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Biomedical subjects

A Zafar

Publications and source records attributed to A Zafar.

At least 19 recordsLinked to original sources
PubMed2004

Reducing ventilator-associated pneumonia rates through a staff education programme.

Ventilator-associated pneumonia (VAP) is the most common nosocomial infection in patients on mechanical ventilation and results in increases in mortality, prolonged hospitalization and costs. Preventive measures for VAP are well-documented and evidence-based, yet remain poorly implemented in most intensive care units. We undertook an observational pre and post-intervention study to assess whether an educational programme focusing on preventive practices for VAP could reduce the incidence. Six hundred and seventy-seven adult patients, mechanically ventilated for >48 h were included in the study population. An evidence-based guideline for preventive practices at the bedside was developed and disseminated to the intensive care unit staff. VAP incidence rates before and after implementation of the educational programme were compared. VAP infection rates reduced by 51%, from a mean of 13.2+/-1.2 in the pre-intervention period to 6.5+/-1.5/1000 device days in the post-intervention period (mean difference 6.7; 95% CI: 2.9-10.4, P =0.02). A multidisciplinary educational programme geared towards intensive care unit staff can successfully reduce the incidence rates of VAP. Further studies will be needed to assess the impact on broader outcome measures such as costs or mortality.

Adult↗
PubMed2004

Improved outcome after intestinal transplantation at a single institution over 12 years.

PURPOSE: To evaluate the outcomes of patients undergoing intestinal transplantation (IT). METHODS: Retrospective review was undertaken using existing medical records and database. RESULTS: Between November 1991 and May 2003, 114 patients were referred for consideration for IT, of which 33 patients received 37 intestinal allografts. All patients had intestinal failure and all patients had significant complications from total parenteral nutrition (TPN). TPN was the predominant cause of liver failure (63%). Combined liver intestinal grafts were used in the majority of patients. Overall 1- and 3-year patient survival is 77% and 52% with patients transplanted since 1999 having a 1- and 3-year survival of 94% and 73%, respectively. The most common cause of death was sepsis. No graft or patient was lost to cytomegalovirus or Epstein-Barr virus disease. Twenty-seven percent of allografts were lost to rejection. Long-term TPN independence is 82% for grafts more than 30 days after IT. Statistical analysis revealed several important factors impacting outcome. CONCLUSIONS: Successful IT defined as prolonged patient and graft survival and TPN independence can be readily achieved in select patients with IF and complications related to TPN therapy. Outcomes have improved with experience gained and control of viral infections and rejection.

Adolescent↗
PubMed2004

Induction therapy with interleukin-2 receptor antagonist after intestinal transplantation is associated with reduced acute cellular rejection and improved renal function.

PURPOSE: To determine the effectiveness of induction immunotherapy with interleukin-2 receptor antagonists (IL2RA) after intestinal transplantation (IT). METHODS: A single-center, retrospective study was undertaken of all patients undergoing IT using existing medical records and database. Immunotherapy was either triple (standard maintenance triple therapy [SMTT]) or IL2RA [induction IL2RA plus SMTTx] or OKT3 [induction antilymphocyte preparations plus SMTTx]). Data was collected for the first 175 postoperative days. Outcomes included pretransplant renal function, posttransplant serum creatinine normalized to age (nl-sCR), rejection (ACR), and survival. Standard statistical analysis was undertaken. RESULTS: There were no significant differences in the groups: triple (n = 10, median age 3.5 years, cGFR 106 +/- 44 mL/min), IL2RA (n = 13, median age 3.2 years, cGFR 101 +/- 61 mL/min), OKT3 (n = 4, median age 7.7 years, cGFR 104 +/- 27 mL/min). nl-sCR was significantly (P <.01) lower in IL2RA at most postoperative weeks. IL2RA had significantly fewer rejection and infectious episodes than the other two groups. Three-year patient survival was 92% in IL2RA versus 50% triple and OKT3. CONCLUSIONS: IL2RA immunotherapy after IT is associated with a lower incidence of renal dysfunction as compared with historical controls. Furthermore, IL2RA therapy resulted in a lower incidence of rejection and improved survival. IL2RA should be considered in select patients undergoing IT.

Child↗
PubMed2004

Evaluation of frequency of isolation and trends in antibiotic resistance among Campylobacter isolates over 11 year period.

OBJECTIVE: To analyze frequency of isolation and trends in antibiotic resistance among Campylobacter isolates over 11 year period in Microbiology Laboratory, Aga Khan University from the year 1992-2002. METHODS: Total 52,777 stool specimens were processed during the study period. Enteric pathogens isolated from 8,483 stool samples were further analyzed for frequency of isolation and antimicrobial resistance. Statistical Analysis was done by using descriptive statistics of SPSS version 10. Values were expressed as percentages, mean and rates. RESULTS: Campylobacter species were third in frequency of isolation with an isolation rate of 24.8%. C. jejuni was the predominant pathogen followed by C.coli. Isolation rate of Campylobacter was higher (45.7%) among children under 2 years of age as compared to other age groups. A steady rise in resistance among Campylobacter isolates against ampicillin; tetracycline and ofloxacin has been noted whereas resistance against erythromycin remained fairly low. CONCLUSION: The isolation of Campylobacter is higher from stool specimens of children of less than two years of age rendering Campylobacteriosis to be an important cause of gastroenteritis in pediatric population. This study also demonstrates a steady rise in antibiotic resistance in Campylobacter isolates especially against quinolones with fall in resistance against erythromycin throughout the study period.

Adolescent↗
PubMed2003

Seasonal variation in bacterial pathogens isolated from stool samples in Karachi, Pakistan.

OBJECTIVE: To determine the seasonal variation of the commonly isolated bacterial pathogens in stool samples. MATERIAL AND METHODS: A retrospective descriptive study was undertaken of all the stool samples submitted from within Karachi to the Aga Khan University Hospital Laboratory over a period of five years (January 1997- December 2001) in order to determine the commonly isolated bacterial pathogens and to predict their seasonal variation. RESULTS: A total of 16379 stool samples were included in this review. Bacterial isolates were found in 6670 stool samples (culture detection rate=40.7%). The mean age at the time of culture of each sub-group was < or = 1 year group (6.58 +/- 3.1 months), 1-5 years (2.13 +/- 0.94 years), 5-14 years (8.3 +/- 2.6 yrs) and adults (43.2 +/- 18.5 years). Male: Female ratio was 1.2:1. Vibrio cholera 01 Ogawa (32.8%), Campylobacter jejuni (17.3%), Enteropathogenic Escherichia coli (9.9%), Salmonella paratyphi b (6.6%) and Shigella flexneri (6.2%) were the most common organisms isolated. These organisms show a distinct seasonal variation with summer predilection. CONCLUSION: In contrast to the previous studies from South Asia, which have identified E. coil, followed by Vibrio cholerae as the most common enteric isolates, we found Vibrio cholera 01 Ogawa followed by Campylobacter jejuni as the most common enteric pathogens isolated in an urban setting. It is important to consider seasonal variation when empirically treating diarrheal diseases in our region.

Adolescent↗
PubMed2003

Comparison of double disc and combined disc method for the detection of extended spectrum beta lactamases in enterobacteriaceae.

OBJECTIVE: To compare double disc approximation and combined disc method for their ability to detect extended spectrum b lactamase (ESBL) production in enterobacteriaceae and determine the percentage of isolates which are falsely reported as sensitive in absence of ESBL detection, in a clinical microbiology laboratory of a tertiary care hospital between September-October 2002. METHODS: Selected isolates were identified according to standard biochemical tests. Disc susceptibility tests were performed according to NCCLS. ESBL detection by combined disc [cefotaxime (30 ug) versus cefotaxime plus clavulanate (30+10 ug)] was compared with detection using double discs [amoxy-clavulanic acid (20+10 ug) and aztreonam (30 ug) applied 10 mm apart]. Results were interpreted according to NCCLS and analysed on SPSS version 10. RESULTS: ESBL production was detected in 140 (30%) isolates by combined disc method and 139 (29.5%) by double disc method. There was no significant difference between two methods. Of the ESBL positive isolates 41 (29%) gave zone diameters that were within the sensitivity range cutoff and would have been falsely reported as being beta lactam sensitive in absence of ESBL detection. CONCLUSION: ESBL detection should be routinely performed in clinical laboratories as false reporting would result in treatment failure despite in vitro sensitivity. No difference was found between the combined disc and double disc methods hence either of two could be used.

Enterobacteriaceae↗
PubMed2000

Synthesis and characterization of nickel(II) bis(alkylthio)salen complexes.

NiX2(2-RSC6H4CH=NCH2CH2N=CHC6H4SR-2) (NiX2L; L = 5) (1a, X = Br, R = C6H13; 1b, X = Cl, R = C12H25) and NiX2(2-C6H13SC6H4CH2NHCH2CH2NHCH2C6H4SC6H13-2) (NiX2L; L = 6) (2a, X = Br; 2b, X = Cl; 2c, X = OClO3) were prepared from ligands 5 and 6, respectively. The 1:2 metal-ligand complex Ni(OClO3)2(2-RSC6H4CH2NHCH2CH2NHCH2C6H4SR-2)2 3, was obtained from an EtOH solution of 2c. The characterization of paramagnetic 1-3 included single-crystal X-ray diffraction studies of 1a and 3. Complex 2c converted into 3 in the presence of excess ligand 6 in CHCl3.

Journal Article↗
PubMed2000

Cholesterol inhibits the nuclear entry of estrogen receptor activation factor (E-RAF) and its dimerization with the nonactivated estrogen receptor (naER) in goat uterus.

An alternative form of estrogen receptor isolated from goat uterus, the nonactivated estrogen receptor (naER), has no DNA-binding function, although it is closely similar to the classical estrogen receptor (ER) in its hormone binding affinity and specificity. The naER dimerizes with a DNA binding protein, estrogen receptor activation factor (E-RAF). The heterodimer binds to the DNA. Assays carried out during the purification of E-RAF showed that an endogenous inhibitor that is heat stable and dialyzable bound to the E-RAF and prevented the formation of the heterodimer. The inhibitor has been isolated and purified. GC-MS analysis identifies this molecule to be cholesterol. Circular dichroism measurement has shown that the high-affinity binding of cholesterol to E-RAF results in subtle changes in the secondary and the tertiary structure of the protein. The E-RAF with altered conformation fails to dimerize with the naER. Instead of facilitating E-RAF entry into the nucleus, dimerization with the naER prevents it. Similarly, cholesterol binding blocks the nuclear entry of the protein, showing that E-RAF with altered conformation is incapable of interaction with the nuclear pore complex/membrane proteins. The naER-E-RAF heterodimer remains at the nuclear periphery, incapable of further transport. These results indicate the possibility that the dimerization between naER and the E-RAF takes place only within the nuclear compartment. The observation that cholesterol binding prevents nuclear entry of the E-RAF reflects the similarity of E-RAF with the sterol regulatory element (SRE) binding protein that enters the nucleus and binds to SRE only when the intracellular level of cholesterol remains low.

Animals↗
PubMed2000

In-vitro antimicrobial activity of Cefpirome: a new fourth-generation cephalosporin against clinically significant bacteria.

OBJECTIVE: To study the in-vitro antimicrobial activity of Cefpirome: A new fourth generation Cephalosporin in comparison with other agents against clinically significant Gram-negative and Gram-positive bacteria. SETTING: A multi-center in-vitro study was conducted in 13 centers. MATERIALS AND METHODS: Bacterial isolates--A total of 1300 isolates were collected from different clinical laboratories and hospitals at 13 centers. Organisms were identified by the API identification systems (API systems, SA Vericeu, France). The age and sex of each patient, type of hospital unit, source of the isolate and genus and species of the bacteria were recorded on standardized report forms. The sensitivity testing was carried out by the "NCCLS (modified Kirby-Bauer) method"--using Mueller-Hinton agar. RESULTS: The results suggest that Cefpirome has a potential clinical advantage against gram-positive and gram-negative bacteria resistant to other third generation cephalosporins. CONCLUSION: Cefpirome was active against both gram-negative and gram-positive organisms. Cefpirome was more active than ceftazidime, cefoperazone, ceftizoxime and ceftriaxone against E. coli, Klebsiella spp, Enterobacter spp, Proteus spp, Salmonella typhi, Enterococci, methicillin sensitive Staphylococci and Betahemolytic Streptococci. The activity of Cefpirome was comparable with ceftazidime against pseudomonas aeruginosa. Cefpirome had the smallest numbers of resistant isolates. Cefpirome was more active than other third generation cephalosporins compared in this study against E. coli (87% vs 61%), Klebsiella spp (84% vs 56%), Enterobacter spp (88% vs 59%), Proteus spp (97% vs 92%), Salmonella typhi (98% vs 96%), methicillin sensitive Staphylococci (86% vs 59%) and Enterococci spp (82% vs 72%).

Bacteria↗
PubMed1999

The temporal order judgment paradigm: subcortical attentional contribution under exogenous and endogenous cueing conditions.

The role of subcortical attentional processing was investigated under exogenous and endogenous cueing conditions. As retinotectal projections arise predominantly from the nasal retina i.e., temporal hemifield, subcortical attention should be distributed asymmetrically under monocular viewing conditions with a temporal hemifield advantage. We compared the results of monocular and binocular viewing conditions using a temporal order judgment (TOJ) paradigm. Subjects fixated a centrally located cross and two stimuli were presented with a variable onset asynchrony. Three experiments were conducted: no cue, exogenous cue and endogenous cue. Subjects reported which stimulus seemed to appear first. An effect consistent with subcortical processing was found under exogenous cueing conditions. No such effect was found under endogenous cueing conditions. We believe that subcortical attentional processing in response to an exogenous cue facilitates rapid shifts in attention towards environmental stimuli. We found no evidence for subcortical processing in voluntary directed attention and believe this process to be cortical in nature.

Adolescent↗
PubMed1999

The Regenstrief Medical Record System: a quarter century experience.

Entrusted with the records for more than 1.5 million patients, the Regenstrief Medical Record System (RMRS) has evolved into a fast and comprehensive data repository used extensively at three hospitals on the Indiana University Medical Center campus and more than 30 Indianapolis clinics. The RMRS routinely captures laboratory results, narrative reports, orders, medications, radiology reports, registration information, nursing assessments, vital signs, EKGs and other clinical data. In this paper, we describe the RMRS data model, file structures and architecture, as well as recent necessary changes to these as we coordinate a collaborative effort among all major Indianapolis hospital systems, improving patient care by capturing city-wide laboratory and encounter data. We believe that our success represents persistent efforts to build interfaces directly to multiple independent instruments and other data collection systems, using medical standards such as HL7, LOINC, and DICOM. Inpatient and outpatient order entry systems, instruments for visit notes and on-line questionnaires that replace hardcopy forms, and intelligent use of coded data entry supplement the RMRS. Physicians happily enter orders, problems, allergies, visit notes, and discharge summaries into our locally developed Gopher order entry system, as we provide them with convenient output forms, choice lists, defaults, templates, reminders, drug interaction information, charge information, and on-line articles and textbooks. To prepare for the future, we have begun wrapping our system in Web browser technology, testing voice dictation and understanding, and employing wireless technology.

Computer Terminals↗
PubMed1999

Prevalent nosocomial gram negative aerobic bacilli and their antimicrobial susceptibility pattern in intensive care unit.

OBJECTIVE: To determine the type of prevalent aerobic gram-negative bacilli and their sensitivity pattern among nosocomial isolates. DESIGN: Prospective collection of clinically significant nosocomial gram negative bacilli. SETTING: Tertiary care hospital in Karachi. METHOD: One hundred isolates were identified by standard methods and minimum inhibitory concentration was checked by epsilometer test. RESULTS: The most frequent isolates were Eschericia coli (43%) followed by Klebsiella pneumoniae (18%) Acinetobacter spp. (7%) Enterobacter spp. (7%) and Klebsiella spp. other than pneumoniae (7%). Most of the isolates of dominant species (E. coli and Klebsiella pneumoniae) were multiresistant including third generation cephalosporins. CONCLUSION: This study indicates that most effective antibiotics imipenem and amikacin inhibited most of the isolates. Imipenem alone or amikacin in combination with one broad spectrum beta-lactam drug should be used in initial empiric therapy in any life threatening nosocomial infection.

Amikacin↗
PubMed1997

Fine needle aspiration cytology in parotid lumps.

Over a period of two years, Fine Needle Aspiration Cytology (FNAC) was performed on 33 patients presenting with a parotid lump. Five patients were excluded as they were treated medically after FNAC report. The FNAC results of 28 cases were compared with histopathological diagnoses of surgically resected specimens. There were 8 true positive, 17 true negative, 1 false positive and 2 false negative cases. Sensitivity was 80%, specificity 94.4% and diagnostic accuracy 89.3%. FNAC is a simple quick, accurate and virtually complications free investigative modality. It is also helpful adjunct to assess preoperatively the suitability and extent of the surgical treatment.

Adolescent↗
PubMed1997

Isolation and identification of Aeromonas species from human stools.

One thousand and three diarrhoeal stool samples were processed in our laboratory during the period 1996/1997 for the presence of enteric pathogens especially Aeromonas spp., which has emerged as a new agent causing diarrhoea. Ampicillin sheep blood agar was found to be the best medium for the isolation of Aeromonas spp. from stool specimens. Enteric pathogens were found in 200 (20%) stools, of which Aeromonas spp. was the second commonest pathogen isolated amounting to 21% of isolates. This study clearly indicates that Aeromonas spp. must be looked for in every diarrhoeal stool samples, specially in children below 10 years of age. Isolation and identification is cost effective and easy, if the given protocol is observed.

Aeromonas↗