Removal of carbon contamination in ETEM by introducing Ar during electron beam irradiation.

Organic materials, including carbon, exist inside the transmission electron microscope (TEM) chamber and are adsorbed onto samples under observation during TEM. When these adsorbed organic materials are irradiated by an electron beam, the adsorbed gas is decomposed. Carbon atoms remain on the sample and bond with each other forming a material with an amorphous structure. Due to the carbon deposition on the observation area of the sample, it is contaminated and the TEM image quality is decreased. Ar was introduced into environmental TEM (ETEM) to purge organic material from the sample chamber to reduce contamination growth. After Ar gas was introduced, the contamination was gradually removed. The contamination removal rate was dependent on the Ar pressure. Moreover, it was clear that Ar was ionised by electron beam irradiation and the Ar ions were produced in the ETEM during electron beam irradiation. It is proposed that the Ar ions removed the carbon contamination. LAY DESCRIPTION: Organic materials, including carbon, exist inside the transmission electron microscope (TEM) chamber and are adsorbed onto samples under observation during TEM. When these adsorbed organic materials are irradiated by an electron beam, the adsorbed gas is decomposed. Carbon atoms remain on the sample and bond with each other forming a material with an amorphous structure. Due to the carbon deposition on the observation area of the sample, it is contaminated and the TEM image quality is decreased. Ar was introduced into environmental TEM (ETEM) to purge organic material from the sample chamber to reduce contamination growth. After Ar gas was introduced, the contamination was gradually removed. The contamination removal rate was dependent on the Ar pressure. Moreover, it was clear that Ar was ionised by electron beam irradiation and the Ar ions were produced in the ETEM during electron beam irradiation. It is proposed that the Ar ions removed the carbon contamination.

ADAMTS-1 is involved in normal follicular development, ovulatory process and organization of the medullary vascular network in the ovary.

To clarify the role of disintegrin-like and metalloproteinase with thrombospondin type I motifs-1 (ADAMTS-1) in ovarian function, we examined abnormalities in ovulatory processes, folliculogenesis and the vascular system of ADAMTS-1 null ovaries. First, when immature female mice were treated with pregnant mare serum gonadotropin (PMSG)/human chorionic gonadotropin (hCG), the number of ovulated oocytes was markedly decreased in ADAMTS-1 null mice in comparison to ADAMTS-1 (+/-) controls. The proportion of anovulated follicles to total mature follicles was significantly higher in ADAMTS-1 null females when compared with controls. The numbers of growing follicles at each stage were counted. The number of follicles at type 5b (late preantral) and later stages was markedly reduced in ADAMTS-1 null mice, irrespective of gonadotropin treatment (no gonadotropins, PMSG alone or PMSG/hCG). These data demonstrate that impairment of ovarian function to ovulate oocytes in ADAMTS-1 null mice occurs at two different levels: in the development of growing follicles and ovulatory processes. Furthermore, ADAMTS-1 null ovaries included a number of unusual atretic follicles that showed no sign of oocyte degeneration but lost the surrounding granulosa cell layers and were considered to be derived from type 4 or 5a follicles. These results suggest that ADAMTS-1 is important for follicular development beyond the type 4 and/or 5a and for maintaining normal granulosa cell layers in follicles. Finally, the number of large blood vessels in the medullar zone was significantly decreased in ADAMTS-1 null mice ovaries, suggesting that ADAMTS-1 is also involved in the organization of the medullary vascular network.

Electroencephalographic aspects of periventricular hemorrhagic infarction in preterm infants.

The aim of this study was to investigate electroencephalographic aspects of periventricular hemorrhagic infarction (PVHI) in preterm infants. The subjects were 11 preterm infants with PVHI, who were admitted to the Neonatal Intensive Care Unit of Anjo Kosei Hospital from April 1985 through December 1997. The patients underwent serial cranial ultrasonography and were diagnosed as having PVHI. An EEG was recorded at least once within 1 week after PVHI and then recorded at 1- to 4-week intervals until 40 weeks of postconceptional age. The EEG findings were classified into acute and chronic stage abnormalities. Acute stage EEG abnormalities were seen in 5 infants after PVHI, which were symmetrical in all infants. Among them, 3 infants died during the early neonatal period. The infants who had a higher grade of acute stage EEG abnormalities showed significantly higher mortality. Among the surviving 8 infants, chronic stage EEG abnormalities were seen in 3 predominantly in the ipsilateral side of PVHI, and all of them developed hemiplegia. The sensitivity and specificity of chronic stage EEG abnormalities to predict outcome were 0.75 and 1.0, respectively. Acute and chronic stage EEG abnormalities give valuable information for short-term and long-term outcome in preterm infants with PVHI.

Prognostic value of EEG depression in preterm infants for later development of cerebral palsy.

The aim of this study is to examine the most appropriate timing for EEG recordings in order to predict the risk of cerebral palsy (CP) on the basis of the degree of acute stage abnormalities (ASA) in preterm infants. We retrospectively investigated the correlation between the degree of ASA and psychomotor outcome of 295 infants born between 27 and 32 weeks of gestational age whose initial EEG recording was performed within 7 days of life. Forty-six infants were diagnosed as having CP at 18 months of corrected age, and most of them suffered from diplegia due to periventricular leukomalacia (PVL). The maximum degree of ASA correlated with a later development of CP and its severity. Correlation between the degree of ASA and the severity of CP was highest on day 1 - 2, but this tendency was less clear after day 3. Specificity and negative predictive value were generally high within the first 7 days of life. But sensitivity was markedly decreased after day 3, and positive predictive value was highest on day 2. An EEG on day 1 or 2 will be useful in order to predict developmental outcome of preterm infants on the basis of the grade of ASA.

Physical condition of preterm infants with periventricular leukomalacia.

The aim of this study is to determine the general condition of preterm infants with severe brain lesions and to compare it with that of normal preterm infants. The Score for Neonatal Acute Physiology (SNAP) was calculated in nine preterm infants with periventricular leukomalacia (PVL) whose initial electroencephalograms showed grade IV depression (PVL group), 18 preterm infants who did not require mechanical ventilation during the neonatal period, Spontaneous respiration (SR group), and 18 preterm infants who required mechanical ventilation (MV group). The sum of the following four items in SNAP was separately calculated and called the 'lung score': PaO(2), PaO(2)/FiO(2) ratio, PaCO(2), and oxygenation index. In addition to SNAP, we evaluated some neonatal variables. SNAP is lower in the SR group than in the PVL (P<0.05) or MV (P<0.01) groups. The lung score was also lower in the SR group than in the PVL (P<0.05) or MV (P<0.01) groups. On the other hand, the residual score (SNAP minus lung score) was not significantly different among the three groups. The physical condition of infants with PVL was not poor, although respiratory distress was often observed.

Relation between the date of cyst formation observable on ultrasonography and the timing of injury determined by serial electroencephalography in preterm infants with periventricular leukomalacia.

The aim of this study was to clarify the relation between the date of cyst formation and the timing of injury in preterm infants with periventricular leukomalacia in order to address the issue of whether or not we can determine the timing of injury on the basis of ultrasonographic findings. We studied 33 preterm infants with cystic periventricular leukomalacia, the gestational ages being 32 weeks or less. As 27 of them exhibited either acute or chronic stage abnormalities in the initial electroencephalogram, the timing of injury was presumed to be before or around birth. For the remaining six infants, the timing of injury was considered to be postnatal in two infants, and was not determined in another four. The median date of cyst formation was 18 days of age (range, 10-39 days) in the 27 infants with abnormal initial electroencephalograms. For these 27 infants, the gestational age did not influence the date of cyst formation. In contrast, the date of cyst formation was significantly earlier in infants with widespread cysts than in those with localized cysts. In conclusion, it is difficult to determine the timing of injury from ultrasonographic findings, because the range of the date of cyst formation on ultrasonography was very wide among infants whose timing of injury was not greatly different.

Cycloprodigiosin hydrochloride, a H+/Cl- symporter, induces apoptosis in human colon cancer cell lines in vitro.

Recently, we reported that cycloprodigiosin hydrochloride (cPrG.HCl), a novel H+/Cl- symporter, induces acidification of the cytosol and leads to apoptosis on rat and human liver cancer cells. In the present study, the effects of cPrG.HCl, a H+/Cl- symporter, were examined in colon cancer cell lines in vitro. In the MTT assay, cPrG.HCl inhibited the growth of two colon cancer cell lines (WiDr and SW480) in a dose- and time-dependent manner. The cPrG.HCl treatment of both types of cells induced apoptosis as confirmed by the appearance of a sub-G1 population and intranucleosomal DNA fragmentation. In addition, cPrG.HCl lowered pHi (below pH 6.8) respectively. Therefore, these results suggest that cPrG.HCl may be useful for the treatment of colon cancer cells.

Five-year follow-up of patients with partial epilepsies in infancy.

The aim of this study is to clarify the long-term outcome of patients with partial epilepsies that begin in the first 2 years of age. Thirty-nine infants who experienced partial epilepsies with onset by 2 years of age were followed until they were at least 5 years of age. Seizure and developmental outcome were investigated in relation to the following items: delayed psychomotor development before onset of seizures; interictal electroencephalogram (EEG) abnormalities; abnormal neuroimaging; family history of epilepsy; and history of neonatal seizures. Thirty-three infants achieved freedom from seizures and 27 achieved normal development. Delayed development before the onset and abnormal interictal EEG correlated with both poor seizure and developmental outcome. Abnormal neuroimaging findings correlated with a poor seizure outcome. A history of neonatal seizures and lack of a family history of epilepsy correlated with poor developmental outcome. The combination of the first four factors predicted a normal outcome with a sensitivity of 0.79 and a specificity of 0.87. The seizure and developmental outcomes were better in this study than those in previous studies. The combination of the four factors will be useful for predicting the outcomes in patients with partial epilepsies in infancy.

Hypocarbia in preterm infants with periventricular leukomalacia: the relation between hypocarbia and mechanical ventilation.

OBJECTIVE: The aim of this study was to elucidate the relationship between mechanical ventilation and hypocarbia in infants with periventricular leukomalacia (PVL). STUDY DESIGN: Matched pair analysis was conducted for 26 infants with PVL and 26 with normal development, who were born between 27 and 32 weeks' gestational age and required mechanical ventilation. The time-averaged carbon dioxide (CO(2)) index, PaCO(2), and pH were calculated every 24 hours for samples obtained from indwelling arterial catheters within the first 72 hours of life. The time-averaged respiratory rate of the ventilator (RR), peak inspiratory pressure (PIP), mean airway pressure (MAP), and ventilator index (VI) were also determined. The time-averaged total respiratory rate (TRR) was determined by observing the movement of the chest wall. The patients' characteristics, antenatal and neonatal variables, and electroencephalographic findings were also compared. RESULTS: The time-averaged CO(2) index was larger, the time-averaged CO(2) lower and the time-averaged pH higher in infants with PVL than in those with normal development on the third day of life. There was no significant difference in the time-averaged RR, PIP, MAP, or VI on any day. TRR was larger in the PVL group than in the control group on each day, but there was no significant difference. No significant difference was observed in the clinical characteristics or neonatal variables. Electroencephalographic abnormalities within 48 hours of life were more frequent in infants with PVL than in those with normal development. CONCLUSION: Hypocarbia was associated with PVL because the time-averaged CO(2) index was larger and the time-averaged PaCO(2) lower in infants with PVL than in those with normal development. However, the ventilator settings were similar among the infants with and without PVL.

Localized amyloidosis and extramedullary plasmacytoma involving the larynx of a child.

Extramedullary plasmacytoma of the larynx and localized laryngeal amyloidosis are 2 uncommon disease entities that are exceedingly rare in children. We report a case of a 12-year-old girl presenting with progressive hoarseness who was subsequently found to have extramedullary plasmacytoma coexisting with localized amyloidosis involving the larynx. Results from the immunohistochemical and molecular studies showed that the tumor cells of the plasmacytoma were monoclonal (kappa-restricted), strongly supporting their neoplastic nature. The biochemical nature of the amyloid deposits was also shown to be of kappa immunoglobulin light chain, suggesting the pathogenetic relationship between the plasmacytoma and amyloid deposition in the larynx of this patient. There was no other evidence of malignancy or amyloidosis elsewhere. On a follow-up period of 4 years, this patient was well and asymptomatic. We believe that this represents the first case in the literature showing the coexistence of extramedullary plasmacytoma and localized amyloidosis of the larynx in children. This case also supports the concept that localized laryngeal amyloidosis may be a manifestation of low-grade B-cell neoplasms.

Upper bound of the expected training error of neural network regression for a Gaussian noise sequence.

In neural network regression problems, often referred to as additive noise models, NIC (Network Information Criterion) has been proposed as a general model selection criterion to determine the optimal network size with high generalization performance. Although NIC has been derived using asymptotic expansion, it has been pointed out that this technique cannot be applied under the assumption that a target function is in a family of assumed networks and the family is not minimal for representing the target true function, i.e. the overrealizable case, in which NIC reduces to the well-known AIC (Akaike Information Criterion) and others depending on a loss function. Because NIC is the unbiased estimator of generalization error based on training error, it is required to derive the expectations of errors for neural networks for such cases. This paper gives upper bounds of the expectations of training errors with respect to the distribution of training data, which we call the expected training error, for some types of networks under the squared error loss. In the overrealizable case, because the errors are determined by fitting properties of networks to noise components, including in data, the target set of data is taken to be a Gaussian noise sequence. For radial basis function networks and 3-layered neural networks with bell shaped activation function in the hidden layer, the expected training error is bounded above by sigma2* - 2nsigma2*logT/T, where sigma2* is the variance of noise, n is the number of basis functions or the number of hidden units and T is the number of data. Furthermore, for 3-layered neural networks with sigmoidal activation function in the hidden layer, we obtained the upper bound of sigma2* - O(log T/T) when n > 2. If the number of data is large enough, these bounds of the expected training error are smaller than sigma2* - N(n)sigma2*/T as evaluated in NIC, where N(n) is the number of all network parameters.

Predictive value of acetylcholine stimulation testing for oligohidrosis caused by zonisamide.

We studied 16 patients for whom zonisamide was newly prescribed. Acetylcholine stimulation testing was performed about 1 month after zonisamide was initiated. Oligohidrosis occurred in none of the four with a normal response and in four of the 12 with a decreased response. Acetylcholine stimulation testing predicted oligohidrosis with a sensitivity of 1 and a false-positive rate of 0.67. The acetylcholine stimulation test was sensitive in detecting oligohidrosis caused by zonisamide, although the false-positive rate was high.

ADAMTS-1 cleaves a cartilage proteoglycan, aggrecan.

A disintegrin-like and metalloproteinase with thrombospondin type I motifs-1 (ADAMTS-1) is an extracellular matrix-anchored metalloproteinase. In this study we have demonstrated that ADAMTS-1 is able to cleave a major cartilage proteoglycan, aggrecan. N-terminal sequencing analysis of the cleavage product revealed that ADAMTS-1 cleaves the Glu(1871)-Leu(1872) bond within the chondroitin sulfate attachment domain of aggrecan. In addition, deletional analysis demonstrated that the C-terminal spacer region of ADAMTS-1 is necessary to degrade aggrecan. These results suggest that ADAMTS-1 may be involved in the turnover of aggrecan in vivo.

[Effectiveness of domiciliary noninvasive positive pressure ventilation in improving blood gas levels and the performance of daily activities. NIPPV Study Group].

Noninvasive positive pressure ventilation (NIPPV) is widely used in the domiciliary treatment of chronic ventilatory failure. We conducted a multicenter, prospective study of the effects of NIPPV on blood gas levels, subjective symptoms, and the performance of daily activities. Fifty-one hospitalized patients with chronic ventilatory failure were enrolled in the study. Using NIPPV, 44 patients were able to live at home for more than 1 month, and 43 for more than 3 months. PaO2 and PaCO2 were 69.1 +/- 13.1 Torr (n = 25) and 70.8 +/- 11.0 Torr (n = 27) before NIPPV and 77.9 +/- 12.5 Torr (n = 26) and 61.0 +/- 11.2 Torr (n = 27) after 1 month of domiciliary treatment, respectively. Blood gas values were significantly improved after NIPPV. Patients experienced alleviation of all subjective symptoms. Dyspnea when wearing clothes, walking on flat levels, or climbing stairs also subsided, and was significantly reduced during daily activities other than eating among those patients who needed any help in performing their activities prior to the initiation of NIPPV. We concluded that NIPPV is an effective and convenient means of domiciliary ventilation that can help patients achieve greater independence in daily life. NIPPV can be expected to play a central role in home respiratory care for patients with hypercapnic respiratory failure.

Early recognition of benign partial epilepsy in infancy.

PURPOSE: The aim of this study is to determine how precisely we can recognize the outcome in infants with epilepsy beginning in the first year of life. METHODS: We performed a prospective 5-year follow-up study on 63 patients who developed epilepsy in the first year of life. We first judged that patients met the criteria of "possible benign partial epilepsy in infancy (BPEI)" on enrollment in this study. At 2 years of age, we reevaluated the seizure and developmental outcome in the patients who were diagnosed as having "possible BPEI." We finally judged that patients met the criteria of "definite BPEI" at age 5 years. "Possible BPEI" was defined as epilepsy meeting all the following conditions: (a) complex partial seizures and/or secondarily generalized seizures; (b) normal psychomotor development and neurologic findings before onset; (c) normal interictal electroencephalograms; (d) normal cranial computed tomography (CT) and magnetic resonance imaging (MRI) findings; and (e) no seizures during the first 4 weeks of life. "Definite BPEI" was defined as epilepsy meeting all the following criteria in addition to those of "possible BPEI": (a) normal psychomotor development beyond age 5 years, and (b) no seizures beyond age 2 years. RESULTS: Thirty-two of the 63 patients met the inclusion criteria completely and were included in the "possible BPEI" group. Twenty-five of the 32 patients completed the 5-year follow-up. At age 2 years, four patients were excluded from the "possible BPEI" group because of seizure recurrence and/or delayed development. By age 5 years, one had a recurrence of seizures, and another exhibited mildly delayed psychomotor development. We finally diagnosed 19 patients as having "definite BPEI." "Definite BPEI" accounted for 76% of the patients diagnosed as having "possible BPEI" at the first presentation and 90% of those who met the conditions on reevaluation at age 2 years. CONCLUSIONS: Recognition of BPEI is possible, to some extent, at the first presentation, and reevaluation at age 2 years is useful for a more precise diagnosis.

Bilateral basal ganglia-thalamic lesions subsequent to prolonged fetal bradycardia.

We report two infants with bilateral basal ganglia-thalamic lesions subsequent to prolonged fetal bradycardia. Cardiotocogram revealed severe bradycardia lasting for more than 20 min in both. They demonstrated a significant encephalopathy, abnormal muscle tones and signs of brainstem injury. Clinical or electrical seizures were not observed in either of them. CT during early neonatal period demonstrated decreased tissue attenuation in basal ganglia and thalami in the absence of extensive cortical changes. Both of them developed severe mental retardation and quadriplegia. MRI in late infancy demonstrated abnormal high intensity areas in bilateral basal ganglia, thalami and around central sulci on T2-weighted image. Close correlation between prolonged fetal bradycardia and basal ganglia-thalamic lesion was suggested.

ADAMTS-1: a metalloproteinase-disintegrin essential for normal growth, fertility, and organ morphology and function.

A disintegrin and metalloproteinase (ADAM) represents a protein family possessing both metalloproteinase and disintegrin domains. ADAMTS-1, an ADAM family member cloned from cachexigenic colon adenocarcinoma, is unusual in that it contains thrombospondin type I motifs and anchors to the extracellular matrix. To elucidate the biological role of ADAMTS-1, we developed ADAMTS-1-null mice by gene targeting. Targeted disruption of the mouse ADAMTS-1 gene resulted in growth retardation with adipose tissue malformation. Impaired female fertilization accompanied by histological changes in the uterus and ovaries also resulted. Furthermore, ADAMTS-1(-/-) mice demonstrated enlarged renal calices with fibrotic changes from the ureteropelvic junction through the ureter, and abnormal adrenal medullary architecture without capillary formation. ADAMTS-1 thus appears necessary for normal growth, fertility, and organ morphology and function. Moreover, the resemblance of the renal phenotype to human ureteropelvic junction obstruction may provide a clue to the pathogenesis of this common congenital disease.

Epilepsy in patients with spastic cerebral palsy: correlation with MRI findings at 5 years of age.

The aim of this study was to determine the relationship between epilepsy and the magnetic resonance imaging (MRI) findings in patients with spastic cerebral palsy at five years of age. We studied 14 patients with congenital anomaly and 116 with perinatal injury. The patients with perinatal injury were subdivided into two groups; those with preterm type injury alone (group P), and those with term type injury with or without preterm type injury (group T). Epilepsy was found in 37 of the 130 patients. The initial type of seizures was partial in 12 patients. infantile spasms in 20 and generalized in five. Kaplan-Meier analysis demonstrated that patients with congenital anomaly had a higher incidence and an earlier onset of epilepsy than those with perinatal injury. Of the patients with perinatal injury, group T patients showed a higher incidence and a later onset of epilepsy than group P patients.

Determination of timing of brain injury in preterm infants with periventricular leukomalacia with serial neonatal electroencephalography.

OBJECTIVE: The aim of this study was to determine the timing of brain injury in infants with periventricular leukomalacia (PVL) with serial electroencephalography (EEG) recordings during the neonatal period. PATIENTS AND METHODS: We evaluated 172 preterm infants having a gestational age <33 weeks and weighing <2000 g. Initial EEG was recorded within 72 hours of life and then recorded once every 1 to 4 weeks. Serial cranial ultrasonography was performed and cystic PVL was diagnosed when multiple cystic formations of >3 mm in diameter were observed. RESULTS: Of the 172 infants studied, 26 were diagnosed as having cystic PVL by ultrasonography. EEG abnormalities were observed in 25 of 26 infants with PVL, although EEG abnormalities were seen in 20 of 146 infants without PVL. The initial EEG recordings were normal in 7 infants, but EEG abnormalities were observed later in 6 of these infants. In these 6 infants, the timing of injury was presumed to be postpartum. Only acute stage abnormalities were observed on initial EEG recording in 14 infants, and the timing of injury was presumed to be just before or around birth. Chronic stage abnormalities were recognized already on initial EEG recordings in the other 5 infants, and the timing of injury was presumed to be some time before birth. CONCLUSIONS: Our study indicates that it may be possible to determine the timing of injury in infants with PVL by serial EEG recordings.