A comparison of the antibacterial efficacies of essential oils against oral pathogens

Cariogenic bacteria and periodontopathic bacteria are present in dental plaque as biofilms. In this study, we investigated the antibacterial effects of essential oils on the following oral bacteria: Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, Fusobacterium nucleatum, Streptococcus mutans, and Streptococcus sobrinus. We tested manuka oil, tea tree oil, eucalyptus oil, lavandula oil, and romarinus oil and determined their minimum inhibitory concentration and minimum bactericidal concentration. The essential oils inhibited the growth of the bacteria tested, manuka oil being the most effective. Minimum bactericidal concentration values showed that lavandula oil acts bacteriostatically, and the remaining oils, bactericidally. Periodontopathic bacterial strains tested were killed completely by exposure for 30 s to 0.2% manuka oil, tea tree oil or eucalyptus oil. Tea tree oil and manuka oil showed significant adhesion-inhibiting activity against P. gingivalis. All the essential oils tested inhibited the adhesion of S. mutans. This study showed that, among the essential oils tested, manuka oil and tea tree oil in particular had strong antibacterial activity against periodontopathic and cariogenic bacteria. From the viewpoint of safety, we also examined the effects of these essential oils on cultured human umbilical vein endothelial cells and found that, at a concentration of 0.2%, they had little effect on cultured cells.

The TEL/ARG Leukemia Oncogene Promotes Viability and Hyperresponsiveness to Hematopoietic Growth Factors

The TEL/ARG oncogene associated with acute myeloid leukemia is formed by the t(1;12)(q25;p13) reciprocal translocation, which fuses part of the TEL gene to the tyrosine kinase, c-ARG. In an effort to determine the biological effects and investigate signaling of the TEL/ARG fusion protein, multiple sublines of Ba/F3 cells were generated in which a TEL/ARG complementary DNA was expressed under the control of a tetracycline-inducible promoter. Treatment of these cells with doxycycline, a tetracycline analogue, rapidly induced expression of the TEL/ARG protein. TEL/ARG was heavily phosphorylated on tyrosine residues and was also found to rapidly induce tyrosine phosphorylation of multiple cellular proteins, including rasGAP, CBL, STAT5, PI3K, SHP2, Dok, and SHC. The Ba/F3-tet-TEL/ARG cells remained interleukin (IL)-3 dependent without doxycycline but with doxycycline displayed a marked reduction in cell death in the absence of IL-3. TEL/ ARG cells also displayed an enhanced proliferative response to IL-3 and to insulin-like growth factor 1. At least in Ba/F3 cells, although the growth rate was much lower compared to that with IL-3, TEL/ARG appeared to induce some cell proliferation as an immediate consequence. Nonetheless, the hyperresponsiveness to growth factors reported here is more likely to contribute to the pathogenesis of leukemia.

Daily nasal inoculation with the insulin gene ameliorates diabetes in mice

The present study examined the feasibility of liposome-mediated gene transfer via nasal administration, for treating insulin-dependent diabetes mellitus. The rat insulin gene was packed under control of the CMV promoter, complexed with DC-chol/DOPE-based liposomes and administered daily via the nasal route in mice made severely diabetic by streptozocin. Sustained expression of the insulin gene was achieved and insulinopenia, ketonuria and death were prevented. Hyperglycemia and body weight reduction were significantly suppressed without evidence of hypoglycemia throughout the experimental period. RT-PCR and FISH analysis indicated that insulin was produced in the alveolar epithelial cells of the lung. Liposome-mediated in vivo gene transfer via nasal administration may provide an efficacious route for delivery of hormonal and other gene products into the blood stream.

Involvement of periodontopathic biofilm in vascular diseases

Oral bacteria inhabit biofilms, which are firm clusters adhering in layers to surfaces and are not easily eliminated by immune responses and are resistant to antimicrobial agents. Dental plaque is one such biofilm. In the past 10 years, subgingival plaque bacteria forming biofilms have been increasingly reported to be involved in systemic diseases. A close relationship between microbial infections and vascular disease has also been reported in the past two decades. The present review discusses the significance of the ecologic characteristics of biofilms formed by periodontopathic bacteria in order to further clarify the associations between periodontal disease and systemic disease. We focus on the relationships between periodontal disease-associated bacteria forming biofilms and vascular diseases including atherosclerosis and carotid coronary stenotic artery disease, and we discuss the direct and indirect effects on vascular diseases of lipopolysaccharides as well as heat shock proteins produced by periodontopathic bacteria.

Suppression of ARG kinase activity by STI571 induces cell cycle arrest through up-regulation of CDK inhibitor p18/INK4c

ARG is a tyrosine kinase closely related to ABL, which is oncogenic when fused to the transcriptional repressor ETV6 (ETS translocation variant 6). In this study, we investigated the growth-inhibitory effect of STI571 (signal transduction inhibitor number 571) on ETV6/ARG-expressing cells and its molecular mechanisms using HT93A, a cell line derived from a patient with AML-M3 carrying t(1;12). STI571 effectively suppressed overall tyrosyl phosphorylation of intracellular proteins including ETV6/ARG fusion protein, as well as the growth of HT93A cells with an IC(50) of 200 nM. The growth inhibition was primarily because of cell cycle arrest at G1 phase when cells were treated with 100 nM STI571 for 48 h, and apoptosis was induced after longer exposure (72 h) or by a higher dose (1000 nM). STI571 increased the amount of p18/INK4c after 2 h of culture, when the cell cycle pattern was not yet affected, but not that of other CDK inhibitors (CKI). p18/INK4c was more abundant in G1-enriched fractions than in S- and G2/M-enriched fractions of STI571-treated HT93A cells, suggesting that the upregulation of p18/INK4c expression correlates with the cell cycle arrest. Treatment of HT93A cells with antisense oligonucleotides against the Ink4c gene abrogated the growth inhibition by STI571. These results suggest that leukemogenesis by an aberrant ARG kinase involves the suppression of p18/INK4c, which is ubiquitously expressed and considered the major CKI in hematopoietic stem cells. STI571 can be an effective drug for the treatment of leukemias with deregulated ARG kinase activity.

PCR method is essential for detecting Mycobacterium tuberculosis in oral cavity samples

Tuberculosis is a re-emerging infectious disease, and infection by Mycobacterium tuberculosis has been increasing in immunocompromised hosts, including elderly persons. M. tuberculosis-infected persons may receive dental treatment. To evaluate the risk of M. tuberculosis infection in dental clinics, we examined the detection rates of M. tuberculosis in sample of mixed saliva, dental plaque, extracted teeth, caries lesions, and denture plaque by nested polymerase chain reaction (PCR). The detection rates by PCR in samples from mixed saliva, dental plaque, caries lesions and denture plaque obtained from tuberculosis patients were 98.0%, 92.0%, 89.0%, and 100%, respectively. The detection rates by the culture method were 17.3%, 2.0%, 0%, and 0%, respectively. M. tuberculosis also was detected from the nontuberculous mycobacteria-infected group. Strains of Actinomyces naeslundii, Porphyromonas gingivalis, and Fusobacterium nucleatum inhibited the growth of clinical strains of M. tuberculosis, but strains of Streptococcus mutans, Streptococcus sanguinis, and Actinobacillus actinomycetemcomitans did not. The present study concludes that the PCR method is essential for detecting M. tuberculosis in oral samples.

Trazodone hydrochloride attenuates thermal hyperalgesia in a chronic constriction injury rat model

BACKGROUND AND OBJECTIVE

Trazodone hydrochloride is used in the treatment of neuropathic pain. However, the analgesic effects of trazodone on neuropathic pain are controversial. The study was undertaken to determine the analgesic effect of trazodone on a chronic constriction injury model.

METHODS

We tested the effect of trazodone on thermal hyperalgesia due to a chronic constriction injury of the sciatic nerve in rats and examined the effects of lesions in the descending and ascending serotonergic system induced by 5,7-dihydroxytriptamine (5,7-DHT).

RESULTS

The analgesic effects of trazodone showed a clear dose dependency. Furthermore, the analgesic effect of trazodone was observed in rats injected with 5,7-DHT into the dorsal raphe nucleus and medial raphe nucleus.

CONCLUSIONS

The results suggest that a mainly serotonergic descending pain control pathway mediates the analgesic effects of trazodone.

Sonographic features of hepatic artery calcification in chronic renal failure

PURPOSE

Little is known about radiological aspects of hepatic artery calcification. For this reason, the sonographic features of calcified hepatic arteries were studied in patients with chronic renal failure who frequently develop tissue calcification due to hyperparathyroidism.

MATERIAL AND METHODS

Ultrasound was performed in 314 patients on dialysis who underwent examination of the liver, spleen and kidney twice in the past 4 years and were reevaluated with particular attention to acoustic shadowing. Abdominal CT was carried out in 219 of these 314 patients, and ultrasound findings were reevaluated with reference to CT findings.

RESULTS

A large acoustic shadow was seen in the hilum that corresponded to the calcified hepatic artery on CT in 8 patients, and in another 9, a similar large shadow was seen in the hilum without CT confirmation. Acoustic shadows of various sizes were definitely or most likely due to arterial calcification within the liver in 36 patients. The strength of shadow depended on the angle at which the ultrasound beam hit the artery. Probable calcification of small arteries accompanying portal veins was seen in 70 patients. These changes are different from those due to pneumobilia and biliary tract diseases.

CONCLUSION

Calcification of the hepatic artery can be identified by its acoustic shadow.

Sonographic features of hepatic artery calcification in chronic renal failure

PURPOSE

Little is known about radiological aspects of hepatic artery calcification. For this reason, the sonographic features of calcified hepatic arteries were studied in patients with chronic renal failure who frequently develop tissue calcification due to hyperparathyroidism.

MATERIAL AND METHODS

Ultrasound was performed in 314 patients on dialysis who underwent examination of the liver, spleen and kidney twice in the past 4 years and were reevaluated with particular attention to acoustic shadowing. Abdominal CT was carried out in 219 of these 314 patients, and ultrasound findings were reevaluated with reference to CT findings.

RESULTS

A large acoustic shadow was seen in the hilum that corresponded to the calcified hepatic artery on CT in 8 patients, and in another 9, a similar large shadow was seen in the hilum without CT confirmation. Acoustic shadows of various sizes were definitely or most likely due to arterial calcification within the liver in 36 patients. The strength of shadow depended on the angle at which the ultrasound beam hit the artery. Probable calcification of small arteries accompanying portal veins was seen in 70 patients. These changes are different from those due to pneumobilia and biliary tract diseases.

CONCLUSION

Calcification of the hepatic artery can be identified by its acoustic shadow.

Acute renal failure and hearing loss due to sodium bromate poisoning: a case report and review of the literature

Acute renal failure with hearing loss due to sodium bromate intoxication is described. A 48-year-old woman who ingested permanent wave neutralizer in a suicide attempt and developed anuria was admitted to our hospital for hemodialysis. Bromate intoxication was suspected and hemodialysis was carried out; she required maintenance dialysis 3 times a week. Irreversible severe sensorineural hearing loss continued and peripheral polyneuropathy developed in the lower limbs. We measured the concentration of bromine in the serum before and after the first hemodialysis and found its removal rate to be 61.3%. This is the first report that proved the utility of hemodialysis for bromate intoxication in a clinical setting.

Mycobacterium leprae and leprosy: a compendium

Leprosy is a chronic infectious disease caused by Mycobacterium leprae, which was discovered by G.H.A. Hansen in 1873. M. leprae is an exceptional bacterium because of its long generation time and no growth in artificial media. Entire sequencing of the bacterial genome revealed numerous pseudogenes (inactive reading frames with functional counterparts in M. tuberculosis) which might be responsible for the very limited metabolic activity of M. leprae. The clinical demonstration of the disease is determined by the quality of host immune response. Th1-type immune response helps to kill the bacteria, but hosts are encroached upon when Th2-type response is predominant. The bacteria have affinity to the peripheral nerves and are likely to cause neuropathy. M. leprae/laminin-alpha2 complexes bind to alpha/beta dystroglycan complexes expressed on the Schwann cell surface. WHO recommends a chemotherapy protocol [multidrug therapy (MDT)] which effectively controls the disease and contributes to the global elimination program. Leprosy has been stigmatized throughout history, and recent topics regarding the disease in Japan are also discussed.

Regulation of endometrial prostaglandin F(2alpha) synthesis during luteolysis and early pregnancy in cattle

Luteal regression is caused by a pulsatile release of prostaglandin (PG) F(2alpha) from the uterus in the late luteal phase in most mammals including cattle. Although it has been proposed in ruminants that pulsatile PGF(2alpha) secretion is generated by a positive feedback loop between luteal and/or hypophyseal oxytocin and uterine PGF(2alpha), the bovine endometrium may possess other mechanisms for initiation of luteolytic PGF(2alpha) secretion. It has been recently demonstrated that tumor necrosis factor-alpha (TNF-alpha) stimulates PGF(2alpha) output from bovine endometrial tissue not only during the follicular phase but also during the late luteal phase, suggesting that TNF-alpha is a factor in the initiation of luteolysis in cattle. Furthermore, our recent study has shown that IFN-tau suppresses the action of TNF-alpha on PGF(2alpha) synthesis by the bovine endometrium in vitro, suggesting that IFN-tau plays a luteoprotective role by inhibiting TNF-alpha-induced PGF(2alpha) production in early pregnancy. On the other hand, factors other than oxytocin or TNF-alpha have also been suggested to be involved in the regulation of PGF(2alpha) synthesis by bovine endometrium. The purpose of this review is to summarize our current understanding of the endocrine mechanisms that regulate the timing and pattern of uterine PGF(2alpha) secretion during the estrous cycle and early pregnancy.

Transformation of Ba/F3 cells and Rat-1 cells by ETV6/ARG

ETV6/ARG, a novel fusion gene composed of the ETV6 HLH oligomerization domain and most of sequences of the ARG protein tyrosine, was recently identified in human leukemia cells. The presence of the ETV6/ARG translocation raises the possibility that the resulting fusion protein functions as an oncogene. However, the transforming activity of the ETV6/ARG protein has not been determined and its contribution to leukemogenesis is therefore unknown. Here we address this question by analysing the oncogenic activity of ETV6/ARG in hematopoietic and fibroblast cells. It is demonstrated that expression of ETV6/ARG confers IL3-independent growth to Ba/F3 cells and anchorage independent growth to Rat-1 fibroblasts. It is also shown that multiple signaling molecules, including PI3K, SHC, ras-GAP and CRK-L, are tyrosine phosphorylated in Ba/F3 cells that express ETV6/ARG. Analysis of four different types of ETV6/ARG transcripts previously identified in the AML-M3 leukemia cell line HT93A suggest that ETV6 HLH domain is required for oncogenic activity. Based upon these results it is concluded that ARG can be activated as an oncogene in human malignancy and that the ETV6/ARG oncoprotein triggers some of the same signaling pathways associated with activated ABL oncogenes.

Functional morphology of adult female Culex quinquefasciatus midgut during blood digestion

The adult female Culex quinquefasciatus midgut comprises a narrow anterior and a dilated posterior region, with epithelia composed of a monolayer of adjacent epithelial cells joined at the apical portion by septate junctions. Densely packed apical microvilli and an intricate basal labyrinth characterise each cell pole. Our morphological studies suggest that, during blood digestion, the anterior midgut region also participates in an initial absorptive stage which is probably related to the intake of water, salts and other small molecules. This activity peaked by 6h after bloodmeal feeding (ABF) and ended approximately 18 h ABF, when the peritrophic membrane was already formed. After this time, absorption only occurred in the posterior region, with morphologic and biochemical evidence of high synthetic activity related to the secretion of proteases. Chymotrypsin, elastase, aminopeptidase, and trypsin reached their maximum activity at around 36 h ABF. Digestion products were apparently absorbed and transported to the basal labyrinth, from where they should be released to the hemolymph. At 72 h ABF, proteolysis had already ended and protein levels had returned to those observed before blood meal. The epithelium of the posterior region, however, did not return to its initial morphology, appearing quite disorganised. Additionally, from 48 h ABF onwards some epithelial cells showed morphological signals of apoptosis.

Immunomodulation by apoptosis-inducing caspases for an influenza DNA vaccine delivered by gene gun

Apoptosis-inducing caspases have been tested for immunomodulatory effect on a gene gun-delivered DNA vaccine which expresses influenza hemagglutinin. Attenuated murine caspase 2 and a chimera of murine caspase 2 prodomain and human caspase 3 strongly enhanced humoral and cell-mediated immune response to hemagglutinin when they were co-administered with an immunogen DNA. In contrast, wild-type caspases did not enhance the DNA-raised immune response. Caspase dose-dependent antibody response curve revealed that the antibody level was in inverse relation to the amount of administered caspase. These findings indicate that bland apoptosis of antigen-harboring cells can elicit enhanced immune responses. Extensive apoptosis interferes with the generation of immune response. Gene gun delivery involving caspases elicited type-2 immune responses that characterized with dominant IL-4 and IgG1 production. ELISPOT assays showed that CD4 T cells were preferentially activated, while CD8 T cell response remained at marginal level. Using attenuated caspases for gene gun DNA vaccination is a useful approach to amplify type-2 immune responses.

Tumour necrosis factor-alpha receptors are present in the corpus luteum throughout the oestrous cycle and during the early gestation period in pigs

To determine the physiological significance of tumour necrosis factor-alpha (TNFalpha) in the regulation of luteal functions in pig, this study was conducted to identify the presence of functional TNFalpha receptors in porcine corpora lutea (CL) throughout the oestrous cycle and the early gestation. The CL were isolated from pigs on days 4, 6, 8, 12 or 15 of the oestrous cycle (n=3; day 0 = oestrus) and days 15, 20 or 25 of gestation (n=3; day 0 = mating). A Scatchard analysis revealed the presence of a high-affinity binding site for TNFalpha in all samples (dissociation constant; 2.7 +/- 0.51 to 5.8 +/- 0.50 nM). The concentration of TNFalpha receptors was higher on day 15 of the oestrous cycle than on days 4 and 8 of the oestrous cycle (p < 0.05). Furthermore, TNFalpha receptor concentrations in the CL on days 15, 20 and 25 of gestation were significantly lower than on day 15 of the oestrous cycle (p < 0.05). On day 9 of the oestrous cycle, exposure of cultured luteal cells to 0.06-60 nM TNFalpha stimulated prostaglandin (PG) F2alpha and PGE2 secretion in a dose-dependent manner (p < 0.05). These results indicate that functional TNFalpha receptors are present in the porcine CL throughout the oestrous cycle and early gestation, and suggest that TNFalpha plays one or more physiological roles in regulating CL function throughout the oestrous cycle and the early gestation period. In addition, TNFalpha receptor concentration in the CL of the late luteal stage (day 15) of the oestrous cycle was higher than on the respective day in the early pregnant pig, suggesting that TNFalpha plays a role in accomplishing luteolysis in the porcine CL.

Correlation between the bronchial subepithelial layer and whole airway wall thickness in patients with asthma

BACKGROUND

The epithelial reticular basement membrane (Rbm) of the airway wall thickens in patients with asthma. However, whether the thickening parallels whole airway wall thickening, which limits airflow, is unknown. The aim of this study was to examine the correlation between the bronchial Rbm thickening and whole airway wall thickening in asthma. In addition, the association of Rbm and whole wall thickening with airflow obstruction was examined.

METHODS

Forty nine patients with asthma and 18 healthy control subjects took part in the study. The Rbm thickness was measured in bronchial biopsy specimens and whole airway wall thickness was assessed with high resolution computed tomographic (HRCT) scanning after pretreatment with oral steroids for 2 weeks and inhaled beta2 agonist to minimise reversible changes of the airway walls. The percentage airway wall area (WA%; defined as (wall area/total airway area) x 100) and percentage airway wall thickness (WT%; defined as [(ideal outer diameter - ideal luminal diameter)/ideal outer diameter] x 100) were determined from HRCT scans to assess whole airway wall thickness. Spirometric tests were also performed.

RESULTS

WA% and WT% were higher in patients with asthma than in healthy subjects. Both WA% and WT% were strongly correlated with Rbm thickness. Moreover, these three indices of airway wall thickness were inversely correlated with the percentage of predicted forced expiratory volume in 1 second in patients with asthma.

CONCLUSIONS

These findings indicate that Rbm thickening parallels whole airway wall thickening which can cause irreversible airflow obstruction in patients with asthma.

[Chemotherapy for small-cell lung cancer (SCLC) patients with renal failure]

We administered chemotherapy in three cases of small-cell lung cancer (SCLC) with renal failure under different situations. Hemodialysis (HD) was used in 2 out of the 3 cases. Case 1 was complicated by acute renal failure from extensive bilateral tumor invasion. After chemotherapy (CBDCA + ETP) under HD, renal metastases regressed and renal function improved, although the final response was PD. In case 2, HD had been introduced for diabetic nephropathy. After 2 cycles of chemotherapy (CBDCA + ETP) under HD, the patient attained a PR. Case 3 is an example of paraneoplastic nephrotic syndrome with renal failure. Chemotherapy including CBDCA or CDDP was performed and the QOL of the patient improved. Pro-GRP and serum creatinine changed in parallel during the clinical course of 6 admissions. In conclusion, individualized therapy is necessary to increase survival time of SCLC patients with renal failure. Although chemotherapy is useful, further study is needed for the selection of suitable chemotherapeutic regimens, optimal dosage of each drug and the timing of HD.

Iron-Mediated regulation of alkaline proteinase production in Pseudomonas aeruginosa

We analyzed the regulation by iron of alkaline proteinase (AP) production in Pseudomonas aeruginosa. Extracellular AP production was detected from the mid-logarithmic to the stationary phase by an antibody-based assay system, and was strongly repressed by iron in the medium. This repression was shown by Northern hybridization and primer extension to occur at the level of transcription. The primer extension analysis revealed that the start point of transcription of AP gene was the nucleotide position -84 from the start point of translation. Furthermore, we investigated whether this transcriptional repression involved PvdS protein. Using the mutant strain of pvdS, the alternative sigma factor gene revealed that the PvdS protein is required for the full expression of AP, and a previous study showed that expression of pvdS is also repressed by iron. Therefore, we thought that one mechanism of repression of AP production operated through reduction of the PvdS protein level. Purified AP decomposed the transferrin, and released iron from it. Purified AP added to the medium containing transferrin as the only iron source enhanced the growth of P. aeruginosa. Moreover, mutation in the AP gene decreased the growth rate in the medium containing the transferrin as the only iron source. These results clearly indicated that AP expression should occur in a free-iron-deficient environment and emphasized the importance of AP to iron acquisition in the infection site.

Ground-glass hepatocytes in fibrinogen storage disease in Japanese Black calves

This paper reports the occurrence of large intracytoplasmic inclusions observed in the hepatocytes of six Japanese Black calves showing clinical illness. These inclusions were round to elongated polyhedral in shape, with a consistently homogeneous glassy appearance. Hepatocytes with the inclusions had a ground-glass appearance. The inclusions were negative for the periodic acid-Schiff reaction and methenamine silver stain. Immunohistochemically, they were strongly positive for fibrinogen. Electron microscopy revealed that the inclusions consisted of granular material, showing moderate electron density and bounded by a unit membrane. On the external surface of the unit membrane, there were direct connections to cellular organelles, including the ribosomes and rough-surfaced endoplasmic reticulum. The results showed these inclusions to be entirely consistent with fibrinogen inclusions described in man. Hepatocellular fibrinogen storage disease, as identified in this study, has not previously been described in animals.

A case of hepatocellular carcinoma rupturing after angiography

We report a case of primary hepatocellular carcinoma (referred to as hepatocellular carcinoma below) apparently rupturing after angiography. The patient was a 62-year-old male who was admitted for the treatment of hepatocellular carcinoma. Ultrasonography (US) and computed tomography (CT) on admission showed a tumor occupying the entire left lobe of the liver and partly protruding outside the liver and a tumor embolus in the portal vein. We performed preoperative angiography, after which fever and abdominal discomfort appeared. Two days after the angiography, abdominal pain and a rapid increase in the size of the abdominal tumor were noted. US also revealed an unquestionable increase in the size of the tumor, leading to a diagnosis of intratumoral hemorrhage due to the rupture of hepatocellular carcinoma. Since child classification A, clinical stage I and ICG 11.7% indicated an adequate functional reserve of the liver, we performed an emergency operation. Laparotomy revealed that the tumor occupied almost the entire left lobe of the liver, partly protruded outside it, and was bleeding from part of its anterior surface. The volume of intra-abdominal hemorrhage was about 100 ml. A portal tumor embolus was present in the portal vein from the horizontal part to the trunk. We performed resection of the left and caudate lobes of the liver with removal of the portal tumor embolus. The resected specimens showed a hemorrhage in and around the tumor. We speculated that in a hepatocellular carcinoma that involves the surface of the liver and is complicated by tumor embolism of the portal vein, angiography could trigger the rupture of the carcinoma.