X-ray structure of a novel endolysin encoded by episomal phage phiSM101 of Clostridium perfringens.

Gram-positive bacteria possess a thick cell wall composed of a mesh polymer of peptidoglycans, which provides physical protection. Endolysins encoded by phages infecting bacteria can hydrolyse peptidoglycans in the bacterial cell wall, killing the host bacteria immediately. The endolysin (Psm) encoded by episomal phage phiSM101 of enterotoxigenic Clostridium perfringens type A strain SM101 exhibits potent lytic activity towards most strains of Clostridium perfringens. Psm has an N-terminal catalytic domain highly homologous to N-acetylmuramidases belonging to the glycoside hydrolase 25 family, and C-terminal tandem repeated bacterial Src homology 3 (SH3_3) domains as the cell wall-binding domain. The X-ray structure of full-length Psm and a catalytic domain of Psm in complex with N-acetylglucosamine were determined to elucidate the catalytic reaction and cell wall recognition mechanisms of Psm. The results showed that Psm may have adopted a neighbouring-group mechanism for the catalytic hydrolysing reaction in which the N-acetyl carbonyl group of the substrate was involved in the formation of an oxazolinium ion intermediate. Based on structural comparisons with other endolysins and a modelling study, we proposed that tandem repeated SH3_3 domains of Psm recognized the peptide side-chains of peptidoglycans to assist the catalytic domain hydrolysing the glycan backbone.

Full mini nutritional assessment and prognosis in elderly patients with pulmonary tuberculosis.

OBJECTIVE: Malnutrition is observed frequently in elderly patients with pulmonary tuberculosis (TB). Full Mini Nutritional Assessment (full MNA) is a useful method of measuring nutrition status for elderly person. The objective of this study is to examine the relationship between full MNA and the mortality of elderly patients with pulmonary TB. METHODS: We evaluated 53 elderly patients with pulmonary TB. The nutrition risk assessment was carried out using full MNA. RESULTS: A receiver operating characteristic (ROC) curve was generated for further analysis of the prognostic value of full MNA score. The area under the curve was 0.856 (95% confidence interval [CI], 0.751-0.961). We used the maximum Youden index to obtain optimal cutoff values for full MNA score for prognostic assessment in elderly patients with pulmonary TB. For predicting the risk of mortality, the optimal cutoff value for full MNA score was 13.75. Based on this cutoff value, the Cox proportional hazard model was applied to assess the ability of full MNA score < 14 to predict the prognosis of elderly patients with pulmonary TB. Multivariate analysis identified age (hazard ratio [HR] = 1.114, 95% CI, 1.018-1.219, p = 0.019) and full MNA score < 14 (HR = 9.038, 95% CI, 1.064-76.768, p = 0.044) to be significant independent prognostic factors for survival. CONCLUSION: Severe malnutrition, as defined by full MNA score < 14, was a predictor of high mortality.

The prognostic significance of nutritional status using malnutrition universal screening tool in patients with pulmonary tuberculosis.

BACKGROUND: Malnutrition is frequently observed in patients with pulmonary tuberculosis (TB). The present study aimed to examine the relationship between nutritional status using Malnutrition Universal Screening Tool (MUST) and the mortality of patients with pulmonary TB. METHODS: Fifty-seven patients with pulmonary TB were analyzed. Nutrition assessment was carried out using MUST. The Cox proportional hazard model was applied to assess the ability of MUST to predict prognosis. Receiver operating characteristic curve analysis was used to assess MUST score as a prognostic indicator in pulmonary TB patients. To obtain optimal cut-off values for MUST score for prognostic assessment in TB patients, we used the maximum Youden Index. RESULTS: For predicting the risk of mortality, the optimal cut-off value for MUST score was 3.5. Univariate and multivariate analyses identified age and MUST score ≥ 4 as significant independent prognostic factors for survival. The patients with MUST score ≤ 3 had a median survival of 481 days (95% CI: 453 to 510) and that for the patients with MUST score ≥ 4 was 304 days (95% CI: 214 to 394); the difference was statistically significant (P = 0.001). CONCLUSION: MUST appears to be a reliable tool for nutritional risk assessment of patients with pulmonary TB. In addition, MUST may be a useful prognostic indicator of survival in patients with pulmonary TB.

Bis(triethoxysilyl)ethane (BTESE)-Organosilica Membranes for H2O/DMF Separation in Reverse Osmosis (RO): Evaluation and Correlation of Subnanopores via Nanopermporometry (NPP), Modified Gas Translation (mGT) and RO Performance.

A 40 cm length Bis(triethoxysilyl)ethane (BTESE) membrane having different pore sizes was successfully prepared by changing the number of coating times for gas permeation (GP) and organic solvent reverse osmosis (OSRO) separation study. It was found that BTESE-6 membranes prepared through six-time coating consisted of small-sized pores in the range 0.56 to 0.64 nm estimated using modified Gas Translation (mGT) method and 0.59 to 0.67 nm estimated by nanopermporometry (NPP) method, respectively. These membranes demonstrated a high DMF rejection, RDMF > 95% with total flux, Jv total > 5 kg m-2 h-1 at operating condition feed pressure, Pf: 8 MPa; feed temperature, Tf : 50 °C; and feed flowrate, Qf : 30 mL/min; and they exhibited a high degree selectivity of He/SF6 in the range of ~ 260-3400 at a permeation temperature 200 °C. On the other hand, the larger pore sizes of the BTESE-4 membranes (pore size estimates > 0.76 nm to 1.02 nm) exhibited low DMF rejection and a low degree selectivity of He/SF6 around ~30% and 25, respectively, at the same operating condition as BTESE-6. Both GT and NPP methods can be considered as an indicator of the measurement membrane pore size. From this study, it was found that He and SF6 gases can be some of the potential predictors for water and DMF permeance. Furthermore, by comparing our OSRO membrane with other PV membranes for DMF/H2O separation, our BTESE-6 membranes still exhibited high flux in the range of 3-6 kg m-2 h-1 with a separation factor H2O/DMF in the range of 80-120.

Treatment for chemotherapy-induced alopecia in mice using parathyroid hormone agonists and antagonists linked to a collagen binding domain.

Parathyroid hormone (PTH) agonists and antagonists have been shown to improve hair growth after chemotherapy; however, rapid clearance and systemic side-effects complicate their usage. To facilitate delivery and retention to skin, we fused PTH agonists and antagonists to the collagen binding domain (CBD) of Clostridium histolyticum collagenase. in-vitro studies showed that the agonist fusion protein, PTH-CBD, bound collagen and activated the PTH/parathyroid hormone-related peptide receptor in SaOS-2 cells. The antagonist fusion proteins, PTH(7-33)-CBD and PTH([-1]-33)-CBD, also bound collagen and antagonized PTH(1-34) effect in SaOS-2 cells; however, PTH(7-33)-CBD had lower intrinsic activity. Distribution studies confirmed uptake of PTH-CBD to the skin at 1 and 12 hr after subcutaneous injection. We assessed in vivo efficacy of PTH-CBD and PTH(7-33)-CBD in C57BL/6J mice. Animals were depilated to synchronize the hair follicles; treated on Day 7 with agonist, antagonist, or vehicle; treated on Day 9 with cyclophosphamide (150 mg/kg i.p.) or vehicle; and sacrificed on Day 39. Normal mice (no chemo and no treatment) showed rapid regrowth of hair and normal histology. Chemo+Vehicle mice showed reduced hair regrowth and decreased pigmentation; histology revealed reduced number and dystrophic anagen/catagen follicles. Chemo+Antagonist mice were grossly and histologically indistinguishable from Chemo+Vehicle mice. Chemo+Agonist mice showed more rapid regrowth and repigmentation of hair; histologically, there was a normal number of hair follicles, most of which were in the anagen phase. Overall, the agonist PTH-CBD had prominent effects in reducing chemotherapy-induced damage of hair follicles and may show promise as a therapy for chemotherapy-induced alopecia.

A single injection of the anabolic bone agent, parathyroid hormone-collagen binding domain (PTH-CBD), results in sustained increases in bone mineral density for up to 12 months in normal female mice.

Parathyroid hormone (PTH) is the most effective osteoporosis treatment, but it is only effective if administered by daily injections. We fused PTH(1-33) to a collagen binding domain (PTH-CBD) to extend its activity, and have shown an anabolic bone effect with monthly dosing. We tested the duration of action of this compound with different routes of administration. Normal young C57BL/6J mice received a single intraperitoneal injection of PTH-CBD (320 µg/kg). PTH-CBD treated mice showed a 22.2 % increase in bone mineral density (BMD) at 6 months and 12.8 % increase at 12 months. When administered by subcutaneous injection, PTH-CBD again caused increases in BMD, 15.2 % at 6 months and 14.3 % at 12 months. Radiolabeled PTH-CBD was concentrated in bone and skin after either route of administration. We further investigated skin effects of PTH-CBD, and histological analysis revealed an apparent increase in anagen VI hair follicles. A single dose of PTH-CBD caused sustained increases in BMD by >10 % for 1 year in normal mice, regardless of the route of administration, thus showing promise as a potential osteoporosis therapy.

Development and characterization of a xylose-inducible gene expression system for Clostridium perfringens.

A xylose-inducible gene expression vector for Clostridium perfringens was developed. Plasmid pXCH contains a chromosomal region from Clostridium difficile (xylR-P(xy)(lB)): xylR, encoding the xylose repressor, xylO, the xyl operator sequence, and P(xylB), the divergent promoter upstream of xylBA encoding xylulo kinase and xylose isomerase. pXCH allows tightly regulated expression of the chloramphenicol acetyltransferase reporter and the α-toxin genes in response to the inducer concentration. Thus, pXCH could constitute a new valuable genetic tool for study of C. perfringens.

Development and application of a method for counterselectable in-frame deletion in Clostridium perfringens.

Many pathogenic clostridial species produce toxins and enzymes. To facilitate genome-wide identification of virulence factors and biotechnological application of their useful products, we have developed a markerless in-frame deletion method for Clostridium perfringens which allows efficient counterselection and multiple-gene disruption. The system comprises a galKT gene disruptant and a suicide galK plasmid into which two fragments of a target gene for in-frame deletion are cloned. The system was shown to be accurate and simple by using it to disrupt the alpha-toxin gene of the organism. It was also used to construct of two different virulence-attenuated strains, ΗΝ1303 and HN1314: the former is a disruptant of the virRS operon, which regulates the expression of virulence factors, and the latter is a disruptant of the six genes encoding the α, θ, and κ toxins; a clostripain-like protease; a 190-kDa secretory protein; and a putative cell wall lytic endopeptidase. Comparison of the two disruptants in terms of growth ability and the background levels of secreted proteins showed that HN1314 is more useful than ΗΝ1303 as a host for the large-scale production of recombinant proteins.

High-level production and purification of clostripain expressed in a virulence-attenuated strain of Clostridium perfringens.

Clostripain (CLO) produced by Clostridium histolyticum is an arginine-specific endopeptidase with the potential for applicability to diverse medical and industrial uses. In this study, we developed an expression system allowing high-level production and efficient purification of recombinant CLO (rCLO). Our expression system comprises pCLO, an rCLO expressing vector, and Clostridium perfringens 13Δ6, an in-frame deletion strain as to six genes encoding major virulence factors and secretory proteins. rCLO was purified from the culture supernatant of C. perfringens 13Δ6/pCLO by ammonium sulfate precipitation, hydroxyapatite chromatography, and affinity chromatography on benzamidine-Sepharose. From 200 ml of culture supernatant 4.5 mg of purified rCLO was obtained. N-Terminal amino acid sequencing and molecular mass determination of the purified rCLO and commercially available CLO revealed that the two enzymes have identical subunits, a 38.1-kDa heavy chain and a 15.0-kDa light chain, indicating that rCLO is processed in the same manner as CLO. Analysis of the enzymatic activities toward N-benzoyl-L-arginine p-nitroanilide and acyl-L-lysine p-nitroanilide showed that rCLO and CLO exhibit strict specificity for arginine at the P1 position, and that the specific activity of the former is approximately 2-fold higher than that of the latter. These results indicate that the new method involving a virulence-attenuated C. perfringens strain is useful for preparing large amounts of high-grade rCLO.

Identification and characterization of a putative endolysin encoded by episomal phage phiSM101 of Clostridium perfringens.

Clostridium perfringens produces potent toxins and histolytic enzymes, causing various diseases including life-threatening fulminant diseases in humans and other animals. Aiming at utilizing a phage endolysin as a therapeutic alternative to antibiotics, we surveyed the genome and bacteriophage sequences of C. perfringens. A phiSM101 muramidase gene (psm) revealed by this study can be assumed to encode an N-acetylmuramidase, since the N-terminal catalytic domain deduced from the gene shows high homology of those of N-acetylmuramidases. The psm gene is characteristic in that it is present in phiSM101, an episomal phage of enterotoxigenic C. perfringens type A strain, SM101, and also in that homologous genes are present in the genomes of all five C. perfringens toxin types. The psm gene was cloned and expressed in Escherichia coli as a protein histidine-tagged at the N-terminus (Psm-his). Psm-his was purified to homogeneity by nickel-charged immobilized metal affinity chromatography and anion-exchange chromatography. The purified enzyme lysed cells of all C. perfringens toxin types but not other clostridial species tested, as was shown by a turbidity reduction assay. These results indicate the Psm-his is useful as a cell-wall lytic enzyme and also suggest that it is potentially useful for biocontrol of this organism.

Purification and characterization of a clostripain-like protease from a recombinant Clostridium perfringens culture.

Clostridium perfringens produces a homologue of clostripain (Clo), the arginine-specific endopeptidase of Clostridium histolyticum. To determine the biochemical and biological properties of the C. perfringens homologue (Clp), it was purified from the culture supernatant of a recombinant C. perfringens strain by cation-exchange chromatography and ultrafiltration. Analysis by SDS-PAGE, N-terminal amino acid sequencing and TOF mass spectrometry revealed that Clp consists of two polypeptides comprising heavy (38 kDa) and light (16 kDa or 15 kDa) chains, and that the two light chains differ in the N-terminal cleavage site. This difference in the light chain did not affect the enzymic activity toward N-benzoyl-l-arginine p-nitroanilide (Bz-l-arginine pNA), as demonstrated by assaying culture supernatants differing in the relative ratio of the two light chains. Although the purified Clp preferentially degraded Bz-dl-arginine pNA rather than Bz-dl-lysine pNA, it degraded the latter more efficiently than did Clo. Clp showed 2.3-fold higher caseinolytic activity than Clo, as expected from the difference in substrate specificity. Clp caused an increase in vascular permeability when injected intradermally into mice, implying a possible role of Clp in the pathogenesis of clostridial myonecrosis.

High-level expression of his-tagged clostridial collagenase in Clostridium perfringens.

Clostridium histolyticum collagenase is used to isolate cells from various organs and tissues for tissue engineering, and also to treat destructive fibrosis; thus, the demand for high-grade enzyme preparations is increasing. In this study, we constructed a plasmid encoding C. histolyticum type II collagenase (ColH) with a C-terminal hexahistidine tag (ColH-his) to facilitate the purification of the enzyme through immobilized metal affinity chromatography (IMAC). When ColH-his was expressed in a protease-deficient mutant of Clostridium perfringens, it was produced in the culture supernatant more efficiently than the untagged ColH. ColH-his exhibited the same hydrolytic activity as ColH against 4-phenylazobenzyloxy-carbonyl-Pro-Leu-Gly-Pro-D-Arg (Pz peptide), a synthetic collagenase substrate. From 100 ml of the culture supernatant, approximately 1 mg of ColH-his was purified by ammonium sulfate precipitation, IMAC, and high-performance liquid chromatography on a MonoQ column. When IMAC was performed on chelating Sepharose charged with Zn(2+) instead of Ni(2+), a potential carcinogenic metal, the specific activities against Pz peptide and type I collagen decreased slightly. However, they were comparable to those reported for other recombinant ColHs and a commercial C. histolyticum collagenase preparation, suggesting that this expression system is useful for large-scale preparation of high-grade clostridial collagenases.

[Expression of mesothelin as a potential diagnostic marker in mesothelioma].

Histological discrimination of mesothelioma from adenocarcinoma is often difficult, therefore, many investigators have tried immunohistochemical, ultrastructual, and molecular methods. Economically, immunohistological studies are more excellent, compared with ultrastractual and molecular biological methods. Immunohistologically, many well known markers are divided into two category; adenocarcinoma-related markers, which expressed by adenocarcinoma, and mesothelioma-related makers, which are positive for mesothelioma. CEA, TTF-1, and Ber-Ep4 are well known adenocarcinoma-related markers, mesothelin, TM, HBME-1 and calretinin, have been used as mesothelioma-related markers. Most previous reports associated with discrimination of adenocarcinoma and mesothelioma mentioned that a diagnosis of epithelioid mesothelioma would be excluded by the presence of adenocarcinoma-related antibody. The positive ratio of mesothelioma-related antibodies is lower than that of adenocarcinoma-related antibodies. Only a single mesothelioma-related marker cannot lead to a diagnosis of epithelioid mesothelioma and a correct diagnosis can be made by combination of several makers, which contain both mesothelioma-related markers and adenocarcinoma-related markers. We immunohistologically examined 41 cases of mesothelioma and 16 cases of adenocarcinoma of the lung, and re-evaluated the use of immunohistochemical markers, compared with previous reports. Reactivity for mesothelin was obtained in 19 (73%) of the epithelioid mesotheliomas, but none (0%) of the lung adenocarcinomas. None of the sarcomatoid mesotheliomas exhibited positivity for this marker, nor was any reactivity seen in the spindle cell component of the biphasic mesotheliomas. These findings indicate that, in some instances, mesothelin immunostaining can assist in the diagnosis of mesothelioma.

[A case of primary lung cancer with cervical tuberculous lymphadenitis].

A 66-year-old woman was admitted due to right cervical lymphadenopathy and an abnormal chest radiograph. Acid-fast bacilli smear of fine needle aspiration from a right cervical lymph node was positive. Histopathological examination of the specimen obtained by percutaneous right cervical lymph node biopsy showed necrotizing epithelioid granulomas and no malignant cells. Therefore, right cervical tuberculous lymphadenitis was diagnosed. Partial lung resection of the right S4 was carried out by video-assisted thoracoscopic surgery and primary lung cancer was diagnosed. To our knowledge, there has been no previous report of both primary lung cancer and cervical tuberculous lymphadenitis being present at the time of the first examination. We report this very rare case.

[Optimum preparation of levocarnitine chloride solution in the hospital pharmacy].

Levocarnitine chloride is used for the therapeutic purpose of levocarnitine deficiency. For infants, however, levocarnitine chloride tablets must be crushed to avoid difficulties associated with swallowing, and also to administer an appropriately low dosage. Since the tablet is extremely hygroscopic and sour, it is dissolved in water containing simple syrup after crushing. In this study we investigated the stability of the drug after dissolution to optimize its preparation for clinical use. It was shown to be stable for at least 90 days after preparation, and microbes did not grow in 1-10% (w/v) solutions (pH 2.0-2.5) regardless of the presence or absence of simple syrup. Furthermore, the autoclaved levocarnitine chloride solution was as stable as the non-autoclaved one. In conclusion, the method employed in our hospital for the preparation of levocarnitine chloride for infants is appropriate and is recommended as a standard medicine supply method among different facilities.

Allergic bronchial asthma: airway inflammation and hyperresponsiveness.

The international consensus report on diagnosis and treatment of asthma was published in 1992 (Clin Exp Allergy 22: 1-72). According to the report, asthma is a chronic inflammatory disorder of the airways in which many cells play a role, including mast cells and eosinophils. Airway inflammation causes various symptoms of asthma which are usually associated with widespread but variable airflow obstruction and causes an associated increase in airway responsiveness to a variety of stimuli. The definition of asthma, provided in this report, is an epoch-making revision of the conventional recognition of asthma based on respiratory physiology and does not contradict the empirical knowledge that asthma responds well to steroid therapy. One reason, which led airway inflammation to be understood as a major factor in the pathophysiology of asthma is the technological advance and the widespread use of bronchoscopes. The use of bronchoscopy as a research tool has markedly improved the understanding of the pathology of asthma. It became also possible to link biopsy findings to autopsy findings in patients who died of asthma. However, it is relatively difficult to repeat a biopsy of the airway mucosal membranes in individual asthmatic patients. Here, animal models of asthma play a significant role. Findings from animal models can provide a clue for the development of new anti-asthmatic drugs. This paper will deal with the paradigm of allergic asthma and focus on recent topics of interleukin (IL)-4 and IL-5, which seem to play a central role in allergic asthma. The causative relationship between airway inflammation and hyperresponsiveness will be discussed.

[An autopsy case of protein-losing enteropathy due to gastrointestinal amyloidosis, occurring in empyema].

On August 14, 2001, a 76-year-old woman with a history of rheumatoid arthritis was admitted to our hospital with fever, cough, dyspnea and diarrhea. On admission, her chest radiography showed pleural effusion on the right side, and thoracocentesis was used to diagnose empyema. The patient underwent pleural drainage and received antibiotics. Alpha-Streptococcus was detected in both aerobic and anaerobic cultures of the pleural effusion. After 2 weeks of therapy, her empyema had improved; but her diarrhea, which had started 1 week before admission, had worsened, and her hypoproteinemia had progressed. Examination of the fecal clearance of alpha-1-antitrypsin and biopsied rectal material revealed that the diarrhea was caused by protein-losing enteropathy due to gastrointestinal amyloidosis secondary to rheumatoid arthritis. The patient was treated with steroids, but developed an additional infectious disease and died on September 29, 2001. In this case, she suffered from various infectious diseases including empyema and fungus infections. It has been reported that protein-losing enteropathy accompanies abnormalities in the immune system, by the loss of immunoglobulins and lymphocytes from the gut. We therefore suspect that protein-losing enteropathy due to gastrointestinal amyloidosis caused this patient's empyema.

[A case of tricuspid valve infective endocarditis presenting with multiple nodular shadows in both lungs without known predisposing factors].

A 56-year-old woman was admitted to our hospital with fever, cough, and sputum production. Her chest radiograph and chest computed tomography showed multiple nodules. Laboratory findings revealed leukocytosis and an increased C-reactive protein concentration. Physical examination revealed a systolic murmur. Transesophageal echocardiography demonstrated a 1.5-cm area of vegetation on the tricuspid valve. Blood cultures grew Staphylococcus aureus. Tricuspid valve endocarditis and septic pulmonary embolism were diagnosed. She was treated successfully with intravenous ampicillin/sulbactam. This was a rare case of tricuspid valve infective endocarditis in an adult patient without known predisposing factors.

[A case of desmoplastic malignant mesothelioma with elevated serum CYFRA 21-1].

A 70-year-old woman was admitted to our hospital for medical evaluation of a right side pleural effusion, which was pointed out at another hospital. Chest CT revealed a right pleural effusion with diffuse and irregular pleural thickening. Percutaneous pleural biopsy showed hypocellular collagenous tissue without malignant cells. Though she received antituberculosis therapy, the pleural thickening progressed and the serum CYFRA 21-1 level was elevated. Chest pain and dyspnea appeared, and she was readmitted. However, pneumonia was present as a complication, and she died. At autopsy, the right pleura was thickened and invasion of the lung and the chest wall was observed. Microscopic findings showed increased amounts of hyalinized collagen fibers forming a storiform pattern. At the tumor foci, atypical cells with distinct nucleoli were observed. Desmoplastic malignant mesothelioma, which is rarely reported in Japan, was diagnosed.

[A case in which progressive emphysematous changes were seen on chest computed tomography associated with Pneumocystis carinii pneumonia in a patient with AIDS].

A 60-year-old man was admitted to our hospital complaining of progressive dyspnea. On admission, he had marked hypoxemia, and his chest radiography and computed tomography (CT) showed ground glass opacities and multiple emphysematous changes in both lung fields. On examining the patient's bronchoalveolar lavage fluid (BALF). Pneumocystis carinii pneumonia (PCP) was diagnosed. A serological test for human immunodeficiency virus (HIV)-1, 2 was positive, and acquired immunodeficiency syndrome (AIDS) was diagnosed. Since the chest CT performed a month before the patient's admission to our hospital revealed ground glass opacities in both lung fields we thought that he had already developed PCP at that time. In comparison with his previous CT, the chest CT on admission showed progressive ground glass opacities and emphysematous changes. Although PCP is known to display various findings on chest radiography and CT, emphysematous changes are rarely reported in Japan. In this case we were able to confirm these changes and observe its progression using chest CT.