Longitudinal doppler sonographic measurements of vascular impedance in the central and peripheral spiral arteries throughout pregnancy

PURPOSE

We assessed vascular impedance in the spiral arteries in the central and peripheral placental bed throughout uncomplicated pregnancies.

METHODS

Transabdominal color Doppler sonography was used to measure the pulsatility index (PI), resistance index (RI), and peak systolic velocity in the central and peripheral spiral arteries in 94 women with uncomplicated singleton pregnancies. Sonographic examinations took place approximately every 5 weeks from 10 to 40 weeks' menstrual age.

RESULTS

PI, RI, and peak systolic velocity were not different in the central versus the peripheral segments of the spiral arteries. The PI and RI values of central spiral arteries after 25 weeks' menstrual age. The PI and RI values of peripheral arteries decreased after 20 weeks' menstrual age.

CONCLUSIONS

Additional subjects are needed to clarify changes in the impedance of central and peripheral spiral arteries over the course of normal and complicated pregnancies.

Carrier analysis and prenatal diagnosis of congenital adrenal hyperplasia caused by 21-hydroxylase deficiency in Chinese

Congenital adrenal hyperplasia (CAH) is a common autosomal recessive disorder mainly caused by defects in the steroid 21-hydroxylase (CYP21) gene. We screened 1,000 healthy people, using a previously developed differential PCR method combined with single-strand conformation polymorphism and amplification-created restriction site methods for the carrier detection of the CYP21 gene deficiency. Our results indicated that the rate of occurrence of the heterozygous CAH carrier was about 12 in 1,000, with a gene frequency of 0.0060 and an incidence frequency of 1 in 28,000 in the Chinese population. In addition, 9 cases of CAH families were performed with prenatal diagnosis. Among them, 3 cases were diagnosed as the severe form, 4 cases carried the heterozygous mutation, and 2 were normal. This is the first report of carrier frequency analysis and prenatal diagnosis of 21-hydroxylase deficiency in Chinese.

Mutation analysis of the putative tumor suppressor gene PTEN/MMAC1 in cervical cancer

OBJECTIVE

PTEN/MMAC1, a candidate tumor suppressor gene located at chromosome 10q23.3, was recently identified and found to be homozygously deleted or mutated in several different types of human tumors. The aim of this study is to determine whether PTEN/MMAC1 is a target for 10q loss of heterozygosity in cervical cancer.

METHOD

We examined 50 primary cervical carcinoma specimens using a PCR-based assay followed by SSCP and direct sequencing. The genomic DNA was also confirmed by Southern blot analysis.

RESULTS

All specimens except one, which has a 7-base deletion, showed a negative result. Among them, 30 randomly selected cases and their paired noncancerous tissue were further screened using nested RT-PCR. Six of 30 cervical cancerous tissues had aberrant transcripts. However, 4 of the matched noncancerous tissues also had aberrant transcripts. Southern blot analysis of the entire genomic DNA did not reveal any evidence of gene alteration.

CONCLUSIONS

Sequence abnormalities in the PTEN/MMAC1 gene were only detected in 1 of 50 cervical cancers analyzed indicating that aberrant PTEN/MMAC1 function is an uncommon event in the development of cervix cancers. However, similar to studies with the TSG101 gene, screening for aberrant transcripts of PTEN/MMAC1 with nested RT-PCR may detect transcripts, which, although they vary from the normal size, may not be related to oncogenesis as they are also frequently found in normal tissues of the same patient.

Molecular analysis of Duffy, Yt and Colton blood groups in Taiwanese, Filipinos and Thais

We used a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method for DNA-based typing of Duffy, Yt and Colton blood groups in Taiwanese, Filipinos and Thais. A total of 200 Taiwanese, 115 Filipinos and 105 Thais were studied. In the Duffy blood group in Taiwanese, 180 cases (90%) were homozygote of Fya, 18 cases (9%) were double heterozygote of Fya and Fyb, and 2 cases (1%) were homozygote of Fyb. In Filipinos, 98 cases (85.2%) were homozygote of Fya, 16 cases (14.0%) were double heterozygote of Fya and Fyb and 1 case (0.8%) was homozygote of Fyb. In Thais, 87 cases (82.9%) were homozygote of Fya, 18 cases (17.1%) were double heterozygote of Fya and Fyb, and no case of Fyb was found. These results correlate well with serological phenotype. For the Yt blood group, only YT1 was found in Taiwanese. Among Filipinos, 114/115 (99.1%) was YT1/1 and 1/115 (0.9%) was YT1/2. In Thais, 103/105 (98.1%) was YT1/1 and 2/105 (1.9%) was YT1/2. For the Colton blood group, the results showed that there was only Coa allele in these three populations. Our results provide the first data of the Yt and Colton blood groups in these three populations.

Cytogenetic study of workers exposed to chromium compounds

The frequency of sister chromatid exchanges (SCEs), high SCE frequency cells (HFCs), and genetic polymorphism of genotypes glutathione S-transferase (GST) M1 and T1 were analyzed in peripheral lymphocytes of 35 workers occupationally exposed to chromium (Cr) and 35 matched control group. Results showed that workers exposed to Cr showed 6.07 SCE/cell, as compared to 4.76 SCE/cell for the control group (p<0.01). Smokers showed a statistically significant higher frequency of SCE than non-smokers in both groups. The work duration of Cr workers was an important factor. Workers exposed for more than 5 years showed a significantly higher level of SCEs (p<0.05). Workers exposed to Cr for 5 or more years had higher HFC rates (51.4%) than those exposed for less than 5 years (22.9%), with an odds ratio of 4.5 times than those exposed for less than 5 years. In HFC analysis, Cr workers who smoked showed a higher level of HFC (60%) than the control group (5.7%) and also had a higher odds ratio (60.4) compared with the control group. Among non-smokers, the odds ratio was 9.0. Another objective of this study is to investigate the relationship between SCE and genetic polymorphisms of GST M1 and T1 in Cr workers. The results showed that the incidence of GSTM1 null genotype was 60% in the control group and 77.1% in Cr workers, and percentages of GSTT1 deletion were 42.9% and 62.9% in control and exposed individuals, respectively. There was a slightly increased frequency of SCE among Cr workers with GSTM1 null genotype as opposed to non-null genotype individuals. A similar result was seen among the control group; however, there were no statistically significant differences. In conclusion, the current study found the positive induction of SCE in workers who smoked or/and were exposed to Cr. However, different GST genotypes did not influence the level of cytogenetic damage between groups. Despite slight variation in numbers, they all appear to be not different.

A mouse model for spinal muscular atrophy

The survival motor neuron gene is present in humans in a telomeric copy, SMN1, and several centromeric copies, SMN2. Homozygous mutation of SMN1 is associated with proximal spinal muscular atrophy (SMA), a severe motor neuron disease characterized by early childhood onset of progressive muscle weakness. To understand the functional role of SMN1 in SMA, we produced mouse lines deficient for mouse Smn and transgenic mouse lines that expressed human SMN2. Smn-/- mice died during the peri-implantation stage. In contrast, transgenic mice harbouring SMN2 in the Smn-/- background showed pathological changes in the spinal cord and skeletal muscles similar to those of SMA patients. The severity of the pathological changes in these mice correlated with the amount of SMN protein that contained the region encoded by exon 7. Our results demonstrate that SMN2 can partially compensate for lack of SMN1. The variable phenotypes of Smn-/-SMN2 mice reflect those seen in SMA patients, providing a mouse model for this disease.

Normal values of inner canthal distance, interpupillary distance and palpebral fissure length in normal Chinese children in Taiwan

Ocular measurements, including inner canthal distance, outer canthal distance, interpupillary distance, and palpebral fissure length are important in the evaluation of congenital deformities and posttraumatic telecanthus. In this research, 4446 normal Chinese children in Taiwan were enrolled in our study. The sample of 284 full term neonates, 2742 infants and children aged from 1 month to 3 years, and 1420 preschool children were measured for inner canthal distance, outer canthal distance, interpupillary distance and palpebral fissure length. We calculated the mean value and standard deviation of the ocular measurements in normal Chinese newborns, infants and preschool children in Taiwan under 5 years. No significant sex differences were observed. Compared with previous studies, inner canthal distance, outer canthal distance and interpupillary distance in Chinese children in Taiwan were wider than those in Caucasian children, but the palpebral fissure length was not significantly different. We also found that inner canthal distance was wider than palpebral fissure length at the same age; therefore it was not correct to diagnose hypertelorism in Chinese children in Taiwan; as if an imaginary third eye could fit between the eyes. Thus, we suggest that measurements should be adjusted with normal standards specific for race. Consideration of the position of eyes is relevant for the diagnosis of a large number of syndromes.

Aberrant transcripts of FHIT, TSG101 and PTEN/MMAC1 genes in normal peripheral mononuclear cells

Aberrant transcripts of FHIT and TSG101 using nested RT-PCR were reported in many human tumours. The role of these aberrant transcripts in tumourigenesis is not clear. We, therefore, analyzed the aberrant transcripts of FHIT, TSG101 and PTEN/MMAC1 in peripheral mononuclear cells of normal individuals using nested RT-PCR to explore the role of these genes in cancer development. The results showed that there are at least five types of aberrant transcripts: type I is the deletion at junction located in-between normal exon and intron; type II has deletion of some bases and subsequent insertion of several bases in the deletion area; type III accommodates splicing donor or acceptor site-like sequence; type IV has homologous sequences near the deleted junction; and type V comprises the homologous sequences at the deletion junction. A normal healthy person can have more than one aberrant transcripts of FHIT, TSG101 and PTEN/MMAC1 genes. The size and the number of the transcripts vary and the diversity is unconstrained. It is not depended on the time, condition of the reaction, or the isolation method. From these results, we suggested that the aberrant transcripts of FHIT, TSG101 and PTEN/MMAC1 genes may be the imperfect products of splicesome which occur one in every thousands, ten thousands or more. As a result, these data implied no direct association between the aberrant transcripts and tumourigenesis.

Clinical analysis of a dysentery outbreak in Taichung

In September 1993, we collected 207 patients due to dysentery, who visited the Department of Pediatrics at China Medical College Hospital. In our report, 67.6% of these patients were amebic dysentery, 19.3% were combined infection with amebic and Shigella sonnei dysentery, and 13.1% were Shigella sonnei dysentery. Therefore, amebic dysentery was the predominant cause during this outbreak. The clinical features of this outbreak were, in descending order, watery stool, fever, abdominal pain, mucinous stool and bloody stool. No concurrent liver abscess was discerned. Because there had not been such a clustering of dysentery in Taichung for so many years, we thought that travel to endemic areas might have been the underlying predisposing cause. Most of the school water supplying system was ground water, which might have been contaminated by a few patients returning from endemic areas. We thought that fecal-oral route by contaminated water might have been the primary transmission route.

Insertion/deletion mutations of type I oculocutaneous albinism in chinese patients from Taiwan

Type I oculocutaneous albinism (OCA1) is an autosomal recessive disorder, which is caused by the reduction or the absence of tyrosinase activity in melanocytes of the skin, hair and eyes. Although tyrosinase mutations of OCA1 have been extensively analyzed in most populations worldwide, there is no systemic study of OCA1 mutation in Chinese patients. By use of single strand conformation polymorphism and direct sequencing, we had detected 21 mutant alleles out of 24 OCA1 chromosomes screened (87.5%). Detected mutant alleles include one splicing site, three insertion/deletion and five missense mutations, of which the splicing site nucleotide alteration (IVS 1-3C>G) and two each of the insertion/deletion (232-233 ins GGG and 861-862 del TT) and missense mutations (Cys 289 Gly and Trp 400 Leu) are novel. The ins/del mutations accounts for about 37.5% in Chinese OCA1 alleles. The 232-233 ins GGG, one of the novel mutations, was found to be most frequent (25%) among the OCA1 alleles in Chinese. Through this study, we found that while some of the OCA mutant alleles were identified in other populations, ethnic difference still exists. Hum Mutat 14:542, 1999.

Epstein-Barr virus-encoded latent membrane protein 1 co-expresses with epidermal growth factor receptor in nasopharyngeal carcinoma

Latent membrane protein 1 (LMP-1) is the only Epstein-Barr virus (EBV)-encoded oncogenic protein that has been detected in nasopharyngeal carcinoma (NPC), a cancer that is closely associated with EBV. Previous in-vitro studies have demonstrated that LMP-1 can upregulate epidermal growth factor receptor (EGFR) in epithelial cells. It was not established whether this cellular effect exists in NPC. To assess the association between LMP-1 and EGFR in NPC tissues, 60 NPC specimens were examined by immunohistochemistry using anti-LMP-1 antibody (CS 1-4) and anti-EGFR antibodies (EGFR 1, EGFR 1005). The results revealed that 41 (68.3%) specimens were immunopositive for LMP-1 and 44 (73.3%) specimens over-expressed EGFR. Morphologically, the expressions of LMP-1 and EGFR were homogeneously distributed in the tumor nests. In addition, the correlation between LMP-1 and EGFR was statistically significant (P<0.001, chi2 test, d.f. = 1). To elucidate further the correlation between LMP-1 and EGFR in vivo and in situ, an indirect dual immunofluorescence assay was conducted, using secondary antibodies conjugated with fluorescein isothiocyanate (FITC) or indocarbocyanine (Cy3). The results disclosed an intimate co-expression of LMP-1 and EGFR. In summary, the data indicate that over-expression of EGFR is a common phenomenon in NPC, and that EGFR is co-expressed with LMP-1 in NPC. Thus, EBV may play a role in the tumorigenesis of NPC through the effects of LMP-1 and EGFR.

Echocardiographic flow pattern of patent ductus arteriosus: a guide to indomethacin treatment in premature infants

AIM

To compare the efficacy and safety of an indomethacin treatment strategy based on serial echocardiographic measurement of patent ductus arteriosus (PDA) flow pattern with a standard protocol.

METHODS

Neonates weighing less than 1500 g at birth, who required respiratory support, and who had developed symptomatic PDA, were studied. PDA was confirmed in all infants using colour Doppler echocardiography, and serial observations of the ductal flow pattern were made. Infants randomly assigned to receive conventional indomethacin treatment (protocol group) were given an initial dose of 0.2 mg/kg, followed by 0.1 or 0.2 mg/kg, depending on age, 12 hourly for two further doses, and were eligible for a second course. Those randomly assigned to the ductal flow pattern assessment (ECHO group) received further doses of indomethacin after 24 hours, only if their flow pattern was "pulsatile" or "growing."

RESULTS

There was no significant difference in the primary outcome measures between the two groups. The closure rate was 89.1% and 87.2%, respectively, in the protocol and ECHO groups. The mean (SD) doses of indomethacin were significantly higher in the protocol group: 3.2 (1.4) doses compared with 1.6 (0.9) doses. There was a significantly higher incidence of hypoglycaemia, impaired urine output, and gastrointestinal bleeding in the protocol group.

CONCLUSIONS

An indomethacin treatment strategy for PDA based on measurement of the ductal flow pattern is associated with a reduction in the total doses of indomethacin administered, and a reduced rate of complications, compared with a conventional protocol. There is no difference in closure rate.

MR imaging findings of enteroviral encephaloymelitis: an outbreak in Taiwan

BACKGROUND AND PURPOSE

An outbreak of enterovirus infection occurred in Taiwan from late spring to early fall of 1998. Most of the pediatric infections presented as hand-foot-mouth disease (HFMD) and herpangina. A small portion of patients had symptoms of polio-like encephalitis and paralysis. The purpose of this study was to review the MR imaging findings in CNS involvement of enterovirus infection.

METHODS

Twenty patients who had HFMD and clinical encephalitis were examined with MR imaging. T1-weighted and T2-weighted MR images were obtained. From the rectum, throat, CSF, and peripheral blood, the presence of enterovirus 71 (EV 71) was determined by virus culture, immunofluorescent microscopy, immunologic dot blotting, and reverse-transcription polymerase chain reaction.

RESULTS

MR imaging studies of 20 patients showed hyperintensity in the brain stem and spinal cord in 15 patients, as seen on T2-weighted images. The major CNS lesions were in the medulla oblongata, pons, midbrain, and the dentate nuclei of the cerebellum. In some cases, the lesions involved the spinal cord (three cases) as well as the thalamus (two cases) and putamina (one case). Five patients had normal MR imaging results. After the appropriate management for tachycardia and tachypnea, 18 patients recovered within 1 to 2 weeks. In the follow-up MR imaging examination of five patients, the lesions completely disappeared within 2 weeks to 2 months. In two patients who were still respirator-dependent, MR imaging showed the tissue destruction in the posterior portions of the medulla, pons, and the ventral horns of cervical spinal cord. In one patient, most of midbrain was damaged. The presence of EV 71 was detected in specimens from 18 patients.

CONCLUSION

Because EV 71 was identified in 18 patients, and no other virus was detected, EV 71 was determined to be the major causative agent of this encephalomyelitis. Brain stem and cervical spinal cord involvement are characteristic findings of enteroviral encephalomyelitis.

3-hydroxy-3-methylglutaric aciduria presenting with Reye like syndrome: report of one case

We report the case of a patient with 3-hydroxy-3-methylglutaric aciduria who presented with a repeat attack of Reye like syndrome clinically. Vomiting and somnolence, generalized tonic and clonic convulsions with hepatomegaly, hyperammonemia, liver function impairment, and mild metabolic acidosis were the presenting signs. 3-hydroxyisovaleric, 3-methylglutaric, 3-methylglutaconic and 3-hydroxy-3-methylglutaric acids were detected in the urine by gas chromatography-mass spectrometry. 3-methylglutarylcarnitine was also identified in the urine by fast atom bombardment and tandem mass spectrometry. Therefore, the possibility of metabolic disease should be considered in neonates and infants with repeat attacks of Reye like syndrome and a history of similarly affected siblings.

Agnathia in one of heterozygous twins

Agnathia is a rare developmental field complex in humans with the structural defects limited to the craniofacial region. This rare complex can occur in combination with holoprosencephaly and situs inversus. Here we report on a pair of twins. The female infant had characteristic malformation complex of agnathia, while her twin brother showed normal appearance eventually. This case is the first reported case of isolated agnathia in twins.

Requirement for cell-to-cell contact in Epstein-Barr virus infection of nasopharyngeal carcinoma cells and keratinocytes

Two nasopharyngeal carcinoma (NPC) cell lines and one keratinocyte cell line could be infected with Epstein-Barr virus (EBV) by cocultivation with virus-producing cells but not by cell-free virus. Using porous culture inserts to manipulate the cell-to-cell contact, we demonstrated that contact between EBV donor B cells and EBV recipient epithelial cells was required for the infection. Cell-to-cell contact not only provided a CR2-independent route of infection but also enhanced CR2-mediated infection in a synergistic manner. Activity of two EBV promoters (Cp and Wp) and expression of EBNA2 were detected in the infected population. A small proportion of the infected cells spontaneously entered an EBV lytic state, which could be induced prominently by chemical treatment. This study provides information on how EBV may infect epithelial cells in vivo, such as at the onset of NPC development.

Molecular characterization of secretor type alpha(1, 2)-fucosyltransferase gene deficiency in the Philippine population

We analyzed the seven mutations which are responsible for the deficiency of the secretor type alpha(1,2)-fucosyltransferase gene product, Se enzyme, in the Philippine population. One hundred and one unrelated Filipinos in Taiwan were studied. A new mutation, a 3-base pair deletion from nt 688 through 690, was found in two (0. 1%) of 202 chromosomes. The frequencies of six other mutated alleles were as follows: 71/202 (35.2%) were cDNA 385 A-->T missensed mutation (se2), 28/202 (13.9%) were C571T nonsense mutation (se3), 16/202 (7.9%) were G849A nonsense mutation (se4), 4/202 (1.9%) were G428A nonsense mutation (se1), and 81/202 (40.1%) were wild-type allele (Se). No C628T nonsense mutations (se5) or fusion genes of pseudogene and FUT2 gene (se 6) were found in this population. For the molecular basis of phenotype Le(a+ b-): eight cases had se2/se2, six cases had se2/se3, two cases had se3/se4, one case was homozygous of se4, one case was se3/se1, and two cases were se2/se7. For the Le(a+ b+) phenotype: four cases had se2/se2, two cases had se2/se3, one case was se3/se3, and one case was se2/se4. For the Le(a- b+) phenotype: 16 cases were Se/Se, 21 cases were Se/se2, six cases were Se/se3, five cases were Se/se4, and two cases had Se/se1. Our results suggest that the genotypes of the alpha(1, 2)-fucosyltransferase gene in phenotypes Le(a+ b+) and Le(a+ b-) are the same. Other factors that play important roles may cause the differences between these two phenotypes. Several hotspot mutations in the alpha(1,2)-fucosyltransferase gene are responsible for the nonsecretor phenotype.

Effects of veratrine and paeoniflorin on the isolated rat aorta

The interactions and mechanisms between veratrine and paeoniflorin on the isolated rat aorta were studied. Veratrine (1x10(-6) to 1x10(-4) g/ml) could induce contraction on the isolated rat aorta in a concentration-related manner. Paeoniflorin had no effect on the isolated rat aorta. Pretreatment with prazosin (1x10(-6) M) and nifedipine (1x10(-6) M) but not yohimbine (1x10(-5) M) could decrease the tension of contraction induced by veratrine (1x10(-4) g/ml). Sodium nitroprusside (1x10(-4) M) could inhibit the contraction induced by veratrine (1x10(-4) g/ml) with or without endothelium, whereas methylene blue (5x10(-5) M) could increase the contraction induced by veratrine (1x10(-4) g/ml). Treatment with veratrine (1x10(-4) g/ml) could decrease the tension of contraction induced by norepinephrine (1x10(-6) M) or phenylephrine (1x10(-4) M). The inhibition of veratrine on norepinephrine-induced contraction was potentiated by L-arginine (1x10(-4) M) and reversed by L-NAME (1x10(-5) M). Paeoniflorin (1x10(-4) M) could decrease the tension of contraction induced by veratrine (1x10(-4) g/ml) and methylene blue (5x10(-5) M). The inhibition of paeoniflorin on veratrine was more potent on rat isolated aorta with endothelium than without endothelium. Ryanodine (1x10(-5) M) and Ca2+ -free medium could inhibit methylene blue-induced contraction. From the above results, the relaxation of veratrine on the norepinephrine-induced contraction might be related to the increase of NO and cGMP. The contraction of veratrine on the isolated rat aorta was via the increase of intracellular calcium which was inhibited by paeoniflorin.

Molecular analysis of secretor type alpha(1,2)-fucosyltransferase gene mutations in the Chinese and Thai populations

BACKGROUND

The human Lewis histo-blood group system belongs to a family of structurally related oligosaccharides. The mutations of fucosyltransferase genes alpha(1,2)-fucosyltransferase (FUT2 or Se) and alpha(1,3/1,4)-fucosyltransferase (FUT3 or Le), are responsible for the polymorphism of Lewis blood group phenotypes. However, a population study of the FUT2 mutation in Chinese and Thais has not yet been done, and there is some controversy about the phenotypes of Le(a+b+) and Le(a+b-).

STUDY DESIGN AND METHODS

One hundred twentyfour Chinese and 70 Thais were phenotyped for Lea and Le(b). DNA samples were studied by polymerase chain reaction and then by a restriction enzyme digestion method to distinguish wild-type and six known mutations. Direct sequencing was done for controls and some uncertain cases.

RESULTS

A new mutation, C302T mutation, was found in 2 of 136 chromosomes in the Thai population; none were discovered in Chinese. The frequencies of the normal and six mutant alleles among Chinese and Thais, respectively, were as follows: 134 (54.0%) of 248 and 58 (41.4%) of 140 were wild-type (Se); 0 of 248 and 2 of 140 (both 1.4%) had the G428A mutation; 120 (48.4%) of 248 and 75 (53.6%) of 140 had the A385T mutation; 2 (0.81%) of 248 and 0 of 140 had the C571T mutation; and 1 (0.4%) of 248 and 3 (2.2%) of 140 had the G849A mutation. Only 1 Chinese (0.4%) of 248 had the C628T mutation, and none had fusion gene mutation.

CONCLUSION

The FUT2 genes encoding for the phenotypes Le(a+b+) and Le(a+b-) are the same. The function and character of the mutant enzyme may play an important role in the phenotype. The methods used in this study are clinically applicable in population studies of the FUT2 gene polymorphism to explore relationships among different ethnic groups and correlations between phenotype and genotype.

Early dexamethasone therapy and blood cell count in preterm infants

OBJECTIVE

To assess the effects of early postnatal dexamethasone therapy on hematologic values in preterm infants.

MATERIALS AND METHODS

We reviewed the hematologic data of 179 preterm infants who participated in a double-blind clinical trial of early postnatal dexamethasone therapy (<12 hours after birth) for the prevention of chronic lung disease. One group (86 infants) received saline and the other group (93 infants) received dexamethasone. Dexamethasone was given intravenously every 12 hours in tapering doses: 0.25 mg/kg on days 1 to 7, 0.12 mg/kg on days 8 to 14, 0.05 mg/kg on days 15 to 21, and 0.02 mg/kg on days 21 to 28. Blood samples were obtained on days 0, 3, 7, 10, 14, 21, and 28. None of the infants received prenatal steroid therapy.

RESULTS

Multiple regression analysis revealed significant differences in the values versus time curves of the white blood cell, neutrophil, lymphocyte, basophil, and eosinophil counts between the two groups. The white blood cell count was significantly higher in the dexamethasone group on days 7 through 14, and this was associated with significantly higher numbers of segmented neutrophils and band forms and significantly lower numbers of lymphocytes and eosinophils. The hematocrit and platelet counts were similar in the two groups throughout most of the trial. Except for platelet count, steroid therapy did not alter the hematologic values for infants with bacteremia.

CONCLUSION

Dexamethasone affects white blood cell, segmented neutrophil, lymphocyte, basophil, and eosinophil counts in neonates. This should be taken into consideration when evaluating preterm infants who are receiving dexamethasone.early dexamethasone therapy; neonatal blood count; preterm infant; respiratory distress syndrome.

P53 codon 72Arg polymorphism is not a risk factor for carcinogenesis in the chinese

The potential association of distinct polymorphism of the tumor suppressor gene p53, with an increased susceptibility to malignant transformation has been reported for various cancers. A polymorphism at codon 72 of p53 results in translation to either arginine (p53Arg) or proline (p53Pro), and recent study showed that Caucasian women with arginine form of p53 are more susceptible to HPV-associated carcinoma of the cervix. To examine whether arginine 72 could be a significant risk factor for tumor development, we used a PCR-based assay to analyze p53 genotypes of patients for several types of carcinoma. No significant difference in the frequency of p53Arg was found between normal and cancer patients, the results showed that the individuals homozygous for arginine variant were not at increased risk for cancer.

Glucose and insulin infusion versus kayexalate for the early treatment of non-oliguric hyperkalemia in very-low-birth-weight infants

Forty very low birth weight (VLBW) infants with non-oliguric hyperkalemia in the first few days after birth were enrolled in this study. They were randomly divided into 2 groups, regular insulin (RI) infusion group and kayexalate resin enema group. Therapy was administered when serum potassium level was greater than 6 mEq/L. None of these infants received blood transfusion during this study course. In RI group (n = 20), the ratio of infusion glucose to regular insulin was 10-15 gm glucose to 1 unit RI, and the glucose infusion rate was maintained at least 6 mg/Kg/min. In Kayexalate group (n = 20), the dose of Kayexalate was 1 gm/Kg body weight given rectally every four hours. All treatment discontinued after the serum potassium level returned to normal for 6 hours. The mean gestational ages were 27.4 +/- 1.8 weeks in RI group and 28.4 +/- 2.4 weeks in Kayexalate group, respectively. Mean birth weights were 935 +/- 259 gm (RI) and 1065 +/- 214 gm (Kayexalate). The ages at onset of hyperkalemia were 24.6 +/- 8.2 (RI) and 22.2 +/- 8.1 (Kayexalate) hours after birth. The mean urine outputs during the 8-hour interval prior to development of hyperkalemia were 5.4 +/- 1.3 (RI) and 5.5 +/- 0.9 (Kayexalate) ml/kg/min. The durations of hyperkalemia were 26.4 +/- 14.9 (RI) and 38.6 +/- 13.3 (Kayexalate) hours. The peak serum potassium levels during therapy were 7.3 +/- 0.9 and 7.4 +/- 0.6 mEq/L. The incidences of grade II and above intraventricular hemorrhage (IVH) were 15% (3/20) and 50% (10/20). The incidences of cardiac dysrhythmia were 5% (1/20) and 10% (2/20). Significantly shorter duration of non-oliguric hyperkalemia and lower incidence of IVH were noted in RI group, but there were no differences in the peak potassium level or the incidence of cardiac dysrhythmia between these two groups. We conclude that to use early continuous regular insulin infusion therapy for the treatment of non-oliguric hyperkalemia in VLBW infants is more effective than kayexalate in decreasing the duration of hyperkalemia and reducing the incidence of intraventricular hemorrhage.