Hands-on-training tailored in response to pre-questionnaire-based survey on image-guided brachytherapy effectively reduces anxiety about its implementation

This study assessed the significance of hands-on-training (HoT) and questionnaire-based surveys on 3D image-guided brachytherapy (3D-IGBT) and a combination of intracavitary and interstitial brachytherapy, the so-called 'hybrid' BT (HBT), in uterine cervical cancer. In October 2023, 29 radiation oncologists, nurses, radiologic technologists and medical physicists from 10 Japanese facilities participated in an HoT on 3D-IGBT and HBT. Questionnaires were distributed to each participant before and after the HoT, and feedback was obtained through online channels. The questionnaire response rate was 83% (24/29), with at least one participant responding from each facility. 'Insertion of applicators and needles', 'human resource shortage' and 'pain relief and sedation' were the primary concerns of radiation oncologists. 'Applicator reconstruction', ' optimization of dwell positions', ' treatment planning' and ' human resource shortages ' were the primary concerns of radiological technologists and medical physicists. The HoT content was adjusted according to the results of preliminary surveys. The concerns expressed by the participants were addressed during the lectures and practical training. Significant reductions in anxiety were observed toward all items of the 10-point self-assessment after the HoT, regardless of the profession. The average score on satisfaction with the HoT (on a 10-point scale) was 9.52 (minimum of 8 and maximum of 10). In conclusion, HoT tailored in response to a pre-questionnaire-based survey effectively reduced participants' anxiety regarding the implementation of 3D-IGBT and HBT.

Efficacy and safety of FDG-PET for determining target volume during intensity-modulated radiotherapy for head and neck cancer involving the oral level

PURPOSE

To determine the efficacy and safety of target volume determination by 18F-fluorodeoxyglucose positron emission tomography-computed tomography (PET-CT) for intensity-modulated radiation therapy (IMRT) for locally advanced head and neck squamous cell carcinoma (HNSCC) extending into the oral cavity or oropharynx.

METHODS

We prospectively treated 10 consecutive consenting patients with HNSCC using IMRT, with target volumes determined by PET-CT. Gross tumor volume (GTV) and clinical target volume (CTV) at the oral level were determined by two radiation oncologists for CT, magnetic resonance imaging (MRI), and PET-CT. Differences in target volume (GTVPET, GTVCT, GTVMRI, CTVPET, CTVCT, and CTVMRI) for each modality and the interobserver variability of the target volume were evaluated using the Dice similarity coefficient and Hausdorff distance. Clinical outcomes, including acute adverse events (AEs) and local control were evaluated.

RESULTS

The mean GTV was smallest for GTVPET, followed by GTVCT and GTVMRI. There was a significant difference between GTVPET and GTVMRI, but not between the other two groups. The interobserver variability of target volume with PET-CT was significantly less than that with CT or MRI for GTV and tended to be less for CTV, but there was no significant difference in CTV between the modalities. Grade ≤ 3 acute dermatitis, mucositis, and dysphagia occurred in 55%, 88%, and 22% of patients, respectively, but no grade 4 AEs were observed. There was no local recurrence at the oral level after a median follow-up period of 37 months (range, 15-55 months).

CONCLUSIONS

The results suggest that the target volume determined by PET-CT could safely reduce GTV size and interobserver variability in patients with locally advanced HNSCC extending into the oral cavity or oropharynx undergoing IMRT. Trial registration UMIN, UMIN000033007. Registered 16 jun 2018, https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000037631.

Safe dose escalation and reduction of the fraction number of uterine cervical brachytherapy using a gel spacer in the rectovaginal and vesicouterine septum: A planning study

PURPOSE

To evaluate the possibility of dose escalation and reduction of fraction number in cervical brachytherapy using a gel spacer.

MATERIAL AND METHODS

Twenty patients with uterine cervical cancer treated with image-guided adaptive brachytherapy (IGABT) were selected. Hyaluronic acid gel injection (HGI) was performed in the rectovaginal and vesicouterine septum for 10 patients. The other ten patients were not with HGI. Both groups were treated with IGABT involving tandem/ovoid or cylindrical applicators along with additional interstitial needles. Dose distributions approved by radiation oncologists were retrospectively analyzed, and a dose summation of 45 Gy/25 of external beam radiation therapy and IGABT was performed. Dose constraints for D2cc of bladder, rectum, and sigmoid were 80, 70, and 70 Gy, respectively. Equivalent dose in 2-Gy fractions calculations used α/β = 10 Gy for high-risk clinical target volume (CTVHR) D90 and α/β = 3 Gy for organs at risks (OARs). As a planning study, dose distribution rescaling was conducted to deliver as much dose to CTVHR D90 as possible within the dose constraint limitation for OARs when IGABT was performed for four, three, and two fractions in both groups.

RESULTS

The median CTVHR D90 was >80 Gy in the non-HGI group and >85 Gy in the HGI group for virtual two and three fractions. Rectum D2cc was significantly lower in the HGI group for three fractions (p < 0.01).

CONCLUSIONS

In the HGI group, adequate dose delivery to CTVHR could be achieved with a reduced IGABT fraction number while meeting the dose constraints of OARs.

MucoUp® as a spacer in brachytherapy for uterine cervical cancer: A first-in-human experience

We first used MucoUp®, a hyaluronic acid used in endoscopic resection, as a spacer in brachytherapy. In five cervical cancer patients, MucoUp® insertion increased a 90% dose of the high-risk CTV to over 80 Gy while decreasing the dose of organs at risk. No related adverse events were observed.

Palliative Radiotherapy Induced Severe Tumor Lysis Syndrome in a Patient With Multiple Myeloma With Skin Involvement: A Case Report and Review of Literature

BACKGROUND/AIM

Radiotherapy (RT) has been rarely reported as a cause of tumor lysis syndrome (TLS). Therefore, the patient characteristics and details of RT-induced TLS remain unclear, which may delay diagnosis. Herein, we report a case of palliative RT-induced severe TLS in a patient with multiple myeloma (MM) with skin involvement along with literature review.

CASE REPORT

A 75-year-old female with MM was referred to our department in February 2021 because of swelling and pruritus of the bulky tumor on her right breast and severe left leg pain. She had received chemotherapies and autologous peripheral blood stem cell transplantations since October 2012. We administered palliative RT (a single 8 Gy fraction) to the right breast, left tibia, and femur. On day 7 after RT, a shrinkage effect was observed on the right breast lesion, and left leg pain was relieved. Her laboratory results showed hyperuricemia, hyperphosphatemia, and hypercreatininemia. Initially, we considered acute renal failure (ARF) due to MM progression and planned for a follow-up after 1 week. On day 14 after RT completion, she experienced vomiting and anorexia. Her laboratory results became worse. She was admitted with the diagnosis of TLS and received intravenous fluid hydration and allopurinol. Unfortunately, the evolution was marked by severe clinical deterioration with anuria and coma, leading to death on day 35 after RT.

CONCLUSION

It is important to determine whether ARF is due to MM progression or TLS. The occurrence of TLS should be considered in the case of a rapidly shrinking bulky tumor while receiving palliative RT.

Development of deep-inspiration breath-hold system that monitors the position of the chest wall using infrared rangefinder

We conducted a prospective study to quantitatively evaluate the movement of the chest wall to establish the simple and reproducible deep-inspiration breath-hold (DIBH) method. The left nipple position was monitored to confirm the inspiratory state. Planning computed tomography (CT) was performed under DIBH and free-breath. We conducted radiation plans with DIBH and free-breath CT and evaluated organ at risk (OAR) and target doses according to two different plans. The relationship between positioning errors of the chest wall and patient factors was evaluated using univariate analysis and fixed-effects models. Twenty-three patients aged ≤ 60 years were enrolled during January-August 2021; 358 daily radiation treatments were evaluated. The median time of treatment room occupancy was 16 minutes (interquartile range, 14-20). The area of the planning target volume (PTV) surrounded by the 95% isodose line was more extensive in DIBH than in free breathing (71.6% vs 69.5%, P < 0.01), whereas the cardiac and left anterior descending (LAD) artery doses were lower (both P < 0.01). In the fixed-effects model analysis, the occupation time of the treatment room was correlated with positioning error. The difference between the planned and irradiated dose was the largest in the LAD branch of the coronary artery (-2.5 Gy), although the OAR dose decreased owing to positional error. The current DIBH method, wherein a single point on the chest wall is monitored to confirm that the patient is in an inspiratory state, allows radiation to be performed in a short time with a small dose error.

Clinical outcomes of definitive radiotherapy for patients with cT1aN0M0 esophageal cancer unsuitable for endoscopic resection and surgery

Background

Studies on the clinical outcomes of radiotherapy for clinical (c)T1aN0M0 (UICC-TNM Classification, Eighth Edition) esophageal cancer (EC) are limited. Therefore, this retrospective study aimed to clarify the clinical outcomes of definitive radiotherapy (RT) or chemoradiotherapy (CRT) for cT1aN0M0 EC unsuitable for endoscopic resection and surgery.

Methods

Patients with cT1aN0M0 esophageal squamous cell carcinoma who underwent definitive RT or CRT between January 2009 and December 2020 were retrospectively reviewed. The initial response, toxicities, survival rates, recurrence patterns, and salvage treatments of the patients were evaluated. Initial response was measured using the Response Evaluation Criteria in Solid Tumors guideline. Toxicity was assessed and documented following the National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE) version 5.0. Survival rates from the date of initiation of treatment were measured using the Kaplan-Meier method.

Results

Twenty patients treated with definitive RT or CRT were included in the study. The median follow-up duration was 55 months (range, 13-131 months). All patients achieved complete response to the initial treatment. Grade 3 acute toxicities observed esophagitis (10%), pneumonitis (5%), and leukopenia (5%). Late toxicities higher than grade 3 were not observed. The 1-, 3-, and 5-year overall and disease-specific survival rates were 100% and 100%, 83% and 100%, and 67% and 100%, respectively. No treatment-related deaths occurred. Among the 20 patients, 6 showed local recurrence and 2 showed metachronous recurrence. Seven patients underwent salvage endoscopic submucosal dissection (ESD), and one underwent argon plasma coagulation treatment. After the endoscopic treatment, no recurrences were observed.

Conclusions

Definitive RT or CRT was considered an alternative initial treatment for patients with cT1aN0M0 EC who were unsuitable for endoscopic resection and surgery.

Radiologic criteria of retropharyngeal lymph node metastasis in maxillary sinus cancer

Objective

To determine the most appropriate radiologic criteria of metastatic retropharyngeal lymph nodes (RLNs) in patients with maxillary sinus cancer (MSC).

Materials and methods

We retrospectively evaluated 16 consecutive patients who underwent magnetic resonance imaging (MRI) before and after the treatment of locally advanced squamous cell carcinoma of the maxillary sinus. The minimal and maximal diameters of all RLNS were recorded. RLNs were classified as metastatic on the basis of the MRI follow-up (f/u). RLNs were considered non-metastatic if stable disease continued until the final MRI f/u and metastatic in cases with different evaluations (complete response, partial response, progressive disease) determined using Response Evaluation Criteria in Solid Tumours (RECIST) ver. 1.1. The receiver operating characteristic curve (ROC) and area under the curve (AUC) were used to assess the accuracy of various criteria in the diagnosis of metastatic RLNs.

Results

Of the 34 RLNs in 16 cases observed on pretreatment MRI, 7 were classified as metastatic RLNs and 27 as non-metastatic RLNs. Using the radiologic criteria, metastatic RLNs tended to be diagnosed more accurately with the minimal axial diameter than with the maximal axial diameter (AUC; 0.97 vs. 0.73, p = 0.06). The most accurate size criterion of metastatic RLNs was a minimal axial diameter of 5 mm or larger, with an accuracy of 94.1% (32 of 34).

Conclusions

The most appropriate radiologic criterion of metastatic RLNs in MSC is a minimal axial diameter of 5 mm or longer.

Effects of temperature increase during surgical drilling in acrylic resin

BACKGROUND

Acrylic resin is employed for drilling bone biomodels. Since drilling causes temperature rise, the mechanical properties of thermoplastic acrylic resin can be altered, consequently affecting drilling properties. However, it is currently unclear how this temperature increase impacts drilling.

OBJECTIVE

This study reports the effects of temperature rise on both mechanical and drilling properties through experiments in which acrylic resin is drilled under machining conditions employed in surgical operations.

METHODS

Drilling tests were performed using a surgical drill on medical acrylic resin under dry conditions to observe generated cutting chips and measure drilling properties such as torque, drilling time, and temperature rise. Dynamic mechanical analysis measurements were performed to consider temperature effects.

RESULTS

According to the morphological classification of the cutting chips, the drilling process is divided into three phases corresponding with the generation of cylindrical helix, waved, and rounded nubby chips respectively. During drilling, the temperature of the chips can exceed the glass transition temperature (100∘C) resulting in decreased viscoelasticity, which is associated with decreased torque.

CONCLUSIONS

While drilling acrylic resin under surgical machining conditions, increasing temperature can decrease torque and morphologically change cutting chips due to the decrease in mechanical properties above the glass transition temperature.

Interferon-beta induction/interferon-alpha2b plus ribavirin therapy in patients with chronic hepatitis C

Treatment of chronic hepatitis C virus (HCV) infection with interferon (IFN) and ribavirin improves the rate of eradication of the virus by less than 20% in patients with genotype 1b and a high viral load. In this study we assessed whether IFN-beta induction/IFN-alpha2b plus ribavirin enhances the efficacy of the therapy in patients with chronic hepatitis C. The efficacy of IFN-beta induction/IFN-alpha2b plus ribavirin therapy (group A, n=7) was compared with that of IFN-alpha2b plus ribavirin (group B, n=7) in 14 patients with high levels of HCV-RNA (> 100 K/U/ml). No significant differences were observed in the clearance of HCV-RNA between the two groups (A and B, respectively) 2 weeks after the start of the treatment (0% and 14.3%), at the end of the treatment (71.4% and 100%) and 6 months after the end of the treatment (28.6% and 14.3%). Recovery was complete in 28.6% and 14.3%, transient in 42.9% and 85.7% and absent in 28.6% and 0% in groups A and B, respectively. Early log changes in the viral load from the baseline after 2 weeks of treatment were 2.41 +/- 0.91 and 2.77 +/- 0.20 in groups A and B, respectively, with no significant difference between the two groups. In the present study, we were not able to demonstrate that IFN-beta induction/IFN-alpha2b plus ribavirin therapy was superior to IFN-alpha2b plus ribavirin therapy in patients with genotype 1b and high viral loads.

Cloning of peroxisomal ascorbate peroxidase gene from barley and enhanced thermotolerance by overexpressing in Arabidopsis thaliana

A full-length cDNA clone (HvAPX1) encoding a peroxisomal type ascorbate peroxidase was isolated from barley (Hordeum vulgare cv. Haruna-nijyo) leaves by differential display. The deduced amino acid sequence of the HvAPX1 gene had 75.3% homology to that from the Gossypium hirsutum glyoxysomal APX gene and 72.1% homology to that from the Arabidopsis thaliana peroxisomal APX gene, APX3. Southern blot analysis indicated that a single-copy gene in the barley genome encoded HvAPX1. Northern blot analysis showed that the HvAPX1 transcript increased remarkably in response to heat, salt and abscisic acid treatment. Induction was not caused by treatment with hydrogen peroxide. The HvAPX1 gene was introduced into A. thaliana under control of the 35S RNA promoter of the cauliflower mosaic virus. The transgenic plants were significantly more tolerant to heat stress as compared with the wild-type.

Reduction of reaction differences between human mercaptalbumin and human nonmercaptalbumin measured by the bromcresol purple method

Although the bromcresol purple (BCP) method provides high specificity in measurements of serum albumin concentrations, we discovered a reaction difference between the values for human mercaptalbumin (HMA) and human nonmercaptalbumin (HNA) measured by the BCP. We found that the color intensity of HMA with BCP present in the reduced form in the albumin of fresh serum, was lower than for HNA. While maintaining specificity for albumin, we reduced the reaction difference between HMA and HNA, with the addition of sodium dodecylsulfate and 5,5'-dithiobis(2-nitrobenzoic acid) to the BCP reagent. The mean albumin concentration by the BCP procedure for 63 fresh sera and the 63 sera stored for 2 days at room temperature were 35.6 g/L and 38.1 g/L, respectively. Those by the modified BCP procedure were 39.8 g/L and 39.9 g/L, respectively. The difference in measured values between the fresh and stored sera which is believed to be caused by the conversion of HMA to HNA during the storage of sera was not observed in the case of the modified BCP procedure. Our modified BCP method is effective in eliminating uncertainty of the albumin concentration assigned to assay calibrators for the conventional BCP method.

Enhanced expression of a nuclease gene in leaves of barley plants under salt stress

We isolated a cDNA clone, Bnuc1, encoding a nuclease I from leaves of salt-stressed barley (Hordeum vulgare L. cv. Haruna-nijyo) by the differential display method. Northern blot analysis revealed that the transcript of Bnuc1 gene was increased dramatically in barley leaves under salt stress. The expression of Bnuc1 gene was also increased by exogenously applied abscisic acid (ABA) in leaves, but not by gibberellic acid (GA) during seed germination. Furthermore, Bnuc1 gene was expressed more in old leaves than in young leaves during both salt stress and natural senescence. Salt-inducible nuclease activity possibly corresponding to the Bnuc1 gene was detected, and was much higher in old leaves than in young leaves under salt stress.

Expression of a betaine aldehyde dehydrogenase gene in rice, a glycinebetaine nonaccumulator, and possible localization of its protein in peroxisomes

Betaine aldehyde dehydrogenase (BADH) catalyzes the last step in the plant biosynthetic pathway that leads to glycinebetaine. Rice plants (Oryza sativa L.), albeit considered a typical non-glycinebetaine accumulating species, have been found to express this enzyme at low levels. This observation evokes an interest in phylogenic evolution of the enzyme in the plant kingdom. It is reported here that rice plants possess the ability to take up exogenously added betaine aldehyde through the roots and convert it to glycinebetaine, resulting in an enhanced salt-tolerance of the plants. A gene encoding a putative BADH from the rice genome was also cloned and sequenced. The gene was found to contain 14 introns, and the overall nucleotide sequence of the coding region is c. 78% identical to that of the barley BADH cDNA. Cloning of a partial BADH cDNA from rice was accomplished by reverse transcription-polymerase chain reaction (RT-PCR). The nucleotide sequence of the cloned fragment was found to be identical to the corresponding exon regions of the rice genomic BADH gene. The deduced amino acid sequences of rice and barley BADH both contain a C-terminal tripeptide SKL, a signal known to target preproteins to microbodies. This localization was confirmed by an immuno-gold labeling study of transgenic tobacco harboring barley cDNA, which showed BADH protein inside peroxisomes. Northern blot analysis revealed that the level of BADH mRNA is salt-inducible.

Expression of a betaine aldehyde dehydrogenase gene in rice, a glycinebetaine nonaccumulator, and possible localization of its protein in peroxisomes

Betaine aldehyde dehydrogenase (BADH) catalyzes the last step in the plant biosynthetic pathway that leads to glycinebetaine. Rice plants (Oryza sativa L.), albeit considered a typical non-glycinebetaine accumulating species, have been found to express this enzyme at low levels. This observation evokes an interest in phylogenic evolution of the enzyme in the plant kingdom. It is reported here that rice plants possess the ability to take up exogenously added betaine aldehyde through the roots and convert it to glycinebetaine, resulting in an enhanced salt-tolerance of the plants. A gene encoding a putative BADH from the rice genome was also cloned and sequenced. The gene was found to contain 14 introns, and the overall nucleotide sequence of the coding region is c. 78% identical to that of the barley BADH cDNA. Cloning of a partial BADH cDNA from rice was accomplished by reverse transcription-polymerase chain reaction (RT-PCR). The nucleotide sequence of the cloned fragment was found to be identical to the corresponding exon regions of the rice genomic BADH gene. The deduced amino acid sequences of rice and barley BADH both contain a C-terminal tripeptide SKL, a signal known to target preproteins to microbodies. This localization was confirmed by an immuno-gold labeling study of transgenic tobacco harboring barley cDNA, which showed BADH protein inside peroxisomes. Northern blot analysis revealed that the level of BADH mRNA is salt-inducible.

[An autopsy case of neuronal type Charcot-Marie-Tooth disease (HMSN type II) with nerve deafness and psychiatric symptoms]

The clinical and pathological findings of a 41-year-old male patient with atypical Charcot-Marie-Tooth disease were reported. There were 3 cases of subarachnoid haemorrhage, 2 nerve deafness and 2 hereditary motor and sensory neuropathy (HMSN) in his family. He had suffered from progressive nerve deafness since 5 years old and gait disturbance since 37 years old. He had been admitted to the psychiatric hospital 3 times because of hallucinatory-delusional state and behavior abnormalities. Neurological examinations at 39 years old revealed that he had mental deterioration (IQ 66), nerve deafness, diffuse muscle atrophy, most marked distally, sensory disturbance, areflexia, positive Romberg's sign, orthostatic hypotension, dysphagia and slurred speech. MCV of median nerve was 27.8 m/sec, and SCV was not evoked. EEG revealed nonspecific dysfunction of the brain. He died of ileus-like condition at 41 years old. General autopsy showed haemorrhagic infarction of the jejunum and ileum due to compression of the superior mesenteric artery and vein by an adhesion band of connective tissue formed after previous appendectomy. Neuropathological examinations revealed axonal degeneration and loss of myelinated fibers with schwannosis of anterior and posterior spinal nerve roots as well as peripheral nerves. The posterior roots were more severely affected than the anterior ones. Ganglion cells of the posterior root ganglia showed remarkable degeneration and loss. There was severe degeneration of the posterior columns, especially in the gracilis, of the spinal cord. Nerve cells in the anterior horns and Clarke's columns also displayed conspicuous atrophy or central chromatolysis followed by gliosis. There was slight degeneration of the posterior spinocerebellar tracts.(ABSTRACT TRUNCATED AT 250 WORDS)

Irreversible inhibition of thromboxane (TX) A2 synthesis by Y-20811, a selective TX synthetase inhibitor

As Y-20811, sodium (+-)-4-[alpha-hydroxy-5-(1-imidazolyl)-2-methylbenzyl]-3,5-dimethylb+ ++ enzoic acid, has been reported to inhibit serum thromboxane (TX) A2 production with a long duration of action, its mechanism of action was investigated. When [3H]Y-20811 (3 mg/kg) was administered orally to rats, the peak platelet concentration of Y-20811 was obtained 1 hr after the administration, and the T1/2 was 43 hr. The peak plasma concentration of Y-20811 was also obtained 1 hr after administration, but the elimination of Y-20811 from plasma was faster (T1/2 alpha = 1.5 hr, T1/2 beta = 15 hr) than that observed in platelets. Serum TXA2 (estimated as TXB2) production was inhibited significantly from 1 to 72 hr after the oral administration of unlabeled Y-20811 (3 mg/kg), which temporally resembled the change of the platelet Y-20811 concentration. In platelet-rich plasma, [3H]Y-20811 completely inhibited TXA2 production at about 1500 pg/10(9) platelets, and the IC50 level was about 600 pg/10(9) platelets, which was similar to values obtained in ex vivo studies. In addition, inhibition of TXA2 production by Y-20811 still remained after washing the drug-pretreated microsomes, whereas that of dazoxiben completely disappeared. A similar irreversible inhibition of TXA2 production was observed with aspirin. These results suggest that Y-20811 may firmly combine with platelet TX synthetase and may irreversibly inhibit TXA2 production.

Pharmacological actions of Y-24180, a new specific antagonist of platelet activating factor (PAF): II. Interactions with PAF and benzodiazepine receptors

The inhibitory effect of Y-24180, 4-(2-chlorophenyl)-2-[2-(4-isobutylphenyl)ethyl]-6,9-dimethyl-6H-t hieno [3,2-f][1,2,4]triazolo [4,3-a][1,4]diazepine, on platelet activating factor (PAF)-induced platelet aggregation and the specific binding of 3H-PAF to platelets was compared with other thienodiazepine derivatives, WEB 2086 and etizolam. Y-24180 inhibited PAF-induced rabbit platelet aggregation in vitro (IC50 3.84 nM), but had little effect on adenosine diphosphate- or arachidonic acid-induced aggregation. WEB 2086 and etizolam also showed an inhibitory effect of PAF-induced aggregation (IC50 values are 456 and 6730 nM, respectively). In PAF-induced human platelet aggregation, Y-24180 (IC50 0.84 nM) was more potent than WEB 2086 (IC50 4.21 nM) and etizolam (IC50 998 nM). Y-24180, WEB 2086 and etizolam displaced 3H-PAF binding from the washed-platelets of rabbits with an IC50 value of 3.50, 9.35 and 29.5 nM, respectively. In rabbits, pretreatment with Y-24180 and WEB 2086 antagonized PAF-induced platelet aggregation dose-dependently. The significant inhibitory effect of Y-24180 (1 mg/kg, p.o.) lasted 72 hr after a single dose oral administration. WEB 2086 (10 mg/kg, p.o.) also antagonized the ex vivo response induced by PAF 1 hr after administration, but no significant effect was observed 3 hr after administration. Y-24180 displaced 3H-diazepam binding from the synaptosomal membranes of rat cerebral cortex with a Ki value of 3.68 microM. The affinity of Y-24180 for benzodiazepine(BZP) receptors was lower than those of WEB 2086 and etizolam and was about 1000 times lower than that for PAF receptors in platelets.

Protective effect of Y-20811, a long-lasting thromboxane synthetase inhibitor, on endotoxin shock in rabbits

The effect of sodium 4-[alpha-hydroxy-5-(imidazolyl)-2-methylbenzyl]-3,5-dimethyl benzoate dihydrate (Y-20811), a selective thromboxane (TX) synthetase inhibitor, on endotoxin shock was investigated in comparison with aspirin. The drugs were orally administered to rabbits at 24 and 1 hour before injection of endotoxin (5 mg/kg, i.v.). Y-20811 (1 mg/kg) promoted the recovery of decreased platelet counts, and inhibited hypotension induced by endotoxin. It also inhibited the increase in plasma TXB2 and 6-keto PGF1 alpha. Aspirin at 30 mg/kg, inhibited hypotension and the increase in both plasma TXB2 and 6-keto PGF1 alpha levels, but it failed to inhibit the decrease in platelet counts. In the control group, all rabbits died within 180 min after endotoxin injection, while Y-20811 completely protected animals against death at a dose of 0.3 mg/kg. Aspirin also protected animals against death at a dose of 30 mg/kg, which was, however, about one hundredth potent of Y-20811. These results indicate that Y-20811 is useful in treating endotoxin shock.

An antagonistic activity of etizolam on platelet-activating factor (PAF). In vitro effects on platelet aggregation and PAF receptor binding

The antagonistic effect of etizolam, an anti-anxiety drug, on platelet-activating factor (PAF) was investigated in rabbit platelets in vitro. Etizolam inhibited PAF-induced aggregation in a dose-dependent manner, with an IC50 of 3.8 microM, about one tenth that of triazolam (IC50 = 30 microM). At 300 microM, it inhibited both ADP and arachidonic acid-induced aggregation only slightly, while the other anti-anxiety drugs tested had no effect on PAF-induced aggregation even at this concentration. Etizolam and triazolam inhibited the specific binding of 3H-PAF to PAF receptor sites on washed rabbit platelets with IC50 values of 22 nM and 320 nM, respectively. Diazepam and estazolam were inactive even at 1 microM. These results indicate that etizolam is a specific antagonist of PAF.

[Benign clear cell tumor of the lung--a study of immunohistochemistry]

A case of benign clear cell tumor of the lung was investigated immunohistochemically and histochemically. The tumor cells showed a packed proliferation pattern composed of two cell types. The one had polygonal, abundant eosinophilic cytoplasm, and the other had clear cytoplasm. These cells contained glycogen in the cytoplasm, detected by PAS and diastase treatment. Immunohistochemically, the tumor was strongly and diffusely stained by anti-vimentin antibody. And anti-NSE and S-100 protein antibodies were also positive in part. But anit keratin, Factor VIII, desmin, myoglobin and myosin antibodies were entirely negative. These results suggest that this tumor is a special neoplasia originating from neural tissue.

Effects of Y-20811, a long-lasting thromboxane synthetase inhibitor, on thromboxane production and platelet function

Effects of a new imidazole derivative, sodium 4-[alpha-hydroxy-5-(imidazolyl)-2-methylbenzyl]-3,5-dimethyl benzoate dihydrate (Y-20811), on thromboxane (TX) production and platelet aggregation were investigated. Y-20811 inhibited TX synthetase (IC50 = 2.2 X 10(-8) M) and platelet aggregation induced by arachidonic acid (AA) in human, guinea pig and rabbit platelets in vitro. Administered orally to rabbits, Y-20811 at a dose of 1 mg/kg decreased serum TXB2 concomitant with increasing 6-keto PGF1 alpha and at a dose of 3 mg/kg inhibited AA-induced platelet aggregation, in both cases for at least 48 hours. Y-20811 (0.3 mg/kg/day) administered to rabbits for 7 days decreased serum TXB2 levels by 50-90% during the medication, and these levels were restored to initial values 3 days after withdrawal of the drug. At a dose of 1 mg/kg Y-20811 protected rabbits against death induced by AA (2 mg/kg). These results indicate that Y-20811 is a selective and long-lasting TX synthetase inhibitor and an anti-aggregating agent useful in preventing thrombotic disorders.

Juvenile secretory carcinoma and juvenile papillomatosis

Two cases of juvenile secretory carcinoma associated with juvenile papillomatosis are reported. One patient's disease was initially diagnosed at the age of 13 and she died 12 years later with extensive metastases. The contralateral breast at autopsy showed findings indicative of juvenile papillomatosis. The second case is that of an 18-year-old girl who had multiple juvenile secretory carcinomas in the left breast associated with juvenile papillomatosis.

Purification of a calmodulin-binding protein from chicken gizzard that interacts with F-actin

A calmodulin-binding protein called "caldesmon" was purified from chicken gizzard muscle as the major calmodulin-binding protein in this tissue. Its molecular weight estimated by sodium dodecyl sulfate/polyacrylamide gel electrophoresis was 150,000, and two of these polypeptides constituted the native molecule. Caldesmon is an actin-binding protein also, binding F-actin reversibly in the presence or absence of Ca2+. The interaction of caldesmon with F-actin was abolished by the binding of calmodulin with the caldesmon. Because the interaction between caldesmon and calmodulin was Ca2+-dependent but the interaction between caldesmon and F-actin was not, Ca2+ acts as a flip-flop switch between the formations of two complexes, caldesmon.calmodulin and caldesmon.F-actin: increasing the formation of the former complex at increased Ca2+ level and the formation of the latter complex at decreased Ca2+ level. The equilibrium of the formations of both complexes was achieved at a Ca2+ concentration near 1 microM.