Temporary strecker stent for management of acute dissection in popliteal and crural arteries

Stent placement is a widely used bail-out treatment for dissection of peripheral arteries. Below the level of the superficial femoral artery permanent stenting is complicated by a high incidence of subacute thrombosis and restenosis. We present two cases of arterial occlusion due to acute iatrogenic dissection of the popliteal and distal fibular arteries. Successful treatment was achieved with a new bail-out procedure. Strecker stents were implanted to seal off the dissection flap. Stents were retrieved easily after 24 hr using a myocardial biopsy forceps. After stent retrieval the temporarily stented segments were patent and showed a larger lumen compared with segments treated by balloon dilatation alone. Temporary stenting is a simple and safe procedure and offers the advantage of tacking up dissection membranes and preventing recoil. Persistent presence of a metallic implant as a source of continued injury and stimulus for intimal proliferation is avoided.     

A molecular scheme for the reaction between γ-aminobutyric acid and the most abundant chloride channel on crayfish deep extensor abdominal muscle

Single-channel measurements were performed with the aim of constructing a detailed molecular scheme for the reaction between -aminobutyric acid (GABA) and a chloride channel of crayfish deep extensor abdominal muscle (DEAM). GABA was applied in pulses to outside-out patches of muscle membrane, and, based on the dose-response of the peak currents and of their rise times, a linear model with five binding steps has been proposed. Evaluation of the single-channel kinetics indicated at least three open states. Two of them originate most probably from the fully liganded receptor state and are grouped in mixed bursts due to their different life times. The third one appears independently, outside the bursts, and originates from a lower liganded receptor state. Simulations of the dose-responses and the open time distributions with this model led to a set of rate constants which generated relatively optimal fits.     

Postocclusive cutaneous vasodilatation mediated by substance P

1. The cutaneous vasodilatation following arterial occlusion ("reactive hyperemia") was studied in the rat hind paw. A peak increase in venous outflow of 200-250% was observed within 1 min after a 3 min occlusion period. 2. Chronic denervation as well as capsaicin pretreatment reduced the postocclusive cutaneous vasodilatation by more than 60% (P less than 0.01). This demonstrates that the reactive vasodilatation is of neurogenic origin and mediated by small diameter afferent fibres. 3. Reduction of the postocclusive cutaneous vasodilatation after histamine depletion by compound 48/80 indicates the involvement of histamine. 4. Among all neuropeptides known to occur in primary sensory neurones only substance P and vasoactive intestinal polypeptide cause vasodilatation when infused i.a. into the rat paw. In contrast to antidromic sensory nerve stimulation or i.a. substance P infusion, vasoactive intestinal polypeptide does not cause plasma extravasation. The vasodilator potency of vasoactive intestinal polypeptide is about 1/500 of substance P in the rat paw. Therefore only substance P is able to mimic the reactive vasodilatation. 5. It is concluded that the postocclusive cutaneous vasodilatation is caused mainly by the release of substance P from peripheral endings of small diameter nerve fibres. The "axon reflex", also involving neurogenic vasodilatation, is assumed to be exerted by the same mechanism.     

The pathophysiology of enterocutaneous fistulas

The patient with an enterocutaneous fistula represents a high-risk situation with overall mortality rates of up to 20%, depending on the series. Treatment of these patients to a successful outcome requires attention to detail and, if necessary, meticulous operative technique. For convenience, care of these patients is divided into 5 phases:

1. Stabilization. Resuscitation with crystalloid colloid and/or blood. Drainage of only obvious abscesses. Beginning of local wound care. Initiation of nutritional support.
2. Investigation. Radiographic investigation of local fistula area, principally by sinography and, if necessary, other contrast studies. Purpose of these studies is to determine likelihood of spontaneous closure with nutritional support.
3. Decision. Is operation indicated and, if so, when? A decision must be made as to the necessity for operative closure in situations in which the fistula appears anatomically favorable but shows no signs of closure.
4. Definitive therapy—either spontaneous closure or operation. If the latter, careful preparation is required. Resection and end-to-end anastomosis gives the best results.
5. Healing phase. Nutritional support should not be discontinued too soon for fear of breakdown of newly laiddown protein.

With experience and proper management, relatively high success rates can be achieved.     

Changes in Intestinal Transit Time after Proctocolectomy Assessed by the Lactulose Breath Test

After proctocolectomy with ileal pouch-anal anastomosis (IPAA) patients have increased stool frequency and intermittently use antidiarrheal medication. In addition to other factors, gastrointestinal transit time (MTT) could influence stool frequency. The aim of this study was to investigate how MTT changes after IPAA and to study whether MTT has an influence on daily stool frequency. In a prospective trial MTT was investigated with the lactulose breath test in 12 patients undergoing surgery for chronic ulcerative colitis (CUC) or familial adenomatous polyposis coli (FAPC) at different stages: before proctocolectomy, after IPAA with loop ileostomy, and 3 months and 1 year after ileostomy closure. MTT was also measured in 12 patients with IPAA, 12 patients with subtotal colectomy and ileorectal anastomosis (IRA), and 8 patients with conventional proctocolectomy and Brooke ileostomy (CPC) several years after surgery. Twelve healthy volunteers served as controls. Before IPAA, MTT was prolonged in CUC versus FAPC and controls. After restoration of gut continuity MTT was markedly accelerated. After 1 year MTT was slowed again, though values before proctocolectomy and those in controls were not reached. Several years after surgery MTT was significantly prolonged in IPAA and IRA versus controls. In CPC, MTT could not be determined by lactulose breath test. Stool frequency showed an inverse correlation to MTT in IPAA. In conclusion, this study shows that orocecal and oropouch transit are accelerated in the early postoperative period after (procto)colectomy but prolonged in the long-term course. Adaptation of the small bowel takes longer than 1 year. Impairment of stool frequency may be partly due to this adaptation.     

免疫营养素与新生儿感染

胃肠道拥有人体最大的表面积,它是微生物、异种抗原以及毒素进入宿主内环境的主要场所.胃肠道是全身炎症反应综合征的起源地,随着对肠道在炎症发生和多器官衰竭中作用认识的提高,具有免疫增强功能的肠内营养正日益引起人们的关注.本文将讨论谷氨酰胺、精氨酸、核苷酸以及乳铁蛋白等营养素参与机体免疫调节的机制和它们作为免疫营养素在新生儿感染中的临床应用前景.     

Prevalence of Personality Disorders Among Combat Veterans with Posttraumatic Stress Disorder

Many combat veterans with PTSD have co-occurring symptoms of other forms of psychopathology; however, there have been limited studies examining personality disorders among this population. The few extant studies typically have assessed only two or three personality disorders or examined a small sample, resulting in an incomplete picture and scope of comorbidity. This study assessed all DSM-III-R personality disorders in 107 veterans in a specialized, inpatient unit. Using the Structured Clinical Interview for DSM-III-R Personality Disorders, 79.4% of the participants were diagnosed with at least one personality disorder: 29.9% received only one diagnosis, 21.5% had two, 15.9% had three, and 12.1% had four or more. The most frequent single diagnoses were Avoidant (47.2%), Paranoid (46.2%), Obsessive-Compulsive (28.3%), and Antisocial (15.1%) personality disorders.(116B)(116B-2)(323-E112)     

Tirapazamine plus carboplatin and paclitaxel in advanced malignant solid tumors: a california cancer consortium phase I and molecular correlative study.

PURPOSE: Tumor hypoxia confers chemotherapy resistance. Tirapazamine is a cytotoxin that selectively targets hypoxic cells and has supra-additive toxicity with platinums and taxanes in preclinical studies. We conducted a Phase I study of tirapazamine, carboplatin, and paclitaxel and assessed potential plasma markers of hypoxia as surrogates for response. EXPERIMENTAL DESIGN: Forty-two patients with advanced solid tumors were treated at four dose levels; parallel dose escalations were carried out in chemotherapy-naive and previously treated subjects. Pre and post-therapy plasma levels of the hypoxia-induced proteins plasminogen activator inhibitor-1 and vascular endothelial growth factor were measured. RESULTS: Three of four chemotherapy-na?ve patients developed dose-limiting toxicities at dose level 4 (grade 3 stomatitis/infection, grade 3 emesis, and grade 4 febrile neutropenia). Four of seven previously treated patients developed dose-limiting toxicities at dose level 3, including one death [grade 3 myalgia, grade 3 infection/grade 4 neutropenia, grade 3 infection/grade 4 neutropenia, and grade 5 infection (death)/grade 4 neutropenia]. Of 38 patients assessable for response, 3 had a complete response, 1 a partial response, 1 an unconfirmed partial response, and 23 had stable disease in at least one evaluation; 10 quickly progressed. One complete responder had normalization of vascular endothelial growth factor and plasminogen activator inhibitor-1 levels. CONCLUSION: Dose levels 3 (carboplatin AUC of 6, 225 mg/m(2) paclitaxel, and 330 mg/m(2) tirapazamine) and 2 (carboplatin AUC 6, 225 mg/m(2) paclitaxel, and 260 mg/m(2) tirapazamine) are the maximum tolerated doses for chemotherapy naive and patients treated previously, respectively. Dose level 3 is the experimental arm of a Phase III Southwest Oncology Group trial (S0003) in advanced non-small cell lung cancer. Potential markers of tumor hypoxia may be useful correlates in studies of hypoxic cytotoxins and are being prospectively investigated in S0003.     

HER2 status in non-small cell lung cancer: results from patient screening for enrollment to a phase II study of herceptin.

PURPOSE: For the first time a large number (563) of non-small cell lung cancer (NSCLC) samples was used to compare three different technologies for the assessment of HER2 status. Fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) were used for tumor tissue samples, and ELISA for serum samples. The results were compared with other tumor entities, mainly breast. EXPERIMENTAL DESIGN: Samples (563) from patients suffering from primary advanced or metastatic NSCLC were evaluated. RESULTS: HER2 overexpression was demonstrated using IHC in 20% (83 of 410) of the specimens, whereas 2% (7 of 378) were positive by FISH and 6% (31 of 511) showed elevated serum HER2 levels (>15 ng/ml) by ELISA. Sixty-six specimens were positive by IHC only and 13 by ELISA only, whereas none of the specimens was positive only by FISH. Concordance between all of the techniques was seen for only 3 specimens. Of 7 IHC 3+ specimens, 4 showed gene amplification by FISH, and 3 were positive by ELISA (>15 ng/ml), whereas of 76 IHC 2+ cases only 2 were amplified by FISH, and 4 were positive by ELISA. HER2 positivity by at least one of the three techniques was most common in adenocarcinomas, at 29% (42 of 143). CONCLUSION: Gene amplification and HER2 protein overexpression at the 3+ level appear to be uncommon in NSCLC. The concordance between FISH and IHC 3+ disease was good in this study, in addition, ELISA would have detected several patients without IHC/FISH-positive disease.