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51.
A disintegrin and metalloproteinase 3 (ADAM3) is a sperm membrane protein critical for both sperm migration from the uterus into the oviduct and sperm primary binding to the zona pellucida (ZP). Here we show that the testis-specific protein disulfide isomerase homolog (PDILT) cooperates with the testis-specific calreticulin-like chaperone, calsperin (CALR3), in the endoplasmic reticulum and plays an indispensable role in the disulfide-bond formation and folding of ADAM3. Pdilt(-/-) mice were male infertile because ADAM3 could not be folded properly and transported to the sperm surface without the PDILT/CALR3 complex. Peculiarly we find that not only Pdilt(-/-), but also Adam3(-/-), spermatozoa effectively fertilize eggs when the eggs are surrounded in cumulus oophorus. These findings reveal that ADAM3 requires testis-specific private chaperones to be folded properly and that the principle role of ADAM3 is for sperm migration into the oviduct but not for the fertilization event. Moreover, the importance of primary sperm ZP binding, which has been thought to be a critical step in mammalian fertilization, should be reconsidered.  相似文献   
52.
53.
CTX-M-19 is a recently identified ceftazidime-hydrolyzing extended-spectrum beta-lactamase, which differs from the majority of CTX-M-type beta-lactamases that preferentially hydrolyze cefotaxime but not ceftazidime. To elucidate the mechanism of ceftazidime hydrolysis by CTX-M-19, the beta-lactam MICs of a CTX-M-19 producer, and the kinetic parameters of the enzyme were confirmed. We reconfirmed here that CTX-M-19 is also stable at a high enzyme concentration in the presence of bovine serum albumin (20 micro g/ml). Under this condition, we obtained more accurate kinetic parameters and determined that cefotaxime (k(cat)/K(m), 1.47 x 10(6) s(-1) M(-1)), cefoxitin (k(cat)/K(m), 62.2 s(-1) M(-1)), and aztreonam (k(cat)/K(m), 1.34 x 10(3) s(-1) M(-1)) are good substrates and that imipenem (k(+2)/K, 1.20 x 10(2) s(-1) M(-1)) is a poor substrate. However, CTX-M-18 and CTX-M-19 exhibited too high a K(m) value (2.7 to 5.6 mM) against ceftazidime to obtain their catalytic activity (k(cat)). Comparison of the MICs with the catalytic efficiency (k(cat)/K(m)) of these enzymes showed that some beta-lactams, including cefotaxime, ceftazidime, and aztreonam showed a similar correlation. Using the previously reported crystal structure of the Toho-1 beta-lactamase, which belongs to the CTX-M-type beta-lactamase group, we have suggested characteristic interactions between the enzymes and the beta-lactams ceftazidime, cefotaxime, and aztreonam by molecular modeling. Aminothiazole-bearing beta-lactams require a displacement of the aminothiazole moiety due to a severe steric interaction with the hydroxyl group of Ser167 in CTX-M-19, and the displacement affects the interaction between Ser130 and the acidic group such as carboxylate and sulfonate of beta-lactams.  相似文献   
54.
It is necessary to use side clamps to construct proximal anastomoses in off-pump coronary artery bypass, and this can be related to neurologic complications. Recently a new device, the HEARTSTRING device, was developed. We present a 78-year-old man who underwent emergent bypass surgery using the HEARTSTRING device to avoid a side clamp. We found atherosclerotic debris from the punched hole and, unfortunately, a postoperative neurological complication resulted. We strongly suggest that it is most important that potential candidates for the HEARTSTRING device be carefully selected to reduce possible neurologic complications. We report that while this new device is useful, there is a potential pitfall in using it; that it is a possible source of atheroembolism.  相似文献   
55.

Background

ALCL99 protocol including six courses of chemotherapy derived from the NHL‐BFM protocol is widely used for the treatment of paediatric anaplastic large‐cell lymphoma. In the ALCL99 trial, patients were randomised to receive MTX 1 g/m2 in 24 hr with intrathecal injection (MTX1) versus MTX 3 g/m2 in 3 hr without intrathecal (MTX3); then to receive or not vinblastine (high‐risk patients). The present study provides information about the acute adverse reactions (ARs) during the six courses of the ALCL99 treatment, assesses risk factors for ARs and evaluates the risk of overweight related to treatment.

Methods

Data concerning ARs were assessed using CTCv2 and analysed overall and according to the type of course.

Results

Between 1999 and 2005, 352 patients were recruited. Toxicity assessed after 2050 courses included grade 4 neutropaenia (70% of courses), grade 3–4 stomatitis (13%), grade 3–4 transaminase elevation (10%) and grade 3–4 infection (5%). Four patients (1%) died of toxicity. The toxicity profile differed between courses‐A (significantly more haematological toxicity) and courses‐B (significantly more stomatitis). The percentage of ARs was higher after the first course than after subsequent courses. Severe toxicity was more frequent after MTX1 than after MTX3 courses but did not differ between courses with or without vinblastine. Overall 20% of patients had a weight gain exceeding 20%.

Conclusions

The high rate of acute toxicity should be considered when using the ALCL99 protocol. Chemotherapy including MTX 3 g/m2 in 3 hr was less toxic than the same regimen with MTX 1 g/m2 in 24 hr. Adding vinblastine did not increase the risk of toxicity. Pediatr Blood Cancer 2011;56:1071–1077. © 2011 Wiley‐Liss, Inc.  相似文献   
56.
In this report, we provide evidence using a serial bone marrow transplantation (BMT) protocol that intra-bone marrow (IBM)-BMT (IBM-BMT) can efficiently reconstitute the hemopoietic system with cells of donor origin, in contrast to conventional intravenous (IV)-BMT (IV-BMT). Furthermore, the hematolymphoid system of secondary recipients that had received bone marrow cells (BMCs) from primary recipients treated with IBM-BMT recovered earlier than that of the secondary recipients of BMCs from primary recipients treated with IV-BMT. This was the case when the Lin-/c-kit+ progenitor cells of the secondary and tertiary recipients were examined. These findings indicate that IBM-BMT can facilitate the development of not only cells of various lineages but also the effective generation and, more importantly, the maintenance of the progenitor cells. Furthermore, we show that IBM-BMT can reconstitute the dendritic cell (DC) subsets (myeloid and lymphoid DCs), which are critical for the initiation of both adaptive and innate immune responses. The frequency of both myeloid and lymphoid DC subsets was approximately equal to that of normal age-matched untreated controls and, after second and third BMT, this ratio was close to that observed in the normal controls. However, the lymphoid DCs were clearly reduced in the secondary and tertiary recipients of BMCs from mice that had received IV-BMT. Therefore, the development of DC subsets is also normally maintained in the IBM-BMT group.  相似文献   
57.
Effects of four novel atypical antipsychotic drugs (olanzapine, perospirone, quetiapine, and risperidone) on scalp-recorded multi-channel EEGs were compared with two conventional antipsychotic drugs (chlorpromazine and haloperidol) and placebo in 14 healthy male volunteers. All subjects went through seven sessions. In each session, EEGs were recorded before and 2, 4 and 6 hours after drug administration. Global Field Power (GFP) in delta frequency band (1.5-6 Hz) increased around the time of peak serum concentration of quetiapine and risperidone compared to baseline. The increase of GFP in delta activity after quetiapine was significantly prominent in comparison to two other atypical antipsychotic drugs, perospirone and olanzapine, as well as to typical antipsychotic drugs, chlorpromazine and haloperidol (p<0.05). The increase in GFP of delta after risperidone was more prominent in comparison to after haloperidol (p<0.05). The greater sedative effects after quetiapine and risperidone may reflect the high affinity to A1 and H1 receptor bindings of these drugs. According to Low Resolution Electromagnetic Tomography (LORETA), olanzapine increased the delta in the posterior region indicating a frontal shift of brain activity, suggesting that olanzapine may be useful against negative symptoms in schizophrenics.  相似文献   
58.
We defined mixed-dust pneumoconiosis (MDP) pathologically as a pneumoconiosis showing dust macules or mixed-dust fibrotic nodules (MDF), with or without silicotic nodules (SN), in an individual with a history of exposure to mixed dust. We defined the latter arbitrarily as a mixture of crystalline silica and nonfibrous silicates. According to our definition of MDP, therefore, MDF should outnumber SN in the lung to make a pathologic diagnosis of MDP. In the absence of confirmation of exposure, mineralogic analyses can be used to support the pathologic diagnosis. The clinical diagnosis of MDP requires the exclusion of other well-defined pneumoconioses, including asbestosis, coal workers’ pneumoconiosis, silicosis, hematite miners’ pneumoconiosis, welders’ pneumoconiosis, berylliosis, hard metal disease, silicate pneumoconiosis, diatomaceous earth pneumoconiosis, carborundum pneumoconiosis, and corundum pneumoconiosis. Typical occupations associated with the diagnosis of MDP include metal miners, quarry workers, foundry workers, pottery and ceramics workers, and stonemasons. Irregular opacities are the major radiographic findings in MDP (ILO 1980), in contrast to silicosis, in which small rounded opacities predominate. Clinical symptoms of MDP are nonspecific. MDP must be distinguished from a variety of nonoccupational interstitial pulmonary disorders.  相似文献   
59.
60.
We assessed the occurrence of atypical adenomatous hyperplasia (AAH) in whole lung lobes with primary cancer lesions. Following surgical resection, tissue specimens were sliced to a thickness of 4 mm (3,641 specimens from 61 cases; mean = 59.7 specimens per case). A total of 119 AAH foci were found and an association was evident in 25 (57%) of 44 adenocarcinomas, 3 (30%) of 10 squamous cell carcinomas, and 2 (29%) of 7 other lung cancers. Histologic evaluation showed that 108 AAH foci were categorized as low-grade and the other 11 as high-grade AAH. These 11 foci of high-grade AAH were present in 7 patients with adenocarcinoma, and in 1 patient there was a synchronous double primary lung adenocarcinoma. High-grade AAH was closely associated with bronchioloalveolar carcinoma (BAC) type adenocarcinoma, and low-grade AAH with non-BAC adenocarcinoma. The mean +/- SD Ki-67 labeling index in high-grade AAH (3.5%+/-2.9%) was significantly higher than for the low-grade index (1.4%+/-1.6%). We propose that foci of high- but not low-grade AAH may be potential precursor lesions of lung adenocarcinoma, especially with the BAC component.  相似文献   
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