An international outbreak of Salmonella infections caused by alfalfa sprouts grown from contaminated seeds

An outbreak of Salmonella serotype stanley infections occurred in the United States and Finland in 1995. The outbreak was investigated through case-control studies in Arizona, Michigan, and Finland; by isolate subtyping; and by tracing and culturing of the implicated food. Alfalfa sprout consumption was the only exposure associated with S. stanley infections in Arizona (matched odds ratio [MOR] = 11.1; 95% confidence interval [CI], 1.4-513), Michigan (MOR = 5.5; CI, 1.6-23), and Finland (MOR undefined; CI, 4.9-infinity). US and Finnish patient isolates were a unique outbreak strain distinct from S. stanley isolates not linked to the outbreak. Alfalfa sprouts eaten by patients in 6 US states and Finland were traced to seed shipped by a Dutch shipper. Thus, it was concluded that alfalfa sprouts grown from contaminated seed caused an international outbreak of > or =242 S. stanley infections in > or =17 US states and Finland. This outbreak illustrates a new mechanism through which contamination of fresh produce can cause large, widely dispersed outbreaks.

[Successful treatment of intraoperative myocardial ischemia with nicorandil]

We report five patients who developed intraoperative myocardial ischemia but were treated successfully with nicorandil. Case 1; An 84 year-old male underwent emergent laparotomy and ileolysis under inhalational plus thoracic epidural anesthesia. During his emergence from anesthesia, arterial pressure and heart rate increased abruptly due to excitement, leading to ST-T depression on V5 lead. Bradycardia and hypotension developed subsequently. Immediately after i.v. injections of nicorandil 4 mg and atropine 0.3 mg, ST-T change and hemodynamics improved dramatically. Case 2; A 67 year-old male underwent esophagectomy under inhalational plus thoracic epidural anesthesia. Following the completion of surgery, elevation of ST-T developed suddenly on lead II, though hemodynamics were not compromised. ST-T elevation disappeared immediately after nicorandil 6 mg and continuous infusion of nitroglycerin (TNG) was initiated. Case 3; A 71 year-old female underwent aortic valve replacement under high-dose fentanyl anesthesia. Shortly after starting cardiopulmonary bypass (CPB), ST-T segment on leads II and V5 was elevated suddenly. This was accompanied by severe pulmonary hypertension suggestive of severe left ventricular failure. Shortly after nicorandil 4 mg via a pulmonary artery (PA) catheter, ST-T segment returned to the baseline and pulmonary arterial pressure was normalized. Case 4; A 61 year-old male underwent coronary revascularization under high-dose fentanyl anesthesia. During weaning from CPB, elevation of ST-T segment occurred on leads II and V5. ST change improved, responding to nicorandil 6 mg en bolus via a PA catheter. Case 5; A 67 year-old male underwent coronary revascularization under high-dose fentanyl anesthesia. He was unable to be weaned from CPB for several hours because of frequent and repeated attacks of ventricular tachycardia and ventricular fibrillation. The arrhythmia did not respond to various kinds of treatments including intra-aortic balloon pumping and continuous infusions of inotropes, anti-arrhythmic drugs and anti-anginal drugs. In spite of repeated intracoronary injections of TNG, graft flow to the left anterior descending branch remained low at 40 ml.min-1. After an intracoronary injection of nicorandil 1 mg, however, blood flow increased to 100 ml.min-1, resulting in a marked reduction in frequency of ventricular arrhythmia. The patient came off bypass successfully. In each case, intraoperative myocardial ischemia was treated successfully with nicorandil. Neither hypotension nor arrhythmia resulted from its bolus injection. Nicorandil might be a useful therapeutic tool for myocardial ischemia during anesthesia.

[Atypical lung abscess occurring in an elderly female suffering from diabetes mellitus--a case report]

We report an atypical case of lung abscess occurring in a 73-year-old female who suffered from diabetes for more than 20 years. In 1993 she had a total gasterectomy for gastric cancer. In 1995 she was admitted to our hospital complaining of a mild cough and a small amount of sputa. A CT scan of the chest revealed a huge abscess in the left lung. Streptococcus sanguis was cultured from the intrathoracic fluid. It is possible that the severe lung abscess in spite of the few symptoms occurs in the compromised host, such as this patient who suffered from diabetes for long time. Oral streptococci in close relationship to misswallowing should be taken into consideration as one of the causes of this condition.

Inhibitory action of (-)-epigallocatechin gallate on radiation-induced mouse oncogenic transformation

The anticarcinogenic activity of a major component of green tea, (-) epigallocatechin gallate (EGCg) was examined by using the radiation-induced oncogenic transformation in C3H10T1/2 cells. EGCg substantially suppressed the radiation-induced transformation so that the transformation frequency with 15 microM of EGCg was reduced nearly to spontaneous levels. This effect of EGCg was in a dose-dependent manner and significant suppression of transformation was observed even in treatment of cells with 5 microM of EGCg concentration where the cytotoxicity was mild. The inhibitory effect of EGCg was maximal when it was present during the entire incubation period. However, neither treatment prior to nor concurrent with radiation was effective, suggesting that EGCg action is mainly involved in the promotional stage of C3H10T1/2 cell transformation.

Uninephrectomy prevents the ischemia-induced increase in renin activity

Contralateral uninephrectomy attenuates unilateral ischemic injury. The present work was performed to elucidate whether the beneficial effect of uninephrectomy was associated with the modification of ischemia-induced changes in plasma or renal renin activity. A 60-min left renal artery occlusion was conducted in right nephrectomized (Nx) and sham-nephrectomized (Sham-Nx) rats. The decline in inulin clearance 48 h after ischemia was significantly less in Nx rats than in Sham-Nx animals (0.50 +/- 0.10 vs. 0.052 +/- 0.029 ml/min/kidney, p < 0.05). Following ischemia, plasma renin activity (PRA) significantly increased in Sham-Nx (from 5.4 +/- 0.9 to 15.5 +/- 1.4 ng AI/ml/min, p < 0.01) but not in Nx (from 3.5 +/- 0.5 to 5.0 +/- 1.0 ng AI/ml/ min) animals. PRA and renal cortical renin content (2,200 +/- 225 vs. 1,257 +/- 187 ng AI/h/mg protein, p < 0.05) were significantly less in Nx rats than in Sham-Nx animals 48 h after renal ischemia. The decrease in body weight was greater in Nx rats than in Sham-Nx animals. Plasma atrial natriuretic peptide (ANP) (195 +/- 30 vs. 302 +/- 40 pg/ml, p < 0.05) and renal dopamine (DA) content (3.2 +/- 0.5 vs. 13.7 +/- 1.3 ng/g tissue, p < 0.01) were rather lower in the Nx group when compared with the Sham-Nx group. No significant difference was found in the intrarenal content of norepinephrine (NE) between two ischemic groups. These findings suggested that uninephrectomy prevents the ischemia-induced increase in renin activity. The prevention of the increase in renin activity in Nx rats is not be mediated through the modulation of ischemia-induced changes in sodium balance, plasma ANP level and/or intrarenal contents of NE and DA.

Differential regulation of gap junction protein (connexin) genes during cardiomyocytic differentiation of mouse embryonic stem cells in vitro

Using an in vitro system for differentiation of embryonic stem (ES) cells into cardiac myocytes, we analyzed the expression of connexin (Cx) genes by RT-PCR to learn what changes in the expression of multiple connexin genes occur during the early stage of heart development. We also examined gap junctional intercellular communication by using Lucifer Yellow dye microinjection transfer, studied intracellular Ca2+ transients by confocal laser image analysis using fluo 3, and determined localization of Cx43 by immunofluorescence during in vitro differentiation of ES cells into cardiac myocytes. The transcripts for Cx43 and Cx45 were detected in undifferentiated ES cells and in embryoid bodies before and after the appearance of beating cardiomyocytes. In contrast, Cx40 transcripts were not observed in undifferentiated ES cells and were barely detectable in 3- and 5-day-old embryoid bodies. Cx40 transcripts significantly increased with the appearance of beating cells similar to those of cardiac-specific genes. Dye coupling was present among undifferentiated ES cells, prebeating cells of embryoid body outgrowth and ES cell-derived beating cardiomyocytes. When dye was injected into a beating cell, dye spread was restricted to neighboring beating cells. Immunofluorescence demonstrated that Cx43 protein was localized not only in beating cells but also in surrounding nonbeating cells, whereas myosin heavy chain alpha/beta was exclusively positive in the beating cells. These data suggest that the expression of multiple connexins is differentially regulated during the cardiomyocytic differentiation of ES cells in vitro and that Cx40 expression may be linked to early stages in cardiomyocytic differentiation.

A novel stilbene glucoside, oxyresveratrol 3'-O-beta-glucopyranoside, from the root bark of Morus alba

A novel stilbene glucoside was isolated from the root bark of Morus alba L. (Moraceae), along with mulberroside A, cis-mulberroside A, oxyresveratrol. The structure of the novel stilbene glucoside was determined as oxyresveratrol 3'-O-beta-glucopyranoside.

The scid mutation does not affect slowly repairing potentially lethal damage that is sensitive to 0.23 M NaCl

The repair of slowly repairing potentially lethal damage (PLD) in radiosensitive cells from the severe combined immunodeficient (scid) mouse was compared with that in Balb/c 3T3 cells with "wild-type" radiosensitivity and that in RD13B2 cells derived from scid cells whose sensitivity is normal because of the presence of fragments of human chromosome 8. Treatment with 0.23 M NaCl was used for fixation of slowly repairing PLD. The scid cells repaired PLD sensitive to 0.23 M NaCl to a great extent whin 3-4 h, similarly to Balb/c 3T3 and RD13B2 cells. This indicates that the scid mutation hardly affects the repair of PLD sensitive to 0.23 M NaCl. On the other hand, as reported previously, the rapidly repairing PLD that is sensitive to 0.5 M NaCl was repaired only slowly (3-4 h) in scid cells, in contrast to the rapid repair (within 1 h) seen with Balb/c 3T3 and RD13B2. This suggests that scid mutation is responsible for this repair at reduced rate. To confirm the independence of repair of 0.23 M NaCl-sensitive PLD from that of 0.5 M NaCl-sensitive PLD, both treatments with 0.23 M NaCl and 0.5 M NaCl were combined in each line. It is found that the repair of either PLD was not affected by the other treatment. The scid mutation impaired only the repair of 0.5 M NaCl-sensitive PLD.

[Botanical origin of commercial samples of traditional Chinese drug xixin (Herba Aasari)]

It has been found out that amony the 158 samples of commercial drug. Xixin (Herba Asari) collected from 28 provinces/cities of China, only three guarters are derived from the species specified in the Chinese Pharmacopoeia and the rest are not. One hundred and eleven samples are derived from Asarum heterotropoides var. mandshuricum and are presently used in 26 provinces/cities, 25 samples are derived from A. himalaicum and used in 10 provinces, the other 22 samples are derived from 9 species such as A. sieboldii, A. forbesii, etc.

Pharmacological properties of traditional medicines. XXII. Pharmacokinetic study of mulberroside A and its metabolites in rat

To identify the active components in Mori Cortex (Chinese medicine), Mori Cortex extracts were administered orally to rats, and then blood plasma, urine, and bile were analyzed. The results showed only a few remaining metabolites of mulberroside A. Consequently, to clarify the transitional properties of mulberroside A derivatives to tissues and the in vivo abundance ratio of mulberroside A compounds, the pharmacokinetics of mulberroside A derivatives were investigated in this study. When Mori Cortex extracts were administered orally, mulberroside A was only detected in small quantities in the plasma, and its bioavailability was about 1%. This is due to the first pass effect, by which most mulberroside A was converted into oxyresveratrol and transported into the circulating blood, and its absorption ratio was estimated at about 50%. Oxyresveratrol was found to be transported to tissues at high rates. As a result, when analyzing the pharmacological activity of the Mori Cortex in vitro, it is more useful to study oxyresveratrol than mulberroside A.

18S ribosomal RNA gene sequences of three Panax species and the corresponding ginseng drugs

Total DNA was extracted from the fresh underground parts of three Panax separate species. The 18S rRNA regions of extracted DNA were amplified by the polymerase chain reaction (PCR) and their sequences were determined. In each species, the sequences were found to be of 1809 base pairs (bps) but with different gene sequences. Different base substitutions were observed at nucleotide positions 497, 499, 501 and 712. The same procedure was performed on commercial samples of Ginseng Radix, Panacis Japonici Rhizoma and American Ginseng. Each sequence completely corresponded with that of each original plant, namely P. ginseng, P. japonicus and P. quinquefolius, respectively. This is the first time that 18S rRNA gene sequencing on Panax species was carried out. Previously, Ginseng drugs have been identified mainly by their external and internal structure. Thus this method will be useful in identifying Ginseng drugs at the gene level.

Prediction of adult height in healthy Japanese children

Longitudinal records from 13,707 children (6749 boys and 6958 girls), aged 6-17 years, were fitted by a smoothing cubic spline function, and the factors influencing changes in height SD score (SDS) during puberty were analysed. Height SDS at 6 years correlated closely with final height SDS. However, short children at 6 years of age tended to increase their height SDS at final height, whereas tall children at the same age tended to decrease their final height SDS for children with the same prepubertal height, the later that pubertal maturation occurred, the greater was the final height achieved. As short children entered puberty relatively late and tall children entered puberty relatively early, height SDS tended to approach 0 SD during puberty. A prediction function obtained by multiple regression analysis using height SDS at 6 years, the percentage by which the child is overweight at 6 years, age at onset of the pubertal growth spurt (PGS) and height at onset of the PGS provides a reasonable model for the prediction of final height SDS without the need to estimate bone age.

Addition of purified prostate specific antigen to serum from female subjects: studies on the relative inhibition by alpha 2-macroglobulin and alpha 1-antichymotrypsin

PURPOSE

Two forms of prostate specific antigen (PSA), 1 complexed to alpha 1-antichymotrypsin and the other a free PSA, are recognized by current commercially available immunoassays. A third form of PSA complexed to alpha 2-macroglobulin also is present in the serum. To study these 3 different molecular forms of PSA in vivo, we simulated leakage of PSA from the prostate into the serum in vitro.

MATERIALS AND METHODS

Purified seminal fluid PSA was incubated with fresh sera from female subjects at different concentrations. Following gel filtration chromatography, the 3 forms of PSA were studied by immunoassays and Western blot analysis.

RESULTS

Using a commercial immunoassay, 60% of immunoreactivity of seminal fluid PSA was lost after incubation with sera from female subjects. Western blot analysis showed that most of this loss in PSA signal was caused by complexation to alpha 2-macroglobulin. Minimal, if any, complexation to alpha 1-antichymotrypsin occurred even when excess alpha 1-antichymotrypsin was added to the serum.

CONCLUSIONS

Our studies demonstrated that alpha 2-macroglobulin is a much stronger inhibitor to PSA than alpha 1-antichymotrypsin. Further studies of these complexes may be important. They clearly explain why spiking PSA into sera from female subjects to be used as quality controls for PSA assays leads only to the free form of enzymatically inactive PSA in the serum, and not to the dominant form of complexed PSA and alpha 1-antichymotrypsin present in human serum.

High level of tritium-remaining in brain of rats exposed to tritiated water as infants

Newborn CD/Crj rats were given tritiated water (HTO) saline i.p. at the dose of 220 microCi (8.14 MBq)/g of B.W. We monitored residual tritium in the sera and organs of male rats up to 26 weeks of age. The total absorbed doses in serum, liver, spleen, testis and brain were estimated to be 3.10, 2.35, 2.43, 2.38 and 2.84 Gy, respectively. Over four weeks of age, a 3-19 times higher tritium content was noted in brain compared to the values of other organs. At 26 weeks of age, testis atrophy was predominant with 20% of control value by relative organ weight in association with decreased spermatogonia and increased Leydig cells. The serum testosterone level was 67% and relative adrenal weight was significantly increased in comparison with the control values. The results indicated that the high accumulation of tritium in brain, destruction of spermatogenesis and feedback of androgenic response were caused by exposure to HTO as infants.

Keio multicenter trial in high-dose interferon-alpha 2b treatment for chronic hepatitis C. Keio Interferon-alpha 2b Study Group

The efficacy of two different high-dose treatment of IFN-alpha 2b was evaluated in this study. Serum hepatitis C virus (HCV) RNA levels were semi-quantified by simplified reverse transcription-polymerase chain reaction. Seventy-one patients with chronic hepatitis C received 10 million units of IFN-alpha 2b daily for 2 weeks or twice a week for 24 weeks. Alanine aminotransferase (ALT) levels overall normalized in 78.1% and 51.6% of the cases at the end of the therapy and 6 months after that, respectively. HCV RNA disappeared in 71.9% and 35.7% of the patients at the end of the therapy and 6 months after that, respectively. There was no significant difference between the 2 different regimes. The efficacy of the treatment was fair in cases in which the pretreatment level of the viral amount was low. The results of this study indicate that daily administration of IFN in the first 2 weeks during 6-month course does not increase the efficacy of the therapy in such a high-dose treatment regime.

[Maze operation for chronic atrial fibrillation with valvular heart diseases]

Between July 1994 and August 1995, 14 patients underwent combined modified maze procedure and valvular surgery including 5 patients having reoperation. Associated procedures were performed with mitral valve operation (n = 13), tricuspid annuloplasty or valve replacement (n = 9) and aortic valve replacement (n = 4). Duration of atrial fibrillation (AF) varied from 1 to 18 years (mean 8.0 +/- 5.8 year), the f-wave voltage ranged from 0.05 to 0.5 mV (0.21 +/- 0.13 mV), left atrial dimension (LAD) ranged from 35.6 to 66.3 mm (49.0 +/- 9.3). One patient died 2 months after undergoing combined maze procedure and MVR + TAP due to pulmonary infection and sepsis, but the other 13 patients survived. Nine patients (69%) regained atrial rhythm, two patients (15%) had junctional rhythm and another two (15%) remained in AF at follow-up periods between 1 to 11.5 months (6.3 +/- 3.1). The nine patients who recovered to normal sinus rhythm had preoperative f-wave for a significant higher voltage than the patients with AF and JR (0.27 +/- 0.12 vs 0.13 +/- 0.05 mV, p < 0.05) and a smaller left atrial dimension (44.5 +/- 0.7 vs 54.8 +/- 6.9 mm, p < 0.05). These data suggest that the maze operation is effective and should be considered for patients with chronic AF indicated for surgical valvular diseases.

Clinical manifestations of HBsAg and anti-HCV negative chronic liver disease in Nagasaki Prefecture, Japan

The discovery of hepatitis C virus (HCV) has enabled the diagnosis of type C chronic liver disease, which had in the past been diagnosed as part of non-A, non-B chronic liver disease. Although most cases with chronic liver disease are caused by hepatitis B virus (HBV) or HCV infection, there are still cases of non-B, non-C chronic liver disease. Forty patients with chronic liver disease, who were seronegative for hepatitis B surface antigen and antibody to HCV, were followed for a mean period of 72 months. The clinical manifestations in these patients were compared with those reported for type B and type C chronic liver disease. Of the 40 patients, 22 were diagnosed with chronic hepatitis, 14 with liver cirrhosis and 4 with hepatocellular carcinoma (HCC). Twenty-seven (67.5%) patients showed mild alanine aminotransferase activity profiles, and the natural clinical course of most patients showed a slow progression compared with that reported for type B and type C patients. The yearly incidence of HCC was 9.7% in patients with liver cirrhosis and 3.9% in chronic hepatitis. These rates were similar to those in type B or type C patients. This suggests that our population sample contained a number of patients with type B, type C or other etiologic agent(s), because 66.7% of the patients who developed HCC had some evidence of exposure to HBV or HCV. Our results suggest that more detailed and accurate tests for detecting HBV and HCV should be considered before making the diagnosis of non-B, non-C chronic liver disease, and that there is the need to reveal unknown etiologic agent(s).

Spontaneous immortalization of cultured skin fibroblasts obtained from a high-dose atomic bomb survivor

Two immortal fibroblastic cell strains (substrains) were established by culturing healthy skin cells obtained from a high-dose atomic bomb survivor (female, age 76 years, 5.14 Gy) for more than 4 years. Designated FM-U and FM-M, the two substrains share the same marker chromosome, t(5q-;6p+), but are karyotypically different, possessing hypodiploid chromosome numbers (39-43) in the former and hypertriploid (69-76) in the latter. Thus far, the two strains have passed through 117 and 156 subcultures or more than 230 and 310 cumulative population doublings, respectively, each passage requiring 4-6 days in the former and 3-4 days in the latter. In the process of immortalization, sequential rearrangement among various chromosomes presumably due to telomeric and interstitial telomeric fusions took place following the telomere shortening, particularly in the senescence and postsenescence phase cells. Of particular interest is the fact that loss of heterozygosity (LOH) of the p53 gene was demonstrated in these immortalized cell populations. In addition, the allelic patterns of the LOH of p53 differed. Further evidence indicative of infinite proliferation was demonstrated in both strains, such as the telomere elongation and the significantly low frequency of cells possessing dicentric chromosomes.

[Early and late results of surgical intervention for 32 active infective endocarditis patients in last 10 years]

Thirty-two active infectious endocarditis patients who underwent 36 surgical procedures (23 NVEs, 13 PVEs) in last 10 years were reviewed. Seven patients (19.4%) died early postoperatively, 3/23 (13%) in NVEs and 4/13 (31%) in PVEs, and the causes of death were LOS in 5, MOF in one and cerebral bleeding in one. NVE patients of double valve deterioration who developed cardiogenic shock had poor operative results, 3 death in 4 (75%) despite of circulatory assist. Aortic PVEs who underwent Danielson's translocation technique also showed 3 death in 4 (75%). Five in 25 survivors (20%) developed late death and 3 of them were related with reinfection of prosthetic valve. We concluded that surgical treatment for active IE provides reasonable results, although they are still challenging for double valve NVEs and aortic PVEs, for which aortic root replacement using homograft would be the procedure of choice.

[Expression of Bcl-2 and Bax in human gastric cancer tissue]

Deregulation of bcl-2 may function as a survival mechanism in cancer cells, predisposed to cell death. Aberrant Bcl-2 expression is a frequent occurrence in chronic atrophic gastritis, gastric epithelial dysplasia and gastric cancer. Inhibition of apoptosis through Bcl-2 expression appears to be specifically associated with promotion of gastric adenocarcinoma. In addition, loss of heterozygosity of the bcl-2 gene is a common event in well-differentiated adenocarcinoma, whereas overexpression of bcl-2 gene is observed in poorly differentiated adenocarcinoma. Bax, a homologue of Bcl-2, counters the death repressor activity of Bcl-2. In our study Bax immunostaining in gastric cancer tissue is not significantly correlated with tumor histology. Possible gene therapy using bax gene is discussed.

Prolonged survival of hamster-to-rat pulmonary xenografts by tacrolimus (FK506) and cyclophosphamide

BACKGROUND

Severe shortage of donor organs in clinical lung transplantation prompted us to investigate the potential use of pulmonary xenografts. The purpose of this study was to determine whether an immunosuppressive regimen of tacrolimus (FK506) and cyclophosphamide would prolong the survival of hamster-to-rat pulmonary xenografts.

METHOD

Left lung transplantation was done with male Golden Syrian hamsters used as donors and inbred male Lewis rats as recipients. Control animals (n = 10) received no immunosuppressive drugs whereas experimental animals (n = 6) were treated with tacrolimus and cyclophosphamide. Tacrolimus was administered intramuscularly at a dosage of 2 mg/kg per day on postoperative days 0 to 4, followed by 1 mg/kg per day on days 5 to 29 and 0.5 mg/kg per day on days 30 to 99. Cyclophosphamide (8 mg/kg per day) was administered orally from the day before transplantation to day 8. After transplantation the animals were monitored by chest radiography. Recipient animals were killed at timed intervals (days 60 and 100) and when the chest radiograph showed complete opacification of the transplanted lung. At necropsy, pulmonary xenografts were examined histologically for evidence of rejection, which was graded on a scale of 0 (no rejection) to 4 (severe rejection). Antihamster lymphocytotoxic antibody titer was also measured in recipient animals after transplantation.

RESULTS

Pulmonary xenografts in the control animals had a median [correction of medium] survival time of 3 days, whereas the median survival in treated animals was more than 74 days. All pulmonary xenografts in control animals had severe rejection on day 3 after transplantation, whereas those in the treated animals had no rejection on days 60 and 100. The lymphocytotoxic antibody titers in control animals increased from 1:16 before operation to 1:4096 on day 3 (p < 0.01). In the treated animals, the lymphocytotoxic antibody titer on day 21 was 1: 8, which was not different from the preoperative value (1:16).

CONCLUSION

These results indicate that a combination of tacrolimus and a short course of cyclophosphamide prolongs the survival of pulmonary xenografts in a hamster-to-rat model.

Determination of the relative neutron sensitivity of a C-CO2 ionization chamber

The neutron sensitivity of a C-CO2 ionization chamber has been experimentally determined in the neutron energy range of 0.1-1.2 MeV. Eleven kU data were obtained which ranged from 0.04 to 0.1 as a function of neutron energy. There were two peaks in the spectrum of the kU factor, and their positions corresponded to the resonance energies of the kerma factors of carbon dioxide, of which the energies are about 0.4 and 1 MeV. The present data agree with the data obtained at the National Institute for Radiological Sciences in Chiba, Japan (NIRS). The energy dependences of the sensitivity were calculated by using the kerma and the W-value ratios of gas to soft tissue for comparison. The experimental data were reproduced well by the calculations.