Tripartite motif-containing 9 promoted proliferation and migration of bladder cancer cells through CEACAM6-Smad2/3 axis

Studies have shown that tripartite motif-containing (TRIM) family proteins function as E3 ubiquitin ligases and play essential roles in cancer biology. In the present study, we validated a contribution of TRIM9 to bladder cancer progression. 296 patients derived from The Cancer Genome Atlas (TCGA) database and 22 clinical specimens were included, in which accumulated TRIM9 correlated with the poor prognosis and higher relapse in bladder patients. In vitro, TRIM9 promoted bladder cancer cells Biu-87 and T24 cell proliferation and migration. Meanwhile, overexpression of TRIM9 reduced the chemosensitivity in Biu-87 and T24 to mitomycin C (MMC) and gemcitabine (GEM). As an underlying mechanism, we found that TRIM9 stimulated carcinoembryonic antigen 6 (CEACAM6) upregulation, which further facilitated Smad2/3-matrix metalloproteinase 2 (MMP2) signaling activation both in vitro and in vivo. Those results indicated that TRIM9 facilitated bladder cancer development and chemoresistance by CEACAM6-Smad2/3 axis. TRIM9 and its associated molecules could be a potential diagnostic indicator and therapeutic target in bladder cancer.

Measurement of the ^{18}O(α, γ)^{22}Ne Reaction Rate at JUNA and Its Impact on Probing the Origin of SiC Grains

The ^{18}O(α,γ)^{22}Ne reaction is critical for AGB star nucleosynthesis due to its connection to the abundances of several key isotopes, such as ^{21}Ne and ^{22}Ne. However, the ambiguous resonance energy and spin-parity of the dominant 470 keV resonance leads to substantial uncertainty in the ^{18}O(α,γ)^{22}Ne reaction rate for the temperature of interest. We have measured the resonance energies and strengths of the low-energy resonances in ^{18}O(α,γ)^{22}Ne at the Jinping Underground Nuclear Astrophysics experimental facility (JUNA) with improved precision. The key 470 keV resonance energy has been measured to be E_{α}=474.0±1.1  keV, with such high precision achieved for the first time. The spin-parity of this resonance state is determined to be 1^{-}, removing discrepancies in the resonance strengths in earlier studies. The results significantly improve the precision of the ^{18}O(α,γ)^{22}Ne reaction rates by up to about 10 times compared with the previous data at typical AGB temperatures of 0.1-0.3 GK. We demonstrate that such improvement leads to precise ^{21}Ne abundance predictions, with an impact on probing the origin of meteoritic stardust SiC grains from AGB stars.

[Whole transcriptome analysis and critical gene regulatory network analysis during Schistosoma japonicum infection and praziquantel treatment in mice]

OBJECTIVE

To investigate long non-coding RNA (lncRNA)-microRNA (miRNA)-messenger RNA (mRNA) interactions and identify the critical gene regulatory network during Schistosoma japonicum infections and praziquantel treatment using whole transcriptome sequencing.

METHODS

A total of 110 male C57BL/6 mice were randomly divided into the control group, the infection group and the treatment group. Mice in the infection treatment and the control group were infected with S. japonicum cercariae via the abdomen, and liver specimens were sampled from 10 mice 3, 6, 8 weeks post-infection. Praziquantel treatment was given to mice in the treatment group 8 weeks post-infection, and liver specimens were sampled from 10 mice 2, 4, 6, 8, 10 weeks post-treatment. Total RNA was isolated from mouse liver specimens, and the transcriptome library was constructed for highthroughput whole transcriptome sequencing. The significant differentially expressed genes were subjected to functional annotations, Gene Ontology (GO) terms enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. Correlation analysis of liver specimens was performed using R Corrplot and Himsc functions, and the lncRNAmiRNA-mRNA interaction network analysis was performed using R MixOmics and Himsc functions.

RESULTS

There were 1 176 differentially expressed miRNAs, 5 270 differentially expressed mRNAs, and 2 682 differentially expressed lncRNAs between the infection group and the control group, 1 289 differentially expressed miRNAs, 7 differentially expressed mRNAs, and 69 differentially expressed lncRNAs between the treatment group and the infection group, and 1 210 differentially expressed miRNAs, 4 456 differentially expressed mRNAs, and 2 016 differentially expressed lncRNAs between the treatment group and the control group. Correlation analysis showed a higher correlation of gene expression between the treatment group and the control group. Principal component analysis showed obvious separate clustering between the infection group and the treatment group. The differentially expressed genes with significant relevance were significantly enriched in 24 GO terms, including arachidonic acid metabolic process, xenobiotic catabolic process, unsaturated fatty acid metabolic process, xenobiotic metabolic process, long-chain fatty acid metabolic process, and 8 KEGG metabolic pathways, including cholesterol metabolism, tyrosine metabolism, linoleic acid metabolism, retinol metabolism, and steroid hormone biometabolism.

CONCLUSIONS

There were 23 mRNAs including Cyp2b9 and 14 lncRNAs including Rmrpr in the core position of the gene regulatory network, which may play a critical role in S. japonicum infections and praziquantel treatment, and 9 miRNAs including miR-8105 may serve as potential molecular markers for diagnosis of S. japonicum infections.

[A prospective cohort study on BMI levels and risk of acute pancreatitis]

Objective: To investigate the effects of body mass index (BMI) levels at different baseline on the risk of new-onset acute pancreatitis (AP). Methods: The subjects were from the Kailuan Study Cohort and divided into 3 groups according to baseline BMI levels: BMI<24 kg/m², normal weight; BMI 24-28 kg/m², overweight; BMI≥28 kg/m², obesity. The incidence of new-onset AP in these three groups was analyzed. The survival curve was plotted by Kaplan-Meier method, the cumulative incidence was calculated and tested by log-rank method. Multivariate Cox proportional hazards regression model was used to calculate HR of baseline BMI levels for AP. Results: A total of 123 841 subjects were included and followed up for (11.94±2.13) years, during which, 395 cases were found with AP. The incidence of AP was 2.67 per 10 000 person years in total population, and the incidences of AP were 2.20, 2.72 and 3.58 per 10 000 person-years in the normal, overweight and obesity groups, respectively. The cumulative incidences of AP was 0.32%, 0.40% and 0.49% in normal, overweight and obesity groups, respectively, which showed a significant inter-group difference by log-rank test (χ ²=13.17,P<0.01). The results of multivariable adjusted Cox proportional hazards regression model analysis indicated that obesity group (HR=1.45, 95%CI: 1.10-1.92) had a higher risk for AP compared with the normal BMI group. The subgroup analyses by age and sex showed that compared with the normal weight group,the HRs for AP in the obesity group was 1.58(95%CI:1.14-2.19) and 1.40(95%CI:1.03-1.90) among subjects younger than 60 years old and male subjects, respectively. After excluded onset AP within two years from baseline,with a control group from normal weight,the results of multivariate Cox proportional hazards regression model analysis indicated that the AP in the obesity group was 1.60 (95%CI: 1.18-2.15). Conclusion: Obesity may increase the risk of developing AP, particularly among young and middle-aged men.

Direct Measurement of the Astrophysical ^{19}F(p,αγ)^{16}O Reaction in the Deepest Operational Underground Laboratory

Fluorine is one of the most interesting elements in nuclear astrophysics, where the ^{19}F(p,α)^{16}O reaction is of crucial importance for Galactic ^{19}F abundances and CNO cycle loss in first generation Population III stars. As a day-one campaign at the Jinping Underground Nuclear Astrophysics experimental facility, we report direct measurements of the essential ^{19}F(p,αγ)^{16}O reaction channel. The γ-ray yields were measured over E_{c.m.}=72.4-344  keV, covering the Gamow window; our energy of 72.4 keV is unprecedentedly low, reported here for the first time. The experiment was performed under the extremely low cosmic-ray-induced background environment of the China JinPing Underground Laboratory, one of the deepest underground laboratories in the world. The present low-energy S factors deviate significantly from previous theoretical predictions, and the uncertainties are significantly reduced. The thermonuclear ^{19}F(p,αγ)^{16}O reaction rate has been determined directly at the relevant astrophysical energies.

Expression of apolipoprotein C1 in clear cell renal cell carcinoma: An oncogenic gene and a prognostic marker

This study aimed to explore whether APOC1 expression has a function in the biological behavior of clear cell renal cell carcinoma (ccRCC) cells and its possible mechanism. Bioinformatics analysis of data TCGA and OnComine was conducted to explore the expression pattern and prognostic value of APOC1, as well as the relationship between APOC1 expression and clinical indicators. Loss- and gain- of APOC1 function assays were carried out to assess the biological functions of APOC1. Western blotting was applied to detect protein expression. We revealed that APOC1 was upregulated in ccRCC tissues. APOC1 expression was related to gender, grade, pathologic-T, pathologic-stage, and pathologic-M in patients with ccRCC. Meanwhile, Kaplan-Meier analysis evidenced that the high APOC1 expression indicated unfavorable outcomes of ccRCC. Functional experiments in vitro revealed that upregulation of APOC1 in UT33A cells promoted cell proliferation, invasion, and migration, while downregulation of APOC1 in 786-O cells had the opposite effect. Furthermore, epithelial mesenchymal transition (EMT) was activated in cells with upregulated APOC1 but inhibited in cells with down-regulated APOC1. Collectively, our data suggested that APOC1 was overexpressed in ccRCC cells and promoted the malignant biological behaviors and EMT of ccRCC cells.

Scrotal elephantiasis associated with follicular occlusion triad: A case report and literature review

RATIONALE

Follicular occlusion triad (FOT) is an autosomal recessive inherited disease and no more than 3 variants of the triad have been reported. We give a report in which scrotal elephantiasis is a variant of FOT and further perform a literature review.

PATIENT CONCERNS

A 41-year-old man came to us because of a large scrotal cyst and generalized skin lesions that had occurred over the past 10 years. The generalized skin lesions consisted of hidradenitis suppurativa on the perineum and back, acne conglobata in the armpit, and dissecting cellulitis of the scalp. He took antibiotics for a long time but achieved poor effect. Furthermore, he told his father and elder brother also manifested such skin lesions.

DIAGNOSES

Magnetic resonance showed a mass in the left scrotum with clear boundaries. A routine blood test showed a high leukocyte level of 12 × 10/L and a hemoglobin content of 78 g/L. C-reactive-protein increased. Series of autoimmune antibody tests were negative. The postoperative pathologic findings showed that the mass was an epidermoid cyst, and hematoxylin and eosin staining showed hyperkeratosis of the skin as well as inflammatory and edematous changes. A diagnosis of a variant of FOT was made.

INTERVENTIONS

We removed skin abscesses and lesioned the inner part with hydrogen peroxide. Then we performed an excision of the scrotal lesion.

OUTCOME

The patient recovered well and had no evidence of recurrence at a 16-month follow-up.

LESSONS

We reported a case in which scrotal elephantiasis was a variant of FOT and surgical intervention played an important role in secondary urologic diseases.

Polyphasic taxonomy of Aspergillus section Cervini

Species belonging to Aspergillus section Cervini are characterised by radiate or short columnar, fawn coloured, uniseriate conidial heads. The morphology of the taxa in this section is very similar and isolates assigned to these species are frequently misidentified. In this study, a polyphasic approach was applied using morphological characters, extrolite data, temperature profiles and partial BenA, CaM and RPB2 sequences to examine the relationships within this section. Based on this taxonomic approach the section Cervini is resolved in ten species including six new species: A. acidohumus, A. christenseniae, A. novoguineensis, A. subnutans, A. transcarpathicus and A. wisconsinensis. A dichotomous key for the identification is provided.

The applicability of Ki-67 marker for renal epithelioid angiomyolipoma: experience of ten cases from a single center

In order to present our experience with 10 cases of renal epithelioid angiomyolipoma (EAML) and validate the applicability of Ki-67 (proliferation marker) for EAML, we reviewed medical records of 10 consecutive cases diagnosed EAML from January 2005 to February 2012 at our department. Clinical data were collected and analyzed and pathology slides were reviewed. The immunohistochemical reactions for Ki-67 were performed and tumors showed positive expression were estimated. Active follow-up was performed to investigate the association between Ki-67 expression and the prognosis. The mean age and tumor size of the patients was 43.6 years (range 32-56) and 8.2 cm (range 2-15 cm), respectively. Seven were females while three were males. Radical nephrectomy was performed in 6 patients, partial nephrectomy in 3, and renal artery ligation in 1. The immunohistochemical reactions for HMB-45 (Human Melanoma Black), SMA (Smooth Muscle Actin) were positive but for S-100 were negative. The number of patients showing positive/negative Ki-67 expression was 5/5. The survival rate of the positive group was 20% (1/5) while 100% (5/5) of the negative group during the median follow-up time of 26.75 months (range 1-53). Recurrence, metastasis and death due to disease occurred in 1 (10%), 3 (30%) and 4 (40%) patients, respectively. Higher expression (positive) of Ki-67 indicates the presence of EAML and poor prognosis of patients. Surgical excision including radical and partial nephrectomy is a considerable approach to the treatment for its malignant potential.

Comparison of a paraspinal approach with a percutaneous approach in the treatment of thoracolumbar burst fractures with posterior ligamentous complex injury: a prospective randomized controlled trial

OBJECTIVE

This prospective randomized controlled study compared the efficacy and safety of two paraspinal muscle-sparing surgical approaches for the management of neurologically intact patients with thoracolumbar burst fractures and posterior ligamentous complex injuries.

METHODS

Patients were randomized to undergo either percutaneous (n=31) or paraspinal (n=30) fluoroscopically-guided pedicle screw-rod fixation, and were followed for ≥3 years. Preoperative postural reduction was attempted in all patients.

RESULTS

The percutaneous approach was associated with significantly less intraoperative blood loss and shorter duration of surgery and hospitalization, as well as less pain and better functional recovery at 3 months after surgery compared with the paraspinal approach. Paraspinal surgery resulted in significantly better correction of kyphosis and restoration of vertebral height compared with percutaneous surgery. There were no differences in long-term clinical outcomes between the two groups.

CONCLUSIONS

The minimally invasive percutaneous approach appears to be better in cases of successful postural reduction. The paraspinal approach results in better surgical correction and is, therefore, recommended for patients without successful postural reduction.

Influence of clinical characteristics and tumor size on symptoms of bladder leiomyoma: a pooled analysis of 61 cases

BACKGROUND

Bladder leiomyoma is an uncommon type of bladder neoplasms. Most publications are reports of isolated cases. The influence of tumor size on patients' early symptoms was seldom analyzed. We aim to investigate the clinical characteristics of bladder leiomyoma and the influence of tumor size on patients'symptoms in Chinese population.

METHODS

We reviewed the medical records of eight patients diagnosed with bladder leiomyoma at our department, collected 53 cases from Chinese National Knowledge Infrastructure (CNKI), Wangfang data base, and Chinese Biological Medicine Disk, and performed a pooled analysis. The clinical characteristics of the patients were analyzed and then classified into symptomatic and asymptomatic groups. The association between tumor size and the occurrence of symptoms was evaluated. Furthermore, Logistic regression model was constructed to discriminate variables.

RESULTS

Women comprised the majority of the patients (49/61, 80.3%). The mean age and tumor size were (42.3 ± 14.0) years and (45.0 ± 25.7) mm, respectively. Among all the symptoms, irritative symptoms occurred most frequently (37.7%, 23/61), followed by obstructive urinary symptoms (31.1%, 19/61), hematuria (24.6%, 15/61), and abdominal bulge or pain (14.8%, 9/61). In our study, patients who were 45 years old or younger tended to be asymptomatic compared with elder ones (14/36 vs. 3/25, P = 0.021). The histological, as well as anatomical, location of tumor, did not show significant differences between symptomatic and asymptomatic patients (P = 0.306 and 0.700). Tumors larger than 30 mm in the greatest diameter would cause clinical symptoms such as obstructive urinary symptoms (P = 0.048) and irritative symptoms (P = 0.037). Logistic regression confirmed the association between tumor size and the occurrence of symptoms, which was related with age.

CONCLUSIONS

Bladder leiomyoma occurs mainly in women and most frequently with irritative symptoms. The occurrence of symptoms is related to tumor size rather than the location. In this setting, patients with endovesical tumors smaller than 30 mm in the greatest diameter tended to be asymptomatic, which were usually treated with transurethral resection of bladder tumor.

Anti-IgM-induced down-regulation of nuclear Thy28 protein expression in Ramos B lymphoma cells

We recently cloned mouse Thy28 cDNA (mThy28), which is highly conserved among vertebrates and plants. The mThy28 mRNA is highly expressed in testis, liver, kidney, brain, with moderate expression in thymus, spleen, and heart. In the present study, characteristics of mouse Thy28 protein expression were examined using rabbit anti-mThy28 polyclonal antibody (Ab). Levels of mThy28 protein expression were highest in testis, with moderate expression in liver, spleen, and thymus. The Thy28 protein was mainly located in the nucleus, which was revealed by immunofluorescence microscopy and Western blotting using anti-mThy28 Ab, and transient expression of the mThy28/EGFP fusion gene. Engagement of membrane immunoglobulin with anti-IgM induced down-regulation of human Thy28 expression at both mRNA and protein levels, accompanied by induction of apoptosis in Ramos B lymphoma cells. Expression of protein and mRNA and induction of apoptosis were evaluated by flow cytometry/Western blotting, reverse transcription-polymerase chain reaction, and propidium iodide staining, respectively. Anti-IgM also down-regulated the promoter activity of the mThy28 gene, as demonstrated by luciferase assay. Thus, the anti-IgM-induced down-regulation of the nuclear Thy28 expression appears to correlate with the induction of apoptosis in Ramos B lymphoma cells.

[Observation of plasma levels of beta-endorphin in patients with trigeminal neuralgia]

OBJECTIVE

To observe the relationship between plasma levels of beta-endorphin and trigeminal neuralgia.

METHODS

During the attacks of trigeminal neuralgia, beta-endorphin levels of plasma from external jugular, cubital fossa vein blood ipsilateral to the pain and contralateral external jugular vein blood were assessed by sensitive radioimmunoassay in 12 cases, after operations the venous blood from the ipsilateral external jugular vein was sampled again, the external jugular vein blood of 12 normal volunteers was collected as control.

RESULTS

The plasma levels of beta-endorphin in patients with trigeminal neuralgia were significantly lower than that in normal volunteers (P<0.05).

CONCLUSION

The lowered plasma beta-endorphin levels may be an important factor for the development of pain in patients with trigeminal neuralgia, which may result in pain and neurogenic inflammation that can not be controlled in central nervous system and peripheral nerve terminals.

Long-term results of wide-field brachytherapy as the sole method of radiation therapy after segmental mastectomy for T(is,1,2) breast cancer

BACKGROUND

We hypothesized that wide-field brachytherapy (BRT) after margin negative excision would result in complication rates, local recurrence rates, and cosmesis scores equivalent to external beam radiotherapy (ERT).

METHODS

Patients with T(is,1,2) tumors less than or equal to 4 cm, 0 to 3 positive axillary nodes, and negative inked surgical margins were entered prospectively into BRT phase I/II trial. Patients who met the eligibility criteria for BRT but were treated with ERT during the same time period were retrospectively identified as controls. A blinded panel of healthcare professionals graded cosmetic outcome.

RESULTS

Fifty patients with 51 breast cancers received BRT from January 1992 to October 1993. We identified 94 patients eligible for BRT but concurrently treated with ERT. At a median follow-up of 75 months, the two groups were similar for grade III treatment toxicities, local/regional recurrence rates, and cosmesis scores.

CONCLUSIONS

For selected breast cancer patients undergoing breast-conserving therapy, BRT is an attractive alternative to ERT.

The effects of 2-bromopropane on viability and testosterone production ability of rat Leydig cells in primary culture

Epidemiological surveys and animal experiments have shown that 2-bromopropane induces oligozoospermia in exposed workers and inhibits spermatogensis in laboratory animals. However, the mechanism by which 2-bromopropane exerts its effects is unknown. To this end, we examined the formation of testosterone by the Leydig cells and their survival of these cells in the presence of different concentrations of 2-bromopropane in vitro. Leydig cells were isolated following vascular perfusion, enzymatic dissociation and Percoll gradient centrifugation techniques. The cells were cultured in culture dishes. After 8 h, different cultures were exposed to 2-bromopropane at concentrations of 0.01 mmol/L, 0.10 mmol/L and 1.00 mmol/L. In order to stimulate Leydig cells to secrete testosterone, human chorionic gonadotropin (hCG) was also added. Cell viability was determined using the trypan blue dye exclusion test and cell numbers were counted by hemocytometer. Testosterone secretion was detected by radioimmunoassay. The cell viability decreased after exposure to 2-bromopropane in a dose-dependent way, but no morphological change was observed. The cell number decreased in the 2-bromopropane-treated cultures. The secretion of testosterone did not manifest defectable changes in the culture treated with 0.10 mmol/L and 0.01 mmol/L of 2-bromopropane; however, it decreased significantly (P < 0.02) in the presence of 1.00 mmol/L. Therefore, our results strongly suggest that 2-bromopropane may exert its cytotoxic effects on Leydig cells in vitro. We speculate that the decrease in the numbers of Leydig cells caused by 2-bromopropane was mediated by a feedback mechanism resulting from a lower testosterone concentration.

[Clinical application study of intraoral high-level mandibular neurotomy: Reported of 19 cases]

Trigeminal neuralgia is a common disease in clinical practice. The recurrence rate after avulsion is relatively high. In order to reduce the recurrence rate, the author developed a new method and operated on 19 cases with intraoral high level trigeminal neurotomy based on 21 cases of adult human skull anatomy. The method is simple, safe and in good condition. The author emphasized that the proper management of the buccal branch during operation may have a close relation with the post-operative recurrence rate.

The distribution of HgCl2 in rat body and its effects on fetus

Both female and male Wistar rats were dividend into 3 groups according to their body weights. The two test groups were given 75 micrograms/ml and 7.5 micrograms/ml HgCl, respectively, via drinking water, while the control group was given distilled water. Animals were mated after the male rats were treated for 12 weeks and female rats for 2 weeks. Blood samples from rats were taken on the 18th day of the pregnancy and the results showed that the HgCl2 was absorbed and stored in the blood in the form of inorganic mercury. The greatest amount of HgCl2 was found in the kidney. The placenta and the tests also had high mercury deposits. Fetuses showed low levels of HgCl2, thus, the placenta appears to serve as a barrier against HgCl2. No pathological changes were observed in the placenta, ovary, liver, and kidney in the female rats, but the epithelial cells of the rental proximal convoluted tubules were cloudy and swelling. The renal corpuscle showed no changes in the male rats. Pathological examination showed that a portion of the seminiferous epithelia were falling off, and the number of sperm released by the male was reduced. Examination by electron microscopy revealed that particulate fat was increased in sperm cells, which suggests that spermatozoa had been degenerated and were possibly one of the causes for the decreased rates of pregnancy in the exposed groups. No malformation of organs and bones in the rat fetuses were observed.

[Three-dimensional computed tomography in the diagnosis of diseases of jaw bone(report of 22 cases).]

3DCT reconstruction,as a new roentnogenographic technique,has not been yet used so much in Oral Maxillofacial Surgery in our country.Scine early 1993,22 cases of 3DCT reconstruction have been performed on a Siemens Plus-s CT scanner for the diagnosis and surgical planning of jaw bone disease and injuries.It demonstrated that 3DCT reconstruction is a useful technique for the diagnosis and surgical planning of jaw bone disease.

Studies on the toxicity and maximum allowable concentration of chloroform

Chloroform has obvious hepato-, nephro-toxicity and carcinogenicity. In order to get necessary data for recommendation of maximum allowable concentration of chloroform in workplace, a series of studies were carried out. The results showed that exposed workers mainly distributed in the industries of perspex processing, production of refrigerants, drugs and pesticides. The exposure level ranged 4.27-147.91 mg/m3 in 119 air samples collected from 3 representative worksites, with 45.4% air samples below 20 mg/m3. The workers exposed to chloroform at 29.51 mg/m3 had slight liver damage indicated by the higher rates of abnormal serum prealbumin and transferrin levels than those of control workers. The neurobehavioral functions of these workers were also obviously affected, manifested as increases in scores of passive mood states and dose-related negative changes in neurobehavioral testing. The observed effect threshold concentration of subacute inhalation in rats was 592 mg/m3 according to the observation on the biochemical changes in liver tissue and abnormal activities of serum enzymes. Mainly based on the above results, we recommended 20 mg/m3 as the Maximum Allowable Concentration in workplace in China at present.

[The diagnosis and the treatment on lingual thyroid]

Lingual thyroid is a rare example of ectopic thyroid.This paper reported three cases of lingual thyroid(all female,aged between 16 and 61 years) were discussed with diagnosis and treatment.A transoral excision using the median total glossotomy and precervical excision was performed through a transsuprahyoid approach.Postoperative complications is not developed.The approach above mention is better than that of median labiomandibular glossotomy.

More precise localization of nasal tumors associated with chronic exposure of F-344 rats to formaldehyde gas

Considerable interest and research have resulted from the finding that squamous cell carcinomas, polypoid adenomas, and a small number of other nasal neoplasms occurred in F-344 rats following chronic inhalation exposure to formaldehyde. These tumors were reported to originate in the anterior portion of the nasal cavity but their precise location in the nose was not determined. Histologic sections from the nasal passages of these rats have been reexamined and the location of each tumor has been recorded. The majority of squamous cell carcinomas occurred on the anterior portion of the lateral aspect of the nasoturbinate and adjacent lateral wall (57%) or the midventral nasal septum (26%). Polypoid adenomas were confined to a small region of the anterior nasal cavity and were restricted to the free margins of the naso-and maxilloturbinates and lateral wall adjacent to these margins. One neoplasm, considered to be the malignant counterpart of the polypoid adenoma, originated on the dorsal margin of the maxilloturbinate in the same region of the nose. Remaining neoplasms were generally too large or too poorly preserved for assessment of their site of origin. Mechanistic studies directed toward a better understanding of the nasal carcinogenicity of formaldehyde, or other nasal carcinogens. should take into account the anatomic sites of origin of the neoplasms whenever this can be determined.

The nasal mucociliary apparatus. Correlation of structure and function in the rat

Rats are used extensively in inhalation toxicologic studies, but little information is available on the rat nasal mucociliary apparatus. The function of the rat nasal mucociliary apparatus was studied in vitro by video analysis, and its structure was examined by light and electron microscopy. Video analysis permitted determination of mucus flow rate and ciliary beat frequency without disrupting mucociliary function. In different regions of the nose, there was a characteristic mucus flow rate, flow pattern, and ciliary beat frequency, with minimal interanimal variation. Analysis of data pairs revealed no evidence of a correlation between mucus flow rate and ciliary beat frequency, ciliary length, density of the ciliated cell population, or the products of these factors. Mucus was seen to flow over certain nonciliated areas, and it is proposed that the mucus is pulled over these areas. Mucus flow characteristics indicated that the hypophase was less viscous than, and moved in the same direction as, the epiphase. The nasal mucus was present as a continuous layer over the respiratory epithelium, and had an osmiophilic surface film, which was found to be made up of 2 separate membranous components. On the basis of these studies, it was concluded that the rat nasal mucociliary apparatus represents a useful and readily accessible model for in vitro studies of nasal mucociliary function.

Respiratory tract lesions induced by sensory irritants at the RD50 concentration

Exposure of mice to airborne sensory irritants causes a concentration-dependent depression of respiratory rate. The RD50 concentration (that concentration which elicits a respiratory rate decrease of 50%) has been predicted to be an unacceptable occupational exposure concentration due to intolerable sensory irritation and possible respiratory tract injury in humans. The purpose of this study was (1) to determine whether lesions occur in the respiratory tract of Swiss-Webster mice after exposure to the RD50 concentrations of ten sensory irritants and (2) to compare these changes with respect to type and severity. The RD50 values (ppm) of the chemicals studied are as follows: 2,4-toluene diisocyanate (0.4), acrolein (1.7), formaldehyde (3.1), chloropicrin (8.0), chlorine (9.3), sulfur dioxide (117), ammonia (303), hydrogen chloride (309), dimethylamine (511), and epichlorohydrin (687). After exposure of mice for 6 hr/day for 5 days, the respiratory tract was examined for histopathologic changes. All irritants produced lesions in the nasal cavity with a distinct anterior-posterior severity gradient. There was considerable variation in the extent, and nature of the lesions. The lesions ranged from slight epithelial hypertrophy or hyperplasia to epithelial erosion, ulceration, and necrosis with variable inflammation of the subepithelial tissues. Only chlorine, chloropicrin, and epichlorohydrin induced lesions in the lower respiratory tract. These findings give additional support to the potential value of the RD50 model for setting occupational exposure guidelines and predicting the risk of injury to the respiratory tract from exposure to airborne sensory irritants.

Pathology of toxic responses to the RD50 concentration of chlorine gas in the nasal passages of rats and mice

Male Swiss-Webster mice and Fischer-344 rats were exposed to chlorine gas at their respective RD50 concentrations (ca. 9 to 11 ppm). The RD50 concentration is that concentration which reduces respiratory rate by 50%. The exposures were carried out for 6 hr per day for 1, 3, or 5 days, and the animals were killed immediately at the end of the last exposure. The nasal passages were examined by light and scanning electron microscopy. Lesions were observed in all exposed groups and were of similar severity and character in rats and mice. The most severe changes were found in the olfactory mucosa of the anterior portion of the dorsal meatus and consisted of partial to complete degeneration of olfactory sensory cells, with olfactory sustentacular cells being more resistant to chlorine exposure. Lesions in the respiratory epithelium were located primarily on the free margins of the naso- and maxilloturbinates and adjacent nasal septum. Scanning electron microscopy, using large size specimens, demonstrated loss of olfactory cilia in areas of the olfactory epithelium which appeared unaffected by light microscopy. Scanning electron microscopy was also helpful in locating areas of respiratory epithelium exhibiting loss of cilia and cellular exfoliation, which occurred primarily on naso- and maxilloturbinates. Therefore, chlorine-induced severe lesions in specific locations in both the olfactory and respiratory epithelia of the nasal passages with more widespread loss of respiratory and olfactory cilia.