Expression of basic helix-loop-helix proteins in the glomeruli.

BACKGROUND: Basic helix loop helix (bHLH) proteins play a critical role in the differentiation of not only striated muscle cells but also adipocytes, neuron cells and smooth muscle cells. Previous studies have established in vitro mouse mesangial cells (MCs) to maintain the differentiated smooth muscle phenotype. MATERIALS AND METHODS: The purpose of the present study was to clone bHLH proteins from these MCs using the primers designed from a homologous sequence specific to bHLH, and to analyze the presence of bHLH proteins in normal kidney in vivo. From the cloning of MCs in vitro, we identified myf5 and herculin mRNA but not myoD. The expression of bHLH proteins in vivo was examined by immunohistochemistry with each specific antibody. RESULTS: The MCs in newborn mice possessed Id but did not express either protein herculin or myoD. On the other hand, mature MCs expressed both myf5 and herculin. The Id protein disappeared in mature glomeruli. CONCLUSION: These results suggest that bHLH proteins are an important factor for mature MCs in vivo.

Intraperitoneal administration of anti-c-fms monoclonal antibody prevents initial events of atherogenesis but does not reduce the size of advanced lesions in apolipoprotein E-deficient mice.

BACKGROUND: Atherosclerosis results from complex inflammatory-fibroproliferative responses. To elucidate the central role of macrophage and macrophage-colony stimulating factor (M-CSF) during atherogenesis, we used a new strategy to administer to adult apolipoprotein E (apoE)-deficient mice a monoclonal antibody (AFS98) raised against c-fms, the receptor of M-CSF. METHODS AND RESULTS: When 6-week-old apoE-deficient mice were fed a high-fat diet and injected with 2 mg of AFS98 intraperitoneally on alternate days for 6 weeks, accumulation of macrophage-derived foam cells in the aortic root was suppressed by 70% compared with that in controls. This preventive effect was associated with neither remarkable decrease of the number of circulating monocytes nor systemic growth retardation. In contrast, when apoE-deficient mice that had been fed a high-fat diet from 6 weeks of age were given AFS98 from 12 to 18 weeks of age, a minimal protective effect on lesion size was observed. CONCLUSIONS: These results suggest that (1) macrophage and M-CSF/c-fms play an essential role in the arterial wall during development of the fatty streak lesion and (2) blockade of the M-CSF/c-fms pathway could act as protection from at least early atherogenesis but could have a less preventive effect on maintenance of the advanced lesions.

[Pulmonary edema due to acute airway obstruction immediately after tracheal extubation].

A 33-year-old male was scheduled for tonsillectomy and pharyngoplasty due to sleep apnea syndrome. The intubation was uneventful following induction with thiamylal and vecuronium. Anesthesia was maintained with O2-N2O-sevoflurane. No complications were observed during the 90 min operation. After the termination of the anesthesia, a hyperadrenergic state was observed: arterial pressure and heart rate rose to 230/135 mmHg and 135 bpm, respectively. Immediately after extubation, he developed dyspnea with tracheal tag and stridor, and became cyanotic despite the use of a simple oxygen mask and assisted ventilation. Laryngospasm was suspected. The patient was reintubated and suctioned; pink, frothy sputum was not obtained. Arterial blood gases 5 minutes after reintubation revealed a pH of 7.24, Pao2 86 mmHg (FIo2 1.0), and Paco2 54 mmHg. Chest X-ray 30 minutes after reintubation revealed bilateral diffuse alveolar infiltration. The diagnosis was interstitial pulmonary edema. The patient was ventilated mechanically by applying a positive end-expiratory pressure of 5cm H2O, and furosemide and dopamine were administered intravenously. The patient was extubated the next day, and discharged from hospital ten days later. We considered that the lung edema was induced by the severe negative pressure generated by inspirating against a closed upper airway, as well as by the hyperadrenergic state and severe hypoxemia observed during and after extubation.

Differentiation of smooth muscle phenotypes in mouse mesangial cells.

Smooth muscle alpha-actin (SMA) mRNA, a marker of vascular smooth muscle cells, was identified in the normal glomerular mesangium both in vivo and in vitro. Several populations of mesangial cells were studied to determine if SMA and basement membrane collagen were regulated together. The levels of SMA expression, which could be linked to the stage of differentiation, were different for the differing cell populations. One cell population had high SMA and type IV collagen levels at its early passages. The others expressed both interstitial and basement membrane collagens. The first population developed these phenotypic features at later passages. The levels of SMA and alpha 1(IV) collagen expression were regulated together in concert, whereas the alpha 2(I) collagen levels were expressed inversely to SMA and alpha 1(IV) collagen. Both SMA and type IV collagen were controlled by the methylation states of the cis-regulators; however, type I collagen was mainly regulated by the trans-acting regulators. Treatment with 5-azacytidine converted the cells of a fibroblast-phenotype to a smooth muscle cell-like phenotype. These cell lines may be useful for studying the differentiation process in vitro.

Elevated levels of dolichol in the brains of mucopolysaccharidosis and related disorders.

The contents of total dolichol were measured in the cerebral cortex of various patients with lysosomal storage disorders, including mucopolysaccharidosis. Strikingly high levels of dolichol were demonstrated in GM1-gangliosides, Sanfilippo B syndrome, and a severe type of Hunter syndrome as well as neuronal ceroid-lipofuscinosis. An increased level of dolichol in cerebral cortex in neuronal ceroid-lipofuscinosis (NCL) was once regarded as pathognomonic for NCL. Our data, however, suggest that an increased level of dolichol in cerebral cortex is a nonspecific phenomenon related to some lysosomal dysfunction secondary to various neurodegenerative disorders.

[A homicidal strangulation by ligature, disguised as a suicidal hanging].

A naked 38-year-old woman was found dead, lying beside a bed in a guest room of a hotel. A cotton cord was looped around her neck, with one end tied to a bedpost. Thus it seemed that she had hanged herself in a lying position. Yet, certain suspicious factors gave rise to doubts. The hair and a necklace were intertwined with the cord and a man that had been staying in the same room had fled. On the postmortem examination, marked congestion and many petechial haemorrhages were seen in the face and the upper area of the neck, also in conjunctiva. A light-brown and highly dry ligature mark, about one centimeter in width, was found on the neck. The mark, crossing the front of the neck, was clearly evident from the back to the right side of the neck. The lower borders of the congestion and petechial haemorrhages in the face and neck were located 1 or 2 centimeters above the ligature mark. On the left side of the neck, another pale ligature mark with slight subcutaneous haemorrhages was seen between the dry mark and the lower border of the congested part of the neck. A similar ligature mark also was found on the back of the neck. On internal examination, congestion of the cervical lymph nodes and haemorrhages in the cervical muscles were recognized in the areas of the cutaneous congestion. These findings supported suspicions that the dry ligature mark had been caused by hanging after her death, and that the light ligature mark with slight subcutaneous haemorrhages on the left side and back of the neck had been caused by strangulation, which had brought on the victim's death. Therefore, it was decided that her death had been disguised as a suicidal hanging, after she had been strangled by ligature. A week later, her former husband was arrested and confessed his crime.

[Unusual calcification in brain suspected to be caused by toxoplasmosis: a report of an autopsy case].

A very rare case of severe calcification in brain is reported. A 49-year-old man was hit and run by a motorcar in acrossing a road on foot, and he died 1 hour later in an emergency hospital. Medico-legal autopsy was done at 5 hours after his death. The cause of death was cerebral contusion caused by a struck on partieto-occipital region. Unusually severe calcification was observed in the right and left cerebral hemispheres, especially basal ganglia, in the border areas between grey and white matters of frontal, parietal and occipital lobes, as well as in the cerebellar nucleus, cortex and medulla. Histological examination showed severe multiple calcification in the brain tissue. Dispersed deposit of pseudocalcium-Ca and edema were observed around the calcifications. Proliferation of glia cells and decrease of nerve cells were also noted. In his past history, he began to speak distinctly and to stagger since 8 years ago. Three years ago, he collided with guardrail while driving his motorcycle, and he was hospitalized. Calcification in the brain was already revealed in the roentogenographic examination. In the laboratory findings, the data of serum calcium, serum phosphorus and Ellsworth-Haward test were normal. The antibody of toxoplasma, however, showed high level more than X 1,024. After he was discharged, dementia, instability of trunk and dysarthria still continued, and he used to across a crowded road unconcernedly. The cause of the calcification might be suspected to be toxoplasmosis, although neither trophozoites, cysts nor oocysts were found in the brain tissue.

A simple differential immunoprecipitation assay of urinary acid and neutral alpha-glucosidases for glycogenosis II.

A specific assay for acid alpha-glucosidase in urine was developed to facilitate the diagnosis of glycogenosis II. This enzyme activity was calculated as a difference between the alpha-glucosidase activities before and after immunoprecipitation with antiserum to acid alpha-glucosidase. Acid alpha-glucosidase accounted for 86% of the total activity in control urine. All the cases of various clinical types of glycogenosis II showed either a marked decrease or a complete deficiency of this enzyme activity. A marked decrease of acid alpha-glucosidase was demonstrated by immunoblotting of the urine from patients with late-onset forms of this disease. These results indicate that assays of urinary acid alpha-glucosidase by this immunological method are useful for detection of the various types of glycogenosis II.