[Acidophil stem cell pituitary neuroendocrine tumors/adenoma: a clinicopathological analysis of five cases].

Objective: To investigate the clinicopathological characteristics of acidophil stem cell pituitary neuroendocrine tumors (PitNET)/adenoma. Methods: Five cases of acidophil stem cell PitNET/adenoma were diagnosed between May 2022 and July 2023 at the Second Hospital of Hebei Medical University, Shijiazhuang, China. The clinicopathological features of the tumor were analyzed by using histology, immunohistochemistry, and electron microscopy. The relevant literature was reviewed. Results: There were 1 male and 4 females, aged from 23 to 69 years. Patient 3 was 55 years old at the time of diagnosis and first surgery, and relapsed 5 years later. The patients' median age was 32 years. Patients 1 and 5 showed elevated blood prolactin, with various degrees of hormonal symptoms except Patient 3, who showed only tumor compression symptoms. Imaging studies showed that all cases involved the sellar floor. The tumors of Patients 1, 2 and 5 were closely related to the cavernous sinus segment of the internal carotid artery. The tumors exhibited a diffuse growth pattern with chromophobic to slightly acidophilic cytoplasm. A few of tumor cells showed chromophobic cytoplasm. The nucleoli were conspicuous. Intranuclear inclusion bodies and variably-sized clear vacuoles were observed occasionally. Under electron microscope, marked mitochondrial abnormalities were observed, including increased mitochondria number, expanded hypertrophy, and absence of mitochondrial ridge fracture. Some mitochondrial matrices were dense, while some were vacuolated. Conclusions: Acidophil stem cell PitNET/adenoma is a rare type of pituitary adenomas/PitNETs. It often has a more clinically aggressive manner with immature cells, diffuse expression of PIT1, prolactin, and varying degrees of growth hormone expression. Because of the obvious diversity of their clinical hormone status and hormone immune expression, the diagnosis of this type tumor is still a challenge.

[Association between chronic lung diseases and the risk of lung cancer in UK Biobank: observational and Mendelian randomization analyses].

Objective: To investigate the association between chronic lung diseases and the risk of lung cancer. Methods: Using UK Biobank (UKB) survey data, 472 397 participants who had not previously been diagnosed with cancer and whose self-reported sex was consistent with their genetic sex were studied. Information on the prevalence of previous chronic lung diseases, general demographic characteristics and the prevalence of lung cancer was collected using baseline questionnaires and national health system data. The multivariate Cox proportional risk regression model was used to analyze the association between four previous chronic lung diseases (asthma, chronic obstructive pulmonary disease, idiopathic pulmonary fibrosis and interstitial pulmonary disease) and the risk of lung cancer. A total of 458 526 participants with genotype data in the observational study were selected as research objects, and the closely related and independent genetic loci with four chronic lung diseases were selected as instrumental variables, and the association between four chronic lung diseases and the risk of lung cancer was analyzed by Mendelian randomization (MR). The dose-response relationship between genetic risk score and the risk of lung cancer in different chronic lung diseases was evaluated using a restricted cubic spline function. Results: The age [M (Q1, Q3)] of the subjects was 57 (50, 63) years old, and there were 3 516 new cases of lung cancer (0.74%) during follow-up. The multivariate Cox proportional hazard regression model analysis showed that previous chronic obstructive pulmonary disease and idiopathic pulmonary fibrosis were associated with the risk of lung cancer, about 1.61 (1.49-1.75) and 2.61 (1.24-5.49), respectively. MR Studies showed that genetically predicted chronic obstructive pulmonary disease and idiopathic pulmonary fibrosis were associated with the risk of lung cancer, with HR (95%CI) of 1.10 (1.03-1.19) and 1.04 (1.01-1.08), respectively. The results of restricted cubic spline function analysis showed that the risk of lung cancer increased linearly with the increase of genetic risk scores for chronic obstructive pulmonary disease and idiopathic pulmonary fibrosis (P<0.05). Neither observational studies nor Mendelian randomization analysis found an association between previous asthma or interstitial lung disease and the risk of lung cancer (both P values>0.05). Conclusion: Chronic obstructive pulmonary disease and idiopathic pulmonary fibrosis are potential risk factors for lung cancer.

Characterization of the complete mitochondrial genomes of two Ixodes ticks, I. nipponensis and Ixodes (Pholeoixodes) sp.

In this study, the authors sequenced and characterized the complete mitochondrial (mt) genomes of two hard ticks of the genus Ixodes, I. nipponensis and Ixodes (Pholeoixodes) sp., which were 14 505 and 14 543 bp in length, respectively. Their mt genomes encoded 37 genes, including 13 protein-coding genes (PCGs), 22 transfer RNA genes and two ribosomal RNA genes, and have only one non-coding region. The gene order in their mt genomes was the same as that of other Ixodes spp. mt genomes. The average sequence identity, combined nucleotide diversity, non-synonymous/synonymous substitutions ratio analyses consistently demonstrated that cox1, rrnS, cox2, cox3 and cytb were the most conserved and atp8, nad6 and nad2 were the most variable genes across Ixodes mitogenomes. Phylogeny of the present Ixodes spp., and other selected hard tick species, based on concatenated amino acid sequences of PCGs, confirmed their position within the genus Ixodes and sub-family Ixodinae. The novel mt markers described herein will be useful for further studies of the population genetics, molecular epidemiology and systematics of hard ticks.

MicroRNA-1266 suppresses papillary thyroid carcinoma cell metastasis and growth via targeting FGFR2.

OBJECTIVE: To explore the effects of microRNA-1266 (miR-1266) on metastasis and growth in papillary thyroid carcinoma cells and to provide therapeutic targets for papillary thyroid carcinoma. PATIENTS AND METHODS: By quantitative Real-time polymerase chain reaction (PCR), miR-1266 expression level in 38 pairs of papillary thyroid carcinoma tissues and three breast cancer-derived cell lines was examined. After transfection with miR-1266 mimics, the effects of miR-1266 over-expression on cell proliferation, invasion and migration were analyzed. Further, we employed several databases for the target gene prediction. Dual-luciferase activity assay was performed to verify whether FGFR2 was the direct target gene of miR-1266. Western blotting was conducted to detect protein levels. RESULTS: MiR-1266 was significantly downregulated in papillary thyroid carcinoma tissue samples and cell lines. Over-expression of miR-1266 in papillary thyroid carcinoma cells significantly attenuated the cell proliferation, invasion, and migration. Dual-luciferase report assay and Western blotting confirmed that FGFR2 was a target gene of miR-1266. Furthermore, up-regulation of FGFR2 partially reversed the suppressive effects of miR-1266 over-expression on cell growth and progression. CONCLUSIONS: miR-1266 could inhibit cell proliferation and progression of papillary thyroid carcinoma via targeting FGFR2. Our findings might provide a new target for the diagnosis and treatment of papillary thyroid carcinoma.

Hyperphosphorylation of protein Tau in hippocampus may cause cognitive dysfunction of propofol-anesthetized rats.

OBJECTIVE: We aimed to explore the effect of hyperphosphorylation of Tau on cognitive function of propofol-anesthetized rats. MATERIALS AND METHODS: Thirty 2-month-old male Wistar rats weighing 180-220 g were randomly divided into 3 groups (n=10): group of treating with saline (C group), group of treating with propofol for 1 hour (P1) and 24 h (P24 group). The cognitive function of rats was tested by Morris water maze before and 1 h or 24 h after drug administration. The rats were then sacrificed. The protein and mRNA expression levels of GSK-3ß, total and phosphorylated Tau, cyclin D1, p27kip1 and c-caspase 3 in hippocampus were determined by Western blot and reverse transcriptase-polymerase chain reaction (RT-PCR), respectively. RESULTS: Compared with group C, the incubation period of P1 group and P24 group was prolonged, and the target quadrant retention time was shortened (p<0.05). There was no statistical difference between P1 and P24 group (p>0.05). Immunohistochemistry showed that compared with group C, p-Tau in hippocampus of P1 group and P24 group was highly expressed, with statistical difference (p<0.05). Western blot and RT-PCR showed that protein and mRNA expressions of GSK-3ß, phosphorylated Tau, cyclin D1 and c-caspase 3 in hippocampus of P1 and P24 groups were up-regulated (p<0.05). CONCLUSIONS: Propofol-induced cognitive dysfunction in rats may be related to the hyperphosphorylation of Tau that causes neuronal cells to re-enter the cell cycle, thus leading to apoptosis.

Has-MiR-196a-2 is up-regulated and acts as an independent unfavorable prognostic factor in thyroid carcinoma.

OBJECTIVE: To identify the role of hsa-miR-196a-2 in thyroid cancer by bioinformatics analysis. MATERIALS AND METHODS: The expression profiles of thyroid cancer was download from TCGA. The dysregulated microRNAs were obtained by edger R package. Then, the prognostic data were analyzed by K-M plot. The difference between different groups was analyzed by the t-test. At last, the biological processes of has-miR-196a-2 were obtained with GSEA. RESULTS: In this study, we found that has-miR-196a-2 was upregulated in thyroid carcinoma by analyzing the TCGA database, which was inversely proportional to the prognosis of patients with thyroid carcinoma. Univariate and multivariate COX analysis showed that has-miR-196a-2 was an independent prognostic risk factor for thyroid carcinoma. Higher expressions of has-miR-196a-2 were found in patients with older age, advanced tumor stage, lymph node metastasis, and local infiltration through the t-test. We found that has-miR-196a-2 was enriched in adherent junction, focal adhesion, and actin cytoskeleton, which are closely related to the invasion and migration of the function pathway. Moreover, it is mainly enriched in tumor progression pathways, such as the PPAR pathway and WNT pathway. CONCLUSIONS: Hsa-miR-196a-2 is overexpressed in thyroid tumors and is an independent prognostic risk factor for thyroid carcinoma.

The effect of platelet-rich fibrin on autologous osteochondral transplantation: An in vivo porcine model.

BACKGROUND: This work aimed to evaluate the efficacy of cartilage transplantation to the medial femoral condyle±platelet-rich fibrin (PRF) augmentation in a porcine model. The hypothesis of the study was that PRF may act as a bioactive cell scaffold to fill defects and enhance cartilage regeneration. METHODS: Thirty-two knees of 16 miniature pigs were randomly assigned to four groups. The critical-size osteochondral defects (8x5mm) in femoral condyle of both knees were treated with one of the following: group 1－untreated controls; group 2－cartilage fragments alone; group 3－PRF alone; group 4－PRFT+cartilage fragments. After completion of the surgical implantation, the periosteal patch harvested from the proximal tibia was sutured onto the cartilage of the medial condyle to cover the implanted defects. Animals were sacrificed at six months after treatment. The regenerated cartilages were assessed by gross inspection and histological examination. RESULTS: The best results were obtained with the repair tissue being hyaline-like cartilage (group 4). The grading score of histological evaluation demonstrated that group 4 had better matrix, cell distribution and cartilage mineralization than group 2 and group 3. PRF showed a positive effect on the cartilage repair; the procedure was more effective when PRF was combined with autologous chondrocytes. CONCLUSIONS: This approach may provide a successfully employed technique to target cartilage defects in vivo. Larger groups and longer periods of study may provide more definitive and meaningful support for using this therapeutic approach as a new way of cartilage regeneration.

The affordability for patients of a new universal MDR-TB coverage model in China.

BACKGROUND: China has piloted a new model of universal coverage for multidrug-resistant tuberculosis (MDR-TB), designed to rationalize hospital use of drugs and tests and move away from fee-for-service payment towards a standard package with financial protection against catastrophic health costs. OBJECTIVE: To evaluate the affordability to patients of this new model. DESIGN: This was an observational study of 243 MDR-TB cases eligible for enrolment on treatment under the project. We assessed the affordability of the project from the perspective of households, with a focus on catastrophic costs. RESULTS: Of the 243 eligible cases, 172 (71%) were enrolled on treatment; of the 71 cases not enrolled, 26 (37%) cited economic reasons. The 73 surveyed cases paid an average of RMB 5977 (US$920) out-of-pocket in search costs incurred outside the pilot model. Within the pilot, they paid another RMB 2094 (US$322) in medical fees and RMB 5230 (US$805) in direct non-medical costs. Despite 90% reimbursement of medical fees, 78% of households experienced catastrophic costs, including indirect costs. CONCLUSION: The objectives of the pilot model are aligned with health reform in China and universal health coverage globally. Enrollment would almost certainly be higher with 100% reimbursement of medical fees, but patient enablers will be required to truly eliminate catastrophic costs.

Silencing FKBP38 gene by siRNA induces activation of mTOR signaling in goat fetal fibroblasts.

FKBP38 (also known as FKBP8) is a unique member of the FK506-binding protein (FKBP) family, and its role is controversial because it acts as an upstream regulator of the mTOR signaling pathway, which controls cell growth, proliferation, and differentiation. This study aimed to explore the role of FKBP38 in the activation of mTOR signaling in Cashmere goat (Capra hircus) fetal fibroblasts. To construct a Cashmere goat FKBP38 siRNA eukaryotic expression vector that targets FKBP38 mRNA, we designed shRNA based on the gene sequence deposited in GenBank (accession No. JF714970) and synthesized a DNA fragment encoding the shRNA. The DNA fragment was inserted into the pRNAT-U6.1/Neo vector to construct an expression vector of shRNA, which was labeled pRNAT-FKBP38-shRNA. The recombinant plasmid was used to transfect Cashmere goat fetal fibroblasts (GFb) using lipofectamine™2000. We found that cells were successfully transfected with pRNAT-U6.1/Neo-FKBP38-shRNA. Green fluorescence could be observed in cells following 48-h transfection. Proteins were then isolated from GFbs transfected with pRNAT-FKBP38-shRNA and from control cells, and protein expression was analyzed by western blot. Expression of FKBP38 decreased and mTOR signaling was activated, which induced the phosphorylation of mTOR, S6, and 4EBP1. Thus, FKBP38 gene-silencing activates mTOR signaling in goat cells.

Impact of medical therapy on patients with Crohn's disease requiring surgical resection.

AIM: To evaluate the impact of medical therapy on Crohn's disease patients undergoing their first surgical resection. METHODS: We retrospectively evaluated all patients with Crohn's disease undergoing their first surgical resection between years 1995 to 2000 and 2005 to 2010 at a tertiary academic hospital (St. Paul's Hospital, Vancouver, Canada). Patients were identified from hospital administrative database using the International Classification of Diseases 9 codes. Patients' hospital and available outpatient clinic records were independently reviewed and pertinent data were extracted. We explored relationships among time from disease diagnosis to surgery, patient phenotypes, medication usage, length of small bowel resected, surgical complications, and duration of hospital stay. RESULTS: Total of 199 patients were included; 85 from years 1995 to 2000 (cohort A) and 114 from years 2005 to 2010 (cohort B). Compared to cohort A, cohort B had more patients on immunomodulators (cohort A vs cohort B: 21.4% vs 56.1%, P < 0.0001) and less patients on 5-aminosalysilic acid (53.6% vs 29.8%, P = 0.001). There was a shift from inflammatory to stricturing and penetrating phenotypes (B1/B2/B3 38.8% vs 12.3%, 31.8% vs 45.6%, 29.4% vs 42.1%, P < 0.0001). Both groups had similar median time to surgery. Within cohort B, 38 patients (33.3%) received anti-tumor necrosis factor (TNF) agent. No patient in cohort A was exposed to anti-TNF agent. Compared to patients not on anti-TNF agent, ones exposed were younger at diagnosis (anti-TNF vs without anti-TNF: A1/A2/A3 39.5% vs 11.8%, 50% vs 73.7%, 10.5% vs 14.5%, P = 0.003) and had longer median time to surgery (90 mo vs 48 mo, P = 0.02). Combination therapy further extended median time to surgery. Using time-dependent multivariate Cox proportional hazard model, patients who were treated with anti-TNF agents had a significantly higher risk to surgery (adjusted hazard ratio 3.57, 95%CI: 1.98-6.44, P < 0.0001) compared to those without while controlling for gender, disease phenotype, smoking status, and immunomodulator use. CONCLUSION: Significant changes in patient phenotypes and medication exposures were observed between the two surgical cohorts separated by a decade.

Factors contributing to the efficacy of concurrent-adjuvant chemotherapy for locoregionally advanced nasopharyngeal carcinoma: combined analyses of NPC-9901 and NPC-9902 Trials.

BACKGROUND: The current standard treatment for locoregionally advanced nasopharyngeal carcinoma (NPC) was conventional-fractionation radiotherapy plus concurrent-adjuvant chemotherapy as recommended by the Intergroup-0099 Study. This combined analysis of the NPC-9901 and the NPC-9902 Trials aims to provide more comprehensive data to evaluate the efficacy of the Intergroup-0099 regimen and the contributing factors. METHODS: Eligible patients with stage III-IVB non-keratinizing NPC were randomly assigned to radiotherapy-alone (RT(i) group: 218 patients) or chemoradiotherapy (CRT(i) group: 223 patients) using cisplatin (100mg/m(2)) for three cycles in concurrence with radiotherapy, followed by cisplatin (80 mg/m(2)) plus fluorouracil (1000 mg/m(2)/day for 4 days) for three cycles. The median follow-up was 6.1 years. FINDINGS: Comparison by intention-to-treat showed that the CRT(i) group achieved significant improvement in overall failure-free rate (FFR), locoregional-FFR and cancer-specific survival (p ≤ 0.019); but the improvements for distant-FFR and overall survival (OS) were statistically insignificant (p ≥ 0.14). Further exploratory studies based on actual treatment showed that an additional improvement achieved was a significant gain in OS (CRT(a) versus RT(a) group: 72% versus 63% at 5-year, p=0.037). Multivariate analyses showed that the dose of cisplatin during the concurrent phase had significant impact on locoregional-FFR and OS, while that of fluorouracil during the adjuvant phase was significant for distant-FFR. The 5-year locoregional-FFR for patients who received 0-1, 2 and 3 concurrent cycles were 79%, 88% and 88%, respectively; the corresponding distant-FFR by adjuvant cycles were 68%, 78% and 77%, respectively. INTERPRETATION: Our results support the current practice of adding concurrent cisplatin plus adjuvant cisplatin-fluorouracil to radiotherapy for treating patients with locoregionally advanced NPC. The concurrent phase is important for locoregional control and survival, cisplatin 200mg/m(2) in two concurrent cycles might be adequate. Additional chemotherapy using fluorouracil-containing combination contributed to improving distant control.

50-Hz magnetic field induces EGF-receptor clustering and activates RAS.

PURPOSE: In a previous study, we found that exposure to a 50 Hz magnetic field (MF) could activate stress-activated protein kinase (SAPK) and P38 mitogen-activated protein (MAP) kinase (P38 MAPK) in Chinese hamster lung (CHL) fibroblast cells, and simultaneous exposure to a 'noise' MF of the same intensity inhibited these effects. In order to explore the possible target sites and upstream signal transduction molecules of SAPK and P38 MAPK, and further validate the interference effects of 'noise' MF on 50 Hz MF, the effects of MF exposure on clustering of epidermal growth factor (EGF) receptors and Ras protein activation were investigated. MATERIALS AND METHODS: CHL cells were exposed to a 50 Hz sinusoidal MF at 0.4 mT for different durations, and clustering of EGF receptors on cellular membrane and Ras protein activation were analyzed using immunofluorescence confocal microscopy and co-precipitation technology. EGF treatment served as the positive control. RESULTS: The results showed that, compared with sham-exposed cells, exposure to a 50 Hz MF at 0.4 mT for 5 min slightly induced EGF receptor clustering, whereas exposure for 15 min enhanced receptor clustering significantly. Corresponding to receptor clustering, Ras protein was also activated after exposure to the 50 Hz MF. Exposure to a 'noise' MF (with frequency ranges from 30 - 90 Hz) at the same intensity and durations, did not significantly affect EGF receptor clustering and Ras protein. However, by superimposing the 'noise' MF, receptor clustering and Ras activation induced by 50 Hz MF were inhibited. CONCLUSION: The results suggested that membrane receptors could be one of the most important targets where extremely low frequency (ELF) MF interacts with cells, and Ras may participate in the signal transduction process of 50 Hz MF. Furthermore, a 'noise' MF could inhibit these effects caused by ELF-MF.

Spontaneous formation of highly ordered nanostructures: thermal instability and mode selection in surface-capped polymer films.

We demonstrate a controllable formation process of wave-like patterns in thermally unstable surface-capped polymer films on a rigid substrate. Self-ordered wave-like structures over a large area can be created by applying a small lateral tension to the film, whereupon it becomes unstable. A clear mode selection process which includes creation, decay and interference between coexisting waves at different annealing conditions has been observed, which makes it possible to restrain the patterns which are formed finally. Our results provide a clear and new evidence of spinodal behaviour in such a film due to thermal instability. Furthermore, we show that the well-controlled patterns generated in such a process can be used to fabricate nanostructures for various applications.

Cysts of the tunica albuginea.

The authors report 3 cases of cysts of the tunica albuginea. Scrotal ultrasonography facilitates preoperative diagnosis and helps to avoid orchiectomy or to prevent unnecessary surgery.

Povidone-iodine instillation for management of pelvic lymphocele after pelvic lymphadenectomy for staging prostate cancer.

The development of postoperative lymphoceles following pelvic lymph node dissection is a rare complication. It is a well-described complication of kidney transplantation. A patient who developed a symptomatic pelvic lymphocele after pelvic lymph node dissection for staging prostatic cancer was treated with percutaneous tube drainage, but the treatment was in vain. Successful treatment was accomplished with povidone-iodine instillation into the lymphocele. This simple, safe, and painless method for lymphocele treatment is recommended.

ELF magnetic fields induce internalization of gap junction protein connexin 43 in Chinese hamster lung cells.

We have previously demonstrated that exposure of Chinese hamster lung (CHL) cells to 50 Hz magnetic fields (MFs) and/or 12-O-tetradecanoylphorbol-3-acetate (TPA)-inhibited gap junctional intercellular communication (GJIC). To explore and compare the mechanisms of GJIC inhibition induced by extremely low frequency (ELF) MF and TPA, the number and localization of connexin 43 (C x 43) were studied. The localization of C x 43 was determined with indirect immunofluorescence histochemical analysis and detected by confocal microscopy after exposing CHL cells to 50 Hz sinusoidal magnetic field at 0.8 mT for 24 h without or with TPA (5 ng/ml) for the last 1 h. The C x 43 levels in nuclei and in cytoplasm were examined by Western blotting analysis. The results showed that the cells exposed to MF and/or TPA displayed individual plaques at regions of intercellular contact, which were fewer than the normal cells in number, while the number of C x 43 in cytoplasm increased and congregated near the nuclei. Western blot analysis further demonstrated the quantity of changes in location of Cx43. These results suggest that reduction of C x 43 at regions of intercellular contact may be one of the mechanisms of GJIC inhibition induced by ELF MF.

The effect of T-2 toxin on IL-1beta and IL-6 secretion in human fetal chondrocytes.

The effects of T-2 toxin on IL-1beta and IL-6 secretion in human fetal chondrocytes in vitro were investigated. The evaluation is realised on primary monolayer culture of human fetal epiphyseal chondrocytes with or without PMA stimulation. The levels of supernatant IL-1beta and IL-6 were analyzed by ELISA. As compared with their respective controls, we observed a significant increase of IL-Ibeta and IL-6 in supernatants of chondrocytes cultivated for 24 h with T-2 at 8 ng/ml after PMA stimulation; in the absence of PMA, IL-Ibeta was increased alone after 48 h. The results demonstrated that T-2 toxin could superinduce IL-1beta and IL-6 secretion in chondrocytes. All these data suggested that superinduction of cytokines might be one of the key mechanisms of chondrocyte injuries by T-2 toxin.

Acute hemorrhage in late radiation necrosis of the temporal lobe: report of five cases and review of the literature.

Hemorrhage in late cerebral radiation necrosis is a rare complication after radiotherapy for intracranial and extracranial neoplasms. We report 5 cases of acute hemorrhage in late radiation necrosis of the temporal lobe following radiation therapy for nasopharyngeal carcinoma. In a review of the literature, the authors identified a total of 27 such cases. The interval period between the onset of hemorrhage and cranial irradiation is long (mean = 7.8 years). The most prominent histological feature was the proliferation of large, dilated and thin-walled new blood vessels in a background of gliosis and fibrinoid necrosis of vessels. Rupture of these thin-walled new blood vessels is the proposed mechanism of hemorrhage in this condition.

Brain abscess formation in radiation necrosis of the temporal lobe following radiation therapy for nasopharyngeal carcinoma.

BACKGROUND: Radiation necrosis is a known complication following radiation therapy for extracranial as well as intracranial tumours. However, brain abscess formation in radiation necrosis has not been reported in the literature. We report the clinical data of 6 patients suffering from this condition. METHOD: Twenty-eight patients with radiation necrosis of the temporal lobe following radiotherapy for nasopharyngeal carcinoma were treated surgically at the Department of Neurosurgery, Queen Elizabeth Hospital, Hong Kong between January 1992 and July 1999. Of these, 6 cases were complicated by brain abscess formation. The clinical data of these 6 patients are retrospectively reviewed. FINDINGS: The patients were 5 males and 1 female, ranging in age from 41 to 67 years. Three patients had previous treatment with steroids for the symptomatic radiation necrosis. A history of nasal infection or otitis media was recognised in all 6 patients. All patients were treated surgically by temporal lobectomy and excision of the necrotic tissue together with the abscess cavity. Intra-operatively, a bony defect was observed between the middle cranial fossa and the sphenoid sinus in 3 patients and the bony defect was repaired with a temporalis muscle flap. The species of organisms could only be identified in 3 patients. In 3 patients, the pus smear was positive but the culture was negative. Subsequently, 4 patients recovered and 2 patients died. INTERPRETATION: Cerebral radiation necrosis is a predisposing cause of brain abscess formation. Surgical excision is recommended as the treatment of choice in this group of patients.

Spasmolytic effect of water extract of Stemonae radix on the guinea-pig tracheal smooth muscle in vitro.

The present study examined the relaxing effect of a water extract of Baibu (Stemonae radix, the root tuber of Semona sessilifolia (Miq.) Franch. et Sav.) on carbachol-, histamine- and KCl-induced contractions of the guinea-pig isolated tracheal preparations. The results showed that Baibu (1-50 mg/ml) concentration-dependently relaxed the tracheal preparations contracted by these spasmogens with an IC50 value (mg/ml) of 2.0 +/- 0.1 for carbachol, 41.2 +/- 0.8 for histamine and 18.6 +/- 0.9 for KCl. The effect of Baibu was not affected by the pretreatment with a beta-adrenoceptor antagonist propranolol (10(-6) M), indicating that Baibu's effect was not due to an activation on beta-adrenoceptors. Baibu shifted the concentration-response curve of carbachol to the right in a parallel manner without changing the maximal response, having a pA2 value of 0.16 +/- 0.07 mg/ml (equivalent to a KB = 0.70 +/- 0.11 mg/ml). This indicates a competitive antagonism at the muscarinic receptors. Receptor binding assay indicated that Baibu interacted with the muscarinic receptors (Ki = 0.51 +/- 0.12 mg/ml) and the dihydropyridine (DHP) binding site of L-type Ca2+ channels (Ki = 8.0 +/- 1.9 mg/ml), but not with the histamine H1 receptors. Therefore, the present study demonstrates that Baibu contains the principle(s) acting on the muscarinic receptors and DHP binding sites, which contribute its relaxation effect on the airway smooth muscles.