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Biomedical subjects

H Shaikh

Publications and source records attributed to H Shaikh.

At least 19 recordsLinked to original sources

Changing patterns and re-distribution of antigen in poorly differentiated carcinomas: its implications in tumour diagnosis.

The variability of expression of tumour-associated antigens via either antigenic heterogeneity or antigenic modulation presents a basic problem in immunohistochemical diagnosis of poorly/undifferentiated tumours. This work was designed to study antigenic expression on human resected epithelial tumours by a panel of most widely used antibodies (EMA, CEA, AUAI & Cytokeratin) in relation to tumour differentiation and polarization. It was observed that poorly differentiated carcinoma with loss of polarity show homogeneous membrane staining (with antibodies against EMA, CEA & AUAI) in contrast to either apical (luminal) or basolateral membrane staining in well differentiated counterparts. Biochemical studies have shown that apical and basolateral epithelial cell membrane domains have a characteristic set of glycoproteins. Tight junctions are essential for maintaining this functional polarization. It was concluded that structural and functional abnormalities of tight junctions in poorly differentiated carcinomas results in loss of polarity with progressive invasion of the cell surface by antigenic glycoprotein and resultant homogeneous individual cell antigenic expression in poorly differentiated carcinomas. This study demonstrates that antigenic expression on tumour cells is not static, but dynamic and heterogeneity of antigenic expression may well be due to biological factors such as spatial configuration of the lesion.

Adenocarcinoma

Immuno-histochemical analysis of estrogen receptors on the malignant gallbladder tissue.

Sex steroids play an important part in the functioning of normal gallbladder, formation of gallstones and possibly in the pathogenesis of gallbladder cancer. Steroids receptors have been previously demonstrated on normal and malignant gall bladder tissues. To study this phenomenon further, we correlated clinicopathological features and survival with estrogen receptor (ER) status of the tumour in 30 patients with histologically-proven adenocarcinoma of the gallbladder. Estrogen receptor assay was performed immuno-histochemically utilizing Universal Immunoperoxidase Staining Kit. Tumor tissue was obtained either surgically or with fine needle aspiration of the gallbladder mass. There were 27 females and 3 males. Eighteen patients had estrogen receptors expressed on the malignant tissue, 12 were negative. Comparison of clinicopathological characteristics and survival between the two groups demonstrated no significant difference in gender, mean age, marital status and parity. Similarly, presence of gallstones, histologic grade or survival did not correlate with the estrogen receptor status. There is, however, a trend in favour of poorly differentiated tumors being more often receptor negative. Further studies are necessary to elucidate the biologic significance of these receptors.

Adenocarcinoma

Is carcinoma breast a different disease in Pakistani population?

Carcinoma of the breast tends to be different in coloured and white races. Is this pattern also expressed in Pakistani population? To answer this query we carried out a retrospectively study of breast cancer on 193 cases who were divided into 2 groups i.e. less than and more than 50 years age groups. In the former group, 93% tumours were of grades II or III and approximately 51% were estrogen receptors negative. In more than 50 years age group, 75% tumors were in grade II and III, with almost 37% being estrogen negative tumors. Majority (75%) of the patients had over 6 cms lump with equal number having positive lymph node status. All these factors point to the fact that besides presenting late, our population has additional unfavourable prognostic factors.

Adolescent

Clinicopathological features and management of immunoproliferative small intestinal disease and primary small intestinal lymphoma in Pakistan.

This study was performed to confirm the existence of immunoproliferative small intestinal disease (IPSID) in Pakistan. Clinicopathological features of 12 patients with histologically confirmed disease were analysed. Patients were mostly young males with median age of 24.6 years. Two thirds belonged to poor socioeconomic class. Main presenting features were chronic diarrhoea and weight loss. Eleven patients had radiologic evidence of malabsorption syndrome. Endoscopic findings of mucosal thickening, edema, and flattened villi were present in the majority. Patients had both secretory and non-secretory types of disease. Six patients presented with stage A disease. Four responded to antibiotics or steroids, although mucosal abnormalities persisted in three. Two stage A patients evolved into stage C disease, one was lost to follow-up, the other is alive with disease. Three patients presented with stage B disease. Two responded completely to chemotherapy, the third refused treatment and expired after 16 months. Three patients had stage C disease at diagnosis. They received aggressive combination chemotherapy and remain in complete remission with a median follow-up of 2.2 years. This is the first series of patients with IPSID reported from Pakistan. Clinicopathological features and therapeutic results are consistent with the experience elsewhere. Increased awareness may result in early diagnosis and better management.

Adult

Amoebic appendicitis--a rare entity.

Appendectomy is the most common surgical procedure performed in routine general surgical practice. However, not all the appendices removed, are submitted for histopathological examination in this part of the world. We reviewed 1400 appendices received by our department from within our hospital and from outside the hospital. Of these 13 cases were reported as amoebic appendicitis. These patients did not have any different clinical presentation from the patients who were reported as acute appendicitis without amoebae. Microscopically these appendices had minimal neutrophil polymorph infiltration accompanied by tissue necrosis and amoebic trophozoites within the appendiceal wall. After histological diagnosis, different tests (IHA and stool examination) were done to exclude a possibility of secondary involvement of the appendix, on 8 patients from our hospital which were negative, thus confirming that these patients had primary appendiceal involvement. Hence we recommend that all the appendices removed should be subjected for histological examination, since ths may help in subsequent management of these patients.

Adolescent

Immunohistochemical estrogen receptor determination in human breast carcinoma: correlation with histologic differentiation and age of the patients.

An immunohistochemical assay for the measurement of estrogen receptor (ER) has been evaluated on 290 consecutive human breast biopsy and mastectomy specimens in the year 1992 at The Aga Khan University Hospital laboratories. Immunohistochemical localization of estrogen receptor on frozen/paraffin section was scored in a semi-quantitative fashion incorporating both the intensity and the distribution of specific staining. Histologic grading of the tumour was performed according to Bloom's method. In this study, 21% of the tumours were estrogen receptor negative, 15% were weak positive, 25% intermediate positive and 39% strong positive. Fifty percent of the well differentiated tumours showed strong ER positivity against 27% of the poorly differentiated tumours. Seventy eight percent of all negative estrogen receptors were in patients younger than 50 years of age (pre-menopausal group), while 52% of strong estrogen receptor positivity was observed in patients older than 50 years (post- menopausal). This study demonstrates the value of immunohistochemical method to determine the ER status in patients with advanced breast cancer.

Adult

Yet another cause of chronic viral hepatitis?

The clinical features, course and histology of liver in 20 patients; mostly middle aged to elderly females, closely resembling chronic Non A Non B hepatitis is presented. They presented quite late in their disease and therefore, complications such as variceal bleeds, ascites and encephalopathy were frequent. Our patients were negative for hepatitis B and C virus serology. Metabolic and immune causes of chronic liver disease were also ruled out. To the best of our knowledge, this is the first study of its kind elaborating the clinical features, course and histology of liver in chronic Non B Non C hepatitis and raises a number of questions as to the nature of the infecting virus and the epidemiology of disease.

Chronic Disease

Adenomyosis in Pakistani women: four year experience at the Aga Khan University Medical Centre, Karachi.

As part of a quality assurance programme at the Aga Khan University Medical Centre, Karachi, Pakistan, all hysterectomy specimens were reviewed from January 1986 to December 1989. Adenomyosis was found in 237 of the 419 (56.5%) specimens studied. Of these 237 patients, 232 (97.9%) were parous and 196 (82.8%) were in the fourth and fifth decades of life. This high prevalence in parous women aged 40-59 years was significant. Fibroids, cervicitis, and endometrial hyperplasia were the most common associated diagnoses. Of all the associations studied, only endometrial hyperplasia was significantly more prevalent in the group with adenomyosis. Adenomyosis was stated as an indication for surgery in 69 patients and was confirmed by histopathology in 49 (71%). Preoperative suspicion of adenomyosis was present in 49 (20.6%) patients of all those ultimately found to have the disease. There is a high prevalence of adenomyosis in the population studied, which indicates that the condition may have been underdiagnosed in the past, especially as it is difficult to diagnose without surgery and hysterectomy is currently the only treatment.

Adult

Characterization by enzyme-linked immunosorbent assay using subgroup- and serotype-specific monoclonal antibodies of human rotavirus obtained from diarrheic patients in Bangladesh.

By enzyme-linked immunosorbent assay with group A-, subgroup-, and serotype-specific monoclonal antibodies (MAbs), we tested 414 stool specimens collected from pediatric and adult patients hospitalized with acute gastroenteritis between January and June 1988. Of 414 specimens tested, 124 (30%) were positive for group A rotavirus. The subgroup was determined in 110 specimens (88.7%); 16.1% were subgroup I, and 72.6% were subgroup II. Two specimens reacted with both subgroup I- and subgroup II-specific MAbs. Serotype determinations showed that serotype 1 (38.4%) was predominant over serotypes 2 (28.2%), 3 (2.5%), and 4 (23%). Three specimens reacted with more than one serotype-specific MAb. While the frequency of serotype 1 was highest in the two hospitals in Mymensingh, serotype 2 was most prevalent in one hospital in Dhaka. All human rotavirus strains with subgroup I and serotype 2 specificities showed a short electropherotype, and all but one strain with subgroup II and serotype 1, 3, or 4 specificities exhibited a long electropherotype.

Acute Disease

Prevalence and pathology of helminth parasites in domestic ducks of Bangladesh.

Parasitism in waterfowl is a very common phenomenon. Two detailed check lists of helminth parasites of waterfowl are available (Lapage, 1961; McDonald, 1969) and many of these parasites are reported to occur in domestic ducks. However, the pathological significance of most of them is unclear. In a preliminary study, Qadir (1979) recorded 13 species of helminths from domestic ducks of Bangladesh. The present paper reports on the prevalence and pathological effects of helminth infections in domestic ducks (Anas platyrhynchos domesticus) of Bangladesh under natural conditions and on their incidence in two age and sex groups of ducks.

Animals

Fungal mastitis. Case report.

Fungal (cryptococcal) mastitis in a young woman seemed to be a systemic manifestation of the infection, since it recurred contralaterally within 4 months. Diagnostic problems are discussed. Only two previous reports of deep mammary mycosis were found. In addition to excision, ketoconazole is recommended to prevent recurrence or serious complications.

Adult

The value of colonoscopy in schistosomal, tuberculous, and amebic colitis. Two-year experience.

Forty-six patients were diagnosed as having schistosomal, tuberculous, or amebic colitis over a two-year period using colonoscopy and biopsy. Both schistosomal and tuberculous colitis could be diagnosed by characteristic endoscopic and histologic features in the majority of cases. Colonoscopy provided the added advantage of endoscopic polypectomy at the diagnostic session itself. The yield of granulomas in tuberculous lesions was 100 percent, although acid-fast bacilli could not be recovered from any. The endoscopic picture of amebic colitis often resembles that of inflammatory bowel disease; hence endoscopic biopsies are of paramount importance in establishing a correct diagnosis, especially in developing countries where both diseases exist with considerable frequency.

Adult