Laparoscopic repair for internal hernia associated with colostomy: a case report

A 63-year-old woman was admitted with abdominal pain two months after laparoscopic abdominoperineal resection for rectal cancer. Computed tomography revealed dilated small intestine had passed through a defect between the lifted sigmoid colon and abdominal wall. She was diagnosed with small bowel obstruction without strangulation due to internal hernia and managed nonoperatively based on her wish. Recurrence of intestinal obstruction occurred for which curative surgery was performed laparoscopically. The herniated intestine was restored to the normal position, and the hernia orifice was closed using barbed suture, on laparoscopic management. Internal hernia is a rare complication after colostomy that requires surgical management. Although laparoscopic approach on re-operation is difficult, laparoscopic surgery may be suitable for patients with IHAC in terms of required less use of adhesiolysis.

Impact of Inferior Mesenteric Artery Occlusion on the Calibre of Collateral Arteries of the Colon

BACKGROUND/AIM

The inferior mesenteric arteries (IMA) are occluded in some colorectal cancer patients. This study evaluated the impact of IMA occlusion on the calibre of collateral arteries.

PATIENTS AND METHODS

As an IMA obstruction model, 20 patients who underwent abdominal aortic aneurysm surgery, with ligated, excluded, or embolised IMA, were enrolled. Changes in the calibre of the left colic arteries (LCAs) and marginal arteries after surgeries were evaluated.

RESULTS

The cross-sectional area of the LCA significantly increased after surgery (4.34 mm² vs. 6.34 mm², p=0.0009) and that of the marginal artery did not change significantly (2.69 mm² vs. 3.01 mm², p=0.33).

CONCLUSION

The calibre of the LCA increased after IMA occlusion. The descending branch of the LCA should be confirmed preoperatively to preserve blood flow during a low tie procedure.

Optimal Size Criteria for Lateral Lymph Node Dissection After Neoadjuvant Chemoradiotherapy for Rectal Cancer

BACKGROUND

Although chemoradiotherapy followed by radical surgery without lateral lymph node dissection is the current standard treatment in patients with rectal cancer, recent studies have demonstrated the benefits of adding lateral lymph node dissection to total mesorectal excision in patients with suspected lateral lymph node metastasis. However, the optimal indication for lateral lymph node dissection after chemoradiotherapy has not been determined.

OBJECTIVE

This study aimed to establish the optimal indication for lateral lymph node dissection after chemoradiotherapy in patients with rectal cancer.

DESIGN

This is a retrospective study.

SETTINGS

This study was conducted at a single referral hospital.

PATIENTS

A total of 279 patients with rectal cancer who underwent chemoradiotherapy followed by radical surgery between 2007 and 2018 were retrospectively enrolled.

MAIN OUTCOME MEASURES

The largest lateral lymph nodes on CT were retrospectively assessed and compared with the pathologic results of dissected lateral lymph nodes and recurrences in lateral lymph node areas.

RESULTS

The incidence of lateral lymph node metastasis after chemoradiotherapy was estimated to be 9.3%. Although patients with lateral lymph node metastasis frequently developed distant recurrence, 40.4% survived for >5 years without recurrence. An analysis of the lateral lymph node sizes showed that lateral lymph node size ≥8 mm before chemoradiotherapy was the optimal criterion for lateral lymph node dissection, with a sensitivity and specificity of 92.3% and 78.7%. Using this criterion, 72.0% of the patients could be spared lateral lymph node dissection.

LIMITATIONS

Because of the retrospective nature of the present study, the selection of patients who underwent lateral lymph node dissection was biased.

CONCLUSIONS

The optimal indication for lateral lymph node dissection was lateral lymph node size ≥8 mm before chemoradiotherapy. Cancer could be eradicated in >30% of patients with lateral lymph node metastasis by dissecting metastatic lateral lymph nodes. See Video Abstract at http://links.lww.com/DCR/B428.

CRITERIOS DE TAMAO PTIMO PARA LA DISECCIN DE GANGLIOS LINFTICOS LATERALES DESPUS DE LA QUIMIORRADIOTERAPIA NEOADYUVANTE PARA EL CNCER DE RECTO

ANTECEDENTES:Aunque la quimiorradioterapia seguida por cirugía radical sin disección de ganglios linfáticos laterales es el tratamiento estándar actual en pacientes con cáncer de recto, estudios recientes han demostrado beneficios de agregar disección de ganglios linfáticos laterales a la escisión mesorrectal total en pacientes con sospecha de metástasis de ganglios linfáticos laterales. Sin embargo, no se ha determinado la indicación óptima para la disección de los ganglios linfáticos laterales después de la quimiorradioterapia.OBJETIVO:Este estudio tuvo como objetivo establecer la indicación óptima para la disección de los ganglios linfáticos laterales después de la quimiorradioterapia en pacientes con cáncer de recto.DISEÑO:Estudio retrospectivo.ENTORNO CLINICO:Este estudio se realizó en un solo hospital de referencia.PACIENTES:Se inscribieron retrospectivamente un total de 279 pacientes con cáncer de recto que se sometieron a quimiorradioterapia seguida por cirugía radical entre 2007 y 2018.PRINCIPALES MEDIDAS DE VALORACION:Los ganglios linfáticos laterales más grandes en la tomografía computarizada se evaluaron retrospectivamente y se compararon con los resultados patológicos de los ganglios linfáticos laterales disecados y recidivas en las áreas de los ganglios linfáticos laterales.RESULTADOS:Se estimó que la incidencia de metástasis en los ganglios linfáticos laterales después de la quimiorradioterapia fue del 9,3%. Aunque los pacientes con metástasis en los ganglios linfáticos laterales con frecuencia desarrollaron recurrencia a distancia, el 40,4% sobrevivió durante más de 5 años sin recurrencia. Un análisis de los tamaños de los ganglios linfáticos laterales mostró que la mayor dimensión de los ganglios linfáticos laterales ≥ 8 mm antes de la quimiorradioterapia eran el criterio óptimo para la disección de los ganglios linfáticos laterales, con una sensibilidad y especificidad del 92,3% y 78,7%, respectivamente. Utilizando este criterio, el 72,0% de los pacientes podría evitarse la disección de los ganglios linfáticos laterales.LIMITACIONES:Debido a la naturaleza retrospectiva del presente estudio, la selección de pacientes que fueron sometidos a disección de ganglios linfáticos laterales fue sesgada.CONCLUSIÓN:La indicación óptima para la disección de los ganglios linfáticos laterales fue la dimensión mayor de los ganglios linfáticos laterales ≥ 8 mm antes de la quimiorradioterapia. El cáncer se podría erradicar en más del 30% de los pacientes con metástasis en los ganglios linfáticos laterales disecando los ganglios linfáticos laterales metastásicos. Consulte Video Resumen en http://links.lww.com/DCR/B428.

Epithelial-mesenchymal transition and metastatic ability of CD133+ colorectal cancer stem-like cells under hypoxia

Although CD133 is a representative cancer stem cell marker, its function in tumor aggressiveness under hypoxia remains unclear. Therefore, the present study aimed to investigate the associations between CD133, the epithelial-mesenchymal transition and distant metastasis in colorectal cancer. CD133⁺ and CD133⁻ cells were isolated from a single colorectal cancer cell line LoVo, and their adhesive and migratory properties were compared under hypoxic conditions. Immunostaining analysis was performed to determine CD133 expression in clinical samples of primary tumors, as well as liver and peritoneal metastases. Under hypoxia, the expression levels of hypoxia-inducible factor (HIF)-1α and the epithelial-mesenchymal transition markers N-cadherin and vimentin were significantly higher in the CD133⁺ compared with those in the CD133⁻ cells. Furthermore, the migratory ability of the CD133⁺ cells was higher compared with that of the CD133⁻ cells under hypoxia. By contrast, the expression levels of β1 integrin were significantly lower in the CD133⁺ cells under hypoxia compared with those in the CD133⁻ cells. Immunohistochemical analysis of clinical samples revealed that the levels of CD133 expression in metastatic tissues from the liver were significantly higher compared with those in the corresponding primary tumors, whereas CD133 expression levels in peritoneal metastatic tissues were significantly lower compared with those in the corresponding primary tumors. In conclusion, compared with the CD133⁻ cells, the CD133⁺ colorectal cancer cells exhibited enhanced levels of HIF-1α expression and tumor cell migration during hypoxia. This was associated with an increased ability of epithelial-mesenchymal transition, possibly leading to the acquisition of an increased hematogenous metastatic potential and eventually resulting in liver metastasis. High β1 integrin expression levels in the CD133⁻ cells under hypoxia may serve a key role in cell adhesion to the peritoneum, resulting in peritoneal metastasis.

Risk factors and therapeutic significance of inguinal lymph node metastasis in advanced lower rectal cancer

PURPOSE

This study aimed to clarify predictors and therapeutic significance of inguinal lymph node metastasis (ILNM) in patients with rectal cancer.

METHODS

Patients with rectal adenocarcinoma invading the anal canal who underwent curative surgery between 2003 and 2019 were retrospectively reviewed. Synchronous and metachronous lymph node (LN) metastasis were collectively defined as final nodal metastasis (f-LNM). Factors associated with f-LNM were analyzed. Moreover, the "modified therapeutic value index," defined by multiplication of the frequency of f-LNM by the 5-year overall survival rate for patients who received treatment for f-LNM, was calculated for each LN area.

RESULTS

A total of 145 patients were enrolled (16 patients with f-ILNM). To predict f-ILNM, the cutoff of the inguinal lymph node (ILN) diameter of 8.5 mm gave an area under the curve of 0.889. Dentate line involvement (odds ratio 33.4) and ILN larger than the cutoff of 8 mm (odds ratio 11.9) were independently associated with f-ILNM. The modified therapeutic value indices of the inguinal, lateral pelvic, and mesorectal LNs in the entire population were 6.1, 8.2, and 20.3 points, respectively. In patients with dentate line invasion by cancer, the index of the ILN increased to 11.7 points. In patients with an ILN > 8 mm, the index further increased to 21.1 points.

CONCLUSION

Dentate line involvement and ILN > 8 mm predicted the development of ILNM in patients with rectal cancer invading the anal canal. Treatment of the ILN should be considered for patients with the above predictors given the significant therapeutic outcomes.

Metastatic role of mammalian target of rapamycin signaling activation by chemoradiotherapy in advanced rectal cancer

Postoperative distant metastasis dramatically affects rectal cancer patients who have undergone neoadjuvant chemoradiotherapy (NACRT). Here, we clarified the association between NACRT‐mediated mammalian target of rapamycin (mTOR) signaling pathway activation and rectal cancer metastatic potential. We performed immunohistochemistry for phosphorylated mTOR (p‐mTOR) and phosphorylated S6 (p‐S6) on surgical specimen blocks from 98 rectal cancer patients after NACRT (cohort 1) and 80 colorectal cancer patients without NACRT (cohort 2). In addition, we investigated the association between mTOR pathway activity, affected by irradiation, and the migration ability of colorectal cancer cells in vitro. Based on the results of the clinical study, p‐mTOR was significantly overexpressed in cohort 1 (with NACRT) as compared to levels in cohort 2 (without NACRT) (P < .001). High p‐mTOR and p‐S6 levels correlated with the development of distant metastasis only in cohort 1. Specifically, high p‐S6 expression (HR 4.51, P = .002) and high pathological T‐stage (HR 3.73, P = .020) after NACRT were independent predictors of the development of distant metastasis. In vitro, p‐S6 levels and migration ability increased after irradiation in SW480 cells (TP53 mutation‐type) but decreased in LoVo cells (TP53 wild‐type), suggesting that irradiation modulates mTOR signaling and migration through cell type‐dependent mechanisms. We next assessed the expression level of p53 by immunostaining in cohort 1 and demonstrated that p‐S6 was overexpressed in samples with high p53 expression as compared to levels in samples with low p53 expression (P = .008). In conclusion, p‐S6 levels after NACRT correlate with postoperative distant metastasis in rectal cancer patients, suggesting that chemoradiotherapy might modulate the mTOR signaling pathway, promoting metastasis.

Risk factors and therapeutic significance for inguinal lymph node metastasis in advanced lower rectal cancer

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Background: Which patients with lower rectal cancer are at risk of inguinal lymph node metastasis (ILNM) and how to treat ILNM remain unclear. This study aimed to clarify the predictors of ILNM and clinical significance of treatment for ILNM. Methods: Consecutive patients with rectal adenocarcinoma invading the anal canal who underwent curative surgery between 2003 and 2019 at a single institution were retrospectively reviewed. The pathological nodal involvement in mesorectal, lateral pelvic or inguinal lymph nodes (ILN) at the time of rectal surgery and of later onset were collectively defined as final nodal metastasis (f-LNM) in this study. Factors associated with f-LNM were analyzed. Moreover, the ‘modified therapeutic value index’ defined by the 5-year overall survival rate of patients treated against f-LNM multiplied by their frequency was calculated for each lymph node area. Results: A total of 145 patients were enrolled, among whom16 patients developed ILNM. For predicting f-ILNM, the cutoff 8.5 mm of ILN diameter gave area under the curve of 0.889. Dentate line involvement and ILN larger than a simplified cutoff of 8 mm were independently associated with the development of ILNM (odds ratio: 33.4 and 11.9, respectively). The modified therapeutic value indice of inguinal, lateral pelvic and mesorectal LNs in the entire population were 6.1, 8.2 and 20.3 points, respectively. In patients with dentate line invaded by cancer, they were 11.7, 5.8 and 16.2 points, respectively. Moreover, the index of ILN was 21.1 points when confined to patients with ILN larger than 8 mm. Conclusions: Dentate line involvement and ILN larger than 8 mm were predictive of developing ILNM in patients with rectal cancer invading the anal canal. Treatment of ILNM may be recommended for patients manifesting the above predictors, given the significant therapeutic outcomes.

The combination of temsirolimus and chloroquine increases radiosensitivity in colorectal cancer cells

The PI3K/AKT/mTOR pathway and autophagy are known to play important roles in cancer radioresistance. The aim of the present study was to investigate whether the combination of temsirolimus (TEM), an mTOR inhibitor, and chloroquine (CQ), an autophagy inhibitor, can increase radiosensitivity in colorectal cancer (CRC) cells. The efficacies of TEM and/or CQ as radiosensitizers were examined using clonogenic assays in CRC cell lines SW480 and HT‑29. The expression levels of the phosphorylated isoforms of S6 and 4E‑BP1, downstream proteins of mTOR, as well as the expression levels of p62 and LC3, autophagy‑related proteins, were assessed by western blot analysis. The formation of acidic organelles was detected in acridine orange‑stained cells. Apoptosis and caspase activity were assessed using flow cytometry. The results revealed that ionizing radiation (IR) activated the downstream proteins of mTOR and induced autophagy. In the clonogenic assays, neither TEM nor CQ influenced the efficacy of IR, whereas their combination significantly increased the dose‑dependent efficacy of IR. TEM inhibited phosphorylation of the downstream proteins of mTOR and induced autophagy. CQ inhibited autophagy in the late phase and did not influence the downstream proteins of mTOR. TEM and CQ inhibited both the phosphorylation of downstream proteins of mTOR and autophagy. Cell death analysis revealed that the combination of TEM and CQ strongly induced apoptosis in cells exposed to IR. In conclusion, the combination of TEM and CQ increased radiosensitivity in CRC cells through co‑inhibition of mTOR and autophagy.

Correlations between the Recurrence Patterns and Sizes of Lateral Pelvic Lymph Nodes before and after Chemoradiotherapy in Patients with Lower Rectal Cancer

OBJECTIVE

Factors that predict rectal cancer metastasis to the lungs remain undefined. We investigated whether the lateral pelvic lymph node (LPN) sizes before and after chemoradiotherapy (CRT) correlate with lung metastasis after surgery for lower rectal cancer.

METHODS

Two hundred and forty patients with lower rectal cancer who received preoperative CRT and curative surgery between 2003 and 2017 were examined. Computed tomography-measured LPN sizes before and after CRT were retrospectively determined by 1 colorectal surgeon who was blinded to the patients' clinical and pathological outcomes.

RESULTS

The 5-year cumulative lung metastasis rates were 15.2%. The mean LPN sizes in patients who developed lung metastasis were larger than those in patients who did not (pre-CRT: 8.7 vs. 6.3 mm, p = 0.003; post-CRT: 6.8 vs. 4.5 mm, p = 0.001). The cumulative lung metastasis rate in patients with large LPNs was higher than in those with small LPNs both before and after CRT. On multivariate analysis, lung metastasis was independently correlated with the LPN size only after CRT (hazard ratio [HR]: 5.58), together with the ypT stage (HR: 2.96) and the tumor location (HR: 0.38).

CONCLUSIONS

LPN size after CRT is strongly predictive of postoperative lung metastasis in patients with lower rectal cancer.

Perforation of jejunal diverticulum with ectopic pancreas

Perforation of jejunal diverticulum is a rare complication. Here, we report a case of jejunal diverticulum penetration with surrounding ectopic pancreas. An 83-year-old female patient was admitted to our department with acute onset of severe abdominal pain lasting for half a day. Abdominal computed tomography showed outpouching of the small intestine that contained air/fluid, with multiple surrounding air bubbles in the mesentery of the small intestine. She was diagnosed with penetration of the small intestine, and an emergency laparotomy was indicated. The penetrated jejunal diverticulum was identified ~20-cm distal to the ligament of Treitz. Partial resection of the jejunum was performed, and her postoperative course was uneventful. The pathological findings confirmed diverticulum penetration into the mesentery and severe inflammation at the site, with surrounding ectopic pancreas. Furthermore, the pancreatic ducts were opened through the penetrated diverticulum. This rare case shows that the ectopic pancreas might have caused penetration of jejunal diverticulum owing to the pancreatic duct opening through the diverticulum.

Development of a membrane dialysis bioreactor and its application to a large-scale culture of a symbiotic bacterium, Symbiobacterium thermophilum

A simple membrane dialysis bioreactor was developed for a large-scale axenic culture of Symbiobacterium thermophilum, a symbiotic thermophile that requires co-cultivation with an associating thermophilic Bacillus strain S for normal growth. The bioreactor consisted of an outer- and an inner-coaxial cylindrical compartment bordered across a dialyzing membrane, which enabled a 1 l-scale dialysis culture with exchange of low molecular metabolites between the two compartments to be performed. Using the bioreactor, growth characteristics of S. thermophilum and Bacillus strain S were assessed under two medium conditions. The growth of S. thermophilum was measured by quantitative PCR because the bacterium formed no visible colonies and gave abnormally low turbidity. In medium containing 2% tryptone peptone, S. thermophilum proliferated up to 4x10(7) cells/ml, and strict dependence on the co-culture with Bacillus strain S was observed. On the other hand, medium containing 0.5% yeast extract not only facilitated the growth of S. thermophilum in the co-culture (6x10(7) cells/ml), but also allowed limited pure growth independent of Bacillus strain S (1x10(7) cells/ml), implying that some component of yeast extract can partially replace the growth requirement of S. thermophilum supplied by Bacillus strain S. Both the oxidative redox potential values and the cell morphology in the independently growing culture suggested the occurrence of marked unbalanced growth possibly caused by significant metabolic changes. The bioreactor is applicable to the analyses of culturing characteristics in symbiotic systems between free-living microorganisms.

Acceleration of lung metastasis by up-regulation of CD44 expression in osteosarcoma-derived cell transplanted mice

The effect of CD44-phenotypic expression on metastasis to the lung was studied using a spontaneous murine osteosarcoma-derived cell line, POS-1, stimulated with lipopolysaccharide (LPS). POS-1 cells were inoculated into the hind paws of 20 C3H/HeJ mice and produced a visible mass in all mice in 5 weeks, and these transplanted tumors resulted in lung metastasis in all mice. The number of metastatic foci in the lungs was 12.0+/-2.1 (mean+/-SD) with LPS-stimulated cells, which was significantly higher than that of unstimulated cells (5.8+/-1.4; N=10 for each; P<0.05). Hyaluronate (HA), a ligand of CD44, inhibited a number of lung metastases in a dose-dependent manner (0.5% HA, 3.0+/-1.1; 0.005% HA, 5.1+/-1.5; without HA, 8.6+/-1.7; N=10 for each; P<0.05, each group with HA versus the group without HA). Adhesion assay by coculturing POS-1 cells and lung microvascular endothelial cells on culture plate showed that the adhesion was significantly lower in HA treated POS-1 than those without HA (1.18+/-0.12 and 2.74+/-0.17, respectively, P<0.05). These results suggest that lung metastasis was accelerated by up-regulation of CD44.

Role of asymmetric signals in left-right patterning in the mouse

Left-right asymmetric signaling molecules in mammals include three transforming growth factor beta (TGFbeta)-related factors, Nodal, Lefty1 and Lefty2. They are all expressed on the left half of developing mouse embryos. Nodal acts as a left-side determinant by transducing signals through Smad and FAST and by inducing Pitx2 expression on the left side. Lefty proteins are antagonists that inhibit Nodal signaling. There are positive and negative transcriptional regulatory loops between nodal and lefty2 genes. Thus, Nodal activates its own gene and lefty2. Lefty2 protein produced then inhibits Nodal signaling and terminates expression of both genes. This feedback mechanism can restrict the range and duration of Nodal signaling in developing embryos.

The transcription factor FoxH1 (FAST) mediates Nodal signaling during anterior-posterior patterning and node formation in the mouse

FoxH1 (FAST) is a transcription factor that mediates signaling by transforming growth factor-beta, Activin, and Nodal. The role of FoxH1 in development has now been investigated by the generation and analysis of FoxH1-deficient (FoxH1(-/-)) mice. The FoxH1(-/-) embryos showed various patterning defects that recapitulate most of the defects induced by the loss of Nodal signaling. A substantial proportion of FoxH1(-/-) embryos failed to orient the anterior-posterior (A-P) axis correctly, as do mice lacking Cripto, a coreceptor for Nodal. In less severely affected FoxH1(-/-) embryos, A-P polarity was established, but the primitive streak failed to elongate, resulting in the lack of a definitive node and its derivatives. Heterozygosity for nodal renders the FoxH1(-/-) phenotype more severe, indicative of a genetic interaction between FoxH1 and nodal. The expression of FoxH1 in the primitive endoderm rescued the A-P patterning defects, but not the midline defects, of FoxH1(-/-) mice. These results indicate that a Nodal-FoxH1 signaling pathway plays a central role in A-P patterning and node formation in the mouse.

The retinoic acid-inactivating enzyme CYP26 is essential for establishing an uneven distribution of retinoic acid along the anterio-posterior axis within the mouse embryo

Retinoic acid (RA), a derivative of vitamin A, plays a pivotal role in vertebrate development. The level of RA may be determined by the balance between its synthesis and degradation. We have examined the role of CYP26, a P450 enzyme that may degrade RA, by generating mutant mice that lack CYP26. CYP26(-/-) mice exhibited anomalies, including caudal agenesis, similar to those induced by administration of excess RA. The concentration of endogenous RA, as revealed by marker gene activity, was markedly increased in the tailbud of the mutant animals, in which CYP26 is normally expressed. Expression of T (Brachyury) and Wnt3a in the tailbud was down-regulated in CYP26(-/-) mice, which may underlie the caudal truncation. The lack of CYP26 also resulted in homeotic transformation of vertebrae as well as in misspecification of the rostral hindbrain associated with anterior expansion of RA-positive domains. These results suggest that local degradation of RA by CYP26 is required for establishing an uneven distribution of RA along the anterio-posterior axis, which is essential for patterning the hindbrain, vertebrae, and tailbud.

Two-step regulation of left-right asymmetric expression of Pitx2: initiation by nodal signaling and maintenance by Nkx2

Pitx2 is left--right (L--R) asymmetrically expressed initially in the lateral plate and later in primordial visceral organs. The transcriptional regulatory mechanisms that underlie L--R asymmetric expression of Pitx2 were investigated. Mouse Pitx2 has a left side-specific enhancer (ASE) that mediates both the initiation and maintenance of L--R asymmetric expression. This element contains three binding sites for the transcription factor FAST. The FAST binding sites function as Nodal-responsive elements and are sufficient for the initiation but not for the maintenance of asymmetric expression. The maintenance requires an Nkx2-5 binding site also present within the ASE. These results suggest that the left-sided expression of Pitx2 is directly initiated by Nodal signaling and is subsequently maintained by Nkx2. Such two-step control may represent a general mechanism for gene regulation during development.

Coordination control of intramolecular electron transfer in boronate-bridged zinc porphyrin-diimide molecules

Three sets of dyads, in which a zinc-porphyrin (ZP) electron donor is connected to an aromatic diimide electron acceptor,either pyromellitimide (PI) or naphthalene-1,8:4,5-tetracarboxylic acid diimide (NI), via a boronate-ester bridge, a piperidine bridge, and a 1,3-dioxolane bridge, respectively, were prepared for the purpose of control of intramolecular electron transfer (ET) by acid-base reactions at the connecting bridge. Boronate-ester bridge is a Lewis acidic site and confers a chance to regulate intramolecular ET reaction upon base coordination. This has been demonstrated by suppression of photoinduced ET from ZP to PI or NI in highly electron-pair donating solvents or upon addition of a fluoride anion. To extend this strategy to control of ET-path selectivity, we prepared triad 18, which consists of a ZP donor bearing NI and PI acceptors at similar distances through a boronate-ester bridge and an acetal bridge, respectively. Photoexcitation of 18 in a free form led to intramolecular ET from (1)()ZP preferentially to NI, but the ET path was completely switched toward PI in F(-)-coordinated form without a serious drop in the rate, constituting a novel ET-switching molecular system.

Symbiobacterium thermophilum gen. nov., sp. nov., a symbiotic thermophile that depends on co-culture with a Bacillus strain for growth

A Gram-negative and tryptophanase-positive thermophile, whose growth is dependent on co-culture with an associating Bacillus strain, had been reported and tentatively named Symbiobacterium thermophilum strain T(T). Axenic culture of strain T(T) was recently established by dialysing cultures with the supporting bacterial strains or adding their culture broth. Phylogenetic analysis of strain T(T), based on the 16S rDNA sequence, was conducted for the validation of S. thermophilum. The sequence of strain T(T) was located at the outermost position in the high-G+C Gram-positive group distinctly isolated from any other branches hitherto known. Ten sequences identical to that of strain T(T), and one sequence closely related to it, were identified for the first time from soil and compost samples. The outer membrane of strain T(T) had a three-layered structure, outside the cytoplasmic membrane, which is similar to the S-layer in the cells of members of the Bacillaceae. Chemical analysis of the cells revealed that menaquinone-6 is a major component of the quinone system. According to these results, along with several previous observations (i.e. a G+C DNA content of 65 mol% and the identification of iso-C15:0 and iso-C17:0 acids as major cellular fatty acids), the new taxon Symbiobacterium thermophilum gen. nov., sp. nov. is proposed. The type strain is S. thermophilum strain T(T) (= IAM 14863T).

[Anesthetic management of a patient with diffuse pulmonary hamartoangiomyomatosis associated with spontaneous pneumothorax]

We reported successful anesthetic management of a 34 year-old woman with diffuse pulmonary hamartoangiomyomatosis associated with spontaneous pneumothorax. She had recurrent pneumothorax and chest X-ray film showed reticulo-granular shadow, and chest CT revealed multiple bullae. Induced by thiopental and succinylcholine, anesthesia was maintained safely with enflurane in oxygen. Nitrous oxide was used after thoracotomy. This disease accompanies multiple bullae in the lung and some patients have complications such as tuberous sclerosis or hemangioma of the kidney. Therefore, we have to pay attention to both bullae and other complications.

Systolic time intervals and impedance cardiogram in pregnant and toxemic women

STI measurements and impedance cardiography were carried out during gestation and post partum in 231 cases. In normal pregnant women, prolongation of the Q-I interval, isometric contraction time (ICT), preejection period (PEP) and shortening both of the Q-II interval and ejection time (ET) were all marked in late stages of pregnancy. Mean values for stroke volume (SV), cardiac output (CO) and cardiac index (CI) were at the maximum at 16-23 weeks of pregnancy, and then fell in the antepartum period. The total peripheral resistance (TPR) at 16-23 weeks of pregnancy was lower than in other periods. In the postpartum period, the heart rate was lowered, and the Q-II interval and ICT were prolonged. In toxemic pregnancy, SV, CO and CI were lower than those of the normal group and various changes in STI were more apparent than those of non-toxemic pregnants in the supine position. By the postural change from supine to left lateral in toxemia, the improvement in STI was not as good as in the normal pregnant group and, moreover, SV and CO were decreased and TPR was increased. These results suggest that in toxemic pregnancy the left ventricle might be less complaint and less sensitive to the increase in venous return.