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F C Ho

Publications and source records attributed to F C Ho.

At least 55 records · Page 3Linked to original sources
PubMed1993

Pattern of cerebral atherosclerosis in Hong Kong Chinese. Severity in intracranial and extracranial vessels.

BACKGROUND AND PURPOSE: The clinical pattern of stroke and the angiographic distribution of cerebral atherosclerosis in Chinese are different from those in Caucasians. Pathological data from autopsy studies are lacking. METHODS: The intracranial and extracranial arteries supplying the brains of 114 consecutive Chinese patients undergoing autopsy in a regional general hospital were examined by computer-assisted morphometric analysis under a microscope as well as by macroscopic grading for atherosclerotic narrowing. The severity was correlated with various atherosclerosis-related factors. RESULTS: Atherosclerosis of the intracranial cerebral vessels was more severe than that of the extracranial vessels. The distal branches of the intracranial vessels were also commonly involved. Hypertension and diabetes mellitus were identified as factors associated only with intracranial atherosclerosis (p < 0.001), whereas ischemic heart disease was associated with atherosclerosis in both the intracranial (p < 0.001) and extracranial (p = 0.012) vessels. Smoking was associated with narrowing of the extracranial vessels only (p = 0.0054). CONCLUSIONS: Compared with figures from Caucasian and Japanese populations, the extent of intracranial atherosclerosis is much more severe in Hong Kong Chinese, whereas atherosclerotic narrowing of the extracranial carotid artery is less severe in Hong Kong Chinese than in Caucasians.

Adolescent↗
PubMed1993

CEA tissue staining in colorectal cancer patients--correlation with plasma CEA, histology and staging.

To study the expression of tissue carcinoembryonic antigen (CEA) by immunoperoxidase staining in colorectal adenocarcinomas and its relation with preoperative serum CEA and clinicopathological parameters, we studied 85 unselected patients who underwent resective surgery for colorectal adenocarcinomas and were followed up for a mean of 66 mths. All tumors except 2 showed positive staining for CEA. The staining pattern was classifiable into 4 types: apical, cytoplasmic, basolateral and stromal, according to the predominant sites of staining. We found a significant positive correlation between tissue CEA staining pattern and preoperative plasma CEA. Plasma CEA levels were higher when tumor cell staining extended to basolateral regions of the cells and into stromal tissues rather than restricted to apical and cytoplasmic regions (p = 0.012). Furthermore, tissue CEA staining also correlated positively with vascular invasion by tumor cells (p = 0.046), with basolateral and stromal types associated with more frequent vascular invasion than apical and cytoplasmic types. This was in contrast to the preoperative CEA which did not correlate with vascular permeation. We speculate that tissue CEA staining is useful in indicating possible vascular invasion even at early stage whereas vascular invasion by a larger tumor bulk or even tumor metastases may be necessary to produce an increased plasma CEA level that is detectable. On the other hand, preoperative plasma CEA had a strong, positive relationship with tumor stage and mortality (p < 0.001 for both). Preoperative CEA was higher in tumors showing moderate and poor differentiation, although it did not reach statistical significance (p = 0.068), whereas tissue CEA staining had no correlation with tumor differention.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma↗
PubMed1992

Deletions, duplications and novel restriction fragment length polymorphism in Duchenne and Becker muscular dystrophies.

To determine the mutations of Southern Chinese with Duchenne and Becker muscular dystrophies (DMD, BMD), we analysed 28 DMD and BMD patients in 24 unrelated families for intragenic deletions and duplications by using cDNA probes covering the entire 14 kb of the dystrophin gene. Deletions were detected in nine unrelated patients (seven patients by probe 8 and two by probe 2b-3). Gene duplications were detected by probe 1-2a in two patients with the duplication bands confirmed in both Hind III and Bgl II digests and by densitometry. A third patient was found to have a junction fragment with Bgl II and a duplication band with Hind III by probe 5b-7. Therefore 50% of the 24 unrelated families were found to have either deletions or duplications. A previously undescribed restriction fragment length polymorphism (RFLP) was found in one family with probe 5b-7 in Bgl II digests which was found to segregate with the disease phenotype. This new RFLP was not detected in over 70 unrelated X chromosomes we have examined so far, and appeared to be "private" for this family. The presence of this new restriction site may or may not be the mutation responsible for the disease phenotype.

Asian People↗
PubMed1992

Antinuclear antibody detection using streptavidin-biotin-peroxidase complex on HEp-2 cell substrate.

The streptavidin-biotin-peroxidase complex (SABC) technique was compared to conventional indirect immunofluorescence (IIF) for the detection of anti-nuclear antibody (ANA) on HEp-2 cell substrate. SABC showed higher specificity and predictive value and gave more reproducible titres and clearer staining patterns than IIF in sera from a series of rheumatic disease patients. Sera from 80 patients with various types of rheumatic diseases and 20 without rheumatic disease were further tested using the SABC method. All systemic lupus erythematosus (SLE) sera were positive. The overall sensitivity was 95%, specificity 90% and predictive value 97% for rheumatic disease. The rim pattern was associated with SLE and mixed connective tissue disease. The nucleolar/homogeneous pattern was associated with scleroderma and SLE in remission. ANA titre and staining pattern have limited value in the clinical assessment of rheumatic disease; however, ANA has very high sensitivity for SLE and remains an excellent screening test.

Antibodies, Antinuclear↗
PubMed1991

Intensive chemotherapy for adult lymphoblastic lymphomas.

A total of 20 adults patients presenting with previously untreated lymphoblastic lymphoma underwent an intensive chemotherapy protocol. Either the BACOP or the m-BACOD regimen was used for induction. If the patients achieved a complete clinical remission (CR) after three courses, they were given intensive consolidation and maintenance chemotherapy based on a protocol that was modified from the L10/L17M regimen of the Memorial Sloan-Kettering group for acute lymphoblastic leukaemia and lymphoblastic lymphoma. Patients exhibiting localised areas of bulky disease were given additional involved-field radiotherapy. In all, 15 (75%) men and 5 (25%) women were entered in this study. Their median age was 28 years (mean, 30 years; range, 12-64 years). Overall, 3 (15%) had stage II disease, 3 (15%) had stage III disease and 14 (70%) had stage IV disease; 7 (35%) patients exhibited B symptoms and 4 (20%) had bulky disease. The overall (CR) rate was 10/20 (20%), and that following BACOP and m-BACOD therapy was 4/8 (50%) and 6/12 (50%), respectively. In all, 7 of the 10 complete responders (70%) relapsed. The disease-free survival of the ten who achieved a CR was 23% at 3 years. The overall survival of all 20 patients at 3 years was only 37%, and there were very few long-term survivors. More effective treatment for adult lymphoblastic lymphoma is required.

Adult↗
PubMed1990

Nasal lymphoma. A retrospective analysis of 60 cases.

Sixty cases of nasal lymphomas were reviewed. There were 42 men and 18 women. The median age was 49 years. The histologic types were low grade in four cases, intermediate grade in 33, high grade in seven, and unclassifiable in 16. Thirteen cases had features of polymorphic reticulosis. The immunophenotype was available in 18 cases and a majority of 67% of them were T-cell. Forty-one of them (68%) had clinically localized (Stage I and II) disease which often spread locally to neighboring tissues and they presented predominantly with nasal symptoms. Nasal lymphoma appeared to carry a poor prognosis. Although our patients with clinically localized disease had significantly better prognosis than those with advanced disease, the 5-year survival of Stage I and II patients was only 55%. Chemotherapy did not appear to be more effective than radiotherapy alone in preventing relapses but the patient number was too small to allow a firm conclusion to be made. Patients with advanced disease had even poorer prognosis with a 5-year survival of only 17%. Innovative therapy has to be developed for these patients.

Adolescent↗
PubMed1990

Histologic subtypes and survival of Chinese patients with non-Hodgkin's lymphomas.

The histologic subtypes and survival of 840 Chinese patients with non-Hodgkin's lymphoma (NHL) were reviewed. All cases were classified according to the Rappaport and Kiel systems and the Working Formulation (WF). A low incidence of nodular/follicular lymphomas (12%) was observed. The most common histologic subtypes were diffuse histiocytic, diffuse centroblastic, and diffuse large cell lymphomas, according to Rappaport, Kiel, and the WF, respectively. A high proportion (24%) of the cases were unclassifiable, according to Kiel, because of the precise terms of the classification. The "favorable"-prognosis NHL, according to Rappaport, or the low-grade NHL, according to Kiel and the WF, had a more indolent clinical course. However, except for the nodular mixed (Rappaport) or follicular mixed (WF) lymphomas which appeared to behave like the more aggressive NHL, a plateau was not seen in the survival curves of our patients with other kinds of favorable-prognosis or low-grade NHL, indicating the lack of curative potential of these tumors. The lymphoplasmacytoid lymphoma, according to Kiel, also appeared to have a more aggressive clinical course. A plateau was seen in most of the other survival curves of patients with the more aggressive tumors, indicating the prospect of cure. However, the prognosis of the very aggressive tumors such as the diffuse lymphoblastic and diffuse small noncleaved cell lymphomas, according to the WF, remains very poor with a median survival of less than 10 months.

Adolescent↗
PubMed1990

Polymorphic reticulosis and conventional lymphomas of the nose and upper aerodigestive tract: a clinicopathologic study of 70 cases, and immunophenotypic studies of 16 cases.

Seventy patients with malignant lymphomas, including the entity known as polymorphic reticulosis (PR), involving the nose, nasal sinuses, nasopharynx, oropharynx (excluding tonsil), and larynx were studied. There were 26 cases of PR, 19 cases of lymphoma with features of PR (ML[PR]) and 25 cases of conventional lymphomas. Fourteen of the 25 conventional lymphomas were due to dissemination from distant sites. For all histologic types of primary lymphoma, the presenting symptoms were similar, and the nasal cavity was more commonly involved than the nasopharynx. Patients with PR were younger, had a higher male:female ratio, and had a better overall survival rate than patients with conventional lymphomas. Cryostat section immunohistochemistry performed on 17 samples from 16 patients showed only one B lymphoma out of 11 primary lesions; the other 10 cases and three recurrent tumors at distant sites showed phenotypic markers of T lymphocytes and natural killer cells. All three secondary tumors were of B-cell type. Of eight patients with sequential biopsies, progression to a more malignant histopathologic type was found in six. In the PR and ML[PR] biopsies, angiocentricity was detected in 11%, and angioinvasion in 22%. We could not confirm identity of PR with other angiocentric immunoproliferative lesions.

Humans↗
PubMed1990

Translocation of bcl-2 gene in non-Hodgkin's lymphomas in Hong Kong Chinese.

The close association between translocation of the proto-oncogene bcl-2 and follicular lymphomas has been well established in Caucasian patients and the de-regulation of bcl-2 has been implicated in follicular lymphomagenesis. Similar molecular structural alterations have also been detected in diffuse lymphomas with a previous history of a follicular pattern as well as in a smaller proportion of de novo diffuse lymphomas. There is a lower incidence of follicular lymphomas in Chinese. In order to investigate further this phenomenon, we used bcl-2 translocation as a genetic marker of follicular lymphomas, to study 31 cases of B cell non-Hodgkin's lymphomas in Chinese patients by Southern blot analysis. Eight out of 16 cases of follicular lymphomas showed bcl-2 translocation with involvement of the major breakpoint region (MBR). Six of these cases utilized breakpoints within the 4.3 kb HindIII fragment, while in two cases the breakpoints were more dispersed, but still within the BamHI fragment. An additional case of follicular lymphoma showed translocation of bcl-2 gene with involvement of the minor cluster region (mcr), making a total of nine out of 16. None of the 15 cases of diffuse lymphomas showed similar molecular structural alterations. These data show that bcl-2 translocation is present in 57% of follicular lymphomas in Chinese patients, and support the notion that bcl-2 translocation is a consistent marker for follicular lymphomas irrespective of ethnic differences. As the translocation is not detected in the diffuse lymphomas, there is no evidence to suggest that the low incidence of follicular lymphomas in Chinese patients is due to a greater tendency for follicular tumours to progress rapidly and present as diffuse lymphomas.

Blotting, Southern↗
PubMed1989

Central nervous system involvement in non-Hodgkin's lymphoma.

Fifty-eight Hong Kong Chinese patients with CNS lymphoma were reviewed (primary seven, secondary 51). The incidence of secondary CNS lymphoma in patients with non-Hodgkin's lymphoma was estimated to be 9.4%. The Working Formulation separated subtypes which had a special propensity to involve the CNS. Significant proportions of our patients with secondary CNS lymphoma had other features which were known to be associated with a high risk of CNS disease including stage IV (48/51, 91.4%), bone marrow (26/51, 50.9%), peripheral blood (7.51, 13.7%), nasal (7/51, 13.7%), orbital (3/51, 5.9%), testicular (2/51, 3.9%) and bulky retroperitoneal (6/51, 11.8%) disease. 82% of patients with secondary CNS lymphoma had concurrent systemic disease and a further 12% had systemic relapse shortly afterward. CNS lymphoma is associated with poor prognosis and only 29% and 14% of the patients with primary and secondary CNS lymphoma respectively survived beyond 1 year. Patients responding to therapy had significantly better survival. 69.9% of the deaths were related to progressive systemic disease.

Adolescent↗
PubMed1989

Acute lymphoblastic leukemia in Chinese adults in Hong Kong.

Forty-four previously untreated Chinese adult patients with acute lymphoblastic leukemia (ALL) were treated with vincristine, adriamycin and prednisone with or without L-asparaginase. The clinical features and prognostic factors were similar to those reported in Caucasian series. Overall complete remission (CR) rate was 52%. Duration of first remission and overall median survival were nine and 12 months respectively. The addition of L-asparaginase did not improve CR rate or duration of remission and was associated with clotting dysfunction and other adverse reactions. Factors associated with a higher CR rate include age less than 40 years, blast count less than 10 x 10(9)/l and CALLA + phenotype at presentation. Sex, platelet count and FAB morphology did not affect CR rate. Bone marrow relapse occurred in 11 patients and was associated with short survival after relapse (median two months; mean two months; range 0.5-7 months). Central nervous system relapse occurred in four patients and was compatible with relatively long survival after relapse (median 13 months; mean 12 months; range 6-12 + months). The poor CR rate and short median survival in this study could not be adequately explained by an increase in risk factors and is likely to be due to what is currently regarded as suboptimal chemotherapy.

Adolescent↗
PubMed1988

Age-related changes in the morphology and immunophenotype of spontaneous lymphomas of SJL/N mice.

Forty-four SJL mice were killed at intervals to follow the spontaneous development of lymphomas. These were detected in 28 of 38 mice aged 24 weeks or more. Immunoperoxidase stains were applied on cryostat sections of lymphomas from various sites (spleen, mesenteric lymph nodes, Peyer's patches, and other lymph nodes), sampled from 19 mice of different age groups, to study tumour immunophenotype in correlation with histological features. With a panel of antibodies against Thy 1.2, Lyt 1, and Lyt 2, and the mouse immunoglobulin heavy and light chains, all the 19 tumours were shown to be B-cell derived. This was further supported by the detection of Ia antigens on the tumour cells. Six mice had plasmacytoid or predominantly plasmacytoid tumours expressing gamma kappa. Three mice had mixed plasmacytoid and pleomorphic tumours which also showed gamma kappa positivity. The ages of these nine mice ranged from 24 to 44 weeks with a median of 36 weeks. Pleomorphic tumours were found in ten mice (age range = 36-52 weeks, median = 44 weeks). These tumours were more heterogeneous, expressing either alpha, mu, or gamma, or with loss of heavy chain expression altogether. These age-related changes are probably a sign of progressive loss of differentiation in B lymphomas.

Aging↗
PubMed1987

Adult Fanconi syndrome in kappa light chain myeloma.

Distinctive morphological features in both the marrow infiltrate and the kidney were seen in a 52-year-old woman with kappa light chain-producing plasma cell myeloma, diagnosed on the basis of multiple osteolytic lesions, the presence of atypical plasma cells in the bone marrow, and monoclonal immunoglobulin production as demonstrated by immunoperoxidase staining on marrow sections. Large focal collections of histiocytes in the bone marrow and the renal proximal tubular epithelium had abundant glassy cytoplasm. Characteristic crystalline inclusions were seen ultrastructurally in both types of cells. It is believed that these crystalline deposits are lysosomal inclusions composed of altered kappa light chains taken up by these cells. The renal changes were entirely different from those of myeloma kidneys and were associated with proximal tubular dysfunction of adult Fanconi syndrome without distal tubule abnormality.

Biopsy↗
PubMed1987

A new model of AA-amyloidosis induced by oral pristane in BALB/c mice.

Fifteen male BALB/c mice were given six intermittent oral doses of O.I. ml pristane (2, 6, 10, 14 tetramethylpentadecane) within a period of 9 weeks. Fifteen mice receiving tap water using the same schedule formed the control group. Amyloidosis was first detected in the spleen of a mouse which had died 33 weeks after the first dose and 24 weeks after the last. All six mice which were subsequently autopsied 34-51 weeks after the first dose also showed amyloidosis involving liver and spleen. The most extensive tissue deposits were seen at 37-38 weeks whereas the older mice showed predominantly chronic renal lesions with papillary necrosis, scars and cystic change. Electron microscopy confirmed the identity of the amyloid fibrils and the presence of globular stellate amyloid 'bodies' in liver and spleen. The amyloid deposits were shown to be made up of AA (amyloid associated) protein using an indirect immunoperoxidase method and a monoclonal rat anti-murine AA protein antibody. We did not find any plasmacytomas or increased numbers of plasma cells in the bone marrow. None of the control mice developed amyloidosis. This new experimental model promises to provide a means of studying several aspects of secondary amyloidosis which may be relevant to the clinical situation.

Administration, Oral↗
PubMed1986

Immunohistological subtypes of non-Hodgkin's lymphoma in Hong Kong Chinese.

One hundred and four unselected cases of non-Hodgkin's lymphoma (NHL) in adult Chinese patients in Hong Kong were typed, using monoclonal and conventional antibodies, by immunoenzymatic labelling methods on cryostat sections or cell smears. The total included 69 cases (66%) of B-cell and 26 (25%) of T-cell tumours. The diffuse large cell (centroblastic or immunoblastic) types formed the largest proportion (44.9%) of B lymphomas. Of 26 cases of T-cell lymphoma 25 were of peripheral type; of these 25, the most frequent subtype (42.3%) was the immunoblastic lymphadenopathy-like lesion. Although there were 9 pleomorphic T-cell lymphomas, none of the patients presented with the adult T-cell leukemia/lymphoma syndrome. The incidence of T-cell lymphomas in our population is not markedly higher than that of western countries, but there are some interesting differences in the types of T-cell lymphomas that are commonly seen.

Adult↗
PubMed1985

Primary hypothyroidism and essential hypernatremia in a patient with histiocytosis X.

A 27 year old woman with histiocytosis X had an unusual initial presentation with features of primary hypothyroidism and a goitre. Diagnosis was made by lung and thyroid biopsies. Endocrine tests showed the presence of hypopituitarism and a discrete suprasellar mass, consistent with hypothalamic histiocytosis X, was demonstrated by computerised tomography. Radiotherapy and chemotherapy arrested the clinical progression of the disease.

Adult↗