Intrathoracic retroesophageal goiter causing tracheal stenosis

A 65-year-old woman presented with stridor revealed a mass on a chest X-ray on physical examination. A huge goiter arising in the left lobe of the thyroid had extended retroesophageally and across the midline to the right side of the posterior mediastinum far caudally down to the level of the carina. The trachea was remarkably compressed. Surgery was performed via a combined thoracic and cervical approach, and the tumor was completely removed with resultant relief from stridor. The patient is presently doing well at 1 year after the operation.

Phosphatoquinones A and B, novel tyrosine phosphatase inhibitors produced by Streptomyces sp

Phosphatoquinones A and B were isolated from the cultured broth of Streptomyces sp. TA-0363 and their structures were elucidated by spectroscopic analyses. Phosphatoquinones A and B inhibited the protein tyrosine phosphatase activity prepared from human Ball-1 cells with IC50 of 28 microM and 2.9 microM, respectively.

Reduction of hamster egg abnormalities in repeatedly induced ovulation by using the minimum effective dose of human chorionic gonadotrophin

The minimum dose of human chorionic gonadotrophin needed to induce ovulation was determined in hamsters, in which the luteinizing hormone surge was blocked by administration of phenobarbitone. Doses of 1.0, 2.5, 5.0 and 10.0 IU human chorionic gonadotrophin were injected subcutaneously, and 5.0 IU was found to be the minimum dose needed to induce ovulation in all of a group of seven hamsters. When this minimum dose was used to induce ovulation repeatedly, one, two or three times, in groups of seven hamsters the percentages of abnormal eggs seen were 5.3%, 5.6% and 6.4%, respectively. These results indicate that the marked increases in the proportions of abnormal eggs produced when ovulation is repeatedly induced, which have been observed in previous studies, can be prevented by using the minimum effective dose of human chorionic gonadotrophin.

Comparison of urinary 6beta-hydroxycortisol/cortisol ratio between neonates and their mothers

AIMS

To assess CYP3A enzyme activity in human neonates by measuring the urinary 6beta-hydroxycortisol/cortisol (6beta-OHF/C) ratio.

METHODS

Fifty-six mature male neonates with normal delivery, seventeen of their mothers and twenty-four healthy non-pregnant young women participated in this study. Urinary 6beta-OHF/C ratio was determined on the day of birth in neonates and their mothers. In addition, changes in the ratio after birth were determined in neonates.

RESULTS

On the day of birth, the urinary 6beta-OHF/C ratio of neonates was significantly higher than that of their mothers (20.5 vs 6.9). In contrast, no significant difference was observed in the mean ratio of urinary 6beta-OHF/C between women with and without pregnancy (6.9 vs 9.0). The urinary 6beta-OHF/C ratio after birth was decreased day by day in neonates.

CONCLUSION

These results indicate that the high urinary 6beta-OHF/C ratio in mature neonates on the day of birth is independent of the activity of CYP3A enzyme in their mothers.

Effects of microgravity on c-fos gene expression in osteoblast-like MC3T3-E1 cells

The paper summarizes the data on proliferation and gravity-related gene expression of osteoblasts that were obtained from an experiment conducted under simulated and real microgravity conditions. Simulated microgravity conditions obtained in a clinostat depress proliferation of both osteoblast-like MC3T3-E1 and HeLa carcinoma cells. This depression of proliferation occurs in a collagen gel culture in which the flow of culture medium by rotation may be reduced. Interestingly, MC3T3-E1 cells which are probably one of target cells to microgravity are more sensitive than the HeLa cells. Simulated microgravity inhibited the epidermal growth factor (EGF)-induced c-fos gene expression in the MC3T3-El cells. To examine in detail the effect of real microgravity on the EGF signal transduction cascade in osteoblasts, MC3T3-E1 cells were cultured in the Cell Culture Experiment Module of the sounding rocket TR-1A6. The EGF-induced c-fos expression in cells was depressed under short-term microgravity conditions in the sounding rocket, while the phosphorylation of mitogen-activated protein kinase (MAPK) was not affected compared with the controls grown on the ground. These results suggest that an action site of microgravity in the signal transduction pathway may be downstream of MAPK.

Pure yolk sac tumor of the ovary with mosaic 45X/46X + mar Turner's syndrome with a Y-chromosomal fragment

A pure yolk sac tumor (endodermal sinus tumor) of the dysgenetic gonad developed in a 23-year-old woman whose karyotype was mosaic 45X/46X + mar Turner's syndrome is reported. Molecular biological studies showed that the patient's DNA contained a fragment of Y chromosome. This case seems to be extremely rare case of developing a pure yolk sac tumor in a patient with mosaic Turner syndrome with a Y-chromosomal fragment.

Selective inhibition of the bacterial peptidoglycan biosynthesis by the new types of liposidomycins

We examined the inhibitory activity against bacterial peptidoglycan biosynthesis, mammalian glycoprotein biosynthesis and growth of BALB/3T3 cells of four different types of liposidomycins which have the structure with or without sulfate and/or 3-methylglutaric acid moieties. Liposidomycins inhibited peptidoglycan biosynthesis about 30 to 500 times more effectively than tunicamycin, whereas liposidomycins inhibited mammalian glycoprotein biosynthesis about 30 to 300 times less effectively than tunicamycin. When the cytotoxic effect of liposidomycins and tunicamycin on the growth of mammalian cells were compared, liposidomycins did not show toxicity against BALB/3T3 cell at 25 microg/ml, though tunicamycin inhibited cell growth by 50% at 0.05 microg/ml. On the basis of these results, it is concluded that liposidomycins are selective antibiotics showing highly specific inhibition toward bacterial peptidoglycan biosynthesis.

[MR cholangiography of congenital biliary malformations in infancy]

We presented MR cholangiography (MRC) of congenital biliary malformations in infancy. MRC was obtained during induced sleeping. In two cases of congenital dilation of bile duct, MRC revealed cystic or spindle dilatation of intra- and extra hepatic bile ducts. In one biliary atresia, MRC revealed the serpentine gall bladder and cystic dilatation of the extrahepatic bile duct without connection to the dilated hilar bile duct. MR cholangiography, which can be obtained noninvasively, is useful for the diagnosis and the preoperative assessment of congenital biliary malformations in infancy.

Caspase-mediated activation of a 36-kDa myelin basic protein kinase during anticancer drug-induced apoptosis

A novel anticancer drug, cytotrienin A, isolated from Streptomyces sp., induces apoptosis (or programmed cell death) in human promyelocytic leukemia HL-60 cells within 4 h. To elucidate the mechanism of this process, we performed an in-gel kinase assay using myelin basic protein (MBP) as a substrate and found the activation of kinase with an apparent molecular mass of 36 kDa (p36 MBP kinase). The dose of cytotrienin A required to activate p36 MBP kinase was consistent with that required to induce apoptotic DNA fragmentation in HL-60 cells. This p36 MBP kinase was activated with kinetics distinct from the activation of JNK (c-Jun N-terminal kinase)/stress-activated protein kinase and p38 MAPK (mitogen-activated protein kinase). Importantly, the p36 MBP kinase was immunologically different from MAPK superfamily molecules such as ERK1, JNK isoforms, and p38 MAPK. In addition, the p36 MBP kinase activation and apoptotic DNA fragmentation were inhibited by antioxidants such as N-acetylcysteine and reduced-form glutathione. The p36 MBP kinase activation was also observed during hydrogen peroxide (H2O2) and okadaic acid-induced apoptosis. Although a specific inhibitor of caspase-3-like proteases (Ac-DEVD-CHO) or a specific inhibitor of caspase-1-like proteases (Ac-YVAD-CHO) did not block the cytotrienin A-, H2O2-, or okadaic acid-induced apoptosis, a broad specificity inhibitor of caspases (Z-Asp-CH2-DCB) strongly inhibited the apoptosis of HL-60 cells. Surprisingly, Z-Asp-CH2-DCB inhibited the activation of p36 MBP kinase induced by cytotrienin A or H2O2, but did not inhibit the activation of JNK/stress-activated protein kinase and p38 MAPK. Taken together, these results indicate that p36 MBP kinase activation is downstream of the activation of Z-Asp-CH2-DCB-sensitive caspases, and reactive oxygen species could be included in the apoptotic events. Moreover, according to the Western blotting using the antibodies against MST1/Krs2 or MST2/Krs1, it is suggested that the p36 MBP kinase is an active proteolytic product of MST1/Krs2 and MST2/Krs1, which are originally cloned by virtue of its homology to the budding yeast Ste20 kinase. Thus, the p36 MBP kinase might be a common component of the diverse signaling pathways leading to apoptosis, and controlling this p36 MBP kinase pathway might be a novel strategy for cancer chemotherapy.

Bioprobes for investigating mammalian cell cycle control

Bioprobes are low molecular weight compounds which are useful for investigating mammalian cell functions. The use of bioprobes has substantially assisted the investigation of complex biochemical processes of the mammalian cell cycle. In this review, cell cycle inhibitors mainly isolated from the microorganism are described and their possibility as an antitumor agents is considered. Most cancer cells have some abnormality in the control mechanism of cell cycle progression. Cyclin-dependent kinases (Cdk), which are activated by the binding with the cyclin and simultaneously by the phosphorylation/dephosphorylation of itself, play important roles as engines in the cell cycle. Tubulins are considered to be one of the most important proteins of the cell division machinery. Therefore, Cdk inhibitors and tubulin binders are possible anticancer drugs. Since the function of proteins controlling the cell cycle is also regulated by phosphorylation and dephosphorylation, inhibitors of protein kinases and phosphatases are considered as possible an antitumor agents. We expect that some bioprobes will be developed for clinical use.

Effect of maternal hydration on oligohydramnios: a comparison of three volume expansion methods

OBJECTIVE

To determine the effect of maternal hydration with intravenous (i.v.) isotonic fluid, i.v. hypotonic fluid, and oral water on amniotic fluid index (AFI) in women with oligohydramnios.

METHODS

Patients with low AFI and gestational age over 35 weeks without maternal complications were randomized into four groups (2 L/2 h i.v. isotonic fluid, 2 L/2 h i.v. hypotonic fluid, 2 L/2 h oral water, control). Maternal plasma osmolality, AFI, hematocrit, and hemoglobin concentration were measured before and after hydration.

RESULTS

Eighty-four patients (n=21/group) completed the study without any maternal adverse effects. The mean increase in AFI after hydration was significantly greater in the i.v. hypotonic and oral water groups (2.8+/-1.9, P < .001; 3.8 +/-1.9, P < .001, respectively), but not in the i.v. isotonic group (0.5+/-1.1), compared with the control group (0.5+/-1.1). Significant decreases in maternal hematocrit and hemoglobin concentration were found only after i.v. isotonic hydration (32.0+/-2.9 to 29.5+/-2.3, P < .001; 11.0+/-1.6 to 10.1+/-1.4, P < .001, respectively). Changes in maternal osmolality correlated with the changes in AFI in both the i.v. hypotonic group (r=.58, P < .001) and oral water group (r =.63, P < .001).

CONCLUSION

Maternal hydration with either i.v. hypotonic fluid or oral water increases AFI in oligohydramnios. Maternal osmotic change rather than maternal volume expansion had a more direct impact on increasing amniotic fluid volume with short-term acute hydration.

Induction of apoptosis by Smad3 and down-regulation of Smad3 expression in response to TGF-beta in human normal lung epithelial cells

Smad family members are essential intracellular signaling components of the transforming growth factor-beta (TGF-beta) superfamily involved in a range of biological activities. Two highly homologous molecules, Smad2 and Smad3, have so far been identified as receptor-activated Smads for TGF-beta signaling and have become the focus of intensive studies. However, no definite differences in regulation or function have been established between these TGF-beta signaling molecules. In the present study, we show that the expression of Smad3, but not its close relative, Smad2, is down-regulated by TGF-beta mediated signals themselves in human lung epithelial cells. This down-regulation of Smad3 by TGF-beta treatment did not appear to result from shortening of the half-life of Smad3 mRNA. Constitutive expression of Smad3 in the presence of TGF-beta induced apoptotic cell death, with an adverse effect on the cell growth of human lung epithelial cells. Apoptotic cell death could also be induced by forced expression of Smad2 in the presence of TGF-beta, but less efficiently than by that of Smad3. These findings clearly define the distinctions between Smad2 and Smad3 for the first time in that a qualitative difference was observed with regard to the regulation of their expression in response to TGF-beta, while Smad2 and Smad3 appeared to have quantitatively different capabilities regarding the induction of apoptotic cell death in human lung epithelial cells.

Tissue factor is associated with the nonbacterial thrombotic endocarditis induced by a hypobaric hypoxic environment in rats

High-altitude hypoxia causes a hypercoagulable state. In our previous study on the blood coagulation system in rats, nonbacterial thrombotic endocarditis (NBTE) developed after 4-12 weeks' exposure to the equivalent of 5500 m in altitude. We hypothesized that TF (tissue factor)-producing cells in the cardiac valves might be induced by the hypobaric hypoxic environment (HHE) and then trigger NBTE. A total of 170 male Wistar rats were housed in a chamber at the equivalent of 5500 m altitude for 1-12 weeks. We measured TF activity in the plasma and studied morphological changes in the mitral valves using immunohistochemical and immunoelectrical methods for TF protein and in situ hybridization for TF mRNA. After 4 weeks or more of exposure to HHE, 28 of the 56 surviving rats had developed NBTE. After 4-8 weeks' exposure to HHE, the plasma TF activity level was significantly higher than in control rats. There was a significant correlation between plasma TF activity and the incidence of NBTE. After 1 weeks' exposure to HHE, immunoreactivity for TF protein was detected in foamy macrophages and stromal cells in the cardiac valves. In rats with NBTE, TF protein was present in foamy macrophages and spindle stromal cells and focally present in the extracellular matrix. TF mRNA was detected in some foamy macrophages within the thrombus, TF protein was localized to the rough endoplasmic reticulum and plasma membrane of many macrophages, some fibroblasts, and a few endocardial cells. TF is associated with the pathogenesis of the NBTE induced by exposure to HHE. The accumulation of TF-producing macrophages during exposure to HHE may be responsible for initiating thrombus formation.

Intraoperative TEE during mitral valve repair: does it predict early and late postoperative mitral valve dysfunction?

BACKGROUND

Intraoperative transesophageal echocardiography (TEE) using color Doppler flow mapping can accurately measure residual mitral regurgitation (MR), but it is unknown to what extent such measurements correlate with those obtained with postoperative transthoracic echocardiography (TTE).

METHODS

We used intraoperative TEE (based on direct planimetry of the maximal regurgitant jet area) to measure residual MR in 42 patients who underwent mitral valve reconstruction for MR and compared these measurements with those obtained with early and late postoperative TTE.

RESULTS

Residual MR as measured by intraoperative TEE correlated significantly with values obtained with both early (r = 0.66; p < 0.0001) and late (r = 0.71; p < 0.0001) postoperative TTE. Forty patients with no or trivial MR (< or =2 cm2) as measured by intraoperative TEE also had no or trivial MR as measured by early (probability of 87.5%) and late (probability of 80.0%) postoperative TEE. Of the 40 patients, 6 had clinically insignificant mild MR (< or =4 cm2) when measured by late postoperative TTE. Two other patients in whom intraoperative TEE showed mild MR developed moderate regurgitation about 3 months later.

CONCLUSIONS

Intraoperative TEE correlates with early and late postoperative TTE in measurement of residual MR, suggesting it can reliably predict early and late postoperative mitral valve dysfunction.

Primary mediastinal seminoma. Efficacy of chemo-radiotherapy alone

A treatment policy must be established for primary mediastinal seminoma. We have treated five patients with this entity during 18 years. All our patients presented with a bulky mass as is usual for this disease. Our first patient was treated surgically and then with radiation, but developed recurrences and died 11 years after the initial diagnosis. Three subsequent patients, one with multiple lymph node metastases, were treated with radiation followed by cisplatin. Our most recent patient received two courses of adriamycin-reinforced PVB, and then radiation for consolidation, followed by another course of chemotherapy. For these five patients, the 5- and 10-year survival rates were both 100%. A review of the literature emphasized the fact that either radiation or surgery has recently been replaced by chemotherapy as the front-line treatment of this rare tumor in light of a better response to the latter form of treatment. We fully agree with this policy. Based on the favorable long-term results of our patients we conclude that chemo-radiotherapy can cure primary mediastinal seminoma, even in its extended form, without surgery. An initial three courses of cisplatin-based chemotherapy like adriamycin-reinforced PVB or BEP should be followed by radiation of up to 4,000 cGy for consolidation. Surgery may play a limited role for tumors that are small at presentation, or for any possible viable residue seen on roentgenograms following chemo-radiotherapy.

Genetic differentiation of complete hydatidiform moles coexisting with normal fetuses by short tandem repeat-derived deoxyribonucleic acid polymorphism analysis

OBJECTIVE

We applied deoxyribonucleic acid polymorphism analysis on the basis of differences in the number of short tandem repeat sequences to genetically differentiate dizygotic twins with complete hydatidiform moles and normal fetuses from partial moles presenting a similar appearance.

STUDY DESIGN

Six pregnant women exhibiting apparent moles and coexisting fetuses were the subjects of this study. Eight polymorphic loci including short tandem repeat sequences were amplified by polymerase chain reaction from deoxyribonucleic acid of peripheral leukocytes of parents, umbilical cord, grossly normal placenta-villi, and molar tissue. The segregation of alleles among samples were determined by comparing band patterns on polyacrylamide gels.

RESULTS

In all 6 cases amplifications of polymorphic loci provided sufficient information to determine the parental origin. At informative loci the alleles of cord and placenta-villi were transmitted from both patients and husbands whereas molar tissue had only paternal alleles. These allele segregations indicated 2 different genetic origins, namely, normal parental for a fetus and androgenetic for molar tissue, and thus the diagnosis of dizygotic twins with a complete hydatidiform mole and a normal fetus was made. Additionally, the molar component was defined as a heterozygous mole in 2 cases.

CONCLUSION

Short tandem repeat-derived deoxyribonucleic acid polymorphism analysis was demonstrated to be a useful and precise procedure for the differential diagnosis of a complete hydatidiform coexisting with a normal fetus and the determination of its zygosity as well.

Tryprostatin A, a specific and novel inhibitor of microtubule assembly

We have investigated the cell cycle inhibition mechanism and primary target of tryprostatin A (TPS-A) purified from Aspergillus fumigatus. TPS-A inhibited cell cycle progression of asynchronously cultured 3Y1 cells in the M phase in a dose- and time-dependent manner. In contrast, TPS-B (the demethoxy analogue of TPS-A) showed cell-cycle non-specific inhibition on cell growth even though it inhibited cell growth at lower concentrations than TPS-A. TPS-A treatment induced the reversible disruption of the cytoplasmic microtubules of 3Y1 cells as observed by indirect immunofluorescence microscopy in the range of concentrations that specifically inhibited M-phase progression. TPS-A inhibited the assembly in vitro of microtubules purified from bovine brains (40% inhibition at 250 microM); however, there was little or no effect on the self-assembly of purified tubulin when polymerization was induced by glutamate even at 250 microM TPS-A. TPS-A did not inhibit assembly promoted by taxol or by digestion of the C-terminal domain of tubulin. However, TPS-A blocked the tubulin assembly induced by inducers interacting with the C-terminal domain, microtubule-associated protein 2 (MAP2), tau and poly-(l-lysine). These results indicate that TPS-A is a novel inhibitor of MAP-dependent microtubule assembly and, through the disruption of the microtubule spindle, specifically inhibits cell cycle progression at the M phase.

Bronchial wall schwannoma removed by sleeve resection of the right stem bronchus without lung resection

A 28-year-old man presented with a bronchial wall schwannoma occurring in the right main to the intermediate bronchus. The tumor was resected en-bloc with the stem bronchi without pulmonary resection. Airway reconstruction consisted of an end-to-end anastomosis of the intermedius bronchus to the right main bronchus, and an end-to-side anastomosis of the right upper lobe bronchus to the lateral wall of the trachea. Postoperative course was uneventful. Bronchoplastic procedure with preservation of the lung parenchyma seems to be the technique of choice for benign tumors occurring intramurally in the stem bronchus.

New types of liposidomycins that inhibit bacterial peptidoglycan synthesis and are produced by Streptomyces. I. Producing organism and medium components

Liposidomycins are atypical lipid-bearing nucleoside antibiotics that inhibit bacterial peptidoglycan synthesis. A producing strain was identified as a Streptomyces sp. from its cultural characteristics and physiological properties. It produced new types of liposidomycins that lacked sulfate and/or 3-methylglutaric acid moieties present in known liposidomycins by changing medium components. Sucrose and malt extract were particularly suitable sources for specific production of the new types of liposidomycins.

New types of liposidomycins that inhibit bacterial peptidoglycan synthesis and are produced by Streptomyces. II. Isolation and structure elucidation

Various new liposidomycins were isolated from a culture of the strain Streptomyces sp. SN-1061M by changing medium components and they were classified into four types (I-IV) based on their structures. They were purified by butanol extraction, silica gel and LH-20 column chromatographies, and high performance liquid chromatography on ODS columns. Type (I) has the original structure which has sulfate and 3-methylglutaric acid moieties. Type (II) has no 3-methylglutaric acid moiety and type (III) has no sulfate moiety. Type (IV) has neither moiety. Type (III) and (IV) compounds, which have no sulfate moiety, exhibited more potent antimicrobial activity.