[Imaging features of developmental stenosis of atlas with degenerative cervical myelopathy].

Objective: To investigate the imaging features of patients with developmental stenosis of atlas (small atlas) complicated with degenerative cervical myelopathy and to explore the diagnostic criteria of small atlas. Methods: The clinical data of patients with degenerative cervical myelopathy treated by posterior cervical laminoplasty and resection of posterior arch of atlas from 2006 to 2020 in the Department of Orthopedics, Peking University Third Hospital were retrospectively analyzed. Sixteen cases had spinal cord compression at C1 level after the exclusion of ossification of cervical posterior longitudinal ligament (OPLL) and other pathology. These cases were suspected small atlas (small atlas group). Forty-six cases without posterior arch resection in the same period were selected as control group. The middle sagittal diameter of atlas and the vertical distance from posterior tubercle of atlas to occipitoaxial line under CT in both groups were compared. The sagittal diameter of the spinal canal at the atlas level under MRI, the Japanese Orthopaedic Association (JOA) score for functional state of cervical spine before operation and at last follow-up were also measured. Results: There were 9 males and 7 females in the small atlas group, aged (63±12) years. There were 21 males and 25 females in the control group, aged (57±10) years. The patients in both group were followed-up for at least one year. The sagittal diameter of atlas in the small atlas group was (26.4±3.1) mm, which was significantly smaller than that in the control group [(29.6±2.2) mm, P=0.010]. The vertical distance from the posterior tubercle of atlas to the occipitoaxial line in the small atlas group was larger than that in the control group[(6.79±1.17) mm vs (5.57±1.29) mm, P=0.001]. The diameter of atlas canal in the small atlas group was (8.25±1.44) mm which was significantly smaller than that in the control group [(13.00±1.66) mm, P<0.001]. The JOA score of the small atlas group before operation and at the last follow-up were both slightly lower than that in the control group (both P<0.05), but there was no significant difference in the recovery rate of JOA score between the two groups (61.9% vs 66.0%, P=0.066). Among the 16 cases in the small atlas group, 5 cases of occipital-axial connection were located at the posterior 1/3 of the posterior arch of atlas, and 11 cases of occipital-axial connection were completely located at the posterior arch of atlas. Conclusions: The effective sagittal diameter of atlas is smaller in small atlas group which can lead to more severe cervical myelopathy. The presence of a small atlas should be highly suspected when the sagittal diameter of atlas canal is less than 26 mm under CT. The existence of the small atlas should be alert when the occipitalaxial line is located at the dorsal 1/3 or behind of the posterior arch of atlas.

[Quantitative analysis of the degeneration of cervical spine and the correlation to the heterotopic ossification after artificial cervical disc replacement].

Objective: To investigate parameters related to quantifying the amount of degeneration in preoperative patients to identify ideal indication of artificial cervical disc replacement (ACDR) in patient with a minimum of 10 years of follow-up data. Methods: From January 2004 to August 2008, a total of 44 patients underwent single level Bryan cervical disk replacement performed by the same group of surgeons were involved in this retrospective study, and all of the patients in this group had at least 10 years of follow-up data. Heterotopic ossification (HO) was graded in radiographic images by using the McAfee classification. Preoperative degeneration of cervical spine was evaluated in radiographs based on a quantitative"9 points"scoring system. Univariate analysis and multifactor logistic regression were made to identify significant factors. To determine the cut-off points for the significant factors, a receiver operating characteristic (ROC) curve analysis was conducted. Results: The incidence of HO in study group was 61.4%. Based on univariate analysis results, there were significant differences in the scores of disc height, the presence of anterior osteophytes and endplate sclerosis between the HO group and non-HO group (all P<0.05), and the indices were included in the multivariate analysis. According to the logistic regression results, disc height and endplate sclerosis were identified as the independent risk factors for HO(OR(95%CI): 10.801(1.202-97.064), 37.870(1.581-907.237), respectively, both P<0.05). ROC analysis showed the area under the curve (AUC) of disc height and endplate sclerosis were 0.822 and 0.792, respectively. According to the scoring system, the ROC curve indicated that both the optimal cutoff points were 1.5. Conclusion: The incidence of postoperative HO is relatively high among the patients who had more than 10 years follow-up, and the amount of degeneration in the target level before surgery correlated with the incidence of HO.

[The correlation between the severity of uncovertebral joints degeneration and heterotopic ossification after single-level artificial cervical disc replacement].

Objective: To investigate the correlation between the severity of uncovertebral joints degeneration and heterotopic ossification (HO) after single-level artificial cervical disc replacement (ACDR). Methods: From January 2005 to January 2016, 70 patients who had undergone single-level ACDR in Peking University Third Hospital and had at least 5 years follow-up were included in this study. There were 35 males and 35 females with an average age of (42±8) years (range, 25-62 years). Cervical spine A-P X-rays were taken to assess the degeneration of uncovertebral joints and lateral X-rays were taken to assess the degeneration of intervertebral space. Cervical spine lateral and the flexion-extension X-rays at 5 years follow up were taken to assess HO. Degeneration of uncovertebral joints were evaluated by the classification system set-up in Peking University Third Hospital. Kellgren&Lawrence grading system was used to evaluate the degeneration of intervertebral space. HO was evaluated by the McAfee grading standards. The data were collected before surgery and at 5-years follow-up, then the correlation between degeneration of uncovertebral joints, degeneration of intervertebral space and HO was analyzed with Spearman non-parametric test. Results: The average follow-up time of 70 patients was (62.7±4.8) years (range, 52-74 months). There was a significant positive correlation between preoperative uncovertebral joints degeneration and HO after ACDR (r=0.585, P<0.01). There was a significant positive correlation between preoperative intervertebral space degeneration and HO (r=0.557, P<0.01). There was a significant positive correlation between preoperative intervertebral space degeneration and preoperative uncovertebral joints degeneration (r=0.727, P<0.01). Conclusion: There is a significant positive correlation between preoperative uncovertebral joints degeneration and HO after ACDR.

[Surgical treatment of severe congenital cervical kyphosis].

Objective: To investigate the surgical treatment of severe congenital cervical kyphosis. Methods: The clinical data of patients with severe congenital cervical kyphosis (Cobb>40°) treated in Peking University Third Hospital from March 2004 to March 2018 were retrospectively summarized. In this series, 8 cases were enrolled, included 4 males and 4 females; the patients were 5-45 years old. According to the etiology, 4 patients were diagnosed with vertebral body underdevelopment, 2 with vertebral insufficiency, 1 with cervical spine congenital fusion and 1 with C(2) spinous process mecism. Five cases were treated with traction before final surgical correction. The surgical strategy was anterior correction or posterior correction or combined procedure in regards to different situation. The curvature of cervical angle was measured by two-line Cobb method, and the cervical kyphosis angle was measured on lateral radiographs in the neutral and extended position at the pre-operation and post-operation in each patient. The correction rate and evaluated Japanese Orthopedic Association (JOA) scoring for the function of spinal cord were also measured. The data before and after the operation were compared with t test. Results: In this series, the average kyphotic Cobb angle was 67°±18° and 8°±8° before and after surgical correction, respectively (t=8.471,P<0.05).The final correction rate was 87%±13%.The JOA score improved from 11.1±2.7 to 14.0±1.5 (t=-2.656, P<0.05) at the end of follow up. Conclusions: The pre-correction by cervical spine traction and final surgical correction by anterior, posterior or combined approaches of internal fixation and fusion can achieve good results and reduce risk and difficulty in operation for severe congenital cervical spine kyphosis with vertebral body underdevelopment without vertebral insufficiency and cervical spine congenital fusion. The final surgical correction by one-stage anterior, posterior or combined approaches of internal fixation and fusion can achieve good results for severe congenital cervical spine kyphosis with vertebral insufficiency and/or cervical spine congenital fusion.

Half-Century Ammonia Emissions From Agricultural Systems in Southern Asia: Magnitude, Spatiotemporal Patterns, and Implications for Human Health.

Much concern has been raised about the increasing threat to air quality and human health due to ammonia (NH3) emissions from agricultural systems, which is associated with the enrichment of reactive nitrogen (N) in southern Asia (SA), home of more than 60% the world's population (i.e., the people of West, central, East, South, and Southeast Asia). Southern Asia consumed more than half of the global synthetic N fertilizer and was the dominant region for livestock waste production since 2004. Excessive N application could lead to a rapid increase of NH3 in the atmosphere, resulting in severe air and water pollution in this region. However, there is still a lack of accurate estimates of NH3 emissions from agricultural systems. In this study, we simulated the agricultural NH3 fluxes in SA by coupling the Bidirectional NH3 exchange module (Bi-NH3) from the Community Multi-scale Air Quality model with the Dynamic Land Ecosystem Model. Our results indicated that NH3 emissions were 21.3 ± 3.9 Tg N yr-1 from SA agricultural systems with a rapidly increasing rate of ~0.3 Tg N yr-2 during 1961-2014. Among the emission sources, 10.8 Tg N yr-1 was released from synthetic N fertilizer use, and 10.4 ± 3.9 Tg N yr-1 was released from manure production in 2014. Ammonia emissions from China and India together accounted for 64% of the total amount in SA during 2000-2014. Our results imply that the increased NH3 emissions associated with high N inputs to croplands would likely be a significant threat to the environment and human health unless mitigation efforts are applied to reduce these emissions.

[Midterm clinical outcomes and radiological results of surgical treatment for Hirayama disease].

OBJECTIVE: To assess the midterm clinical and radiological outcomes of internal fixation and fusion for the treatment of Hirayama disease and to evaluate the clinical significance and value of this procedure. METHODS: In the study, 36 patients were treated with anterior cervical internal fixation and fusion. The clinical outcomes including muscle strength and atrophy were recorded. The radiological outcomes including range of motion of cervical spine and the cross-sectional area of spinal cord at each level on MRI scan were measured before and at 3 month, 1 year and 2 years follow-up time points after surgery. RESULTS: (1) Clinical outcomes: all the patients showed no further progression of symptoms except one patient with mild progression of muscular weakness and atrophy. As the time passed by, the ratio of the patients with muscle strength and atrophy improvement increased. There were 26.5% of patients in 3 months, 36.0% in 1 year and 85.7% in 2 years who experienced muscle strength improvement. 8.8% of patients in 3 months, 24.0% in 1 year and 35.8% in 2 years felt muscle atrophy improvement. And 12 of the 14 patients showed improved muscle strength and atrophy at the end of 2 years period follow-up. (2) Radiological outcomes: the range of motion (ROM) of C2-C7 was significantly decreased after the operation. The ROM of preoperation was 62.25°±2.10° and that of 2 years postoperation was 13.67°±7.51°(P<0.01). The spinal cord was of no compression on flexion MRI. The cross-section area of spinal cord on MRI was significantly increased only at C6 level (P<0.05) at the end of three months follow-up. The level of increased cross-section area rose to C4-C5-C6 levels (P<0.01) in 1 year and to C4-C5-C6-C7 levels at the end of 2 years follow-up (P<0.05). The cross-section area increased 15.60% at C4, 19.08% at C5, 21.60% at C6 and 23.91% at C7 with significant difference (P<0.05) 2 years after the operation. CONCLUSION: Anterior cervical internal fixation and fusion is an effective surgical treatment for Hirayama disease and may provide preferable midterm clinical and radiological outcomes. This procedure has clinical significance and value in terms of control of the progression and outcome of this disease.

Correlation between polymorphisms in the visfatin gene and its expression in the serum and coronary artery calcification.

We investigated the association between serum visfatin levels and single nucleotide polymorphisms (SNPs; rs61330082, rs2058539) in the visfatin gene and coronary artery calcification (CAC) in patients from Wenzhou, China. CAC patients (N = 206) were divided into two groups: mild CAC (MCAC) and moderate and severe CAC (MSCAC). Volunteers without CAC (N = 70) were included in the control group. The serum visfatin level was analyzed by enzyme-linked immunosorbent assay. SNPs (rs61330082, rs2058539) in the visfatin gene were analyzed by polymerase chain reaction-restriction fragment length polymorphism. Clinical data, serum visfatin levels, and genotype and allele frequencies of rs61330082 and rs2058539 were compared among the three groups. MSCAC patients expressed significantly higher serum visfatin levels (30.58 ± 6.12 ng/mL) than individuals in the MCAC (29.03 ± 1.87 ng/mL) and control (24.45 ± 5.44 ng/mL) groups (P < 0.05). The genotype distributions and frequencies of rs61330082 differed significantly among the groups (P < 0.05), while those of rs2058539 did not. The serum visfatin level was positively correlated with the body mass index (BMI), high-density lipoprotein cholesterol (HDL-C), and insulin resistance index (IRI), and negatively correlated with the triglyceride (TG) levels (P < 0.05) of patients. Serum visfatin is associated with the development of CAC. The T allele of the rs61330082 SNP in the visfatin gene had a cardioprotective effect on patients with CAC; the SNP at rs2058539 was not significantly associated with CAC. The BMI, HDL-C, IRI, and TG levels influenced the development of CAC.

[Reoperation for cervical myelopathy duo to progressing ossification of the posterior longitudinal ligaments in patients with expansive laminoplasty].

OBJECTIVE: To retrospectively analyze the clinical data of the patients with reoperation for cervical myelopathy due to progressing ossification of the posterior longitudinal ligaments, with previous open-door expansive laminoplasty, and to evaluate the outcomes. METHODS: From May 2006 to July 2012, a retrospective study was performed on a consecutive series of 17 patients with previous open-door expansive laminoplasty, who had received the reoperation for cervical myelopathy due to progressing ossification of the posterior longitudinal ligaments. The reoperation was performed based on the clinical manifestations and segments of responsibility. The anterior approaches were performed in 12 cases, and the posterior approaches in 5 cases. The correlation between the clinical factors and Japanese Orthopedic Association (JOA) scores or the JOA recovery rate was evaluated by Pearson or Spearman correlation test. The pre- and post-operative JOA scores were analyzed by repeated measures ANOVA and the JOA recovery rates were compared with paired t test. RESULTS: The mean follow-up was 137.5 months (range 60-348 months). There were no serious complications after surgical procedures. There was one case that had C5 palsy in the first operation and had recovery after one week. Another case had C5 palsy in the reoperation with posterior approach, which had recovery at the end of 6 months postoperation. Three cases had the cerebrospinal fluid leakage of the reoperation, with two cases in the anterior approaches and one case in the posterior approach. There was no significant correlation between the clinical variables and JOA scores or JOA recovery rates. The JOA scores of the patients in the first operation were improved from 9.4±4.1 to 12.8±2.8 (P<0.01), and the JOA recovery rate was 45.6%. The JOA scores of the reoperation were improved from 10.2±2.8 to 12.7±2.4 (P<0.05) at the end of 6 months and 14.3±1.9 (P<0.01) by the last follow-up. There were significant differences between the JOA recovery rates by the last follow-up (63.2%) and at the end of 6 months (39.3%) of the reoperation or 45.6% of the first operation (P<0.01). CONCLUSION: The reoperation for cervical myelopathy duo to progressing ossification of the posterior longitudinal ligaments can significantly promote the recovery of the spinal cord, based on the clinical manifestations combined with segments of responsibility of the imaging.

Enterocin TW21, a novel bacteriocin from dochi-isolated Enterococcus faecium D081821.

AIMS: Purification and characterization of a novel bacteriocin produced by strain Enterococcus faecium D081821. METHODS AND RESULTS: Enterococcus faecium D081821, isolated from the traditional Taiwanese fermented food dochi (fermented black beans), was previously found to produce a bacteriocin against Listeria monocytogenes and some Gram-positive bacteria. This bacteriocin, termed enterocin TW21, was purified from culture supernatant by ammonium sulfate precipitation, Sep-Pak C18 cartridge, ion-exchange and gel filtration chromatography. Mass spectrometry analysis showed the mass of the peptide to be approximately 5300·6 Da. The N-terminal amino acid sequencing yielded a partial sequence NH2 -ATYYGNGVYxNTQK by Edman degradation, and it contains the consensus class IIa bacteriocin motif YGNGV in the N-terminal region. The open reading frame (ORF) encoding the bacteriocin was identified from the draft genome sequence of Enterococcus faecium D081821, and sequence analysis of this peptide indicated that enterocin TW21 is a novel bacteriocin. CONCLUSIONS: Enterococcus faecium D081821 produced a bacteriocin named enterocin TW21, the molecular weight and amino acid sequence both revealed it to be a novel bacteriocin. SIGNIFICANT AND IMPACT OF STUDY: A new member of class IIa bacteriocin was identified. This bacteriocin shows great inhibitory ability against L. monocytogenes and could be applied as a natural food preservative.

Isolation and characterization of lactic acid bacteria from yan-tsai-shin (fermented broccoli stems), a traditional fermented food in Taiwan.

AIMS: To isolate, characterize and identify lactic acid bacteria (LAB) in yan-tsai-shin (fermented broccoli stems), a traditional fermented food in Taiwan. METHODS AND RESULTS: A total of 226 LAB were isolated; 111 cultures were isolated from samples collected from seven different markets and 115 from six fresh broccoli samples. These isolates were characterized phenotypically and then initially divided into nine groups (r1 to r9) using restriction fragment length polymorphism analysis and sequencing of 16S ribosomal DNA. Some isolates were further divided into four additional groups by other genetic analysis. The most common bacterial genera in yan-tsai-shin and fresh broccoli were Weissella, Lactococcus and Lactobacillus. Regional similarities in the LAB, with differences in diversity, were observed in this study. On the basis of phylogenetic analysis of 16S rRNA, rpoA, rpoB and pheS gene sequences, two strains were included in the genera Enterococcus and Lactococcus, respectively, and identified as potential novel species or subspecies. In addition, the novel enterococcal strain, and 33 L. lactis subsp. lactis and two Weissella cibaria strains were found to have bacteriocin-like inhibitory substance (BLIS) producing abilities. CONCLUSIONS: These results suggest that the LAB play important roles in the fermentation of yan-tsai-shin. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report describing the distribution and varieties of LAB existing in yan-tsai-shin and fresh broccoli. In addition, two potential novel LAB species or subspecies and one potential novel BLIS were also found in this study.

Weissellicin L, a novel bacteriocin from sian-sianzih-isolated Weissella hellenica 4-7.

AIM: To identify and characterize novel bacteriocins from Weissella hellenica 4-7. METHODS AND RESULTS: Weissella hellenica 4-7, isolated from the traditional Taiwanese fermented food sian-sianzih (fermented clams), was previously found to produce a bacteriocin active against Listeria monocytogenes and some other Gram-positive bacteria. Bacteriocin activity decreased slightly after autoclaving (121°C for 15 min), but was inactivated by protease K and trypsin. Mass spectrometry analysis revealed the bacteriocin mass to be approximately 3205·6 Da. N-terminal amino acid sequencing yielded a partial sequence, NH2 -KGFLSWASKATSWLVGP, by Edman degradation. The obtained partial sequence showed high homology with leucocin B-TA33a; however, at least two different residues were observed. No identical peptide or protein was found, and this peptide was therefore considered to be a novel bacteriocin produced by W. hellenica 4-7 and termed weissellicin L. CONCLUSIONS: The findings obtained in the current study suggest a novel bacteriocin produced by W. hellenica 4-7. SIGNIFICANCE AND IMPACT OF THE STUDY: Bacteriocins from Weissella remain rare, and this study is the second report of a bacteriocin produced by W. hellenica.

Screening and characterization of LAB-produced bacteriocin-like substances from the intestine of grey mullet (Mugil cephalus L.) as potential biocontrol agents in aquaculture.

AIM: To isolate and characterize bacteriocin-like inhibitory substance (BLIS)-producing lactic acid bacteria from the intestine of grey mullet. METHODS AND RESULTS: Inhibitory activity against at least one or more indicator strains was observed in one Enterococcus thailandicus, one Enterococcus faecium and two Lactococcus garvieae strains. Enterococcus faecium B3-8 and Ent. thailandicus B3-22 showed the greatest inhibitory activities against Listeria monocytogenes ATCC 19111 and were therefore further characterized. The results suggested that the inhibitory substances from the two strains showed similar characteristics with respect to sensitivity to heat and proteolytic enzymes. BLIS from Ent. thailandicus B3-22 was characterized by a broader inhibitory spectrum than that from Ent. faecium B3-8. SDS-PAGE revealed that the molecular size of partially purified BLISs from Ent. faecium B3-8 and Ent. thailandicus B3-22 was c. 5 and 3 kDa, respectively. The molecular mass of purified bacteriocin from Ent. thailandicus B3-22 was further determined to be 6319 Da by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The results indicated that BLIS from Ent. thailandicus B3-22 can effectively inhibit the growth of all tested L. garvieae strains. CONCLUSIONS: The findings obtained in this study suggest the potential use of Ent. thailandicus B3-22 as a biocontrol agent against pathogenic L. garvieae in the aquaculture. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report describing the characteristics of BLIS from Ent. thailandicus that showed potential for use as a biocontrol agent in the aquaculture.

Sequence of a cloned pR72H fragment and its use for detection of Vibrio parahaemolyticus in shellfish with the PCR.

The nucleotide sequence of pR72H cloned from Vibrio parahaemolyticus 93 was determined. We examined all V. parahaemolyticus gene sequences published in the GenBank-EMBL databases for homology and found that no other DNA sequence of V. parahaemolyticus was highly homologous to the sequence reported in this study. A pair of primers, VP33-VP32, derived from a pR72H fragment were selected to detect V. parahaemolyticus. The sensitivity of PCR detection for a pure culture of V. parahaemolyticus was 10 cells from crude bacterial lysates. Furthermore, a detection level of 2.6 fg, equivalent to 1 cell, was obtained by using purified chromosomal DNA as the template. The expected PCR products were obtained from all V. parahaemolyticus strains tested (n = 124), while no PCR amplicons were found in other vibrios or related genera (n = 50). High levels (10(6) to 10(10) CFU/ml) of Escherichia coli cells did not affect the PCR assay sensitivity. The presence of 10(8) V. parahaemolyticus cells or 10(9) E. coli cells in the PCR mixtures completely inhibited the PCR. When oyster samples were inoculated with V. parahaemolyticus 93 and cultured in tryptic soy broth containing 3% NaCl for 3 h at 35 degrees C, an initial sample inoculum level of 9.3 CFU/g was detected in a PCR assay with crude bacterial lysates. The PCR assay with enrichment culturing in salt polymyxin broth was compared with the conventional method for naturally contaminated shellfish and fish samples. We conclude that this PCR assay with enrichment culturing is a good alternative method for the detection of V. parahaemolyticus.

Rapid and specific detection of the thermostable direct haemolysin gene in Vibrio parahaemolyticus by the polymerase chain reaction.

Synthetic oligonucleotide primers derived from a sequence of the thermostable direct haemolysin (tdh) gene were used in a polymerase chain reaction (PCR) amplification technique to detect this gene in strains of Vibrio parahaemolyticus. A total of 36 TDH-producing, and 89 TDH-negative Vibrio parahaemolyticus strains and 46 other vibrios and enteric pathogens were studied. In all, 36 strains of Vibrio parahaemolyticus from which the tdh gene could be successfully amplified by PCR were found to be TDH-positive in TDH haemolysin assay. No amplification products were obtained from Vibrio parahaemolyticus strains that were TDH-negative in the haemolysin assay or from other vibrios and enteric pathogens, with the exception of two strains. The PCR results were consistent with DNA hybridization tests. The detection limit for the tdh gene by PCR amplification was 40 pg of total DNA, or broth culture containing 1000 viable cells. Amplification products were confirmed by restriction enzyme digestion and Southern blot hybridization. The PCR method could detect the tdh sequences in stool samples from patients with gastroenteritis caused by V. parahaemolyticus. This PCR protocol clearly identified TDH-producing strains of V. parahaemolyticus and provides an alternative to conventional methods for TDH detection by research laboratories, clinical laboratories, regulatory agencies, and the seafood industry.

Chromosome aberrations reduced in whole-body irradiated mice by pretreatment with cyanide.

Male mice exposed to single, whole-body 60Co irradiation, were injected intraperitoneally with a non-toxic dose of KCN, 2 min or 20 min prior to irradiation. Bone-marrow cells were examined for chromatid breaks and chromosome aberrations (CA) at different times post-irradiation. The 2 min but not the 20 min treated mice had a marked reduction in chromatid breaks and chromosome aberrations. A study was made of mice exposed to 3.0 Gy (1.8 Gy/min), treated with KCN 2 min prior to irradiation and examined 5 min to 30 d post-irradiation. After 5 min there were no significant changes in frequency of CA. Subsequently, the incidence of CA in the KCN-treated group was reduced compared to the irradiated controls. By the 30th day, however, CA frequencies had returned to control levels in all groups. No effect of KCN treatment was observed in the white or red blood cells. The cytogenetic results were posited to be a function of the relative inhibition and recovery times of cyanide affected cytochrome oxidase, DNA synthesis, and ATP.

Diversity of the promoting action of cyclosporine on the induction of murine lymphoid tumors.

We have previously demonstrated that cyclosporine (CsA), a powerful immunosuppressant, enhanced the development of thymic lymphomas in Swiss Webster mice initiated with a single subcarcinogenic dose of N-methyl-N-nitrosourea and enhanced the spontaneous development of thymic tumors in AKR mice. In the present study, we examined whether the initiation of mice with a single dose of gamma-radiation modified the target cell specificity of the CsA promotion of lymphoma induction. Male Swiss Webster and C57B/6 mice were divided into four groups. The mice in group 1 and 2 of both strains were given a single dose (350 rad) of gamma-radiation; 10 days thereafter group 1 was given a basal diet and group 2 a basal diet containing 0.015% CsA for 25-35 weeks. Groups 3 and 4 consisted of control mice without radiation and were maintained on a basal or a CsA diet. None of the mice in either strain in groups 1, 3 and 4 developed tumors. Eighteen out of 39 (46%) Swiss Webster mice that received radiation followed by a CsA diet developed tumors involving mesenteric lymph nodes and the spleen. The tumor cells had immunoglobulins on their surface and were negative for Thy 1, suggesting lymphomas of B cell lineage. Four mice (10%) developed thymic tumors which were positive for Thy 1. Seven of 14 (50%) C57B/6 treated with radiation and CsA developed thymic tumors, while none developed tumors of B cell lineage. The results indicate that CsA is a potent promoter of the induction of lymphomas in mice and that the cell type is determined by the type of initiating agents and the strain of mice.

Anaplastic carcinomas in nude mice and in original donor strain rats inoculated with cultured oval cells.

Male Sprague-Dawley rats were fed for 4-5 weeks a choline-devoid diet containing 0.1% DL-ethionine. Preparations of nonparenchymal epithelial cells, enriched in oval cells, were isolated from the livers of these animals and were placed in culture. Six lines of hepatic epithelial cells were thus established. The lines underwent transformation after several passages, became tumorigenic in nude mice and 3 lines also in rats of the same strain of origin of the isolated cells. The tumors were uniformly highly anaplastic carcinomas. Preliminary morphologic, cytologic, and cytochemical results were consistent with the tumoral cells being hepatocytelike cells. These findings are viewed and discussed in terms of the cellular source, in vivo, of longterm cultures of rat liver epithelial cells, and in relation to a possible role of hepatic nonparenchymal epithelial cells in the process of hepatocellular tumor induction by chemical carcinogens.

Induced acute non-lymphocytic leukemia following long-term chemotherapy: a study of 20 cases.

Twenty individuals developed acute non-lymphocytic leukemia (ANLL) following long-term chemotherapy for other disorders. The primary disorders included non-Hodgkin's lymphoma (five), Hodgkin's disease (five), carcinoma (four), multiple myeloma (three), chronic leukemia (two), and rheumatoid arthritis. Leukemia developed from 11-132 months (mean approximately 60 months) following institution of chemotherapy and all cases have occurred since 1974. Pre-leukemic cytopenias were present in 15 individuals. Fifteen of the 20 patients had chromosome analyses and 14 were abnormal. The leukemia was invariably refractory to chemotherapy with a median survival of only two months. Of the patients autopsied, only one individual had any evidence of the primary malignancy. This study illustrates the need for surveillance for secondary ANLL following long-term chemotherapy with/without radiotherapy. Duration of optimal chemotherapy for the primary disease must be determined by control trials and weighed against the risk of developing a secondary leukemia.