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A Ali

Publications and source records attributed to A Ali.

At least 19 recordsLinked to original sources
PubMed2026

Genomic characterisation and lytic potential of phage SF01 against multidrug-resistant Salmonella enterica subsp. enterica, a key agent of infection in poultry.

1. Salmonella enterica remains the key cause of salmonellosis in poultry, causing high morbidity and mortality. Due to the unprecedented resistance of S. enterica to antibiotics, bacteriophages have emerged as a powerful alternative to conventional antibiotics treatment for salmonellosis.2. In this study, a strain was isolated from infected broiler chickens and whole-genome sequencing (WGS) identified the strain SFD-01 as S. enterica subsp. enterica. Bioinformatics analyses revealed that the genome was 4.6 Mb in size with 4559 coding sequences (CDS), 77 tRNAs and 4 rRNAs. Additionally, 119 virulence genes, 125 antimicrobial resistance genes, 5 mobile genetic elements, 2 prophages and multiple copies of pathogenicity islands (SPI) were identified in the genome.3. To address this, bacteriophage SF01 was isolated from wastewater near a chicken slaughterhouse against host strain SFD-01. Transmission electron microscopy revealed that the phage had an 85-nm icosahedral head and a 130-nm long contractile tail. The Felixounavirus SF01 exhibited high stability across pH 3-9. Phage lytic activity at a multiplicity of infection of 0.01 restricted the bacterial growth.4. Whole genome analysis (WGS) identified phage SF01 as a Felixounavirus with 88-kb genome composed of 174 CDS, 20 tRNA genes and with no lysogenic markers, resistance genes or virulence factors. The strict lytic potential of phage SF01 makes it a highly viable option for use in the potential biocontrol of the novel strain S. enterica subsp. enterica serotype 42:z4,z23.

Felixounavirus↗
PubMed1992

Human leukotriene C4 synthase expression in dimethyl sulfoxide-differentiated U937 cells.

Leukotriene C4 (LTC4) synthase was highly expressed in the human U937 monoblast leukemia cell line when differentiated into monocyte/macrophage-like cells by growth in the presence of dimethyl sulfoxide. The specific activity of LTC4 synthase in differentiated cells (399.0 +/- 84.1 pmol of LTC4 formed.min-1.mg-1) was markedly higher (10-fold; p less than 0.001) than in undifferentiated U937 cells (39.9 +/- 16.7 pmol of LTC4 formed.min-1.mg-1) or freshly isolated blood monocytes (21.5 +/- 4.8 pmol of LTC4 formed.min-1.mg-1). The increase in LTC4 synthase activity following dimethyl sulfoxide-induced differentiation was substantially higher than the increase observed for other proteins involved in leukotriene biosynthesis. LTC4 synthase activity was unaffected in U937 cells differentiated by growth in the presence of phorbol 12-myristate 13-acetate. The HL-60 myeloblast leukemia cell line expressed higher LTC4 synthase levels when differentiated into either neutrophil-like or macrophage-like cells by growth in the presence of dimethyl sulfoxide or phorbol 12-myristate 13-acetate (respectively), but reached a specific activity comparable only to undifferentiated U937 cells. Human LTC4 synthase was found to be a unique membrane-bound enzymatic activity completely distinct from alpha, mu, pi, theta, and microsomal glutathione S-transferases, as determined by differential detergent solubilization, chromatographic separation, substrate specificity, and Western blot analysis. An 18-kDa polypeptide was specifically labeled in membranes from dimethyl sulfoxide-differentiated U937 cells using azido 125I-LTC4, a photoaffinity probe based on the product of the LTC4 synthase-catalyzed reaction. Photolabeling of the 18-kDa polypeptide was specifically competed for by LTC4 (greater than 50% at 0.1 microM) but not by 100,000-fold higher concentrations of reduced glutathione (10 mM). Elevation of both the level of the specifically photolabeled 18-kDa polypeptide and of LTC4 synthase specific activity occurred concomitantly with dimethyl sulfoxide differentiation of U937 cells. We conclude that differentiation of U937 cells into monocyte/macrophage-like cells by growth in the presence of dimethyl sulfoxide results in high levels of expression of LTC4 synthase activity. Human LTC4 synthase is a unique enzyme with a high degree of specificity for LTA4 and may therefore be dedicated exclusively to the formation of LTC4 in vivo. An 18-kDa membrane polypeptide, specifically labeled by a photoaffinity derivative of LTC4, is a candidate for being either LTC4 synthase or a subunit thereof.

Cell Differentiation↗
PubMed1992

Comparison of regulatory and structural regions of the Xenopus laevis small heat-shock protein-encoding gene family.

We have isolated several unique Xenopus laevis hsp30 (encoding heat-shock protein 30) genomic clones, one of which contains two complete hsp30 genes (hsp30C and hsp30D), as well as the promoter and N-terminal coding region of a third gene (hsp30E). Nucleotide sequence and restriction enzyme analysis revealed that this gene cluster is different from a cluster isolated previously. The hsp30C and hsp30D genes encode proteins of approx. 24 kDa. In all, the hsp30 gene family contains a minimum of seven genes. The strand exchange and breakage of the duplication events which generated this gene family appear to have occurred within tracts of DNA which potentially can assume a Z-DNA conformation. Comparing the amino acid (aa) sequences of each known Hsp30 protein with bovine alpha-crystallin revealed a high degree of shared conservation of aa that constitute the major structural feature(s) of alpha-crystallin.

Amino Acid Sequence↗
PubMed1992

Prevalence of Plesiomonas shigelloides among diarrhoeal patients in Bangladesh.

The incidence of Plesiomonas shigelloides among diarrhoeal patients attending the Dhaka Treatment Centre of the International Centre for Diarrhoeal Disease Research, Bangladesh (ICDDR, B) from January through December 1987, has been reported. Using bile peptone broth (pH 8.8) as an enrichment medium and Salmonella-Shigella agar to isolate the organism, P. shigelloides was isolated from 838 (6.4%) of 13,142 patients, 523 (4.0%) of whom had no other pathogen isolated. The percentage of isolation was higher from stool (9.2%) than from rectal swab (5.9%) specimens (P < 0.005). The incidence of P. shigelloides was higher among male (64.0%) than female (36.0%) patients (P < 0.005). Isolation was highest among children less than five years. P. shigelloides was isolated most often in March (11.0%) and September (7.7%), indicating two seasonal peaks of incidence before and after the monsoons. All the strains were uniformly sensitive to chloramphenicol, furazolidon, gentamicin and trimethoprim-sulfamethoxazole. Sensitivity of the organism to ampicillin and tetracycline was 27.0% and 89.0%, respectively. This indicates that P. shigelloides may be an important agent of diarrhoea in our patient population.

Adolescent↗
PubMed1992

Neopterin concentrations in serum and cerebrospinal fluid in HTLV-I infected individuals.

The concentration of neopterin was measured in serum samples taken from individuals infected with HTLV-I: 5 from asymptomatic individuals, 1 from a patient with adult T-cell leukaemia and 30 from patients with tropical spastic paraparesis (TSP). In addition, cerebrospinal fluid (CSF) was available from 22 of the TSP patients and neopterin concentrations were determined in these. Elevated levels of neopterin were found in only 3 of the 36 HTLV-I-positive serum samples, all from TSP patients, but significantly elevated neopterin levels were observed in 12 of the 22 CSF samples. The localisation of the elevated neopterin concentrations to the CSF of patients with TSP suggests a marked degree of activation of the cell-mediated immune system intrathecally. This provides further evidence in favour of powerful immune mechanisms operating centrally in the pathogenesis of TSP.

Biopterins↗
PubMed1992

Amyloid enhancing factor activity is associated with ubiquitin.

Crude amyloid enhancing factor (AEF) drastically reduces the pre-amyloid phase on passive transfer and induces amyloid deposition in the recipient mice in 48-120 h. We attempted to purify AEF from murine amyloidotic liver and spleen extracts by using gel filtration, preparative sodium dodecyl sulphate-polyacrylamide gel electrophoresis and ion exchange chromatography and isolated a 5.5 kDa peptide. In the mouse bioassay, this peptide induced accelerated splenic AA deposition in a dose-dependent manner. Based on structural, electrophoretic and immunochemical criteria the peptide was identified as ubiquitin. A polyclonal rabbit anti-bovine ubiquitin IgG antibody (RABU) abolished the in vivo AEF activity of crude murine AEF in a dose-dependent manner. Monomeric ubiquitin and its large molecular weight adducts were isolated from crude AEF using cyanogen bromide-activated sepharose conjugated to RABU and size exclusion chromatography methods. These were assayed and were found to possess AEF activity. Furthermore, increased levels of ubiquitin, a phenomenon similar to that of AEF, were detected by immunocytochemistry in mouse peritoneal leucocytes prior to and during amyloid deposition. Since AEF shares a number of biological and functional properties with ubiquitin, we suggest a possible role of ubiquitin as an AEF, and that serum amyloid protein A and ubiquitin, the two reactants generated during inflammatory stress conditions, may converge to induce AA amyloid deposition.

Acute-Phase Reaction↗
PubMed1992

Experience with schistosomiasis in renal transplantation.

Schistosomiasis involving the urinary tract has only occasionally been reported in North American literature and rarely from American hospital experience. Chronic infection may result in numerous abnormalities of the urinary tract which may interfere with the function of a transplanted kidney. Our institution has performed a number of renal transplants in patients who are from countries where schistosomiasis is endemic. Six patients in our group had evidence of schistosomal disease during their pretransplant evaluation and were appropriately treated. None of these patients had postoperative complications attributable to the schistosomal disease. We recommend that all patients who are from areas where urinary schistosomiasis is endemic undergo a cystoscopic examination and bladder biopsies in addition to the routine pretransplant urologic evaluation.

Adult↗
PubMed1992

Renal scanning 99mTc diethylene-triamine pentaacetic acid glomerular filtration rate (GFR) determination compared with iothalamate clearance GFR in diabetics. The Collaborative Study Group for The study of Angiotensin-Converting Enzyme Inhibition in Diabetic Nephropathy.

Traditionally, creatinine clearance is used as an estimation of the glomerular filtration rate (GFR) because of its relative ease and low cost. Errors in collection limit its usefulness. Estimation of GFR using 99mTc diethylene-triamine pentaacetic acid (Tc-DTPA) by direct scintigraphic determination of fractional radionuclide accumulation within each kidney does not require blood or urine sampling, takes 10 to 15 minutes to perform, and has been reported to give a GFR that correlates with 24-hour urinary creatinine clearance (CC) in hospitalized patients (r = 0.95). To assess its usefulness in the outpatient diabetic with nephropathy, 24 patients with type I diabetes underwent 56 iothalamate clearances during water diuresis and 56 simultaneous Tc-DTPA GFR estimations. GFR was also estimated from 24-hour urinary CC, 100/creatinine, and by the formula of Cockcroft and Gault. Tc-DTPA GFR estimation by direct renal scanning correlated relatively poorly with iothalamate GFR (r = 0.74) in this patient population when all levels of iothalamate GFR were compared (n = 56), but improved (r = 0.80) when iothalamate GFR values greater than or equal to 120 mL/min were excluded from analysis (n = 45). Given all levels of iothalamate GFR, the best correlation was obtained with the estimation using the equation of Cockcroft and Gault (r = 0.86).

Adult↗
PubMed1992

Image normalization and background subtraction in T1-201/Tc-99m parathyroid subtraction scintigraphy. Effect on lesion detection.

The authors have developed two computer algorithms for T1-201/Tc-99m parathyroid subtraction scintigraphy that was performed on patients who subsequently underwent surgical exploration of the neck. Both methods employed a region-of-interest drawn around the thyroid/parathyroid glands for image realignment. The first algorithm normalized the Tl-201 and Tc-99m images using the ratio of maximum counts over the thyroid in each image. The second computer algorithm incorporated Tl-201 image background correction and normalization by the average of the ratios of maximum counts computed over each quadrant in both images. In 10 patients with confirmed parathyroid adenomas or hyperplasia, the first method yielded a 44% sensitivity. Upon reanalysis with the second algorithm, the sensitivity improved to 100%. Subsequently, in a total of 22 patients with 30 abnormal glands analyzed with the second algorithm, a sensitivity of 80% (94% for adenoma and 62% for hyperplasia) was achieved, with a specificity of 91%, as confirmed by surgery.

Algorithms↗
PubMed1992

Naturally occurring SLE anti-DNA antibodies recognize unique conformation on DNA-lysine photoadduct.

Native calf thymus DNA has been covalently modified with lysine under UV-A light. Human autoantibodies on purification through affinity column of native DNA linked to polylysyl-Sepharose 4B showed almost equal recognition of DNA and photoadduct. The recognition of DNA-lysine photoadduct by the affinity-purified autoantibodies might be helpful in understanding their origin in SLE vis-à-vis the role of positively charged amino acids in the pathogenesis of autoimmune diseases.

Animals↗
PubMed1992

The pharmacokinetics of perindopril and its effects on serum angiotensin converting enzyme activity in hypertensive patients with chronic renal failure.

1. Perindopril, an orally active angiotensin converting enzyme inhibitor, was given to 23 hypertensive patients with stable chronic renal failure for 15 days. The dose of perindopril was 2 or 4 mg once a day according to the degree of renal failure. The creatinine clearance of the patients ranged from 6 to 67 ml min-1 1.73 m-2. The pharmacokinetics of perindopril and perindoprilat, its active metabolite, were studied after acute and chronic administration of perindopril. 2. The drug was well tolerated and creatinine clearance was unaltered by treatment. 3. In both groups, steady-state was reached within 3 days of chronic treatment. 4. After both acute and chronic drug administration renal impairment had no effect on perindopril pharmacokinetics but the pharmacokinetics of perindoprilat were altered significantly. After chronic administration the serum accumulation ratio was 1.81 in patients with mild renal failure and 5.35 in patients with severe renal failure. Chronic administration did not modify the renal clearance of perindoprilat nor its elimination half-life. 5. A significant correlation between the renal clearance of perindoprilat and creatinine clearance was observed (r = 0.87 first dose, r = 0.83 last chronic dose). 6. A non-linear relationship between serum perindoprilat concentration and inhibition of angiotensin converting enzyme was described by a modified Hill equation. Values of IC50 were 1.11 +/- 0.07 micrograms I-1 (mean +/- s.d.) in patients with severe renal failure and 1.81 +/- 0.20 micrograms l-1 in patients with moderate renal failure. Chronic administration increased maximal inhibition and decreased the time to maximal inhibition only in patients with severe renal failure.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1992

HTLV-I infection and neurological disease in Rio de Janeiro.

Fifty patients with chronic neurological diseases attending a clinic in Rio de Janeiro, Brazil, were examined for evidence of HTLV-I infection. Fifteen of 27 with progressive paraparesis of obscure origin had antibodies to HTLV-I in high titre in their serum samples, and 10 of 13 studied had antibodies in their cerebrospinal fluid. The clinical features of the antibody positive patients were similar to those of patients with HTLV-I associated myelopathy from other countries except that half of the Brazilian patients were white. Seven patients had multiple sclerosis and one of these had antibodies to HTLV-I in the serum. None of the eight patients with motor neuron disease and four with polymyositis had HTLV-I antibodies in their serum samples.

Africa↗
PubMed1992

Pheochromocytoma and pregnancy: report of three cases.

Three cases of pheochromocytoma associated with pregnancy are reported. Two patients had adrenal pheochromocytoma coexistent with normal pregnancy and one patient had a bladder pheochromocytoma coexistent with molar pregnancy (gestational trophoblastic disease). The diagnosis was made antenatally in the two normal pregnancy patients, both underwent planned tumor resection, one at mid-trimester, complicated by postoperative miscarriage, while the other had tumor resection during cesarean section at term. Bladder pheochromocytoma, preoperatively mistaken for invasive trophoblastic tumor, was resected at the time of planned abdominal hysterectomy for molar pregnancy, pheochromocytoma was recognized only after microscopic study of the resected bladder tumor. The three patients survived with no evidence of disease.

Adrenal Gland Neoplasms↗
PubMed1992

Antibodies against free radical modified native DNA recognize B-conformation.

Hydroxyl radical, a prominent entity of reactive oxygen species, is known to modify cellular DNA and has been implicated in several human diseases. In the present studies, the radical was generated by exposure of hydrogen peroxide to 254 nm light in the presence of native calf thymus DNA. Single strand breaks, decrease in Tm and modification of adenine and thymine were some of the modifications observed in nDNA. Antibodies induced in experimental animals against the modified DNA were immunogen specific. These antibodies also recognize native B-conformation. It was observed that naturally occurring anti-native DNA autoantibodies from SLE sera recognize modified DNA in direct binding and competition ELISA. Gel retardation assay reiterated the formation of immune complexes between induced antibodies and DNA fragments of around 300 bp (B-conformation). The possible significance of these findings in the etiology of SLE has been discussed.

Animals↗
PubMed1992

Efficacy of two temephos formulations against Chironomus salinarius (Diptera: Chironomidae) in the saltwater lagoon of Venice, Italy.

Two formulations of the organophosphorus insecticide, temephos (Abathion Granulare, 1% AI granular and Tambro Compresse, 2% AI tablet) were evaluated against Chironomus salinarius midge larvae in 50 x 50 m experimental plots in the saltwater lagoon of Venice, Italy. Each formulation was applied at 0.2 and 0.4 kg AI/ha. Abathion Granulare produced 56 to 73% larval reduction at 0.2 kg AI/ha and 69 to 83% reduction at 0.4 kg AI/ha during 3 wk after treatment. Abathion Granulare lost effectiveness at 4 wk after application at both rates. Posttreatment larval reductions resulting from Tambro Compresse applications ranged from 77 to 86% for 3 wk, and 82 to 92% for 4 wk at rates of 0.2 and 0.4 kg AI/ha, respectively. The tablet formulation (Tambro Compresse) gave better control of C. salinarius (magnitude and duration) than the granular formulation (Abathion Granulare) in these evaluations.

Animals↗
PubMed1992

Shoulder dystocia: an obstetrical nightmare.

A nine-year review of 103 cases of shoulder dystocia identified obesity, diabetes mellitus and post-datism as important predisposing risk factors. There was a positive correlation with birthweight. Abnormal labour patterns were invariably absent and perinatal outcome was disastrous. The best strategy is to anticipate and avoid this obstetrical emergency.

Adolescent↗
PubMed1992

Resin-bonded bridges: 2. Treatment planning, clinical gases and failures.

This is the second paper in the two-part series which considers the developments and clinical techniques of resin-bonded bridges with the emphasis on methods for increasing success from a functional and aesthetic view point. Part 1 focused on the development and types of resin-bonded bridge and tooth preparation. This article describes the clinical application of this type of bridge and discusses failures.

Adolescent↗