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Biomedical subjects

R Pathmanathan

Publications and source records attributed to R Pathmanathan.

At least 19 recordsLinked to original sources
PubMed2003

Ovarian sex cord-stromal tumors in children and adolescents.

PURPOSE: To develop diagnostic standards and a risk-adapted therapeutic strategy for ovarian sex cord-stromal tumors (OSCST). PATIENTS AND METHODS: Fifty-four patients were prospectively enrolled as follow-up patients onto the German Maligne Keimzelltumoren protocols. Surgical protocols and histopathology were reviewed centrally (53 patients with complete data). Surgery included ovariectomy in 18 patients, salpingo-ovariectomy in 34 patients, and hysterectomy in one patient. Patients with stage IA tumors were followed-up at regular intervals, whereas nine patients with stage IC and six patients with stage II to III tumors were treated with cisplatin-based chemotherapy. RESULTS: International Federation of Gynecology and Obstetrics stage was IA in 27 patients, IC in 21 patients, II in three patients, and III in three patients. After a median follow-up of 59 months (range, 6 to 193 months), event-free survival +/- SD was 0.86 +/- 0.05 (47 of 54 patients) and overall survival was 0.89 +/- 0.05 (49 of 54 patients). Prognosis correlated with stage (event-free survival +/- SD: IA, 1.0 [27 of 27 patients]; IC, 0.76 +/- 0.09 [16 of 21 patients]; and II/III, 0.67 +/- 0.19 [four of six patients]; P =.02). Ten of 15 patients treated with chemotherapy, including four of six stage II to III patients, are alive after a median follow-up of 33 months. CONCLUSION: On the basis of a standardized clinical and histopathologic assessment, risk-adapted therapeutic strategies for OSCST can be evaluated. Considering our experience, we would recommend that stage IA tumors be followed up at regular intervals, whereas we would recommend cisplatin-based chemotherapy in stage IC tumors with preoperative rupture or malignant ascites, especially those with high mitotic activity. Finally, cisplatin-based chemotherapy also seems to be effective in advanced-stage tumors.

Adolescent↗
PubMed1999

The impact of teleradiology in clinical practice--a Malaysian perspective.

Teleradiology is the most mature and rapidly evolving specialty in telemedicine. The use of teleradiology has grown tremendously during the past few years. This article describes the role of teleradiology in health care along with a brief history of its development in tandem with advances in telecommunications and computer technologies. Teleradiology standards, image acquisition, data compression, transmission and image interpretation are summarised. The impact of teleradiology in the practice of radiology, traces the evolution of the modality especially in the Malaysian perspective and its current and future role are discussed.

Delivery of Health Care↗
PubMed1997

Trans (elaidic) fatty acids adversely affect the lipoprotein profile relative to specific saturated fatty acids in humans.

Although dietary trans fatty acids can affect plasma lipoproteins negatively in humans, no direct comparison with specific saturated fatty acids has been reported, even though trans fatty acids were designed to replace saturates in foods and food processing. In this study, dietary trans 18:1 [elaidic acid at 5.5% energy (en)] was specifically exchanged for cis 18:1, 16:0 or 12:0 + 14:0 in 27 male and female subjects consuming moderate fat (31% en), low cholesterol (<225 mg/d) whole food diets during 4-wk diet periods in a crossover design. The trans-rich fat significantly elevated total cholesterol and LDL cholesterol relative to the 16:0-rich and 18:1-rich fats and uniquely depressed HDL cholesterol relative to all of the fats tested. Trans fatty acids also elevated lipoprotein (a) [Lp(a)] values relative to all dietary treatments. Furthermore, identical effects on lipoproteins were elicited by 16:0 and cis 18:1 in these subjects. The current results suggest that elaidic acid, one of the principal trans isomers produced during industrial hydrogenation of edible oils, adversely affects plasma lipoproteins. Thus, the negative effect of elaidic acid on the lipoprotein profile of humans appears to be unmatched by any other natural fatty acid(s).

Adult↗
PubMed1997

Gastric strongyloidiasis in a Malaysian patient.

Strongyloides stercoralis infection is of low prevalence in Malaysia. We report an unusual case presenting primarily with gastric symptoms. The patient was a 72 years old Chinese male admitted for progressive weight loss and abdominal bloating. Gastroscopic examination revealed mucosal prepyloric elevations in the gastric mucosa. Gastric strongyloidiasis was confirmed by the presence of adult forms, as well as ova and larval rhabditiform stages of the worm in the gastric mucosal crypts. We believe that this is the first histologically documented case of gastric strongyloidiasis in Malaysia.

Aged↗
PubMed1996

Human infection with Dirofilaria repens in Malaysia.

Human dirofilariasis is a rare infection in Malaysia. Thus far, only two human cases have been reported viz. Dirofilaria immitis and D. (Nochtiella) repens and in both instances, adult worms were recovered from infected patients. The two cases reported in the present study, one from Melaka and the other from Penang, were diagnosed histologically. Based on the diagnostic criteria for identifying Dirofilaria in tissue sections, the parasites were identified as D. (Nochtiella) repens.

Adult↗
PubMed1996

True hermaphrodite--a case report.

A case report of a male true hermaphrodite with 46XX/46XY karyotype is presented. He was first diagnosed at the age of 9 years when he presented with hypospadias and a left undescended testis. He was lost to follow-up until he presented at the age of 23 years with bilateral gynaecomastia. A hormonal profile showed a low testosterone level, while a seminal assay showed very few sperms. However he claimed to be sexually active. A year later, after he got married, he began to complain of impotence. A review of the condition is presented.

Adult↗
PubMed1995

Clonal proliferations of cells infected with Epstein-Barr virus in preinvasive lesions related to nasopharyngeal carcinoma.

BACKGROUND: The Epstein-Barr virus (EBV) is consistently detected in patients with nasopharyngeal carcinoma. To determine whether EBV infection is an early, initiating event in the development of this malignant tumor, we screened nasopharyngeal-biopsy samples, most of which were archival, for preinvasive lesions, including dysplasia and carcinoma in situ. Preinvasive lesions were found in 11 samples, which were tested for the presence of EBV. METHODS: EBV infection was detected with in situ hybridization for EBV-encoded RNAs (EBERs) and by immunohistochemical staining for latent membrane protein 1 (LMP-1). The larger samples were also tested for the EBV genome with the use of Southern blotting. The expression of specific EBV RNAs was determined by the amplification of complementary DNA with the polymerase chain reaction. RESULTS: Evidence of EBV infection was detected in all 11 tissue samples with dysplasia or carcinoma in situ. EBERs were identified in all eight samples tested, and LMP-1 was detected in all six of the tested samples. Six of the seven samples tested for the EBV termini contained clonal EBV DNA: Transcription of the latent EBV gene products, EBV nuclear antigen 1, LMP-1, LMP-2A, and the BamHI-A fragment, was detected in most of the samples. Viral proteins characteristic of lytic lesions were not detected. CONCLUSIONS: Preinvasive lesions of the nasopharynx are infected with EBV. The EBV DNA is clonal, indicating that the lesions represent a focal cellular growth that arose from a single EBV-infected cell and that EBV infection is an early, possibly initiating event in the development of nasopharyngeal carcinoma. Preinvasive lesions contain EBV RNAs that are characteristic of latent infection but not the viral proteins that are characteristic of lytic infection. The detection of the EBV-transforming gene, LMP-1, in all the neoplastic cells suggests that its expression is essential for preinvasive epithelial proliferations associated with nasopharyngeal carcinoma.

Antigens, Viral↗
PubMed1995

Clonorchiasis/opisthorchiasis in Malaysians case reports and review.

Clonorchiasis and opisthorchiasis are snail-transmitted trematode infections. The disease is endemic in many parts of Asia. Local case reports have been predominantly in Chinese with a history of travel to endemic countries. Thus far, 20 cases of liver fluke infestation have been reported in this country. This report presents another two cases of clonorchiasis and a case of opisthorchiasis. We also briefly review pertinent aspects of the disease.

Animals↗
PubMed1995

Retroperitoneal malignant fibrous histiocytoma with renal involvement.

Malignant fibrous histiocytoma is a mesenchymal tumour which can involve the genitourinary organs primarily or by secondary extension. Both conditions are rare. We report four cases of retroperitoneal malignant fibrous histiocytoma involving the kidney by local extension. Diagnosis was difficult because of diverse, non-specific clinical features and may only be reached at operation or post mortem. Prognosis is poor. Although en bloc tumour resection with nephrectomy was possible in two patients, they returned with recurrences.

Adult↗
PubMed1995

Undifferentiated, nonkeratinizing, and squamous cell carcinoma of the nasopharynx. Variants of Epstein-Barr virus-infected neoplasia.

Nasopharyngeal carcinoma (NPC) samples of distinct histological types, including squamous cell carcinoma (WHO type 1), nonkeratinizing carcinoma (WHO type 2), and undifferentiated carcinoma (WHO type 3), were analyzed for Epstein-Barr virus (EBV) infection and gene expression by using in situ and biochemical techniques. The EBV-encoded RNAs (EBER) were detected in situ in most tumor cells of all three WHO types of NPC. In foci of squamous differentiation and keratinization within less differentiated NPC and throughout the expanse of well differentiated squamous cell carcinoma, EBER expression was less abundant. Latent membrane protein, an EBV-encoded membrane protein, was detected in 72% (36/50) of all NPC and 67% (6/9) of the cases of squamous cell carcinoma. The EBV genomes were present as clonal episomal forms, without detectable linear viral DNA, in all cases of squamous cell carcinoma analyzed. Polymerase chain reaction amplification of cDNA detected EBV transcription for Epstein-Barr nuclear antigen 1, latent membrane proteins 1 and 2, and BamHI A in all samples, indicating that all forms of NPC express the same EBV genes. These results reveal that EBER expression is significantly decreased in areas with squamous differentiation and confirm that all types of NPC, regardless of histological type or differentiation contain clonal episomal EBV genomes, express specific EBV genes and are a clonal expansion of EBV-infected cells.

Base Sequence↗
PubMed1994

Light microscopic and three-dimensional morphology of the human muscular sarcocyst.

Established criteria for morphological typing of sarcocysts was applied to a large series of cases of human skeletal muscle sarcocystosis in Malaysia to determine the type of sarcocyst present. We also wanted to test the general usefulness of this classification and to determine if there are any new cyst types. Three-dimensional (3-D) reconstruction was done to see if the sarcocyst has a distinct 3-D morphology. A total of 66 sarcocysts from 21 cases of human muscle sarcocystosis obtained from a previous prevalence study were examined. Tissue sections (5 microns thick) were stained with haematoxylin and eosin and studied under the light microscope. For 3-D reconstruction, an image analyser was used to align and reconstruct the sarcocyst after microscopic images had been captured with a charge-coupled device (CCD) camera. All the cysts best fit into the type 4 category. This classification is generally useful, although cyst wall characteristics and zoite size appear to be the most reliable criteria for classification. The cyst width averaged 77 microns (range, 30-137.5 microns). Cyst walls were smooth, had no cytophaneres and were less than 1 micron thick. No secondary cyst wall or surrounding inflammation was evident. Numerous cyst merozoites with diameters averaging 1 micron filled the cyst lumen. Although septa were not apparent, in many cysts, zoites were arranged in a unique, curvilinear fashion that suggested their presence. 3-D reconstruction showed the sarcocyst to be a long, tortuous "cylinder" with no branching or other distinguishing feature.

Animals↗
PubMed1994

Ultrastructure of the human skeletal muscle sarcocyst.

The ultrastructure of the human skeletal muscle sarcocyst found in Malaysia is reported. Sarcocyst-positive, formalin-fixed tongue tissues were postfixed in osmium tetroxide. The primary cyst wall consisted of a thin membrane supported by osmiophilic material that was interrupted regularly by vesicle-like invaginations. Although there were no cytophaneres, stubby protrusions of the primary wall were observed. These protrusions were accentuated by dense, curvilinear material externally. The primary wall was wavy over about half the cross section of the cyst. The granular ground substance underlying the primary wall occasionally contained hitherto undescribed coiled microtubular structures. Branching septa extended from the ground substance into the cyst, separating mature merozoites into compartments. A few peripheral metrocytes and many laminated myelin figure-like structures, probably degenerating merozoites, were found. Although the human muscular sarcocyst has the same basic ultrastructure as those found in other animals, the stubby protrusions and coiled microtubular structures in the ground substance have not been described previously in nonhuman animals.

Animals↗
PubMed1993

Elevated secretory IgA antibodies to Epstein-Barr virus (EBV) and presence of EBV DNA and EBV receptors in patients with cervical carcinoma.

Epstein-Barr virus (EBV) receptors (EBV/C3d receptors) were detected, using the monoclonal antibody HB5, on 23 ectocervical and 5 endocervical biopsies of the uterine cervix. Elevated IgA titers against the viral capsid antigen and early antigen of EBV were also found in the cervical secretions from cervical carcinoma patients (83%), compared with samples from patients with cervical intraepithelial neoplasia (75%), herpes simplex virus-infected patients (0%), and gynecologic patients with nonmalignant conditions (0%). EBV DNA was present in 63% of cervical carcinoma biopsies detected by in situ hybridization. These observations suggest a positive association between EBV and carcinoma of the cervix.

Analysis of Variance↗