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Biomedical subjects

A Shah

Publications and source records attributed to A Shah.

At least 199 records · Page 11Linked to original sources

The relationship between two scales measuring aggressive behaviour among elderly nursing home residents.

Data from a large 6-month prospective study of aggressive behaviour in 11 nursing homes for the elderly are used to examine the relationship between two aggression scales (SOAS and RAGE). There was a strong and significant correlation between the SOAS and RAGE scales for the total and the subscale scores. Both these scales appear useful in measuring aggressive behaviour in nursing homes for the elderly and the nursing home staff can be trained in completing them effectively.

Aged↗

Two types of alpha-factor receptor determinants for pheromone specificity in the mating-incompatible yeasts S. cerevisiae and S. kluyveri.

The specificity of mating-pheromone systems helps prevent mating between different species of yeast. The mechanism of specificity of G protein-coupled receptors in other organisms may be similar. To determine the structural basis of species discrimination between alpha-factor variants, small extracellular segments of the Saccharomyces cerevisiae alpha-factor receptor were substituted with residues from the Saccharomyces kluyveri alpha-factor receptor. Three substitutions altered specificity towards S. cerevisiae and S. kluyveri alpha-factor pheromone peptides. A substitution at residues 47-49 affected specificity for pheromone binding but not for pheromone activation of response. Substitution of residues 267-269 affected pheromone specificity for activation of cellular responses, but not for pheromone binding (under the assay conditions used). Substitution of residues 104-123 modestly affected both types of specificity. These results suggest two distinct types of receptor/ligand specificity (perhaps corresponding to ligand binding to G protein-coupled or uncoupled conformational states of the receptor) that evolved independently as S. cerevisiae and S. kluyveri diverged as species.

Binding Sites↗

Incidence of premature birth and neonatal respiratory disease in infants of HIV-positive mothers. The Pediatric Pulmonary and Cardiovascular Complications of Vertically Transmitted Human Immunodeficiency Virus Infection Study Group.

OBJECTIVE: We sought to determine the prematurity rate in infants of HIV-positive mothers and to characterize the incidence and severity of neonatal respiratory disease in this population. STUDY DESIGN: From 1990 to 1994, 600 live-born infants of HIV-infected mothers were enrolled prenatally (73%) or postnatally (27%) from five U.S. centers. Logistic regression was used to determine the association of HIV status in the infant with prematurity (< or = 37 weeks), low birth weight (< or = 2.5 kg), and very low birth weight (< or = 1.5 kg) rates. The incidence of respiratory distress syndrome (RDS), bronchopulmonary dysplasia, meconium aspiration syndrome, and neonatal pneumonia was compared with anticipated rates for gestational age and birth weight. RESULTS: Very high rates of prematurity (19%), low birth weight (18.3%), and very low birth weight (3.3%) were found in the infants of HIV-positive mothers; and HIV infection in the infant was associated with younger gestational age. The overall incidence of RDS was 3% (17/600), which coincided with the anticipated rate, after adjusting for prematurity and birth weight. Only five infants (all < or = 1.5 kg) had bronchopulmonary dysplasia, and none required assisted ventilation beyond 14 days. Three term infants had mild meconium aspiration syndrome, and there were no cases of documented neonatal pneumonia. CONCLUSION: Infants born to HIV-positive mothers exhibited high prematurity and low birth weight rates, and the odds of prematurity were higher in infants who were infected with HIV. Despite the high incidence of prematurity and perinatal risk of this population, incidence and severity of neonatal respiratory disease were not higher than would be expected from available neonatal data in populations not exposed to HIV.

Adult↗

Allergic bronchopulmonary aspergillosis: the spectrum of computed tomography appearances.

Although computed tomography (CT) of the thorax has been compared to plain chest radiography and bronchography for demonstration of central bronchiectasis (CB) in allergic bronchopulmonary aspergillosis (ABPA), the CT presentation of the disease is yet to be highlighted. With this in view, the CT appearances in 23 patients with ABPA were evaluated. The scans were assessed for bronchial, parenchymal and pleural abnormalities. Central bronchiectasis was identified in all patients, involving 114 (85%) of the 134 lobes and 210 (52%) of the 406 segments studied. Other bronchial abnormalities such as dilated and totally occluded bronchi (11 patients), air-fluid levels within dilated bronchi (five patients), bronchial wall thickening (10 patients) and parallel-line shadows (seven patients) were also observed. Parenchymal abnormalities, which had a predilection for upper lobes, included consolidation in 10 (43%) patients, collapse in four (17%) patients and parenchymal scarring in 19 (83%) patients. A total of six cavities were seen in three (13%) patients, and an emphysematous bullae was detected in one (4%) patient. The pleura was involved in 10 (43%) patients. Ipsilateral pleural effusion with collapse was observed in one patient, while in nine other patients, parenchymal, lesions extended up to the pleura. Concomitant allergic Aspergillus sinusitis (AAS) was also detected in three (13%) of the 23 patients. Computed tomography of the thorax in patients with ABPA provides a sensitive method for the assessment of bronchial, parenchymal and pleural abnormalities, and should constitute a part of the diagnostic work of the disease.

Adolescent↗

New aromatic inhibitors of EPSP synthase incorporating hydroxymalonates as novel 3-phosphate replacements.

A new, aromatic analogue of the EPSP synthase enzyme reaction intermediate 1 has been identified, which contains a 3-hydroxymalonate moiety in place of the usual 3-phosphate group. This simplified inhibitor was readily prepared in five steps from ethyl 3,4-dihydroxybenzoate. The resulting tetrahedral intermediate mimic 9 is an effective, competitive inhibitor versus S3P with an apparent Ki of 0.57 +/- 0.06 microM. This result demonstrates that 3-hydroxymalonates exhibit potencies comparable to aromatic inhibitors containing the previously identified 3-malonate ether replacements and can thus function as suitable 3-phosphate mimics in this system. These new compounds provide another example in which a simple benzene ring can be used effectively in place of the more complex shikimate ring in the design of EPSP synthase inhibitors. Furthermore, the greater potency of 9 versus the glycolate derivative 10 and the 5-deoxy-analog 11, again confirms the requirement for multiple anionic charges at the dihydroxybenzoate 5-position in order to attain effective inhibition of this enzyme.

3-Phosphoshikimate 1-Carboxyvinyltransferase↗

Sleep disturbances in clinically stable young asthmatic adults.

BACKGROUND: Although nocturnal asthma is a well documented clinical problem, the effect of asthma on sleep itself and morbidity caused thereby have not received adequate attention. It is now recognized that partial sleep deprivation has a considerable effect on human functions. OBJECTIVES: With this in view, we conducted a study to determine the occurrence and nature of sleep disturbances in a homogeneous group of patients with clinically stable bronchial asthma in their home environment. METHODS: Thirty young adult unmarried university students with clinically stable bronchial asthma attending the Institute's outpatient department were asked to respond to an asthma/sleep questionnaire and were requested to maintain a sleep diary for 1 week. A similar group of 30 unmarried healthy young university students also underwent an identical workup and functioned as controls. Ten subjects from each group maintained a peak expiratory flow rate (PEFR) diary. RESULTS: The questionnaire revealed that 28 (93%) of the 30 patients experienced sleep disturbances (average 2.7/subject) as compared to 10 (33%) subjects in the control group (average 0.4/subject). The sleep diary confirmed that 27 (90%) of the 30 patients had sleep disturbances (2.4/subject/wk) as compared with 8 (27%) subjects (0.3/subject/wk) in the control group. These differences were statistically significant. Daytime sleepiness and tiredness (63%) and difficulty in maintaining sleep (60%) along with early morning awakening (46%) were more frequently seen. The asthmatic patients also had a shorter duration of sleep (427 min) as compared with the controls (474 min). These findings were significantly different from the control group. CONCLUSIONS: Increased daytime sleepiness and tiredness was perhaps a reflection of the poor quality of sleep experienced by patients with clinically stable asthma. This consequently may lead to impaired daytime performance which can have a potentially serious effect for the patient and society.

Administration, Inhalation↗

The relationship between two scales measuring aggressive behavior among continuing-care psychogeriatric inpatients.

Aggressive behavior among the elderly is a neglected area of research. An 18-week prospective study of aggressive behavior on a continuing-care psychogeriatric ward provided data to examine the relationship between two aggression scales (SOAS and RAGE). There was a strong and significant correlation between the SOAS and RAGE scales for the total and the subscale scores. Both these scales appear useful in measuring aggressive behavior among continuing-care psychogeriatric inpatients. Also, the nursing staff can be trained to complete these scales effectively.

Aged↗

Identification of 45 kD antigen in immune complexes of patients of allergic bronchopulmonary aspergillosis.

A glycoprotein antigen with an apparent mw of 45 kD was observed to be predominant in the circulating immune complexes isolated from patients of allergic bronchopulmonary aspergillosis as well as in the immune complexes prepared in vitro. Further characterisation of 45 kD antigen with trypsin showed four immunologically active peptides with mw 43, 36, 33 and 16 kD. Carbohydrate characterization using various lectins (Maackia amurensis agglutinin, Sambucus nigra agglutinin, Peanut agglutinin, Galanthus nivalis agglutinin and Datura stramonium agglutinin) showed presence of both N-linked and O-linked sugar moieties such as mannose, glucose, galactose and N-acetyl glucosamine. Predominant presence of 45 kD antigen in immune complexes, recognition of 45 kD by monoclonal antibodies raised against glycoprotein rich fraction of A. fumigatus and presence of elastinolytic protease activity indicate that 45 kD antigen is probably a potent virulence factor and may be contributing to the pathogenesis of ABPA by its biological as well as immunological activities.

Adult↗

A regional evaluation of variation in low-severity hospital admissions.

OBJECTIVE: Determine patient and hospital-level variation in proportions of low-severity admissions. DESIGN: Retrospective cohort study. SETTING: Thirty hospitals in a large metropolitan region. PATIENTS: A total of 43,209 consecutive eligible patients discharged in 1991 through 1993 with congestive heart failure (n = 25,213) or pneumonia (n = 17,995). MEASUREMENTS AND MAIN RESULTS: Admission severity of illness was measured from validated multivariable models that estimated the risk of in-hospital death; models were based on clinical data abstracted from patients' medical records. Admissions were categorized as "low severity" if the predicted risk of death was less than 1%. Nearly 15% of patients (n = 6,382) were categorized as low-severity admissions. Compared with other patients, low-severity admissions were more likely (p < .001) to be nonwhite and to have Medicaid or be uninsured. Low-severity admissions had shorter median length of stay (4 vs 7 days; p < .001), but accounted for 10% of the total number of hospital days. For congestive heart failure, proportions of low-severity admissions across hospitals ranged from 10% to 25%; 12 hospitals had rates that were significantly different (p < .01) than the overall rate of 17%. For pneumonia, proportions ranged from 3% to 22%; 12 hospitals had rates different from the overall rate of 12%. Variation across hospitals remained after adjusting for patient sociodemographic factors. CONCLUSIONS: Rates of low-severity admissions for congestive heart failure and pneumonia varied across hospitals and were higher among nonwhite and poorly insured patients. Although the current study does not identify causes of this variability, possible explanations include differences in access to ambulatory services, decisions to admit patients for clinical indications unrelated to the risk of hospital mortality, and variability in admission practices of individual physicians and hospitals. The development of protocols for ambulatory management of low-severity patients and improvement of access to outpatient care would most likely decrease the utilization of more costly hospital services.

Adult↗

DNA vaccination as anti-human immunodeficiency virus immunotherapy in infected chimpanzees.

The role of the immune response in controlling human immunodeficiency virus type 1 (HIV-1) replication is controversial. Immunotherapeutic strategies that have the ability to broaden immune responses might play a role in slowing disease progression. DNA immunization was studied as immunotherapy in infected chimpanzees. Two HIV-1-infected chimpanzees were vaccinated with DNA plasmid vaccines, one with plasmid pCMN160, which expresses the envelope glycoprotein of HIV-1MN and rev, and the other with a control plasmid. The chimpanzee immunized with pCMN160 demonstrated enhanced humoral responses. Virus load was monitored. Virus load in the chimpanzee receiving pCMN160 decreased at week 20 and has remained at background levels. The control chimpanzee was subsequently vaccinated with pCMN160. After immunization, the antibody responses increased and, as in the first animal, the virus load decreased. These results indicate the potential of the immune response to have a direct impact on HIV-1 replication in chimpanzees.

Amino Acid Sequence↗

Screening for depression among acutely ill geriatric inpatients with a short Geriatric Depression Scale.

BACKGROUND: Depression is not uncommon among acutely ill geriatric inpatients. METHOD: The performances of shorter versions of the Geriatric Depression Scale (GDS) in screening for depression among acutely ill geriatric inpatients were examined. RESULTS: A cut-off of 2/3 gives the best sensitivity (88%) and specificity (75%) for the 10-item version (GDS10). A cut-off of 0/1 gives the best sensitivity (72%) and specificity (90%) for the 4-item version (GDS4). A positive response to item 6 ("Do you often feel helpless?") on the GDS10 gave a sensitivity of 76% and specificity of 75%. Patients found the GDS10 tolerable and acceptable. CONCLUSION: Both shorter versions of the GDS may be utilized in screening for depression among acutely ill geriatric inpatients.

Aged↗

Mental disorders in children and adolescents with sickle cell disease.

This study compares the rate of mental disorders in children and adolescents with sickle cell disease with the rate in a corresponding control population. Using the clinical interview, a diagnosis based on DSM-III-R criteria for the presence of 13 mental disorders common to childhood was considered in a sequential sample of 39 subjects with sickle cell disease and a convenience sample of 26 same-race control subjects. Thirty-one percent of the sickle cell group and 42% of the control group screened positive for one or more of the selected mental disorders. The difference was not significant. When subgroups of mental disorders were considered (anxiety disorders, depressive disorders, disruptive behavior disorders, psychotic disorders, and other selected disorders), the differences were still not significant. This study suggests that children and adolescents with sickle cell disease do not have a greater risk for clinically significant mental disorders than same-race outpatient clinic controls. This study supports other reports in the medical literature that suggest that children attending outpatient medical clinics are at a higher risk for mental disorder than is seen in epidemiologic studies of nonmedical populations.

Adolescent↗

Lung surfactant proteins A and D can inhibit specific IgE binding to the allergens of Aspergillus fumigatus and block allergen-induced histamine release from human basophils.

Aspergillus fumigatus is an opportunistic fungal pathogen which, in the immunocompetent host, causes allergic disorders such as allergic rhinitis, allergic sinusitis, hypersensitivity pneumonitis, and allergic bronchopulmonary Aspergillosis (ABPA). In the present study, the interaction of 3-week culture filtrate (3wcf) allergens and various purified glycosylated and non-glycosylated allergens of A. fumigatus with lung surfactant proteins, SP-A and SP-D, was investigated. Purified SP-A and SP-D, isolated from human bronchoalveolar lavage fluid, bound to the 3wcf allergens and purified allergens, gp55 and gp45, in a carbohydrate-specific and calcium-dependent manner. Both SP-A and SP-D did not bind to deglycosylated allergens, suggesting that the ability of SP-A and SP-D to bind certain allergens is mediated through their carbohydrate recognition domains, interacting with the carbohydrate residues on the allergen. Both SP-A and SP-D could inhibit the ability of allergen-specific IgE from Aspergillosis patients to bind these allergens, suggesting that SP-A and SP-D may be involved in the modulation of allergic sensitization and/or development of allergic reactions. The view that SP-A and SP-D play a protective role against airborne allergens is further supported by the demonstration of their ability to inhibit A. fumigatus allergen-induced histamine release from allergic patients' basophils.

Allergens↗

Bile duct imaging and injury: a regional audit of laparoscopic cholecystectomy.

BACKGROUND: The aim of the present study was to report details of practice with respect to bile duct imaging and bile duct injury. METHODS: A prospective audit of laparoscopic cholecystectomy (LC) was undertaken in the Otago region from the introduction of LC in 1991 through to December 1995. The audit includes all procedures done by all surgeons in public and private hospitals over the period without exclusion. RESULTS: Laparoscopic cholecystectomy was attempted in 929 patients and completed laparoscopically in 832 (89.6%). Intraoperative cholangiography (IOC) was undertaken with increasing frequency over the study period, from 5.9% in 1991 to 32.2% in 1995. The overall IOC rate for individual surgeons varied from 4.5 to 47.6%. The use of peri-operative endoscopic retrograde cholangiopancreatography (ERCP) increased with the introduction of LC but has plateaued at approximately 6%. A total of 15.4% of patients with one or more clinical indicators of choledocholithiasis underwent LC without any form of bile duct imaging. Eight main bile duct injuries (0.86%) and a further 18 bile leaks occurred (total bile duct injury rate 2.8%). Intra-operative cholangiography was attempted (unsuccessfully) in only one patient with main duct injury, although five of the eight injuries were recognized intra-operatively. CONCLUSION: This prospective regional audit demonstrates a gradual return to the use of IOC, a modest but stable reliance on peri-operative ERCP, and a higher than expected rate of bile-duct injury.

Bile Ducts↗

Menstrual-linked asthma.

This study was conducted to determine the occurrence of menstrual-linked asthma (MLA) in India in 100 consecutive female asthmatics in the reproductive age group. The patients were required to respond to a questionnaire concerning the relationship between their asthma and the menstrual cycle. Twenty-three patients had subjective perception of deterioration in symptoms of asthma in relation to the menstrual cycle. Ten patients from both groups were also required to maintain a daily peak expiratory flow rate (PEFR) diary for 2 consecutive menstrual cycles. The mean total duration of illness in patients with MLA was significantly longer than in patients without cyclic exacerbation. Cough and breathlessness were also significantly more severe as was the disease. This was evidenced by the more frequent emergency room visits and hospitalizations in these patients. Menstrual-linked worsening of asthma was most common in the premenstrual week (17 patients), in 8 of these 17 patients, this phenomenon continued to occur during the menstrual week also. Interestingly, 1 patient complained of deterioration of asthma 2 days after menstruation was over. Such an observation is yet to be recorded. Fourteen patients reported an increase in symptoms with almost every cycle while 3 had worsening related to specific season only. Sixteen patients often required extra medication during the premenstrual and/or menstrual weeks. A significant association was also observed between severity of premenstrual syndrome and MLA. The mean PEFR values over 2 cycles revealed a significant fall in the morning as well as evening values in the premenstrual and menstrual weeks as compared to the midcycle week in patients with MLA. This fall was maximal in the premenstrual week. Such a fall was not observed in asthmatics without menstrual exacerbation of symptoms. MLA was detected in about a fourth of the female asthmatics in India and it appears to represent a more severe form of the disease. This study also documented that MLA was associated with an increase in airway resistance and was not simply due to an increased perception of symptoms during the premenstrual or menstrual weeks.

Adolescent↗

Telomerase activity in normal and neoplastic breast.

Telomerase activity is detected in the majority of human tumors and provides a mechanism to escape from proliferative limitations due to telomere loss. Similar to other studies, telomerase activity was detected with a modified telomeric repeat amplification protocol in the majority (76%) of 49 human breast cancer specimens, including most (75%) ductal carcinoma in situ specimens. There were no correlations between telomerase activity and tumor stage or estrogen/progesterone receptor status. In four of seven invasive tumors, telomerase expression seemed to be heterogeneous because not all microdissected regions were telomerase positive. Low levels of telomerase activity were also detected in a minority (17%) of breast specimens from patients without evidence of cancer. These findings suggest that telomerase activation can occur early in breast cancer progression and may be periodically down-regulated during subsequent progression.

Biomarkers, Tumor↗