The comparison of pre- and postexposure showed that the thresholds of sound reflex is 9.78 +/- 6.98, 8.04 +/- 5.58, 13.0 +/- 5.58 dB HL and 8.82 +/- 6.23, 5.75 +/- 4.42, 9.05 +/- 2.27 dB HL in 0.5, 1, 2 kHz, respectively. The amplitude of DPOAE decreased 4.28 dB SPL in 6 kHz, and the spectral history rippled significantly. The coefficience of variance is 5.18 +/- 1.63%. The combination of the amplitude and the coefficience of variance indicated that 80.0% of those is abnormal.

CONCLUSION

The results confirmed that the spectral history of DPOAE is a sensible tool to assess the slightly cochlear lesion together with the amplitude of DPOAE.

[Clinical value of distortion product otoacoustic emission (DPOAE) and their contralateral suppression effects]

OBJECTIVE

The present paper aimed at examining the role of DPOAE and their contralateral suppressive effects in evaluation medial olivocochlear system (MOCS) function status in human.

METHOD

Seventeen subjects (34 ears) with normal hearing, 13 ears with cochlear hearing loss and 9 ears with retrocochlear hearing loss were studied on their DPOAE and contralateral suppression.

RESULT

The results revealed that DPOAE amplitude significantly reduced in ears with cochlear hearing loss, contralateral suppression was smaller than normal ears but there was no significant difference between two groups. By contrast, DPOAE amplitude was much higher in ears with retrocochlear hearing loss than that in the other two groups. Contralateral suppression was significantly reduced or disappeared, and contralateral acoustic stimulus (CAS) even increased DPOAE amplitude in ears with retrocochlear hearing loss.

CONCLUSION

DPOAE and suppression induced by CAS can be used as an index of medial olivocochlear system (MOCS) function in patients with sensori-neuaral hearing loss, and can differentiate cochlear hearing loss from retrocochlear hearing loss. The tests of DPOAE and contralateral suppression may have much more advantages in clinical application over any other audiological test.

[A study on DPOAE in patients with diabetes mellitus]

In present experiment we tested DPOAE in 19 patients with diabetes mellitus and compared with control subjects. Results showed that DPOAE (f2 above 3 kHz) disappeared in 2 patients (3 ears) indicating cochlear lesion, both of DPOAE contralateral suppressive effects and selective attention effects significantly reduced in 4 patients (7 ears), and reversed in 3 patients (6 ears) indicating disorders existing in cortex topdown and efferent of MOCS. It was suggested that tests of DPOAE and suppression (induced by CAS and selective attention) may be useful for making early diagnosis of cochlear-pathy and auditory efferent disorders (cortex and MOCS) before retinalpathy happened. This study on DPOAE provided important evidence for early diagnosis and early treatment of diabetic complications.

[The changes of EG1 and EG2 positive eosinophils and their clinical significance in asthmatics]

OBJECTIVE

To evaluate the significance of EG1 or EG2 positive eosinophils in relating to the severity of asthma.

METHOD

EDTA-anticoagulated venous blood were treated by FOG method, and FTTC-conjugated monoclonal antibodies were added. Flow cytometry technique was used.

RESULT

EG1 and EG2 positive eosinophils increased significantly in patients with acute asthma (n = 29) as compared with control (n = 13) and COPD (n = 12), P < 0.05. There were significant correlation of the mean fluorescence intensity(MFI) between EG1, EG2 and the degree of the symptom.

CONCLUSION

There is a significant increase of activated eosinophils in peripheral blood in asthmatics, the expression of EG1 and EG2 positive eosinophils correlated well with the severity of symptom in asthmatics. EG1 and EG2, as the marker for eosinophils activity, may be sensitive and specific in evaluating the severity of asthmatics symptom.

Two common mutations in the CLN2 gene underlie late infantile neuronal ceroid lipofuscinosis

Late infantile neuronal ceroid lipofuscinosis (LINCL) is one of the most common pediatric neuronal degenerative disorders. A candidate gene underlying this disease, designated CLN2, was recently cloned and the gene product was characterized as a lysosomal pepstatin-insensitive carboxypeptidase (LPIC). Four mutations were identified in CLN2 from three unrelated LINCL individuals. To investigate further the mutation frequency in LINCL, we screened 16 LINCL probands for these four mutations. The previously reported intronic mutation, T523-1 G-->C. was found in 56% (9/16) of the cases, of which two were homozygous and accounted for 34% (11/32) of LINCL chromosomes. The previously reported nonsense mutation, 636 C-->T leading to R208stop, was found in 31% (5/16) of the cases, including one homozygote and accounted for 19% (6/32) of LINCL chromosomes. Two previously described missense mutations, 1107 T-->C and 1108 G-->A, were not detected in any of these 16 probands. In total, the two observed mutations, T523-1 G-->C and 636 C-->T, accounted for 53% (17/32) of LINCL alleles. Thus, one or both mutations were seen in 11 (69%) cases and no mutation has yet been identified in five. Our finding that these two mutations are common in LINCL cases adds further evidence in support of the idea that dysfunction of LPIC underlies LINCL. Positive molecular testing can now complement clinical diagnosis of LPIC and will allow for pre-natal diagnosis for subsequent pregnancies.

[Effect of inhaled-corticosteroids on the mRNA expressions of endothelin-1 and endothelin converting enzyme in bronchial asthma]

OBJECTIVE

To investigate the expressions of endothelin-1(ET-1) and endothelin converting enzyme (ECE) mRNA in bronchial mucosal biopsis from asthmatics, and the effect of inhaled-corticosteroids on the expressions of ET-1 and ECE genes.

METHOD

The expressions of ET-1 and ECEmRNA in bronchial mucosal tissue were evaluated by reverse transcription DNA polymerase chain reaction (RT-PCR); With fibro bronchoscopy, the naked-eye inflammatory severity and inflammatory score of bronchial mucoses were recorded.

RESULT

(1) The expression level of ET-1 mRNA was 0.86 +/- 0.06 in non-steroids-treated group and 0.14 +/- 0.06 in control non-asthmatic group. The expression of ECE mRNA in non-steroid group was 0.31 +/- 0.04, and 0.30 +/- 0.05 in control group, P = 0.238. (2) The ET-1 and ECE mRNA expressions were 0.22 +/- 0.01 and 0.16 +/- 0.01 respectively in steroid treated group. (3) The naked-eye bronchial mucosal inflammatory score was 6.0 +/- 1.9 in non-steroids treated group, moreover, the expression of ET-1 mRNA was positively correlated with the score (r = 0.78, P < 0.05).

CONCLUSION

There was markedly higher ET-1 mRNA expression in the bronchial mucosa in asthmatics, but the ECE mRNA expression was unchanged significantly; Inhaled corticosteroids obviously inhibited both ET-1 mRNA and ECE mRNA expressions in bronchial mucosa, which may be one of the anti-inflammatory mechanisms of inhaled-corticosteroid in management of bronchial asthma.

[Analysis of spectral history of distort-product otoacoustic emissions in subjects of transient vertebrobasilar ischemic vertigo]

Analysis of the spectral history of distrot-product otoacoustic emissions (DPOAE) was performed to evaluate the cochlear function in subjects of vertebrobasilar transient ischemic vertigo (VBTIV). Thresholds of pure tone and acoustic reflex didn't increase while the amplitudes of DPOAE decreased, and the spectral history of DPOAE rippled dramastically. 36.8% of cases were found abnormal by the amplitudes and the spectral history of DPOAE. The results confirmed that those patients with mild disfunction of cochlea can be detected by the amplitude and spectral history of DPOAE, which may be useful to differentiate the region of VBTIV.

[Thoracoscopic lung reduction surgery for emphysema]

OBJECTIVE

To study the surgical treatment of emphysema.

METHOD

Five patients with severe diffused pulmonary emphysema underwent surgical bilateral lung volume reduction by video-assisted thoracoscopy. All patients were male and their age ranged from 60 to 71 years (mean 64.3 years). Before surgery, 5 patients required supplement oxygen with exertion and one oxygen supplement at rest. Preoperative and postoperative assessments included standard pulmonary function studies, chest CT scan and quantitative nuclear lung perfusion and ventilation scan. Wedge resection was performed were in 3 patients, simple plication in 1, and combined wedge resection and plication in 1. There were no early or late mortality and no requirement for immediate postoperative ventilatory assistance.

RESULT

Follow-up ranged from 10 to 12 months. After surgery the mean forced expiratory volume in 1 second (FEV(1)) was significantly increased from 0.46 L to 1.13 L (P < 0.001) and the mean forced vital capacity (FVC) was markedly improved from 1.74 L to 2.93 L (P < 0.001). Pulmonary compliance was significantly improved and resistance of airway decreased (P < 0.001). The mean distance during 6-min walk test increased from 10 m to 400 m in 4 patients.

CONCLUSION

Thoracoscopic bilateral lung volume reduction is an effective and safe technique for patients with severe emphysema. It can relieve dyspnea and improve in excise tolerance and quality of life.

[L-arginine prolonged the efficacy of inhaled nitric oxide on the inhibition of pulmonary hypertension]

OBJECTIVE

The aim of this study is to investigate the effects of L-arginine, the substrate of nitric oxide (NO) on the duration of nitric oxide selective decrease of pulmonary hypertension. To assess whether combined use of inhaled nitric oxide and venous administered L-arginine can improve the efficacy of inhaled NO on the inhibition of hypoxia induced pulmonary hypertension.

METHOD

Eight pigs with hypoxic pulmonary hypertension received either inhaled NO(12-15 ppm) for 10 minutes or inhaled NO plus venous administrered L-arginine(10 g), then hemodynamic parameters were recorded.

RESULT

NO inhalation significantly inhibited hypoxic induced pulmonary hypertension with pulmonary arterial pressure decreasing from 4.2 +/- 0.4 kPa to 2.5 +/- 0.5 kPa(P < 0.01) and pulmonary vascular resistance from 56 +/- 25 kPa.s.L-1 to 31 +/- 13 kPa.s.L-1(P < 0.01), but this just lasted for 3-5 minutes after stopping inhalation; combined use of L-arginine infusion did not further decrease pulmonary arterial pressure, but significantly prolonged the inhibitory effect of inhaled NO on pulmonary hypertension (20 times) as compared with inhaled NO only.

CONCLUSION

With the existence of exogenous NO, supplement of NO substrate L-arginine produced a synesgetic inhibition effect on hypoxic induced pulmonary hypertension.

[Determination of normal values and analysis of their relation for distortion product otoacoustic emission in guinea pigs]

In the present paper, we measured systematically the normal values of 1, 2, 4, 6 kHz distortion product otoacoustic emission (DPOAE) in guinea pigs and analyzed the relation of these values. The incidence of DPOAE in all frequencies were 100%. The amplitudes of DPOAE above 2 kHz were large than 25 dB SPL, but the amplitude of 1 kHz was lower than one of above 2 kHz. The threshold of above 2 kHz were lower than one of 1 kHz. A trend was found that latencies of all frequencies decreases accompanied with the f2 frequencies increasing. I/0 function curves demonstrated that there was a significant relation between the amplitudes of DPOAE and the levels of primary stimuli in the statistics, that is, lower levels of primary stimuli and smaller amplitudes of DPOAE. Our results indicated that a guinea pig, whose DPOAE possessed the properties of high incidence, large amplitude and stable responsibility, was an appropriate experimental animal for studying DPOAE. In addition, this paper recommended briefly the experience about the measuring techniques for DPOAE in guinea pigs.

Molecular screening of Batten disease: identification of a missense mutation (E295K) in the CLN3 gene

Batten disease, the juvenile form of neuronal ceroid lipofuscinosis, is a prevalent neuron degenerative disorder of childhood. A 1.02-kb genomic deletion in the Batten disease gene CLN3 has been determined to be a common mutation. We developed a PCR method to screen for this deletion and tested 43 Batten disease probands. We found 36% (31/86) of Batten disease chromosomes did not carry the 1.02-kb deletion. Of the three heterozygotes for the 1.02-kb deletion, a novel G-to-A missense mutation at nucleotide 1020 of the CLN3 cDNA sequence was found on two of the non-1.02-kb deletion chromosomes. The missense mutation resulted in a substitution of glutamic acid (E) by lysine (K) at position 295 (E295 K). The E295 K mutation causes a change in predicted local protein conformation. This glutamic acid is a highly conserved acidic amino acid, being present in human, mouse, dog and yeast, which suggests it may play an important role in the function of the Batten disease protein.

Studies of atypical JNCL suggest overlapping with other NCL forms

In the United States, juvenile neuronal ceroid-lipofuscinosis (JNCL) is the most common form of NCL. This study analyzed 191 cases, diagnosed on the basis of age-at-onset, clinical symptomatology, and pathologic findings. Twenty percent (40/191) of these cases from 24/120 families manifested atypical clinical symptomatology and/or pathologic findings (typical revealed fingerprints and atypical revealed mixed inclusions, or only curvilinear or granular profiles) and, therefore, represent variant forms of JNCL. Those patients in the study with typical JNCL were a uniform group of cases, whereas the atypical were heterogenous and were divided into 8 subgroups based on the clinicopathologic findings. Forty-three families were analyzed (27 typical, 16 atypical) for the common 1.02 kb deletion and several pedigrees for novel mutations. In typical JNCL the common 1.02 kb deletion in both alleles (homozygous) were observed in 23/27, and only 1 allele (heterozygous) was exhibited in 4/27 families. In atypical JNCL families, 5/16 were heterozygous for the common 1.02 kb deletion. None of the remaining 11/16 families had the common 1.02 kb deletion in either allele, but in 9/11 cases the palmitoyl-protein thioesterase (PPT) levels were deficient. In cases where the mutation in CLN3 gene has not been identified, several possibilities may exist. The phenotype may be caused by a yet undefined mutation in CLN3 or may be due to overlapping with other forms of NCL.

[Prophylactic and therapeutic effects of beclomethasone inhalation on bronchial hyperresponsiveness and asthma: a randomized, double-blind, parallel-group controlled trial]

OBJECTIVE

To better understand the effects of corticosteroid inhalation on asthma and asymptomatic bronchial hyperresponsiveness (BHR).

METHODS

A double blind, randomized study was conducted to compare the effects of beclomethasone dry powder (BDP, 600 micrograms/day) inhalation with placebo on BHR and asthmatic symptoms in 59 students (12-18 yrs) for one year.

RESULTS

After one year of treatment, lgPD20-FEV1 increased significantly in asthmatics in the BDP group (0.385 +/- 0.424 vs 1.187 +/- 0.603 mumol histamine). Thirty percent of asthmatics in BDP group and 86% in the control group developed symptoms in this year (P = 0.076). There was no significant difference in lgPD20-FEV1 between the BDP and the control group in asymptomatic BHR students. However, none in the BDP group of asymptomatic BHR students developed asthmatic symptoms compared with 3 cases (15%) in control group. The accumulative symptom score showed significant difference between the BDP group and the control group in asymptomatic BHR students (1.50 +/- 2.54 vs 5.58 +/- 6.22, P < 0.01).

CONCLUSION

The results suggested that BDP could significantly relieve the severity of BHR and symptoms in asthmatics, and could have some prophylactic effects on the development of asthma in those with asymptomatic BHR.

Compound heterozygous genotype is associated with protracted juvenile neuronal ceroid lipofuscinosis

We present a clinicopathological study and the first molecular genetic analysis of a family with 2 siblings affected by a rare, protracted form of juvenile neuronal ceroid lipofuscinosis (JNCL). Molecular genetic studies showed that both siblings, in addition to being heterozygous for the 1.02-kb CLN3 deletion, a common mutation in JNCL, also had a G-to-A missense mutation at nucleotide 1,020 of the CLN3 cDNA sequence on the non-1.02-kb deletion chromosomes. This point mutation resulted in a substitution of glutamic acid by lysine at position 295 of the CLN3 protein. Thus, a single point mutation at residue 295 of the CLN3 protein in protracted JNCL may underlie the phenotype in this form, which differs from that in classic JNCL.

[Effects of selective attention on distortion product otoacoustic emissions]

To investigate the effects of upper central nervous system on cochlear micromechanics, distortion product otoacoustic emissions (DPOAE) with and without a visual attention task were studied in 16 young subjects with normal hearing. The results showed that the DPOAE (2f1-f2) amplitude were reduced, and significantly decreased in 1 kHz and 2 kHz of F2. In the underlying mechanism of the effects, it is possible that the upper central nervous system facilitate the olivocochlear efferent system and then modulate the cochlear functions. It is suggested that the whole efferent system (from cerebral cortex to olivocochlear bundle) would be of great importance for cochlear function.

[A study on the contralateral suppressive effects of distortion product otoacoustic emissions]

To investigate the physiological properties of contralateral suppressive effects of otoacoustic emissions, the effects of contralateral norrow band noise (NBN) on distortion product otoacoustic emissions (DPOAE) in 23 young subjects (46 ears) with normal hearing were studied using ILO92 otodynamic system. The results showed: 1. The amplitude of DPOAE (2f1-f2) was significantly reduced as the intensity of contralateral NBN increased. They were in significant minus correlation (F2 from 1 to 6 kHz, coefficients were -0.49(-)-0.24, all P < 0.05, the slope 0.26-0.08 dB/10 dB); 2. The suppressive effect was the biggest when the primary F2 was 1 kHz or 2 kHz and between 45 dB SPL and 65 dB SPL of intensity level, and damped as primary frequency increased. The most significant reduction of DPOAE amplitude was 3.85 dB SPL; 3. When contralateral NBN was below 50 dB HL, the suppression was frequency-selective; and the most suppressive effect happened when NBN intensities were between 20 dB HL and 50 dB HL. 4. The noise floor in ipsilateral car canal has not been altered by contralateral noise (20-50 dB HL). The underlying mechanism was discussed in this study. It appears that contralateral suppressive effects of DPOAE can be used as a tool in exploring the function of medial olivocochlear system.

[Extraction, purification and ascertainment of anti-hepatoma active principles for targeted preparation of radix Aconiti Kusnezoffii]

The extraction, purification, pharmacological experiments and chemical analysis of anti-hepatoma active principles of Radix Aconiti Kusnezoffii have been studied. The results show that the medicinal material Radix Aconiti Kusnezoffii is efficacious in inhibiting hepatoma, and the active principles are mainly made up of poisonous ester alkaloids. The liver targeting delivery system will be the first choice for its anti-hepatoma preparation, and the effective component AY3a is fit for the preparation of targeted microspheres.

[The effect of GM-CSF on endothelin-1 and endothelin converting enzyme gene expression in human airway smooth muscle cells with or without theophylline incubation]

OBJECTIVE

To explore the role of airway smooth muscle cells (ASMC) stimulated by inflammatory factors in the development of asthma and bronchial hyperresponsiveness (BHR) and the possible mechanism of low dose theophylline in the treatment of airway inflammation, the effects of GM-CSF on endothelin-1 and endothelin converting enzyme (ECE) gene expression in human ASMC and theophylline on their expressions were investigated.

METHOD

The cultured human ASMCs were treated with GM-CSF (1,000 micrograms/ml), GM-CSF plus theophylline (125 ng/ml) respectively for 8 hours. Endothelin-1 and ECE gene expresion were measured by RT-PCR.

RESULT

There was no ET-1 gene expression in control group, but strong expression in GM-CSF treated group; theophylline entirely inhibited GM-CSF induced ET-1 gene expression in the ASMC; no significant difference of ECE gene expression was found in three groups.

CONCLUSION

GM-CSF causes a strong ET-1 gene expression but not ECE gene expression in cultured human airway smooth muscle cells; theophyllin inhibites this abnormal expression which may be one of the anti-inflammatory mechanisms of low dose theophylline in the management of chronic airway inflammation.

[Chronic airway inflammation and atopic features in cough variant asthma]

OBJECTIVE

To elucidate the chronic airway inflammation and atopic features in 17 patients with cough variant asthma (CVA).

METHODS

(1) Allergen skin prick test, and the atopy index (AI) calculation. (2) Fiberoptic bronchoscopy, inflammatory score of airway membrane under bronchoscopy. (3) Biopsy of the airway membrane and calculation of the eosinophil infiltration. (4) Bronchoalveolar lavage, classification of various cells in the BALF. (5) House dust mite and rabbit antihuman IgE induced histamine release from mast cell. The results were compared with those in 9 patients with typical asthma (Group 8) and 7 normal subjects (Group C).

RESULTS

The number of EOS and mast cells in BALF and the AI of CVA group were found higher than in control group.

CONCLUSION

(1) Similar to typical asthma, IgE dependent type I allergic reaction plays an important role in the pathogenesis of CVA. (2) Chronic inflammation including eosinophil infiltration was shown in airway membrane in CVA. (3) Bronchial hyperresponsiveness and chronic inflammation of the airway membrane in CVA are less severe than those in typical asthma. (4) In patients who are in difficulty of making a diagnose of CVA clinically. BAL and biopsy of the bronchial membrane will help to make a definite diagnosis.

[Study of optimal parameters and normal values for auditory P300]

Study of optimum seeking method with orthogonal test for auditory P300 measuring was carried out in healthy adolescents. The result showed that the optimal conbination of parameters was as follows: stimulus sound was Logon, recording electrode site Cz, analysis time 750 ms, average 100, stimulus rate 1 c/s, target stimulus (TS) probability 10%, bandpass filter 1-50 Hz, non-target stimulus (NTS) freqency 1 kHz, target stimulus (TS) frequency 2 kHz, stimuli intensities 110 dB peSPL. The normal values of auditory P300, obtained from 30 healthy adolescents, including latencies and amplitudes, were measured under optimal parameters. P300 latency was about 310 ms, RT about 258 ms, these two values present a significant linear correlation.

[Audiologic measure in Ménière's disease]

To determine some audiologic phenomena of Ménière's disease before and after ingestion of dehydration agent and evaluate its diagnostic value, 48 ears of Ménière's disease, 40 ears of other vertigo disease and 40 normal ears were investigated. The measures were undertaken before and after glycerol or urea ingestion, which included threshold of pure tone audiometry, peak static acoustic admittance (Ya) and conductance(Ga) at probetone signal of 678 Hz, peak compensate static admittance(delta Y) and conductance(delta G) at resonance frequency, -SP/AP, and width of SP-N1 in ECochG. Results showed that abnormal rates of glycerol group and urea group were similar, and there was no significant statistical difference. So these two groups were combined together as one in statistics. The rate of totally abnormal ears were 17/32 in seven measures. Abnormal rates of dehydration test were: pure audiometry 66.67%, Ga 62.50%, -SP/AP 52.08%, width of SP-AP N1 66.67%. chi 2 test showed no significance statistical difference among these results. It indicated that these measures had same diagnostic value for the Ménière's disease. The shift value of G a and delta G of dehydration test might be as the objective diagnostic methods of Ménière's disease.

[Effects of chronic hypoxia on the expression of oncogene jun fos and myb mRNA in rat lung]

This paper is to investigate the expression of oncogene jun fos and myb mRNA in the lung of rats exposed to chronic hypoxia. 15 SD rats were put in low oxygen chamber (FiO2 = 0.1), 8 hrs daily for 1, 2 and 3 weeks. Five rats breathing room air served as control. Oncogene expression in lung tissue assessed by the use of in situ hybridization. The results showed that (1) there was a slight expression of jun mRNA but not fos and myb mRNA in the control normoxic rats' lung; (2) it was found that a less expression of jun mRNA in lung after 1 week hypoxia, but after 2 week hypoxia jun mRNA elevated again and significantly increased after 3 week hypoxia as compared with that in normoxia; (3) the oncogene myb mRNA expression showed significant increase in 1 and 2 week hypoxia and returned to normal status in 3 week hypoxia; (4) after 1 to 3 week hypoxia, a significant increased expression of fos mRNA was found as compared with that in normoxia. It is suggested hypoxia may induce increased expression of proto-oncogene jun myb and fos, which may be related to proliferation of pulmonary arterial smooth muscle cells and fibroblasts.

Expression studies of CLN3 protein

Expression of the gene for Batten disease (CLN3) was studied in Escherichia coli and in a cell-free rabbit reticulocyte expression systems. A full-length recombinant fusion CLN3 protein was not produced in the bacterial systems used. However, both N-terminal fragment encompassing 246 amino acids and short C-terminal fragment containing 428-438 amino acids of the CLN3 protein were successfully overexpressed in bacteria. Further studies showed that the C-terminal sequence of the CLN3 protein corresponding to the 356-438 amino acid residues was responsible for inhibition of protein synthesis in bacteria. The full-length CLN3 gene product was readily synthesized in vitro in the cell-free rabbit reticulocyte expression system. The product obtained, corresponding to core CLN3 protein, showed an approximate molecular weight of 43 kDa. Immunoprecipitation of this product with pAb to 4-19 amino acids of the CLN3 protein allows us to suggest that CLN3 protein translation starts at Met-1.

Atypical late infantile and juvenile forms of neuronal ceroid lipofuscinosis and their diagnostic difficulties

We have collected 122 late-infantile neuronal ceroid lipofuscinosis (LINCL, CLN2) and 191 juvenile NCL (JNCL, CLN3) cases, diagnosed on the basis of age-at-onset, clinical symptomatology, and pathological findings and representing the most common forms of NCL in the United States, and Europe. However, careful analysis of available data revealed that about 80% of cases show typical and 20% show atypical clinical course and/or pathological findings and thus, may represent variants of LINCL and JNCL, respectively. Recent progress in the biochemistry and molecular genetics of NCL inclined us to reevaluate these atypical NCL cases. The gene responsible for LINCL has not yet been identified, except for the Finnish variant. Accumulation of subunit c of mitochondrial ATP synthase, to curvilinear profiles, is found in LINCL cases. A novel variant of LINCL, with predominantly granular profiles in the lysosomal storage, as well as normal excretion of subunit c in urine samples, was found in five cases. When the palmitoyle-protein thioesterase (PPT) was studied in these five cases, it was found that the level was deficient, suggesting that they are not LINCL, but the infantile form of neuronal ceroid lipofuscinosis (INCL). Using molecular genetic techniques in the typical JNCL cases, common 1.02 kb deletion to CLN3 was found in 23/27 (homozygotes) and in one allele 4/27 (heterozygotes) in affected pedigrees. In atypical JNCL pedigrees, it was found in 5/16 heterozygotes, while in 1/5 pedigrees, a novel mutation of one atypical JNCL where a single amino acid substitution at 295 E-->K was found in one allele. None of the atypical JNCL cases was homozygote. In atypical JNCL cases where mutation in CLN3 has not been identified (11/16 probands), several possibilities may exist. The phenotype may be caused by a yet undefined mutation in CLN3 or may be due to phenotypically overlapping with other forms of NCL. Pheno/genotypic correlation and the diagnostic difficulties are discussed.

Tissue differences in fragile X mosaics: mosaicism in blood cells may differ greatly from skin

The fragile X mutation is diagnosed from the structure of the FMR1 gene in blood cell DNA. An estimated 12 to 41% of affected males are mosaics who carry both a "full mutation" allele from which there is no gene expression and a "premutation" allele which has normal gene expression. We compared the DNA in blood cells and skin fibroblasts from four mosaic fragile X males to see if there was a difference in the relative amounts of premutation and full mutation alleles within the tissues of these individuals. Two of these males showed striking differences in the ratio of premutation to full mutation in different tissues while the other two showed only slight differences. These observations conform with the widely accepted hypothesis that the fragile X CGG repeat is unstable in somatic tissue during early embryogenesis. Accordingly, the mosaicism in brain and skin, which are both ectodermal in origin, may be similar to each other but different from blood which is not ectodermal in origin. Thus, the ratio of full mutation to premutation allele in skin fibroblasts might be a better indicator of psychological impairment than the ratio in blood cells.

Tissue differences in fragile X mosaics: mosaicism in blood cells may differ greatly from skin

The fragile X mutation is diagnosed from the structure of the FMR1 gene in blood cell DNA. An estimated 12 to 41% of affected males are mosaics who carry both a "full mutation" allele from which there is no gene expression and a "premutation" allele which has normal gene expression. We compared the DNA in blood cells and skin fibroblasts from four mosaic fragile X males to see if there was a difference in the relative amounts of premutation and full mutation alleles within the tissues of these individuals. Two of these males showed striking differences in the ratio of premutation to full mutation in different tissues while the other two showed only slight differences. These observations conform with the widely accepted hypothesis that the fragile X CGG repeat is unstable in somatic tissue during early embryogenesis. Accordingly, the mosaicism in brain and skin, which are both ectodermal in origin, may be similar to each other but different from blood which is not ectodermal in origin. Thus, the ratio of full mutation to premutation allele in skin fibroblasts might be a better indicator of psychological impairment than the ratio in blood cells.

Familial transmission of the FMR1 CGG repeat

To better define the nature of FMR1 CGG-repeat expansions, changes in allele sizes for 191 families with fragile X and for 33 families with gray-zone repeats (40-60) were analyzed. Expansion of the fragile X chromosome to the full mutation was seen in 13.4% of offspring from premutation mothers with 56-59 repeats, 20.6% of those with 60-69 repeats, 57.8% of those with 70-79 repeats, 72.9% of those with 80-89 repeats, and 97.3% of those with 90-199 repeats. For premutation fathers, the majority (62%) of their daughters had a larger repeat number, while a few had either a smaller (22%) or the same (16%) repeat number, compared with their fathers' sizes. However, daughters with a smaller repeat number were observed only if their fathers had > or = 80 repeats. Fifteen (39.5%) of 38 such daughters carried a smaller repeat than did their fathers. We observed that a similar repeat number was inherited more often than expected by chance, among the members of a sibship segregating fragile X. This familial clustering, observed in the offspring of both males and females with a premutation, implies there may be an additional factor, independent of parental repeat size, that influences CGG-repeat instability. Instability in gray-zone allele transmissions was observed in 25% of alleles with 50-60 CGGs but in <8% of those with 40-49 CGGs. Examination of gray-zone allele organization revealed that long tracts of pure CGGs (>34) are not always unstably transmitted. These results raise new questions regarding the familial factors that may determine transmission expansions.

[Prediction of the level of continuous positive airway pressure in the management of obstructive sleep apnea syndrome via nasal mask]

OBJECTIVE

To predict and optimal level of continuous positive airway pressure (CPAP) in the menagement of obstructive sleep apnea syndrome (OSAS) by relating certain parameters of respiratory disturbance and sleep hypoxemia.

METHODS

18 patients with OSAS (all male, aged 48 +/- 11 yrs) were enrolled in the study. Their actual levels of CPAP (Pm) were determined by a RHK-5500 mode polysomnographic system plus BiPAP (ST/D) system. The actuual Pm was related to the respiratory disturbance index (RDI) or total time of SaO2 < or = 90% (T S90). The correlation regression equations were calculated. 6 patients with OSAS (Group A) were treated with the predicted nasal CPAP (predicted Pm) which was derived from the regression equation, 8-10 hours per night, for 5-7 nights. 13 patients (Group B) receiving nasal CPAP treatment using the actually measured Pm served as control.

RESULTS

There was a close positive linear correlation between RDI or T S90 and actual Pm. Symptoms and polysomnographic parameters improved significantly after one course of CPAP treatment in Group A. The efficacy showed no signifcant different as compared with that in Group B.

CONCLUSIONS

It was suggested that RDI or T S90 are of value and simple in predicting the pressuure level of CPAP in the management of OSAS with nasal CPAP.

Fragile X "gray zone" alleles: AGG patterns, expansion risks, and associated haplotypes

The risk for fragile X "gray-zone" alleles to expand appears to depend on the absence of stabilizing AGGs, which interrupt the CGG repeat region. To characterize such alleles better, we analyzed a series of 101 chromosomes with triplet repeat lengths ranging from 35 to 59 for variations in their AGG interspersion patterns. Among these, 11.9% had 3 AGGs, 59.3% had 2, 24.8% had 1, and 4.0% had 0. An inverse relationship between FMR1 repeat length and the number of interrupting AGGs was observed. Within the range of 35-44 repeats, 98.7% of alleles were found to have a pure CGG repeat length (PCGG) of less than 33. However, among alleles with 45-59 repeats, 50% were found to have 0 or 1 AGG and a PCGG of more than 33. Thus, gray-zone alleles with 45-59 repeats frequently have a long stretch of pure CGGs and thus are more likely to be unstably inherited than alleles with 35-44 repeats. We found length associations of PCGG with 2 flanking microsatellites, DXS548 and FRAXAC1: a PCGG < or = 20 was strongly associated with haplotype 20-19, whereas a PCGG > 20 was more strongly associated with the haplotype 25-21. This result could reflect a founder effect or a generalized instability of CGGs and microsatellites.

Reverse mutations in the fragile X syndrome

Three females were identified who have apparent reversal of fragile X premutations. Based on haplotype analysis of nearby markers, they were found to have inherited a fragile X chromosome from their premutation carrier mothers, and yet had normal size FMR1 repeat alleles. The changes in repeat sizes from mother to daughter was 95 to 35 in the first, 145 to 43 in the second, and 82 to 33 in the third. In the first family, mutations of the nearby microsatellites FRAXAC2 and DXS548 were also observed. In the other two, only mutations involving the FMR1 repeats were found. We suggest differing mutational mechanisms such as gene conversion versus DNA replication slippage may underlie such reversions. We estimate that such revertants may occur among 1% or less of premutation carrier offspring. Our results indicate that women identified to be carriers by linkage should be retested by direct DNA analysis.

Tissue differences in fragile X mosaics: mosaicism in blood cells may differ greatly from skin

The fragile X mutation is diagnosed from the structure of the FMR1 gene in blood cell DNA. An estimated 12 to 41% of affected males are mosaics who carry both a "full mutation" allele from which there is no gene expression and a "premutation" allele which has normal gene expression. We compared the DNA in blood cells and skin fibroblasts from four mosaic fragile X males to see if there was a difference in the relative amounts of premutation and full mutation alleles within the tissues of these individuals. Two of these males showed striking differences in the ratio of premutation to full mutation in different tissues while the other two showed only slight differences. These observations conform with the widely accepted hypothesis that the fragile X CGG repeat is unstable in somatic tissue during early embryogenesis. Accordingly, the mosaicism in brain and skin, which are both ectodermal in origin, may be similar to each other but different from blood which is not ectodermal in origin. Thus, the ratio of full mutation to premutation allele in skin fibroblasts might be a better indicator of psychological impairment than the ratio in blood cells.

A survey of FRAXE allele sizes in three populations

FRAXE is a fragile site located at Xq27-8, which contains polymorphic triplet GCC repeats associated with a CpG island. Similar to FRAXA, expansion of the GCC repeats results in an abnormal methylation of the CpG island and is associated with a mild mental retardation syndrome (FRAXE-MR). We surveyed the GCC repeat alleles of FRAXE from 3 populations. A total of 665 X chromosomes including 416 from a New York Euro-American sample (259 normal and 157 with FRAXA mutations), 157 from a Chinese sample (144 normal and 13 FRAXA), and 92 from a Finnish sample (56 normal and 36 FRAXA) were analyzed by polymerase chain reaction. Twenty-seven alleles, ranging from 4 to 39 GCC repeats, were observed. The modal repeat number was 16 in the New York and Finnish samples and accounted for 24% of all the chromosomes tested (162/665). The modal repeat number in the Chinese sample was 18. A founder effect for FRAXA was suggested among the Finnish FRAXA samples in that 75% had the FRAXE 16 repeat allele versus only 30% of controls. Sequencing of the FRAXE region showed no imperfections within the GCC repeat region, such as those commonly seen in FRAXA. The smaller size and limited range of repeats and the lack of imperfections suggests the molecular mechanisms underlying FRAXE triplet mutations may be different from those underlying FRAXA.

Fragile X founder effects and new mutations in Finland

The apparent associations between fragile X mutations and nearby microsatellites may reflect both founder effects and microsatellite instability. To gain further insight into their relative contributions, we typed a sample of 56 unrelated control and 37 fragile X chromosomes from an eastern Finnish population for FMR1 CGG repeat lengths, AGG interspersion patterns, DXS548, FRAXAC1, FRAXE and a new polymorphic locus, Alu-L. In the controls, the most common FMR1 allele was 30 repeats with a range of 20 to 47 and a calculated heterozygosity of 88%. A strong founder effect was observed for locus DXS548 with 95% of fragile X chromosomes having the 21 CA repeat (196 bp) allele compared to 17% of controls, while none of the fragile X but 69% of controls had the 20 repeat allele. Although the FRAXAC1 locus is much closer than DXS548 to FMR1 (7 kb vs. 150 kb), there was no significant difference between fragile X and control FRAXAC1 allele distributions. The FRAXE repeat, located 600 kb distal to FMR1, was found to show strong linkage disequilibrium as well. A newly defined polymorphism, Alu-L, located at approximately 40 kb distal to the FMR1 repeat, showed very low polymorphism in the Finnish samples. Analysis of the combined loci DXS548-FRAXAC1-FRAXE showed three founder haplotypes. Haplotype 21-19-16 was found on 27 (75%) of fragile X chromosomes but on none of controls. Three (8.4%) fragile X chromosomes had haplotypes 21-19-15, 21-19-20, and 21-19-25 differing from the common fragile X haplotype only in FRAXE. These could have arisen by recombination or from mutations of FRAXE. A second haplotype 21-18-17 was found in four (11.1%) fragile X chromosomes but only one (1.9%) control. This may represent a more recent founder mutation. A third haplotype 25-21-15, seen in two fragile X chromosomes (5.6%) and one (1.9%) control, was even less common and thus may represent an even more recent mutation or admixture of immigrant types. Analysis of the AGG interspersions within the FMR1 CGG repeat showed that 7/8 premutation chromosomes lacked an AGG whereas all controls had at least one AGG. This supports the hypothesis that the mutation of AGG to CGG leads to repeat instability and mutational expansion.

[The correlation of auditory brainstem response and transcranial Doppler on the vertebrobasilar transient ischemic vertigo]

To investigate the correlation of brainstem response (ABR) and transcranial doppler examination (TCD) on the vertebrobasilar transient ischemic vertigo (VBTIV), 24 patients (48 ears) with VBTIV and 12 patients (24 ears) with non-VBTIV were studied. The results showed that the incidence of abnormality of ABR in VBTIV group was 58.3%, TCD 54.2%, there being no significant difference by Chi-square test; while in non-VBTIV group ABR 8.3%, TCD 45.8%. Both ABR and TCD were abnormal in VBTIV 19/48, non-VBTIV 0/24 and normal VBTIV 13/48, non-VBTIV 11/24. The ratio of there cases (normal and abnormal) as a whole was VBTIV 66.7%, non-VBTIV 45.8%. It indicates that ABR with high stimulus rates combined with TCD and clinical signs can make the diagnosis of VBTIV. The results of TCD alone can't be a considerable diagnostic basis for VBTIV.