Perirenal fat thickness as a predictor of postoperative complications after laparoscopic distal gastrectomy for gastric cancer

Background

Laparoscopic distal gastrectomy is used widely in surgery for gastric cancer. Excess visceral fat can limit the ability to dissect the suprapancreatic region, potentially increasing the risk of local complications, particularly pancreatic fistula. This study evaluated perirenal fat thickness as a surrogate for visceral fat to see whether this was related to complications after laparoscopic distal gastrectomy.

Methods

Perirenal fat thickness was measured dorsal to the left kidney as an indicator of visceral fat in patients with gastric cancer who underwent laparoscopic distal gastrectomy. Patients were divided into two groups: those with and those without complications. The relationship between perirenal fat thickness and postoperative complications was evaluated.

Results

The optimal cut‐off value for predicting morbidity using adipose tissue thickness was 10·7 mm; a distance equal to or greater than this was considered a positive perirenal fat thickness sign (PTS). A positive PTS showed a significant correlation with visceral fat area. Multivariable analysis found that a positive PTS was an independent risk factor for complications (hazard ratio 4·42, 95 per cent c.i. 2·31 to 8·86; P < 0·001).

Conclusion

Perirenal fat thickness as an indicator of visceral fat was an independent predictor of postoperative complications after laparoscopic distal gastrectomy for gastric cancer.

Tuning the type of nitrogen on N-RGO supported on N-TiO2 under ultrasonication/hydrothermal treatment for efficient hydrogen evolution - A mechanistic overview

Efficient hydrogen production through water splitting has been the challenging task to be achieved in the present context of energy crisis. Among the various catalysts employed, nitrogen doped Titanium dioxide/Reduced graphene oxide (N-TiO₂/RGO) nanocomposite has been established to be a promising photocatalytic material for this purpose. However, nuances of doping nitrogen on TiO₂ and the type of nitrogen (pyridinic, pyrrolic and graphitic) stabilized on RGO responsible for facilitating the H₂ production has not yet been addressed mechanistically. In the present investigation, an attempt has been made to synthesise N-Titanium dioxide/N-Reduced graphene oxide (NTNG) nanocomposite under ultrasonication followed by hydrothermal treatment. A stainlesssteel ultrasonic bath, of 6.5 L tank size (LxBxH) 300 × 150 × 150 mm, was used for ultrasonic treatments. The transducers located at the bottom of the ultrasonic bath generate a frequency of 40 kHz with maximum power of 200 W. A mechanism has been proposed including the nuances of formation and the stabilisation of each type of nitrogen on N-RGO as a function of ultrasonication time. The present work supports the stabilization of a given type of nitrogen on RGO through keto enol tautomerism. XPS and FTIR studies have been undertaken to identify the different types of nitrogen doping and the presence of functional groups respectively. XRD, UV-Vis DRS and PL investigations have been made to establish morphological profile and band gap structure of the nanocomposite. It was observed that pyrrolic type nitrogen stabilized on N-RGO augments the efficiency of photocatalytic activity through hydrogen production by water splitting.

Laparoscopic proximal gastrectomy with double-flap technique versus laparoscopic subtotal gastrectomy for proximal early gastric cancer

Background

Laparoscopic proximal gastrectomy with double‐flap technique (LPG‐DFT) and laparoscopic subtotal gastrectomy (LSTG) may replace laparoscopic total gastrectomy (LTG) for proximal early gastric cancer. The aim of this study was to evaluate short‐ and long‐term outcomes after LPG‐DFT and LSTG.

Methods

Patients who underwent LPG‐DFT or LSTG at the Cancer Institute Hospital in Tokyo between January 2006 and April 2015 were included in this retrospective study. Operative procedures were selected based on the distance from the cardia to the proximal boundary of the tumour, tumour location and predicted remnant stomach volume. Patient characteristics, surgical data, markers of postoperative nutritional status, such as blood chemistry and bodyweight loss, and endoscopic findings were compared between procedures. The main study outcome was nutritional status.

Results

A total of 161 patients (LPG‐DFT 51, LSTG 110) were included. Types of postoperative complication occurring more than 30 days after surgery differed between the two procedures. Remnant stomach ulcers, including anastomotic ulcers, were observed only after LPG‐DFT, whereas complications involving the small intestine, such as internal hernia or small bowel obstruction, occurred more frequently after LSTG. Values for total protein, albumin, prealbumin and bodyweight loss were comparable between the two procedures at 36 months after surgery. Haemoglobin concentrations were higher after LPG‐DFT than after LSTG at 24 months (13·4 versus 12·8 g/dl respectively; P = 0·045) and 36 months (13·5 versus 12·8 g/dl; P = 0·007) after surgery. The rate of Los Angeles grade B or more severe reflux oesophagitis was comparable.

Conclusion

LPG‐DFT and LSTG for proximal early gastric cancer have similar outcomes, but different types of complication.

Ultrasonically aided selective stabilization of pyrrolic type nitrogen by one pot nitrogen doped and hydrothermally reduced Graphene oxide/Titania nanocomposite (N-TiO2/N-RGO) for H2 production

Herein, we report the simultaneous doping of nitrogen on TiO₂ and reduced graphene oxide (N-TiO₂/N-RGO) with exclusive stabilization of pyrrolic type nitrogen on RGO network by ultrasonic conditions followed by hydrothermal method for efficient photocatalytic H₂ production. Interestingly, during synthesis of N-TiO₂/N-RGO composite, pyrrolic type nitrogen in RGO has been exclusively stabilized as confirmed by XPS analysis. The exclusive stabilization of pyrrolic nitrogen changed the optical and electronic properties of N-TiO₂/N-RGO nanocomposites by giving two π-electrons to the system for extended conjugation, which enhanced the optical absorption and charge carrier separation efficiency as confirmed by UV-Vis DRS and PL studies. Notably, N-TiO₂/N-RGO nanocomposite demonstrated. This enhanced photocatalytic activity can be ascribed to synergetic action of N-TiO₂ and N-RGO in optical and photogenerated charge carrier separation. Moreover, the plausible mechanism for exclusive stabilization of pyrrolic type nitrogen and enhanced photocatalytic activity were also proposed.

Association between Sarcopenia and Overactive Bladder in Elderly Diabetic Patients

OBJECTIVES

To determine the association between sarcopenia and overactive bladder (OAB) in elderly diabetic patients using the Japanese version of SARC-F called SARC-F-J.

DESIGN

Cross-sectional study.

SETTINGS AND PARTICIPANTS

The study included 329 elderly diabetic patients (aged ≥65 years) who regularly visited the outpatient clinic at Community hospital in Japan.

MEASUREMENTS

The condition of OAB was evaluated using the OAM symptom score, which involves a self-administered questionnaire, and sarcopenia was evaluated using the self-administered SARC-F-J questionnaire comprising five items. The odds ratio for OAB due to sarcopenia was calculated using multiple logistic regression analysis, with OAB as the dependent variable and sarcopenia as the explanatory variable.

RESULTS

A total of 329 patients (186 males, 143 females) were included for analysis in the present study. Of these patients, 22.9% had sarcopenia and 18.7% had OAB. After adjusting the variables, the odds ratio for OAB due to sarcopenia was 4.46 (95% confidence interval [CI], 1.14-17.36, P = 0.031) and 2.09 (95% CI, 0.52-8.26, P = 0.293) for males and females, respectively.

CONCLUSION

This study found that sarcopenia was significantly associated with OAB in elderly diabetic male patients based on SARC-F-J. Moreover, the possibility of the development of OAB should be considered during the medical examinations of elderly diabetic male patients with sarcopenia.

Clinical efficacy of anti-IL-5 monoclonal antibody mepolizumab in the treatment of eosinophilic otitis media

OBJECTIVE

Eosinophilic otitis media (EOM) is an intractable otitis media characterized by a highly viscous effusion containing eosinophils, and it is mostly associated with bronchial asthma. Recently, anti-IL-5 therapy using mepolizumab has been reported to be effective for patients with severe and refractory eosinophilic bronchial asthma. EOM shows accumulation of eiosinophils in the middle ear effusion and most EOM patients have high numbers of peripheral blood eosinophils. Therefore, we carried out a retrospective study to determine whether anti-IL-5 therapy is also effective in the treatment of EOM.

PATIENTS AND METHODS

Nine patients with EOM associated with bronchial asthma received the anti-IL-5 agent mepoliumab as an add-on therapy for at least 6 months (mepolizumab group). They were evaluated by EOM severity scores, symptom scores, bone conduction hearing levels, and surrogate markers before and after receiving the anti-IL-5 therapy. Thirteen EOM patients associated with bronchial asthma who did not receive the anti-IL-5 therapy were also included as controls (control group).

RESULTS

The severity scores of most patients in the mepolizumab group were dramatically reduced at 3 months after the initiation of this therapy and, as therapy continued, they further decreased to levels significantly lower than the baseline. However, two patients with a granulation type of EOM showed minimal improvement from the therapy. The severity scores of control patients showed no significant changes during the study period. Significant deterioration of the bone conduction hearing levels was not observed in either group. The number of peripheral blood eosinophils was significantly reduced, and eosinophils were scarcely observed in the middle ear effusion and middle ear mucosa after the mepolizumab therapy.

CONCLUSIONS

Anti-IL-5 therapy using mepolizumab was effective at inhibiting eosinophilic recruitment to the middle ear in patients with EOM. However, this therapy showed minimal effect on patients with the granulation type of EOM. Therefore, this therapy may be a viable treatment option for refractory EOM without severe mucosal change.

Randomized clinical trial comparing standard diet with perioperative oral immunonutrition in total gastrectomy for gastric cancer

BACKGROUND

Total gastrectomy for gastric cancer is associated with excessive weight loss and decreased calorie intake. Nutritional support using eicosapentaenoic acid modulates immune function and limits catabolism in patients with advanced cancer, but its impact in the perioperative period is unclear.

METHODS

This was a randomized phase III clinical trial of addition of eicosapentaenoic acid-rich nutrition to a standard diet in patients having total gastrectomy for gastric cancer. Patients were randomized to either a standard diet or standard diet with oral supplementation of an eicosapentaenoic acid (ProSure®), comprising 600 kcal with 2·2 g eicosapentaenoic acid, for 7 days before and 21 days after surgery. The primary endpoint was percentage bodyweight loss at 1 and 3 months after surgery.

RESULTS

Of 127 eligible patients, 126 were randomized; 124 patients (61 standard diet, 63 supplemented diet) were analysed for safety and 123 (60 standard diet, 63 supplemented diet) for efficacy. Across both groups, all but three patients underwent total gastrectomy with Roux-en-Y reconstruction. Background factors were well balanced between the groups. Median compliance with the supplement in the immunonutrition group was 100 per cent before and 54 per cent after surgery. The surgical morbidity rate was 13 per cent in patients who received a standard diet and 14 per cent among those with a supplemented diet. Median bodyweight loss at 1 month after gastrectomy was 8·7 per cent without dietary supplementation and 8·5 per cent with eicosapentaenoic acid enrichment (P = 0·818, adjusted P = 1·000). Similarly, there was no difference between groups in percentage bodyweight loss at 3 months (P = 0·529, adjusted P = 1·000).

CONCLUSION

Immunonutrition based on an eicosapentaenoic acid-enriched oral diet did not reduce bodyweight loss after total gastrectomy for gastric cancer compared with a standard diet. Registration number: UMIN000006380 ( http://www.umin.ac.jp/).

Role of Prealbumin as a Powerful and Simple Index for Predicting Postoperative Complications After Gastric Cancer Surgery

BACKGROUND

Preoperative factors, including nutritional status, may have strong correlations with postoperative morbidities. The current study evaluated preoperative prealbumin concentrations as a predictor of postoperative complications after gastric surgery.

METHODS

A retrospective study of 1798 patients who underwent gastrectomy for gastric adenocarcinoma was performed. Information was collected on basic patient characteristics, preoperative laboratory findings, and 30 day postoperative complications. The patients were divided into three groups based on prealbumin concentrations (≥22 mg/dL, <22 to ≥15 mg/dL, and <15 mg/dL) for analysis.

RESULTS

The overall complication rate was 21.7 %, and the infection rate was 16 %. Subgroup analysis based on prealbumin concentrations showed that complication rates were markedly elevated with decreasing concentrations of prealbumin. Multivariate analysis using a logistic regression model showed that both overall and infectious complications were strongly associated with male gender, elevated C-reactive protein (CRP), and decreased prealbumin levels (p < 0.05). Even in patients with a CRP level higher than 0.1 mg/dL, male gender and low prealbumin concentrations (<15 mg/dL) were significantly correlated with overall and infectious morbidities (p < 0.05).

CONCLUSIONS

Preoperative prealbumin concentrations are useful predictors of short-term postoperative outcomes after gastrectomy.

Prognostic and clinical impact of sarcopenia in esophageal squamous cell carcinoma

Recently, depletion of skeletal muscle mass (sarcopenia) has been linked to poor prognosis in several types of cancers, but has not been investigated in esophageal squamous cell carcinoma (ESCC). This retrospective study investigates the relationship between sarcopenia and clinical outcome in ESCC patients treated by surgical resection or definitive chemoradiation therapy (dCRT). The study was retrospectively conducted in a single academic hospital in Kumamoto, Japan, and involved 325 ESCC patients (256 surgical cases and 69 dCRT cases) treated between April 2005 and April 2011. Skeletal muscle mass was quantified by radiologic measures using standard computed tomography scans. The skeletal muscle tissue in the 325 ESCC patients was distributed as follows: mean: 47.10; median: 46.88; standard deviation (SD): 7.39; range: 31.48-71.11; interquartile range, 46.29-47.90. Skeletal muscle tissue was greater in male patients than in female patients (P < 0.0001), but was independent of other clinical and tumor features. Sarcopenia was not significantly associated with overall survival (log rank P = 0.54). Lymph node involvement significantly altered the relationship between sarcopenia and survival rate (P for interaction = 0.026). Sarcopenia significantly reduced the overall survival of patients without lymph node involvement (log rank P = 0.035), but was uncorrelated with overall survival in patients with lymph involvement (log rank, P = 0.31). The anastomosis leakage rate was significantly higher in the sarcopenia group than in the non-sarcopenia group (P = 0.032), but other surgical complications did not significantly differ between the two groups. Sarcopenia in ESCC patients without lymph node involvement is associated with poor prognosis, indicating sarcopenia as a potential biomarker for identifying patients likely to experience an inferior outcome. Moreover, sarcopenia was associated with anastomosis leakage but no other short-term surgical outcome.

Effects of Pt dispersion on electronic and oxide ionic conductivity in Pr1.90Ni0.71Cu0.24Ga0.05O4

The effects of dispersing Pt particles in bulk Pr1.90Ni0.71Cu0.21Ga0.05O(4+δ) (PNCG) on the electrical conductivity and oxygen permeability of the material were studied. The different thermal expansion coefficients of PNCG and Pt generated a mechanical compressive strain in the PNCG. This may cause the electrical conductivity to decrease in samples containing Pt. In contrast, the oxide ion conductivity estimated from the oxygen permeability increased upon dispersion of Pt. These variations appear to be related to the electron hole and interstitial oxygen concentrations. Moreover, the present study suggests that the mechanical strain induces a chemical strain via the introduction of oxygen defects as well as changes in cation valences.

Is it essential to inform the positive donor? A 2-year study in a tertiary care hospital

Background:

In India, screening of blood for human immunodeficiency virus (HIV), hepatitis B surface antigen (HBsAg), and hepatitis C virus (HCV) is mandatory before issue, but the donors are often not informed of their positive status.[1] The positive donors are always kept in dark. Is it essential to inform the positive donor? It is a debate still.

Materials and Methods:

Sri Ramachandra Blood Bank, Chennai, took the challenge of posttest counseling of blood donors from June 2008. Blood collected from donors were screened for HIV, HBsAg, and HCV. The donors of the blood, which are positive by two different enzyme-linked immunosorbent assay for any of the above tests, were sent a letter of calling respecting their rights and maintaining confidentiality. Responded donors were given counseling and offered information about confirmation, evaluation, consultation, early treatment, follow-up, contact testing, and transmission prevention. The results were analyzed for a period of 2 years from June 2008 to May 2010.

Results:

Among the 22,573 donors, 355 (1.7%) were found to be positive in the screening tests. Letters of calling were sent to 310 (87.04%) donors. In all, 218 (70.3%) donors with 7 (87.5%) HIV, 199 (68.85%) HBsAg, and 12 (92.31%) HCV positivity responded. None of the responded donors knew their status earlier. In all, 82 (35%) of them were repeat donors with 201 earlier donations at various blood banks.

Conclusion:

Posttest counseling of positive donors is essential for the health of the donor and his family, prevention of diseases, improving blood bank economy, and reducing exposure to healthcare workers.

Permeability of Nitrobacter agilis to Organic Compounds

Ida, S. (Cornell University, Ithaca, N.Y.), and M. Alexander. Permeability of Nitrobacter agilis to organic compounds. J. Bacteriol. 90:151-156. 1965.-None of a variety of inorganic ions or organic compounds served as a sole energy source for the growth of Nitrobacter agilis, and the test substrates were not oxidized by either intact cells or extracts of the obligate chemoautotroph. The organic substances did not serve as sole carbon sources for the bacterium in a synthetic medium, and they failed to enhance the rate of nitrite oxidation. The organism was permeable to acetate and a number of other simple carbon compounds, however, and exogenously supplied acetate was converted to a number of products. On the basis of these findings, possible reasons are examined for the inability of the chemoautotroph to use exogenous organic compounds as energy or carbon sources.

Daily bowel movements and Escherichia coli O157 infection

The usual bowel habits of 259 school age children before the large outbreak of E coli O157 infection in Sakai City in the summer of 1996 were investigated. A daily morning movement and/or frequent bowel movements may be a protective factor against infection, while being constipated contributed to a worsening of symptoms.

[Evaluation of the new pump for home parenteral nutrition Terumo Cafty]

This study was undertaken to evaluate the usefulness of 'Cafty' which is a new infusion pump system for administering home parenteral nutrition (HPN), recently launched by Terumo Corporation. We used 'Cafty' in two patients and found it has more advantages than the existing pump with regard to the following points: 1. Cafty is provided with a display and alarms that indicate pump troubles such as emptiness, occlusion or mis-operation. 2. It is easier to carry because of its smaller size (width 80 mm x length 132 mm x thickness 33 mm) and its lighter weight (320 g). 3. While Cafty operation using a cassette-type tubing and plain control panel to simpler the flow rate accuracy is not reduced. In conclusion, Cafty is better than the existing HPN pump from the viewpoint of safety, portability and easiness.

Mild to severe lithium-induced nephropathy models and urine N-acetyl-beta-D-glucosaminidase in rats

Long-term treatment with lithium induces functional and/or structural disturbances in the kidneys. However, no procedure has been established for the early diagnosis of lithium intoxication. In this study, we prepared mild to severe lithium-induced nephropathy rat models and examined the usefulness of urine N-acetyl-beta-D-glucosaminidase (NAG) for the early diagnosis of lithium-induced renal insufficiency. Lithium was administered by repeated intraperitoneal injection (1, 2 and 4 mEq/kg/day for 10 days). We also measured the plasma creatinine and paraaminohippuric acid (PAH) clearance, and observed renal histological changes. Lithium pretreatment elevated the plasma creatinine level and decreased PAH clearance in a dose-dependent manner. The NAG level in the lithium 4 mEq/kg group was very high. The levels in the lithium 1 mEq/kg and 2 mEq/kg groups were almost the same and were higher than the control group. A histological examination of the kidney revealed glomerular congestion and/or atrophy and tubular expansion in all of the groups except the control group. These histological changes were dose-dependent. In conclusion, urine NAG may be useful in the early diagnosis of renal side effects caused by lithium therapy. When the urine NAG level becomes high in a patient taking lithium for bipolar disorder, the physician may need to consider lithium-induced renal insufficiency.

A 13C-urea breath test in children with helicobacter pylori infection: assessment of eradication therapy and follow-up after treatment

PURPOSE

Our aim was to evaluate the usefulness of the 13C-urea breath test (UBT) for the diagnosis of Helicobacter pylori infection, for assessment of the efficacy of eradication therapy, and for post-treatment follow-up in children.

METHODS

Seventy-two patients who underwent endoscopy for symptoms related to the upper gastrointestinal tract were examined by rapid urease test, histology, and culture. The patients were also studied with serology and UBT.

RESULTS

Forty-seven of the 72 patients were diagnosed with H. pylori infection, based on the results of biopsy-based tests and serology. As an initial diagnostic test to detect H. pylori infection, the sensitivity of the UBT was 95%, which was comparable with that of histology (94%), rapid urease test (96%), and serology (91%) and was greater than that of culture (79%). The specificity of the UBT was 100%, which was comparable with that of the other four tests. The efficacy of eradication therapy was assessed by biopsy-based tests and the UBT in 24 H. pylori-positive patients. For this purpose, the sensitivities of UBT and histology were 100%, while the sensitivities of culture and the rapid urease test were 88%. The specificity was 100% for all of these tests. Eleven patients were assessed by biopsy-based tests and UBT after more than 6 months of post-treatment follow-up. There were no discordances between the results of the UBT and those of the biopsy-based tests in any of the patients.

CONCLUSIONS

The UBT may be useful for detecting H. pylori infection in children with upper gastrointestinal tract symptoms, for assessment of the efficacy of eradication therapy, and for the follow-up evaluation of patients after the therapy.

[Mesial temporal lobe epilepsy in a patient with Wilson's disease receiving FK506 (tacrolimus) after liver transplantation]

Mesial temporal lobe epilepsy (MTLE) developed in a boy receiving FK506 (tacrolimus) after liver transplantation. He had no history of convulsions. At the age of 7, he underwent liver transplantation 13 days after he developed the abdominal form (fulminant hepatitis) of Wilson's disease. On postoperative day 18, he had a generalized tonic seizure (duration 20 min.) with loss of consciousness. FK506 was discontinued under the suspicion of FK506-induced encephalopathy. His symptoms resolved within a few days. FK506 was readministered at 3 months after transplantation. Ten months later, he developed complex partial seizures characterized by right tonic posturing with oral automatism. EEG revealed sporadic spikes in the anterior temporal region. MRI and SPECT showed bilateral (left side dominant) hippocampal lesion, which suggested the diagnosis of MTLE. Since seizures became refractory to medical treatment with progressive worsening of memory functions, FK506 was discontinued again at 36 months after readministration. Six months later, his memory improved remarkably, but there were no changes in seizure frequency and in MRI and SPECT findings. Our findings indicate that FK506 might damage the hippocampus, thereby causing MTLE. Additional case reports, however, will be required to elucidate this new FK506-related neurological complication.

Nitrite reductase gene enrichment improves assimilation of NO(2) in Arabidopsis

Transgenic plants of Arabidopsis bearing the spinach (Spinacia oleracea) nitrite reductase (NiR, EC 1.7.7.1) gene that catalyzes the six-electron reduction of nitrite to ammonium in the second step of the nitrate assimilation pathway were produced by use of the cauliflower mosaic virus 35S promoter and nopaline synthase terminator. Integration of the gene was confirmed by a genomic polymerase chain reaction (PCR) and Southern-blot analysis; its expression by a reverse transcriptase-PCR and two-dimensional polyacrylamide gel electrophoresis western-blot analysis; total (spinach + Arabidopsis) NiR mRNA content by a competitive reverse transcriptase-PCR; localization of NiR activity (NiRA) in the chloroplast by fractionation analysis; and NO(2) assimilation by analysis of the reduced nitrogen derived from NO(2) (NO(2)-RN). Twelve independent transgenic plant lines were characterized in depth. Three positive correlations were found for NiR gene expression; between the total NiR mRNA and total NiR protein contents (r = 0.74), between the total NiR protein and NiRA (r = 0.71), and between NiRA and NO(2)-RN (r = 0.65). Of these twelve lines, four had significantly higher NiRA than the wild-type control (P < 0.01), and three had significantly higher NO(2)-RN (P < 0.01). Each of the latter three had one to two copies of spinach NiR cDNA per haploid genome. The NiR flux control coefficient for NO(2) assimilation was estimated to be about 0.4. A similar value was obtained for an NiR antisense tobacco (Nicotiana tabacum cv Xanthi XHFD8). The flux control coefficients of nitrate reductase and glutamine synthetase were much smaller than this value. Together, these findings indicate that NiR is a controlling enzyme in NO(2) assimilation by plants.

Acid exposure stimulates the adherence of Streptococcus pneumoniae to cultured human airway epithelial cells: effects on platelet-activating factor receptor expression

To examine the effects of acid exposure on the adherence of Streptococcus pneumoniae to cultured human tracheal epithelial cells, cells were exposed to acid at various pH levels, and various concentrations of S. pneumoniae were added to the culture medium. The number of S. pneumoniae adhering to cultured human tracheal epithelial cells increased after acid exposure. Y-24180, a specific inhibitor of the receptor for the platelet-activating factor (PAF) and PAF itself decreased the number of S. pneumoniae adhering to cultured human tracheal epithelial cells after acid exposure. Acid exposure increased the activation of transcription factor nuclear factor (NF)-kappa B and the expression of protein and messenger RNA (mRNA) of the PAF receptor. The pyrrolidine derivative of dithiocarbamate (PDTC), an inhibitor of NF-kappa B, also decreased the number of S. pneumoniae adhering to the cultured human tracheal epithelial cells after acid exposure. Acid exposure increased the content of interleukin (IL)-1 alpha and IL-1 beta in the culture supernatants, but monoclonal antibodies to IL-1 alpha and IL-1 beta failed to inhibit the increased number of S. pneumoniae adhering to cultured human tracheal epithelial cells after acid exposure. These findings suggest that acid exposure stimulates the adherence of S. pneumoniae to the airway epithelial cells via increases in PAF receptors. Increases in PAF receptor expression may be, in part, mediated via activation of transcription factors and subsequent PAF receptor mRNA expression by acid exposure. Increased adherence of S. pneumoniae may be one of the reasons why pneumonia develops after gastric juice aspiration.

Rapid and simple phenotypic assay for drug susceptibility of human immunodeficiency virus type 1 using CCR5-expressing HeLa/CD4(+) cell clone 1-10 (MAGIC-5)

We describe a rapid and simple novel phenotypic assay for drug susceptibility of human immunodeficiency virus type-1 (HIV-1) using a CCR5-expressing HeLa/CD4(+) cell clone 1-10 (MAGIC-5). MAGIC-5 cells produced large amounts of HIV-1 in culture supernatants, which enabled us to perform the phenotypic resistance assay. Determination of HIV-1 susceptibility to various protease inhibitors (PI) and nucleoside reverse transcriptase inhibitors was completed within 15 days in T-cell-tropic (X4) and macrophage-tropic (R5) viruses using fresh plasma samples containing at least 10(4) copies/ml. The nucleotide sequence of the envelope V3 region of HIV-1 in plasma was almost identical to that of the virus isolated by MAGIC-5 cells, suggesting a lack of selection bias in our assay. The assay variability was confined to within five-fold in all drugs examined. Accordingly, we used a 10-fold increase in the 50% inhibitory concentration as the cutoff value for viral resistance in the present assay. HIV-1 resistant to lamivudine, which was not detected by conventional genotypic assays, was isolated. In HIV-1 with PI-associated primary amino acid substitutions, our assay showed that drug resistance profiles correlated well with previously reported genotypic-assay data. Furthermore, our assay provided comprehensive results regarding PI resistance in the presence of multiple mutations. The novel assay successfully quantified the level of resistance of clinical HIV-1 isolates to a battery of anti-HIV drugs, indicating its clinical usefulness, particularly in patients who failed to respond to antiretroviral chemotherapy.

Prospective study of mother-to-infant transmission of hepatitis C virus

BACKGROUND

Mother-to-infant transmission of hepatitis C virus (HCV) could become the main route of HCV infection in the future because there are no methods available to prevent vertical infection. The aim of this study was to determine the incidence of mother-to-infant transmission in infants born to mothers who tested positive for anti-HCV antibodies and to elucidate associated risk factors for transmission.

METHODS

Screening was conducted for 16,800 pregnant women with an anti-HCV antibodies test, and 154 mothers were positive. From the positive group 141 mothers were enrolled in the study and their 147 infants were followed from birth for serum alanine aminotransferase activity, anti-HCV antibodies and HCV RNA. HIV infection was tested in 73 of 141 mothers, all of whom were negative.

RESULTS

Thirty-three infants were dropped from the study because they were followed for <6 months or were not tested adequately. Of the 114 infants finally evaluated 9 (7.8%) had detectable HCV RNA. The transmission rate was not influenced by the mode of delivery [vaginal delivery, 8 of 90 vs. cesarean section, 1 of 24 (P = 0.396)] or by the type of feeding [9 of 98 for breast-fed infants vs. 0 of 16 for formula-fed infants (P = 0.243)]. All infected infants were born to mothers who had HCV viremia at the delivery (P = 0.040) and to those with a high viral load (P = 0.019).

CONCLUSIONS

Our prospective study showed that the transmission rate of mother-to-infant HCV infection was 7.8% in anti-HCV antibody-positive mothers. Risk was related to the presence of maternal HCV viremia at delivery and a high viral load in the mothers.

Extrasolar planets

The first known extrasolar planet in orbit around a Sun-like star was discovered in 1995. This object, as well as over two dozen subsequently detected extrasolar planets, were all identified by observing periodic variations of the Doppler shift of light emitted by the stars to which they are bound. All of these extrasolar planets are more massive than Saturn is, and most are more massive than Jupiter. All orbit closer to their stars than do the giant planets in our Solar System, and most of those that do not orbit closer to their star than Mercury is to the Sun travel on highly elliptical paths. Prevailing theories of star and planet formation, which are based on observations of the Solar System and of young stars and their environments, predict that planets should form in orbit about most single stars. However, these models require some modifications to explain the properties of the observed extrasolar planetary systems.

Two cases of persistent hyperinsulinemic hypoglycemia that showed spontaneous regression and maturation of the Langerhans islets

Near-total pancreatectomy has been recommended as the treatment for persistent hyperinsulinemic hypoglycemia (PHH) in infants. However, recently there has been a report described that one third of 95% pancreatectomy failed to prevent hypoglycemia and more than two thirds had diabetes ultimately. The authors experienced 2 cases of PHH, which raise a query about the extensive pancreatectomy. Case 1: A female patient who manifested PHH shortly after birth underwent less extensive pancreatectomy twice at age 2 months and 8 years. After each operation, her clinical symptoms regressed, and she became free from the disease eventually. Histologic findings showed nesidioblastosis in which the islets clearly matured. Case 2: A male infant with PHH had an absolute indication for pancreatectomy. However, after a meticulous control of the blood glucose level with parenteral nutrition followed by continuous enteral nutrition feeding combined with medication, he became free from the disease. The current cases show there exist cases of PHH in which the islets mature and symptoms regress spontaneously. Therefore, we conclude near-total pancreatectomy is not always the treatment of choice. As an alternate strategy, long-term controlled feeding and medication combined with or without less extensive pancreatectomy should be considered with the expectation of spontaneous regression.

Four cases of bleeding diathesis in children due to congenital plasminogen activator inhibitor-1 deficiency

Congenital plasminogen activator inhibitor-1 (PAI-1) deficiency is an extremely rare disorder characterized by a bleeding diathesis that begins in childhood due to hyperfibrinolysis as a result of decreased PAI-1 activity. We now present 4 unrelated pediatric cases of congenital PAI-1 deficiency. All 4 patients had a history of recurrent episodes of subcutaneous bleeding beginning in early childhood. These episodes were characterized by abnormal prolonged bleeding after trauma, tooth extraction, and surgical procedures, as well as by rebleeding following initial hemostasis. The 2 female patients both had symptoms compatible with hypermenorrhea. The family history was positive in 2 of the 4 patients. Hemostatic screening studies in all 4 patients revealed no abnormalities. Testing for factor XIII antigen, von Willebrand factor antigen, ristocetin cofactor activity, alpha(2)-plasmin inhibitor (alpha2PI) activity, and plasminogen activity was normal. The euglobulin lysis times were shortened in all cases as compared with those in normal control subjects. None of the patients had elevated tissue plasminogen activator (tPA) antigen levels, but PAI activity was markedly decreased in all cases. Three of the patients also had reduced levels of PAI-1 antigen. There tended to be a reduction in tPA-PAI-1 complex in all cases. In addition, 2 patients had elevated PIC (plasmin-alpha2PI complex). Tourniquet tests were performed in 2 patients, with no appreciable rise in PAI-1 activity or PAI-1 antigen levels. The administration of tranexamic acid clearly improved hemorrhagic symptoms in these patients. We considered PAI-1 deficiency to be the likely etiology of the congenital bleeding diatheses in these 4 cases.

Effects of lithium on the pharmacokinetics of valproate in rats

Combined treatment with lithium and valproate has been used for bipolar disorder. However, the studied interaction between these two drugs has not been fully investigated. We therefore examined the effects of lithium on the pharmacokinetics (plasma disappearance, metabolism and urinary excretion) of valproate in rats. Lithium (2 mEq kg(-1)) was administered intraperitoneally twice a day for ten days. Plasma disappearance curves of valproate (50 mg kg(-1), i.v.), valproate-metabolizing activities of UDP-glucuronosyltransferase (UGT) and cytochrome P450 (CYP) in liver microsomes and urinary excretion of free valproate and valproate-glucuronide were examined. The metabolizing activity of UGT and CYP were determined by enzyme assays and a fluorescence polarization immunoassay system. Urinary valproate-glucuronide was obtained using this system by subtracting the free level from total level, which was determined after deconjugating the sample with heat and NaOH. The half-life of plasma disappearance of valproate was 25% reduced by lithium pretreatment (0.428 +/- 0.031 h with repeated lithium pretreatment vs 0.578 +/- 0.062 h for controls). The valproate-metabolizing activity of UGT and CYP were not altered by lithium although lithium increased the urinary excretion of valproate-glucuronide. In conclusion, lithium pretreatment causes a decrease in plasma valproate levels and an increase in urinary excretion of valproate-glucuronide in rats.

[A two-year follow-up of zidovudine plus lamivudine combined with indinavir in antivival naive HIV-infected patients]

Efficacy of a 3-drug combination (Zidovudine (AZT) + Lamivudine (3TC) + Indinavir (IDV)) has been evaluated in 17 anti-viral naive patients with HIV infection for 24 months. Our genotypic resistance assay was able to analyze more than 80% of the patients whose viral load (VL) was over 3,000 copies/ml. This therapy was continued in 11 patients (65%) for 24 months. Among them, VL was undetectable (VL < 400 copies/ml) in patients at 24 month (47% by intent-to-treat, 72% by on treatment). Of the 11 patients, a 3TC resistance-related mutantion was detected in only one case. The therapy was discontinued in 6 cases. Main reasons of the discontinuation were side effects. However, if the therapy was switched to other combinations when VL was undetectable, VL remained undetectable in 5 cases at 24 month.

Reduction in interleukin-2-producing cells but not Th1 to Th2 shift in moderate and advanced stages of human immunodeficiency virus type-1-infection: direct analysis of intracellular cytokine concentrations in CD4+ CD8- T cells

Previous studies have suggested that CD4+ T lymphocytes shift from the Th1 type to the Th2 type during disease progression in patients with the human immunodeficiency virus type-1 (HIV-1). In the present study, we used a modified method that allowed a direct measurement of intracellular cytokines in CD4+ CD8- T cells. A total of 48 HIV-1-infected (HIV+) and 16 HIV-1-uninfected (HIV-) individuals were studied. The percentages of CD4+ CD8- T cells producing interleukin-2 (IL-2), interferon-gamma (IFN-gamma), interleukin-4 (IL-4), or interleukin-5 (IL-5) in HIV+ and HIV- subjects were 23.6% versus 34.9% (P < 0.01), 13.7% versus 13.2%, 1.3% versus 1.0%, and 1. 2% versus 0.9%, respectively. The population of IL-2-producing cells decreased proportionately with reductions in CD4 counts (< 200/mm3, 200-500/mm3, and > 500/mm3 to 18.0%, 23.5%, and 30.5%, P < 0.05, respectively). There was an inverse correlation between the percentage of IL-2-producing cells and plasma viral load (r = - 0. 446, P < 0.05). However, the percentages of CD4+ CD8- T cells producing other cytokines were not different between HIV+ and HIV-. Our cross-sectional study demonstrated a decrease in IL-2-producing cells but not the Th1 to the Th2 shift in the CD4+ CD8- T cell population in the moderate and advanced stages of HIV-1-infection.

[Usefulness of MT-2 assay to decide when to start anti-HIV therapy]

It is well known that the emergence of syncytium inducing (SI) variant correlates accelerated CD4 decline and disease progression during the course of HIV infection. We have conducted a clinical study to investigate whether or not detection of SI by MT-2 cells (MT-2 assay) can be a clinical marker to decide when to start anti-HIV therapy since 1995. We examined 483 blood samples obtained from 172 HIV-infected patients by the MT-2 assay. SI was detected from 20 patients. There were five untreated patients whose CD4 counts were 300/microliter or more. Anti-HIV combination therapies were started soon after detection of SI in all of them. We have followed their clinical courses for more than 4 years, so far, in three of them. Their CD4 counts and clinical courses were both stable. In contrast, in another patient who could not receive any anti-HIV therapy even though SI positive, decline of CD4 was very rapid (200/microliter/year) and the disease progressed to AIDS within one year as like other SI positive cases before the era of several approved anti-HIV drugs. According to these distinct prognosis, the MT-2 assay might be a useful clinical marker for deciding anti-HIV therapy at least in our limited cases.

Genetic alterations in the JAG1 gene in Japanese patients with Alagille syndrome

Alagille syndrome (AGS) is a congenital anomaly syndrome that affects liver, heart, pulmonary artery, eyes, face, and skeleton. Recently, mutations of the JAG1 gene, which encodes a ligand for the Notch receptor, have been identified in AGS patients. We investigated the JAG1 gene for genetic alterations in eight Japanese AGS patients, using fluorescence in situ hybridization (FISH), single strand conformation polymorphism (SSCP) analysis, and direct sequencing. Subtle genetic alterations were identified in six of the eight patients, including three frameshift mutations, two splice donor mutations, and one nonsense mutation. All alleles with identified mutations can be expected to produce non-functional truncated proteins without a transmembrane domain. There was no apparent correlation between the genotypes of the patients and their affected organs, although the phenotypes of the patients with mutations at the splice donor site were found to be less severe.

Preparation of N-alkylated 5-oxo-3-carboxamyl-1,4-thiazinanes on solid support

A general method was developed to generate six-membered cyclic thiazinanes on solid support. Three diversity sites were introduced into this scaffold using primary amines, aldehydes, and 2-bromoalkanoic acids. The methodology to prepare individual cyclic thiazinanes as well as combinatorial libraries of these compounds is described.

Acute effects of griseofulvin on the pharmacokinetics and pharmacodynamics of warfarin in rats

It has been reported that prothrombin time (PT), which is prolonged by warfarin, is reduced when patients on warfarin also take griseofulvin repeatedly. We investigated the cause of the drug interaction and the initial effects of griseofulvin on warfarin pharmacokinetics. Total cytochrome P-450, and the activities of aminopyrine N-demethylase, aniline p-hydroxylase and 7-ethoxycoumarin O-deethylase, after repeated administration of griseofulvin (100 mg/kg orally daily for 5 days) were examined. Acute effects of single doses of griseofulvin (100 mg/kg) on coagulation activity (prothrombin time) and warfarin pharmacokinetics after administration of warfarin were also studied. Repeated administration of griseofulvin induced warfarin-metabolizing enzymes. In contrast, a single administration of griseofulvin increased prothrombin time and serum warfarin concentrations. The activity of a warfarin-metabolizing enzyme (7-ethoxycoumarin O-deethylase) was reduced when griseofulvin was added to rat liver microsomes. The results suggest that reduced warfarin action after repeated administration of griseofulvin may be due to induction of warfarin-metabolizing enzymes, but that there is also an initial increase in warfarin action.

Identification of highly selective inhibitors of collagenase-1 from combinatorial libraries of diketopiperazines

Thiol-containing diketopiperazines have been recently identified as novel heterocyclic inhibitors of matrix metalloproteinase (MMPs). The compounds described had similar activities against the MMPs collagenase-1 and gelatinase-B. An inhibitor that showed greater than 10-fold selectivity for collagenase-1 over gelatinase-B was desired. Previously published work with peptidyl hydroxamates and thiols indicated that while preparing gelatinase selective inhibitors was straightforward, there was not an obvious route to selective inhibitors of collagenase-1. Combinatorial libraries were prepared and evaluated for their ability to inhibit collagenase-1 and gelatinase-B substrate hydrolysis. A method for estimating the IC50 values of compounds generated by high-throughput parallel synthesis aided in the identification of compounds with the desired properties. We have found that thiol diketopiperazines derived from nitrophenylalanine are both potent and selective inhibitors of collagenase-1. In addition, we have demonstrated that combinatorial chemistry can be utilized to identify molecules with a desired selectivity profile without access to the traditional tools of rational drug design.

Active HIV-1 redistribution and replication in the brain with HIV encephalitis

The central nervous system (CNS) is of particular importance in human immunodeficiency virus type 1 (HIV-1) infection. First, the CNS may be difficult to access for anti-retroviral treatment and may become a sanctuary for residual viruses. Second, HIV-1 infection may lead to AIDS dementia complex (ADC) culminating in HIV-1 encephalitis. In order to examine the pattern of drug resistance and the role of encephalitis in enhancing viral redistribution to the CNS, we compared pol gene quasispecies of the spleen and brain in two patients with and two patients without HIV-1 encephalitis, who had been treated with zidovudine (AZT). Although a variable degree of AZT resistance was noted in both the spleen and brain of all patients, phylogenetic analysis indicated that quasispecies developed rather independently in the systemic circulation (spleen) and CNS (brain) of patients without HIV-1 encephalitis, while similar pol gene sequences were obtained from the two compartments of patients with HIV-1 encephalitis. env gene V3 region of patients with HIV-1 encephalitis showed distinct quasispecies in the spleen and brain. Our results suggest that HIV-1 redistribution to CNS is more active in cases with encephalitis and that HIV-1 distributed late to CNS grow actively under certain selective pressure exerted on the V3 region of the env gene.

[Investigation of a new p24 antigen detection system by the chemiluminescence-enzyme-immuno-assay]

We investigated a new p24 antigen detection system by the chemiluminescence-enzyme-immuno-assay (CLEIA) and compared it with the conventional antigen-kits (A; Abbott, B; Coulter). The detection limit of CLEIA, A, and B were 4.3 pg/ml, 11.3 pg/ml, and 5.6 pg/ml, respectively. When the patient's sera and panel sera were examined by the three method, compatible results with the detection limit were obtained. CLEIA can be completed within 35 min, and is performed by an automatic system, which can treat many samples at one time. Therefore, this system is more suitable for screening of donor blood because of the shortening of the window period.

Evaluation of highly sensitive thyrotropin assay for detecting thyroid diseases in neonatal screening: preliminary studies

TSH concentrations in dried blood samples on filter paper were determined by a conventional enzyme-linked immunosorbent assay (ELISA), used for routine neonatal screening for primary hypothyroidism, and a highly sensitive bioluminescence ELISA (BL-ELISA) using firefly luciferase to examine whether central hypothyroidism and hyperthyroidism can be efficiently detected as cases of primary hypothyroidism. Samples were obtained from 3 patients with congenital central hypothyroidism, 5 patients with congenital primary hypothyroidism, 6 patients with hyperthyroidism, 31 neonatal babies with low birth weight (premature babies) and 242 newborn babies with normal birth weight from the general population (normal babies). The TSH values were low in central hypothyroidism and hyperthyroidism. Their deviations from the mean TSH value for normal babies by the BL-ELISA method (-3.12 SD and -4.79 SD in central hypothyroidism and hyperthyroidism respectively) were greater than those by the ELISA method (-2.00 SD and -2.97 SD respectively). The TSH values were high in primary hypothyroidism and normal in premature babies while deviations were the same when BL-ELISA and ELISA were used. These findings indicate that the highly sensitive TSH assay (BL-ELISA) can be used for detecting both primary and central hypothyroidism as well as hyperthyroidism in neonatal screening.

Malonyl alpha-mercaptoketones and alpha-mercaptoalcohols, a new class of matrix metalloproteinase inhibitors

A novel series of matrix metalloproteinase (MMP) inhibitors is described. Incorporation of a terminal alpha-mercaptoketone or alpha-mercaptoalcohol in the zinc binding domain of a series of inhibitors led to compounds exhibiting low nanomolar activity against collagenase-1 (MMP-1), stromelysin (MMP-3), and gelatinase-B (MMP-9).

HIV type 1 V3 variation dynamics in vivo: long-term persistence of non-syncytium-inducing genotypes and transient presence of syncytium-inducing genotypes during the course of progressive AIDS

We performed a population-based sequence analysis of the envelope V3 region of human immunodeficiency virus type 1 (HIV-1) in two infected hemophiliacs. The study was conducted over 6-9 years, extending from the asymptomatic phase to AIDS. In both patients, serial analysis showed that the V3 population at the initial stage consisted exclusively of putative non-syncytium-inducing (NSI) genotypes. Several of these clones continued to be present without change for many years until the terminal stage and often represented the dominant species in the population at each time interval. On the other hand, syncytium-inducing (SI) genotypes were initially absent but appeared shortly before severe depletion of CD4+ T cells and their proportion in the population appeared to correlate with the viral load. In sharp contrast to NSI genotypes, SI genotypes displayed a significantly shorter presence. Thus, rapid gross population changes were found in SI genotypes, which were particularly frequent in the asymptomatic phase and less frequent in the terminal stage. Furthermore, the ratio of nonsynonymous nucleotide substitutions per synonymous substitutions in the V3 region in SI genotypes was higher than the corresponding value of NSI genotypes and the phylogenetic tree analysis revealed that a longer branch length was observed in SI genotypes than in NSI genotypes. These results suggest that there might be a stronger pressure for selection on SI viruses than on NSI viruses during the high CD4 counts on the contrary to the fact that emergence of SI genotypes was well correlated with the rapid decline of CD4 count.

[Home oxygen therapy (HOT) in patients with pulmonary tuberculosis sequelae--comparison between patients medically treated and those surgically treated]

In Japan there are about 40,000 patients under home oxygen therapy (HOT), of whom about 30 to 40% are pulmonary tuberculosis sequelae (TBS). These patients can be divided into three groups depending on the treatments they had, Group 1: those who had medical treatments only, Group 2: those who had artificial pneumothorax, and Group 3: those who had thoracoplasties or other surgical treatments. The purpose of this study was to observe the distributions and possible differences in the survival rates among these groups. The study included 1537 patients with TBS under HOT followed at National Hospitals and Sanatoriums nationwide in Japan. In 819 patients the treatments were specified and of those 354 were in Group 1, 29 in Group 2, and 436 in Group 3, so that the proportion of surgically treated patients in PTS was estimated between 28.4% (436/ 1537) to 53.2% (436/819). The ages at the onset of tuberculosis, at the start of HOT and the intervals in between were 36.6, 66.2 and 29.8 in Group 1, and 26.8, 65.5, and 38.1 in Group 3 respectively. Though the ages at the start of HOT were the same, those at the onset of tuberculosis were about ten years younger in Group 3 than in Group 1. Comparing Group 1 and 3, the survival rates after the initiation of HOT (Kaplan-Meier method) was better in Group 2 (surgically treated) than in Group 1 (medically treated). It is speculated that the reason could be a better preservation of the function of the remaining lung in the surgically treated and a higher incidence of obstructive impairments in the medically treated patients.

Purification and characterization of rhesus monkey liver amido hydrolases and their roles in the metabolic polymorphism for E6123, a platelet-activating factor receptor antagonist

We previously showed that a polymorphism for E6123 [(S)-(+)-6- (2-chlorophenyl)-3-cyclopropanecarbonyl-8,11-dimethyl-2,3,4,5- tetrahydro-8H-pyrido[4',3':4,5]thieno[3,2-f][1,2,4]triazolo[4,3-a] [1,4]diazepine] metabolism exists only in rhesus monkeys. In the present study, we purified, from rhesus monkey hepatic microsomes, three amido hydrolases that are involved in the metabolic polymorphism. Two forms of amido hydrolase from an extensive metabolizer and one from a poor metabolizer were purified by Q-Sepharose Fast Flow, Red A-agarose, octylamino-Sepharose 4B, and hydroxyapatite-Ultrogel chromatography, after solubilization with Lubrol. The three purified enzymes had the same molecular mass (47 kDa), and their amino-terminal amino acid sequences were identical. The enzymes were different from various known carboxylesterases in terms of substrate specificity, molecular mass, and amino-terminal amino acid sequence. They resembled arylacetamide deacetylase from human hepatic microsomes with respect to molecular mass and amino-terminal amino acid sequence. The KM values of the high and low affinity enzymes in the extensive metabolizer and the sole enzyme in the poor metabolizer were 37.6, 73.0, and 76.5 microM, respectively. The Vmax values were 3312.4, 504.8, and 427.9 pmol/min/mg of protein, respectively. The high affinity enzyme in extensive metabolizer appears to be quite distinct, whereas the low affinity enzyme in extensive metabolizer in similar or identical to the sole enzyme in poor metabolizer. Thus, the metabolic polymorphism in rhesus monkey may depend upon the existence of the high affinity enzyme in extensive metabolizer.

Cloning and nucleotide sequence of a leaf ferredoxin-nitrite reductase cDNA of rice

A ferredoxin-nitrite reductase (EC 1.7.7.1) cDNA was isolated and sequenced from a lambda gt 11 cDNA library constructed from nitrate-induced greening shoots of rice (Oryza sativa L.) seedlings. The nucleotide sequence of the cDNA clone contains an open reading frame of 1788 nucleotides. There exists a strong bias for the third codon usage of G/C (95.5%) as in the case of the maize enzyme. The deduced amino acid sequence shows an overall homology to the maize (81%) and the dicot enzymes (70-74%), suggesting that the primary structure of ferredoxin-nitrite reductase is highly conserved in higher plants.