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1.
Innovation ; : 10-14, 2018.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-686951

RESUMO

@#BACKGROUND. Sensorineural hearing impairment (SNHI) is the most common inherited sensory defect, affecting about 3 per 1000 children. More than 50% of these patients have a genetic cause (i.e. hereditary hearing impairment; HHI). Mutations in certain genes were noted to be extraordinarily popular in the deaf patients across different populations, making molecular screening feasible for these common deafness genes. One of the most important characteristics that we have learned concerning hereditary hearing loss is that common deafness genes and their mutations are usually different according to the ethnic background. As demonstrated in our previous studies performed in Taiwanese patients, the mutation spectrums of common deafness genes, such as the GJB2 gene and the SLC26A4 gene, are different from those in the Caucasian or even other Asian populations. These findings further underscore the indispensability of the collection of local data in terms of genetic counseling. In the collaborative project, we have successfully established a cohort of >100 hearingimpaired families, and clarified the genetic epidemiology of deafness in the Mongolian population. We identified several special deafness mutations such as GJB2 c.23+1G>A, c.559_604dup, and SLC26A4 c.919-2A>G, and our results revealed that Mongolian patients demonstrate a unique genetic profile in deafness as compared to other East Asian populations (paper in preparation). Meanwhile, by organizing a seminar at National Taiwan University Hospital in March 2017, we have transferred crucial concepts and techniques regarding how to perform genetic testing for deafness to the Mongolian colleagues. In the future, we plan to strengthen the mutual collaboration by expanding the clinical cohort and upgrading the genetic examination platform using the NGS techniques.

2.
Innovation ; : 28-32, 2017.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-686888

RESUMO

@#BACKGROUND. Sensorineural hearing impairment (SNHI) is the most common inherited sensory defect, affecting about 3 per 1000 children. More than 50% of these patients have a genetic cause (i.e. hereditary hearing impairment; HHI). Mutations in certain genes were noted to be extraordinarily popular in the deaf patients across different populations, making molecular screening feasible for these common deafness genes. One of the most important characteristics that we have learned concerning hereditary hearing loss is that common deafness genes and their mutations are usually different according to the ethnic background. As demonstrated in our previous studies performed in Taiwanese patients, the mutation spectrums of common deafness genes, such as the GJB2 gene and the SLC26A4 gene, are different from those in the Caucasian or even other Asian populations. These findings further underscore the indispensability of the collection of local data in terms of genetic counseling. In the collaborative project, we have successfully established a cohort of >100 hearing-impaired families, and clarified the genetic epidemiology of deafness in the Mongolian population. We identified several special deafness mutations such as GJB2 c.23+1G>A, c.559_604dup, and SLC26A4 c.919-2A>G, and our results revealed that Mongolian patients demonstrate a unique genetic profile in deafness as compared to other East Asian populations (paper in preparation). Meanwhile, by organizing a seminar at National Taiwan University Hospital in March 2017, we have transferred crucial concepts and techniques regarding how to perform genetic testing for deafness to the Mongolian colleagues. In the future, we plan to strengthen the mutual collaboration by expanding the clinical cohort and upgrading the genetic examination platform using the NGS techniques.

3.
Innovation ; : 18-20, 2017.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-686884

RESUMO

@#BACKGROUND. Hearing loss is likely to be the most common congenital abnormality in newborns, with a reported prevalence of 1 to 2 per 1000 live births. It is vitally important to diagnose infant hearing loss or deafness at its early stages. Early detection and intervention is critical to prevent the adverse consequences of a delayed diagnosis on speech, language and cognitive development. Universal screening of hearing loss has been introduced in practice with distortion product of otoacoustic emission (DPOAE). The automated auditory brainstem response (AABR) screener is a dedicated hearing screening device which provides information not only about the outer and middle ear and cochlea but also about the auditory pathway up to the brainstem. METHODS. The study was descriptive and based on a retrospective analysis of the two year period databases (2014-2016) from the newborn hearing screening program. We have started the hearing screening from December 2012. Between 2014 to 2017 we have been screened total of 11218 newborns. We tested automated audiotory brainstem response of the newborns in their 1- 3 days of birth, using Maico MB11 Beraphone machine (German) according to the Joint Committee on Hearing Screening guidence. We assessed the test result of “pass” as “normal hearing, “refer” as to rescreen and tested again after 1 month. Infants referred again were gone to a specialist for further audio logic analysis (behavioral tests, auditory brainstem response, otoacoustic emissions and auditory steady state response). RESULTS. Our study was the first in Mongolia. Total of 10290 newborns passed bilaterally out of 11218 and 1323 referred in the first screening. For the rescreen test, 1088 out of 1134 infants resulted with “pass” and 46 infants with “refer”. For those infants, we did ABR test in their 3 and 6 months, and result of 9 children (18 ears) have bilateral profound hearing loss, 2 children (2 ears) have bilateral mixed profound hearing loss and 13 (26 ears) have bilateral profound conductive hearing loss. Coverage rate was 34,7%. First refer rate was 11,7%. Follow rate was 39,7%. We conducted the cochlear implantation surgery for 2 children out of 11. Currently, we are preparing other infants with bilateral profound hearing loss of 0-3 years old for the follow up CI surgery. CONCLUSION. In Mongolia, the data of infant hearing difficulties and prevalence of deafness is lacking. Although newborn hearing screening program has been approved in 2014 and brought opportunities to conduct universal neonatal hearing screening program. But at the moment, its only available at NCMCH which located in Ulaanbaatar city. 11 cases have a bilateral profound hearing loss out of 11218 newborns. Our study result shows similiar pattern (1.1 - 1.3 ear deafness in every 1000 birth. Lenarz et all.2008). Automated audiotory brainstem response was efficient in early identification of newborn hearing loss with high sensitivity and specification rates. Small population in the remote locations, high birth percentage, short period in the hospital after birth, lack of technology and human resources, and other factors result in higher level of referral rate newborn hearing screening and lower level of follow up and confirmation rate referals in Mongolia.

4.
Innovation ; : 13-16, 2016.
Artigo | WPRIM (Pacífico Ocidental) | ID: wpr-975527

RESUMO

There are a lot of influencing factors of facial nerve palsy; experts believe that is most likely caused by a Virus (54%) and Bacterial infections. Noninfectious causes of facial nerve palsy induce tumors (28%) and less commonly influences head trauma (18%). The retrospective analysis of WHO, in 2012. There are some cases of postoperative complication in middle ear surgery is facial nerve palsy and the total recovery outcome of function was not good. From 2013 to 2016 in EMJJ hospital, Mongolia, we enrolled 16 cases with facial nerve damaged in intratympanic canal but we could not recruit some patients with facial palsy over 6 months. Each subject was tested with pure tone test, ABR, Tympanometry. These were performed for the detection of hearing loss after Temporal bone injury. Then we also investigated location of facial nerve damages of patients by MRI and CT before reconstructive surgery. After that surgery, all patients were given corticosteroid treatment (20mg/day) and physical therapy performed such as acupuncture for a week. Study results revealed that 6 cases after 18 days, 2 cases after 30 days, 1 patient after 45 days of reconstructive surgery regained good symmetry. Therefore, we considered that, postoperative treatments like physical therapy with B12, steroid had good benefits for operation result and to shorten the recovery time. There was a patient who had damaged facial nerve in the tympanic segment during Mastoidectomy. In that case, we performed cable nerve grafting using the r.auricularismagnium but we could not recover facial nerve function. Traumatic facial nerve paralysis is the second most common type. We discussed that performing reconstruction surgery within first 3 months after intratemporal facial nerve injury is extremely desirable and more effective. In our opinion, nerve recovery might be not successfully cause of injured myelin sheet of facial nerve during middle ear surgery.

6.
Innovation ; : 32-35, 2015.
Artigo em Mn | WPRIM (Pacífico Ocidental) | ID: wpr-631226

RESUMO

Over 5% of the world’s population – 360 million people – has disabling hearing loss (328 million adults and 32 million children). Early diagnosis of hearing loss in children and providing hearing devices, including cochlear implants helps to develop speech, language, and listening skills needed for oral communication. Because of this reason, identifying children early with accurate hearing assessment in children is crucial. The aim of this study was to determine advantage of auditory steady-state response testing in comparing ABR and ASSR thresholds in children with severe hearing loss. Totally 21 children, 8 female and 13 males, aged between 18 and 46 months were included to this study. Mean age was 26 months. All the children underwent otoscopy and ABR before the measurement of ASSR thresholds. ABR and ASSR threshold measurements were performed by different physicians. They were performed in a quiet room, where sound level is less than 50 dB. Each child was asleep by nature during the test. Pearson’s correlation test have been used to evaluate correlation of thehearing thresholds of ABR and ASSR. The hearing thresholds in ABR correlated well with the threshold obtained with ASSR (Pearson’s correlation coefficient (0.231) is significant at the 0.01 level). In addition; in patients, where the thresholds for ABR were not measurable, it could be found in ASSR tests. If there is not any residual hearing for subjects, both tests resulted with no response. Based on these findings, both ABR and ASSR techniques may be used to provide an estimate of hearing sensitivity in children, but ASSR is a more valuable test than ABR. Determining thresholds for 0.5, 1, 2, 4 kHz is very important. Identifying children early with accurate hearing assessment leads to earlier fitting of sensory devices, including cochlear implants, which minimizes delays in auditory, speech, and language development.

7.
Innovation ; : 28-30, 2015.
Artigo em Mn | WPRIM (Pacífico Ocidental) | ID: wpr-631225

RESUMO

Hearing loss is likely to be the most common congenital abnormality in newborns, with a reported prevalence of 3 per 1000 live births. It is vitally important to diagnose infant hearing loss or deafness at its early stages. The automated auditory brainstem response (AABR) screener is a dedicated hearing screening device which provides information not only about the outer and middle ear and cochlea but also about the auditory pathway up to the brainstem. The data presented were collected in the well-baby nursery. Overall, data from 5857 neonates screened from December 2012 to July 2015 were analyzed in this study. During 1-3 days after birth, they were analyzed with automated auditory brainstem response (AABR). Neonates referred the screening were scheduled for repeated diagnostic evaluation within a month. And newborns referred again were sent to a specialist for further audiology analysis. Out of the 5857 babies screened, 5050 passed bilaterally and 807 referred. The number of infants referred for 2nd stage, post-discharge re-screening was 319. Of this group, 287 passed bilaterally and 32 failed the re-screening in one or both ears. Diagnostic testing was performed on all of the 32 infants who were referred. The resulting referral rate was 13.7% for first stage and 1,4% for second stage. The follow-up rate was 37%. The confirm rate was 0,13%. Profound bilateral sensor neural hearing loss was identified in 3 infants. Profound bilateral mixed hearing loss was identified in 1 infant. Automated auditory brainstem response (AABR) was efficient in the early identification of newborn and infant hearing loss with high sensitivity and specificity rates. Due to the results of the study, 3 out of 5857 infants were diagnosed with a profound hearing loss and it’s approximately close to the results of other studies and statistics.

8.
Innovation ; : 36-39, 2015.
Artigo em Mn | WPRIM (Pacífico Ocidental) | ID: wpr-975518

RESUMO

Otosclerosis is a disease that involves the cochlea and it is developed when the structure ofconnecting tissue in the area of stapedius and the oval window has changed and become unmovable.Consequently, conductive hearing loss and therefore severe sensorineural hearing loss are caused.The causes of otosclerosis have not been discovered yet but many factors impact on this disease. Anyresearch works has not been done on otosclerosis in Mongolia until now and we have conducted theresearch in 2008-2013. Therefore, we aimed to identify the hearing condition after surgery treatmentof otosclerosis.41 patients /47 ears/ who were diagnosed of having otosclerosis with conductive hearing loss, nomiddle ear infection through the comprehensive ear and hearing examinations were selected in thisstudy which was done at EMJJ Clinics between 2007 and 2013. The hearing improvement after thesurgery has been tested under bone and air conduction frequency 500, 1000, 2000, 4000, 8000 Hzand the results before and after the surgery were statistically processed on Excel 2010 and SPSS 17.0software programs. Stapedotomia and Stapedoectomia surgery approaches were applied and afteropening of attics, the hearing bones are palpated and the diagnosis of stapes otosclerosis is confirmedby the surgeon, who removes the stapes. Then a titanium K-piston (prosthese or implant) is thenplaced into this opening and connected to the malleus, or the incus.Out of 41 patients (85.4% female) involved in the study and 36 people had one ear side otosclerosisand 5 people had both ear otosclerosis. After the surgery 25 patients did not have dizziness andvomiting symptoms and 14 patients did not have dizziness with movement after 12 hours, andfor 4 patients all symptoms were disappeared after 24 hours. As for the result from the hearingexamination after 21, 60 days of the surgery, bone conduction was normal, air conduction, andhearing for 32 patients improved completely, and after 120 days of the surgery, the hearing of 33patients improved completely, bone conduction became 2000 Hz at 4000 Hz frequency 12-15 dB,average of air conduction 15,4±10,1 dB, bone-air gap 10,4±3,1 dB for 5 people, and bone conduction2000 Hz-4000 Hz, at 8000 Hz frequency 20-40dB, air conduction became 25-45dB 10,4±5,1db for 9patients and all patients had no hearing loss except for 4 people who still had tinnitus.After surgery stapedotomia and stapedoectomia for the otosclerosis, the hearing improvement was95.2% and it has been concluded that there is full possibility to perform surgeries of stapedotomia andstapedoectomia for the otosclerosis in Mongolian situation.

9.
Innovation ; : 32-35, 2015.
Artigo em Mn | WPRIM (Pacífico Ocidental) | ID: wpr-975517

RESUMO

Over 5% of the world’s population – 360 million people – has disabling hearing loss (328 million adults and 32 million children). Early diagnosis of hearing loss in children and providing hearing devices, including cochlear implants helps to develop speech, language, and listening skills needed for oral communication. Because of this reason, identifying children early with accurate hearing assessment in children is crucial. The aim of this study was to determine advantage of auditory steady-state response testing in comparing ABR and ASSR thresholds in children with severe hearing loss.Totally 21 children, 8 female and 13 males, aged between 18 and 46 months were included to this study.Mean age was 26 months. All the children underwent otoscopy and ABR before the measurement ofASSR thresholds. ABR and ASSR threshold measurements were performed by different physicians.They were performed in a quiet room, where sound level is less than 50 dB. Each child was asleep by nature during the test. Pearson’s correlation test have been used to evaluate correlation of thehearing thresholds of ABR and ASSR.The hearing thresholds in ABR correlated well with the threshold obtained with ASSR (Pearson’scorrelation coefficient (0.231) is significant at the 0.01 level). In addition; in patients, where the thresholds for ABR were not measurable, it could be found in ASSR tests. If there is not any residual hearing for subjects, both tests resulted with no response.Based on these findings, both ABR and ASSR techniques may be used to provide an estimate of hearing sensitivity in children, but ASSR is a more valuable test than ABR. Determining thresholds for 0.5, 1, 2, 4 kHz is very important. Identifying children early with accurate hearing assessment leads to earlier fitting of sensory devices, including cochlear implants, which minimizes delays in auditory, speech, and language development.

10.
Innovation ; : 28-30, 2015.
Artigo em Mn | WPRIM (Pacífico Ocidental) | ID: wpr-975516

RESUMO

Hearing loss is likely to be the most common congenital abnormality in newborns, with a reported prevalence of 3 per 1000 live births. It is vitally important to diagnose infant hearing loss or deafness at its early stages. The automated auditory brainstem response (AABR) screener is a dedicated hearing screening device which provides information not only about the outer and middle ear and cochlea but also about the auditory pathway up to the brainstem.The data presented were collected in the well-baby nursery. Overall, data from 5857 neonates screened from December 2012 to July 2015 were analyzed in this study. During 1-3 days after birth, they were analyzed with automated auditory brainstem response (AABR). Neonates referred the screening were scheduled for repeated diagnostic evaluation within a month. And newborns referredagain were sent to a specialist for further audiology analysis.Out of the 5857 babies screened, 5050 passed bilaterally and 807 referred. The number of infantsreferred for 2nd stage, post-discharge re-screening was 319. Of this group, 287 passed bilaterally and 32 failed the re-screening in one or both ears. Diagnostic testing was performed on all of the 32 infants who were referred. The resulting referral rate was 13.7% for first stage and 1,4% for second stage. The follow-up rate was 37%. The confirm rate was 0,13%. Profound bilateral sensor neural hearing loss was identified in 3 infants. Profound bilateral mixed hearing loss was identified in 1 infant.Automated auditory brainstem response (AABR) was efficient in the early identification of newborn and infant hearing loss with high sensitivity and specificity rates. Due to the results of the study, 3 out of 5857 infants were diagnosed with a profound hearing loss and it’s approximately close to the results of other studies and statistics.

11.
Innovation ; : 10-12, 2015.
Artigo em Mn | WPRIM (Pacífico Ocidental) | ID: wpr-975512

RESUMO

Among world population, 23.4% have different kinds of hearing disorders and 56% are middle ear disorders, 30% are inner ear disorder, 10% are congenital deaf and 4% are congenital mixed outer and middle ear disorder (WHO info, 2006).In 1995, by the German research, 2% of newborn babies were deaf therefore, among children from 1-18, 16% had middle ear disorder and 0.8% had inner ear disorder. In most cases (54%) cause of hear loss and deaf as sound transmitting apparatus. Later in 2010, sound transmitting apparatus related disorder was decreased by 22.4% J.Helms1995 , K.Schwager 2010 . Doctors proved that 62% of sound transmitting apparatus related disorders are middle ear diseases, 16,2% out of the diseases have the defect of malleus, 44,1 % have the defect of incus and discontinuity of incus and stapedius, and 39,7% is totally absent of ossicular chain 120 tympanoplasty III type surgeries were operated in 2011-2013 in Mongolia. Clinical and operative features of the tympanoplasty III type surgeries were prospectively recorded. Aim: To recover sound transmitting related hear loss with titan prosthesis implant. 120 tympanoplasty III type surgeries were operated in 2011-2013 in Mongolia. Clinical and operative features of the tympanoplasty III type surgeries were prospectively recorded. Out of the surgeries, 51 cases (42.5%) were cholesteatoma, 53 cases (44.2%) were granuloma middle ear and 16 cases (13.3%) were adhesive otitis media. The air and bone gap of all patients were above 15-35 dB. HEINZKURZ firm’s TTP-Variac system’s titan prosthesis was used. Titan prosthesis PORP was carried out in 86 cases (71.6%). For 40 (45.5%) out of the 86 cases, size of titan prosthesis PORP 2.25 mm was chosen. Hearing level increased for 72% out of patients by 10-25 dB after the operation. However, for 46 (54.5%) out of the 86 cases, size of titan prosthesis PORP 2.5 mm was chosen. Hearing level increased for 82% out of patients by 10-30 dB after the operation. Titan prosthesis TORP size 4-4.25 mm waschosen for 34 (28.4%) out of 120 cases. Hearing level increased by 10-30 dB for 80% out of patients involved after the operation Out of the surgeries, 51 cases (42.5%) were cholesteatoma, 53 cases (44.2%) were granuloma middleear and 16 cases (13.3%) were adhesive otitis media.Titan prosthesis PORP was carried out in 86 cases (71.6%). For 40 (45.5%) out of the 86 cases, size oftitan prosthesis PORP 2.25 mm was chosen. Hearing level increased for 72% out of patients by 10-25 dB after the operation. However, for 46 (54.5%) out of the 86 cases, size of titan prosthesis PORP 2.5 mm was chosen. Hearing level increased for 82% out of patients by 10-30 dB after the operation. Titan prosthesis TORP size 4-4.25 mm was chosen for 34 (28.4%) out of 120 cases. Hearing level increased by 10-30 dB for 80% out of patients involved after the operation. Implantation of Titanium prosthesis increased hearing capability by 80% dB. We drum cover the cartilage and cartilage film is used to by Canal wall down, Canal wall updone. Hearing level decrease d by patients involved after the operation. Implantation of Titanium prosthesis increased hearing capability by 80% dB. The air transfer of more than35 dB air-bonegapofmorethan15dB we observed defect of hearing bone

12.
J Vet Pharmacol Ther ; 33(1): 50-5, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20444025

RESUMO

Medetomidine is a well-established sedative and analgesic for dogs and cats. As a premedicant for anesthesia regimens that also include other agents, medetomidine can also provide a dose-sparing effect. While there are likely several reasons for the dose-sparing effect of medetomidine, the role of metabolic drug-drug interactions at the single enzyme level has not yet been examined. Using a panel of individually expressed canine cytochromes P450 cloned from beagle liver, this report demonstrates that medetomidine is an extremely potent CYP2B11 inhibitor (IC(50) < 10 nm) and that ketamine and midazolam are CYP2B11 substrates with high intrinsic clearances. These in vitro findings suggest that under some circumstances, medetomidine (i.e. 'perpetrator') may inhibit the metabolic clearance of some high metabolic clearance drugs (i.e. 'victims') with which it is commonly co-administered via the CYP2B11 pathway. However, as the dose-sparing effect of medetomidine premedication commonly results in anesthetic dose reduction, any increased plasma concentrations of victim drugs caused by medetomidine would still be lower than if no dose reduction had been made. Further studies are needed to characterize whether medetomidine possesses the potential to cause pharmacokinetic interactions. In conclusion, the ability of recombinant P450s to define canine-specific drug clearance pathways and P450 inhibitors should prove useful in identifying drug combinations that may require dose adjustments in dogs.


Assuntos
Anestésicos/farmacologia , Hidrocarboneto de Aril Hidroxilases/antagonistas & inibidores , Hidrocarboneto de Aril Hidroxilases/metabolismo , Cães/metabolismo , Hipnóticos e Sedativos/farmacologia , Esteroide Hidroxilases/antagonistas & inibidores , Esteroide Hidroxilases/metabolismo , Animais , Clonagem Molecular , Família 2 do Citocromo P450 , Concentração Inibidora 50
13.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-975878

RESUMO

Introduction:According to studies range by the World Health Organization in 2010, 278 million people are deaf or hearing impairment, out of which 24% use an hearing aid and one out of every 10 people has been treated with surgical method and 9 people’s hearing loss has been restored using acoustic treatment method.Purpose:Our purpose is to define noisy vowels of Mongolian word, which will be used for configuration of hearing aid, thereby improve hearing ability.The objectives1. Analyze spectrogram for noisy sound of Mongolian word and define frequency and level of noisy words.2. Define average difference of listening level of the noisy sounds of Mongolian language using “Listening field of Mongolian word”Materials and method:We did the spectrogram for noisy sounds of the Mongolian word using voices of 62 people including male and female children as well as adults. Also, we analyzed frequency energy of all vowels noted in the 60-65 dB computer, via the “PRAAT” software, which defines analysis of speech in phonetics and studied listening level of the strong vowels using listening sphere of word.Result:During our studies, we selected the vowels [a], [e], [u], [o] [a], [ʊ], [ɔ], [i] and defined spectrogram and energy concentration (formant) of each vowel to define the vowels with the highest energy, and further found out that distance difference of the spectrogram of each vowel and frequency between vowels as 300-780 Hz. On the other hand, difference between spectrogram of each strong sound such as [sh], [s], [v], [z], [dj], [kh] has been defines as 340-2800 dB.When we observed the words with strong sound in the listening field of Mongolian words, which were 3- 5 dB lower than the clearer words.Conclusion:1. According to spectrogram, noisy sound [sh], [s], [z], [dj] has frequency of 3300Hz-3500Hz, which is noisier and resulted in poor acoustic listening ability. Further, we found out that Distant difference of vowels of Mongolian language [a], [e], [o] and consonants [m], [n] is far, accordingly, acoustic listening ability has been good, on the other hand, distant difference of vowels of Mongolian word [ʊ], [ɔ], [u] is near or close, accordingly, acoustic listening ability has been not well.2. Level of distinquishment of the noisy sounds of Mongolian word has been lower by 3.6+ 0.8Db to 5.2+1.2Db at levels of clear sound to feedback.

14.
J Med Chem ; 44(26): 4716-32, 2001 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-11741489

RESUMO

5,6-Dimethoxy-2-(N-dipropyl)-aminoindan (3, PNU-99194A) was found to be a selective dopamine D(3) receptor antagonist with potential antipsychotic properties in animal models. To investigate the effects of nitrogen substitution on structure-activity relationships, a series of 5,6-dimethoxy-N-alkyl- and N-alkylaryl-substituted 2-aminoindans were synthesized and evaluated in vitro for binding affinity and metabolic stability. The results indicate that substitution at the amine nitrogen of the 2-aminoindans is fairly limited to the di-N-propyl group in order to achieve selective D(3) antagonists. Thus, combinations of various alkyl groups were generally inactive at the D(3) receptor. Although substitution with an N-alkylaryl or N-alkylheteroaryl group yields compounds with potent D(3) binding affinity, the D(2) affinity is also enhanced, resulting in a less than 4-fold preference for the D(3) receptor site, and no improvements in metabolic stability were noted. A large-scale synthesis of the D(3) antagonist 3 has been developed that has proven to be reproducible with few purification steps. The improvements include the use of 3,4-dimethoxybenzaldehyde as a low-cost starting material to provide the desired 5,6-dimethoxy-1-indanone 5c in good overall yield (65%) and the formation of a soluble silyl oxime 17 that was reduced efficiently with BH(3).Me(2)S. The resulting amino alcohol was alkylated and then deoxygenated using a Lewis acid and Et(3)SiH to give the desired product 3 in good overall yield of ( approximately 65%) from the indanone 5c.


Assuntos
Antagonistas de Dopamina/síntese química , Indanos/síntese química , Receptores de Dopamina D2/efeitos dos fármacos , Animais , Ligação Competitiva , Células CHO , Divisão Celular/efeitos dos fármacos , Cricetinae , Antagonistas de Dopamina/química , Antagonistas de Dopamina/farmacologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Técnicas In Vitro , Indanos/química , Indanos/farmacologia , Masculino , Atividade Motora/efeitos dos fármacos , Ensaio Radioligante , Ratos , Ratos Sprague-Dawley , Receptores de Dopamina D3 , Relação Estrutura-Atividade
15.
Skin Pharmacol ; 8(5): 221-8, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8527153

RESUMO

The purpose of this study was to determine if the penetration enhancer SEPA (2-n-nonyl-1,3-dioxolane) would augment the scalp hair growth effects of topical minoxidil in the balding stumptail macaque. A 1-in2 area on the balding scalp of 40 adult female monkeys (four drug-treated and four vehicle-treated groups of 5 monkeys each) was topically treated 5 days/week, q.d. or b.i.d., with approximately 250 microliters of minoxidil-SEPA (2.5% minoxidil, weight/volume in 10% SEPA, 25% propylene glycol and 65% isopropyl alcohol), Rogaine topical solution (TS, 2% minoxidil, weight/volume in 20% propylene glycol, 60% ethanol and 20% water) or respective vehicles (without drug) for 16 weeks via paintbrush application. Scalp hair was collected by shaving and vacuuming the dosed area at baseline and at 4-week intervals. The shaved hair was filtered, weighed and recorded as the change from baseline. The q.d. and b.i.d. minoxidil-SEPA groups displayed a significant increase in hair weight compared to their respective vehicles at week 4 whereas q.d. and b.i.d. Rogaine TS groups were not active until week 8 and 12, respectively. Both minoxidil-SEPA treatments produced significantly greater cumulative hair weight over the entire 16-week study compared to either of the Rogaine TS treatments. Comparable increases in cumulative hair weight were evident between q.d. and b.i.d. minoxidil-SEPA groups and between q.d. and b.i.d. Rogaine TS groups.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Alopecia/tratamento farmacológico , Cabelo/efeitos dos fármacos , Minoxidil/farmacologia , Couro Cabeludo/efeitos dos fármacos , Administração Tópica , Animais , Sistemas de Liberação de Medicamentos , Feminino , Macaca mulatta , Fatores de Tempo
16.
J Assoc Off Anal Chem ; 74(3): 471-5, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1831449

RESUMO

A new microbiological method, identified as the spectinomycin trifluoroacetic (SPE-TFA) method, was compared with the current AOAC method for analyzing spectinomycin in meal and pelleted feeds fortified with LS-20 premix. Feeds containing 3 concentrations of drugs and a zero level were tested in a correlation study. The data showed no significant differences in the percent of theory assayed between meal and pelleted samples using the SPE-TFA method, but the percent of theory found using the AOAC method was significantly lower for the pelleted samples than for the meal samples. The within-sample variation of the AOAC assay was also not the same for all samples; the SPE-TFA assay variation was relatively constant for all samples. The SPE-TFA method produced an overall average recovery of 98% with a range of 89-109% compared with an 85% recovery ranging from 64 to 102% for the AOAC method. In addition to producing better recoveries, the SPE-TFA method features a more sensitive response line, and final test solutions have viscosities and clarity more comparable to the standard solutions than those produced by the current AOAC method.


Assuntos
Ração Animal/análise , Espectinomicina/análise , Bioensaio , Escherichia coli/efeitos dos fármacos , Indicadores e Reagentes , Lincomicina/análise , Espectinomicina/farmacologia , Ácido Trifluoracético
17.
J Vet Pharmacol Ther ; 13(3): 270-7, 1990 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2231867

RESUMO

Eighteen normal cats were randomly allocated into two blocks with three treatment groups and dosed orally with clindamycin aqueous solution for 10 days at a dosage rate of 5.5 mg/kg twice daily (Group 1), 11 mg/kg twice daily (Group 2), or 22 mg/kg once daily (Group 3). At the end of dosing, all cats were killed and tissues were taken for clindamycin concentration analysis. Clindamycin was extracted from tissues using solid-phase extraction columns followed by microbiological assay of clindamycin using a cylinder plate assay using M. luteus. Recovery from each tissue was determined by inoculating known concentrations of clindamycin into drug-naive tissues and comparing the observed concentration from the expected concentration. Confirmation that the bioassay detected clindamycin and not N-desmethylclindamycin, its active metabolite, was done using gas-chromatography-mass-spectrometry. Concentrations were highest in the lung, with tissue:serum ratios greater than 3 in all groups. Concentrations were higher in Group 3 than Group 1 (P less than 0.05). Only liver concentrations in Group 3 were statistically higher than in Group 2, although all tissues except bone marrow and CSF had numerically higher concentrations in Group 3 than Group 2. The tissue:serum ratio was greater than 1 in all tissues studied except bone, cerebrospinal fluid, brain, and skeletal muscle.


Assuntos
Gatos/metabolismo , Clindamicina/farmacocinética , Administração Oral , Animais , Clindamicina/administração & dosagem , Feminino , Masculino , Distribuição Aleatória , Distribuição Tecidual
18.
J Vet Pharmacol Ther ; 12(2): 209-16, 1989 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2746726

RESUMO

Eighteen normal cats were randomly allocated into three treatment groups and dosed with clindamycin aqueous solution for 10 days at a dosage rate of: (1) 5.5 mg/kg b.i.d.; (2) 11 mg/kg b.i.d.; or (3) 22 mg/kg once daily. Serum disposition of clindamycin was determined after the first and last dose of clindamycin was given, and was analyzed using model-independent pharmacokinetics by both the trapezoidal rule method and the predictive equation method. Complete blood counts and clinical chemistries were determined before and after the study. The trapezoidal rule method produced similar mean results with much less variance than the predictive equation method. Mean residence time was longer (P less than 0.05) after the high dose (393 +/- 77 min) than after either the low or medium doses (276 +/- 51 and 274 +/- 45 min, respectively). Oral volume of distribution (Vd(ss)/F) after the high dose (3.06 +/- 0.92 l/kg) was larger (P less than 0.05) than that after the low or medium doses (1.62 +/- 0.30 and 1.76 +/- 0.53 l/kg, respectively). Oral Vd(ss)/F was significantly smaller (P less than 0.001) after the last dose than after the first dose when analyzed by treatment group. Significant (P less than 0.01) decreases in the leukogram and erythrogram were observed, due to the large amount of blood collected for drug analysis. No clinical signs of drug intoxication were observed, and no drug-related necropsy findings were found.


Assuntos
Gatos/metabolismo , Clindamicina/farmacocinética , Administração Oral , Animais , Contagem de Células Sanguíneas/veterinária , Análise Química do Sangue , Clindamicina/administração & dosagem , Clindamicina/sangue , Feminino , Masculino , Distribuição Aleatória , Fatores de Tempo
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