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Biomedical subjects

M A Ali

Publications and source records attributed to M A Ali.

At least 181 records · Page 10Linked to original sources
PubMed1988

Pineal and retinal photoreceptors in embryonic Rivulus marmoratus poey.

The development of pineal and retinal photoreceptors was studied in embryos of Rivulus marmoratus Poey from 0.2 to 0.7 incubation period. Photoreceptors in both these organs are developed and clearly divided into outer and inner segments at mid-incubation period, in addition retinal photoreceptors are arranged in a square mosaic. However, while retinal photoreceptors contain synaptic ribbons at this developmental stage pineal photoreceptors do not; although presynaptic electron densities are present. At 0.7 incubation period synaptic ribbons are present in basal processes of pineal photoreceptors, while those in retinal photoreceptors have lengthened. The sequence of the development of photoreceptor structure in pineal and retina is discussed.

Animals↗
PubMed1987

Acute osteomyelitis of index finger caused by dog bite.

A forty-seven-year-old man was bitten by a dog on his left index finger. Despite initial antibiotic treatment, he developed acute osteomyelitis of the middle phalanx over the next three weeks. Pasteurella multocida and Bacteroides were isolated from the necrotic bone. Subsequently the infection was successfully treated by debridement and Tetracycline.

Animals↗
PubMed1987

Expression and nuclear envelope localization of biologically active fusion glycoprotein gB of herpes simplex virus in mammalian cells using cloned DNA.

Herpes simplex virus (HSV) is known to bud from the inner membrane of the nuclear envelope. The structural gene for the glycoprotein gB, which is essential for virus entry and cell fusion induced by HSV type 1, has been cloned in a transient expression vector containing the adenovirus major late promoter, tripartite leader sequence, and VARNA (a special RNA in adenovirus-infected cells) genes. Synthesis and glycosylation of glycoprotein gB was observed in COS-1 cells transfected with the vector containing the gB gene. Removal of a 3' fragment of the cloned gene resulted in the synthesis and secretion of a truncated gB glycoprotein. Immunofluorescence studies revealed that the expressed glycoprotein was localized in the nuclear envelope as well as in the cell surface. The expressed gB-1 glycoprotein was biologically active and induced fusion of cells to produce polykaryons. These data show that HSV glycoprotein gB expressed from cloned gene can be used as a model to study targeting of proteins into the nuclear envelope as well as cell fusion induced by the virus.

Animals↗
PubMed1986

Aspiration cytology of neuroblastoma. Light and electron microscopic correlations.

Fine-needle aspiration biopsy (FNAB) smears from 16 cases of neuroblastoma are reviewed, and various cytomorphologic features helpful in diagnosing this tumor are described. Cytoplasmic processes were present in ten cases, and pseudorosettes in three cases. Electron microscopic study of FNAB samples revealed that all diagnostically important features, such as cell processes, neurosecretory granules, and synaptic cell junctions, could be recognized. These findings indicate that FNAB studied by light and electron microscopy is an effective method for diagnosing neuroblastoma.

Biopsy, Needle↗
PubMed1985

Aspiration cytology of Ewing's sarcoma. Light and electron microscopic correlations.

Fine-needle aspiration biopsy specimens from 15 histologically proven cases of Ewing's sarcoma of the bone were studied by both light and electron microscopy. Large glycogen deposits in the Ewing's sarcoma cells could be easily recognized in smears stained routinely with Diff-Quik (American Scientific Product, McGraw Park, IL). These deposits appeared as punched-out clear spaces in the cytoplasm. Ultrastructurally the tumor cells could be divided into chief cells and dark cells. The chief cells were further categorized based on their nuclear morphologic features into cleaved, noncleaved, and intermediate cells. The dominant cell was noncleaved in eight, cleaved in three, and intermediate in four cases. All five tumors with abundant glycogen were composed predominantly of noncleaved cells. The tumor cells in aspiration material appeared to be irregular in shape, and some had cytoplasmic processes. In one tumor these processes were quite prominent; this caused some difficulty in differentiation from neuroblastoma.

Adolescent↗
PubMed1985

Mechanism of coupling periodate-oxidized nucleosides to proteins.

This paper describes a mechanism of coupling periodate-oxidized nucleosides to proteins. Each of the dialdehyde groups of a periodate-oxidized nucleoside is shown to couple to lysine residues on different protein molecules through Schiff bases, thereby cross-linking different protein molecules, forming a polymer. This is in contrast to the previous model in which nucleosides were suggested to couple to proteins through a morpholine structure. The cross-linked structure of the nucleoside-antigen, significantly different when compared to the native protein, may affect the specificity and the efficiency of antibody production.

Antibody Formation↗
PubMed1985

Fine-needle aspiration biopsy diagnosis of round cell malignant tumors of childhood. A combined light and electron microscopic approach.

A series of fine-needle aspiration biopsies (FNAB) from 76 children with round cell malignant tumors was studied by both light and electron microscopy. In 14 cases the material submitted for electron microscopy was inadequate, whereas in the remaining 62 biopsies a definitive diagnosis could be made. These included 29 malignant lymphomas, 8 neuroblastomas, 12 Ewing's sarcomas, 3 metastatic retinoblastomas, 3 Wilms' tumors, 3 rhabdomyosarcomas, and 4 unclassified tumors. The results from this study indicate that FNAB studied by light and electron microscopy can be effective in diagnosing small cell tumors in children.

Biopsy, Needle↗
PubMed1985

Hepatic tumors in Saudi Arabia. A practical approach to diagnosis.

All cases of liver tumor referred to the King Faisal Specialist Hospital and Research Centre in Saudi Arabia during 2.5 years were reviewed. Hepatocellular carcinoma, 104 cases, was considerably more common than metastatic carcinoma with unknown primary, 15 cases. Lymphoma presenting as liver tumor occurred in three cases and there were no cases of cholangiocarcinoma. There were only two cases of benign tumor, both hemangioma. Hepatocellular carcinoma was characterized by a male predominance of 6:1, positive hepatitis B surface antigen in 60%, presentation with an enlarged, hard liver in over 90%, a systolic-diastolic bruit over the mass in 45%, a single highly echogenic lesion in the right lobe on ultrasound in 80%, and rapid progression. The serum AST (aspartate aminotransferase, serumglutamic oxalacetic transaminase [SGOT]) was abnormal in 97% and was higher than the alanine aminotransferase (ALT) in 93% of cases compared with 17% in 100 consecutive cases of chronic active hepatitis. Sixty-six percent of patients with hepatocellular carcinoma had serum AFP greater than 200 ng/ml. Excluding five cases of germ cell tumor (none involving the liver), and pregnant patients, serum AFP was less than 200 ng/ml in all other patients in whom it was measured between 1979 and 1981. A practical approach to the diagnosis of hepatocellular carcinoma is outlined. Biopsy does not appear to be indicated in many cases of advanced hepatocellular carcinoma.

Alanine Transaminase↗
PubMed1985

Gastrointestinal malacoplakia in children.

Four children, whose ages ranged from 1 to 13 years, with malacoplakia of the gastrointestinal tract were treated at King Faisal Specialist Hospital between 1979 and 1983. All patients had either a preceding or a coexisting chronic illness. In one patient, malacoplakia was an incidental finding, while the remaining three patients presented with bloody diarrhea, abdominal pain, recurrent fever, and severe malnutrition. Colonoscopy in two patients revealed markedly inflamed and friable mucosa with focal ulceration alternating with patches of normal mucosa and pseudopolyposis. They were treated with antibiotics and cholinergic agonists. Three patients responded favorably, while one patient continued to have extensive active disease. Although the response to therapy is unpredictable, patients may respond if the treatment is continued on a long-term basis.

Adolescent↗
PubMed1985

Compound heterozygosity for two genotypes of alpha-thalassemia-2: hematological, biosynthetic and DNA studies.

Hemoglobin and DNA gene analyses were carried out in two Black Canadian families. In Family Q, both the parents and the brother were found to be heterozygotes for alpha-thalassemia-2 with the following alpha-genotypes: -alpha 3.7/alpha alpha, -alpha 4.2/alpha alpha and -alpha 4.2/alpha alpha, respectively. In Family C, the mother was found to be a homozygote for alpha-thalassemia-2 with the alpha-genotype of -alpha 3.7/-alpha 3.7. In both families, the propositi were compound heterozygotes for alpha-thalassemia-2 with the alpha-genotype of -alpha 3.7/-alpha 4.2. The propositus in Family C was also a sickle cell trait carrier. The usefulness of DNA gene analyses in family studies of hemoglobinopathy was discussed.

Adult↗
PubMed1985

Characterization of adenosine-bovine serum albumin immunogen and its antibodies.

Antibodies to adenosine were elicited in rabbits using a conjugate of adenosine (periodate oxidized) and bovine serum albumin as immunogen. The conjugate was found to be of a higher molecular size than the original protein, apparently due to the cross-linking of albumin molecules by the dialdehydes generated during the periodate oxidation of adenosine. It produced high titres of antibodies, which were 400-fold more reactive to adenosine-trialcohol than to adenosine, when measured by a nitrocellulose filter assay. In addition, a specific elution procedure for the isolation of hapten-specific antibodies is described.

Adenosine↗
PubMed1985

Polyclonal B cell hyperplasia associated with Epstein-Barr virus causing acute renal allograft failure.

Six weeks post cadaver renal transplantation, a patient developed a flu-like illness. Acute renal failure unresponsive to anti-rejection therapy occurred and he died four days later from Pneumocystis carinii pneumonia and Streptococcus viridans septicemia. Autopsy revealed a diffuse polymorphic polyclonal B cell infiltrate occupying most organs, including the allograft. Primary Epstein-Barr Virus (EBV) infection was established by 1) rising anti-EBV antibody titres; 2) the demonstration of EBV nuclear antigen in the infiltrate and 3) the presence of EBV specific DNA sequences in affected tissues. EBV associated polymorphic B cell hyperplasia can mimic rejection and result in acute allograft failure.

Antibodies, Viral↗