Clostridium difficile colitis associated with cisplatin-based chemotherapy in ovarian cancer patients

The purpose of this study was to examine the incidence and cause of Clostridium difficile colitis occurring after cisplatin-based combination chemotherapy in ovarian cancer patients. Thirty-three patients with primary ovarian malignancy were treated with cisplatin-based combination chemotherapy ranging from 1 to 12 (mean 4.6) cycles. All patients who developed diarrhea after undergoing the cancer chemotherapy were examined to determine whether or not they were complicated by C difficile colitis. The diagnosis of C. difficile was confirmed by a stool-cytotoxin test and endoscopic examination. Severe C. difficile colitis occurred in 2 patients (6.1%) after receiving cisplatin-based combination chemotherapy for ovarian malignancies. Although both patients recovered from the colitis after the administration of vancomycin, the first case demonstrated a relapse of the colitis after receiving a subsequent course of the same chemotherapy with cisplatin. Both patients were then treated with a carboplatin alternative to cisplatin in the following courses, which resulted in neither a relapse of the colitis nor a recurrence of the malignancies up to this time. This report suggests the importance of searching for the presence of C. difficile and its toxin in patients with diarrhea after undergoing cancer chemotherapy since C. difficile may cause severe colitis. Based on our findings, it is thus concluded that cisplatin may cause C. difficile colitis.

Characteristics of beta-adrenergic receptors in longitudinal muscle membranes of rat uterus: changes in kinetic properties of the receptor during gestation

Binding characteristics of beta-adrenergic receptors of longitudinal muscle membranes isolated from different stages of pregnant rat myometrium were investigated using [3H]dihydroalprenolol. Between Days 15 and 21 of gestation, the ratio of beta 1- and beta 2-adrenergic receptors of longitudinal membranes was constant. The membranes were found to be predominant in beta 2-adrenergic receptors. The concentration of longitudinal muscle beta-adrenergic receptors increased significantly during the last 7 days of gestation. Kinetic binding studies implied that the affinity of the membrane beta-adrenergic receptors decreased through a slight decrease in the association rate and a large increase in the dissociation rate with progression of pregnancy. A Scatchard plot indicated that longitudinal muscle in beta-adrenergic receptors on Days 15 and 18 constitute a single class of independent sites. By contrast, the dissociation kinetics, the convex downward curvature in a Scatchard plot and a Hill coefficient (h) of less than 1.00 of [3H] DHA binding to beta-receptors of muscle on Day 21 suggested the existence of negatively cooperative multiple binding sites for beta-adrenergic ligand. These results suggest that changes in the dynamics of uterus beta-adrenergic receptors play an important role in the onset of labor.

Accumulation of beta-amyloid fibrils in pancreas of transgenic mice

Some forms of familial Alzheimer's disease are caused by mutations in the amyloid beta protein precursor (beta APP), and there is excellent evidence that these mutations foster amyloid deposition by increasing secretion of total amyloid beta protein (A beta) or the highly amyloidogenic A beta 1-42 form. These observations provide a powerful rationale for developing an animal model of AD by generating transgenic mice in which cerebral amyloid deposition is induced by A beta overproduction. To produce substantial A beta in vivo, we generated mice expressing the transgene of signal peptide and 99 residues of carboxyl-terminal fragment (CTF) of beta APP under control of the cytomegalovirus enhancer/chicken beta-actin promoter. The transgenic mRNA was detected in many tissues of these mice, but the levels of transgenic mRNA, CTF, and A beta did not correlate well indicating that tissue-specific posttranslational processing may play an important role in determining the amount of A beta that accumulates in various tissues. A beta was detected biochemically in brain, kidney, and pancreas with the largest amount present in pancreas. In transgenic plasma, there was a marked accumulation of human A beta 1-40 and A beta 1-42(43) to levels over 30-times those observed in normal human plasma. Thus, the transgenic mice produce and secrete considerable A beta. Despite this increase in A beta secretion and the elevated A beta in brain, immunohistochemistry revealed no consistent cerebral A beta deposition. In pancreas, however, intracellular A beta deposits were detected immunohistochemically in acinar cells and interstitial macrophages, some of which showed severe degeneration. In addition, examination of these cells by immunoelectron microscopy revealed many putative amyloid fibrils (7-12 nm) that were stained by anti-A beta antibodies. Overall, our findings indicate that tissue-specific posttranslational processing may play a pivotal role in A beta production and amyloid fibril formation in vivo. By carefully analyzing the changes that occur in the transgenic mice described here as compared to the transgenic line that has recently been shown to form extracellular amyloid plaques in brain, it may be possible to gain considerable insight into the factors that determine the location and amount of A beta that accumulates as amyloid.

Hypertrophy of oxytocinergic magnocellular neurons in the hypothalamic supraoptic nucleus from gestation to lactation

In the present experiments, we examined the changes in cell size (profile area) of oxytocinergic magnocellular neurons during reproductive states and dehydration with quantitative immunohistochemistry. During lactation, hypertrophy was observed in oxytocinergic magnocellular neurons but not in vasopressinergic ones in the supraoptic nucleus. In virgin rats, chronic dehydration increased the cell size in both oxytocinergic and vasopressinergic neurons. After normal weaning time, the cell size decreased, returning to virgin level within 20 days. However, if the mothers were deprived of their litters immediately after parturition, the cell size rapidly returned to virgin level within 5 days. Furthermore, the increase in the cell size of the mothers was not affected by the size of their nursing litters.

Intracellular generation of amyloid beta-protein from amyloid beta-protein precursor fragment by direct cleavage with beta- and gamma-secretase

Two amyloid beta protein precursor (beta APP) fragments involving Met and 103 amino acids of C-terminus of beta APP (delta NOR-beta) and its KM-NL substitution (delta NL-beta) were expressed in COS-7 cells to clarify the proteolytic cleavages to generate amyloid beta protein (A beta). The 4.5-kD protein, A beta with additional N-terminal amino acids, and 4-kD A beta were directly produced and released from 12.5-kD expression proteins without any production of 11.4-kD C-terminal fragment starting at N-terminus of A beta and 3-kD "p3" A beta derivative. Intracellular 4-kD A beta was also detected. The substitution of KM-NL of beta APP found in Swedish familial Alzheimer's disease (AD) promoted the production of intracellular A beta and its release with no increase in level of 11.4-kD C-terminal fragment. These results suggested the presence of a distinct pathway in which A beta is directly cleaved at both N- and C-termini from beta APP fragment intracellularly to release A beta. Since KM-NL substitution enhanced intracellular A beta generation, this pathway may be associated with amyloidogenesis in AD.

Systemic overexpression of a C-terminal fragment of human amyloid beta-protein precursor causes accumulation of Alzheimer beta-amyloid fibrils in pancreas of transgenic mice

The deposition of amyloid beta-protein (A beta), derived from amyloid beta-protein precursor (beta APP), is a specific and early event in development of Alzheimer's disease. Transgenic mice carrying the carboxyl-terminus of beta APP gene linked to the cytomegalovirus enhancer/chicken beta-actin promoter sequence were studied. Deposition of amyloid fibrils, composing A beta, was observed in the transgenic pancreas, accompanied with cell degeneration. This result will provide a model to investigate the beta APP processing mechanism in vivo and a clue to generate possible A beta amyloidosis in animal brains.

Amyloid beta-protein ending at Thr43 is a minor component of some diffuse plaques in the Alzheimer's disease brain, but is not found in cerebrovascular amyloid

The distribution of amyloid beta-protein ending at 40 (A beta 40), 42 (A beta 42), and 43 (A beta 43) were immunocytochemically examined in Alzheimer's brains. A large number of diffuse plaques were stained with A beta 42 antibody (S42), but some were weakly labeled with A beta 43 antibody (S43). Immature and mature plaques were labeled with A beta 40 antibody (S40), S42, and S43. Thus, A beta 42 is the major component of diffuse plaques, the initial phase of plaque formation, and A beta 43 is present as a minor component. Only A beta 40 is present in cerebrovascular amyloid.

Fos expression in the hypothalamic magnocellular neurons of rats during pregnancy, parturition and lactation

Changes in Fos expression of magnocellular neurons in the supraoptic nucleus (SON) and the paraventricular nucleus (PVN) of the rat hypothalamus were investigated using immunohistochemistry during pregnancy, parturition and lactation. Quantitative morphometrical analysis revealed that Fos-positive cells in the hypothalamic magnocellular neurons were rarely seen in days 10 and 20 pregnant rats, however, significantly numerous Fos-positive cells were found in parturient rats. The number of Fos-positive cells was drastically decreased within a few days after parturition. Moreover, it was found using dual immunohistochemistry that the percentage of Fos-positive cells in vasopressin (AVP) magnocellular neurons of the SON was higher than that of the PVN in parturient rats, although oxytocin (OXT) magnocellular neurons showed the same percentage of Fos-positive cells between the SON and PVN. These results demonstrate that the hypothalamic magnocellular neurons express Fos during a limited period after parturition, and Fos expression in AVP magnocellular neurons is heterogeneous between the SON and PVN.

Modified amyloid beta protein ending at 42 or 40 with different solubility accumulates in the brain of Alzheimer's disease

Serial extraction study of Alzheimer's disease (AD) and control brains revealed 4, 3.7 and 3 kD amyloid beta protein (A beta) species accumulated in AD brains. In the fractions extracted with TBS, 10% SDS and formic acid, considerable amounts of A beta species were recovered in SDS fractions besides TBS and formic acid fractions. Immunoblotting with several site-specific antibodies confirmed not only the presence of 4 kD A beta starting at the first amino acid of A beta but also 2 smaller A beta species with modification of their amino-termini in the highly resolutional Tris/Tricine gel system. A beta solubility using these solvents was associated with both modification of the amino-terminus and length of carboxyl-terminus of A beta. Especially, a large amount of modified A beta was found to be accumulated as forms with different solubility in AD brains.

[Analysis of relationship between personality and emesis gravidarum in pregnant women]

The relationship between personality types and the symptoms of emesis gravidarum in pregnant women was analyzed by means of the Cattel personality test (revised by Nishizono) performed in early and mid pregnancy. Personality types were classified into five from cyclothymia A to schizothymia E. As for emesis, the patients were also classified into three groups, severe (35), mild (41) and none (19), according to the severity and duration of the symptoms. As a result, there was no significant difference between the types and the symptoms, but significant differences were seen in interpersonal attitudes, especially in sociality and dominative propensity, which were constituents of the personality type. The results of the analysis suggested that the patients who revealed disunification tended to express strong emesis as a somatic language. These results therefore indicate the necessity for counseling about personality without simply explaining it as their predisposing constitution, when we encounter strongly emetic pregnant women.

Changes in kinetic properties of oxytocin receptors in longitudinal muscle membranes of rat uterus during gestation

Receptors of oxytocin were found to occur in the membrane fraction obtained from longitudinal muscle of pregnant rat uterus. The affinity of the membrane receptor for oxytocin increased through an increase in the association rate and a decrease in the dissociation rate during gestation. The membrane oxytocin receptor concentrations rose almost three-fold from Day 15 to Day 21. A transition of oxytocin receptors from a single class of independent sites to site-site interacted multiple binding sites, which most likely exhibit positive cooperativity during the last seven days of gestation, was observed. These results suggest that changes in the dynamics of uterine oxytocin receptors also play an important role in the onset of labor.

[The prevention of cancer chemotherapy-induced emesis with granisetron and clonazepam]

The antiemetic efficacy of a combination of granisetron and clonazepam was investigated in 39 gynecological cancer patients treated with cisplatin. Granisetron (3 mg/body/day) was administered by intravenous drip infusion before and 24 hours after anticancer drug administration, and clonazepam was taken orally twice a day. With a combination of granisetron and clonazepam, excellent efficacy was found in 87% (34/39) of the cases. Delayed emesis occurred in 38% (13/34), but the degree of nausea was mild. Clinically, antiemetic therapy with a combination of granisetron and clonazepam demonstrated superior antiemetic effects and seems to be useful for controlling nausea and vomiting associated with cancer chemotherapy.

Role of the sodium-calcium exchange mechanism and the effect of magnesium on sodium-free and high-potassium contractures in pregnant human myometrium

OBJECTIVE

Periodic uterine relaxation in labor relieves the fetus from hypoxia related to sustained contractions. A reduction in intracellular calcium is essential for relaxation. Therefore we aimed to clarify the extrusion mechanisms of intracellular calcium ions in pregnant human myometrium.

STUDY DESIGN

Isometric contraction of small muscle bundles obtained from human myometrium at term was recorded. High-potassium and sodium-free solutions could induce stable contractures that revealed initial phasic contractions followed by tonic contractions. The effects of external calcium, external magnesium, nifedipine, and calcium adenosine triphosphatase inhibitors on both contractures were then examined.

RESULTS

Because maximum tonic contraction was induced by 48 mmol/L potassium, this concentration was used. Both contractures depended on external calcium concentrations. Nifedipine, 10(-7) mol/L inhibited both initial phasic contractions and the tonic phase of the high-potassium contracture; however, it could not suppress the tonic phase of the sodium-free contracture. Calcium adenosine triphosphatase inhibitors, cyclopiazonic acid and lauryl sulfate, potentiated the tensions of tonic phases in both contractures; the effect of lauryl sulfate was stronger than that of cyclopiazonic acid. When external magnesium was gradually increased (from 0 to 9.6 mmol/L), both phasic contractions and the tonic phase of the high-potassium contracture transiently increased, followed by a reduction of tension, whereas the tonic phase of the sodium-free contracture was markedly inhibited by magnesium in a dose-dependent manner.

CONCLUSION

The presence of the sodium-calcium exchange mechanism and the specific inhibitory effect of magnesium were indicated in human myometrium during pregnancy. These mechanisms might prevent the long tonic contractions, to protect the fetus from hypoxia during pregnancy and parturition.

Maintenance of ultrastructural plasticity of the hypothalamic supraoptic nucleus in the ovariectomized rat

In the present experiments, we examined the effect of ovariectomy on the increases in litter weight and structural plasticity of MNCs in the supraoptic nucleus (SON) during lactation. Female rats were ovariectomized 2 days after parturition, and the increases in litter weight were measured as the index of milk let-down from dams during lactation. The lactation period was elongated up to 6 weeks by providing new litter to obtain more apparent effects of the ovariectomy. There was no significant difference in the increases in litter weight between non-operated and ovariectomized females. After lactation for 6 weeks, the ultrastructures such as juxtaposition (surface membrane apposition) and multiple synapses (terminals contacting with two or more postsynaptic elements) of MNCs in the SON in nonoperated and ovariectomized females were examined to compare with those of virgins. The percentage of juxtaposition and the number of multiple synapses significantly increased in nonoperated lactating females as compared with those of virgins. Ovariectomized rats showed similar structural changes to those of nonoperated females during lactation. Therefore, we conclude that ultrastructural plasticity of MNCs in the SON is maintained even in the absence of an ovary, and direct or indirect actions of suckling stimulation may be important in maintaining the plasticity during lactation.

Effect of prolonged beta-adrenergic blockade induced by atenolol on left ventricular remodeling after acute myocardial infarction in the rat

Beta-adrenergic receptor blockade reduces the mortality rate after acute myocardial infarction (AMI) in humans. However, the effects of beta blockade on left ventricular remodeling remain unknown. Therefore, in the present study we investigated the effect of prolonged beta-adrenergic receptor blockade with atenolol on left ventricular remodeling following AMI in rats. Myocardial infarction (MI) was produced in Wistar-Kyoto rats by ligating the coronary artery. Four groups of rats were studied: sham-operated (n = 10); atenolol (1 g/l in drinking water) treated sham-operated (n = 8); untreated MI (n = 11); atenolol treated MI (n = 10). Hemodynamic measurements were made about 3 weeks after the operation. Infarct size was similar in treated and untreated MI rats (31.2 +/- 2.5% cf. 33.5 +/- 2.0%). MI rats were characterized by increases in left ventricular end-diastolic pressure (LVEDP), right atrial pressure (RAP), right ventricular systolic pressure (RVSP), and left ventricular end-diastolic volume index (LVEDVI), as compared with sham-operated rats. In sham-operated rats, prolonged beta-adrenergic receptor blockade produced only a reduced HR. Atenolol-treated MI rats had a significantly higher LVEDP, RAP and LVEDVI than did rats with untreated MI. Prolonged beta-adrenergic receptor blockade with atenolol appeared to promote left ventricular remodeling after AMI. Thus, the treatment of AMI with beta-adrenergic receptor blockade in the clinical setting should be evaluated with respect to ventricular remodeling during prolonged therapy.

Primary osteosarcoma of the uterus: report of a case with immunohistochemical analysis

Primary osteosarcoma of the uterus is an extremely rare neoplasm, and its immunohistochemical characteristic is unknown. We report a case of osteosarcoma occurring primarily in the uterine corpus of a 67-year-old woman with lower abdominal pain. The excised tumor showed bony inconsistency and histologically displayed a "pure" osteosarcoma of the uterus. Immunocytochemically, the tumor cells were positive for vimentin but negative for epithelial markers. The patient died 4 months after surgery because of developed local recurrence and pulmonary metastases. In conclusion, uterine osteosarcoma differs from malignant mixed Müllerian tumor (MMMT) in biological behavior, macroscopic and histologic features, and immunohistochemical profile. Osteosarcoma shows more aggressive behavior than MMMT, and displays nonpolypoid feature in appearance and no evidence of epithelial differentiation.

Presence of apolipoprotein E on extracellular neurofibrillary tangles and on meningeal blood vessels precedes the Alzheimer beta-amyloid deposition

The localization of apolipoprotein E (ApoE) has been examined immunohistochemically in the autopsied brains of middle-aged and old-aged control subjects, with and without amyloid beta protein (A beta) deposits, and of Alzheimer's disease patients. Senile plaques were consistently labeled with ApoE antiserum even in the very early stage of senile plaque formation seen in the fifth decade. In the cerebellar molecular layer, small dots of ApoE immunoreactivity, which were prominent in the Alzheimer's disease subjects, were observed in addition to immunoreactivity in diffuse plaques. ApoE antisera labeled all of the extracellular neurofibrillary tangles (NFT), whereas only a small minority of extracellular NFT were positive for A beta. A punctate pattern of ApoE immunoreactivity was seen at the media of the meningeal vessels lacking amyloid, when senile plaques were present in the nearby cortex. In the early stage of amyloid angiopathy, the distribution of ApoE immunoreactivity was much more extensive than that of A beta positivity. These findings suggest that ApoE accumulates in the early stage of senile plaque formation and, furthermore, that ApoE accumulation precedes A beta deposition in extracellular NFT and amyloid angiopathy.

Localization of Alzheimer amyloid beta protein precursor and its relation to senile plaque amyloid

The authors examined the ultrastructural localization of amyloid beta protein precursor (APP) in normal human brains immunohistochemically using 3 kinds of APP antisera. The patterns of immunoreaction differed between the antisera used. Antiserum 770, against APP1-770, predominantly labeled the cytoplasm of neurons, whereas antiserum Z31, against the pre-beta region of the APP, labeled astroglial processes intensely and neurons to a lesser extent. Antiserum 1736, against the N terminal of beta protein, labeled both neurons and astrocytes. Vascular smooth muscle cells and some of the endothelial cells in the cerebral arterioles and capillaries were labeled with Z31 and 1736. The APP exists in every cells, while various patterns of immunoreactivity may reflect the difference in the metabolic pathway of APP between cell types.

Ultrastructural localization of amyloid beta/A4 protein precursor in the normal rat brain

The ultrastructural localization of amyloid beta/A4 protein precursor (APP) was studied immunohistochemically in normal rat brains using antibodies against different portions of APP. In cerebral cortical neurons and Purkinje cells. APP reaction products were located in the cytoplasm and on cell surface membranes. Some Golgi apparatuses and rough endoplasmic reticulum also showed APP immunoreactivity on their membranes and some vesicles near the trans face of the Golgi apparatuses were stained. In the neuropil of the cerebral cortex and the cerebellar molecular layer, many cell processes, which surrounded synapses and were considered to be astrocytic, were APP-positive. Foot processes around capillaries and subpial astrocytic processes were also immuno-positive. At the ultrastructural level, APP-positive astrocytic processes were identified.

Differential expression of alpha 1-antichymotrypsin in the aged human brain

The localization of alpha 1-antichymotrypsin (ACT) mRNA and ACT immunoreactivity (ACT-IR) were examined in 12 brains obtained at post-mortem from elderly patients, four of whom had Alzheimer's disease. A biotinylated oligonucleotide probe was used for in situ hybridization histochemistry and the relationship between the expression of both ACT mRNA and ACT-IR and the extent of beta protein or tau deposition were investigated. The extent of beta-plaques, tau-tangles, and ACT-IR were rated from (-) to (++). In brains without plaques and tangles, there were no detectable ACT mRNA signals in the gray matter, and those in the white matter were weak; in these brains, ACT-IR was generally weak. The brains with beta-plaques but no tangles showed weak ACT mRNA expression in astrocytes of both the gray and white matter; they also showed weak ACT-IR in the astrocytes. In the brains from patients with Alzheimer's disease with both plaques and tangles, ACT mRNA was expressed intensely in a majority of the astrocytes in the white and gray matter. Some senile plaques-associated astrocytes expressed ACT mRNA and ACT-IR was strong in the white matter astrocytes. ACT-IR and ACT mRNA expression in astrocytes was correlated with the extent of beta and tau depositions.

Serial changes in atrial and brain natriuretic peptides in patients with acute myocardial infarction treated with early coronary angioplasty

To examine the role of brain natriuretic peptide (BNP) in acute myocardial infarction (AMI), we measured the plasma concentration of immunoreactive (ir) BNP together with that of atrial natriuretic peptide (ANP) over the 4-week course of AMI in 16 patients treated with early coronary angioplasty. Both the plasma ir-ANP and ir-BNP levels were increased on the first day of the infarction compared with the values in normal subjects. During the clinical course of the infarction, the plasma ir-ANP concentration soon decreased, while the plasma ir-BNP level remained elevated at 2 weeks after the infarction, also exhibiting a high level at 4 weeks. Plasma ir-BNP levels on day 1 or days 14 and 28 were inversely correlated with left ventricular ejection fraction obtained by left ventriculography at the acute or chronic phase, respectively. Plasma ir-BNP concentrations on days 14 and 28 were positively correlated with the maximal myosin light chain I level, an indicator of infarct size. These observations suggest that the plasma ir-BNP level increased to compensate for the ventricular dysfunction associated with the size of the infarct in AMI. BNP may act as a cardiac hormone in AMI, differing somewhat from ANP in its synthetic, secretory, or clearance behavior.

Amyloid beta protein precursor accumulates in swollen neurites throughout rat brain with aging

We immunocytochemically studied the expression of amyloid beta protein precursor (APP) in the brains of normal aged rats, and found APP accumulation in swollen neurites, most of which were axons. These swollen neurites appeared throughout the central nervous system of aged rats; most of them were negative for neurofilament, ubiquitin, and tau. Such widely distributed APP accumulation in swollen neurites may reflect impaired fast axonal transport due to aging. APP immunostaining may be a good method to detect widely distributed age-related changes.

Oxytocin modulates oxytocin neurons in the paraventricular nuclei of female rats throughout pregnancy and parturition

OBJECTIVE

The physiologic roles of nonphasic firing oxytocin neurons in the paraventricular nucleus of female rats throughout pregnancy and parturition was studied from the viewpoint of changes in the membrane activities.

STUDY DESIGN

Thin colonal hypothalamic slices containing the paraventricular nucleus were prepared. Immunohistochemical studies of oxytocin in the paraventricular nucleus were performed to determine the localization of oxytocin-containing neurons. Extracellular single neural activities were recorded with a glass micropipette from the oxytocin-dense area, and physiologic concentrations of oxytocin were applied.

RESULTS

Nonphasic firing activity was recorded from 61 neurons in virgin female, pregnant, delivering and lactating rats. After bath application of < 5.0 x 10(-11) mol/L of oxytocin, firing rates of 12 of 17 paraventricular neurons in virgin rats decreased and only one increased, whereas the remaining four showed no response to oxytocin. In pregnancy at day 15 all four neurons decreased in activity, whereas at day 21 rats 20 of 26 neurons decreased, two increased, and four showed no response. On the contrary, in delivering rats seven of eight neurons exhibited excitatory responses, and only one showed no response. This excitation reversed to inhibition again after the lactating period ended.

CONCLUSION

Negative feedback by oxytocin in virgin and pregnant rats might reverse to positive feedback in delivering and lactating animals as a result of changes in hormonal conditions. This reverse might be closely related to the initiation of delivery.

Diagnostic significance of skin immunolabelling with antibody against native cerebral amyloid in Alzheimer's disease

Skin taken from patients with Alzheimer's disease (AD) and control patient groups were immunolabelled using antisera against either purified native cerebral beta protein or synthetic beta peptide. Native amyloid antiserum frequently labelled vascular walls in AD skin but rarely in control skin. Semi-quantitative analysis of the positive vessels showed a significant difference between the two groups. Sweat glands and dermal nerves were labelled in both groups. However, synthetic beta peptide antiserum showed no significant difference. Vascular wall labelling in skin with native amyloid antiserum is useful in the differential diagnosis of AD.

Changes in beta-adrenergic receptors under long-term application of ritodrine in pregnant-rat myometrium

Changes in beta-adrenergic receptor density under long-term application of ritodrine were investigated using longitudinal muscle strips of day-21-pregnant-rat myometrium. Membrane (-)[3H]dihydroalprenolol binding sites were increased by 3.1 x 10(-8) M ritodrine, with a maximum increase at 3.1 x 10(-7) M, followed by a gradual decrease at higher concentrations. Under long-term application of a lower dose (1.5 x 10(-7) M) of ritodrine, the number of the binding sites increased up to 20 min, then decreased to the control level and fluctuated after 90 min. These results suggest that at lower doses, ritodrine might activate adenylate cyclase, resulting in conformational changes in the receptors, and that receptor density might vary in parallel with cellular cAMP production under long-term application of ritodrine.

Oxytocin inhibits nonphasically firing supraoptic and paraventricular neurons in the virgin female rat

Nonphasically firing activities were recorded from neurons in the supraoptic (s.o.) and paraventricular (p.v.) nucleus of the virgin female, male, and ovariectomized rat hypothalamic slice preparations. Following bath application of oxytocin (OXT), less than 1.0 x 10(-8) M, 24 (75%) of 32 virgin female s.o. neurons showed inhibitory responses and only one neuron showed excitatory response. In contrast to virgin female, five (63%) of eight male s.o. neurons were excited by OXT application. The same tendency was shown in the p.v. neurons. Among six s.o. neurons obtained from ovariectomized virgin rats, five neurons increased their firing rate to the application of OXT. After blocking synaptic transmission, the inhibitory responses of virgin s.o. neurons and the excitatory responses of ovariectomized virgin s.o. neurons to application of OXT were still observed with equal configurations. These findings suggest that the responses of nonphasic neurons to OXT may not due to synaptic drives.

Ultrastructural characterization of cerebellar diffuse plaques in Alzheimer's disease

We examined the ultrastructural localization of beta/A4 protein in cerebellar diffuse plaques (DP) in three Alzheimer's disease brains by the indirect immunoperoxidase technique. Intense immunoreaction products were scattered in the DP; they were strongly suggested to be located between small cell processes. Reaction products were dot-like and/or amorphous, and occasionally fibrillar. Adjacent semithin sections of regions immunoreactive for beta/A4 protein revealed only very small amounts of amyloid fibrils between cell processes and/or small numbers of degenerating neurites. The small degenerating neurites which appeared in most DP lacked paired helical filaments (PHF) and neurofilaments (NF). These findings suggest that the majority of the beta/A4-immunoreactive substance in cerebellar DP is non-fibrillar pre-amyloid found between cell processes and barely detectable by routine electron microscopy.

Expression of APP in the early stage of brain damage

We immunocytochemically studied the expression of various epitopes of amyloid beta/A4 protein precursor (APP) after brain damage by kainic acid injection. After 3 h, APP695 rapidly accumulated in dystrophic neurites near the damaged site. After 3 days, APP with Kunitz-type protease inhibitor domain was expressed in reactive astrocytes in the lesion and ipsilateral hippocampus. APP rapidly accumulated in dystrophic neurites, and different types of APP were expressed in different cell types in the damaged brain.

Qualitative evaluation of uterine contractions recorded by a double guard-ring tocodynamometer

Qualitative characteristics of uterine contractions in various labors were evaluated by a double guard-ring tocodynamometer, according to the percentages of concurrent and synchronous contractions of two contraction curves when compared with overall contractile activity. For term and preterm labors, percentages of both concurrent and synchronous contractions were significantly higher than those of Braxton Hicks contractions; however, the concurrent and synchronous percentages of preterm labor were lower than those of term labor. Synchronous percentage in groups under maintenance therapy or active treatment in preterm labor were nearly the same; however, the percent concurrent under maintenance therapy was significantly lower than that during active treatment. Both concurrent and synchronous percentages were significantly higher during the active phase of labor than those during the latent phase. The percentages in the latent and active phases of spontaneous contractions were nearly the same; however, they increased significantly during the active phase of augmented contractions, as compared with the latent phase. When the percentages of concurrent and synchronous contractions at each cervical dilatation were retrospectively examined, both values increased significantly between 5 and 6 cm of cervical dilatation. The results suggest that this method can provide important information for understanding the quality of the contraction if attention is paid to the percentages of concurrent and synchronous contractions of two contraction curves and will aid in determining whether oxytocin or tocolysis should be given in term or preterm labor.

Intracellular calcium of longitudinal muscles isolated from pregnant rat myometrium

Longitudinal muscle cells were successfully isolated from pregnant rat myometrium (21 days of gestation) with more than a 95% survival rate. The approximate size of relaxed cells was 232.2 +/- 74 microns in length and 16.2 +/- 7.0 microns in width. Using the fluorescent indicator Fura-2, the concentration of intracellular free calcium ([Ca2+]i) in resting state cells was calculated to be 116 +/- 18.5 nM. The isolated cells responded well to K+, acetylcholine and oxytocin in terms of contraction as well as the increase in [Ca2+]i. The increase in [Ca2+]i induced by acetylcholine and K+ appeared to be mainly due to an influx of extracellular Ca2+. On the other hand, the oxytocin-induced increase in [Ca2+]i was mainly due to a release of Ca2+ from intracellular storage sites in the isolated cells. Isolated longitudinal muscle cells can serve as a useful tool in establishing the relationship between [Ca2+]i and regulation of the uterine contraction at the final stage of pregnancy.

Amyloid beta/A4 protein precursor is widely distributed in both the central and peripheral nervous systems of the mouse

We studied the immunocytochemical distribution of amyloid beta/A 4 protein precursor (APP) in both the central and peripheral nervous tissues of the mouse. We used two different antisera against the synthetic peptides corresponding to the carboxyl- and the amino-terminal regions of APP, which are common to all isoforms of APP (APP695, APP714, APP751 and APP770). Both antisera recognized the same 106-122 kDa proteins from the mouse brain on immunoblotting. Immunocytochemically, in cortical and subcortical areas, reactivities of both antisera were located in neurons of all sizes. Immunoreactive neurons were widely distributed showing no particular pattern. Various neuron types in the spinal cord were also immunoreactive. In the peripheral nervous system, ganglion cells and their processes showed immunostaining. Immunoreactivity was also seen in the astrocytes, oligodendroglia and ependymal cells widely distributed in the brain and spinal cord, mantle cells in the ganglia, and Schwann cells in peripheral nerves. These results indicated that the full length of APP is distributed in almost all neurons and some glial cells in the mouse central and peripheral nervous systems.

Colposcopic assessment of stage I cervical cancer

A differential assessment by colposcopy of three subgroups of stage I in the new FIGO classification of cervical cancer was attempted. Colposcopic findings in invasive cancer were atypical white epithelium, atypical mosaic, papillary punctation, atypical vessels, abnormal ‘rock-like’ projection, papillomatous growth and ulcer. Ulcer and abnormal ‘rock-like’ projection were more suggestive of a frank invasive carcinoma than a microinvasive carcinoma. While 89% of the cases in stage Ib were correctly predicted, only about 50% of those in stage Ia were correctly predicted. We propose that a colposcopic assessment be included in the armamentarium to decide the method of treatment for cervical cancer patients.

Extracellular neurofibrillary tangles associated with degenerating neurites and neuropil threads in Alzheimer-type dementia

We examined the cellular components of extracellular neurofibrillary tangles (E-NFT) in the hippocampal areas in cases with Alzheimer-type dementia. Immunohistochemically, the E-NFT were labeled for the C terminus of tau and glial fibrillary acidic protein. Moreover, the majority of the E-NFT was associated with intensely argyrophilic rods and with tau- and ubiquitin-immunoreactive dots. Ultrastructurally, the E-NFT consisted mainly of extracellular paired helical filaments (PHF) and astroglial processes. The extracellular PHF tended to be straighter and thinner. One third of the E-NFT was associated with small degenerating neurites containing many dense bodies and with neuropil threads containing PHF. These findings suggested that extracellular PHF promote both intense astroglial reaction and neuritic alteration, and that the E-NFT are continuously changing their morphology.

Light and electron microscopic and immunohistochemical observations of the Onuf's nucleus of amyotrophic lateral sclerosis

We examined the Onufrowicz nucleus (Onuf's nucleus) of ten sporadic amyotrophic lateral sclerosis (ALS) patients with light and electron microscopic and immunohistochemical methods. Neurons in the Onuf's nucleus of ALS patients were better preserved than those in anterior horn cells. However, some showed morphological changes in the nucleus, namely, central chromatolytic changes, Bunina bodies, ubiquitin-positive filaments and spheroids. The Onuf's neurons of ALS patients showed more argentophilia than those of non-ALS patients. Electron microscopic observations revealed that neurofilaments were relatively more numerous in the Onuf's neurons of ALS patients. Bunina bodies and degenerated neurites were also seen in the Onuf's nucleus. In conclusion, the Onuf's nucleus in sporadic ALS patients showed some morphological changes similar to those noted in anterior horn cells.

Subpial beta/A4 amyloid deposition occurs between astroglial processes in Alzheimer-type dementia

We examined the ultrastructure of subpial beta/A4 amyloid deposits in the brains of patients with Alzheimer-type dementia. A few amyloid fibrils were found between thick astroglial processes (glia limitans). We also examined the ultrastructural localization of beta/A4 protein by the indirect immunoperoxidase technique. Electron-dense immunoreactive products scattered sporadically in the subpial areas were observed between astroglial processes. The labeling was fibrillar and/or amorphous. Subpial beta/A4 deposition may occur between astroglial processes as amorphous pre-amyloid and amyloid fibrils.

Pheochromocytoma with electrocardiographic change mimicking angina pectoris, and cyclic change in direct arterial pressure--a case report

A forty-two-year-old man was admitted because of chest pain. Electrocardiograms at admission showed horizontal ST depression in leads, II, III, aVF, V4, V5, and V6. Direct blood pressure monitoring revealed cyclic change between 160/100 mmHg and 70/50 mmHg and heart rate between 80/sec and 120/sec at fifteen minute intervals. The plasma norepinephrine and epinephrine concentrations were elevated during the episodes of hypertension. Pheochromocytoma was found in the right adrenal gland. These cyclic changes in blood pressure and heart rate are an aid for diagnosis.

Relationship between changes in contraction and cyclic AMP contents under long-term application of ritodrine in pregnant rat myometrium

The relationship between contraction changes and cAMP production under long-term application of ritodrine was investigated using longitudinal muscle strips of pregnant (Day 21) rat uterus. Cellular cAMP gradually increased up to 20 min, then decreased to the control level and fluctuated after 90 min in the presence of 1.5 x 10(-7) M ritodrine. When the dose was raised to 3.1 x 10(-4) M, cAMP contents markedly increased. However, it then decreased after 30 min and reached the control level after 180 min. To clarify the actual relationship between the changes in spontaneous contraction and cAMP contents of the same muscle strips, the strips were obtained during control contraction, suppression by 1.5 x 10(-7) M ritodrine and reactivation after suppression in the presence of the drug. Consequently, the cAMP content of reactivated muscle was significantly lower than that of suppressed muscle (p less than 0.01), however it was still higher than the control (p less than 0.05). It is speculated that the reactivation of spontaneous contractions might not depend solely on the cellular cAMP level, and that another activating mechanism, such as changes in ion permeability, might be involved in this type of desensitization phenomenon.

Alzheimer amyloid beta-protein precursor in sperm development

We prepared antisera to both the N and C termini of amyloid beta-protein precursor (APP). Both antisera labeled 110 to 140 kd proteins from rat testis by immunoblotting. Northern blot analysis using oligonucleotide probes complementary to respective APPs showed that APPs expressed in rat testis contained Kunitz-type protease inhibitor domains. Immunocytochemically brain APP was localized in neurons and their processes. During sperm formation, APPs labeled by both antisera were localized only in acrosome and the growing tail of spermatids in the seminiferous tubules. This shows that APPs appear only in particular phases of spermatogenesis, that is, in the morphologic change phase from spermatid to mature sperm. Amyloid beta-protein precursors in testis may play a role in cellular differentiation or morphologic change.

The amyloid beta-protein precursor is localized in smooth muscle cells of leptomeningeal vessels

We examined leptomeningeal vessels using 2 different antisera which recognized both terminal ends of amyloid beta-protein precursor (APP). Both antisera recognized a 120-kDa protein from leptomeningeal vessels. Immunocytochemistry showed that APP was localized in the smooth muscle cells of leptomeningeal vessels. These results indicated that the smooth muscle cells of leptomeningeal vessels contained full-length native APP, and that the cerebrovascular amyloid in the leptomeningeal vessels was derived from this APP.

Modification by magnesium of the excitatory effect of oxytocin in electrical and mechanical activities of pregnant human myometrium

The modification by magnesium of the excitatory effect of oxytocin (10(-5)-10(-2) U/mL) on electrical and mechanical activities of pregnant human myometrium was examined. The excitatory effect of oxytocin was enhanced by external magnesium, and the dose-response curve between oxytocin and relative tension in the presence of 118 mM potassium in tiny muscle strips shifted to the left with increases in magnesium from 0 to 2.4 mM. Oxytocin potentiates spontaneous contractions by enhancing the plateau part of action potentials, and the plateau potential induced in 2.4-mM magnesium was larger than that in magnesium-free solution. In potassium contracture experiments, the muscle contraction was potentiated in accordance with the concentration of preloaded magnesium when 10(-3) U/mL oxytocin was added at the tonic phase. These results suggest that magnesium might primarily potentiate the excitatory effect of oxytocin in electrical and mechanical activities of pregnant human myometrium at superficial sites of the plasma membrane, allowing the possibility of its intracellular action.

Clinical features of long contraction wave recorded by an external tocodynamometer

Clinical features of a long contraction wave, lasting 3 minutes or more, recorded on an external tocodynamometer were studied. The long wave was observed in 50 out of 1,050 pregnant women. Clinical significance was not indicated by the shape of each wave which was either a long relaxing type or a fused type, but by the frequency of occurrence. Vaginal delivery and its close relation to oxytocin administration were significantly more frequent in the sporadic type, in which the long wave was observed once within a week, and fetal distress and a low Apgar score were more frequently observed in the frequent type, in which long waves occurred twice or more within a week. The results suggest that the obstetric prognosis is normal unless the long wave occurs sporadically and its recovery is good, and that it is ominous when long waves are observed twice or more within a week. Careful observation is needed in that case.