Biomedical subjects
Publications and source records attributed to M S Siddiqui.
A rare sport injury having patellar fracture and anterior cruciate ligament avulsion fracture is being reported. This case was noteworthy as it involved rare combination of two separate injuries often seen in sportsmen. Our experience with operative intervention and postoperative rehabilitation with a supervised physiotherapy regimen has yielded good results.
OBJECTIVE: To know the frequency of breast diseases in Pakistani females. METHODS: A retrospective analysis of 3279 breast specimens received over a period of 4 years (1993-1996) at the department of pathology, the Aga Khan University Hospital. RESULTS: Out of a total of 3279 breast specimens, common breast lesions included infiltrating duct carcinoma 37%, followed by fibro adenoma 16.95%, fibrocystic change 13.96%, mastitis 6.83% and duct ectasia 5.33%. Majority of the cases of infiltrating duct carcinoma were encountered in the 5th and 6th decades of life. Tumour size was 2 or >2 cms. in 93% of cases and 40% of them showed 3 or >3 positive lymph nodes. Grade I tumours were 11.38%, grade II 59.17% and grade III tumours 29.47%. Correlation of grade with lymph node metastases (3 or >3+ve nodes) showed 15 cases (1.53%) of grade I, 178 cases (18.25%) of grade II and 68 (6.97%) cases of grade III tumours. CONCLUSION: This study shows that in Pakistani females, the most commonly encountered lesion in carcinoma of the breast followed by the benign lesions such as fibro adenoma, fibrocystic disease & others. Breast carcinoma occurs at a younger age group with predominance of high-grade lesions and with frequent lymph node metastasis.
The posterolateral tunnel on the superior surface of the first cervical (atlas) vertebra is of normal occurrence in monkeys and other lower animals, but its presence in the form of a tunnel-like canal, for the passage of the third part of the vertebral artery over the posterior arch of the human atlas vertebra is not reported. The aim of the present study was to detect the presence of such a canal, in addition to other types of ponticuli (little bridges) reported by earlier investigators, in macerated atlas vertebrae and routine cadaveric dissections. The posterolateral tunnel was detected in 1.14%, and the posterior and lateral ponticuli in 6.57 and 2% of vertebrae. Probably the bony roof of the posterolateral tunnel serves the purpose of additional lateral extension for the attachment of the posterior atlanto-occipital membrane in quadrupeds, where the load of the head is supported by the extensor muscles of the neck, ligaments and posterior atlanto-occipital membrane. In man, where the weight of the head is borne by the vertical loading of the superior articular process of the atlas, the roof of the tunnel has disappeared.
We investigated the effects of IFN-gamma-inducing factor (IL-18) in a ragweed (RW) mouse model of allergic asthma. Administration of IL-18 in conjunction with allergic sensitization and challenge in wild-type, but not IFN-gamma -/- mice, inhibited the bronchoalveolar lavage (BAL) eosinophilia induced by RW challenge, and increased serum levels of RW-specific IgG2a and production of IFN-gamma from splenocytes cultured with RW, indicating a critical role for IFN-gamma in mediating these effects. Paradoxically, the same treatment schedule in WT mice increased serum levels of RW-specific IgE and IgG1, and production of IL-4 and IL-5 from splenocytes cultured with RW. When the effects of the same IL-18 treatment schedule were allowed to mature for 3 wk, the inhibition of lung eosinophil recruitment was replaced by augmentation of lung eosinophil recruitment. In another experiment, IL-18 administered only with allergic sensitization increased BAL eosinophilia and lung expression of IL-5 and IFN-gamma, while IL-18 administered only with RW challenge decreased BAL eosinophilia and increased lung IFN-gamma expression, while lung expression of IL-5 remained unchanged. IL-18 administered without RW or adjuvant to naive mice increased total serum IgE levels. Finally, intrapulmonary administrations of IL-18 plus RW in naive mice dramatically increased Th2 cytokine production, IgE levels, eosinophil recruitment, and airway mucus, demonstrating induction of allergic sensitization. This is the first report demonstrating that IL-18 promotes a Th2 phenotype in vivo, and potently induces allergic sensitization. These results suggest that IL-18 may contribute to the pathogenesis of allergic asthma.
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OBJECTIVE: To study the morphological features in breast carcinoma which have proven prognostic value. METHODS AND SETTING: A retrospective analysis of 572 mastectomy specimens received over a period of three years at the department of pathology, The Aga Khan University Hospital. RESULTS: A total of 572 mastectomy specimens were analyzed which were received over a period of three years. Most of the patients were in the 5th and 6th decades of life. The mean age at diagnosis was 48 years. The most common tumour was infiltrating ductal carcinoma (81%). Tumour size was > 2 cms. in 80% of the cases. According to Modified Bloom and Richardson system most of the tumours were in grade II (65%) followed by grade III (24%). The number of cases with > 3 lymph node metastasis was significantly higher (70%) in tumours of > 2 cms size. High grade tumours also showed increased number of lymph node involvement. CONCLUSION: In Pakistani females breast carcinoma occurs at a younger age group. They are of large size at the time of presentation and show more frequent axillary lymph node metastasis. Infiltrating ductal carcinoma is the most common type of tumour with predominance of high grade lesions.
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OBJECTIVE: To observe the spectrum of non-Hodgkin's lymphomas involving the central nervous system including morphological subtypes and immunophenotypic status. SETTING: Retrospective analysis of eleven years (1986 to 1996) data from surgical pathology files of Department of Pathology. RESULTS: Forty-three cases of non-Hodgkin's lymphomas were diagnosed during the period of eleven years (from 1986 to 1996), all of which were diffuse types. A total of 1177 Central Nervous CNS biopsies were examined, out of which 937 cases were diagnosed as CNS neoplasms, the remaining were non-neoplastic in nature. Among 937 CNS neoplasms, 43 cases (4.6%) were reported as non-Hodgkin's lymphomas. As most of the cases were outside referrals, the primary or secondary nature of the lymphomatous process could not be assessed. Seventeen cases were intracranial, while 26 cases were spinal in location. Majority of the intracranial lymphomas were biopsied from the cerebrum (12 cases). Male to female ratio was 1:2. The median age for intracranial lymphomas was 50 years and for spinal lymphomas 29 years. There were 16 cases (37%) of diffuse large cell lymphomas; 7 cases (16%) of diffuse mixed small and large cell lymphomas; 3 cases (7%) of diffuse large cell immunoblastic lymphomas; 2 cases (4.6%) of lymphoblastic lymphomas and diffuse small non-cleaved cell lymphomas and one case of small lymphocytic lymphoma and diffuse small cleaved cell lymphoma. One case of T cell rich B cell lymphoma was also diagnosed in the thoracic spine as primary extranodal lymphoma. Eight cases were unclassifiable and in 2 cases the features were suggestive of lymphoma. Immunophenotypic analysis was performed in 20 cases, however, in 2 cases the results were inconclusive. Fifteen cases (83%) showed immunoreactivity for B cell markers and 3 cases showed T cell phenotype out of which one case was lymphoblastic lymphoma. CONCLUSION: CNS lymphomas were uncommon tumors and comprised 4.6% of the total CNS neoplasms in our study. Moreover, these CNS lymphomas accounted for 2.2% of the total non-Hodgkin's lymphomas, including both nodal and extranodal. There was a higher incidence of location of these lymphomas within the spinal cord than brain. Most of the lymphomas were of intermediate or high grade (75%) according to the working formulation. Immunophenotypical status revealed B-cell phenotype in 84% of the lymphomas, in which it was tested (JPMA 50:141, 2000).
To overcome the diagnostic dilemma in proliferative conditions of the liver which sometimes pose a problem to the working pathologist especially when the material is inadequate, a special staining technique (AgNOR) has been applied. By using this technique, nucleolar organizer regions were counted which determine the proliferative status of the cells. This prospective study included 65 cases of randomly selected liver core and fine needle aspiration biopsies. AgNOR staining was performed on formalin-fixed, paraffin-embedded tissue sections NOR dots were counted in 100 randomly selected hepatocytes at x100 oil immersion objective, and the mean count per cell was calculated for each case. Statistical analysis was done by using the Mann Whitney U test. AgNOR count results were later compared with the histologic diagnosis. The study revealed a gradual increase in mean AgNOR counts from normal liver through cirrhosis to hepatocellular carcinoma. The difference in NOR counts was significant in these three groups. The hepatocellular carcinomas were graded according to the Edmondson-Steiner histological grading system. The Grade I hepatocellular carcinomas show AgNOR counts ranging between 5-6/cell, a score which is much higher than in the normal liver, where it ranges between 1.2-2.0/cell. This technique can be used to assess the lesions where the distinction between normal liver and Grade I hepatocellular carcinoma is difficult with the use of routine methods. AgNOR counts in normal liver and chronic hepatitis cases were insignificant, but there was an appreciable difference between cases of chronic hepatitis, cirrhosis and hepatocellular carcinoma. In view of the results of this study, the AgNOR staining method is found to be a useful diagnostic tool to differentiate between normal liver, cirrhosis and hepatocellular carcinoma and also to precisely discriminate between cases of normal liver and Grade I hepatocellular carcinoma.
OBJECTIVE: This study was done to evaluate the pediatric undifferentiated small round cell tumors with immunohistochemical staining. SETTING: The present study included consecutive cases of small round cell tumors which were diagnosed in children (< 15 years) in the section of Histopathology at the Aga Khan University Hospital, Karachi during the period of two years. METHODS: The group of undifferentiated small round cell tumors were evaluated immunohistochemically by using a panel of antibodies on sections from routinely processed, formalin fixed, paraffin embedded tissue blocks. RESULTS: The category of undifferentiated small round cell tumors included rhabdomyosarcoma (23.2%), primitive neuroectodermal tumor (17.9%), non-Hodgkin's lymphoma (16.1%), neuroblastoma (14.2%), Ewing's sarcoma (10.7%) in order of frequency. Osteosarcoma (Small cell variant), retinoblastoma and medulloblastoma comprised 1.8% each. In seven cases (12.5%), the immunohistochemical analysis was inconclusive. CONCLUSION: Immunohistochemistry is a very valuable diagnostic tool which helps in distinguishing the undifferentiated tumors especially small round cell tumors. The immunohistochemical staining needs to be performed routinely for undifferentiated tumors in diagnostic histopathology.
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Tuberculosis is still one of the most widespread infection known to mankind. Although lung is the predominant site of disease, a sizeable population in Pakistan gets intestinal disease. Clinical presentation, radiologic and endoscopic examination provide clues to the diagnosis. However, a definitive diagnosis requires biopsy material with granulomas and/or caseation complemented by acid fast staining and culture. There are many occasions when biopsy material is scanty and even in some intestinal resection cases histologic evaluation fails to confirm or rule out tuberculosis. Therefore, an investigation was conducted to assess the efficacy of PCR in the detection of mycobacterial DNA in paraffin embedded intestinal tissue. In this study 12 histologically confirmed cases of intestinal tuberculosis and 2 cases with non specific inflammation but clinically suspected for abdominal tuberculosis were selected. One case of rectal polyp was included to serve as a negative control. M. tuberculosis DNA was amplified in 8 out of 12 histologically confirmed cases and in 2 cases diagnosed with non specific inflammation. Amplified products were obtained in 6 out of 10 PCR positive specimens with IS6110 region specific primers while 4 samples were negative, suggesting the absence of insertion sequence 6110 in these strains. However, amplification was obtained in these negative specimens with a second primer pair confirming them as M. tuberculosis complex species. On the basis of this study we conclude that; (1) Processed and paraffin embedded tissue material is suitable for PCR analysis, (2) PCR assay can be used to complement the diagnosis of intestinal tuberculosis especially in situations where a definite conclusion can not be drawn by conventional methods, (3) M. tuberculosis species lacking insertion sequence 6110 element are present in our population. Therefore, several primer pair sets should be included when applying PCR for the detection of mycobacterial DNA.
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Adult female rabbits were given daily intramuscular injections of 0.5 microgram of oestradiol diproprionate for four weeks. Weekly drum-stick counts were made from their blood smears and percent incidences of drum-sticks in the neutrophils was recorded. A highly significant increase in the drum-stick counts compared to the control animals was noted after one week's treatment with the oestrogen. Subsequent values after 2nd, 3rd and 4th week's treatment were not significantly different from values obtained from the corresponding untreated animals. It was concluded that oestrogen produces only an initial increase in the drumstick count and subsequent continued treatment neither increases nor decreases the drum-stick counts significantly.