The effect of thyroid hormone treatment on the gene expression and enzyme activity of rat liver sodium-potassium dependent adenosine triphosphatase

The effects of thyroid hormone (T3) treatment on liver Na,K-adenosine triphosphatase (Na,K-ATPase) at the levels of subunit messenger RNA (mRNA), enzymatic activity, and enzyme content were studied in euthyroid rats injected for 5 consecutive days with T3. Northern and slot blot analyses of polyadenylated mRNA revealed that T3 treatment coordinately increases the level of mRNA encoding the alpha 1- and beta 1-subunits, approximately 4- and 3-fold, respectively, above basal levels. To determine whether this increase in the subunit mRNA consequently results in an increase in the synthesis of the enzyme, a modified liver cell fractionation procedure was developed, and the subcellular fractions from control and T3-treated livers were examined biochemically. Western blot analysis and Na,K-ATPase assay demonstrated that T3 treatment resulted in a 2-fold increase in both the amount and activity of the enzyme. Furthermore, the Western blot analysis of endoglycosidase-H-treated membrane fractions revealed an increase in the amount of the precursor beta-subunit in the T3-treated liver rough microsomal fraction, suggesting that an increase in subunit synthesis contributes at least partially to the increase in the rat liver Na,K-ATPase by T3 treatment.

Identification of a non-fluorescent isodicentric Y chromosome by molecular cytogenetic techniques

A 12 1/2-month-old girl was referred because of short stature, short neck, large internipple distance and simian crease on her right hand. By routine cytogenetic techniques the presence of an unidentifiable marker chromosome and loss of one X chromosome was noted (i.e. 45, X/46, X, mar/47, X, mar, +mar). By fluorescence in situ hybridization (FISH) technique, the marker chromosome was identified as an isodicentric non-fluorescent Y chromosome ((45, X/46, X, idic (Ynf)/47, X, idic (Ynf), +idic (Ynf)). Although the clinical significance of this finding cannot be assessed at present, possible development of gonadoblastoma in such cases is a major concern and warrants follow-up evaluations.

Management of medically fragile infants and children

Medically fragile infants and children present a host of challenges. The neonatal intensive care unit (NICU) is initially the mainstay of care for these infants, but it does not meet the critical developmental interactive needs of the child and parents to ensure positive psychosocial bonding. The care of these infants is further complicated by high daily costs (ranging from $1,000 to $2,500 per neonatal intensive care bed day) and lengthy, expensive inpatient stays (typically ranging from one week to five months or more). FHP Utah, a managed care organization, met these challenges through an innovative case management-oriented home care program called "Welcome Home." The program has produced a major impact on the quality and the cost of care for medically fragile infants. This article summarizes the first year's experience in implementing and operating the program.

Late-onset muscular weakness in phosphofructokinase deficiency due to exon 5/intron 5 junction point mutation: a unique disorder or the natural course of this glycolytic disorder?

Late-onset muscle weakness is rare in glycolytic disorders. There are two reports in the literature of phosphofructokinase (PFK)-deficient Ashkenazi Jews with severe vacuolar myopathy manifesting in late adulthood. The genetic abnormality in these patients is unknown. We report a third patient with a similar syndrome: early-onset exercise intolerance in young childhood and progressive weakness in a limb-girdle distribution appearing at 57 years of age, leading to severe incapacity. Muscle histology showed diffuse vacuolar changes, and muscle fibers contained excess glycogen-like material. Muscle biochemistry was diagnostic for PFK deficiency. DNA analysis from the patient and his family showed that he was homozygous for a recently identified point mutation at the exon 5/intron 5 junction (a G-to-A change); two other family members were heterozygous for this mutation. It is not clear whether late-onset weakness is the natural course for all PFK-deficient patients or whether the exon 5 mutation carries increased risk for this severe myopathy.

Home surgical recovery program proves value

The evidence is overwhelming that sharp reductions in health care costs can be achieved by reducing or eliminating reliance on expensive hospital care. In surgery, this is not always possible. However, significant savings can be achieved through reducing the length of time that a surgery patient must spend in the hospital. In outpatient surgery, the hospital stay is reduced to a single day. In this article, the authors describe a home surgical recovery program that has had great success in reducing hospital stays for even more complicated surgical procedures, frequently matching the achievements of outpatient surgery programs.

Homozygous deletions within chromosomal bands 9p21-22 in bladder cancer

The loss of DNA sequences on chromosomal bands 9p21-22 has been documented in a variety of malignancies including leukemias, gliomas, lung cancers, and melanomas. Because of the high incidence of monosomy 9 detected by both cytogenetics and loss of heterozygosity studies in bladder cancer, we examined seven bladder cancer cell lines for deletions in this region. Using seven DNA probes that span the region of 9p21-22 as well as a functional assay for methylthioadenosine phosphorylase (MTAP), which maps to 9p21, we found four cell lines that had small homozygous deletions. These deletions map centromeric to the interferon (IFN) gene cluster and telomeric to D9S171. Only one of the cell lines with deletions had a cytogenetically evident lesion in this chromosomal region. Preliminary loss of heterozygosity studies with 10 primary bladder cancer specimens using 10 markers spanning chromosome 9 revealed loss of heterozygosity at the IFN locus with retention of heterozygosity with more centromeric 9p markers and all informative 9q markers in the tumor of one patient. These data suggest that loss of a tumor suppressor gene on 9p21-22, which may represent a general pathway of oncogenesis, is important in bladder cancer development.

Retinal periphlebitis in multiple sclerosis

BACKGROUND

The ocular and visual manifestations of multiple sclerosis are varied. The most uncommon is sheathing of the veins, periphlebitis.

METHODS

A 39-year-old white female presented with primary visual complaints of contrast problems on a computer terminal. The patient was lost to follow up for 4 years, however, upon return a clinical diagnosis of multiple sclerosis was confirmed. Six years after the initial presentation, ophthalmoscopic exam of both eyes revealed marked focal sheathing of the retinal veins in the periphery, and associated hemorrhages in the right eye.

RESULTS

During follow-up, the left eye became further involved developing hemorrhages and a retinal hole, which was treated. The visual consequence of the multiple sclerosis as a result of further exacerbations were bilateral centrocecal scotomas and midly reduced visual acuity.

CONCLUSIONS

Multiple sclerosis should be considered in the differential diagnosis of patients with retinal periphlebitis.

A scanning tunnelling microscopy study of the formation and chemical activation of step defects on the basal plane of pyrolytic graphite

Scanning tunnelling microscopy is used to monitor etching of the basal plane of highly orientated pyrolytic graphite by ozone, oxygen and nitric acid. These treatments are seen to produce numerous single and multilayer step defects. Subsequent modification of the graphite sheet edges flanking these cavities by cyanuric chloride, TiCl4 and other reagents is shown to activate the edges, thereby making them capable of covalently binding various molecules.

Ectopia lentis, chorioretinal dystrophy and myopia. A new autosomal recessive syndrome

Four of five siblings born of a consanguineous marriage demonstrated abnormalities of the lens (ectopia lentis and dense cataracts) and retina (generalized tapetoretinal dystrophy and total retinal detachment) associated with myopia. This association in an autosomal recessive pedigree has not been previously noted.

Homozygous loss of the interferon genes defines the critical region on 9p that is deleted in lung cancers

Cytogenetic analyses of non-small cell lung cancer have revealed deletions of the short arm of chromosome 9 with breakpoints at 9p11-pter in a significant proportion of tumors. Recent evidence suggests that homozygous loss of the interferon (IFN) and methylthioadenosine phosphorylase (MTAP) genes located on 9p and a tumor suppressor gene closely linked to them is associated with acute lymphoblastic leukemia and with gliomas. We have observed alterations of DNA sequences on 9p which include the IFN genes at a significant frequency in all types of human lung cancers (20 of 56 or 36%). The genetic alterations observed include homozygous or hemizygous deletions of the IFN genes as well as rearrangement of contiguous DNA sequences. In addition to these genomic alterations, 10 of 22 (45%) cell lines examined lacked MTAP enzyme activity. Overall, 24 of 56 (43%) lung cancer cell lines examined had hemizygous or homozygous loss of DNA sequences which include the IFN or MTAP genes. These findings suggest that the putative tumor suppressor gene at this locus contributes to the malignant process in lung cancers, as well as other types of human cancer.

A 5' splice junction mutation leading to exon deletion in an Ashkenazic Jewish family with phosphofructokinase deficiency (Tarui disease)

A deficiency of the muscle isoform of the enzyme, phosphofructokinase (PFK, EC 2.7.1.11), leads to an illness (glycogenosis, Type VII) characterized by myopathy and hemolysis. A patient with this disease and an affected sister were found to have a G to A substitution at the 5' donor site of intron 5 of the PFK-M gene. This mutation led to a splicing defect: a complete deletion of the preceding exon in the patient's mRNA. The patient, an affected sister, and related and unrelated family members, who were of Ashkenazic Jewish background, were screened for the mutation by denaturing gradient gel electrophoresis and by allele specific hybridization of genomic DNA. The affected sisters are homozygous for the mutation, and their children, who are unaffected, are heterozygous. The only previously characterized genetic defect in this disease, found in a Japanese patient, was a G to T mutation at the beginning of intron 15 with splicing to a cryptic site within exon 15 (1). Both mutations lead to inframe deletions, but of different parts of the protein. The differences between the two aberrant proteins may account for clinical differences between our patients and the Japanese patient.

Inadequate immunizations. Identification using clinic charts

Immunizations are cost-effective measures for assuring public health. However, recent outbreaks of measles, mumps, and pertussis underscore the inadequacy of current immunization programs. A model identifying those children who are likely to be inadequately immunized could focus the use of limited health funds. A retrospective examination of the medical charts of 101 children in a large inner-city clinic was undertaken to determine if specific factors were associated with inadequate immunization status. Fifty percent of the children were inadequately immunized by 18 months of age (no measles-mumps-rubella or fewer than three diphtheria-pertussis-tetanus vaccinations). Logistic regression analyses showed that older maternal age, no recurrent or chronic illnesses, and vaginal delivery were independently associated with inadequate immunization status. However, on many charts, information on maternal, social, and environmental variables was incomplete. The increasing use of structured medical charts will enhance data collection and the determination of an appropriate index. A prospective study of the variables identified, along with standardization of medical records and inclusion of social history data, is necessary to further investigate the utility of screening criteria for inadequate immunizations.

Prolonged survival of two anencephalic infants

Two infants with anencephaly survived for 7 and 10 months without the need for prolonged assisted mechanical ventilation. One infant prospectively fulfilled all four criteria of the Medical Task Force on Anencephaly, making diagnosis almost certain. Prolonged survival of anencephalic infants is important not only to provide adequate counseling, but also for its relevance to organ transplantation.

Interleukin 6 modulates c-sis gene expression in cultured human endothelial cells

Human vascular endothelial cells secrete platelet-derived growth factor (PDGF)-like polypeptides which may mediate some of the vascular effects in the inflammatory process. We have demonstrated that IL-6 caused a significant increase in the mRNA level of the c-sis gene (PDGF B chain) in cultured human endothelial cells. IL-1 alpha and IL-1 beta also increased c-sis mRNA transcripts after an extended incubation period and both cytokines acted synergistically with IL-6 in increasing c-sis expression. Tumor necrosis factor enhanced the accumulation of c-sis mRNA and interferon-gamma decreased its level. In the inflammatory process specific cytokines can modulate c-sis expression in human endothelial cells. Their subsequent production of PDGF-like polypeptides could stimulate cell migration and proliferation, and cause the release of vascular inflammatory mediators.

Expression of a Wilms tumor gene in porcine kidney during compensatory renal growth

Expression of the putative Wilms tumor gene (WT-1) was studied to investigate its role in renal growth. Compensatory renal growth was induced in 35-day-old Yorkshire-swine by unilateral nephrectomy. The contralateral kidney was removed 0.5 to 72 hours following the initial operation and analyzed for WT-1 gene expression by Northern analysis. Compensatory renal growth was detectable by wet weight measurements at 12 hours following contralateral nephrectomy. WT-1 gene expression was detectable in the contralateral kidney as early as 0.5 hours following unilateral nephrectomy. Expression of this gene was not detected in normal kidney from swine of this age group or from sham operated swine. In addition, we demonstrated the expression of this gene in newborn rat, pig and human kidneys, as well as human fetal kidney, indicating its role in nephrogenesis. These data suggest that expression of the WT-1 gene is involved in the regulatory mechanisms that control different types of renal growth.

Cognitive performance in relatives of patients with probable Alzheimer disease: an age at onset effect?

Cognitive performance of 32 siblings and children of patients with probable Alzheimer disease was assessed longitudinally over an interval averaging 4 years. Mean scores were within normal limits for age on all measures at both test times. However, relatives of patients with early-onset dementia (less than or equal to 67 years) were more likely to show a decline in performance from the first to second testing than relatives of patients with late-onset dementia. Additional follow-up will be needed to determine the reliability of performance trajectories and to assess whether mild cognitive changes are related to future dementia. However, findings suggest that it may be important to consider family history of dementia in studies of normal cognitive aging.

Familial intracranial hypertension: report of a case and review of the literature

A mother and daughter are presented who had intracranial hypertension 5 years apart. Possible contributing factors were the presence of obesity and occasional asthma in both. A review of the literature reveals three other families with intracranial hypertension occurring in successive generations (suggesting autosomal dominant transmission) and four families with intracranial hypertension occurring in siblings (suggesting autosomal recessive transmission). No reported cases of familial intracranial hypertension have revealed a contributing cause.

EEG and neuroimaging localization in partial epilepsy

We have studied cortical localization provided by surface and sphenoidal electroencephalograms (EEGs) and that of computed tomography (CT), magnetic resonance imaging (MR) and single photon emission tomography (SPECT) in 58 patients with partial epilepsy. Each patient had EEG, MR and SPECT during a hospitalization period of 1-2 weeks. CT scans were obtained either during the same period or had been performed in the preceding year. EEG evaluation consisted of 3-5 days of continuous monitoring including video-telemetry and ambulatory recording as well as conventional EEGs with special electrode placements. Additionally 33 of 58 patients (55%) who were potential surgical candidates had sphenoidal recordings. All patients had an abnormal EEG which showed evidence of epileptic hyperexcitability. EEG abnormality was localized in 43 patients (74%). Neuroimaging studies were focally abnormal in 38 patients (66%); 12 CT (21%), 29 MR (50%) and 24 SPECT (41%). Thirty four of 43 patients with localized EEG had at least 1 focally abnormal neuroimaging study (79%), whereas 4 of 15 (27%) patients with non-localized EEG did so. Twenty-eight of 29 patients with focal MR (97%), 11 of 12 patients with focal CT (92%) and 20 of 24 patients with focal SPECT (83%) had a concordant focal EEG. EEG and neuroimaging localization agreed in all 15 patients in whom both MR and SPECT disclosed a concordant focal abnormality. This study demonstrates a significant (P less than 0.005) correlation between surface/sphenoid EEG and neuroimaging localization in partial epilepsy.