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Biomedical subjects

S R Shi

Publications and source records attributed to S R Shi.

At least 37 records · Page 2Linked to original sources

Strategies for improving the immunohistochemical staining of various intranuclear prognostic markers in formalin-paraffin sections: androgen receptor, estrogen receptor, progesterone receptor, p53 protein, proliferating cell nuclear antigen, and Ki-67 antigen revealed by antigen retrieval techniques.

Different variations of the antigen retrieval technique using different retrieval solutions have been evaluated for their effectiveness in restoring the antigenicity of six intranuclear antigens, each of which is a potentially valuable prognostic indicator in formalin-fixed, paraffin-embedded tissue sections. The results of immunohistochemical staining for estrogen receptor, progesterone receptor, androgen receptor, p53 protein, proliferating cell nuclear antigen, and Ki-67 antigen were compared following the different antigen retrieval approaches. The strongest immunostaining signal with the clearest background was obtained by microwave heating of dewaxed paraffin sections for 10 minutes in 0.05 mol/L glycine HCl (pH 3.5) or in citrate buffer solution (pH 6). Urea solution, distilled water, and lead thiocyanate solution yielded improvements with some antigens, but less consistently and less impressively than glycine HCl buffer or citrate buffer. Following antigen retrieval nuclear staining was sharply defined and could be achieved consistently in a variety of tissues after formalin fixation for as long as 7 days. The duration of fixation, however, was an important variable; generally, the longer the fixation time the more vigorous the retrieval procedure required. This study demonstrates the ability to stain a variety of intranuclear antigens, which are not readily demonstrable otherwise, in formalin-paraffin sections with a high degree of consistency and reproducibility. The availability of methods that are effective in paraffin sections may facilitate studies of the possible value of these markers as prognostic indicators for predicting the response of major tumors to different forms of therapy. This study also provided insight into the basic principles of the antigen retrieval method, which may be helpful in attempts to develop a more uniformly standardized technique applicable to many different antigen systems.

Antigens, Neoplasm↗

Antigen retrieval using pH 3.5 glycine-HCl buffer or urea solution for immunohistochemical localization of Ki-67.

A new antibody (MIB-1) has been described, permitting the demonstration of Ki-67 proliferation antigen in paraffin sections. However, satisfactory results were obtained only after subjecting tissue sections to microwave based antigen retrieval in citrate buffer solution. Other buffer solutions produce equivalent or better results and also permit use of the original Ki-67 antibody, which hitherto has been considered ineffective for paraffin sections.

Buffers↗

Antigen retrieval technique utilizing citrate buffer or urea solution for immunohistochemical demonstration of androgen receptor in formalin-fixed paraffin sections.

We developed a staining protocol for demonstration of androgen receptor (AR) in formalin-fixed, paraffin-embedded tissue sections. The method is based on the antigen retrieval microwave (MW) heating technique. Results are compared with different types of enzyme digestion pre-treatments. The strongest immunostaining signal and clearest background were obtained by MW heating of dewaxed paraffin sections in 5% urea or citrate buffer solution (pH 6); pure distilled water gave less consistent results. Enzymatic digestion with pepsin (0.05% in 2 N HCl) for 30 min at room temperature, or trypsin followed by pronase, or pronase digestion alone, also produced enhanced staining of AR in some cases, but there was more nonspecific background, and specific reactivity was less intense. The antigen retrieval MW method can be used to demonstrate AR epitope in prostate tissue after fixation in formalin for as long as 7 days. AR immunolocalization was also compared in frozen and paraffin sections processed from the same specimen of prostate carcinoma tissue and was found to be qualitatively and quantitatively similar. This study also provided new information concerning the basic principles of the antigen retrieval MW method that may be helpful in further development of this technique.

Antigens, Neoplasm↗

Immunohistochemical study of intermediate filament proteins on routinely processed, celloidin-embedded human temporal bone sections by using a new technique for antigen retrieval.

Although immunohistochemical studies of intermediate filament proteins have been carried out on temporal bone sections by using modified fixation/embedding techniques to preserve antigenicity, there have been no light microscopic studies concerning immunohistochemical staining on routinely formalin-fixed celloidin-embedded human temporal bone sections. A method for immunostaining routinely processed celloidin-embedded tissues would be extremely valuable in that it would permit study of the extensive collections of formalin-celloidin temporal bone specimens that exist in major centers of otopathologic research. Recently, we have developed a new technique which can be used to retrieve the antigenicity masked by formalin fixation and decalcification. This method requires immersing slides for 30 min at room temperature in a solution of saturated sodium hydroxide in methanol before immunostaining. Using this method, 45 celloidin-embedded human temporal bone sections were stained with monoclonal antibodies to keratin, vimentin, neurofilament, glial fibrillary acidic protein and desmin as primary antibodies using a sensitive streptavidin-biotin procedure. The results obtained by using this technique are at least equivalent to those obtained with modified fixatives, cryosections or immuno-electron microscopy. This new method may provide a useful approach for studying routinely processed, celloidin-embedded human temporal bone sections and open a new field in immuno-otopathology.

Adult↗

A technique for retrieving antigens in formalin-fixed, routinely acid-decalcified, celloidin-embedded human temporal bone sections for immunohistochemistry.

The application of immunohistochemistry to routinely decalcified, celloidin-embedded human temporal bone sections has been hampered because of antigen loss during processing of the specimens. To our knowledge, there has been no published report to date describing immunohistochemical staining of such tissues suitable for examination by light microscopy. Here we report a novel antigen retrieval technique which can be successfully used to stain a variety of antigens in routinely formalin-fixed, trichloroacetic acid-decalcified, celloidin-embedded human temporal bone sections. The new procedure reported here for decalcified human temporal bone tissues simply requires immersing slides for 30 min at room temperature in an antigen retrieval solution. A total of 60 decalcified, celloidin-embedded human temporal bone tissues were tested with monoclonal antibodies (MAb) to 15 different antigens. Of these, 12 MAb showed definite positive staining, while three were negative. This technique may prove very useful in studying the expression of various antigens by immunohistochemistry in formalin-fixed, acid-decalcified, celloidin-embedded tissues.

Antibodies, Monoclonal↗

S-100 protein in human inner ear: use of a novel immunohistochemical technique on routinely processed, celloidin-embedded human temporal bone sections.

The authors recently developed a new antigen retrieval technique which allows immunohistochemical detection of proteins in routinely processed, celloidin-embedded human temporal bone sections. This technique was used in the present study, which reports the occurrence of S-100 protein in the human inner ear. Fifteen celloidin-embedded human temporal bone sections, obtained from the Eastern Temporal Bone Bank at the Massachusetts Eye and Ear Infirmary, were tested with the monoclonal antibody to S-100. This protein was found in the spiral ligament, in Reissner's membrane, in the spiral limbus, and in the basement membrane of the cochlea. S-100-positive, thin fibers could be seen as supporting elements in the acoustic nerve and the facial nerve. This protein was localized along the surface of vestibular wall. The new technique provides an immunohistochemical approach to studying routinely processed human temporal bone sections and may prove useful in the field of immuno-otopathology.

Collodion↗

Antigen retrieval in formalin-fixed, paraffin-embedded tissues: an enhancement method for immunohistochemical staining based on microwave oven heating of tissue sections.

We describe a new approach for retrieval of antigens from formalin-fixed, paraffin-embedded tissues and their subsequent staining by immunohistochemical techniques. This method of antigen retrieval is based on microwave heating of tissue sections attached to microscope slides to temperatures up to 100 degrees C in the presence of metal solutions. Among 52 monoclonal and polyclonal antibodies tested by this method, 39 antibodies demonstrated a significant increase in immunostaining, nine antibodies showed no change, and four antibodies showed reduced immunostaining. In particular, excellent immunostaining results were obtained with a monoclonal antibody to vimentin as well as several different keratin antibodies on routine formalin-fixed tissue sections after pre-treatment of the slides with this method. These results showed that after antigen retrieval: (a) enzyme predigestion of tissues could be omitted; (b) incubation times of primary antibodies could be significantly reduced, or dilutions of primary antibodies could be increased; (c) adequate staining could be achieved in long-term formalin-fixed tissues that failed to stain by conventional methods; and (d) certain antibodies which were typically unreactive with formalin-fixed tissues gave excellent staining.

Antibodies, Monoclonal↗

Immuno-electron microscopic study of keratin distribution in the cochlea using monoclonal antibody.

Keratin distribution in the cochlea has been studied immuno-electron microscopically by both pre-embedding and postembedding methods. Keratin immunoreactivity in the guinea pig cochlea was clearly demonstrated in Hensen's cells, the reticular lamina surrounding both outer and inner hair cells, outer and inner pillar cells, Claudius' cells, inner and external sulcus cells, interdental cells of the spiral limbus, Reissner's membrane, border cells, inner phalangeal cells, Deiters' cells, and spiral prominence cells. Keratin expression at the ultrastructural level showed a nonfilamentous keratin system in the cytoplasm of cochlear supporting cells.

Animals↗

Temporal bone findings in a case of otopalatodigital syndrome.

The principal features of the otopalatodigital syndrome are hearing loss, cleft palate, and skeletal dysplasia of the hands and feet. The right temporal bone was acquired from a boy with this syndrome who died at the age of 2 1/2 years. Behavioral audiometry had indicated a conductive hearing loss, with probable near-normal sensorineural function; brainstem evoked response audiometry indicated a mild sensorineural hearing loss. Histologic studies of the temporal bone revealed dysmorphic features in both the middle ear and the bony labyrinth. The ossicles were deformed, the stapes was fixed, and no round window was present. A defect of the modiolus resulted in a wide communication between the subarachnoid space of the internal auditory canal and the scala vestibuli. These anomalies would clearly have frustrated any attempt to improve the patient's hearing through reconstructive middle ear surgery.

Abnormalities, Multiple↗

Immunohistochemical localization of keratin in head and neck neoplasms and normal tissues.

Immunohistochemical localization of keratin antigens using keratin antisera and the immunoperoxidase technique have been shown to be helpful in identifying certain epithelial cells. Our study was designed to evaluate the application of this technique to head and neck neoplasms and normal tissues using two keratin antibody preparations. Our data indicate that the keratin antibodies stained normal epithelial structures in the head and neck except for cells with active secretory functions such as mucus, cerumen, or salivary secretion. Neoplasms of the head and neck showed keratin antibody staining for epithelial neoplasms and negative staining for mesenchymal neoplasms. The immunohistologic demonstration of keratin is useful in distinguishing undifferentiated or poorly differentiated epithelial malignancies from sarcomas or lymphomas and demonstrating myo-epithelial cells in salivary neoplasms.

Animals↗

Surgical pathology of middle ear implants.

During the past 15 years a series of 25 middle ear implants was removed at the time of revision surgery and prepared for histological study. These revision operations were performed because of failure to control the disease and/or persistent or recurring hearing loss. The ossicular and cortical bone autografts showed similar behavior in that they underwent creeping substitution with vitalized bone in amounts varying from 0% to 83%. There was no correlation to duration of implantation. The four cartilage grafts, on macroscopic evaluation, showed a loss of rigidity. Two of three cartilage autografts showed a high rate of survival of chondrocytes. The two TORP prostheses showed extensive invasion of their porous spaces with foreign body giant cells. One of the latter, implanted for over four years showed fibrous replacement of plastic material. The two polyethylene tubes showed intraluminal foreign body reaction and new bone formation.

Adolescent↗

Mixed olfactory neuroblastoma and carcinoma. A report of two cases.

Two cases of olfactory neuroblastoma mixed with other neoplastic elements are reported. One tumor contained foci of adenocarcinoma and of ganglioneuroblastoma in addition to an undifferentiated small cell component consistent with neuroblastoma; the other tumor histologically resembled small cell undifferentiated carcinoma with foci of squamous differentiation, but was shown by electron microscopy to be neuroblastoma. The histogenesis and treatment of mixed tumors of this type are discussed.

Adenocarcinoma↗

Keratin antibody localization in head and neck tissues and neoplasms.

Immunohistochemical staining for keratin proteins may be useful as a diagnostic parameter in head and neck neoplasms. Our study evaluates the keratin antibody staining properties of normal tissues as well as neoplastic and non-neoplastic head and neck lesions from surgical procedures performed on 100 patients. The results indicate that the anti-keratin antibody technique can be helpful in several areas of head and neck pathology.

Antibodies↗

Immunohistochemical study of nasopharyngeal carcinoma using monoclonal keratin antibodies.

Nasopharyngeal carcinoma (NPC) provides a unique opportunity to evaluate distinctive epidemiologic features and a possible etiologic relationship with Epstein-Barr virus (EBV) in human malignancy. The lack of a uniformly accepted pathologic classification for NPC has limited the application of this data, although the World Health Organization (WHO) developed a classification that may solve this problem. Monoclonal keratin antibodies were used for staining of NPC for evaluation of its assistance in diagnosis and classification. In the present immunohistochemical study, monoclonal keratin antibodies, designated AE1, AE2, and AE3, and a polyclonal keratin antibody (RAK) were used for study of the presence of keratin in 121 cases of NPC obtained from China and the United States. AE1 monoclonal antibody, which recognizes keratin protein classes 56.5K, 50K, and 40K, was shown to be the most sensitive and specific for NPC tumor cells among the keratin antibodies studied. In addition, some different keratin expression patterns could be identified between different kinds of epithelium and different tumor groups, with possible relevance to the histogenesis of the histologic subtypes of NPC.

Antibodies, Monoclonal↗