Effective cryoablation of a lateral accessory pathway within the distal coronary sinus

Limited information is available on the efficacy of cryoablation in the coronary venous system in humans. A patient with a lateral accessory pathway was referred to our center after several unsuccessful endocardial and epicardial (within the coronary sinus) attempts using standard radiofrequency energy. Ablation was subsequently performed successfully by applying cryoenergy distally into the coronary sinus, using a temperature of -50 degrees C and a freezing application time of 45 s. There were no complications. Angiography of the left coronary circumflex artery and coronary venous system was performed at 12 months follow-up using cardiac multislice computed tomography, and no coronary stenosis or anatomic anomaly was found. Neither pre-excitation or any arrhythmia recurred during follow-up. This experience suggests that ablating in the distal coronary sinus can be safely performed using cryoenergy.     

Spotlight on Insulin Aspart in Type 1 and 2 Diabetes Mellitus

Insulin aspart (NovoLog, NovoRapid), a rapid-acting human insulin analog, provides more rapid absorption than regular human insulin after subcutaneous administration. In most randomized, nonblind clinical trials in patients with type 1 diabetes mellitus, insulin aspart administered immediately before meals resulted in significantly lower mean glycosylated hemoglobin (HbA1c) levels than regular human insulin (usually administered 30 minutes before a meal). Insulin aspart also significantly improved postprandial glycemic control compared with regular human insulin. The efficacy of insulin aspart was similar to that of insulin lispro when administered to patients with type 1 diabetes mellitus via continuous subcutaneous infusion in a randomized, nonblind trial. Preliminary data from randomized, nonblind trials suggest insulin aspart had a trend towards lower HbA1c levels compared with regular human insulin in patients with type 2,diabetes mellitus. Biphasic insulin aspart (30% soluble [rapid-acting] and 70% protamine-bound insulin aspart [BIAsp30]) [NovoLog Mix 70/30, NovoMix 30(2)] generally provided significantly better postprandial glucose control than a similar mixture of biphasic regular human insulin (BHI30) in a randomized, nonblind trial in patients with type 1 or 2 diabetes mellitus. However, the long-term efficacy of BIAsp30 was similar to that of BHI30 after 2 years in a randomized, nonblind trial in patients with type 2 diabetes mellitus. Patients with type 1 or 2 diabetes mellitus reported greater treatment satisfaction with insulin aspart or BIAsp30 than with regular human insulin or BHI30. The overall incidence of hypoglycemia with insulin aspart was lower than, or similar to, that of regular human insulin. Moreover, insulin aspart tended to be associated with a lower occurrence of nocturnal hypoglycemia and severe hypoglycemic events than regular human insulin. Conclusion: The standard preparation of insulin aspart has the potential to better mimic the physiological response to meals than regular human insulin. Insulin aspart when combined with a suitable basal insulin improved overall glycemic control and led to a similar or lower number of hypoglycemic episodes compared with a similar regular human insulin regimen. Insulin aspart was generally as effective and well tolerated as insulin lispro when administered by continuous subcutaneous infusion in a single comparative trial. The efficacy of biphasic insulin aspart has been documented in a small number of trials. Both insulin aspart and biphasic insulin aspart provide for flexible and convenient administration. Insulin aspart is now well established as an effective and convenient means of providing glycemic control which offers clinical and practical advantages over regular human insulin.     

Expression of vascular endothelial growth factor and receptor flk-1 in colon cancer liver metastases

Background/Purpose

This study investigated vascular endothelial growth factor (VEGF) and flk-1 expression in hepatic metastases from colon carcinoma, and their associations with tumor angiogenesis, proliferation, and apoptosis.

Methods

Immunohistochemical studies were performed for VEGF/flk-1, Ki-67, p53, and bcl-2 expression, and microvessel density (MVD) in surgical specimens from 35 patients who underwent hepatectomy for colon cancer liver metastases between 1986 and 2001.

Results

VEGF and flk-1 were expressed mainly in the cytoplasm of tumor cells. High VEGF expression was associated with high flk-1 expression (P = 0.043). MVDs of less than 15 and 15 or more were found in 5 (14.3%) and 30 (85.7%) of 35 hepatic metastases, respectively. A Ki-67 index (KI) of 50% or more was detected in 33/35 (94.3%) of tumors, and 23 of these (65.7%) showed a KI of 85% or more. A KI of less than 50% was present in 2/35 (5.7%) of tumors. The expression of VEGF/flk-1 was related to elevated MVD (P ≤ 0.026). VEGF was also associated with an increased KI (P = 0.025). Mutant p53 and bcl-2 expressions were detected in 26/35 (74.3%) and 17/35 (48.6%) of liver metastases, respectively. Mutant p53 was not related to VEGF/flk-1 expression, but bcl-2 was highly associated with flk-1 (P = 0.007). The incidences of high flk-1 expression and a KI of 85% or more were significantly higher in tumors which were both p53- and bcl-2-positive (93.3% and 73.3%) than in tumors which were negative for both (42.9% and 14.3%; P ≤ 0.021).

Conclusions

The VEGF-flk-1 system takes part in tumor angiogenesis, proliferation, and apoptosis in colon liver metastases. The bcl-2 pathway may upregulate VEGF activity via the flk-1 receptor. These findings are preliminary, requiring a larger sampling in order to elucidate the role of VEGF/flk-1 in metastatic colon cancer.

     

A case of longitudinally extensive transverse myelitis (LETM): neuromyelitis optica

Neuromyelitis optica (NMO), characterised by longitudinally extensive transverse myelitis (LETM), was previously thought to be a variant of multiple sclerosis. Transverse myelitis may be a manifestation of autoimmune connective tissue diseases and NMO is now recognised to be a humorally mediated autoimmune disease. We present a case of NMO associated with non-organ-specific autoantibodies and the absence of the characteristic NMO-IgG antibody. Our case provides an opportunity to review the diagnostic criteria of NMO and its distinction from other autoimmune and demyelinating conditions. We report successful treatment with plasmapheresis and rituximab in NMO-IgG-negative relapsing disease.     

Anatomical Variations in Stylopharyngeus Muscle Insertions Suggest Interindividual and Left/Right Differences in Pharyngeal Clearance Function of Elderly Patients: A Cadaveric Study

The stylopharyngeus plays a critical role in the clearance of the piriform recess. We dissected 78 sides of the pharynx from 55 donated cadavers and observed histology of another seven sides of the pharynx from seven cadavers. The stylopharyngeus consistently comprised (1) a descending muscle bundle surrounding the piriform recess and (2) an additional short sheet inserting into the tonsillar bed. Histologically, the former bundle connected to a thick fascia providing the lateral glossoepiglottic fold, extending along the submucosa of the piriform recess, and covering the thyroid cartilage, whereas the latter sheet intermingled with other pharyngeal wall muscles at and near the tonsillar bed. Notably, in 44.4% of female specimens, the additional sheet occupied a greater proportion in cross section than the descending muscle bundle. Given the different directions, the additional sheet seemed to check clearance function of the descending bundle for the piriform recess. Thus, particularly in women, interindividual differences in pharyngeal clearance were likely to depend on whether the additional sheet is strong or weak. Chin down in combination with tilting and rotating the head may represent effective exercises of the stylopharyngeus that could compensate for the disadvantages of additional insertion.     

Evaluation of the depth score of type V pit patterns in crypt orifices of colorectal neoplastic lesions

Background We developed and evaluated the clinical usefulness of a scoring system that subclassified type Vi pit patterns. Methods We studied 119 colon cancer lesions (pTis, n = 26; pT1, n = 93) and 22 tubular adenoma lesions with severe atypia in which a type Vi pit pattern was visible under a stereomicroscope. Four type Vi pit pattern formation appearances (existing pits, marginal irregularities of the gland duct, narrowing of the gland duct lumen, and unclear outline of the gland duct) were defined, and the relationship between each appearance and the invasive depth of the cancer was evaluated. Results When the four type Vi pit pattern appearances were considered in a logistic regression analysis, the odds of a more invasive submucosal cancer were significantly increased by the appearance of marginal irregularities, a narrowed lumen, and an unclear outline. In the logistic regression analysis results, when 0.63 was used as the cutoff score for prediction of a more invasive submucosal cancer, 80 cases in the less invasive group were classified correctly (specificity, 1.0), whereas 53 (86.9%) of the 61 cases in the more invasive group were classified correctly (sensitivity, 0.869). Conclusions It is important first to understand the usability and limitations of objective scoring of type V pit pattern findings and then to apply this score to the determination of cancer depth in order to accurately identify lesions suitable for endoscopic treatment.     

Comparison of gastric peristalsis inhibition by scopolamine butylbromide and glucagon: evaluation by electrogastrography and analysis of heart rate variability

Background. Activation of glucagon receptors of the smooth muscle membrane suppresses gastric peristalsis. We evaluated autonomic nervous activity by two methods, electrogastrography (EGG) and analysis of heart rate variability, to compare the inhibiting effects of glucagon and scopolamine butylbromide on gastric peristalsis. Methods. Heart rate variability, EGG, and blood catecholamine levels were measured before and after administration of glucagon (G group), scopolamine butylbromide (SB group), or physiological saline (C group). Autonomic nervous function was evaluated using spectral analysis of heart rate variability, and low frequency (LF) and high frequency (HF) power; the LF/HF ratios were also determined. Results. After administration of scopolamine butylbromide, HF power, an index of parasympathetic nervous activity, decreased; and the LF/HF ratio, an index of sympathetic nervous activity, increased. In contrast, no significant change was observed in autonomic nervous activity after administration of glucagon. The peak power amplitudes of the EGG decreased significantly in the G and SB groups after intramuscular injection, but the difference between the groups was not significant. Furthermore, the dominant frequency increased significantly in the G and SB groups after injection. Serum catecholamine levels showed no significant changes after administration of scopolamine butylbromide or glucagon. Conclusions. Inhibition of gastric peristalsis by glucagon via glucagon receptors on smooth muscles did not influence autonomic nervous activity, unlike the results obtained after administration of scopolamine butylbromide. Therefore, glucagon may be safe for use with elderly patients and those with cardiopulmonary complications.     

Improvement of endothelial dysfunction by angiotensin II blockade accompanied by induction of vascular hepatocyte growth factor system in diabetic spontaneously hypertensive rats

 Hepatocyte growth factor (HGF) is a unique growth factor with many protective functions. Previously, we demonstrated that HGF stimulated growth of endothelial cells without replication of vascular smooth muscle cells (VSMC) and that angiotensin (Ang) II significantly decreased local HGF production in VSMC. Moreover, we also reported that high glucose significantly decreased local vascular HGF production. Therefore, we examined effects of Ang II blockade on vascular HGF expression and endothelial injury in diabetic hypertensive rats. An angiotensin-converting enzyme inhibitor (quinapril) and an Ang II type 1 receptor antagonist (GA-0113) or vehicle was administrated to diabetic spontaneously hypertensive rats (SHR-DM), in whom diabetes was induced by streptozotocin. Endothelial function was evaluated by the vasodilator response to acetylcholine, and the expression of vascular HGF and its receptor, c-met, was examined by immunohistochemistry. Both quinapril and GA-0113 significantly improved the vasodilator response to acetylcholine (P < 0.01), while vehicle did not as compared to untreated normotensive Wistar-Kyoto rats (WKY). We next examined the effects of Ang II blockade on vascular HGF expression in SHR-DM. Importantly, the vascular HGF level was markedly decreased in SHR-DM as compared to WKY, while Ang II blockade by quinapril or GA-0113 significantly increased positive staining for HGF in SHR-DM. Similarly, staining of its specific receptor, c-met, was less in the blood vessels of SHR-DM as compared to WKY. In contrast, Ang II blockade also significantly increased c-met production in SHR-DM. The present data demonstrated the improvement of endothelial dysfunction by Ang II blockade in SHR-SM, accompanied by an increase in vascular HGF and c-met. Received: June 7, 2002 / Accepted: September 21, 2002 Acknowledgments We wish to thank Rie Kosai and Keiko Yamaguchi for their excellent technical assistance. This work was partially supported by grants from the Japan Health Sciences Foundation, a Grant-in-Aid from The Ministry of Public Health and Welfare, a Grant-in-Aid for the Development of Innovative Technology, a Grant-in-Aid from Japan Promotion of Science, and through Special Coordination Funds of the Ministry of Education, Culture, Sports, Science and Technology, the Japanese Government. Correspondence to N. Tomita     

Oral Alimentation in Neonatal and Adult Populations Requiring High-Flow Oxygen via Nasal Cannula

Use of high-flow oxygen via nasal cannula (HFO₂-NC) is increasingly common in intensive care unit (ICU) settings. Despite the critical interface between respiration and swallowing, and the high acuity of patients in ICUs, the impact of HFO₂-NC on feeding and swallowing is unknown. The present prospective, single-center, cohort study investigated the impact of HFO₂-NC use on oral alimentation in neonatal and adult ICU patients. Oral alimentation status was evaluated in 100 consecutive ICU inpatients (50 neonatal and 50 adult) requiring HFO₂-NC. Participant characteristics, respiratory support, successful initiation of oral feeding in neonates, and successful resumption of oral feeding in adults were recorded. Seventeen of 50 (34 %) neonates requiring HFO₂-NC were deemed developmentally and medically appropriate by the neonatologist and nursing to begin oral alimentation. All 17 (100 %) were successful with initiation of oral feedings. Thirty-three of 50 (66 %) continued nil per os due to prematurity or medical conditions precluding oral alimentation at time of data collection. Thirty-nine of 50 (78 %) adults requiring HFO₂-NC were deemed medically appropriate by the intensivist and nursing to resume oral alimentation (n = 34) or with a functional swallow without aspiration on FEES (n = 5). All 39 (100 %) resumed oral alimentation successfully. Eleven of 50 (22 %) continued nil per os due to severe respiratory issues precluding both swallow testing and oral alimentation at time of data collection. All developmentally and medically appropriate neonatal and adult patients requiring HFO₂-NC were successful with either the introduction or resumption of oral alimentation. Patients requiring HFO₂-NC who are identified as having feeding or swallowing issues should be referred for swallowing evaluations using the same criteria as patients who do not require HFO₂-NC, as it is not the use of HFO₂-NC but rather patient-specific determinants of feeding and swallowing readiness and their underlying medical conditions that impact readiness for oral alimentation status.