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K Schmitt

Publications and source records attributed to K Schmitt.

At least 37 records · Page 2Linked to original sources
PubMed1998

Genome scan of European-American schizophrenia pedigrees: results of the NIMH Genetics Initiative and Millennium Consortium.

The Genetics Initiative of the National Institute of Mental Health (NIMH) was a multisite study that created a national repository of DNA from families informative for genetic linkage studies of schizophrenia, bipolar disorder, and Alzheimer's disease. The schizophrenia families were collected by three sites: Washington University, Harvard University, and Columbia University. This article, one in a series that describes the data collected for linkage analysis by the schizophrenia consortium, presents the results for the European-American sample. The European-American sample comprised 43 nuclear families and 146 subjects. Ninety-six of the family members were considered affected by virtue of having received a DSM-III-R diagnosis of schizophrenia (N = 82) or schizoaffective disorder, depressed (N = 14). The families contained a total of 50 independent sib-pairs. Using the significance threshold criteria suggested by Lander and Kruglyak [(1995): Nat Genet 241-247], no region showed statistically significant evidence for linkage; two markers on chromosome 10p showed statistical evidence suggestive of linkage using the criteria of Lander and Kruglyak [(1995): Nat Genet 241-247]: D10S1423 (nonparametric linkage (NPL) Z = 3.4, P = .0004) and its neighbor, D10S582 (NPL Z = 3.2, P = .0006).

Adolescent↗
PubMed1998

BCG lymphadenitis in an HIV-infected child 9.5 years after vaccination.

Complications of Bacillus Calmette-Guerin (BCG) vaccination have been reported in immunocompetent as well as in immunocompromised individuals. Severe and/or late complications have been associated with impairment of cell-mediated immunity. A case of BCG lymphadenitis in a vertically infected HIV-positive boy 9.5 years after vaccination is presented. The vaccination was performed within the first week of life, the HIV status of the mother being unknown. When the boy was 2.5 years old, his HIV infection was diagnosed after his mother had died from AIDS. At that time his CD4 count was 739 cells/microL. In the course of the following years, his CD4 count declined steadily, until it reached a low of about 20 cells/microL at the age of 5.5 years. He was troubled with recurring respiratory infections and one incidence of severe pancreatitis. Apart from that, he was in stable condition and led a more or less normal life. At the age of 9.5 years he developed lymphadenitis in his left axilla. The node was examined via biopsy, and the appropriate tests showed an infection with Mycobacterium bovis BCG variety. The CD4 count at that time was 16 cells/microL, polymerase chain reaction showed 220,000 RNA copies/mL. There were no signs of dissemination. Antitubercular agents were administered, and an antiretroviral combination therapy was started. The patient was discharged from the hospital after approximately 2 months. After an uneventful period of 9 months, the boy, still on antitubercular medicine, exhibited a secreting fistula in his left axilla, again due to Mycobacterium bovis, BCG variety. The fistulous tissue was removed surgically, and the antitubercular treatment was given intravenously for almost 3 months before being changed to an oral application. In addition, the antiretroviral regimen was completely exchanged. The case presented illustrates that there is a risk of very late complications in HIV-infected individuals, even when they are vaccinated when they are asymptomatic newborns. Although the risk seems low, one has to be aware of the problem because timely treatment is probably essential to prevent dissemination of the infection. Late complications of BCG vaccinations are most likely to be detected in countries with high medical standards, where HIV-infected children are surviving for longer periods of time.

Antitubercular Agents↗
PubMed1998

Doxycycline and azithromycin for prevention of chlamydial persistence or recurrence one month after treatment in women. A use-effectiveness study in public health settings.

BACKGROUND: To treat chlamydial infection, the Centers for Disease Control and Prevention recommends either a single dose of azithromycin or a 7-day course of doxycycline. Cost is a concern with the single-dose regimen; compliance is a concern with the multidose regimen. GOAL: To compare the use-effectiveness of azithromycin and doxycycline for preventing persistence or recurrence of Chlamydia trachomatis infection in women and to evaluate associated risk behaviors. STUDY DESIGN: One hundred and ninety-six chlamydia-infected women and their sex partners were recruited into a randomized controlled trial of single-dose versus multidose regimens in seven public health clinics, with no incentives for enrollment, compliance, or follow-up. The outcome, measure was a positive test for C. trachomatis by polymerase chain reaction testing at 1 month after treatment. RESULTS: C. trachomatis positivity at 1 month was similar for women receiving single-dose (5.1%, 5/98) and multidose therapy (4.1%, 4/98). Reported compliance among 73 women taking multidose therapy was 94.5%. A twofold to threefold increased risk of chlamydial persistence or recurrence was observed among women who were < or = 24 and white or who reported: a recent new partner, multiple partners, or a partner who may have had multiple partners at the time of enrollment or that not all partners were treated during the 1-month follow-up period after initiation of treatment. CONCLUSIONS: The use-effectiveness of single-dose and multidose therapy was comparably high. Observed rates of persistence or recurrence were consistent with reported rates of pharmacological treatment failure. However, all women with C. trachomatis detected at 1 month had behavioral risk factors that may have contributed to reinfection.

Adolescent↗
PubMed1998

Norplant selection and satisfaction among low-income women.

OBJECTIVES: This study examined correlates of Norplant selection and satisfaction among low-income women. METHODS: Interviews were completed in family planning clinics in 4 Florida counties with 1152 Norplant users and 1268 nonusers, with follow-up interviews with a subsample up to 1 year later. Logistic regression models estimated the associations of socio-demographic and medical characteristics with Norplant selection and method satisfaction. RESULTS: Odds ratios for Norplant selection were significantly greater among women who planned to have children in 5 or more years, those who were "offered" Norplant, those who lived in Palm Beach County, those who were using drugs, and those who were Medicaid clients. Women younger than 17 and those who learned about Norplant from a friend were twice as likely as others to select Norplant. Ninety-two percent of Norplant users were satisfied with the method; women with side effects and those who felt pressure to select a method were significantly less likely than others to be satisfied. CONCLUSIONS: Norplant provides an acceptable and satisfying method of birth control for many low-income women. Proper counseling about all methods of birth control and about Norplant's side effects remains critical to the appropriate delivery of this method.

Adolescent↗
PubMed1997

The influence of growth hormone monotherapy and growth hormone in combination with oxandrolone or testosterone on thyroxid hormone parameters and thyroxine binding globulin in patients with Ullrich-Turner syndrome.

UNLABELLED: Administration of human growth hormone (GH) has yielded conflicting results concerning its role on thyroid function in patients with Ullrich-Turner syndrome. Therefore, we investigated the course of thyroid hormone parameters and thyroxin binding globulin in relation to GH therapy, IGF-I and additional oxandrolone-(Ox) or testosterone (T) treatment in 20 patients with Ullrich-Turner syndrome. During the 1st year the patients received only GH. There was no change in T4, fT4, and TSH levels, T3 increased significantly (P < 0.01) after 6 and 12 months, resulting in a higher T3/T4 ratio. TBG (P < 0.05) and IGF-I (P < 0.01) increased after 6 months and remained elevated at 12 months. A significant positive correlation was found between the change of T4 and TBG after 6 months (r = 0.47, P < 0.05) and after 12 months (r = 0.69, P < 0.005). Thirteen patients were further investigated after addition of an anabolic compound; 7 received Ox (0.0625 mg/kg/day po) and 6 low dose T (5 mg i.m. every 14 days). Chronological age was comparable in these groups (10.7 +/- 2.7 vs 10.7 +/- 3.6 years). After 6 months of combination therapy with Ox, T4, T3 and TSH decreased. As T4 and T3 showed a parallel decrease the T3/T4 ratio remained elevated. TBG declined after 6 and 12 months (P < 0.05), while IGF-I showed a further increment (P < 0.05). There was no correlation between the changes in T4 and IGF-I, TSH and TBG, respectively. In the T-treated group only IGF-I increased (P < 0.05) to the same extent as in the Ox-treated patients, whereas the thyroid parameters did not change. CONCLUSION: The observed changes in thyroid hormone and TBG levels in the Ox group were not mediated by GH or IGF-I. The Ox-induced TBG decrease might be linked to altered pancreatic functions regulating carbohydrate metabolism.

Adolescent↗
PubMed1997

Short- and long-term (final height) data in children with normal variant short stature treated with growth hormone.

UNLABELLED: Seventeen children with normal variant short stature and a predicted height below -2 SDS were treated with growth hormone (GH) six times a week for a period of 5 years. Patients were randomly selected to receive three different doses of GH, group 1 (n = 6) 3 IU/m2 per day, group 2 (n = 6) 4.5 IU/m2 per day and group 3 (n=5) 3 IU/m2 per day in the 1st year and 4.5 IU/m2 per day thereafter. There was a significant increase in height after 1 and 2 years for all patients and for all subgroups. However, this increase was not dependent on GH dose. The decrease in height velocity during the 2nd year was not prevented by the increase of GH dose in group 3. The change of predicted height after 2 years was +0.75 SDS (according to Tanner Whitehouse). Fourteen children have been treated for 4 years and 8 children for 5 years without a further change in height prediction. Nine patients have reached final height which was 2.4 cm (+0.41 SDS) above pretreatment height prediction. Final height was nearly identical to predicted height after 1 year of therapy. CONCLUSION: An increment in height prediction was observed during the first 2 years of GH treatment and maintained thereafter. However, there was only a minor increase in final height over predicted height which does not justify the general use of GH in children with normal variant short stature.

Adolescent↗
PubMed1997

[Effect of panretinal photocoagulation on the ocular pulse curve].

BACKGROUND: Most studies on the effects of panretinal photocoagulation (PRPC) on ocular circulation are concerned with retinal circulation. In the present study, we examined the ocular pulse curve after PRPC and determined pulsatile ocular blood flow (an indicator of choroidal circulation) and ocular perfusion pressure. PATIENTS AND METHOD: In 10 patients with diabetes mellitus (8 with type II and 2 with type I; mean age 64 yrs) and severe, hitherto untreated, bilateral proliferative diabetic retinopathy, an intensive unilateral PRPC with 1500 argon laser burns (spot size: 500 mu) was performed in 2 sessions (interval: 3 wks). Before and-in 3-wk intervals-up to 9 wks after onset of treatment, an ocular pulse curve was recorded using oculo-oscillo-dynamography, and the following variables were determined: ocular pulsation amplitude (OPA), pulsatile ocular blood flow (POBF), systolic ophthalmic artery pressure (SOAP), and systolic ocular perfusion pressure (SOPP). RESULTS: PRPC led to a reduction of OPA and POBF in relation to the untreated contralateral eyes. 3 wks after the 1st coagulation, the reduction averaged 20% (OPA) and 19.1% (POBF). The maximum reduction was found 9 wks after onset of treatment (6 wks after the 2nd coagulation) and amounted to 29.9% and 29.2%, respectively. The differences between photocoagulated and untreated eyes were highly significant on average (P < 0.01; ANOVA) as well as for the time course (P < 0.001). SOAP and SOPP were not changed significantly during PRPC. CONCLUSIONS: OPA and POBF are determined by the cardiac cycle-related intraocular volume changes depending predominantly on choroidal blood flow. Thus, the reduction of POBF after PRPC is indicative of a lowered pulsatile choroidal blood flow. The morphological substrate is probably the choriocapillaries closure after photocoagulation described in the literature.

Adolescent↗
PubMed1997

CYP11B1 mutations causing non-classic adrenal hyperplasia due to 11 beta-hydroxylase deficiency.

Steroid 11 beta-hydroxylase deficiency is the second most common cause of congenital adrenal hyperplasia, the inherited inability to synthesize cortisol. Severely affected patients carry mutations in the CYB11B1 gene that destroy enzymatic activity. Such patients have signs of androgen excess and usually have hypertension. Mild or non-classic 11 beta-hydroxylase deficiency has been reported previously but not studied genetically. In this study we report analysis of the CYP11B1 genes of three patients thought to suffer from non-classic 11 beta-hydroxylase deficiency. Mutations were detected in the CYP11B1 genes of two patients. One was a compound heterozygote for missense mutations N133H and T319M, whereas the other carried a nonsense mutation (Y423X) on one allele and a missense mutation (P42S) on the other. All three missense mutations affected enzymatic activity when expressed in vitro. No mutations were detected in the coding regions or intron-exon boundaries of the CYP11B1 genes of the other putative non-classic patient. In addition, we were unable to detect CYP11B1 mutations in two hirsute women with mildly elevated levels of 11 beta-hydroxylase precursors who had previously been identified in a screening study of patients in a reproductive endocrinology clinic. We conclude that nonclassic 11 beta-hydroxylase deficiency is a rare disorder. It is not a significant cause of hyperandrogenism in women and relatively stringent criteria should be used to prevent its misdiagnosis.

Adrenal Glands↗
PubMed1997

A first-generation whole genome-radiation hybrid map spanning the mouse genome.

We have assembled a first-generation anchor map of the mouse genome using a panel of 94 whole-genome-radiation hybrids (WG-RHs) and 271 sequence-tagged sites (STSs). This is the first genome-wide RH anchor map of a model organism. All of the STSs have been previously localized on the genetic map and are located 8.8 Mb apart on average. This mouse WG-RH panel, known as T31, has an average retention frequency of 27.6% and an estimated potential resolution of 145 kb, making it a powerful resource for efficient large-scale expressed sequence tag mapping. [All of the mapping data for the maps presented here have been deposited at the Research Genetics, Inc., web site and can be freely accessed and downloaded at http://www.resgen.com/.]

Animals↗
PubMed1997

Short- and long-term (final height) growth responses to growth hormone (GH) therapy in patients with Turner syndrome: correlation of growth response to stimulated GH levels, spontaneous GH secretion, and karyotype.

In 41 girls with Turner syndrome, the growth hormone (GH) peak values during stimulation tests and parameters of spontaneous nocturnal GH secretion were studied and compared with respect to different karyotypes, short-term growth response to GH therapy, and final height. 22.0% of the girls tested had a subnormal (peak < 11 ng/ml) and 9.7% a pathological (< 7 ng/ml) GH response. The spontaneous GH secretion showed a good correlation with the data of the provocation tests, providing no further information regarding GH capacity. Short-term growth response to GH treatment could not be predicted by any of the investigated parameters. Although patients with isochromosomes had frequent subnormal GH tests, their growth response to GH treatment after 1 year was comparable to that of girls with XO karyotype and mosaicism. In 18 patients who had reached final height, the height gain during treatment (calculated as final height minus projected adult height) was not different among patients with normal, subnormal, or pathological GH tests. In contrast, final height minus projected adult height in 4 girls with isochromosomes was 15.7 +/- 5.1 versus 7.6 +/- 3.3 cm in 14 patients with other karyotypes (p < 0.01). These girls had a more pronounced bone age delay (3.3 +/- 0.3 vs. 1.8 +/- 1.2 years) at the start of therapy and thus a better growth potential. We conclude that short- and long-term growth responses to GH treatment in Turner syndrome could not be predicted by GH testing. Patients with isochromosomes might represent a subpopulation which is more frequently GH deficient and shows a marked bone age delay.

Adolescent↗
PubMed1996

A gene map of the human genome.

The human genome is thought to harbor 50,000 to 100,000 genes, of which about half have been sampled to date in the form of expressed sequence tags. An international consortium was organized to develop and map gene-based sequence tagged site markers on a set of two radiation hybrid panels and a yeast artificial chromosome library. More than 16,000 human genes have been mapped relative to a framework map that contains about 1000 polymorphic genetic markers. The gene map unifies the existing genetic and physical maps with the nucleotide and protein sequence databases in a fashion that should speed the discovery of genes underlying inherited human disease. The integrated resource is available through a site on the World Wide Web at http://www.ncbi.nlm.nih.gov/SCIENCE96/.

Amino Acid Sequence↗
PubMed1996

Construction of a radiation hybrid map of chromosome 9p.

A radiation hybrid panel has been constructed for chromosome 9 using the somatic cell hybrid GM10611 as the donor cell line fused to the hamster cell line A23. The hybrid GM10611 was characterized by fluorescence in situ hybridization and reverse painting onto spreads of normal human metaphase chromosomes; it contains human chromosome 9 as the only cytogenetically detectable human material. GM10611 was irradiated with 6000 rads of X rays prior to fusion, a total of 93 independent clones were selected, and frozen stocks and DNA were prepared from each clone. These clones were screened by PCR amplification with oligonucleotide primers for sequence-tagged sites specific for 50 single-copy loci mapping to the short arm of chromosome 9. The average retention frequency of these hybrids was approximately 23%. The markers were ordered into a framework map by analyzing coretention patterns, minimizing the number of obligatory chromosome breaks, and finally confirming the order by maximum likelihood methods. A framework map ordering 27 markers with odds greater than 1000:1 was constructed. A further 16 markers that could not be uniquely placed on the map with the required support were positioned within a range of adjacent intervals.

Animals↗
PubMed1996

Construction of a mouse whole-genome radiation hybrid panel and application to MMU11.

Whole-genome radiation hybrids have been used to construct human genome maps that integrate different types of markers. To investigate this methodology in mammalian species other than humans, a panel of 164 mouse x hamster whole-genome radiation hybrids was constructed. This set of hybrids was used to produce a high-resolution map of a region on MMU11 that included microsatellite markers and cDNA sequences. The mouse homologue of the human SRY-related gene SOX9 was mapped to an interval of approximately 1.1 cM flanked by the microsatellite markers D11Mit11 and D11Mit291. This interval includes the region containing the mouse Tail-short mutation, a possible homologue of the human syndrome campomelic dysplasia, which is caused by mutations in SOX9. Our results suggest that whole-genome radiation hybrid technology will be a useful adjunct to mapping the genomes of nonhuman mammalian species.

Animals↗
PubMed1996

All-trans retinoic acid and short-time, high-dose cytarabine in two children with acute promyelocytic leukemia.

We report on two girls, 3 and 13 years old, with acute promyelocytic leukemia (APL) who were successfully treated with all-trans retinoic acid (ATRA) 45 mg/m2/day. "Retinoic acid syndrome" was prevented with short-time treatment of high dose (4 x 1.5 g/m2) cytarabine. This regimen was well tolerated, although both children were critically ill. They achieved a complete remission confirmed by light microscopy, but reverse transcriptase polymerase chain reaction remained positive after ATRA, underlining the need of further chemotherapy.

Adolescent↗
PubMed1996

Regional assignment of human ESTs by whole-genome radiation hybrid mapping.

The UK HGMP Resource Centre's collection of human partial cDNA sequences (ESTs) have been examined for suitability for mapping by PCR on a panel of somatic cell hybrids. The chromosomal assignments of 92 ESTs were determined with a monochromosomal hybrid panel, and a subset of 45 were linked to genetic markers with a panel of whole-genome radiation hybrids (WG-RHs). These results demonstrate the potential of WG-RHs to construct a transcript map of the human genome.

Base Sequence↗
PubMed1996

Spontaneous closure of the human fetal ductus arteriosus--A cause of fetal congestive heart failure.

OBJECTIVE: Closure of the fetal ductus arteriosus, which is usually due to nonsteroidal antiinflammatory agents, may be detrimental. Therefore prenatal and postnatal clinical and echocardiographic findings in four human fetuses with spontaneous ductus arteriosus occlusion are reported. STUDY DESIGN: Echocardiographic and clinical data were retrospectively analyzed. RESULTS: Spontaneous closure of the ductus arterious was discovered in four fetuses (gestational age 34 to 38 weeks). No mother had received nonsteroidal antiinflammatory agents. Enlargement of the right heart and pulmonary arteries and tricuspid and pulmonary regurgitation were present in all cases. Two fetuses had right ventricular hypertension. Postnatally their right ventricular function recovered promptly. The others had severe right heart failure with abnormal umbilical venous pulsations. After immediate delivery none had signs of persistent pulmonary hypertension. However, they have echocardiographic evidence of right ventricular dysfunction 2 to 6 months after delivery. CONCLUSIONS: Occlusion of the fetal ductus arteriosus may also occur in the absence of treatment with nonsteroidal antiinflammatory agents. Immediate delivery resulted in good clinical outcome, although right ventricular dysfunction may persist.

Constriction, Pathologic↗