个性化颅骨成形术中植入材料类型与颅骨缺损面积的关系

目的：分析个性化颅骨成形术中,植入材料类型与颅骨缺损面积的关系。 方法：选择解放军总医院第二附属医院神经外科2002-03/2005-01和河北省三河市医院神经外科2003-09/2005-04收治的资料齐全的计算机辅助设计颅骨成形术患者75例,分为嵌入性材料（骨水泥、硅橡胶）组40例,根据颅骨缺损面积又分为大面积（≥36cm2）组17例和小面积（〈36cm2）组23例;覆盖性材料（钛网）组35例,大面积组14例和小面积组21例。采用头颅CT超薄扫描（层厚1.5mm）,三维重建,模拟缺损颅骨补片,应用激光快速成形技术,制作缺损颅骨及颅骨补片模型,患者认可后,根据患者的病情应用硅橡胶、骨水泥、钛网作为植入材料,进行手术植入。术后1周观察并发症：头痛、积液、松动。 结果：75例患者的补片与颅骨完整适配,塑形满意,术中无需修整,平均手术时间45min,83%（63/75）患者感到基本或完全恢复了原有容貌。手术并发症：嵌入性材料组头痛4例,积液10例,松动2例,共16例,其中大面积组13例,小面积组3例;覆盖性材料组头痛1例,积液2例,松动0例,共3例次,其中大面积组2例,小面积组1例。应用精确概率分析,两材料组之间手术并发症差异显著,两材料组颅骨缺损面积之间手术并发症差异显著,嵌入性材料大面积组与覆盖性材料大面积组之间手术并发症差异显著,嵌入性材料小面积组与覆盖性材料小面积组之间手术并发症无显著性差异。 结论：个性化设计的颅骨修补材料,能够最大限度的恢复患者外形,缩短手术时间,大面积的颅骨缺损应用钛网修补,小面积的应用钛网和嵌入性材料修补。根据患者颅骨缺损面积,选择不同植入材料,可以提高手术疗效,减少术后并发症。     

The nature of the renal adaptation to chronic hypocapnia

Metabolic balance studies were carried out in normal dogs to define the renal mechanisms responsible for the adaptation to, and recovery from, chronic hypocapnia. A chronic reduction in arterial CO(2) tension (Pa(CO2)) of some 15 mm Hg was achieved by means of chronic exposure of the animals to 9% oxygen in an environmental chamber. The development of hypocapnia was associated with a marked suppression of net acid excretion which, together with a slight accumulation of organic acids, produced a reduction in plasma bicarbonate concentration (8 mEq/liter) that led to nearly full protection of extracellular pH (DeltaH(+) = - 2.5 nmoles/liter). When Pa(CO2) was returned to control levels, an augmentation of acid excretion restored plasma composition to normal after a brief period of "posthypocapneic metabolic acidosis."The changes in renal acid excretion during both adaptation and recovery were accomplished in a fashion notably different from that previously observed in chronic hypercapnia, being linked to changes in cation rather than chloride excretion. Thus, in dogs ingesting a normal NaCl diet, suppression of hydrogen ion excretion during adaptation to hypocapnia was associated with an increased excretion of sodium rather than with a retention of chloride. The fact that this loss of sodium occurred without a concomitant loss of potassium strongly suggests that the hypocapneic state specifically depressed distal sodium reabsorption; if distal sodium reabsorption had not been depressed, a reduction in proximal sodium reabsorption or a diminution in distal hydrogen ion secretion (or both) should have produced an increase in potassium excretion.The interpretation that chronic hypocapnia diminished sodium reabsorption was supported by the finding that when renal sodium avidity was enhanced by restriction of sodium intake, acid retention was accomplished by a loss of potassium rather than of sodium. The accompanying reduction in plasma bicarbonate concentration was slightly less than that observed in dogs ingesting a normal NaCl diet, a finding probably accounted for by a slight difference in the availability of cation for excretion under the two experimental circumstances. These findings, taken together with the observation that augmented acid excretion during recovery from hypocapnia is linked to cation retention, suggest that an adequate intake of cation during both adaptation and recovery from chronic hypocapnia may be critical to the physiologic regulation of acid-base equilibrium.     

Direct quantitation of IgG subclasses 1, 2, and 3 bound to red cells by Rh1 (D) antibodies

The authors developed quantitative radioimmunoassays to allow direct measurement of total human IgG and individual IgG subclasses among antibodies bound to cell surfaces. The assays use four mouse monoclonal radioiodinated antibodies, one that reacts equally well with all four human IgG subclasses and three that are specific for human IgG subclasses 1, 2, or 3. The assays were used to analyze IgG subclass composition in 21 high-titer anti-D samples from Rh-negative volunteers immunized for Rh immunoglobulin production. Anti-D activity was restricted primarily to the IgG1 and IgG3 subclasses. Eleven of 21 sera demonstrated red cell antibodies with a marked predominance of IgG1 (87 +/- 3.6% of total IgG antibody, +/- SEM) and low levels of IgG3 (1.4 +/- 0.73%). In the remaining 10 sera, IgG3 made up a greater proportion of total IgG antibody (32 +/- 3.8%), although IgG1 was still predominant (61 +/- 4.1%). This observed dichotomy in the IgG subclass profiles of different anti-D sera may be a consideration in the selection of anti-D sera for the production of the immunoglobulin used in the prophylaxis of Rh-incompatible pregnancies.     

Characterization of deletions at 9p affecting the candidate regions for sex reversal and deletion 9p syndrome by MLPA

The distal region on the short arm of chromosome 9 is of special interest for scientists interested in sex development as well as in the clinical phenotype of patients with the 9p deletion syndrome, characterized by mental retardation, trigonocephaly and other dysmorphic features. Specific genes responsible for different aspects of the phenotype have not been identified. Distal 9p deletions have also been reported in patients with 46,XY sex reversal, with or without 9p deletion syndrome. Within this region the strongest candidates for the gonadal dysgenesis phenotype are the DMRT genes; however, the genetic mechanism is not clear yet. Multiple ligation-dependent probe amplification represents a useful technique to evaluate submicroscopic interstitial or distal deletions that would help the definition of the minimal sex reversal region on 9p and could lead to the identification of gene(s) responsible of the 46,XY gonadal disorders of sex development (DSD). We designed a synthetic probe set that targets genes within the 9p23-9p24.3 region and analyzed a group of XY patients with impaired gonadal development. We characterized a deletion distal to the DMRT genes in a patient with isolated 46,XY gonadal DSD and narrowed down the breakpoint in a patient with a 46,XY del(9)(p23) karyotype with gonadal DSD and mild symptoms of 9p deletion syndrome. The results are compared with other patients described in the literature, and new aspects of sex reversal and the 9p deletion syndrome candidate regions are discussed.     

Mental status impairment in patients with West Haven grade zero hepatic encephalopathy: the role of HCV infection

Background In patients with cirrhosis, subclinical hepatic encephalopathy, which negatively affects the activity of daily living, is often unidentified. In a multicenter observational study, we investigated the possibility of detecting minimal neurological changes consistent with subclinical hepatic encephalopathy by using the Trail Making Test in a cohort of patients with liver cirrhosis at hospital admission. Methods Seventy-seven consecutive patients with liver cirrhosis were studied (mean age, 69.5 ± 9.1; 95% confidence interval, 67.5–71.6 years). In all patients, possible encephalopathy was investigated according to the West Haven criteria. All those free of any sign of encephalopathy (West Haven 0) were also studied by the Trail Making Test forms A and B. The Child-Pugh score was determined in all patients, and results were compared with the West Haven stage. Exclusion criteria were use of benzodiazepine, beta adrenergic blockers, alcohol, or antiepileptic drugs, or coexistence of depression, dementia, Parkinson's disease, or chronic or acute cerebral vasculopathy. Results Of the 77 patients, 44 (57.1%, 23 men and 21 women) had West Haven score 0, but among these, 26 (59.1%) were diagnosed with mental impairment likely linked to minimal hepatic encephalopathy. Severity of liver disease correlated with the presence of likely minimal hepatic encephalopathy, because the prevalence of abnormal Trail Making Test results increased from 22.2% in Child-Pugh A, to 63.4% and 74.0% in Child-Pugh B and C, respectively. Conclusions The investigation of patients with cirrhosis by the West Haven test is not sufficient to identify subclinical forms of encephalopathy. The Trail Making Test (a simple, inexpensive test) in our series evidenced poor psychometric performance in more than half of the patients who were free of manifest encephalopathy. Subclinical hepatic encephalopathy was present mostly in patients with HCV-related cirrhosis. Detecting minimal hepatic encephalopathy in patients with cirrhosis may help improve their quality of life.     

The radiologist’s role in managing paediatric liver transplantation: personal experience with 40 patients

PURPOSE: The aim of our study was to evaluate the radiologist's role in managing paediatric orthotopic liver transplantation (OLT) through a retrospective review of our experience in diagnosing and treating post-OLT complications. MATERIALS AND METHODS: Forty children (mean age 4.6 years) underwent 44 OLTs over 71 months. The follow-up period (mean 724 days) was divided into three phases: hospital stay, up to three months after discharge and subsequent period. The number and type of radiological examinations, radiologically detectable complications and interventional procedures were analysed. RESULTS: Most examinations were carried out with ultrasound (US) (859/931 of all radiological studies performed during the first two phases, 92.3%). Colour-Doppler US enabled early detection and treatment of all vascular complications (9/40, 22.5% of patients; 13 complications in nine patients, eight arterial and five portal complications; 1.4 for each patient with complications). Computed tomography (CT) or angiography was very rarely employed. US also detected biliary complications (11 patients, 27.5%: three cases of segmental ducts excluded from the anastomosis, four cases of stenosis of the biliodigestive anastomosis, one lithiasis, three stenoses associated with lithiasis), which were successfully managed in 75% of the cases treated with interventional radiology procedures (percutaneous bilioplasty and/or lithotripsy). At the time of writing this paper, the patient survival rate was 100%, and the organ survival rate was 91% (40/44). There were four re-transplantations: three due to hepatic artery thrombosis and one to biliary stenosis with lithiasis. CONCLUSIONS: The radiologist's role is fundamental for early sonographic diagnosis of post-OLT complications in children. Vascular complications are often associated in a single patient, and early treatment may improve the prognosis. Interventional radiology represents a safe and effective treatment for many biliary complications.     

Two cases of hemichorea-hemiballism with nonketotic hyperglycemia: a new point of view

Hemichorea-hemiballism (HCHB) is an usually continuous, nonpatterned, involuntary movement disorder caused by basal ganglia dysfunction, commonly due to a vascular lesion, described in nonketotic hyperglycemic patients. Particular computed tomography and magnetic resonance imaging findings have been described. The pathogenic mechanism of chorea arising during hyperglycemia and the nature of neuroimaging findings are unclear. In this paper we describe two elderly women with onset of HCHB during a hyperglycemic episode. The symptoms persisted in one of them after recovery of normal glycemia. The pathophysiological mechanism of the disease is discussed in the light of clinical and neuroradiological follow-up.     

Extending the duration of first-line chemotherapy in metastatic breast cancer: a perspective review

The treatment of metastatic breast cancer is mainly palliative, but optimal management might result in survival improvement as well. For this reason, many trials have attempted to optimize the therapeutic approach in this disease setting. Among the possible options, chemotherapy represents the backbone of the treatment and survival improvements that have been shown by the use of modern chemotherapeutic agents. Whereas the type of chemotherapy is generally dictated by patient characteristics and those of their disease, substantial controversy still remains on how long chemotherapy should be administered after disease control is achieved. In this review, we have analysed all available evidence on the duration of first-line chemotherapy in advanced breast cancer.