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Biomedical subjects

R Rao

Publications and source records attributed to R Rao.

At least 73 records · Page 4Linked to original sources
PubMed1999

Neuropsychological impairment in stroke, carotid stenosis, and peripheral vascular disease, A comparison with healthy community residents.

BACKGROUND AND PURPOSE: An increasing body of literature suggests a role for clinically "silent" cerebrovascular disease in the pathogenesis of cognitive impairment. Such pathology commonly occurs in the absence of stroke. The main aim of the study was to examine neuropsychological impairment associated with cerebrovascular and peripheral vascular disease (PVD) and to compare cognitive deficits with a nonvascular control group. The main hypothesis was that older people with both transient ischemic attack (TIA) and PVD would demonstrate greater cognitive impairment than controls. METHODS: A battery of neuropsychological tests was administered to 4 groups of community residents older than 65 years. The groups comprised 25 patients with carotid stenosis and TIA, 25 nonamputees with PVD, 25 patients with stroke, and 25 matched (with the stroke group) controls. RESULTS: Stroke patients showed greater impairment than controls in all tests. PVD patients did not perform significantly worse (P<0.05 after Bonferroni correction) than control subjects on any of the neuropsychological tests. However, 25% of PVD patients had scores lying within the bottom 5% of control group scores for attention, calculation, and 1 test of frontal lobe function. TIA patients were more impaired in general intellectual impairment and frontal lobe function than controls. Frontal lobe impairment, suicidal thinking, and age were all independent predictors of global cognitive impairment in the TIA group. Frontal lobe impairment was the only predictor of global cognitive impairment in the PVD group. CONCLUSIONS: TIA and PVD patients showed similar patterns of neuropsychological impairment, but TIA may result in more prolonged cognitive impairment, particularly in frontal lobe function. This group may be at increased risk of vascular dementia as well as impulsivity and suicide.

Aged↗
PubMed1999

Obsessive-compulsive disorder symptoms before and after recovery from bulimia nervosa.

OBJECTIVE: Obsessive-compulsive disorder (OCD) symptoms are common in people who are ill with bulimia nervosa. However, little is known about whether OCD symptoms persist after long-term recovery from bulimia. METHOD: Thirty-one female patients with bulimia nervosa, 29 women who had been recovered from bulimia for more than 1 year, and 19 healthy female comparison subjects completed the Yale-Brown Obsessive Compulsive Scale, which measures OCD-like symptoms. Items related to symptoms of core eating disorders were omitted from the Yale-Brown scale. RESULTS: The Yale-Brown scale scores of the women with bulimia (mean = 13.1, SD = 10.6) and those who had recovered from bulimia (mean = 7.9, SD = 7.0) were significantly higher than the scores of the normal comparison subjects (mean = 1.9, SD = 2.6). Women with bulimia and those who had recovered from bulimia had similar Yale-Brown scale scores and endorsed similar Yale-Brown scale target symptoms, such as obsessions related to symmetry and exactness. CONCLUSIONS: OCD symptoms persist after recovery from bulimia. Moreover, the types of OCD symptoms experienced by bulimia patients do not vary dramatically with improvement in bulimic symptoms. Persistent OCD symptoms after recovery from bulimia raise the possibility that these behaviors are trait-related and contribute to the pathogenesis of bulimia.

Adult↗
PubMed1999

Systemic effects of inhaled corticosteroids on growth and bone turnover in childhood asthma: a comparison of fluticasone with beclomethasone.

Inhaled steroids are frequently used in childhood asthma, but concerns based on limited objective evidence remain, regarding long-term side-effects. In this study the systemic effects of standard doses of inhaled steroids in childhood asthma were assessed, comparing beclomethasone dipropionate (BDP) with fluticasone propionate (FP). The study was prospective, randomized and double-blind. Twenty-three steroid-naive children with moderately severe asthma, aged 5-10 yrs, were allocated either BDP (400 microg x day(-1) or FP (200 microg x day(-1)) using a metered-dose inhaler with a spacer. Asthma control was assessed at regular intervals over 20 months. Fasting morning blood and overnight urine samples were collected for estimation of serum cortisol, serum 1-carboxyterminal telopeptide (ICTP), serum osteocalcin and urine deoxypyridinoline (DPD). Bone mineral density (BMD) was measured at each visit. None of the markers of bone turnover showed any change during the study period. BMD increased at normal rates with age. Serum cortisol significantly decreased on BDP, but not on FP. A significant difference in growth rates was found between the groups, with a slower rate of growth towards the end of the observation period in the BDP group. In conclusion when taken in a relatively modest dose over a period of time, beclomethasone dipropionate had significant effects on the hypothalamic-pituitary-adrenal axis and statural growth in childhood asthma. These systemic effects were not seen with an equipotent dose of fluticasone propionate.

Administration, Inhalation↗
PubMed1999

Ocular torticollis and facial asymmetry.

OBJECTIVE: Ocular torticollis secondary to congenital superior oblique palsy can be associated with facial asymmetry. The purpose of this study was to determine if other ocular causes of head tilting also carry the same association. DESIGN: The study design was clinical evaluation of patients. PARTICIPANTS: Fifteen patients with marked, moderate, or mild head tilts associated with dissociated vertical deviation (DVD), and 3 patients with nystagmus and a torsional null point. A control group was comprised of 3 patients with congenital superior oblique palsy, 3 with traumatic superior oblique palsy, and two normal patients. INTERVENTION: A masked observer analyzed full-face photographs of the subjects. MAIN OUTCOME MEASURE: The presence of facial asymmetry. RESULTS: Facial asymmetry due to bending in/of the sagittal plane of at least two degrees was found in 3 of 4 patients with a marked head tilt from DVD, in 2 of 5 five patients with a moderate head tilt from DVD, in one of 3 patients with a head tilt due to nystagmus, and in one of 3 patients with a head tilt due to congenital superior oblique palsy. None of the patients with a mild head tilt from DVD, traumatic superior oblique palsy, or the normal controls had clinically noticeable facial asymmetry. CONCLUSION: Facial asymmetry can be associated with abnormal head postures, specifically, large head tilts from DVD or nystagmus.

Facial Asymmetry↗
PubMed1999

Primitive reflexes in cerebrovascular disease: a community study of older people with stroke and carotid stenosis.

OBJECTIVES: To determine the prevalence of primitive reflexes (frontal release signs) in elderly community residents with cerebrovascular disease and to examine their relationship with neuropsychological and mood-related variables. METHODS: Three groups of 25 people over 65 with anterior circulation stroke, transient ischaemic attack (TIA) and a control group were assessed using measures of generalized cognitive impairment, frontal lobe dysfunction, frontal release signs and mood-related variables. Predictors of cerebrovascular disease were examined further in stroke and TIA groups. RESULTS: Both stroke and TIA groups showed a higher mean score on the Frontal Release Signs Scale and a higher prevalence of most reflexes than the control group. Verbal fluency and DSM-IV depressive disorder were independent predictors of frontal release signs. CONCLUSION: TIAs may predispose to subtle neurological impairment, which may be mediated by frontal lobe damage. Their role in the pathogenesis of depression in later life requires further exploration.

Affect↗
PubMed1999

Clinicopathological correlation of diaphragmatic contraction band necrosis in a neonatal and infantile population--an autopsy study.

Contraction band necrosis' is a lesion widely studied in myocardial fibres (Heart) and to some extent in skeletal and smooth muscles. The phenomenon of Diaphragmatic Contraction Band necrosis (D-CBN) occurring in the diaphragms of 53 neonates and infants removed at autopsy were studied microscopically. Of these D-CBN was present in 19 (35.85%) cases. D-CBN presented in two morphological patterns (I) solid ('Block-like') segmental necrosis in 31.58% cases or (ii) Ribbon-like transfiber (shredded appearance) bands in 15.79% cases. A combination of both the above lesions were observed in a vast majority of cases, i.e. 52.63% cases. A clinicopathological correlation was attempted as regards cause and mode of death with occurrence and severity of D-CBN. It was found that severe D-CBN was present in the group of birth asphyxia (26.92%) and infant infections (20.0%). The presence and frequency of D-CBN in autopsied subjects proved useful in interpreting the cause and mode of death.

Autopsy↗
PubMed1998

Novel localization of a Na+/H+ exchanger in a late endosomal compartment of yeast. Implications for vacuole biogenesis.

Na+/H+ exchangers catalyze the electrically silent countertransport of Na+ and H+, controlling the transmembrane movement of salt, water, and acid-base equivalents, and are therefore critical for Na+ tolerance, cell volume control, and pH regulation. In contrast to numerous well studied plasma membrane isoforms (NHE1-4), much less is known about intracellular Na+/H+ exchangers, and thus far no vertebrate isoform has been shown to have an exclusively endosomal distribution. In this context, we show that the yeast NHE homologue, Nhx1 (Nass, R., Cunningham, K. W., and Rao, R. (1997) J. Biol. Chem. 272, 26145-26152), localizes uniquely to prevacuolar compartments, equivalent to late endosomes of animal cells. In living yeast, we show that these compartments closely abut the vacuolar membrane in a striking bipolar distribution, suggesting that vacuole biogenesis occurs at distinct sites. Nhx1 is the founding member of a newly emergent cluster of exchanger homologues, from yeasts, worms, and humans that may share a common intracellular localization. By compartmentalizing Na+, intracellular exchangers play an important role in halotolerance; furthermore, we hypothesize that salt and water movement into vesicles may regulate vesicle volume and pH and thus contribute to vacuole biogenesis.

Amino Acid Sequence↗
PubMed1998

Substitutions of aspartate 378 in the phosphorylation domain of the yeast PMA1 H+-ATPase disrupt protein folding and biogenesis.

There is strong evidence that Asp-378 of the yeast PMA1 ATPase plays an essential role in ATP hydrolysis by forming a covalent beta-aspartyl phosphate reaction intermediate. In this study, Asp-378 was replaced by Asn, Ser, and Glu, and the mutant ATPases were expressed in a temperature-sensitive secretion-deficient strain (sec6-4) that allowed their properties to be examined. Although all three mutant proteins were produced at nearly normal levels and remained stable for at least 2 h at 37 degrees C, they failed to travel to the vesicles that serve as immediate precursors of the plasma membrane; instead, they became arrested at an earlier step of the secretory pathway. A closer look at the mutant proteins revealed that they were firmly inserted into the bilayer and were not released by washing with high salt, urea, or sodium carbonate (pH 11), treatments commonly used to strip nonintegral proteins from membranes. However, all three mutant ATPases were extremely sensitive to digestion by trypsin, pointing to a marked abnormality in protein folding. Furthermore, in contrast to the wild-type enzyme, the mutant ATPases could not be protected against trypsinolysis by ligands such as MgATP, MgADP, or inorganic orthovanadate. Thus, Asp-378 functions in an unexpectedly complex way during the acquisition of a mature structure by the yeast PMA1 ATPase.

Amino Acid Substitution↗
PubMed1998

A controlled family study of anorexia nervosa and bulimia nervosa: psychiatric disorders in first-degree relatives and effects of proband comorbidity.

BACKGROUND: We used contemporary family-epidemiological methods to examine patterns of comorbidity and familial aggregation of psychiatric disorders for anorexia and bulimia nervosa. METHODS: Direct interviews and blind best-estimate diagnostic procedures were used with diagnostically "pure" groups of probands with eating disorders and a matched control group. Lifetime prevalence rates of eating disorders, mood disorders, substance use disorders, anxiety disorders, and selected personality disorders were determined in female probands with restricting anorexia nervosa (n=26) or bulimia nervosa (n=47), control women (n=44), and first-degree biological relatives (n=460). RESULTS: Relatives of anorexic and bulimic probands had increased risk of clinically subthreshold forms of an eating disorder, major depressive disorder, and obsessive-compulsive disorder. Familial aggregation of major depressive disorder and obsessive-compulsive disorder was independent of that of anorexia nervosa and bulimia nervosa. These relatives also had increased risk of other anxiety disorders, but the mode of familial transmission was not clear-cut. The risk of substance dependence was elevated among relatives of bulimic probands compared with relatives of anorexic probands, and familial aggregation was independent of that of bulimia nervosa. The risk of obsessive-compulsive personality disorder was elevated only among relatives of anorexic probands, and there was evidence that these 2 disorders may have shared familial risk factors. CONCLUSIONS: There may be a common familial vulnerability for anorexia nervosa and bulimia nervosa. Major depressive disorder, obsessive-compulsive disorder, and substance dependence are not likely to share a common cause with eating disorders. However, obsessional personality traits may be a specific familial risk factor for anorexia nervosa.

Adolescent↗
PubMed1998

Vascular dementia: dead or alive?

The term 'Vascular Dementia' remains popular as a diagnostic entity, since it encompasses a variety of vascular pathologies. This is in stark contrast to many clinical classificatory systems that weight their definitions strongly towards stroke alone. A diagnosis of vascular dementia is complicated by compounding factors that reduce both the validity and specificity of diagnostic systems. This review highlights some of the problems faced in epidemiological, clinical, neuropathological and radiological studies attempting to define a clear-cut syndrome of dementia associated with cerebrovascular disease. The role of non-stroke ischaemia is also discussed. It is concluded that the term vascular dementia may have outlived its usefulness as a valid concept; alternative approaches are suggested.

Cerebrovascular Disorders↗
PubMed1998

Effect of inhaled corticosteroids on bone mineral density in childhood asthma: comparison of fluticasone propionate with beclomethasone dipropionate.

There is a dearth of data on long-term effects of inhaled corticosteroids (ICS) on bone architecture in childhood asthma. This study was designed to assess the possible effects of two different inhaled steroids on bone mineral density (BMD) in steroid-naïve, prepubertal children. Twenty-three children were randomized to receive equipotent doses of either fluticasone propionate (100 micrograms twice daily) or beclomethasone dipropionate (200 micrograms twice daily). They were followed up over a period of 20 months with regular dual-energy X-ray absorptiometry scans for BMD. Densitometry of lumbar spine and total body showed a significant increase over time, which followed the normal patterns for growth. No difference was observed between the two subgroups. There was no change in fat distribution over time and no increase in percentage total body fat. As expected, girls had significantly higher total body fat. This absence of deleterious effects suggests that in the standard doses used neither beclomethasone nor fluticasone has any significant effect on bone density over a moderate period of time. Further studies should continue monitoring BMD through the critical years of bone mass accumulation during adolescence.

Absorptiometry, Photon↗
PubMed1998

Reproducibility of 1H-NMR integrals: a collaborative study.

The quantitative use of NMR spectroscopy was investigated by a reproducibility study of 1H-NMR integrals involving five laboratories. A significant laboratory effect was found confirming the difficulty to obtain very precise data by integration of complex signals. The reproducibility of any NMR assay measurement, which requires a high precision should be validated by an interlaboratory study.

Evaluation Studies as Topic↗
PubMed1998

Conversion of hemiarthroplasty to total hip arthroplasty: can groin pain be eliminated?

In this study 45 patients with groin or buttock pain after hemiarthroplasty were evaluated 2 to 7 years after conversion to total hip arthroplasty. Groin or buttock pain was completely relieved in 36 patients (80%) and partially relieved in an additional 4 patients (9%). After conversion surgery, 9 patients continued to have groin or buttock pain, but no factor could be identified that would predict an unsuccessful result. The hypothesis tested in this study was whether conversion of a hemiarthroplasty to a total hip arthroplasty eliminates groin pain. Because a significant number of patients (up to 20%) will continue to have some groin or buttock pain after conversion surgery, patients should be warned of this contingency before surgery.

Acetabulum↗