43 research outputs found
Keratinolytic activity exhibited in an indigenous non-dermatophytic fungus strain Cochliobolus lunatus isolated from Khairpur Sindh Pakistan
Keratins are the widely distributed fibrous proteins of our environment. Keratinase are proteolytic enzymes responsible for hydrolyzing insoluble keratin largely produced by microorganisms including fungi. The isolation, identification and characterization of a non-dermatophytic keratinolytic fungal strain of Cochliobolus lunatus from the soils of Khairpur Sindh Pakistan were reported. The temperature optimum for this strain production of the enzyme was 30°C, preferable carbon and nitrogen sources were glucose and gelatin respectively, optimum time for keratinase production was 9 days and the activity was suppressed by Ca2+ ions.Keywords: Keratinase, fungus, identification, characterizationAfrican Journal of Biotechnology Vol. 12(14), pp. 1669-167
Ex-vivo Raman spectroscopy mapping of lung tissue: label-free molecular characterisation of non-tumorous and cancerous tissues
Raman spectroscopy mapping was used to study ex vivo fresh lung tissues and compare to histology sections. The Raman mapping measurements revealed differences in the molecular composition of normal lung tissue, adenocarcinoma, and squamous cell carcinoma (SCC). Molecular heterogeneity of the tissue samples was well captured by the k-means clustering analysis of the Raman datasets, as confirmed by the correlation with the adjacent haematoxylin and eosin (H&E) stained tissue sections. The results indicate that the fluorescence background varies considerably even in samples that appear structurally uniform in the H&E images, both for normal and tumor tissue. The results show that characteristic Raman bands can be used to discriminate between tumorous and nontumorous lung tissues and between adenocarcinoma and SCC tissues. These results indicate the potential to develop Raman classifications models for lung tissues based on the Raman spectral differences at the microscopic level, which can be used for tissue diagnosis or treatment stratification
Detection of mycobacterium tuberculosis in paraffin embedded intestinal tissue specimens by polymerase chain reaction: characterization of IS6110 element negative strains
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
Endocrine cell dysplasia (nesidioblastosis): A relatively unrecognized entity in Pakistan?
Nesidioblastosis is quantitative as well as qualitative abnormality of pancreatic endocrine cells. There is scattering of small endocrine cell clusters arranged haphazardly rather than the peripheral location within the lobule1,2. Islet contours are irregular, tailing off into parenchyma3. These islets are present in intimate association with ducts forming ductuloinsular complexes1 We recently encountered a new born baby with signs and symptoms of endocrine cell dysplasia
Well differentiated hepatocellular carcinoma metastasizing to jaw and oral cavity within six months of primary diagnosis.
Clinico-morphological pattern of intracranial tumors in children
Objective: The objective of present study was to observe the histopathological pattern of intracranial tumors in children (\u3c 15 yrs) and to correlate the site of lesion along with the histological diagnosis. Setting: The study included consecutive cases of intracranial tumors diagnosed in children (\u3c 15 yrs.) in the section of histopathology at the Aga Khan University Hospital, Karachi during the period of three years. Methods:The initial histological evaluation of these lesions was performed on H and E stained section of paraffin embedded tissue. Special stains and immunohistochemical analysis was done whenever indicated. Results:During the study period, fifty-four cases of intracranial tumors were diagnosed in children. The age ranged from 1-1/2 years to 4 years with male to female ratio of 1.1:1. Astrocytoma comprised 39% of all intracranial tumors of childhood. Medulloblastoma (18.6%) ranked the second most prevalent brain tumor followed by empendymoma (13%), oligodendroglioma 7.5% while non-Hodgkin\u27s lymphoma, primitive neuroblastoma 3.7% and ganglioglioma 3.7% while non-Hodgkin\u27s lymphoma, primitive neuroectodermal tumors, mixed germ cell tumor, pineoblastoma, choroid plexus carcinoma and malignant meningioma constituted 1.8% each. Conculsion: Astrocytoma was the most common pediatric brain tumor. Medulloblastoma was more common in males while pilocytic astrocytoma was more frequent in females. Posterior cranial fossa was the most common site (43.5%) of pediatric brain tumors. Low grade astrocytoma was more prevalent in posterior cranial fossa as compared to high grade astrocytoma which was more frequent in the supratentorial region
Clinico-morphological pattern and frequency of bone cancer
Objective:
The present study was done to find out the frequency of malignant tumors of bone and to categorize the prevelence of various histological types of osseous malignancies with respect to age, sex and site of origin.
Setting:
This study included consecutive cases of malignant bone tumors, which were diagnosed in the department of pathology at the Aga Khan University Hospital, Karachi during the period of three years (1995-1997).
Methods:
These tumors were initially evaluated on H & E stained section from paraffin embedded tissue blocks. Special stains and immunohistochemical analysis was performed whenever required.
Results:
A total of 169 malignant bone tumors were diagnosed during the study period. Metastatic tumors accounted for 28.4% of all malignant tumors of bone. Osteogenic sarcoma (27.2%) was the most frequent primary tumor of bone followed by Ewing’s sarcoma (12.4%), Non- Hodgkin’s lymphoma (10.6%), Chondrosarcoma (8.3%), Plasma Cell Myeloma (8.3%) and other rare entities (4.8%) in order of frequency.
Conclusion:
The most common malignant neoplasm diagnosed in osseous biopsies was metastatic tumors. Osteogenic sarcoma was the most frequent primary bone tumor in this series. The bone tumors were relatively more prevalent in males. The frequency of malignant bone tumor was relatively high as compared to developed countries
Clinicopathological profile of Wilms tumor
The profile of renal tumors in children less than 15 years of age during the period 1991-1997 is presented. Among the 37 children with kidney tumors, 29 (78.4%) had Wilms\u27 tumor. There was also a 20-year-old female with Wilms\u27 tumor. The median age at presentation was 2.6 years (range 2.5 months to 20 years). 66.7% of the cases diagnosed were \u3c or = 3 years and 90% were \u3c or = 6 years. Five cases were under one year of age. The male to female ratio was 2:1. Twenty-two cases (73.3%) were triphasic and 7 (23.3%) were biphasic. Only one case was monophasic with blastemal component. Five cases (16.7%) showed nephrogenic rests in the uninvolved renal parenchyma and one case had nephroblastomatosis. The tumor was favorable in 26 cases (86.7%) and unfavorable in 4. Fourteen cases were in-patients while 16 were outside referrals. The pathological (10 cases whose specimens were sent from other centers) and clinicopathological (13 hospitalized patients) staging showed 10 cases (43.5%) with stage 1, 4 cases (17.4%) with stage 2, and 7 cases (30.4%) with stage 3. In two cases (8.7%), there was stage 4 disease. The length of the follow-up period in the 13 hospitalized patients ranged from 7 days to 5 years 5 months (median 14 months). There was one recurrence and one death after 2 years of diagnosis
Immunohistochemical evaluation of small round cell tumors of childhood
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 (\u3c15 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