Use of a tunneling device to aid in positioning of a graft

A tunneling device can be used to ensure easy placement of a prosthetic or autogenous graft. This can be done without the danger of the graft twisting, kinking or having the clips and ties pulled off. The often frustrating problem of ensuring that the arterial graft lies properly in position can be greatly simplified with the use of this technique.     

ANGIOTENSIN II ACTIVATES PRESSOR AND DEPRESSOR SITES OF THE PONTOMEDULLA THAT REACT TO GLUTAMATE

1. In cats anaesthetized with a mixture of α-chloralose (40 mg/kg) and urethane (400 mg/kg) and in rats anaesthetized with a mixture of α-chloralose (60 mg/kg) and urethane (800 mg/kg), changes in systemic arterial pressure (SAP), heart rate (HR) and sympathetic activities of vertebral (VNA) and renal (RNA) nerves were determined following the micro-injection of angiotensin II (AngII; 0.16 mmol/L; 50 nL) into the pressor and depressor sites of the pontomedulla previously reacted to a microinjection of monosodium l -glutamate (Glu; O.1 mol/L; 50 nL). Pressor sites included gigantocellular tegmental field (FTG) and dorsal medulla (DM) and rostral ventrolateral medulla (VLM). The depressor site was the caudal VLM (CVLM). The effects of losartan (1 mmol/L; 50 nL), a specific AT₁ receptor non-peptide antagonist for AngII, on responses induced by AngII in the VLM, DM and CVLM were also determined. 2. In 30% of pressor sites in the FTG, 55% in the VLM and 67% in the DM and in 76% of depressor sites in the CVLM previously exposed to Glu, microinjection of AngII to the same site produced pressor or depressor responses similar to that of Glu, but smaller in magnitude, particularly in the pressor VLM. Changes in both VNA and RNA induced by AngII were also smaller than those induced by Glu, particularly RNA from DM activation. 3. In the dorsal motor nucleus of the vagus, AngII, as Glu, produced marked bradycardia, but again this was smaller in magnitude than the bradycardia produced by Glu. 4. In rats, in the DM near or around the nucleus of the solitary tract where Glu increased SAP, microinjection of AngII (0.8 mmol/L; 60 nL) produced a depressor response, while the microinjection of 1.6 mmol/L (60 nL) AngII produced a pressor response. 5. Losartan blocked the increases in SAP induced by AngII in the VLM and DM. Decreases in SAP induced by AngII in the CVLM, however, were only slightly decreased by losartan. 6. Our data suggest that a significant portion of pressor and depressor sites of the pontomedulla contain neurons responsive to both AngII and Glu. In neurons in the VLM and DM, AngII produced pressor responses that were primarily mediated through AT₁ receptors, while the depressor actions of AngII in the CVLM were not mediated by AT₁ receptors.     

褐藻酸钠的贮藏稳定性及分子量参数测定

用高效凝胶色谱法和粘度法观察了褐藻酸钠在常温和热加速条件下的分子量参数变化。结果表明,以40℃热加速条件下每天的粘度下降率,可以近似地估计为常温条件下贮藏一星期的粘度下降水平。在贮藏过程中,褐藻酸钠的Mn下降率明显高于Mw,形成的低分子片段是影响其分子量参数变化的主要因素,其分子量分布随贮藏时间延长而逐渐加宽。热加速处理可能降低褐藻酸钠的贮藏稳定性,氮气和真空作为保护气氛不能提高褐藻酸钠的贮藏粘度稳定性。     

Split-thickness calvarial grafts in young children.

Sixteen patients (mean age, 1.9 years) underwent split-thickness calvarial bone grafting using a full-thickness craniotomy, high-speed drill, and osteotomes for bone harvesting. The minimal calvarial bone thickness for a successful graft was found to be 7 mm. All patients were diagnostically studied preoperatively with computed tomographic scans and skull films. The mean follow-up was 2.9 years (range, 0.75-7.9 years). All patients had successful graft take. There were no infections or mortalities. Continued graft growth was seen in all patients. There was one dural tear during harvesting with no cerebrospinal fluid leak or postoperative sequelae. This analysis indicates that split-thickness calvarial grafts can be safely and adequately performed in children as young as 13 months of age.     

Completely Regressed Primary Cutaneous Malignant Melanoma with Nodal and/or Visceral Metastases

Partial regression of primary cutaneous malignant melanoma is not uncommon, and may predict a higher likelihood of metastasis and decreased survival. Complete histologic regression of a primary cutaneous melanoma is a rarer occurrence of uncertain significance, with only 30 cases reported in the literature. Herein, we detail five additional cases of complete histologic regression of a primary cutaneous melanoma, which were discovered upon presentation with metastatic disease. A pigmented lesion, or its remnant, coupled with historical information was strongly suggestive of cutaneous malignant melanoma. However, histologic examination of the lesions in toto using multiple levels, and in some cases immunohistochemical stains, failed to reveal residual melanoma. Our cases are typified by the presence of metastasis of malignant melanoma to regional lymph nodes, with the absence other suspicious lesions or other malignancies. Through these instructive cases, the concept of completely regressed primary cutaneous melanoma is reviewed and the literature critically appraised. When considering a diagnosis of completely regressed primary cutaneous melanoma, it is important that the cases be well‐documented and biopsy‐proven. All patients with a diagnosis of metastatic melanoma with an occult primary lesion require a thorough and complete skin examination and consideration of completely regressed cutaneous melanoma within the differential.     

Craniofacial,limb, and abdominal anomalies in a distinct syndrome: Relation to the spectrum of Pfeiffer syndrome type 3

Presented are 2 patients with abnormal craniofacial region, limbs, and abdomen, features that may be consistent with Pfeiffer syndrome, type 3. Both patients had bicoronal and bisphenoidal synostosis, extreme exophthalmic midface hypoplasia, and hydrocephalus. The limbs had a fixed flexion deformity of the elbows with broad thumbs which were radiopalmarly deviated; the toes were broad with a varus deformity and syndactyly of toes 2–5. Both patients developed bowel obstruction secondary to midgut malrotation, and one of the patients had prune belly syndrome. Review of the literature disclosed an additional patient who, in retrospect, had Pfeiffer syndrome type 3 and midgut malrotation. These patients suggest that intestinal malrotation with or without prune belly syndrome may be a common component of this entity. © 1993 Wiley-Liss, Inc.