Kinetics of receptor-mediated radiotoxicity of 16alpha-[125I]-iodostradiol-3,17beta

AIM: The radiocytotoxic effects in estrogen receptor (ER) containing MCF-7 cells of a mamma carcinoma were investigated following incubation with [125I]E ranging from 1 h to 24 h. METHODS: The receptor status of the cells was confirmed by immunohistochemical staining. The accumulation of [125I]E in MCF-7 cells was tested in the presence and absence of radioinert E and [127I]E and in ER-negative cells in comparison to ER-positive cells. The subcellular distribution was investigated in 0.25 M Saccharose by ultra centrifugation. The radiocytotoxicity was assessed in ER-positive and negative cells by a standard colony forming assay after incubating with [125I]E (1.85 kBq/ml-55.5 kBq/ml) for 1, 2, 4, 8, 12, and 24 h. RESULTS: A significant cytotoxicity was observed only when ER-rich MCF-7-cells were incubated with [125I]E alone. The maximal cytotoxic effect was a reduction of survival fraction to 20-25%. This was achieved at radioactivity concentrations > 37 kBq/ml. Maximal effect was seen after 8 h incubation, extension of incubation time did not further increase toxicity. CONCLUSION: The results suggest that the radioactivity was bound to ER. Through their nuclear localization radioestrogens tagged with radionuclides emitting very low energy electrons (Auger electrons) bear potential for therapy by ER-mediated deposition of lethal doses of ionizing radiation to single cells without affecting neighbouring cells. But, instead of 125I the shorter-living 123I shall be used for labelling because the deciding radiation effectes occur within the first 8 h.     

The Golgi and endoplasmic reticulum remain independent during mitosis in HeLa cells

Partitioning of the mammalian Golgi apparatus during cell division involves disassembly at M-phase. Despite the importance of the disassembly/reassembly pathway in Golgi biogenesis, it remains unclear whether mitotic Golgi breakdown in vivo proceeds by direct vesiculation or involves fusion with the endoplasmic reticulum (ER). To test whether mitotic Golgi is fused with the ER, we compared the distribution of ER and Golgi proteins in interphase and mitotic HeLa cells by immunofluorescence microscopy, velocity gradient fractionation, and density gradient fractionation. While mitotic ER appeared to be a fine reticulum excluded from the region containing the spindle-pole body, mitotic Golgi appeared to be dispersed small vesicles that penetrated the area containing spindle microtubules. After cell disruption, M-phase Golgi was recovered in two size classes. The major breakdown product, accounting for at least 75% of the Golgi, was a population of 60-nm vesicles that were completely separated from the ER using velocity gradient separation. The minor breakdown product was a larger, more heterogenously sized, membrane population. Double-label fluorescence analysis of these membranes indicated that this portion of mitotic Golgi also lacked detectable ER marker proteins. Therefore we conclude that the ER and Golgi remain distinct at M-phase in HeLa cells. To test whether the 60-nm vesicles might form from the ER at M-phase as the result of a two-step vesiculation pathway involving ER-Golgi fusion followed by Golgi vesicle budding, mitotic cells were generated with fused ER and Golgi by brefeldin A treatment. Upon brefeldin A removal, Golgi vesicles did not emerge from the ER. In contrast, the Golgi readily reformed from similarly treated interphase cells. We conclude that Golgi-derived vesicles remain distinct from the ER in mitotic HeLa cells, and that mitotic cells lack the capacity of interphase cells for Golgi reemergence from the ER. These experiments suggest that mitotic Golgi breakdown proceeds by direct vesiculation independent of the ER.     

Increased density of microtubule associated protein 2-immunoreactive neurons in the prefrontal white matter of schizophrenic subjects

Recent studies have suggested that schizophrenia may be related to prenatal disturbances in the cortical subplate, a transient but essential structure in the formation of cerebral cortical circuitry. Although most subplate neurons die during later development, some remain as the interstitial neurons of the adult white matter. In this study we used a monoclonal antibody against the cytoskeletal protein, microtubule associated protein-2 (MAP2), to quantify the density and distribution of labeled neurons in postmortem brain specimens containing the prefrontal white matter from five schizophrenic cases and matched controls. In both schizophrenics and matched controls, the density of white matter neurons decreased with increasing white matter depth. However, the mean density of MAP2-immunoreactive neurons was greater in the superficial white matter of the schizophrenic subjects compared to the matched controls. In contrast, no difference in the density of labeled neurons was seen in the deeper white matter. These findings are consistent with an abnormality in the development of the cortical subplate in at least some cases of schizophrenia.     

Phenotypic analysis of donor cells infiltrating the small intestinal epithelium and spleen during graft-versus-host disease

A pyriform sinus fistula can cause acute thyroiditis or recurrent infection in the neck. This fistula is believed to be a remnant of the branchial apparatus, although its origin has yet to be pinpointed. The spatial distribution of C cells in the thyroid gland was mapped by immunohistologic method in four patients with a pyriform sinus fistula. The C cells were identified immunohistologically with anticalcitonin antibody. The stained calcitonin-positive cells also crossreacted with the antibodies to carcinoembryonic antigen, chromogranin A, and neuron-specific enolase. The C cells were mainly distributed near the end of the fistula, and in three patients their concentration per unit volume of thyroid tissue was found to be inversely proportional to the distance from the end of the fistulas. Comparison of distant locations of the left-sided thyroid lobe in patients and the same region in control subjects showed a similar number of C cells. Thus this limited distribution of C cells suggested that the pyriform sinus fistula was either a remnant of the ultimobranchial body, the result of disturbed migration of the C cell in the fetus, or both.     

Opitz oculo-genito-laryngeal syndrome: a rare cause of recurrent aspiration pneumonia in an adult

A 64 year old woman presented with persistent and severe symptoms due to recurrent aspiration pneumonias associated with oesophageal reflux. She had had multiple miscarriages and her son at birth had widely spaced eyes (hypertelorism), hypospadias, bilateral undescended testes, and an imperforate anus. Her daughter has mild hypertelorism and her daughter's son had neonatal inspiratory stridor, hypospadias and hypertelorism, all features now recognised as typical of the Opitz oculo-genito-laryngeal syndrome. This syndrome is genetically heterogeneous with autosomal dominant (linked to chromosome 22q21) and X-linked (linked to Xp22) inheritance. This family's history and genetic linkage data are consistent with linkage to Xp22. The proband is a manifesting carrier of this syndrome; her history of recurrent aspiration is probably secondary to pharyngeal neuromuscular incoordination aggravating gastro-oesophageal reflux. Obtaining a family history gives a vital clue to the diagnosis of Opitz oculo-genito-laryngeal syndrome. It is also suggested that this condition should be included in the differential diagnosis of recurrent aspiration pneumonia.     

Astrocyte-derived monocyte-chemoattractant protein-1 directs the transmigration of leukocytes across a model of the human blood-brain barrier

The migration of leukocytes across the blood-brain barrier (BBB) into the central nervous system is critical in the pathogenesis of central nervous system inflammatory diseases. The production of chemokines, such as monocyte-chemoattractant protein-1 (MCP-1), by endothelial cells (EC) and astrocytes may initiate and amplify this process. Using a coculture of human EC and astrocytes to model the BBB, we demonstrated that exogenous MCP-1 induces the transmigration of monocytes in a dose-dependent manner. TNF-alpha, IFN-gamma, or IL-1beta treatment of cocultures also induced significant migration of monocytes that correlates with the induction of MCP-1 protein. TGF-beta, previously shown to induce MCP-1 expression in astrocytes, but not in EC, caused migration of monocytes across cocultures, but not across EC grown alone. Monocytes and lymphocytes transmigrated across cytokine-treated cocultures in greater numbers than across EC alone. Astrocytes were the main source of cytokine-induced MCP-1, supporting a role for astrocytes in facilitating leukocyte transmigration. A blocking Ab to MCP-1 inhibited MCP-1- and cytokine-induced transmigration of monocytes by 85-90%. Cytokine treatment of cocultures also resulted in the transmigration of activated, CD69-positive lymphocytes. The MCP-1-mediated transmigration of monocytes across cocultures was blocked using an Ab to ICAM-1 and inhibited by 55% using an Ab to E-selectin. These data suggest a central role for astrocyte-derived MCP-1 in directing the migration of monocytes and lymphocytes across the BBB.     

Expression of peroxisome proliferator activated receptor mRNA in normal and tumorigenic rodent mammary glands

PURPOSE: To evaluate the usefulness of Doppler ultrasonography (US) in the diagnosis of hyperfiltration in patients with insulin-dependent diabetes mellitus (IDDM). MATERIALS AND METHODS: Eighty-one consecutive patients with IDDM were studied. All patients were normotensive and had normal creatinine and blood urea nitrogen levels. The glomerular filtration rate (GFR) was evaluated by means of plasma clearance of chromium-51 ethylenediaminetetraacetic acid, urinary albumin excretion, US evaluation of renal volume, and Doppler evaluation of resistance index (RI) in the renal interlobar arteries. The patients were divided according to GFR into the following groups: those with hyperfiltering kidneys (group 1, n = 40) and those with normofiltering kidneys (group 2, n = 41). RESULTS: The median renal volume was 351 mL (95% CI = 337 mL, 379 mL) in group 1 and 318 mL (95% CI = 300 mL, 335 mL) in group 2 (P = .005). The number of patients with microalbuminuria was significantly lower in group 1 than in group 2 (P = .02). The median RI was significantly lower in group 1 (0.55; 95% CI = 0.53, 0.57) than in group 2 (0.57; 95% CI = 0.56, 0.59) (P = .04). An RI of less than 0.5, a renal volume greater than 410 mL/m2, and the absence of microalbuminuria were independent predictors of hyperfiltration. An RI of less than 0.5 and a renal volume greater than 410 mL/m2 showed high specificity (98% and 95%, respectively) and poor sensitivity (25% and 23%, respectively) in the diagnosis of hyperfiltration in IDDM patients. CONCLUSION: Both RI and renal volume showed correlation with GFR, but neither parameter is sufficiently sensitive in screening for hyperfiltration in IDDM patients.     

Surgical management of patients with persistent or recurrent medullary thyroid cancer

OBJECTIVE: To compare estimates based on vaccination cards, parental recall, and medical records of the percentages of children up-to-date on vaccinations for diphtheria, tetanus, and pertussis; polio; and measles, mumps, and rubella. METHOD: The authors analyzed parent interview and medical records data from the Baltimore Immunization Study for 525 2-year-olds born from August 1988 through March 1989 to mothers living in low-income Census tracts of the city of Baltimore. RESULTS: Only one-third of children had vaccination cards; based on medical records, these children had higher up-to-date coverage at 24 months of age than did children without cards. For individual vaccines, only two-thirds of parents could provide information to calculate coverage rates; however, almost all provided enough information to estimate coverage for the primary series. For each vaccine and the series, parental recall estimates were at least 17 percentage points higher than estimates from medical records. For children without vaccination cards whose parents could not provide coverage information, up-to-date rates based on medical records were consistently lower than for children with cards or with parents who provided coverage information. CONCLUSIONS: Population-based vaccine coverage surveys that rely on vaccination cards or parental recall or both may overestimate vaccination coverage.     

Improvement of some pharmaceutical properties of drugs by cyclodextrin complexation. 4. Chlorpromazine hydrochloride

This study is a retrospective review of admissions, discharge records and blood culture results of neonates admitted to the Neonatal Intensive Care Unit of Korle Bu Teaching Hospital in Accra, from the first of January 1991 to the 31st of December 1992. During this two year period there were 443 positive blood cultures. Ninety percent of the blood cultures were from babies born in Korle Bu Teaching Hospital, thus making the incidence of neonatal bacteraemia 22.2 per 1000 live births. The overall mortality rate was 37.2%. Gram negative bacteria accounted for 70.9% and Gram positive bacteria for 29.1% of all neonatal bacteraemia. The most common isolates were Enterobacter species 29.6%; Streptococcus faecalis 14.4%; Staphylococcus aureus 10.8%; Acinetobacter species 9.5%; Klebsiella species 9% and Escherichia coli 8.8%. It is concluded that the incidence of neonatal bacterial sepsis is high in our hospital and is associated with a very high mortality rate. There is thus an urgent need to institute appropriate preventive and therapeutic measures.     

Word completion in chronic pain: evidence for schematic representation of pain?

Schematic representation of pain information was investigated in chronic pain patients, health professionals, and nonpatient controls. Under the guise of an English-language experiment, Ss were presented with 12 word stems to be completed with the first 2 English words that came to mind. Four of the stems could be completed with sensory pain words, 4 with effective, and 4 with words associated with pain or illness. All could be completed with at least 3 other nonpain words of equal or greater frequency. Results indicate that chronic pain Ss produced significantly more pain-related completions than control Ss and that in all 3 groups the types of pain words produced were related to the extent of personal experience of pain. The theoretical implications of these findings are discussed in relation to the organization of schema, implicit memory, and the activation of mental representations of pain (schema).