A strategy is described for the site-specific conjugation of alkaline phosphatase to the Fc region of immunoglobulins. Mild oxidation of immunoglobulins by sodium periodate followed by reductive amination with excess cystamine and sodium cyanoborohydride covalently attaches cystamine specifically to the oligosaccharide chains of the antibody's Fc region. The disulfide bonds of the conjugated cystamine moieties are then reduced to free thiols with a low concentration of dithiothreitol. The thiol-modified antibodies (typically containing three to four thiols per Fc region) are then brought into contact with maleimide-functionalized alkaline phosphatase to form antibody-alkaline phosphatase conjugates. The Fc site-specific conjugation methodology was optimized and successfully applied to a number of different monoclonal and polyclonal antibodies. The conjugates prepared show assay performances superior to those prepared by more conventional means. Evidence obtained indicates that this superior conjugate performance results from total retention of the antibody's antigen binding activity following the Fc site-specific conjugation procedure.

Alkaline Phosphatase↗

PubMedDate not supplied

Extended length heterobifunctional coupling agents for protein conjugations.

A series of extended length heterobifunctional coupling agents is described. The successive aminocaproic acid homologation of succinimidyl 4-(N-maleimidomethyl)cyclohexane-1-carboxylate, a known 9-atom long maleimide active ester linker, yielded 16-, 23-, and 30-atom long maleimide active ester homologues. The performance study of these coupling agents in automated microparticle enzyme immunoassays showed that, in the alpha fetoprotein assay, in which the linkers were employed in the construction of the alkaline phosphatase-antibody conjugates, the signal increased 64% when the length of the linker was incremented from 9 atoms to 23 atoms and 82% for the 30-atom long linker as compared with the 9-atom homologue. Similar improvements were observed in the performance of carbohydrate antigen, marker of ovarian cancer (CA-125), immunoassay where the linkers were used for conjugation of the capture antibody anti-CA-125 to the microparticle. Thus, a 300% signal improvement resulted when a 30-atom linker was used instead of the 9-atom homologue. The observed differences in the performance of the conjugates are interpreted as resulting from improved antibody binding and lowering of the steric hindrance of the complementarity-determined region of the antibody when longer coupling agents were used.

Alkaline Phosphatase↗

PubMedDate not supplied

Endemic fluorosis presenting as cervical cord compression.

Neurological involvement in fluorosis occurs in the advanced stage of the disease and is due to compression of the spinal cord and/or nerve roots. There are only a few reports on the role of surgical management of these cases in the medical literature. Five cases of fluorosis from the endemic areas of Uttar Pradesh, India, had associated cervical cord compression. Their mean age was 43 yr (range 35-50), and all cases were manual laborers. Three patients with blocked cervical subarachnoid space on myelography underwent laminectomy using local anesthesia. All three cases improved significantly after surgery. The usefulness of laminectomy in selected cases of cervical cord compression due to fluorosis is suggested.

Adult↗

PubMedDate not supplied

MR findings in childhood gangliogliomas.

Gangliogliomas are uncommon primary brain tumors composed of atypical glial and neuronal cells. These tumors usually occur in children and young adults. They are slow-growing tumors that present with seizures. We have reviewed four cases from our institution and have correlated the magnetic resonance (MR) findings with CT and histology. Two distinct patterns were observed with MR. In three of four patients, ranging in age from 7 to 14 years, MR showed a mass with decreased signal on T1-weighted images (WI) and increased signal on T2WI. The most common CT finding was a hypodense enhancing mass with focal calcifications. The histologic features of these tumors comprised microcysts and hypervascularity. In one of four patients, an infant. MR showed increased signal on T1WI and decreased signal on T2WI. Computed tomography showed a hyperdense nonenhancing mass. Histology demonstrated an increase of hypercellularity with both atypical glial and neuronal components.

Adolescent↗

PubMedDate not supplied

Congenital aneurysmal hemorrhage and astrocytoma in an infant.

The authors present the unusual case of an infant who presented at 4 weeks of age with a spontaneous intracerebral hemorrhage due to rupture of a congenital left middle cerebral artery aneurysm. He recovered only to present at 4 months of age with a right frontoparietal desmoplastic cerebral astrocytoma of infancy. The association of brain tumor and aneurysm is discussed, as are the cytogenetic findings associated with this rare form of benign astrocytoma.

Astrocytoma↗

PubMedDate not supplied

Multicenter masked evaluation of AutoCyte PREP thin layers with matched conventional smears. Including initial biopsy results.

OBJECTIVE: To compare the performance of liquid-based cell preparations from the AutoCyte PREP system (AutoCyte, Inc., Elon College, North Carolina) with the conventional cervical smear in masked, split-sample, multisite trials. STUDY DESIGN: The AutoCyte PREP system utilizes the CytoRich method, which combines liquid preservation, selective reduction of blood and inflammation, thin-layer cell dispersion and discrete staining. In an eight-site multicenter trial, 8,983 cases were evaluated. Parallel AutoCyte PREP slides and matching conventional cervical cytologic smears were screened in a masked fashion, with all abnormals reviewed in a masked, on-site pathologist review. The conventional smear was always prepared first, with the AutoCyte PREP using the residual cells on the collection device. The Bethesda System was used for reporting diagnosis and specimen adequacy. RESULTS: Of the cases, 7,805 (86.9%) had the same interpretation. In 8,750 cases (97.4%), there was agreement within one diagnostic category. The AutoCyte PREP demonstrated a statistically significant, 31% overall improvement in the detection of squamous intraepithelial lesion and invasive cancer when evaluating cases with more than one diagnostic class difference. Biopsy correlation of available data supported the improvement observed in the cytology-based comparison. Recovery of infectious organisms and endocervical component was comparable between preparations, especially in light of the split-sample study design. There was a 39% reduction in unsatisfactory slides and 44% fewer satisfactory but limited by reports. CONCLUSION: The AutoCyte PREP and CytoRich method produce excellent cellular presentations with standardized quality, superior sensitivity and improved adequacy as compared to the conventional method.

Adolescent↗

PubMedDate not supplied

Provisions in the laws of Pakistan to combat serious drug-related offences.

British drug control laws were in force in Pakistan until February 1979 when the President of Pakistan promulgated the Prohibition (Enforcement of Hadd) Order, 1979. Under this Order more severe penalties are prescribed for those who violate the regulations of import, export, manufacture or processing of any intoxicants, the term which refers mainly to products of cannabis, opiates and coca derivatives. The Prohibition Order, 1979 and the Dangerous Drugs Act 1930 were amended in December 1983 to provide for further increases in punitive sanctions for offenders violating drug control laws and even more severe sanctions for offenders who are recidivists.

Criminal Law↗

PubMedDate not supplied

Eosinophilic fasciitis in association with thyroid disease: a report of three cases.

We describe 3 patients whose findings fulfilled all the criteria for eosinophilic fasciitis. Unexpectedly, all 3 were found to have thyroid disease: 2 Hashimoto's disease and 1 Grave's disease. One patient also developed multiple subcutaneous nodules of a rheumatoid type. All have been followed for at least 3 yr and shown marked clinical improvement. Corticosteroids were employed in only 1 case.

Adult↗

PubMedDate not supplied

Retroperitoneal extragonadal germ cell tumor diagnosed by needle aspiration cytology and electron microscopy.

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Aged↗

PubMedDate not supplied

Alveolar soft part sarcoma. Report of a case diagnosed by needle aspiration cytology and electron microscopy.

BACKGROUND: Alveolar soft part sarcoma (ASPS) is a rare tumor, accounting for less than 1% of all primary soft tissue malignant neoplasms. The tumor is a distinct clinicopathologic entity, but its histogenesis is controversial. CASE: The needle aspirate from a soft tissue tumor in a 15-year-old girl was stained with Diff-Quik and periodic acid--Schiff (PAS) with and without prior digestion with diastase. Minute tumor tissue fragments were processed for transmission electron microscopic examination (EM). Clustered malignant cells with ill-defined, frothy or vacuolated cytoplasm showed a positive reaction with PAS and PAS with prior diastase digestion and oval nuclei containing macronucleoli. Intracytoplasmic, membrane-bound, rhomboid and rod-shaped crystals with a regular lattice pattern with 50-80 A periodicity were detected by EM study of aspirated tumor cells. CONCLUSION: Light and EM studies of aspirated tumor cells showed diagnostic features of the tumor.

Adolescent↗

PubMedDate not supplied

Primary pulmonary plasmacytoma diagnosed by transthoracic needle aspiration cytology and immunocytochemistry.

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Adolescent↗