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Biomedical subjects

D Ni

Publications and source records attributed to D Ni.

At least 19 recordsLinked to original sources
PubMed2001

[Neurological manifestations of isolated sphenoiditis].

OBJECTIVE: To review the neurological manifestations of isolated sphenoiditis. METHODS: The symptoms, signs, imaging data, diagnoses and outcomes of 14 cases with sphenoiditis hospitalized in Peking Union Hospital June 1995-January 2001 were analyzed retrospectively. RESULTS: The chief complaints of this group included headache (12 cases), visual loss and/or diplopia (7 cases), blood in nasal discharge (3 cases), purulent nasal discharge (2 cases), exophthalmoptosis (1 case), fixation of eyeball (1 case), and pharyngodynia (1 case). Six patients presented deficits of the second and/or third, fourth, and sixth cranial nerves; one patient had hemiplegia and aphasia; no more presentation of nervous system was found in all patients. Only five patients showed signs of posterior sinusitis in rhinologic examination. CT and/or MRI revealed isolated sphenoiditis (11 cases) and sphenoiditis with posterior ethmoiditis (3 cases). The complications of this group were intracranial infection involving frontal, temporal, and parietal lobes and brainstem (1 case), aneurysm of cavernous carotid artery (1 case), nasal cerebrospinal fluid leakage (1 case), optic neuritis (5 eyes), abducent paralysis (2 cases), orbital cellulitis (1 case) and orbital apex syndrome (1 case). All of the patients underwent endoscopic sphenoid surgery. 13 patients were free of headache after surgery. One patient died because of hernia of brain. CONCLUSION: Headache can be the first or unique symptom of isolated sphenoiditis. Isolated sphenoiditis should be considered in diagnosis and differential diagnosis of headache. CT and MRI are the best tools in diagnosis of isolated sphenoiditis.

Adolescent↗
PubMed2001

[Study of pharyngo-cutaneous fistula after total laryngectomy].

OBJECTIVE: To explore the factors which lead to pharyngo-cutaneous fistula after total laryngectomy. METHOD: A retrospective study of 125 patients who underwent total laryngectomy during a 16-year period was carried out. RESULT: The rate of post-laryngectomy pharyngo-cutaneous fistula is 16.0% (20/125), it appears reduced tendency. With single-factor analysis, the factors effect on the rate of post-laryngectomy pharyngo-cutaneous fistula include clinical tumor stage, tumor types, pre-operative radiotherapy dose, intraoperative blood transfusion, operative duration. With all variable logistic model analysis, the factors effect on the rate of pharyngo-cutaneous fistula are clinical tumor stage and pre-operative radiotherapy dose, but pre-operative radiotherapy is very possible to be a risk factor (P = 0.0566). With logistic model stepwise regression analysis, the factors effect on the rate of pharyngo-cutaneous fistula are clinical tumor stage and operative duration. CONCLUSION: Pharyngo-cutaneous fistula appears easily in patients with T3, T4 tumor, and have pre-operative radiotherapy, especially have large dose preradiotherapy. For these high risk patients, the duration of operation should be as short as possible to reduce the rate of post-laryngectomy pharyngo-cutaneous fistula.

Adult↗
PubMed2000

IFN-alpha1a gene is the major variant in the North American population.

Thirteen interferon (IFN)-alpha functional genes have been reported. A number of these genes have allelic members (variants). In the case of IFN-alpha1, two variants, IFN-alpha1a and IFN-alpha1b, are known. The variants differ from each other by one base change in the coding region, leading to a single change in amino acid sequence and the presence of a restriction site. We have developed oligonucleotide primers for amplification of IFN-alpha1 gene(s) using polymerase chain reaction (PCR). Genomic DNA, obtained from over 23,000 normal healthy individuals and from four human cell lines, were used as templates in PCR to amplify the IFN-alpha1 gene sequences. The resulting PCR products were analyzed by restriction endonuclease digestion and DNA sequencing to identify the presence of variant sequences. The results show that IFN-alpha1a is predominant in the genomic DNA of the population examined. Among the cell lines studied, IFN-alpha1a is the only variant found in U-937 and Namalwa cells, whereas KG-1 cells have only IFN-alpha1b, and EB-3 cells have both IFN-alpha1a and IFN-alpha1b in the genome.

Alleles↗
PubMed2000

[Alteration of free radical generation in pulmonary tissue after quick decompression].

The purpose of this experiment was to evaluate decompression-induced pulmonary injury by means of measurement of ascorbate free radical (Vc-.) alteration in pulmonary tissue of the rats which experienced rapid decompression. 29 male S-D rats were divided into 4 groups: A was executed at 45 min post-decompression; B was control for A; C was executed at 90 min; D was ontrol for C. Group A and group C were to compress up to 0.5 MPa(air) and stay for 60 min, then were decompressed smoothly to normbaric in 1 min. The 0.05 M N-tert-butyl-alpha-phenylnitrone (PBN) was given at 20 min after completion of decompression (groups A and B) or at 65 min (groups C and D). At 25 min after PBN injection the animals were killed by cutting arteria coeliaca, and 0.75 g pulmonary tissues were taken. These tissues were homogenized for electron paramagnetic resonance (EPR) assay. The results demonstrated that the ascorbate free radical (Vc-.) signals were obtained at all samples. The intensity of signals measured in group C rose markedly (P < 0.05) and that in group A was close to control's. So it can be concluded that rapid decompression would increase the generation of free radical in lung.

Animals↗
PubMed1999

Suppressing effect of substance P receptor antagonist on sound evoked potentials recorded from the guinea pig cochlea.

OBJECTIVE: To investigate the regulation of SP in the cochlea function. METHODS: Ten adult guinea pigs were used as experimental animals. The perilymph space of the guinea pigs cochlea was perfused with artificial perilymph solution containing 1 microgram/microliter SP receptor antagonist (D-Arg1, D-Pro2, D-Trp7,9, Leu11)-SP (1-11) at a rate of 2.5 microliters/min for 10 min while monitoring cochlear potentials evoked by 4 kHz tone burst. RESULTS: The perfusion of SP antagonist resulted in a suppression of the compound action potential of the auditory nerve (CAP, N1-P1), a prolongation of the N1 latency at threshold and suprathreshold levels, an elevation of the CAP threshold. CONCLUSIONS: These results suggest that SP might play a role as a transmitter or modulator in the cochlear function.

Action Potentials↗
PubMed1999

[Vestibular potentials evoked by electrical stimulation].

OBJECTIVE: To identify the evoked potentials (VsEPs) by electrical stimulation were from vestibule. METHODS: The stimulating electrode was set on the round window of guinea pig. Constant current shocks of 0.05 ms (0.25-1.2 mA) were used to evoke VsEPs by means of vertex-pinna skin electrodes. RESULTS: These potentials were short latencies of (0.973 +/- 0.086) ms, (1.618 +/- 0.176) ms and (2.416 +/- 0.274) ms respectively, which reflected true potentials and were not from electrical stimulus artefacts. It was pure vestibular origin. As being masked with a continuous white noise (120 dB SPL) or removed ipsilateral auditory nerve, and even after facial neurectomy, waves were still existing, but disapeared after selective vestibular neurectomy. The twitching responses in the facial region had never been detected during the whole test. These potentials were bioelectric responses in the vestibular sensory pathway, characterized by threshold saturation, adaptability of excitation, dependent on intact vestibular nerve. CONCLUSIONS: We have set up animal model of recording VsEPs evoked by electrical stimulation on the round window of guinea pigs.

Animals↗
PubMed1999

[Olfactory evoked potentials produced by electrical stimulation of the olfactory mucosa].

OBJECTIVE: To develop an objective olfactometric method. METHODS: Electrically evoked olfactory potentials were recorded in 20 rabbits with 0.2-4.0 mA electrical stimulations. The stimulating electrodes were placed on the olfactory and respiratory regions of the nasal mucosa. Recording electrode was placed on the scalp near the olfactory bulb. RESULTS: Electrically evoked olfactory potentials composed of triphasic negative-positive-negative peaks, named N1, P1, N2 respectively, were detected on the olfactory region. The latencies of N1, P1, N2 were 16.27 ms, 25.36 ms, 49.75 ms respectively in cribriform plate. No electrically evoked potentials were detected on the respiratory mucosa, nor did on the olfactory mucosa after olfactory neurectomy. CONCLUSION: Steady and clear electrically evoked olfactory potentials which originated from olfactory neurosystem were detected on olfactory mucosa in rabbits.

Animals↗
PubMed1999

[Pharyngoscopic observation during sleep in patients with obstructive sleep apnea syndrome].

OBJECTIVE: To analyse collapse sites of pharynx and their anatomical causes during sleep in patients with obstructive sleep apnea syndrome(OSAS), and compared with the results of Muller's maneuver. METHODS: The pharynges in 43 sleeping patients with OSAS were examined endoscopically. The area changes at each segment(velo-, oro- and hypopharynges) were calculated during the episodes of apnea. A site having greater than 75% narrowing of airway lumen was defined as a narrowing or obstructive site. RESULTS: 1. All patients had obstruction at velopharynx during asleep. Airway collapses at multiple sites in 79% of cases(28% at velo- and oropharynx; 21% at velo- and hypopharynges; and 30% at velo-, oro- and hypopharynges). 2. At each segment the anatomical factors causing obstruction were variable among patients. The common abnormalities were posterior displacement of soft palate or uvula, enlarged tonsil, thicken or posterior displacement of tongue base, collapse of pharyngeal wall, redundant mucosa or lateral bands of pharynx etc. 3. The positivity of pharyngeal obstruction was higher in this study as compared with of Muller's maneuver the latter was taken place while the patient was awaken. Comparison of the positive rate of the narrowing sites determined between sleep observation and Muller's maneuver in same patients: at velopharynx(100% vs 91%), at oropharynx (58% vs 42%) and at hyperpharynx (51% vs 28%). CONCLUSION: Multiple obstructions in the pharynx are common. Examination of the pharynx during asleep may be more accurate then while the patient was awaken.

Female↗
PubMed1999

[Audiologic analysis of a family with nonsyndromic genetic progressive sensorineural hearing loss].

OBJECTIVE: To analyze the audiological data collected from a large six-generation family with nonsyndromic genetic progressive sensorineural hearing loss. METHODS: There were 104 members in the family who could provide the hearing data, in which 46 individuals had hearing impairment. The pure tone threshold in 56 individuals and ABR in 49 individuals were analyzed. The pedigree of 104 family members with 6 branches was made. RESULTS: Hearing impairment was found in the second decade. The hearing thresholds of high and mid frequencies were deteriorated up to 110 dB HL in the fourth decade. The hearing loss started from high frequencies and quickly expended to mid and low frequencies. The regression analysis of pure tone thresholds of 4 kHz and 8 kHz in 6 cases with ages from 10 to 20 years were carried out. The regression coefficients, or the annual threshold increases were 15.96 dB and 15.34 dB per year, respectively. ABR results showed that the hearing loss was caused by cochlear impairment. The pedigree of family indicated high or complete penetrance. CONCLUSION: The medical history and audiological analysis of the family members showed that this hearing impairment was nonsyndromic autosomal dominant progressive sensorineural hearing loss. The hearing impairment and onset age in this family were different from those families with 13 loci related autosomal dominant nonsyndromic sensorineural hearing loss reported previously. The genetic linkage study showed that it could not link to these regions and other two regions reported recently in Internet.

Adolescent↗
PubMed1998

Action of antitumoral platinum complexes on in vitro platelet functions.

This report presents a comparison of the effects of cis- and trans-diamminedichloroplatinum complexes on in vitro platelet functions. Pretreatment of platelets with cis-platinum (cisplatin) induced a slow, dose-dependent (0.1-0.45 mM), increase in the cytosolic Ca2+ concentration, pleckstrin (47 kDa) phosphorylation and serotonin secretion, as well as a slight shape modification with emission of a few pseudopodia. All these effects were remarkably increased in platelets exposed to trans-platinum (transplatin). The rise in cytosolic Ca2+ concentration and serotonin secretion evoked by stimulation of platelets with thrombin were not significantly influenced by cellular exposure to cis-platinum, whereas they were enhanced and inhibited, respectively, by exposure to trans-platinum. Trans-platinum also inhibited thrombin-promoted platelet aggregation to a greater extent than the cis-isomer. While the viscosity of platelet rich-plasma tended to decrease in the presence of cis-platinum, it tended to increase in the presence of trans-platinum. Taken together, these results indicate that the effects on platelet functions of the efficacious antitumor complex cis-platinum is rather different from that of the inactive complex trans-platinum. Therefore, the in vitro tests of platelet functions employed in this study might provide an index of antitumor drug toxicity and serve as a preliminary indicator of therapeutic efficacy.

Antineoplastic Agents↗
PubMed1998

A new allele of interferon-alpha17 gene encoding IFN-alpha17b is the major variant in human population.

Thirteen interferon (IFN)-alpha functional genes have been reported. Among these, a number of genes have allelic members (variants). In the case of IFN-alpha17, five variants, IFN-alpha17a, IFN-alpha17b, IFN-alpha17c, IFN-alpha17d, and IFN-alphaT, are known. The variants differ from each other by base changes in the coding region, leading to differences in amino acid sequences. We have developed oligonucleotide primers for amplification of IFN-alpha17 gene(s) using polymerase chain reaction (PCR). Genomic DNA, obtained from over 28,000 normal healthy individuals and from four cell lines, were used as templates in PCR to amplify the IFN-alpha17 gene sequences. The resulting PCR products were analyzed by restriction endonuclease digestion and DNA sequencing to identify the presence of variant sequences. The results show that a new variant of IFN-alpha17 is abundantly present (approximately 70%) along with another variant, possibly IFN-alpha17c (approximately 30%), in the genomic DNA of the population examined. This new variant, the protein product of which is identical to IFN-alpha17b, differs from the gene for IFN-alpha17b by a point mutation. We have named it IFN-alpha17b', which is the only variant found in U-937, KG-1, and EB-3 cell lines. Namalwa cells have IFN-alpha17b' and, possibly, IFN-alpha17c in equal proportions.

Alleles↗
PubMed1998

[The effection of obstructing OCB with strychnine on the guinea pig's DPOAE].

The strychnine was used to obstruct the oliver cochlear bundle (OCB) in order to explore the effect of the efferent system on distortion product otoacoustic emission (DPOAE) of guinea pig. The result showed that the DPOAE were not changed after strychnine were administrated. It is concluded that the efferent pulses of the CNS does not affect on DPOAE in silent circumstance.

Animals↗
PubMed1998

[Distortion product otoacoustic emissions in normally hearing young humans].

OBJECTIVE: To investigate the basic properties of distortion product otoacoustic emissions (DPOAE) in normally hearing subjects of China. METHODS: DPOAE "audiogram" (DP-gram) and input/output functions (I/O functions) were recorded from 24 normally hearing young humans with Celesta-503 cochlear emissions analyzer. RESULTS: The prevalence of DPOAE was 100% ranging in frequency from 500 to 8,000 Hz, with respect to the geometric means of f1 and f2 stimuli. The mean DP-gram had two peaks at about 1,000 Hz and 6,000 Hz and a dip at about 3,000 Hz. The higher amplitude of DPOAE was recorded at about 3,000 Hz when using unequal primary-tone levels (L1 > L2). The mean thresholds of DPOAE were between 25 and 40 dB SPL. The thresholds of DPOAE decreased with increasing primary-tone frequencies. The I/O slopes were higher at about peak freqencies than at other frequencies. For all the results of DPOAE in left and right ears, there were no apparent differences by statistics. CONCLUSIONS: By systematical studies of the properties of DPOAE in normally hearing ears of Chinese subjects, this paper provides basic reference data for clinical application of DPOAE.

Adolescent↗
PubMed1998

[Preoperative nasal continuous positive airway pressure treatment as substitute for protective tracheostomy in severe obstructive sleep apnea syndrome].

OBJECTIVE: Preoperative nasal continuous positive airway pressure(NCPAP) treatment was used as a substitute for protective tracheostomy before UPPP surgery in 42 patients with severe obstructive sleep apnea syndrome(OSAS) from 1994 to 1996. METHODS: Fifty-two patients operated on three years before this period served as control group. All cases were diagnosed as severe OSAS by polysomnography (PSC). RESULTS: There were no statistical difference in main parameters between two groups. Seven cases in the control group underwent protective tracheostomy whose apnea and hypopnea index(AHI) was 28.4-83.5 and lowest saturation oxygen (SaO2) were 7%-32%. One patient underwent emergency tracheostomy due to life-threatening situation during uvulopalatopharyngoplasty (UPPP). There were 9 similarly severe cases who did not undergo protective tracheostomy in NCPAP treatment group. All patients underwent preoperative 5-20 day NCPAP treatment in treatment group. The average positive pressure was 1.16 kPa(11.85 cmH2O). There were significant difference in main parameters between the two groups. The AHI, SaO2 and sleep structure were evidently improved. UPPP was safely performed without protective tracheostomy and any complications in all patients with NCPAP treatment. CONCLUSION: This result implys that NCPAP treatment could be used as a substitute for protective tracheostomy before UPPP in severe OSAS.

Adolescent↗
PubMed1998

[The diagnosis of non-pituitary space-occupied lesions in sphenoidal sinus and sellar area].

OBJECTIVE: To improve the diagnostic accuracy of non-pituitary lesions in sphenoidal sinus and sellar area. METHODS: Twenty-four cases with non-pituitary lesions in sphenoidal sinus and sellar area were analyzed. Eighteen cases were benign, including 7 sphenoidal sinus cyst, 6 craniopharyngioma, 2 chordoma, 1 nasal polyp extending into the sella, 1 neuronoma in sella, and 1 pinealoma. Six cases were malignant, including 2 malignant neuroendocrinoma in sphenoidal sinus, 1 adenoidocystic carcinoma, 1 sphenoidal sinus low differentiated carcinoma, 1 nasopharyngeal carcinoma extending into sella, 1 lung cancer metastasis to sphenoidal sinus. Clinical presentation, examination, imaging study, diagnosis and treatment were discussed. RESULTS: Among 24 cases, 18 had headache, 17 had visual symptoms. In all cases the space-occupied lesions in sphenoidal sinus and sellar area were verified by CT scan. CONCLUSIONS: 1. Headache at different levels was the commonest symptom for benign and malignant lesions. The visual loss was another common symptom. It is important to realize the relationship between visual symptom and space-occupied lesions in sphenoidal sinus and sellar area; 2. Imaging study is very important for the diagnosis of the lesions in sphenoidal sinus and sellar area; 3. It is helpful to do needle-aspirating biopsy under endoscopy to confirm the pathologic diagnosis. The benign lesions were operated on, and malignant lesions were treated by combined operation and radiation.

Adolescent↗
PubMed1998

[The diagnosis and treatment of cerebrospinal fluid rhinorrhea].

OBJECTIVE: To summarize our experience in managing cerebrospinal fluid(CSF) rhinorrhea. METHODS: Twenty-nine cases with cerebrospinal fluid rhinorrhea from 1982 to March of 1997 were reviewed. The duration of CSF rhinorrhea varied from 3 months to 23 years. The ages of the patients ranged from 7 to 72 years. RESULTS: The causes of CSF leak were spontaneous in 18 cases, traumatic in 6 (1 had two accidents and got two different leaking sites) and iatrogenic in 5 cases. Twenty-two cases underwent surgical repair. Overall closure rate was 81.8%. The causes, symptoms and signs, sites of leakage and surgical techniques were analyzed. The classification, diagnosis and treatment of CSF rhinorrhea were discussed. CONCLUSION: Transnasal extracranial repair undertaken by otorhinolaryngologist got better closure rate(93.8%) in this group. Transnasal endoscopic repair could afford excellent view, facilitate precise tissue graft placement and get better closure rate.

Adolescent↗
PubMed1998

[The normal value and clinical applications of the blink reflex].

OBJECTIVE: To study the normal value and clinical applications of blink reflex. METHODS: Using the clinical electrodiagnostic techniques, the orbital nerve was stimulated to elicit the blink reflex. RESULTS: In 20(40 sides) normal subjects, two components (R1 and R2) had been documented. The latencies were about 10.1 ms for R1, 30.4 ms and 30.7 ms separately for R2 and R2'. In 30 patients with trigeminal and facial nerve diseases and acoustic neuromas, the latencies on the affected sides were apparently longer or the reflex disappeared (P < 0.01). CONCLUSION: This study indicates that the simple, harmless electrodiagnostic measurements are of value in the initial investigation of trigeminal and facial nerve diseases and acoustic neuroma.

Adolescent↗