Azadirachtin Inhibits Nuclear Receptor HR3 in the Prothoracic Gland to Block Larval Ecdysis in the Fall Armyworm, Spodoptera frugiperda

Azadirachtin has been used to control agricultural pests for a long time; however, the molecular mechanism of azadirachtin on lepidopterans is still not clear. In this study, the fourth instar larvae of fall armyworm were fed with azadirachtin, and then the ecdysis was blocked in the fourth instar larval stage (L4). The prothoracic glands (PGs) of the treated larvae were dissected for RNA sequencing to determine the effect of azadirachtin on ecdysis inhibition. Interestingly, one of the PG-enriched genes, the nuclear hormone receptor 3 (HR3), was decreased after azadirachtin treatment, which plays a critical role in the 20-hydroxyecdysone action during ecdysis. To deepen the understanding of azadirachtin on ecdysis, the HR3 was knocked out by using the CRISPR/Cas9 system, while the HR3 mutants displayed embryonic lethal phenotype; thus, the stage-specific function of HR3 during larval molting was not enabled to unfold. Hence, the siRNA was injected into the 24 h L4 larvae to knock down HR3. After 96 h, the injected larvae were blocked in the old cuticle during ecdysis which is consistent with the azadirachtin-treated larvae. Taken together, we envisioned that the inhibition of ecdysis in the fall armyworm after the azadirachtin treatment is due to an interference with the expression of HR3 in PG, resulting in larval mortality. The results in this study specified the understanding of azadirachtin on insect ecdysis and the function of HR3 in lepidopteran in vivo.

Spin independence of the strongly enhanced effective mass in ultra-clean SiGe/Si/SiGe two-dimensional electron system

The effective mass at the Fermi level is measured in the strongly interacting two-dimensional (2D) electron system in ultra-clean SiGe/Si/SiGe quantum wells in the low-temperature limit in tilted magnetic fields. At low electron densities, the effective mass is found to be strongly enhanced and independent of the degree of spin polarization, which indicates that the mass enhancement is not related to the electrons' spins. The observed effect turns out to be universal for silicon-based 2D electron systems, regardless of random potential, and cannot be explained by existing theories.

Plasma EBV DNA in Nasopharyngeal Cancer (NPC) Treated with Definitive Radiotherapy (RT)

PURPOSE/OBJECTIVE(S)

EBV DNA has well-studied roles in NPC including early detection and surveillance. There are limited North American data on EBV DNA testing. Our center has used EBV DNA testing since 2010. We hypothesized: (1) higher first post-RT EBV DNA level is associated with worse prognosis, and (2) surveillance EBV DNA is specific for recurrence at a low detection threshold.

MATERIALS/METHODS

We retrospectively reviewed all patients with non-metastatic (TNM-7 stage I-IVB) NPC treated with definitive RT/chemoRT (CRT) ± adjuvant chemotherapy (AC) between 2010-2017. EBV DNA was assayed by quantitative PCR in a CAP/CLIA-certified laboratory and reported in copies/mL of plasma. Pre-RT is defined as 0-90 days before the first RT fraction and post-RT within one year after RT. We report log odds ratios (LOR) from a linear model of T- and N-category with log-adjusted EBV DNA as the response variable. Survival outcomes were analyzed with log-rank tests and Cox multivariate analyses (MVA) adjusted for age, stage, and treatment, reporting hazard ratios (HR). A total of 95% confidence intervals of LOR and HR are reported. The detection threshold that maximized the F1 accuracy score was considered optimal.

RESULTS

Of 271 patients in the study window, 179 had pre-RT +/- post-RT EBV DNA testing. Six received RT, 43 CRT, and 130 CRT+AC. With 7-yr median follow-up, 37 recurred and 37 died. Detectable pre-RT EBV DNA was found in 154 (86%) with a median of 928 copies/mL (range: 1-239214). EBV DNA level correlated with higher N category (LOR: 0.28, 0.15-0.42, p<0.001), but not T category (0.04, -0.06-0.13, p = 0.5). Above-median pre-RT EBV DNA was associated with worse recurrence-free survival (RFS) by log-rank test (p = 0.016) and Cox MVA (HR: 2.2, 1.1-4.8, p = 0.03) along with N category, age, and no AC. Post-RT EBV DNA was available in 99 patients at a median of 54 days. RFS, progression-free survival (PFS), and overall survival (OS) were worse in patients with detectable post-RT EBV DNA (Table). RFS and PFS drop further to 20% if EBV DNA was detectable after the full treatment (RT±AC, n = 71). In Cox MVA, post-RT EBV DNA remained independently prognostic (Table). EBV DNA was performed within 30 days of recurrence in 30 patients, and 24 were detectable (80% sensitivity). Conversely, of 152 patients without recurrence and at least 3-yr follow-up, 95 had post-RT EBV DNA testing and 84 were undetectable (88% specificity). An EBV DNA threshold of 31 copies maximized F1 accuracy metric, yielding 74% sensitivity and 97% specificity.

CONCLUSION

Pre-RT EBV DNA is prognostic and associated with higher N-category. Post-RT EBV DNA is a strong, independent predictor of RFS, PFS, and OS; 31 copies/mL may be a useful threshold to detect recurrence.

Dawn of Staging for Head and Neck Soft Tissue Sarcoma: Validation of the Novel 8th Edition AJCC T Classification and Proposed Stage Groupings

PURPOSE/OBJECTIVE(S)

After decades of stagnation, the 8th edition TNM (TNM8) introduced a new T classification for head and neck (HN) soft tissue sarcomas (STS). New size cutoffs of 2 and 4 cm define T1-3, and a novel T4 category is defined by local invasion of adjoining structures. These size cutoffs had been chosen arbitrarily to advance data collection in this unique disease site since literature showed approximately 70% of HN STS did not reach the previous size threshold (5 cm) for the existing T1 category. The definition of the TNM8 T categories also align with mucosal HN cancers. No stage grouping for HN STS was defined since this new classification required more data collection to derive stage groups. This study aims to validate the TNM8 T classification and to propose stage groupings.

MATERIALS/METHODS

Clinical data of all adult (>16 years) HN STS patients treated from 1988 - 2019 with curative intent in our tertiary cancer center were retrieved from a prospective database, and supplemented with chart review. As per TNM8, cutaneous angiosarcoma, embryonal and alveolar rhabdomyosarcoma, Kaposi sarcoma, and dermatofibrosarcoma protuberans were excluded due to their different behavior. Multivariate analysis (MVA) identified prognostic factors for overall survival (OS). Adjusted hazard ratios (AHR) and recursive partitioning analysis (RPA) were used to derive stage groupings. Stage grouping performance for OS was assessed and also compared against the existing TNM8 groups for non-HN STS.

RESULTS

A total of 221 patients (N1: 2; M1: 2) were included. Of the 219 M0 patients, 63% were males; median tumor size was 3.0 cm (range: 0.3-14.0); the proportion of TNM8 T1-T4 were 35%, 34%, 26%, and 5%, respectively. Median follow up was 5.9 years. Five-year OS was 79%. MVA confirmed the prognostic value of T category (T4 HR 7.73, 95% CI 3.62-16.5) and grade (G2/3 vs G1 HR 3.7, 95% CI 1.82-7.53), in addition to age (HR 1.03, 95% CI 1.01-1.04) (all p<0.001) for OS. AHR model derived T1-3_Grade 1 as stage 1; T1-3_Grade 2/3 as stage II; and T4_any Grade or any T_N1 as stage III (Table 1); the corresponding 5-year OS was 93%, 73%, and 38%, respectively. Both patients with M1 died within 1.5 years after diagnosis and M1 disease was designated stage IV. The AHR-grouping outperformed the RPA and non-HN TNM8 stage grouping for hazard consistency, hazard discrimination, percent variance explained, hazard difference, and sample size balance.

CONCLUSION

The novel T4 category introduced in TNM8 is associated with a >7 fold increased risk of death. Grade continues to be a critical prognostic factor in HN STS. The TNM8 HN STS T classifications have been validated, and the proposed new stage groupings with TNM8 incorporating grade have excellent performance for OS.

Outcomes after Contemporary Definitive Radiotherapy Alone in Patients with TNM-7 Stage III/IV Head and Neck Squamous Cell Carcinoma

PURPOSE/OBJECTIVE(S)

This study was undertaken to determine outcomes and prognostic factors of definitive intensity-modulated radiotherapy (IMRT) alone for patients with TNM-7 stage III/IV HNSCC who did not receive concurrent chemotherapy.

MATERIALS/METHODS

We evaluated TNM-7 stage III/IV HNSCC patients treated with definitive IMRT alone in our institution from 2004-2019. Patients were reclassified according to TNM-8 staging. Stage II HPV+ oropharyngeal cancers (OPC) were subdivided into T1-2N2 and T3N0-2 for analysis. The rationale for chemotherapy omission was obtained retrospectively from clinical documentation. Recurrence-free survival (RFS) and overall survival (OS) were estimated stratified by HPV status (determined by p16 staining, sometimes supplemented by HPV DNA testing). Multivariable analysis (MVA) identified prognostic factors for RFS and OS, taking into account stage and IMRT regimen. Age, performance status, and smoking were also examined for OS.

RESULTS

A total of 1083 patients were included (460 HPV+ and 623 HPV-). Reasons for omission of chemotherapy were: age >70 years or frailty (n = 551, 51%), cisplatin contraindication (n = 241, 22%), patient refusal (n = 106, 10%), and clinician's decision (n = 185, 17%). Median age was 67 years for HPV+ and 70 years for HPV- cohorts. IMRT mostly utilized altered fractionation regimens (n = 1016, 94%): moderately accelerated (Acc) (70 Gy/35 fractions [f]/6 weeks [w], 55%), hypofractionated (Hypo) (60 Gy/25f/5w, 14%), and hyperfractionated-accelerated (Hyper) (64 Gy/40f/4w, 25%). Median follow-up was 5 years. Five-year RFS and OS for HPV+ TNM-8 stage I/T1-2N2/T3N0-N2/III were 89%/86%/76%/52% and 83%/80%/64%/33% respectively (p<0.01). The same outcomes for HPV- TNM-8 stage III/IVA/IVB were 58%/52%/39% and 47%/27%/13%, respectively (p<0.01). MVA confirmed that HPV+ T3N0-2 subset within stage II and stage III (vs stage I) had lower RFS, and HPV- stage IVA and IVB (vs stage III) carried worse RFS and OS (Table).

CONCLUSION

Despite the retrospective nature and inherent selection bias, this large single institutional study shows that altered fractionated IMRT alone is an acceptable alternative for elderly, frail or cisplatin ineligible patients with HPV+ stage I/IIA (T1-2N2) OPC. Patients with HPV+ T3N0-2/stage III OPC and HPV- stage III/IV HNSCC have poor outcomes with IMRT alone and may benefit from alternative strategies.

The Prognostic and Predictive Value of Pre-Treatment Total Lymphocyte Count in HPV+ Oropharyngeal Carcinoma Receiving Definitive (Chemo-) Radiation

PURPOSE/OBJECTIVE(S)

Evidence of prognostic importance of pre-radiotherapy (RT) total lymphocyte counts (TLC) and interaction with addition of cisplatin (CRT) in HPV-positive oropharyngeal carcinoma (HPV+OPC) is conflicting. Recent data suggest patients with high TLC may not benefit from the addition of chemotherapy (Price et al, JCO 2022). We assess the prognostic and predictive value of TLC in a large single center HPV+OCP cohort.

MATERIALS/METHODS

All HPV+OPC patients treated at a single academic center with definitive RT/CRT between 2005-2018 were included. Pre-treatment TLC up to 6 weeks prior to RT start were considered. Multivariable analysis (MVA) was applied to assess the prognostic importance of TLC (continuous variable), adjusted for age, gender, performance status, TNM-8 stage, and smoking status in the CRT and RT subgroups. The actuarial rates of locoregional control (LRC), distant control (DC), and overall survival (OS) were calculated using Kaplan-Meier and competing risk methods, stratified by low vs high TLC (determined using Contal and O'Quigley method for optimal cutoff).

RESULTS

Among 1153 eligible patients, 707 (61%) were treated with CRT. Median age was 59.7 (range 22.7-92.2) years. 526 patients were (46%) TNM-8 stage I, 366 (32%) stage II and 261 (23%) stage III. Median TLC was 1.6 x 109/L (range 0.1-8.5). Median follow-up was 5.5 years. On MVA, TLC was prognostic for patients receiving CRT (OS [adjusted hazard ration (aHR) 0.55 (0.38-0.79), p = 0.002], DC [aHR 0.57 (0.37-0.88), p = 0.011], LRC [aHR 0.57 (0.36-0.89), p = 0.014]) but not RT (OS [aHR 1.04 (0.82-1.31), p = 0.74], LRC [aHR 1.26 (0.86-1.85), p = 0.23], DC [aHR 0.87 (0.64-1.19), p = 0.4)]. The optimal TLC cut-off for OS with CRT was 1.9 x 109/L. Low vs high TLC patients receiving CRT had significantly inferior 5-year DC (87% vs 93%, p = 0.017) and OS (84% vs 90%, p = 0.026). The benefit of higher TLC was most evident in stage II disease (table 1). CRT vs RT improved OS for stage II/III disease at high and low TLC.

CONCLUSION

Pre-treatment TLC is prognostic in a large cohort of HPV+OPC patients receiving CRT but not RT alone. Further investigation of the interaction of cisplatin and immune response during RT is warranted. The omission of chemotherapy based on TLC is not supported.

Outcomes of Head and Neck Cutaneous Angiosarcoma Treated in the IMRT Era

PURPOSE/OBJECTIVE(S)

Clinical behavior, natural history, and varied presentations of cutaneous angiosarcomas of the head and neck region (HN), in conjunction with its rarity, have rendered standardization of treatment elusive. We aimed to assess outcomes and patterns of failure for patients treated with surgery and radiation (Sx+RT), and radiation alone (RT).

MATERIALS/METHODS

A retrospective review of all HN angiosarcoma patients amenable for upfront Sx or RT in our institution between 2004-2018 was completed. Generally, treatment included Sx when feasible, and RT for large or extensive/ill-defined tumors. Demographic, tumor characteristics, local (LC), regional (RC), distant control (DC), and overall survival (OS), as well as patterns (in-field, marginal, out-of-field) of local failure at 5-year were estimated. Univariate analysis (UVA) was conducted to assess association with outcomes.

RESULTS

A total of 33 patients were eligible (14 Sx+RT and 19 RT). Tumor locations were: scalp (16, 48%). face (n = 12, 36%), and overlapping (5, 15%). Lesion types were: nodular (n = 23, 70%), flat (n = 4, 12%) and mixed (n = 6, 18%). Tumor size was larger in the RT group (median: 10.00 vs 2.85 cm, p<0.01). RT and Sx+RT patients had otherwise similar baseline characteristics: median age 74.3; male 70%; and ECOG performance status ≤1 85%. RT dose fractionations ranged from 50-70 Gy in 25-35 fractions in the RT group and 50-66 Gy in 25-33 fractions in the Sx+RT group. Four (12%) patients received neoadjuvant chemotherapy. Median follow up was 5.5 years. Five-year LC, RC, DC, and OS for RT vs Sx+RT groups were 68% vs 85% (p = 0.28); 95% vs 86% (p = 0.89); 79% vs 86% (p = 0.39); and 45% vs 55% (p = 0.71), respectively. The in-field/marginal/out-of-field local failure rate at 5 years were 16% vs 7% (p = 0.46), 26% vs 15% (p = 0.41), and 13% vs 0% (p = 0.24) for the RT vs Sx+RT groups, respectively. UVA showed that scalp location and ulceration/bleeding were strong adverse features for OS. Bone invasion was significantly associated with lower DC (Table). Lesion type (nodular/flat/mixed), tumor size, and treatment type (Sx+RT vs RT), were not significantly associated with LC or pattern of local failure.

CONCLUSION

Scalp tumors, as compared to face, portended poorer prognosis, and ulceration/bleeding and bone invasion were associated with increased distant metastases. Sx+RT was the preferred treatment modality when possible and typically used for smaller and better defined tumors. RT was reserved for larger and extensive/ill-defined disease; despite this, in the IMRT era, RT achieves reasonable rates of control, markedly superior to historical series.

[Anatomical classification of and laparoscopic surgery for left-sided colorectal cancer with persistent descending mesocolon]

Objective: To investigate anatomical morphology and classification of persistent descending mesocolon (PDM) in patients with left-sided colorectal cancer, as well as the safety of laparoscopic radical surgery for these patients. Methods: This is a descriptive study of case series. Relevant clinical data of 995 patients with left colon and rectal cancer who had undergone radical surgery in Fujian Medical University Union Hospital from July 2021 to September 2022 were extracted from the colorectal surgery database of our institution and retrospectively analyzed. Twenty-four (2.4%) were identified as PDM and their imaging data and intra-operative videos were reviewed. We determined the distribution and morphology of the descending colon and mesocolon, and evaluated the feasibility and complications of laparoscopic surgery. We classified PDM according to its anatomical characteristics as follows: Type 0: PDM combined with malrotation of the midgut or persistent ascending mesocolon; Type 1: unfixed mesocolon at the junction between transverse and descending colon; Type 2: PDM with descending colon shifted medially (Type 2A) or to the right side (Type 2B) of the abdominal aorta at the level of the origin of the inferior mesentery artery (IMA); and Type 3: the mesocolon of the descending-sigmoid junction unfixed and the descending colon shifted medially and caudally to the origin of IMA. Results: The diagnosis of PDM was determined based on preoperative imaging findings in 9 of the 24 patients (37.5%) with left-sided colorectal cancer, while the remaining diagnoses were made during intraoperative assessment. Among 24 patients, 22 were male and 2 were female. The mean age was (63±9) years. We classified PDM as follows: Type 0 accounted for 4.2% (1/24); Type 1 for 8.3% (2/24); Types 2A and 2B for 37.5% (9/24) and 25.0% (6/24), respectively; and Type 3 accounted for 25.0% (6/24). All patients with PDM had adhesions of the mesocolon that required adhesiolysis. Additionally, 20 (83.3%) of them had adhesions between the mesentery of the ileum and colon. Twelve patients (50.0%) required mobilization of the splenic flexure. The inferior mesenteric artery branches had a common trunk in 14 patients (58.3%). Twenty-four patients underwent D3 surgery without conversion to laparotomy; the origin of the IMA being preserved in 22 (91.7%) of them. Proximal colon ischemia occurred intraoperatively in two patients (8.3%) who had undergone high ligation at the origin of the IMA. One of these patients had a juxta-anal low rectal cancer and underwent intersphincteric abdominoperineal resection because of poor preoperative anal function. Laparoscopic subtotal colectomy was considered necessary for the other patient. The duration of surgery was (260±100) minutes and the median estimated blood loss was 50 (20-200) mL. The median number of No. 253 lymph nodes harvested was 3 (0-20), and one patient (4.2%) had No.253 nodal metastases. The median postoperative hospital stay was 8 (4-23) days, and the incidence of complications 16.7% (4/24). There were no instances of postoperative colon ischemia or necrosis observed. One patient (4.2%) with stage IIA rectal cancer developed Grade B (Clavien-Dindo III) anastomotic leak and underwent elective ileostomy. The other complications were Grade I-II. Conclusions: PDM is frequently associated with mesenteric adhesions. Our proposed classification can assist surgeons in identifying the descending colon and mesocolon during adhesion lysis in laparoscopic surgery. It is crucial to protect the colorectal blood supply at the resection margin to minimize the need for unplanned extended colectomy, the Hartmann procedure, or permanent stomas.

[Anatomical and histological investigation of the area anterior to the anorectum passing through the levator hiatus]

Objective: To document the anatomical structure of the area anterior to the anorectum passing through the levator hiatus between the levator ani slings bilaterally. Methods: Three male hemipelvises were examined at the Laboratory of Clinical Applied Anatomy, Fujian Medical University. (1) The anatomical assessment was performed in three ways; namely, by abdominal followed by perineal dissection, by examining serial cross-sections, and by examining median sagittal sections. (2) The series was stained with hematoxylin and eosin to enable identification of nerves, vessels, and smooth and striated muscles. Results: (1) It was found that the rectourethralis muscle is closest to the deep transverse perineal muscle where the longitudinal muscle of the rectum extends into the posteroinferior area of the membranous urethra. The communicating branches of the neurovascular bundle (NVB) were identified at the posterior edge of the rectourethralis muscle on both sides. The rectum was found to be fixed to the membranous urethra through the rectourethral muscle, contributing to the anorectal angle of the anterior rectal wall. (2) Serial cross-sections from the anal to the oral side were examined. At the level of the external anal sphincter, the longitudinal muscle of the rectum was found to extend caudally and divide into two muscle bundles on the oral side of the external anal sphincter. One of these muscle bundles angled dorsally and caudally, forming the conjoined longitudinal muscle, which was found to insert into the intersphincteric space (between the internal and external anal sphincters). The other muscle bundle angled ventrally and caudally, filling the gap between the external anal sphincter and the bulbocavernosus muscle, forming the perineal body. At the level of the superficial transverse perineal muscle, this small muscle bundle headed laterally and intertwined with the longitudinal muscle in the region of the perineal body. At the level of the rectourethralis and deep transverse perineal muscle, the external urethral sphincter was found to occupy an almost completely circular space along the membranous part of the urethra. The dorsal part of the external urethral sphincter was found to be thin at the point of attachment of the rectourethralis muscle, the ventral part of the longitudinal muscle of the rectum. We identified a venous plexus from the NVB located close to the oral and ventral side of the deep transverse perineal muscle. Many vascular branches from the NVB were found to be penetrating the longitudinal muscle and the ventral part of rectourethralis muscle at the level of the apex of the prostate. The rectourethral muscle was wrapped ventrally around the membranous urethra and apex of the prostate. The boundary between the longitudinal muscle and prostate gradually became more distinct, being located at the anterior end of the transabdominal dissection plane. (3) Histological examination showed that the dorsal part of the external urethral sphincter (striated muscle) is thin adjacent to the striated muscle fibers from the deep transverse perineal muscle and the NVB dorsally and close by. The rectourethral muscle was found to fill the space created by the internal anal sphincter, deep transverse perineal muscle, and both levator ani muscles. Many tortuous vessels and tiny nerve fibers from the NVB were identified penetrating the muscle fibers of the deep transverse perineal and rectourethral muscles. The structure of the superficial transverse perineal muscle was typical of striated muscle. These findings were reconstructed three-dimensionally. Conclusions: In intersphincteric resection or abdominoperineal resection for very low rectal cancer, the anterior dissection plane behind Denonvilliers' fascia disappears at the level of the apex of the prostate. The prostate and both NVBs should be used as landmarks during transanal dissection of the non-surgical plane. The rectourethralis muscle should be divided near the rectum side unless tumor involvement is suspected. The superficial and deep transverse perineal muscles, as well as their supplied vessels and nerve fibers from the NVB. In addition, the cutting direction should be adjusted according to the anorectal angle to minimize urethral injury.

[The value of MR diffusion tensor imaging in assessing white matter changes in short-term methamphetamine withdrawal]

Objective: To explore the value of MRI diffusion tensor imaging (DTI) in the white matter changes of short-term methamphetamine (MA) abstinence. Methods: The data of DTI, demographics features, general information of addiction and impulsivity scale eleven (BIS-11) of 55 short-term MA addicts who were from Changsha, Zhuzhou and Yueyang compulsory detoxification centers in Hunan province, including 40 males and 15 females, aged 14-45 (37.24±7.31) years old, and 52 healthy controls, including 40 males and 12 females aged 18-59 (40.3±9.1) years were collected prospectively from August 2017 to December 2018. The differences of DTI indicators between the two groups were compared by tract-based spatial statistics (TBSS), and then the correlation between the different indicators and the age of first MA use, time of MA use, daily dose used, BIS-11 score were performed. Results: There were significant differences in BIS total score(P<0.001), BIS motivational impulsivity(P<0.001) and BIS attentional impulsivity(P=0.003) between MA group and healthy control group in short-term withdrawal. And compared with the healthy control group, the fractional anisotropy (FA) (0.58±0.02 vs 0.56±0.02,0.77±0.02 vs 0.75±0.04,0.79±0.04 vs 0.76±0.06; all P<0.05), axial diffusivity (AD) (0.57±0.01 vs 0.56±0.02,P=0.001) and mean diffusivity (MD) (0.66±0.02 vs 0.65±0.02,0.52±0.07 vs 0.51±0.06; both P<0.05)values in the MA group were all increased (P<0.05), but there was no significant difference in the radial diffusivity (RD) value (P>0.05). The white matter areas with increased FA value were located in the knee and body of corpus callosum, bilateral anterior corona radiata and left superior corona radiata; the areas with increased AD value were located in the knee, body and pressure of corpus callosum, bilateral anterior limb of internal capsule, posterior limb of internal capsule, anterior, superior and posterior corona radiata, external capsule and superior longitudinal fasciculus; and the areas with increased MD value were mainly located in the right superior longitudinal fasciculus, anterior and posterior limb of internal capsule. The corpus callosum, where there was a difference in FA between the two groups, was positively correlated with the daily dose of MA (r=0.301, P=0.026). Conclusion: MA addicted individuals with short-term withdrawal have white matter edema and damage, and the degree of corpus callosum damage is positively correlated with the daily dose of MA,which is helpful to understand the pathophysiological process of white matter damage in the nervous system and the potential mechanism of neuropsychiatric symptoms in short-term withdrawal MA addicted individuals.

[Delayed gastric emptying after surgery for transverse colon cancer: diagnosis, management and prevention]

Delayed gastric emptying is a syndrome of gastric motility disorder with slow gastric emptying as the main sign, provided that mechanical factors such as intestinal obstruction and anastomotic stricture are excluded. The incidence of delayed gastric emptying after colon cancer surgery is 1.4%, mainly after transverse colon cancer surgery. Most of the studies on delayed gastric emptying are case reports, lacking systematic studies. The diagnoses and treatments can be draw on the experience of delayed gastric emptying after pancreatic surgery. Our retrospective study indicated that the incidence of delayed gastric emptying after surgery for transverse colon cancer was 4.0%, higher than that for other colon cancer. Patients who underwent gastrocolic ligament lymph node dissection were at higher risk than those who did not (3.6% vs. 0.8%). Gastrocolic ligament lymph node dissection and stress are causative factors for delayed gastric emptying after surgery for transverse colon cancer. We add the gastrografin test upon the diagnostic criteria of the International Study Group for Pancreatic Surgery, which is simple and practical. Nasogastric tube decompression, enteral nutrition combined with parenteral nutrition, glucocorticoids, and prokinetic agents can cure most patients with postoperative delayed gastric emptying. All the patients with postoperative delayed gastric emptying were cured in our studies. Strict indications for gastrocolic ligament lymph node dissection (patients with cT3-4 and cN+) may decrease the occurrence of delayed gastric emptying after surgery for transverse colon cancer.

[Prevalence and influencing factors of Enterobius vermicularis infections among children in Fanxian County of Henan Province in 2019]

OBJECTIVE

To investigate the prevalence and influencing factors of Enterobius vermicularis infections among children in Fanxian County, Henan Province in 2019, so as to provide insights into the management of enterobiasis.

METHODS

Five kindergartens were selected in urban and rural areas of Fanxian County, Henan Province using the stratified sampling method in 2019, and a census of E. vermicularis infections was performed among all children in the kindergartens. E. vermicularis eggs were detected using adhesive and scotch cellophane-tape anal swab methods, and the basic characteristics of children and their families, health habits and the kindergartens' information were investigated with questionnaires. Logistic regression analysis was used to investigate the risk factors and protective factors of pinworm infection in children.

RESULTS

A total of 671 children were tested, and the mean prevalence of E. vermicularis infections was 15.50% (104/671). The prevalence of E. vermicularis infections was higher among children in rural kindergartens (28.13%, 72/256) than in urban kindergartens (7.71%, 32/415) (χ² = 50.380, P < 0.01), and greater in private kindergartens (32.26%, 60/186) than in public kindergartens (9.07%, 44/485) (χ² = 55.183, P < 0.01). There was no gender-specific prevalence of E. vermicularis infections among children (χ² = 1.442, P > 0.05), and the prevalence of E. vermicularis infections presented a tendency towards a rise with age (χ²_trend = 8.373, P < 0.05) and school grade (χ²_trend = 30.274, P < 0.05). Logistic regression analysis identified rural kindergartens and high grades as risk factors, and separate washing of children's and adults' cloths, frequent bathing and frequent dinnerware disinfection in kindergartens as protective factors for E. vermicularis infections among children. In addition, there was no significant difference in the detection of E. vermicularis infections among children by using adhesive (73.08%, 76/104) and scotch cellophane-tape anal swab methods (56.73%, 59/104) (χ² = 3.959, P > 0.05).

CONCLUSIONS

The prevalence of E. vermicularis infection is high among children in Fanxian Country, Henan Province. Health education and surveillance of enterobiasis are required to be intensified among children in rural kindergartens and senior grades and their parents and teachers.

The Potential Impact and Usability of the Eighth Edition TNM Staging Classification in Oral Cavity Cancer

AIMS

In the current eighth edition head and neck TNM staging, extranodal extension (ENE) is an adverse feature in oral cavity squamous cell cancer (OSCC). The previous seventh edition N1 with ENE is now staged as N2a. Seventh edition N2+ with ENE is staged as N3b in the eighth edition. We evaluated its potential impact on patients treated with surgery and postoperative intensity-modulated radiotherapy (IMRT).

MATERIALS AND METHODS

OSCC patients treated with primary surgery and adjuvant (chemo)radiotherapy between January 2005 and December 2014 were reviewed. Cohorts with pathological node-negative (pN-), pathological node-positive without ENE (pN+_pENE-) and pathological node-positive with ENE (pN+_pENE+) diseases were compared for local control, regional control, distant control and overall survival. The pN+ cohorts were further stratified into seventh edition N-staging subgroups for outcomes comparison.

RESULTS

In total, 478 patients were evaluated: 173 pN-; 159 pN+_pENE-; 146 pN+_pENE+. Outcomes at 5 years were: local control was identical (78%) in all cohorts (P = 0.892), whereas regional control was 91%, 80% and 68%, respectively (P < 0.001). Distant control was 97%, 87%, 68% (P < 0.001) and overall survival was 75%, 53% and 39% (P < 0.001), respectively. Overall survival for N1 and N2a subgroups was not significantly different. In the seventh edition N2b subgroup of pENE- (n = 79) and pENE+ (n = 79) cohorts, overall survival was 67% and 37%, respectively. In the seventh edition N2c subgroups, overall survival for pENE- (n = 17) and pENE+ (n = 38) cohorts was 65% and 35% (P = 0.08), respectively. Overall, an additional 128 patients (42% pN+) were upstaged as N3b.

CONCLUSIONS

When eighth edition staging was applied, stage migration across the N2-3 categories resulted in expected larger separations of overall survival by stage. Patients treated with primary radiation without surgical staging should have outcomes carefully monitored. Strategies to predict ENE preoperatively and trials to improve the outcomes of pENE+ patients should be explored.

[Construction of artificial neural network model for predicting the efficacy of first-line FOLFOX chemotherapy for metastatic colorectal cancer]

Objective: To explore and establish an artificial neural network (ANN) model for predicting the efficacy of first-line FOLFOX chemotherapy for metastatic colorectal cancer. Methods: A set of FOLFOX chemotherapy data from a group of patients with metastatic colorectal cancer (mCRC) (GSE104645) was downloaded from the GEO database as a training set. According to the FOLFOX protocol, the efficacy was divided into two groups: the chemo-sensitive group (including complete response and partial response) and the chemo-resistant group (including stable disease and progressive disease), including 31 cases in the sensitive group and 23 in the resistant group. Then, chip data (accessible number: GSE69657) from Fujian Medical University Union Hospital were chosen as a test set. A total of 30 patients were enrolled in the study, including 13 in the sensitive group and 17 in the resistant group. The batch effect correction was performed on the expression values of the two sets of matrices using the R 3.5.1 software Combat package. The gene expression difference of sensitive and resistant group in GSE104645 was analyzed by the GEO2R platform. P<0.05 and the absolute value of log(2)FC>0.33 (FC abbreviation of fold change) were used as the threshold value to screen the drug resistance and sensitive genes of the FOLFOX regimen. An ANN was constructed using the multi-layer perceptron (MLP) to perform the FOLFOX regimen on the GSE104645 dataset. The GSE69657 expression matrix and clinical efficacy parameters were then used for retrospective verification. Receiver operating characteristic(ROC) curves were used to evaluate the test results and predictive power. Results: A total of 2, 076 differentially expressed genes in GSE104645 were selected, of which 822 genes were up-regulated and 1, 254 genes were down-regulated in the chemo-resistance group. The down-regulated genes were sensitive genes. GO analysis of the biological processes in which the differentially expressed genes were involved, revealed that they were mainly involved in the regulation of substance metabolism. A total of 39 genes were included in the final model construction. This was a neural network model with two hidden layers. The accuracy of predicting training samples and test samples was 75.7% and 76.5%, respectively, and the area under the ROC curve was 0.875. The chip data set of our department (GSE69657) was set as the test set, and the area under the ROC curve was 0.778. Conclusions: In this study, an artificial neural network model is successfully constructed to predict the efficacy of first-line FOLFOX regimen for metastatic colorectal cancer based on the microarray, and an independent external verification is also conducted. The model has good stability and well prediction efficiency. Besides, the results of this study suggest that the gene functions related to oxaliplatin resistance are mainly enriched in the regulation process of substance metabolism.

[Rectum-preserving surgery after consolidation neoadjuvant therapy or totally neoadjuvant therapy for low rectal cancer: a preliminary report]

Objective: To investigate the feasibility and safety of sphincter-preserving surgery after neoadjuvant chemoradiotherapy (nCRT) with consolidation chemotherapy in the interval period or total neoadjuvant therapy (TNT) for low rectal cancer. Methods: A descriptive case series study was carried out. Clinical data of patients with locally advanced low rectal cancer (LALRC) who achieved complete clinical response (cCR) or nearly cCR (near-cCR) after nCRT at the Department of Colorectal Surgery of Fujian Medical University Union Hospital from May 2015 to February 2019 were retrospectively analyzed. Case inclusion criteria: (1) Low rectal adenocarcinoma within 6 cm from the anal verge. (2) After nCRT, tumor presented markedly regression as mucosal nodule or abnormalities, superficial ulcer, scar or a mucosal erythema (< 2 cm); no regional lymph node metastasis or distant metastasis was found in rectal ultrasonography, pelvic MRI and PET-CT; MRI showed obvious fibrosis in the original tumor site; and post-treatment CEA was normal. (3) The patient and the family members adhered to receive the transanal full-thickness local excision with informed consent. (4) When the residual lesions were difficult to detect after nCRT, patients received the watch and wait (W&W) strategy. Exclusion criteria: (1) Before nCRT, pathological results showed poorly differentiated or signet-ring cell carcinoma; lateral lymph node metastasis was suspected. (2) When the residual lesion size was more than 3 cm after nCRT, it was difficult to perform local excision. The consolidation nCRT group received 3-4 cycles of CAPOX regimen (oxaliplatin and capecitabine) or six cycles of mFOLFOX6 (oxaliplatin, leucovorin, and 5-fluorouracil) combined with the long-course radiotherapy (intensity-modulated radiation therapy with a total dose of 50.4Gy). Patients with concurrent chemotherapy more than or equal to five cycles of CAPOX or eight cycles of mFOLFOX6 were defined as total neoadjuvant therapy (TNT) group. Local resection was recommended for patients who were near-cCR according to modified MSKCC criteria 8-33 weeks after the end of radiotherapy. Patients with a near-cCR, who were judged as ycN0 according to PET-CT and MRI and were ypT0 after local excision, could enter the W&W strategy. Patients with pathologic stage more advanced than ypT1, and those with positive resection margin, or lymphovascular invasion were recommended for salvage radical surgery after local excision. The ypT1 patients with a negative resection margin and without lymphovascular invasion might receive the W&W management carefully if they refused radicalsurgery to sacrifice the sphincter for low rectal cancer. Results: Of 32 patients, 14 were males and 18 were females with the average age of 59 years old. Twenty-three patients underwent consolidation nCRT, and 9 received TNT. The first evaluation after treatments showed 19 cases with cCR and 13 with near-cCR. Twenty-nine patients received local excision while 3 patients with undetectable lesions received W&W policy. Four cases (12.5%) underwent salvage radical surgery with abdominoperineal resection. After local excision, 3 cases underwent salvage radical surgery immediately, and the final pathologic result was ypT3N0, ypT2N0, and ypT2N0 respectively, of whom 2 cases were in the group of consolidation CRT and 1 was in the TNT group. Of these 3 cases, 1 case with an initial cT3 stage showed a pathologic stage of ypT1 and a negative circumferential resection margin after consolidation nCRT and local excision, however, the final pathologic stage was ypT3 with fragmented tumor deposits in the mesorectum after the salvage radical surgery. Meanwhile 1 patient in the TNT group receiving W&W suffered from intraluminal regrowth after 7.4 months follow-up and underwent salvage abdominoperineal resection. One patient in the consolidation nCRT group died of stroke 42.5 months after local resection. Another patient in the TNT group had cerebral metastasis 10 months after the W&W policy, but no local recurrence was found in the pelvic cavity, then received resection of the metastatic tumors. The average follow-up for all the patients was 23 (5-51) months. The cumulative local regrowth rate was 5.0%. The overall survival rate was 85.7%, and the sphincter-preservation rate was increased from 25.0% (28/32) in the original plan to 87.5% (28/32) actually. The 3-year disease-free survival rate was 89.7%. The 3-year organ-preserving survival rate was 85.7%, and the 3-year stoma-free survival rate was 82.5%. At present, 31 patients still survived. Conclusions: After nCRT with consolidation chemotherapy or TNT for low rectal cancer, patients with cCR, ycN0 according to PET-CT and MRI, and ypT0 after local excision, can consider the W&W strategy. Strict patient selection with a near-cCR for local resection and sphincter-preserving strategy can reduce the local regrowth of cancer, and the short-term outcomes are satisfactory.

Development and validation of a clinical prediction-score model for distant metastases in major salivary gland carcinoma

BACKGROUND

The most common pattern of failure in major salivary gland carcinoma (SGC) is development of distant metastases (DMs). The objective of this study was to develop and validate a prediction score for DM in SGC.

PATIENTS AND METHODS

Patients with SGC treated curatively at four tertiary cancer centers were divided into discovery (n = 619) and validation cohorts (n = 416). Multivariable analysis using competing risk regression was used to identify predictors of DM in the discovery cohort and create a prediction score of DM; the optimal score cut-off was determined using a minimal P value approach. The prediction score was subsequently evaluated in the validation cohort. The cumulative incidence and Kaplan-Meier methods were used to analyze DM and overall survival (OS), respectively.

RESULTS

In the discovery cohort, DM predictors (risk coefficient) were: positive margin (0.6), pT3-4 (0.7), pN+ (0.7), lymphovascular invasion (0.8), and high-risk histology (1.2). High DM-risk SGC was defined by sum of coefficients greater than two. In the discovery cohort, the 5-year incidence of DM for high- versus low-risk SGC was 50% versus 8% (P < 0.01); this was similar in the validation cohort (44% versus 4%; P < 0.01). In the pooled cohorts, this model performed similarly in predicting distant-only failure (40% versus 6%, P < 0.01) and late (>2 years post surgery) DM (22% versus 4%; P < 0.01). Patients with high-risk SGC had an increased incidence of DM in the subgroup receiving postoperative radiation therapy (46% versus 8%; P < 0.01). The 5-year OS for high- versus low-risk SGC was 48% versus 92% (P < 0.01).

CONCLUSION

This validated prediction-score model may be used to identify SGC patients at increased risk for DM and select those who may benefit from prospective evaluation of treatment intensification and/or surveillance strategies.

[Identification of gene biomarkers to predict responses to neoadjuvant chemoradiotherapy in patients with rectal cancer and pathways enrichment analysis]

Objective: To screen out the potential gene biomarkers to predict responses to neoadjuvant chemoradiotherapy (CRT) in patients with rectal cancer and to explore the main downstream pathways of resistance. Methods: The gene expression profiles (GSE35452) of locally advanced rectal cancer undergoing neoadjuvant chemoradiotherapy from 46 specimens (24 responders, TRG 0/1, and 22 non-responders, TRG 2/3) were downloaded from the GEO database. The differentially expressed genes were identified to screen out the potential biomarkers by use of the GCBI platform. GO and KEGG pathways enrichment analysis were performed to integrate enrichment results of differentially expressed genes. Signal-signal interaction network was constructed and analyzed to screen out potential main downstream pathways. Results: A total of 1079 differentially expressed genes were screened, including 657 up-regulated and 422 down-regulated ones. Among these genes, REG4 had the maximum fold change value of -6.029 491. In GO term, these differentially expressed genes were mainly enriched in molecule metabolic process, cell cycle, DNA-dependent transcription, signal transduction and apoptotic process. The KEGG pathways enrichment analysis showed that the differentially expressed genes were enriched in 65 KEGG pathways, including metabolic pathways, cell cycle and metabolism pathways. Signal-signal interaction network analysis showed that MAPK signaling pathway and cell cycle pathway might play a determinant role in the development of neoadjuvant chemoradiotherapy resistance. Further analysis showed that CDKN1B, CDKN2A, RBL1, TFDP1, CCND2, CCNE2, CDC6 and CDK6 in cell cycle might induce chemoradiotherapy resistance by blocking G1/S phase cell cycle arrest, decreasing the apoptosis of tumor cells and increasing S phase ratio of chemoradiotherapy resistance. Conclusion: G1/S phase cell cycle arrest blocking plays an important role in the development of chemoradiotherapy resistance in patients with rectal cancer. Moreover, the key genes, such as REG4, may be useful in predicting responses to neoadjuvant chemoradiotherapy.

[Effects of artesunate combined with bortezomib on apoptosis and autophagy of acute myeloid leukemia cells in vitro and its mechanism]

Objective: To investigate the effects of artesunate combined with bortezomib on the proliferation, apoptosis and autophagy of human acute myeloid leukemia cell lines MV4-11, and its mechanisms. Methods: MTT method was used to determine the anti-proliferation effect of different concentrations of artesunate, bortezomib and their combination on MV4-11 cells. The cell apoptosis were analyzed by flow cytometry. The expression of cleaved-Caspase-3, Bcl-2 family protein (Bcl-2, Mcl-1, Bim, Bax) and autophagy-related protein LC3B were assayed by Western blot. Results: Artesunate displayed a proliferation inhibition effect on MV4-11 with dose- and time-dependent manner, the IC(50) of artesunate on MV4-11 after 48 hours was 1.44 μg/ml. Bortezomib displayed a proliferation inhibition effect on MV4-11 with dose-dependent manner, the IC(50) of bortezomib on MV4-11 after 48 hours was 8.97 nmol/L. The combination of artesunate (0.75, 1.0 μg/ml) and Bortezomib (6, 8 nmol/L) showed higher inhibition on MV4-11 than artesunate or bortezomib alone in the same concentration gradient after 48 hours (P<0.05) . The cooperation index of the two drugs were all less than 1. The 48 h apoptotic rate of artesunate (1.5 μg/ml) on MV4-11 was (15.27±2.18) %, (19.85±3.23) % of bortezomib (8 nmol/L) , (81.67±5.96) % of combination of the two drugs, significantly higher than the single group (P<0.05) . When combination of the two drugs on MV4-11 after 24 hours, the levels of pro-apoptotic protein Bim and the cleaved activation of Caspase-3 and autophagy-related protein LC3B were up-regulated and the anti-apoptotic protein Bcl-2 expressions was down-regulated. Conclusion: Combination of artesunate with bortezomib shows a significant synergistic effects on proliferation, apoptosis and autophagy of MV4-11 cell lines, which may be associated with Bcl-2 family proteins expression.

Aclidinium bromide inhibits human glioma cell proliferation, migration and invasion and promotes apoptosis via the PI3K/AKT signaling pathway

This study investigates the anti-cancer potential of Aclidinium bromide (INN) in glioblastoma. Glioblastoma cell lines U251 and U87 were treated with INN and its effects on cell migration and invasion were assessed by transwell migration and invasion assays., The effects of INN on proliferation and apoptosis were detected by CCK-8 kit and flow cytometry, and Western blotting determined anti-apoptotic proteins and signaling pathway changes. The results show that INN effectively suppressed proliferation, migration and invasion and induced apoptosis in U251 and U87 cells, respectively. Furthermore, the expression levels of the Bcl-2 anti-apoptotic protein was significantly decreased while Bax and caspase-3 expression were both increased in glioblastoma cells (all, p<0.05). Moreover, INN inactivated the PI3K/AKT signaling pathway by down-regulating the level of p-AKT, p-mTOR, P70 and CyclinD1 (all, p<0.05). In conclusion, our data suggests that INN could provide novel anticancer therapy in the treatment of glioblastoma.

Radiologic-Pathologic Correlation of Tumor Thickness and Its Prognostic Importance in Squamous Cell Carcinoma of the Oral Cavity: Implications for the Eighth Edition Tumor, Node, Metastasis Classification

BACKGROUND AND PURPOSE

Addressing the performance of an imaging-based parameter compared to a "gold standard" pathologic measurement is essential to achieve accurate clinical T-classification. Our aim was to determine the radiologic-pathologic tumor thickness correlation and its prognostic value in oral squamous cell carcinoma.

MATERIALS AND METHODS

All pathologic T1-T3 (seventh edition of the Cancer Staging Manual of the American Joint Committee on Cancer) oral squamous cell carcinomas diagnosed between 2010 and 2015 were reviewed. Radiologic tumor thickness was measured on preoperative CT or MR imaging blinded to pathology. The radiologic-pathologic tumor thickness correlation was calculated. The impact of the imaging-to-surgery time interval and imaging technique on the correlation was explored. Intra-/interrater reliability on radiologic tumor thickness was calculated. The correlation of radiologic-versus-pathologic tumor thickness and its performance as the seventh edition T-category modifier was evaluated. Multivariable analysis assessed the prognostic value of the radiologic tumor thickness for overall survival adjusted for age, seventh edition T-category, and performance status.

RESULTS

For 354 consecutive patients, the radiologic-pathologic tumor thickness correlation was similar for the image-to-surgery interval of ≤4.0 weeks (ρ = 0.76) versus 4-8 weeks (ρ = 0.80) but lower in those with more than an 8-week interval (ρ = 0.62). CT and MR imaging had similar correlations (0.76 and 0.80). Intrarater and interrater reliability was excellent (0.88 and 0.84). Excluding 19 cases with an imaging-to-surgery interval of >8 weeks, 335 patients were eligible for further analysis. The radiologic-pathologic tumor thickness correlation was 0.78. The accuracy for upstaging the T-classification based on radiologic tumor thickness was 83% for pathologic T1 and 74% for pathologic T2 tumors. Multivariable analysis confirmed the prognostic value of radiologic tumor thickness (hazard ratio = 1.5, P = .02) for overall survival.

CONCLUSIONS

This study demonstrates a good radiologic-pathologic tumor thickness correlation. Intrarater and interrater reliability for radiologic tumor thickness was excellent. Radiologically thicker tumor was predictive of inferior survival.

Observation of a_{0}^{0}(980)-f_{0}(980) Mixing

We report the first observation of a_{0}^{0}(980)-f_{0}(980) mixing in the decays of J/ψ→ϕf_{0}(980)→ϕa_{0}^{0}(980)→ϕηπ^{0} and χ_{c1}→a_{0}^{0}(980)π^{0}→f_{0}(980)π^{0}→π^{+}π^{-}π^{0}, using data samples of 1.31×10^{9}  J/ψ events and 4.48×10^{8}  ψ(3686) events accumulated with the BESIII detector. The signals of f_{0}(980)→a_{0}^{0}(980) and a_{0}^{0}(980)→f_{0}(980) mixing are observed at levels of statistical significance of 7.4σ and 5.5σ, respectively. The corresponding branching fractions and mixing intensities are measured and the constraint regions on the coupling constants, g_{a_{0}K^{+}K^{-}} and g_{f_{0}K^{+}K^{-}}, are estimated. The results improve the understanding of the nature of a_{0}^{0}(980) and f_{0}(980).

Genetic diversity of Jiangsu native chicken breeds assessed with the mitochondrial DNA D-loop region

1. The objective of this study was to determine the origin and evolution of chickens from 5 native breeds that are traditionally raised in Jiangsu Province. 2. To address this question, the complete mitochondrial DNA D-loop sequence of 149 chickens from 5 native breeds of Jiangsu Province was analysed. 3. Sequence read lengths of the native breeds were 1231 to 1232 bp, with a single-base deletion from the 859 bp site in the 1231 bp haplotype. A total of 33 variable sites that defined 19 haplotypes were identified. The average haplotype diversity and nucleotide diversity were 0.862 ± 0.017 and 0.00591 ± 0.00135. 4. Phylogenetic analysis showed that genetic structure of the mtDNA haplotypes of Jiangsu chickens are distributed across 5 clades (haplogroups): Clades A, B, C, D, and E. However, most of the individuals characterised in this study belonged to clades A and B. 5. The results of this study indicate that Jiangsu chicken populations have relatively low nucleotide and haplotype diversity and likely share 5 common maternal lineages.

[Previous medical or surgical abortions and subsequent risk of preterm birth: a birth cohort study]

Objective: To understand the association between medical abortion (MA) or surgical abortion (SA) and the risk of preterm birth (PTB) in subsequent pregnancy. Methods: The prospective cohort study was conducted in Ma'anshan, Anhui province. The information about demographic characteristics and previous MA or SA of 3 474 pregnant women were collected before 14 gestational weeks. Logistic regression analysis was conducted to compare the rates of preterm birth based on the history of previous MA or SA, and 3 256 live births were included in the analysis. Results: The PTB rate and spontaneous preterm birth (sPTB) rate were 4.12% (n=134) and 2.49% (n=81) respectively. Previous MA was associated with an increased risk of total PTB (RR=2.00, 95%CI: 1.04-3.85 for one MA and RR=3.58, 95%CI: 1.04-12.30 for two or more MAs) and sPTB (RR=2.51, 95% CI: 1.23-5.15). The risk of PTB in women with one SA (RR=0.67, 95%CI: 0.42-1.01) or more SA (RR=0.97, 95%CI: 0.51-1.85) did not differ significantly compared with the women with no history of SA. Conclusion: This study suggests that medical abortion could increase the risk of PTB or sPTB.

Selecting stage ypT0-1N0 for locally advanced rectal cancer following preoperative chemoradiotherapy: implications for potential candidates of organ-sparing management

AIM

Local excision or a wait-and-see policy may offer the possibility of organ preservation for locally advanced rectal cancer (LARC) after preoperative chemoradiotherapy (CRT). Identifying associated factors of good responders (GR) with stage ypT0-1N0 would probably influence the selection of potential candidates who were theoretically eligible for organ-sparing management. This study was to establish a scoring system to select stage ypT0-1N0 for LARC following preoperative CRT.

METHOD

Between 2009 and 2014, 262 patients with middle and low LARC were treated with CRT and radical surgery. Clinicopathological data which were found to be significantly associated with GR were incorporated into a scoring system.

RESULTS

Fifty-seven (21.8%) patients were GR with stage ypT0-1N0 in the operative specimen. Multivariate analyses indicated that a low level of pretreatment carcinoembryonic antigen (CEA) and post-treatment CEA <2.55 ng/ml (P = 0.008 and P = 0.009 respectively) and long-axis diameter of residual tumours (P = 0.006) were independently associated with stage ypT0-1N0. The three factors were incorporated into a scoring system. Using receiver operating characteristic curve analysis, we determined a cutoff value of -0.3 for scores, at which the system's sensitivity was 71.9% and specificity 73.1%. When applied to testing samples, the sensitivity was 74.1% and specificity 76.2%.

CONCLUSION

We demonstrated that low levels of pretreatment and post-treatment CEA and the long-axis diameter of residual tumours were associated with stage ypT0-1N0 for LARC after CRT. Therefore, the three-factor scoring system may be used to select potential candidates for organ-sparing management.

MicroRNA-135b inhibits odontoblast-like differentiation of human dental pulp cells by regulating Smad5 and Smad4

AIM

To investigate the function of miRNAs in odontoblast-like differentiation of human dental pulp cells (hDPCs).

METHODOLOGY

Integrated comparative miRNA microarray profiling was used to determine the differential miRNAs expression in odontoblast-like differentiation of hDPCs. The abundance of microRNA-135b (miR-135b) was measured by quantitative real-time reverse transcriptase polymerase chain reaction (qRT-PCR) and in situ hybridization (ISH). Bioinformatic analyses combined with luciferase assays were utilized to identify the targets interacting with miR-135b. Overexpression of miR-135b was performed to investigate the role and mechanism in odontoblast-like differentiation of hDPCs. Statistical analysis was performed by one-way analysis of variance (anova) or Student's t-test.

RESULTS

Thirty-six differentially expressed microRNAs in odontoblast-like differentiation of hDPCs were identified. MiR-135b expression was significantly downregulated during hDPCs differentiation (P < 0.05). In addition, miR-135b was able to bind to the 3'-UTR of the Smad5 and Smad4 and repressed these two genes expression (P < 0.05). Furthermore, overexpression of miR-135b suppressed odontoblast-like differentiation of hDPCs and attenuated the expression of Smad5 and Smad4 (P < 0.05).

CONCLUSIONS

These observations indicated a potential role of miR-135b in mediating odontoblast-like differentiation of hDPCs and inhibition of miR-135b might be a promising therapeutic way to facilitate dentine tissue engineering.

[Intrahepatic cholestasis of pregnancy and fetal outcomes: a prospective birth cohort study]

OBJECTIVE

To evaluate the relations between the second and third trimesters intrahepatic cholestasis of pregnancy (ICP) and the fetal outcomes, in order to provide medical advice for early detection and intervention on ICP.

METHODS

A prospective cohort study was conducted in Ma' anshan, Anhui, China (Ma'anshan Birth Cohort, MABC). Pregnant women within 14 weeks of gestation were consecutively recruited when standards were met. Anthropometrics were collected in early pregnancy. Maternal serum total bile acid level (TBA) was collected in the second and third trimesters, and women were viewed as cases if the results were accorded with clinical diagnosis. Logistic regressions were conducted to examine the associations of the second and third trimester ICP, and fetal outcomes.

RESULTS

A total of 2 978 pregnant women were included in this study. The rate of ICP was 6.5% (n=196), and the rates of the second and third trimesters were 1.4% (n=43) and 5.1% (n=153) respectively. After controlling for potential confounders, we found that ICP from both the second and third trimesters could increase the risks of preterm birth, low birth weight (LBW), fetal distress and meconium-stained amniotic fluid.OR values (95% CI) were 6.42 (2.59-15.93) and 3.73 (2.07-6.72) for preterm birth while 6.52 (2.19-19.45) and 4.90 (2.43-9.90) for LBW, 2.91 (1.27-6.67) and 1.88 (1.11-3.19) for fetal distress and 2.34 (1.19-4.61) and 1.66 (1.11-2.48) for meconium-stained amniotic fluids, respectively. The risk of adverse fetal outcomes caused by the second trimester ICP appeared significantly higher than the third trimester ICP.

CONCLUSION

ICP from the second and third trimesters significantly increased the risk of adverse fetal outcomes, suggesting that clinicians should put more attention to the second trimester ICP. Both early detection and intervention were of great importance in reducing the adverse fetal outcomes.

[Effects of neoadjuvant chemoradiotherapy on the rates of sphincter preserving surgery in lower rectal cancer and analysis of their prognostic factors]

Objectives: To identify independent factors of sphincter preserving surgery, and to evaluated whether preoperative chemoradiotherapy (CRT) improves the sphincter preservation rate for lower rectal cancers. Methods: A total of 541 consecutive patients who underwent curative surgery for locally advanced rectal cancer (cT3-4Nx or cTxN+ ) within 6 cm of the anal verge with or without neoadjuvant CRT in Department of Colorectal Surgery, Union Hospital, Fujian Medical University between September 2000 and September 2013 were reviewed. Of these, 333 patients underwent surgery alone (Non-CRT group) and 208 patients also received preoperative chemoradiotherapy (CRT group). Clinical data were retrospectively reviewed to determine the factors influencing sphincter preservation, and to evaluate sphincter preservation rate according to tumor height over 1-cm intervals. The categorical variables were compared using χ² test and Fisher exact test. Continuous variables were compared using t test. Logistic regression was used to identify factors influencing sphincter preservation. A receiver operating characteristic (ROC) curve was constructed, and Youden's index was calculated to evaluate the predictive abilities of factors. Results: Multivariate analysis indicated that the independent factors influencing sphincter preservation were tumor height (OR=5.867, 95% CI: 4.155 to 8.285, P=0.000), pathological T stage (OR=0.688, 95% CI: 0.462 to 1.025, P=0.066), CRT (OR=2.088, 95% CI: 0.971 to 4.492, P=0.060) and histopathological type (OR=0.288, 95% CI: 0.136 to 0.611, P=0.001). The results of ROC analysis showed that the cut-off points for factors affecting sphincter preservation were as follows: (1) tumor height prior to CRT higher than 4.5 cm, (2) not mucinous or signet ring adenocarcinoma, (3) pathological T stage higher than T3, (4) had received preoperative CRT. In an analysis according to tumor height, the sphincter preservation rate was higher in CRT group only when tumor was located in 3.0 to 3.9 cm and 4.0 to 4.9 cm from the annal verge (3.0 to 3.9 cm, 59.4% vs. 2.8%, χ²=26.138, P=0.000; 4.0 to 4.9 cm, 76.9% vs. 37.9%, χ²=10.563, P=0.001). Conclusions: There is a large increased rate of sphincter preservation when patients meet the following conditions: (1) tumor height prior to CRT higher than 4.5 cm, (2) not mucinous or signet ring adenocarcinoma, (3)pathological T stage higher than T3, (4) had received preoperative CRT. Only when tumors are between 3 and 5 cm from the anal verge, CRT could increase the rate of anal sphincter preservation.

[Prognostic factors of postoperative incisional surgical site infections for colorectal cancer]

Objective: To explore the prognostic factors of postoperative incisional surgical site infections (I-SSI) for colorectal cancer. Methods: Clinical data of 2 385 colorectal cancer patients undergoing resection by the same surgical team in Department of Colon and Rectum Surgery, Fujian Medical University Union Hospital from January 2000 to February 2014 was analyzed retrospectively. There were 1 421 male and 964 female patients, with a mean age of (59±13) years. Univariate analysis and multivariate Logistic regression analysis were performed for independent prognostic factors of I-SSI. Results: The I-SSI occurred in 77 patients (3.23%). The results of univariate analysis showed that there were statistical differences in body mass index (t=-3.356), operation time (t=-3.609), length of incision (t=-5.492), radical operation (χ²=8.963), laparoscopic surgery (χ²=25.884), combined evisceration (χ²=6.349) and intraoperative blood infusion (χ²=4.176) between two groups (all P<0.05) . The results of multivariate Logistic regression analysis showed that independent prognostic factors of I-SSI were identified to be body mass index (OR=1.087, 95%CI: 1.023 to 1.155, P=0.007), operation time (OR=1.007, 95%CI: 1.002 to 1.012, P=0.006), preoperative chemoradiotherapy (OR=2.434, 95%CI: 1.099 to 5.393, P=0.028) and combined evisceration (OR=2.596, 95%CI: 1.060 to 6.357, P=0.037). The independent protective prognostic factor of I-SSI was identified to be the laparoscopic surgery (OR=0.386, 95%CI: 0.170 to 0.877, P=0.023). Conclusions: Body mass index, operation time, preoperative chemoradiotherapy and combined evisceration are identified to be independent prognostic factors for I-SSI. High-risk patients should receive individualized perioperative intervention. Nevertheless, the laparoscopic surgery can decrease the incidence of I-SSI.

Socioeconomic status, human papillomavirus, and overall survival in head and neck squamous cell carcinomas in Toronto, Canada

BACKGROUND

Despite universal healthcare in some countries, lower socioeconomic status (SES) has been associated with worse cancer survival. The influence of SES on head and neck cancer (HNC) survival is of immense interest, since SES is associated with the risk and prognostic factors associated with this disease.

PATIENTS AND METHODS

Newly diagnosed HNC patients from 2003 to 2010 (n=2124) were identified at Toronto's Princess Margaret Cancer Centre. Principal component analysis was used to calculate a composite score using neighbourhood-level SES variables obtained from the 2006 Canada Census. Associations of SES with overall survival were evaluated in HNC subsets and by p16 status (surrogate for human papillomavirus).

RESULTS

SES score was higher for oral cavity (n=423) and p16-positive oropharyngeal cancer (OPC, n=404) patients compared with other disease sites. Lower SES was associated with worse survival [HR 1.14 (1.06-1.22), p=0.0002], larger tumor staging (p<0.001), current smoking (p<0.0001), heavier alcohol consumption (p<0.0001), and greater comorbidity (p<0.0002), but not with treatment regimen (p>0.20). After adjusting for age, sex, and stage, the lowest SES quintile was associated with the worst survival only for OPC patients [HR 1.66 (1.09-2.53), n=832], primarily in the p16-negative subset [HR 1.63 (0.96-2.79)]. The predictive ability of the prognostic models improved when smoking/alcohol was added to the model (c-index 0.71 vs. 0.69), but addition of SES did not (c-index 0.69).

CONCLUSION

SES was associated with survival, but this effect was lost after accounting for other factors (age, sex, TNM stage, smoking/alcohol). Lower SES was associated with greater smoking, alcohol consumption, comorbidity, and stage.

Functional divergence of BAK1 genes from Brassica rapa in regulating plant architecture

BAK1 is a co-receptor of BRI1 in early signaling pathways mediated by brassinosteroids (BRs) and is thought to play a major role in plant growth and development. As the role of BAK1 has not yet been fully elucidated then further research is required to explore its potential for use in genetic modification to improve crops. In this study, three BAK1 genes from the amphidiploid species Brassica rapa were isolated and their kinase functions were predicted following DNA sequence analysis. A bioinformatic analysis revealed that two genes, BrBAK1-1 and BrBAK1-8, shared a conserved kinase domain and 5 tandem leucine-rich repeats (LRRs) that are characteristic of a BAK1 receptor for BR perception, whereas the third gene, BrBAK1-3, was deficient for a signal peptide, but had 4 leucine zippers and 3 leucine-rich repeats (LRRs) in an extracellular domain. All three BrBAK1 kinases localized on the cellular membrane. Ectopic expression of each BrBAK1 gene in BR-insensitive (bri1-5 mutant) Arabidopsis plants indicated that BrBAK1-1 and BrBAK1-8 were functional homologues of AtBAK1 based on the rescue of growth in the bri1-5 mutant. Overexpression of BrBAK1-3 caused a severe dwarf phenotype resembling the phenotype of null BRI1 alleles. The results here suggest there are significant differences among the three BrBAK1 kinases for their effects on plant architecture. This conclusion has important implications for genetic modification of B. rapa.

Multipath correlations in underwater acoustic communication channels

Uncorrelated scattering (US), which assumes that multipath arrivals undergo uncorrelated scattering and are thus uncorrelated, has been the standard model for digital communications including underwater acoustic communications. This paper examines the cross-correlation of multipath arrivals based on at-sea data with different temporal coherence time, assuming quasi-stationary statistics. It is found that multipath arrivals are highly cross-correlated when the channel is temporally coherent, and are uncorrelated when the channel is temporally incoherent. A theoretical model based on the path phase rates and relative-phase fluctuations is used to explain experimentally observed phenomena, assuming the path amplitudes vary slowly compared with the phases. The implications of correlated scattering for underwater acoustic communication channel tracking are discussed.

Transgenic expression of haem oxygenase-1 in pancreatic beta cells protects non-obese mice used as a model of diabetes from autoimmune destruction and prolongs graft survival following islet transplantation

AIMS/HYPOTHESIS

Haem oxygenase 1 (HO-1) has strong anti-apoptotic, anti-inflammatory and antioxidative effects that help protect cells against various forms of immune attack. We investigated whether transgenic expression of Ho-1 (also known as Hmox1) in pancreatic beta cells would protect NOD mice from autoimmune damage and prolong graft survival following islet transplantation.

METHODS

To evaluate the protective effect of beta cell-specific HO-1 in autoimmune diabetes, we used an insulin promoter-driven murine Ho-1 construct (pIns-mHo-1) to generate a transgenic NOD mouse. Transgene expression, insulitis and the incidence of diabetes in mice were characterised. Lymphocyte composition, the development of T helper (Th)1, Th2 and T regulatory (Treg) cells, T cell proliferation and lymphocyte-mediated disease transfer were analysed. The potential effects of transgenic islets and islet transplantation on apoptosis, inflammation and the generation of reactive oxygen species (ROS) and reactive nitrogen species (RNS) were evaluated.

RESULTS

Transgenic mice showed less severe insulitis and a lower incidence of diabetes than non-transgenic control littermates. Lymphocyte composition and functions were not affected. Islets from transgenic mice expressed lower levels of proinflammatory cytokines/chemokines, proapoptotic gene expression and amounts of ROS/RNS, and were more resistant to TNF-α- and IFN-γ-induced apoptosis. Islet grafts from transgenic mice also survived longer in diabetic recipients than control islets.

CONCLUSIONS/INTERPRETATION

Transgenic overexpression of Ho-1 in beta cells protected NOD mice from diabetes and delayed the autoimmune destruction of islet grafts, providing valuable insight into the development of better strategies for clinical islet transplantation in patients with type 1 diabetes.

Structural Analysis of Highly Relaxed GaSb Grown on GaAs Substrates with Periodic Interfacial Array of 90° Misfit Dislocations

We report structural analysis of completely relaxed GaSb epitaxial layers deposited monolithically on GaAs substrates using interfacial misfit (IMF) array growth mode. Unlike the traditional tetragonal distortion approach, strain due to the lattice mismatch is spontaneously relieved at the heterointerface in this growth. The complete and instantaneous strain relief at the GaSb/GaAs interface is achieved by the formation of a two-dimensional Lomer dislocation network comprising of pure-edge (90°) dislocations along both [110] and [1-10]. In the present analysis, structural properties of GaSb deposited using both IMF and non-IMF growths are compared. Moiré fringe patterns along with X-ray diffraction measure the long-range uniformity and strain relaxation of the IMF samples. The proof for the existence of the IMF array and low threading dislocation density is provided with the help of transmission electron micrographs for the GaSb epitaxial layer. Our results indicate that the IMF-grown GaSb is completely (98.5%) relaxed with very low density of threading dislocations (105 cm-2), while GaSb deposited using non-IMF growth is compressively strained and has a higher average density of threading dislocations (>109 cm-2).

Sodium trimer ordering on a NaxCoO2 surface

Sodium ion ordering on an in situ cleaved NaxCoO2 (x=0.84) surface has been studied by ultrahigh vacuum scanning tunneling microscopy at room temperature. Three main phases, with p(3 x 3), ( radical7 x radical7), and (2 radical3 x 2 radical3) hexagonal unit cells and a surface Na concentration of 1/3, 3/7, 1/2, respectively, were identified. One surprising finding is that Na trimers act as the basic building blocks that order in long range. The stability of Na trimers is attributed to the increased Na coordination with oxygen as indicated by ab initio calculations, and possibly at finite temperature by configuration entropy.

A comparison study of cerebral protection using Ginkgo biloba extract and Losartan on stroked rats

It has been well documented that oxidative stress is involved in stroke. Currently, many neuroprotective strategies have been targeted at molecules that are able to act as an oxidant to intervene with free-radical mediated apoptosis in the ischemic penumbra. In particular, natural products which contain antioxidant properties have undoubtedly efficacious for stroke treatment. In the current study, therapeutic effects of Ginkgo biloba extract (EGb) against cerebral protection in Wistar rats underwent middle cerebral artery occlusion (MCAO) was evaluated. A comparison study was conducted by using Losartan, an antihypertensive drug. Gene expression levels of pro-apoptotic genes (AT2 receptor, Fas, Bax and Bcl-xS) have shown to have significant reduction by EGb- and Losartan-treated groups as compared to vehicle group. Significant reduction of immunoreactivity of protein production of these genes, together with least nuclear green fluorescence observed in TUNEL, EGb, as an antioxidant drug, is concluded to have potent and promising therapeutic effect for stroke treatment.

Mixed antagonistic effects of bilobalide at ρ1 GABAC receptor

Bilobalide was found to be a moderately potent antagonist with a weak use-dependent effect at recombinant human rho(1) GABA(C) receptors expressed in Xenopus oocytes using two-electrode voltage clamp methodology. Antagonism of bilobalide at homomeric rho(1) GABA(C) receptors appeared to be mixed. At low concentration, bilobalide (3 microM) caused a parallel right shift and surmountable GABA maximal response of the GABA dose-response curve characteristic of a competitive antagonist. At high concentrations, bilobalide (10-100 microM) caused nonparallel right shifts and reduced maximal GABA responses of GABA dose-response curves characteristic of a noncompetitive antagonist. The potency of bilobalide appears to be dependent on the concentrations of GABA and was more potent at lower GABA concentrations. The mechanism of action of bilobalide at rho(1) GABA(C) receptors appears to be similar to that of the chloride channel blocker picrotoxinin.

Antioxidants in Chinese herbal medicines: a biochemical perspective

Recently, intense interest has focused on the antioxidant properties of natural products. In particular, Chinese herbal medicines (CHM) have become hot topics for life science researchers since many are reported to possess cardioprotective compounds, many of which remain to be identified. Indeed, the exact mechanisms by which CHM work remain unknown. Although many of these herbal remedies are undoubtedly efficacious, few have been scientifically investigated for their active chemical constituents and biological activities. We have previously reported higher activities of antioxidant defence enzymes such as superoxide dismutase, catalase, glutathione peroxidase and glutathione S-transferases in the liver of rats treated with the herb Salvia miltiorrhiza in a model of acute myocardial infarction. Using well established in vitro antioxidant assays employing 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) and diphenyl-l-picrylhydrazyl (DPPH) we have shown that in addition to elevating endogenous antioxidant enzyme activity, Salvia miltiorrhiza and other CHM traditionally used for cardiovascular disorders (such as Rhizoma ligustici, Herba leonuri, Radix achyranthis bidentatae, and Camellia sinensis) contain potent antioxidant moieties in addition to their phenolic constituents. Furthermore, these novel non-phenolic components are effective inhibitors of oxidative reactions mediated by the inflammatory oxidants, peroxynitrite,hypochlorous acid and hydroxyl radical as well as iron-dependent lipid peroxidation. In this review, we discuss the various antioxidant properties of CHM in the context of their biochemical mechanisms.

[Inflammation, bronchial hyperreactivity, and progression of asthma: a 5-year follow-up in grass sensitized farmers]

We studied in a group of 53 asthmatic farmers the influence of various treatment regimens on progression of disease, during five years follow-up. Specific immuno-therapy (SIT) and steroid treated patients showed significantly lower ECP levels and higher methacholine PD20 FEV1 than untreated patients, during all years of the study. During the first two years, spring ECP increase was higher in SIT treated patients than in steroid ones, however no significant differences were found during the following years. Bronchial hyperreactivity showed same course, except for a significant higher PD20 FEV1 in steroid and SIT treated asthmatics, in respect to the steroid or SIT alone. We may conclude that ECP and bronchial reactivity are useful for asthma monitoring and SIT and inhalant steroids have additional effects on asthma.

[Serum tryptase: marker of occupational anaphylaxis]

Tryptase is a protein released by mast cells, which is involved in the enhancement of inflammatory sequences in immune-mediated reactions. According with our experience, some patients having a reaction clinically classified as anaphylaxis, showed high levels of tryptase (> 20 ng/l) but also of serum specific IgE, showing the immune-mediated nature of the reactions. On the other hand workers without specific IgE and with low levels of tryptase probably had developed pseudoallergic (anaphylactoid) reactions. So, tryptase can be used as biomarker of occupational anaphylaxis and appear to be able to make out immune and nonimmune mediated reactions.

beta-Phenylethyl isothiocyanate-mediated apoptosis in hepatoma HepG2 cells

beta-Phenylethyl isothiocyanate (PEITC) is a promising chemoprotective compound that is routinely consumed in the diet as its glucosinolate precursor. Previous studies have shown that PEITC can inhibit phase I enzymes and induce phase II detoxification enzymes along with apoptosis in vitro. The detailed mechanisms involved in the apoptotic cascade, however, have not been elucidated. In the present study, we demonstrate that PEITC can induce apoptosis in hepatoma HepG2 cells in a concentration- and time-dependant manner as determined by TUNEL positive and SubG1 population analysis. Caspase-3-like activity and poly(ADP-ribosyl)polymerase cleavage increased during treatment with 20 microM PEITC; high concentrations, however, induced necrosis. Pre-treatment with Z-VAD-FMK and the caspase-3-specific inhibitor Ac-DEVD-CHO prevented PEITC-induced apoptosis, as determined by caspase-3-like activity and DNA fragmentation. Additional investigations also showed that at concentrations of 5-10 microM PEITC, DNA synthesis was inhibited and G2/M phase cell cycle arrest occurred, correlating with an alteration in cyclin B1 and p34(cdc2) protein levels. Furthermore, we also demonstrate a concentration- and time-dependant burst of superoxide (O2*-) in PEITC-treated cells. However, pre- and co-treatment with the free radical scavengers Trolox, ascorbate, mannitol, uric acid and the superoxide mimetic manganese (III) tetrakis (N-methyl-2-pyridyl) porphyrin failed to prevent PEITC-mediated apoptosis. Taken together, these results suggest that PEITC potently induces apoptosis and cell cycle arrest in HepG2 cells and that the generation of reactive oxygen species appears to be a secondary effect.

Three-dimensional cytomorphology in fine needle aspiration biopsy of medullary thyroid carcinoma

OBJECTIVE

To elucidate three-dimensional (3-D) cytomorphology in fine needle aspiration biopsy (FNAB) of medullary thyroid carcinoma (MTC).

STUDY DESIGN

ENAB was performed on tumors from five patients with MTC. The aspirate was stained and observed under a light microscope (LM). The aspirate was also fixed, dehydrated, critical point dried, spattered with gold ions and observed with a scanning electron microscope (SEM). For transmission electron microscopy (TEM), the specimen was fixed, dehydrated, embedded in an Epon mixture, cut with an ultramicrotome, mounted on copper grids, electron doubly stained with uranium acetate and lead citrate, and observed with TEM. Findings under SEM were correlated with those under LM and TEM.

RESULTS

Under SEM, 3-D cytomorphology of MTC displayed a disorganized cellular arrangement with indistinct cell borders in three cases. The cell surface was uneven and had granular protrusions that corresponded to secretory granules observed under TEM. In one case with multiple endocrine neoplasia type IIB, there were abundant granules on the cell surface. In one case of sporadic MTC with multinucleated tumor giant cells and small cells, granular protrusions also were noted on the cell surface.

CONCLUSION

Granular protrusion was a characteristic finding in FNAB of MTC tinder SEM and might be helpful in the differential diagnosis.

IgG subclass responses in experimental silicosis

Silicosis is a crippling fibrotic lung disease induced by inhaling crystalline silica. In addition to fibrosis, silica inhalation by humans is associated with a number of immunological effects including increased levels of serum immunoglobulins (in particular IgG), increased prevalence of autoantibodies, and autoimmune disease. Recent studies using rodent models have shown that experimental silicosis is associated with a T-helper (TH)1 pattern of T-cell activation in the lungs and lung-associated lymph nodes after silica inhalation, which are also the sites of increased IgG production. We therefore hypothesized that the subclass distribution of IgG production occurring in experimental silicosis would suggest TH1 activation as the primary stimulus for IgG production. Using an ELISPOT assay, we found increased IgG-secreting spot-forming cells of all IgG subclasses in lung-associated lymph nodes taken from silica-exposed rats 3 to 4 months after aerosol exposure to silica. Neither TH1- nor TH2-dependent IgG subclass-secreting cells were selectively enhanced. Our findings suggest that TH1 activation alone does not account for increased production of IgG in experimental silicosis.