Biomedical subjects

H Sakamoto

Publications and source records attributed to H Sakamoto.

At least 325 records · Page 18Linked to original sources

PubMed1997

Mucin antigen expression in gastric carcinomas of young and old adults.

The striking differences in the histological features of gastric cancers in young and old adults have been thought to be related to differences in the biological behavior of these cancers. Recently, a new grading system (Goseki's classification) showed that the prognosis of the patient is particularly related to the mucin content of the carcinoma. In this study, we examined differences in mucin antigen expression in cancers from young and old adults and whether antigen expression is related to the clinical outcome. The expression of two mucin core proteins (DF3 antigen [MUC1 gene product] and MRP antigen [MUC2 gene product] and a mucin-type carbohydrate antigen [sialosyl-Tn; STn]) was examined immunohistochemically in gastric cancers from 69 young adults (30 to 39 years of age) and 110 old adults (80 to 89 years of age). The incidence rates of the three histological types (tubular adenocarcinoma, poorly differentiated adenocarcinoma, and signet-ring cell carcinoma) were different in the young and old adults. However, among the mucin antigens examined, only DF3 showed significantly higher frequency of expression in the old adults, and the difference was seen only in tubular adenocarcinomas (young, 43%; old, 68%) and poorly differentiated adenocarcinomas (young, 19%; old, 49%). In these two histological types, there was no difference in the frequency of MRP or STn expression between the young and old adults, although the old adults showed a high incidence of intestinal metaplasia that was positive for both antigens. Signet-ring cell carcinomas showed no significant difference in expression rates of the three antigens in young and old adults, but there were significantly higher expression rates in young patients for both MRP (young, 67%; old, 65%) and STn (young, 71%; old, 57%) and a lower rate of DF3 expression (young, 0%; old, 14%). In both young and old adults, the patients with DF3-positive carcinomas showed significantly poorer survival than those without DF3 expression, whereas there was not significant difference in the survival of the patient groups with positive and negative MRP or STn reactivity. In conclusion, the expression of DF3 was influenced by the age of patients and was related to the outcome. In contrast, MRP and STn expression was related more to the histological pattern of the tumor than to the age of the patient and did not correlate with the outcome.

Adenocarcinoma↗

PubMed1997

Vertebral artery occlusion after subarachnoid hemorrhage from a dissecting aneurysm of the vertebral artery: case report.

BACKGROUND: Generally speaking, occlusion of the vertebral artery is a finding of a dissecting aneurysm associated with completed stroke. We present a case of a vertebral dissecting aneurysm that produced subarachnoid hemorrhage (SAH). Angiography on the day of hemorrhage, however, demonstrated complete occlusion of the vertebral artery. CASE PRESENTATION: A 44-year-old hypertensive woman suffered a sudden onset of headache and vomiting followed by loss of consciousness due to SAH. Angiography on the day of hemorrhage revealed a complete occlusion of the right vertebral artery just distal to the dissecting aneurysm. This is the first report of such a case. The patient was still considered to be at significant risk of rerupture. Craniotomy and clip occlusion of the right vertebral artery and the origin of the right posterior inferior cerebellar artery were carried out to trap the thin-walled sac. At discharge, the patient had recovered completely except for some left limb ataxia, which subsequently disappeared. CONCLUSIONS: Two options are available for the treatment of such a case: surgical or medical treatment. We employed surgery. Which is the preferred approach, however, is a difficult judgment to make at this juncture.

Adult↗

PubMed1997

p53 and HER-2 alterations in renal cell carcinoma.

OBJECTIVES: To investigate protein expression and genetic aberrations of p53 and HER-2 in renal cell carcinoma (RCC) as well as possible association of p53 and HER-2 abnormalities with the tumor behavior of RCC. METHODS: Formalin-fixed and paraffin-embedded tissue blocks from 70 patients with RCC were studied. Protein expression of p53 and HER-2 was assessed immunohistochemically. Following deoxyribonucleic acid extraction from the paraffin sections using a microdissection technique, p53 gene mutations within exons 5 to 8 were examined by polymerase chain reaction (PCR) single-strand conformation polymorphism and HER-2 gene amplification by a differential PCR. RESULTS: Of the 70 RCCs, 16 (22.9%) showed protein expression of p53, with 7 (10%) demonstrating mutations within exons 5 to 7. Additionally, 28 RCCs (40%) displayed protein expression of HER-2, with 12 (17.1%) demonstrating gene amplification. All cases showing p53 mutations or HER-2 amplification represented protein expression of p53 or HER-2, respectively. No cases with negative immunostaining for p53 or HER-2 protein displayed positive results at gene level. Statistical analysis revealed a close relationship between p53 protein expression and the tumor grade, as well as a significant association of HER-2 protein expression and gene amplification with the tumor stage of RCC. CONCLUSIONS: Our observations suggest that the abnormalities of p53 and HER-2 may be involved in the pathogenesis of RCC and that other mechanisms leading to protein expression of p53 and HER-2 may coexist within a single tumor in addition to the genetic aberrations.

Adult↗

PubMed1997

Selective depression of the spinal polysynaptic reflex by the NMDA receptor antagonists in an isolated spinal cord in vitro.

1. The effects of N-methyl-D-aspartate (NMDA) receptor glycine-binding site antagonists 7-chlorokynurenate (7-Clkyn) and (+/-)-3-amino-1-hydroxy-2-pyrrolidone (HA-966) on spinal reflexes in an isolated spinal cord that was maintained in Mg(2+)-free medium in vitro were examined. The actions of 7-Clkyn and HA-966 were compared with those of the channel-site antagonist (i.e., dizocilpine) and NMDA-binding site antagonists--that is, 3-[(+/-)-2-carboxypiperazin-4-yl]-propyl-1-phosphonate (CPP) and DL-2-amino-5-phosphonovalerate (APV). 2. 7-Clkyn and HA-966 produced a selective depression of the polysynaptic reflex (PSR) while negligibly affecting the activity of the monosynaptic reflex (MSR). The PSR was also differentially suppressed by dizocilpine, CPP and APV. The PSR inhibitory activity of the NMDA antagonists was in the following order: dizocilpine > CPP > APV = 7-Clkyn > HA-966. 3. The inhibitory effects of 7-Clkyn on PSR were markedly antagonized by the simultaneous application of D-serine, an agonist for the NMDA receptor glycine-binding sites. However, PSR inhibition by dizocilpine and CPP was unaffected. 4. Inhibition of the PSR by 7-Clkyn persisted in the presence of strychnine, which markedly increased the PSR activity by itself. 5. These findings suggest that the NMDA receptor glycine-binding sites play a role in generating the NMDA receptor-mediated PSR in the spinal cord in vitro.

Animals↗

PubMed1997

Serum levels of specific IgE, soluble interleukin-2 receptor, and soluble intercellular adhesion molecule-1 in seasonal allergic rhinitis.

BACKGROUND: There is increasing evidence that soluble interleukin-2 receptor (sIL-2R) might reflect T cell activation in vivo and soluble intercellular adhesion molecule-1 (sICAM-1) might reflect the ongoing inflammatory response in the inflamed site. OBJECTIVE: The aim of this study was to determine the effect of antihistamine tablets and allergen-specific immunotherapy on the seasonal changes in specific IgE, sIL-2R, and sICAM-1 in the serum of patients with seasonal allergic rhinitis. METHODS: This prospective study included 99 patients with seasonal allergic rhinitis due to Japanese cedar pollens and 27 nonatopic healthy volunteers. The patients were divided into an antihistamine-treated group and an immunotherapy group. Serum samples were collected before and during the pollen season from each patient to determine specific IgE, sIL-2R, and sICAM-1. RESULTS: Levels of sIL-2R before the pollen season did not differ significantly among the nonatopic group, the antihistamine-treated group, and the immunotherapy group. The levels of sICAM-1 before the pollen season were significantly higher in the antihistamine-treated group and in the immunotherapy group than in the nonatopic group. Seasonal increase in specific IgE was significant in the antihistamine-treated group regardless of their clinical outcomes. In contrast, significant increase in specific IgE was observed during the pollen season in poor responders but not in good responders to immunotherapy. Serum levels of sIL-2R and sICAM-1 were significantly increased during the pollen season in poor responders of the antihistamine-treated group and the immunotherapy group. On the other hand, neither seasonal increase in sIL-2R nor sICAM-1 was significant in good responders of the antihistamine-treated group and the immunotherapy group. CONCLUSIONS: Serum levels of sICAM-1 are higher in patients with seasonal allergic rhinitis, even outside of the pollen season when the allergen does not naturally exist. Seasonal changes in serum sICAM-1 as well as sIL-2R and specific IgE are probably objective markers to indicate the clinical efficacy of antihistamines and immunotherapy on seasonal allergic rhinitis.

Adult↗

PubMed1997

Effect of phosphorylation on tetramerization of the tumor suppressor protein p53.

Human tumor suppressor protein p53 is a 393-amino acid phosphoprotein that enhances transcription in response to DNA damage from several genes that regulate cell cycle progression. The tetrameric state of p53 is critical to wild-type function; the p53 tetramerization element is located in the C-terminal region of the protein. This region is phosphorylated at several evolutionarily conserved serines, suggesting that phosphorylation may be an important regulator of p53 function. In order to determine the effect of phosphorylation on tetramer formation, we synthesized phosphopeptides corresponding to p53(Ser303-Asp393) with phosphate incorporated at Ser315, Ser378, or Ser392, and at both Ser315 and Ser392. Equilibrium ultracentrifugation analysis showed that phosphorylation at Ser392 increased the association constant for tetramer formation nearly ten-fold. By itself, phosphorylation at Ser315 or Ser378 had little effect on tetramer formation, but Ser315 largely reversed the effect of phosphorylation at Ser392. Analysis by calorimetry suggests that phosphorylation may influence subunit affinity by an enthalpy driven process.

Amino Acid Sequence↗

PubMed1997

The effect of immunotherapy on the serum levels of eosinophil cationic protein in seasonal allergic rhinitis.

The role of serum eosinophil cationic protein levels in allergic rhinitis is controversial. It is also unclear whether with immunotherapy it is possible to reduce these serum levels in allergic diseases. We studied serum eosinophil cationic protein levels in patients with cedar-induced allergic rhinitis and compared them with non-atopic controls. The second aim of this study was to elucidate whether immunotherapy is capable of decreasing the seasonal elevation in serum eosinophil cationic protein levels in seasonal allergic rhinitis. The serum eosinophil cationic protein levels of the untreated patient group were significantly higher than those of the non-atopic controls. The levels in patients who received immunotherapy for 2 yr were also significantly higher than those of the non-atopic controls. However, the levels were not different between the patients undergoing immunotherapy for over 3 yr and the non-atopic controls. The serum levels of the 31 patients treated with immunotherapy correlated with the duration of immunotherapy. In conclusion, the serum eosinophil cationic protein levels are higher in untreated patients with seasonal allergic rhinitis and this seasonal activation in circulating eosiohophils decreases gradually during immunotherapy, but this inhibitory effect becomes apparent only after a number of years of immunotherapy. This prevention of seasonal eosinophil activation is one of the mechanisms responsible for the clinical effect of immunotherapy.

Adolescent↗

PubMed1997

Serum level of soluble interleukin-2 receptor in patients with seasonal allergic rhinitis.

The rate of release of the soluble form of interleukin-2 receptor (soluble IL-2R) reflects T cell activation in vivo. Since T lymphocytes play a central role in respiratory allergic disorders, the measurement of serum levels of soluble IL-2R may be useful in analysing the disease state of allergic disorders. The study has aimed at investigating the seasonal changes in serum soluble IL-2R in 81 patients with seasonal allergic rhinitis due to Japanese cedar pollens, with special reference to the effect of anti-allergic pharmacotherapy and immunotherapy. Serum samples were obtained twice from each patient, before and during the pollen season, and all the serum samples were simultaneously used for determination of soluble IL-2R and cedar pollen-specific immunoglobin E (IgE). Seasonal elevation in soluble IL-2R was not associated with the good clinical outcome but was associated with the poor clinical outcome, irrespective of pharmacotherapy or immunotherapy. Additionally, successful immunotherapy suppressed seasonal elevation of serum soluble IL-2R more strongly than successful pharmacotherapy, and seasonal increase rates in soluble IL-2R were inversely correlated with the duration of immunotherapy. Seasonal increase rates in soluble IL-2R were significantly correlated with seasonal increase rates in specific IgE in both the medication group and the immunotherapy patients. These results may suggest that seasonal changes in serum soluble IL-2R may serve as an indicator for clinical outcome of seasonal allergic rhinitis, that the magnitude of T cell activation could affect specific IgE production, and that T cell activation could be gradually modulated as immunotherapy proceeds. In conclusion, seasonal changes in serum soluble IL-2R may serve as an objective indicator for clinical outcome of seasonal allergic rhinitis.

Adolescent↗

PubMed1997

Immunotherapy affects the seasonal increase in specific IgE and interleukin-4 in serum of patients with seasonal allergic rhinitis.

This study was designed to determine seasonal changes in cytokines, soluble CD23 and specific IgE in the serum of patients with seasonal allergic rhinitis, and the effect of immunotherapy on these seasonal changes. Fifty-four patients with seasonal allergic rhinitis caused by Japanese ceder pollens were divided into a medication group and an immunotherapy group. The patients of the medication group were treated with non-sedating antihistamines alone during the pollen season. The patients of the immunotherapy group had been treated for variable periods (mean, 5.0 +/- 3.2 years) with immunotherapy using japanese cedar pollen antigens. Serum samples were collected before and during the pollen season from each patient, to determine specific IgE, interleukin-4 (IL-4), interferon-gamma (IFN-gamma) and soluble CD23 levels in serum. A significant increase in specific IgE and IL-4 and a significant decrease in IFN-gamma were observed during the pollen season in the medication group. In contrast, in the immunotherapy group, none of specific IgE, IL-4 and IFN-gamma was significantly changed following natural exposure to pollens. However, these effects were not significant in patients undergoing immunotherapy for 3 or fewer years. Seasonal rates of increase in specific IgE and IL-4 differed significantly between good responders and poor responders to immunotherapy, but seasonal rates of decrease in IFN-gamma did not. A seasonal rate of increase in soluble CD23 was significantly correlated with a seasonal rate of increase in specific IgE, in both the medication and the immunotherapy groups. The seasonal rate of increase in soluble CD23 was significantly smaller in the good responders than in the poor responders to immunotherapy. In conclusion, pollen immunotherapy reduces the seasonal increase in specific IgE, IL-4 and soluble CD23 in serum, and in addition switches the seasonal preferential activation of Th-2 cells to reciprocal activation of Th-1 cells with treatment over several years. It is likely that the mechanisms responsible for the clinically beneficial effects of immunotherapy principally involve the modulation of Th-2 rather than Th-1 cytokines.

Adult↗

PubMed1997

Increased sensitivity of scid heterozygous mice to ionizing radiation.

In the present study, acute effects of ionizing radiation on animal survival, bone marrow cells and fibroblast cell lines of scid homozygous, scid heterozygous and wild-type mice with the same C.B-17 genetic background were examined. The sensitivities to ultraviolet light (UV) and various chemicals, bleomycin, mitomycin C, N-methyl-N'-nitro-N-nitrosoguanidine, methyl methanosulphonate, 5-fluorouracil, 6-mercaptopurine, 4-nitroquinoline 1-oxide and potassium bromate) were also investigated. In addition, micronucleus testing of whole-body irradiated mice was performed. Scid heterozygous mice were found to be less sensitive than the homozygotes but more sensitive to ionizing radiation than wild-type mice, not only in vivo but also for bone marrow cells in vitro, suggesting partial dominance under both conditions. In contrast, there were no differences in sensitivity to UV light and various chemicals, as compared with wild-type and scid heterozygous cell lines, either in vitro or in the micronucleus test.

Animals↗

PubMed1997

Dose optimization of proton and heavy ion therapy using generalized sampled pattern matching.

We have proposed a new dose optimization method for proton and heavy ion therapy using generalized sampled pattern matching, where an optimal beam weight distribution for scanning is obtained as a solution. Using water phantom models, one-dimensional lateral and depth dose distributions were separately optimized, each resulting in a uniform dose distribution within a target region and minimum dose fall-off to minimize undesired irradiation onto neighbouring tissues. Subsequently, we have applied the technique to broad beam three-dimensional proton therapy, leading to a homogeneous dose distribution inside a target and minimized distal and lateral dose fall-off for most convex tumour shapes.

Humans↗

PubMed1997

Absence of human papillomavirus-16 and -18 DNA and Epstein-Barr virus DNA in esophageal squamous cell carcinoma.

To elucidate the association of human papillomavirus (HPV) and Epstein-Barr virus (EBV) with carcinogenesis of the esophagus, 41 surgically resected specimens and 12 cell lines of esophageal squamous cell carcinoma were examined for the presence of HPV DNA and EBV DNA by polymerase chain reaction using primers for the E6 regions of HPV-16 and -18 and for the EBNA 1 region of EBV. We designed the reaction condition to amplify HPV and EBV DNA specifically and detected by gel electrophoresis. In ethidium bromide staining, no band was detected either for the HPV E6 region of for the EBV EBNA 1 gene in any of the surgically resected specimens and the cell lines, although the HPV sequence was detectable by Southern blot hybridization, which is a more sensitive detection method than staining; three out of 41 surgically resected specimens were positive for HPV-18 by Southern blot hybridization of polymerase chain reaction products. However, the number of viral genomes has been estimated as lower than 1 x 10(-3) copies per cell based on the intensity of the hybridization signals. Moreover, the DNA samples extracted from the corresponding non-cancerous esophageal mucosa were also positive for HPV-18, and the intensities of the hybridization signals were almost the same as those of the tumors. The results of our study indicate that HPV-16, HPV-18 and EBV are not generally associated with esophageal carcinogenesis.

Carcinoma, Squamous Cell↗

PubMed1997

Accumulation and clearance of capsanthin in blood plasma after the ingestion of paprika juice in men.

The pharmacokinetics of dietary capsanthin was measured in four male volunteers to assess the bioavailability of oxygenated carotenoids (xanthophylls). Capsanthin was used because this carotenoid was not detected in the men's plasma before ingestion of paprika juice. Supplementing capsanthin-rich paprika juice for 1 wk (equivalent to three doses of 5.4 micromol capsanthin/d; 16.2 micromol/d), the level of capsanthin reached a plateau (0.10-0.12 micromol/L) between d 2 and 7 and was not detectable by d 16. Capsanthin was distributed in the plasma lipoproteins (VLDL, 13 +/- 3%; LDL , 44 +/- 3%; HDL, 43 +/- 3%) at the end of the experiment. In a separate experiment involving the single ingestion of paprika juice (equivalent to 34.2 micromol capsanthin) in the same men, the plasma concentration of capsanthin ranged from 0.10 to 0.29 micromol/L at 8 h after ingestion. In contrast, the elevation of the plasma concentration of an acyclic hydrocarbon carotenoid, lycopene, by a single ingestion of tomato soup (equivalent to 186.3 micromol lycopene) in the same subjects was minimal (0.02-0.06 micromol/L). The areas under the curves (AUC) for capsanthin between 0 and 74 h and for lycopene between 0 and 72 h were 4.68 +/- 1.22 and 0.81 +/- 0.17(micromol.h)/L, respectively. The half-lives (t1/2) were calculated to be 20.1 +/- 1.3 and 222 +/- 15 h for capsanthin and lycopene, respectively. We conclude that the clearance of capsanthin is much faster than that of lycopene, although capsanthin is transported into plasma lipoproteins in larger amounts. This polar carotenoid may be metabolized in the human body more rapidly than lycopene. These data justify further research on the physiological functions of capsanthin and other xanthophylls.

Adult↗

PubMed1997

Aneuploidy induction by benzo[a]pyrene and polyploidy induction by 7,12-dimethylbenz[a]anthracene in Chinese hamster cell lines V79-MZ and V79.

We found that different ploidy effects were induced in four Chinese hamster-derived cell lines (V79-MZ, V79, CHL and CHO-K1) treated through two cell cycles with polycyclic aromatic hydrocarbons in the absence of a metabolic activation system. 5-Bromodeoxyuridine was used to investigate cell cycle delay and sister chromatid exchanges (SCE) induced by the chemicals. Benzo[a]pyrene (BP) induced aneuploidy at 2.5-10 micrograms/ml in V79-MZ cells. 7,12-Dimethylbenz[a]anthracene (DMBA) induced polyploidy at 3.125-6.25 and 6.25-1.25 micrograms/ml in V79-MZ and V79 cells respectively. Higher concentrations caused cell cycle delay and, therefore, did not affect ploidy. BP and DMBA did not induce a significant increase in SCE frequency at the above doses. 3-Methylcholanthrene tested up to its solubility limit (10 micrograms/ml) did not induce numerical aberrations in any cell line. The clastogen mitomycin C, tested up to 0.01 microgram/ml, did not produce numerical aberrations but did significantly increase SCE frequency in all cell lines. The spindle poison colchicine, tested up to 0.1 microgram/ml, induced ploidy changes in the four cell lines that showed different sensitivities. Four cell lines showed no arylhydrocarbon hydroxylase activity, and V79-MZ, but not the other cells lines, showed high glutathione S-transferase activity. Aneuploidy induction by BP and polyploidy induction by DMBA in the absence of S9 mix in vitro have not been described before, and the finding might be due to the effect on tubulin. Due to their specificity and high sensitivity, the V79-MZ and V79 cell lines might be good systems for detecting aneuploidogens.

9,10-Dimethyl-1,2-benzanthracene↗

PubMed1997

Polycistronic expression and RNA-binding specificity of the C. elegans homologue of the spliceosome-associated protein SAP49.

Splicing of mRNA precursors (pre-mRNAs) occurs in a multimolecular complex, termed spliceosome, which is comprised of pre-mRNA, small nuclear ribonucleoprotein particles (snRNPs), and other protein factors including spliceosome-associated proteins (SAPs). SAP49 is thought to be a subunit of the essential splicing factor SF3b and is involved in U2 snRNP function in mammalian cells. We have isolated a Caenorhabditis elegans cDNA encoding an RNA-binding protein with two RNA recognition motifs (RRMs) which shows extensive similarity to the human SAP49. The primary transcript for this C. elegans SAP49 homologue (cSAP49) seems to contain at least two additional cistrons and can be processed into three different mature mRNAs by trans-splicing. The cSAP49 mRNA, like other mRNAs in the same polycistronic unit, is expressed in most of the developmental stages, consistent with its putative essential function for mRNA splicing. By means of an in vitro RNA selection system, we demonstrate that cSAP49 possesses specific RNA-binding activity which resides in its second RRM.

Amino Acid Sequence↗

PubMed1997

Soluble intercellular adhesion molecule-1 level in sera is elevated in perennial allergic rhinitis.

Soluble intercellular adhesion molecule-1 (sICAM-1) in sera was measured in some allergic disorders, but serum sICAM-1 levels in perennial allergic rhinitis remain to be determined. Our study was aimed at elucidating whether the serum sICAM-1 levels in patients with perennial allergic rhinitis are different from those in nonatopic healthy volunteers and whether immunotherapy can modulate sICAM-1 levels. Serum sICAM-1 was determined in 20 nonallergic volunteers and 137 patients with perennial allergic rhinitis by a sandwich enzyme-linked immunosorbent assay. Our study demonstrated that the level of sICAM-1 in untreated patients is significantly elevated, as compared with nonatopic subjects. Immunotherapy could decrease sICAM-1 in perennial allergic rhinitis, but this suppressive effect became apparent only after many years of immunotherapy. In patients on immunotherapy, a close correlation was observed between sICAM-1 and nasal symptom scores. To take these lines of evidence together, a decrease in sICAM-1 might be related to the working mechanism of immunotherapy, and serum sICAM-1 could be used to monitor the effect of immunotherapy.

Adult↗

PubMed1997

Effect of immunotherapy on seasonal changes in serum-specific IgE and IgG4 in patients with pollen allergic rhinitis.

Serum specific IgE and IgG4 in 70 patients with seasonal rhinitis caused by Japanese cedar pollens were determined before and during the pollen season. Seasonal increase rate in specific IgE was significantly smaller in the immunotherapy patients than the pharmacotherapy patients, and seasonal increase in specific IgG4 was significant in the immunotherapy patients only. Seasonal increase rate in specific IgE was not significantly different between the patients who responded markedly to short-term immunotherapy and those who did not. On the other hand, seasonal increase rate in specific IgG4 was significantly different between them. In contrast, seasonal increase rate in specific IgE was significantly smaller in the patients who showed marked response to the long-term immunotherapy than those who did not show marked response to the long-term immunotherapy, but seasonal increase rate in specific IgG4 was not significantly different between them. In conclusion, our results suggest that modulation of specific IgG4 response and specific IgE response might be involved in the early and late symptom relief during immunotherapy, respectively. However, further studies might be necessary to definitively establish the clinical roles of specific IgE and specific IgG4 in immunotherapy.

Adolescent↗

PubMed1997

Effect of magnesium sulfate treatment on neonatal bone abnormalities.

OBJECTIVE: It has been reported that neonatal bone abnormalities occur as a result of long-term intravenous magnesium administration (MgSO4) to pregnant women. The purpose of this retrospective study was to evaluate the frequency of such abnormalities and the clinical background of both mothers and neonates. PATIENTS AND METHODS: We reviewed maternal (114 cases) and neonatal (139 cases) charts from all pregnant women who received intravenous MgSO4 administration for preterm labor and preeclampsia between June 1, 1992, and May 31, 1994. All chest X-ray films were obtained within 48 h after birth and reviewed by a doctor who was unaware of the clinical data. Radiolucent transverse metaphyseal bands of the proximal humerus were considered as abnormal. The subjects were divided into affected (group 1 and 1a) and unaffected (group 2 and 2a) groups. Neonates born to pregnant women given no MgSO4 at the same period, were considered as control. RESULTS: The total number of bone abnormalities in the offspring of mothers receiving MgSO4 amounted to 13 (11.4%). Group 1 consisted of 13 cases and group 2 of 101 cases. In the control group bone abnormalities were not observed (p < 0.05). Significant differences were found between groups 1 and 2 in the gestational ages at the start of MgSO4 administration and at delivery, and in the total duration of administration and doses of MgSO4. Also, cases of multiple pregnancy and pregnancy complicated with impaired glucose tolerance were more prevalent in group 1. According to the results obtained from 139 neonates, cases showing low Apgar and high magnesium score and those receiving respiratory support were more noticeable in group 1a (15 cases). CONCLUSIONS: The gestational ages and the total doses of MgSO4 in pregnant women were the main factors related to the onset of neonatal bone abnormalities, but other factors also have a possible bearing on the condition. In addition, the cases with onset of bone abnormality seemed to be associated with symptoms attributable to hypermagnesemia of neonates.

Bone Development↗