Detection and characterization of carcinoma cells in the blood

A highly sensitive assay combining immunomagnetic enrichment with multiparameter flow cytometric and immunocytochemical analysis has been developed to detect, enumerate, and characterize carcinoma cells in the blood. The assay can detect one epithelial cell or less in 1 ml of blood. Peripheral blood (10-20 ml) from 30 patients with carcinoma of the breast, from 3 patients with prostate cancer, and from 13 controls was examined by flow cytometry for the presence of circulating epithelial cells defined as nucleic acid+, CD45(-), and cytokeratin+. Highly significant differences in the number of circulating epithelial cells were found between normal controls and patients with cancer including 17 with organ-confined disease. To determine whether the circulating epithelial cells in the cancer patients were neoplastic cells, cytospin preparations were made after immunomagnetic enrichment and were analyzed. Epithelial cells from patients with breast cancer generally stained with mAbs against cytokeratin and 3 of 5 for mucin-1. In contrast, no cells that stained for these antigens were observed in the blood from normal controls. The morphology of the stained cells was consistent with that of neoplastic cells. Of 8 patients with breast cancer followed for 1-10 months, there was a good correlation between changes in the level of tumor cells in the blood with both treatment with chemotherapy and clinical status. The present assay may be helpful in early detection, in monitoring disease, and in prognostication.

A short-term plaque study using Lactitol as a non-sugar sweetener

A short-term plaque study was undertaken in a group of 12 children of 8-12 years age to evaluate the effect of lactitol, 4-O (beta-galactosyl)-D-glucitol, on dental plaque pH, weight and microchemical composition. Sucrose which was taken as control and lactitol, were used in both solution form and sweets. Plaque pH recording was done at rest and post consumption periods at 5, 10, 20 and 30 minute intervals. Weight and microchemical analysis were done with 3-day-old plaque after consumption of sweets. Throughout the study period lactitol did not reach to a pH where the demineralization of enamel starts. A significant reduction in plaque formation, carbohydrate content, increase in calcium, phosphorus and protein in lactitol showed the potentiality of this bulk sweetener as non-cariogenic.

Incidence of extrapyramidal syndromes in AIDS patients and a comparison group of medically ill inpatients

The authors retrospectively reviewed the charts of 29 inpatients with AIDS and 24 medically ill inpatients, all of whom were exposed to neuroleptics. Results adjusted for age, gender, type and dosage of neuroleptic, and extrapyramidal prophylaxis indicated that inpatients with AIDS were 7 times more likely to develop extrapyramidal syndromes (EPS) from neuroleptics than the comparison group of medically ill inpatients. Possible neuroanatomic, neuropathologic, and neurochemical reasons for the vulnerability of patients with AIDS to EPS are reviewed.

Microencephaly in children congenitally infected with human immunodeficiency virus--a gross-anatomical morphometric study

A quantitative technique involving serial sectioning and semiautomatic morphometric analysis was used to assess the severity of the reduction in size of the major brain structures in cerebral hemispheres of children congenitally infected with HIV-1. Cerebral hemispheres from 12 children (18-48 months of age) who died of AIDS were sectioned into 5-mm-thick serial slabs and photographed. The cross-sectional areas of grossly recognizable brain structures were digitized, and the volumes were calculated according to Cavalieri's principle. The results were compared with those of an identically processed group of control brains from non-AIDS children. Analysis of the brain weight showed that there was a significant reduction in supratentorial and infratentorial weight in the AIDS group. The results of the morphometric study revealed that the loss in brain mass was associated with a statistically significant reduction in the total volume of both hemispheres, the entire cortex, white matter, and basal ganglia. Detailed analysis of individual brain structures also showed a significant reduction in volume of all cortical regions and most of the subcortical gray matter (e.g., caudate nucleus, putamen, globus pallidus, claustrum, and thalamus). It appears that in the microencephaly observed as a frequent sequel in pediatric AIDS, the loss of brain tissue is global and includes an almost proportional loss of cortex, subcortical gray matter and white matter.

Opportunistic infections of the central nervous system in children with HIV infection: report of 9 autopsy cases and review of literature

Central nervous system (CNS) abnormalities attributed to direct effects of HIV infection are seen in most of children with acquired immunodeficiency syndrome (AIDS). Secondary CNS infections with opportunistic and common pathogens are infrequent in this age group. We report 9 cases of opportunistic infection of the CNS found among 65 autopsy cases of pediatric AIDS. These included 4 cases of cytomegalovirus (CMV) infection, 1 of which was associated with aspergillosis, and 2 cases of candidiasis, 1 of which coexisted with Mycobacterium avium intracellulare (MAI) infection. There were also 2 cases of leptomeningitis, 1 due to Mycobacterium tuberculosis (MTB) and the other to Cryptococcus neoformans. In 1 child progressive multifocal leukoencephalopathy (PML) coexisted with mycotic encephalitis caused by an Aspergillus sp.

Specificity and formation of unusual amino acids of an amide ligation strategy for unprotected peptides

An important step in the recently developed ligation strategy known as domain ligation strategy to link unprotected peptide segments without activation is the ring formation between the C-terminal ester aldehyde and the N-terminal amino acid bearing a beta-thiol or beta-hydroxide. A new method was developed to define the specificity of this reaction using a dye-labeled alanyl ester aldehyde to react with libraries of 400 dipeptides which contained all dipeptide combinations of the 20 genetically coded amino acids. Three different ester aldehydes of the dye-labeled alanine: alpha-formylmethyl (FM), beta-formylethyl (FE), and beta,beta,beta-dimethyl and formylethyl esters (DFE), were examined. The DFE ester was overly hindered and reacted with N-terminal Cys dipeptides (Cys-X). Interestingly, it also reacted slowly with the sequences of X-Gly where Gly was the second amino acid and the X-Gly amide bond participated in the ring formation. Although the FE ester reacted similarly as the FM ester in the ring formation, the subsequent O,N-acyl transfer was at least 30-fold slower than those of the FM-ester. The FM alpha-formyl methyl ester was the most suitable ester and was reactive with dipeptides of six N-terminal amino acids: Cys, Thr, Trp, Ser, His and Asn. The order and extent of their reactivity were highly dependent on pH, solvent and neighboring participation by the adjacent amino acid. In general, they could be divided into three categories. (1) N-Terminal Cys and Thr were the most reactive.(ABSTRACT TRUNCATED AT 250 WORDS)

A syndrome of hypotonia, psychomotor retardation, seizures, delayed and dysharmonic skeletal maturation, and congenital fibre type disproportion

Three unrelated Puerto Rican boys, ranging in age from 3 to 4 years, had marked, central, non-progressive hypotonia, chronic constipation, severe psychomotor retardation, seizures or abnormal electroencephalograph or both, abnormal dermatoglyphics, delayed bone age, dysharmonic skeletal maturation, and preponderance and larger size of type 2 muscle fibres. Additional findings included narrow, high arched palate, prominent nasal root, long philtrum, distended abdomen, and drooling from open mouth. Two of the three patients also had undescended testes, hypertelorism, and tapered fingers. Birth weight, postnatal physical growth, and head size were average. Family and gestational histories and laboratory evaluations were normal. The combination of features observed in the three boys appears to be distinct and to represent a new syndrome.

A novel strategy for the synthesis of the cysteine-rich protective antigen of the malaria merozoite surface protein (MSP-1). Knowledge-based strategy for disulfide formation

The most promising antigen for a protective malaria vaccine is a cysteine-rich domain at the carboxyl terminus of the merozoite surface protein (MSP-1). Passive transfer of anti-MSP-1 antibody or immunization of MSP-1 against infection challenge confers protection in primate and rodent models. The antigen belongs to the three-disulfide epidermal growth factor (EGF) family based on the alignment of the six cysteines. In the K1 strain there are, however, only four cysteines corresponding to the four carboxyl cysteines of EGF. Furthermore, disulfide pairing would produce a non-EGF pattern. Because this cysteine-rich antigen is conformation-dependent, and reduction of the disulfide bonds abolishes antigenicity, we used a synthetic analog to investigate the probable disulfide pairing of this antigen. This paper describes the synthesis, folding and disulfide pairings of two 50-residue cysteine-rich peptides. One contains two disulfides (VK-50) derived from the native sequence of MSP-1 of the Thailand K1 strain (aa 1629-1679). The other contains an EGF-like, three-disulfide [Cys-9,14]VK-50 peptide. Both peptides were synthesized by a solid-phase method using Fmoc-chemistry. The crude peptide of VK-50 was folded, and the disulfide was oxidized by the DMSO method to obtain a structure with an expected disulfide pairing of 3-4, and 5-6. The specific pairing pattern of 1-3, 2-4 and 5-6 in [Cys 9,14]VK-50 corresponding to EGF in [Cys 9,14]VK-50 was obtained using a 'knowledge-based' (KB) strategy for their formation.(ABSTRACT TRUNCATED AT 250 WORDS)

Sudden death due to coronary artery anomalies: a case report and clinical review

Congenital anomalies of the coronary arteries are relatively uncommon conditions with an incidence of approximately 2% in the adult population. Although less common than acquired coronary artery disease, these anomalies may be associated with myocardial ischemia and its consequences; angina, arrhythmia, infarction, and sudden death. A 21-year-old female patient with no significant prior medical history was found dead at home. Postmortem examination revealed high take-off of the right coronary artery with acute down-ward angulation of the proximal right coronary artery and acute downward angulation of the left main coronary artery. Microscopic examination revealed global myocardial ischemia consistent with a terminal ventricular dysrhythmia. There was no evidence of any other disease processes. Detailed toxicological investigation was negative. The Regional Forensic Pathology Unit experience with sudden death due to congenital coronary artery anomalies is presented along with a review of the current literature.

Comparative pharmacokinetics and amoebicidal activity of metronidazole and satranidazole in the golden hamster, Mesocricetus auratus

The pharmacokinetic properties of metronidazole and satranidazole were studied in the golden hamster (Mesocricetus auratus), at a dose of 80 mg/kg po. Blood and liver samples were collected at frequent time intervals and assayed for metronidazole and satranidazole by HPLC. Satranidazole exhibited significantly higher plasma concentrations than metronidazole at 1 and 2 h post-dose, but the comparative Cmax values were not significantly different. The satranidazole plasma elimination half-life of 1.01 h was significantly shorter than the corresponding metronidazole half-life of 3.62 h. The comparative liver pharmacokinetic parameters Cmax, Tmax and T1/2 did not differ significantly. Satranidazole however exhibited significantly higher liver concentrations at 1 h post-dose and Cmax and AUC0-infinity values were approximately 35% higher. The in-vivo amoebicidal activity of both compounds was evaluated in the acute hamster hepatic model of amoebiasis. Both metronidazole and satranidazole were administered as single graded doses po, and their dose-response profiles were characterized. Satranidazole demonstrated significantly greater amoebicidal activity than metronidazole with an ED50 value of 19.5 mg/kg, compared to an ED50 value of 45 mg/kg for metronidazole. These data suggest that higher plasma and liver concentrations of satranidazole and greater intrinsic potency probably contribute to superior amoebicidal activity in the hamster model of hepatic infection.

Noncommunicating syringomyelia following occlusion of central canal in rats. Experimental model and histological findings

This report describes a new and reliable technique for producing experimental noncommunicating syringomyelia. In 30 rats, 1.2 to 1.6 microliters of kaolin was microinjected into the dorsal columns and central gray matter of the spinal cord at C-6. The inoculations caused transient neurological deficits in four animals and no deficits in 26 animals. Within 24 hours, kaolin and polymorphonuclear leukocytes entered the central canal and drained rostrally. The clearance of inflammatory products induced a proliferation of ependymal cells and periependymal fibrous astrocytes, which formed synechiae and obstructed the canal at the level of injection and at one or more levels up to C-1. In 22 animals followed for 48 hours or longer, the upper end of the central canal became acutely dilated and formed an ependyma-lined syrinx that enlarged to massive dimensions within 6 weeks. The rostral syrinxes did not communicate with the fourth ventricle and were not associated with hydrocephalus. The histological findings in acute noncommunicating syringomyelia were characterized by progressive stretching and thinning of the ependyma, elongation of intracanalicular septae, and the formation of periependymal edema. After 3 weeks, there was progressive compression of the periependymal tissues associated with stretching of axons, fragmentation of myelin sheaths, and the formation of myelin droplets. These findings and the sequence in which they evolved were identical in most respects to those occurring in acute and subacute noncommunicating hydrocephalus.

Phenylephrine prodrug. Report of clinical trials

The authors evaluated the mydriatic effect of phenylephrine oxazolidine prodrug, a lipophilic sympathomimetic that undergoes hydrolysis to phenylephrine as it passes through the cornea and aqueous humor. Double-masked clinical trials were performed randomizing 66 healthy subjects to receive either the silicone vehicle as a placebo, 10% viscous phenylephrine hydrochloride (HCl), or prodrug in 0.25%, 0.50%, or 1.0% concentrations. A mean horizontal pupillary diameter of 8.8 mm was achieved in 30 minutes in those receiving 1% prodrug versus 6.5 mm obtained at 30 minutes with 10% viscous phenylephrine HCl. Statistically, this difference was highly significant at P less than or equal to 0.0001. There were minimal systemic or ocular adverse effects from any preparation.

Amebic meningoencephalitis in a patient with AIDS caused by a newly recognized opportunistic pathogen. Leptomyxid ameba

A fatal case of meningoencephalitis due to a leptomyxid ameba in a patient with the acquired immunodeficiency syndrome is presented. This opportunistic organism has not been previously recognized as a human pathogen. A 36-year-old male intravenous drug abuser died after an 18-day hospital course heralded by fever and headache and followed by nuchal rigidity and hemiparesis. Computed tomography of the head showed multiple hypodense lesions. Neuropathologic examination showed that in addition to human immunodeficiency virus encephalomyelitis, there was multifocal meningoencephalitis with trophozoites and cysts morphologically indistinguishable from those of Acanthamoeba. These organisms were also found in the kidneys and adrenal glands. By immunofluorescence, the parasites showed antigenic identity with a free-living leptomyxid ameba and failed to react with any of a spectrum of antiacanthamoeba antisera. This emphasizes the importance of immunofluorescence identification of morphologically indistinguishable ameba species.

Skeletal muscle pathology in AIDS: an autopsy study

A survey of skeletal muscle pathology in 92 autopsied cases of AIDS revealed microscopic alterations in 64 cases. There were 40 cases of disuse atrophy, 8 of denervation atrophy, 2 of cryptococcal myositis, 1 of Mycobacterium avium intracellulare (MAI) infection and 2 of necrotizing myopathy associated with hyperkalemia. A second group of cases with changes of unknown etiology was found. These were tentatively ascribed to the direct or indirect action of HIV. This category includes 8 cases of inflammatory myopathy, 8 of necrotizing myopathy in absence of a known etiological factor, 3 of extreme atrophy and 4 of "regenerating" myopathy.

Prevention of myelinolysis in rats by dexamethasone or colchicine

The purpose of the present investigation was to determine whether dexamethasone, an agent known to preserve the blood-brain barrier, and colchicine, an agent that impairs mobilization of macrophages, can prevent demyelinating lesions associated with rapid correction of hyponatremia in the experimental animal. Hyponatremia was induced in rats with Pitressin and water. After 4 days hyponatremic rats received hypertonic saline alone or hypertonic saline plus dexamethasone or colchicine. All of the 9 rats that received only 5% NaCl developed demyelinating disease, while 3 of 6 rats treated with dexamethasone and 5 of 15 rats treated with colchicine showed no CNS abnormality. The results of our investigation might help understand the pathogenetic mechanism of central pontine myelinolysis in humans, a disease attributed to rapid correction of hyponatremia.

Medullomyoblastoma in an adult

Medullomyoblastoma is a rare histologic variant of medulloblastoma. Of the 20 cases reported in the literature, 19 were in children ages 2.5 to 10.5 years and one was in a 26-year-old woman. In the reported adult case the myogenic component of the tumor was leiomyosarcomatous. The authors report a case of medullomyoblastoma with a rhabdomyosarcomatous component in a 40-year-old man with light microscopic, immunohistochemical, and ultrastructural findings. The histogenetic theories regarding this tumor include that it is a teratoma, or that the myogenic component arises from the perivascular or leptomeningeal ectomesenchyme, or pluripotential neuroectodermal cells, or endothelial cells. The authors' findings do not elucidate the histogenesis but argue against an endothelial origin of the rhabdomyoblastic component.

A semi-Markovian model for predator-prey interactions

In the study of population dynamics, the predator-prey system is recognized as a vitally important aspect in natural population control. On aspect of predator-prey interactions is studied in this paper. The attack cycle of a predator is assumed to consist of four different activities, namely, search, pursuit, handle and eat, and digestion. A semi-Markovian model is proposed to obtain the number of prey devoured by a predator during the activity of a day. The advantages of a new semi-Markovian model to the queueing model developed by Curry and DeMichele (1977) is demonstrated, as the results from the semi-Markovian model are closer to Holling's (1966) experimental data than their results, which were based entirely on Poisson assumptions.

Correlation of light and scanning electron microscopy a new method for exfoliative cytology

A method for preparing locator slides for light and scanning electron microscopy has been developed. These slides make possible correlation of light and scanning electron microscopy of individual cells. Some examples of the value of this method are given.