The effect on the middle-ear cavity of an absorbable gelatine sponge alone and with corticosteroids

The objectives of this study were to establish whether there is an obvious difference between intact mucosa and abraded mucosa of the middle-ear cavity in respect to the potential side effects from the application of absorbable gelatine sponge (Gelfoam) and to investigate if Gelfoam combined with corticosteroid ointment (cortimycine, sterile 1% hydrocortisone acetate) can reduce the occurrence of these effects. Twenty Albino rats were used in the study. These animals were divided into four groups, with ten ears in each group. In group A, the middle-ear mucosa was kept intact, and Gelfoam was inserted into the middle-ear cavity. In group B, the middle-ear mucosa was abraded, and Gelfoam was inserted. In group C, Gelfoam with corticosteroid was implanted over the intact mucosa, and in group D, the mucosa was abraded prior to the insertion of Gelfoam with corticosteroid. The changes were evaluated 8 weeks postoperatively. In group A, there was a minimal increase in fibroblastic activity, vascular proliferation with mild to moderate fibrosis and all but two tympanic membranes were perfectly normal. However, in group B, we encountered a significant increase in fibroblastic activity, vascular proliferation and fibrosis, and we observed that all tympanic membranes were moderately to severely thickened. These histopathologic changes related to Gelfoam were noted to be decreased in group C and especially in group D. As previously reported in the literature, Gelfoam was found to promote the formation of connective tissue in the middle-ear cavity regardless of the status of the mucosa. The unwanted effects of this material may be decreased if it is combined with corticosteroids in the middle-ear cavity.     

Is regional tonometry a reliable index of tissue oxygenation? A comparative study with conventional global monitoring

This study was carried out on 30 critically ill patients admitted to the ICU of Farwania Hospital (Kuwait). All patients had clinical evidence of organ dysfunction or impending multiple organ failure. The severity of their pathology on admission was assessed according to the APACHE II score. The study of each patient began after inserting the pulmonary artery catheter. The prospectively defined end-point of the study was the removal of the pulmonary artery catheter (72 hours) or death of the patient with the catheter in situ. The aim of the study was to determine the sensitivity and specificity of the intra-gastric mucosal pH (pHi) and other derived data in assessing the adequacy of tissue oxygenation, guiding therapy and prediction outcome. The results showed that pHi, pHa-Hi and PaCO2-PO2regional (reg) gradients were the most sensitive indices of tissue oxygenation and predictors of outcome. The mortality rate increased when pHi, PaCO2-PCO2reg and pHa-pHi gradients were < 7.3, > 10 mm Hg and < 0.2 respectively. The derived variables obtained by invasive monitoring like base deficit (BD), lactate concentration in mixed venous blood (Lmv) and oxygn uptake index (O2 UI) were valuable adjunct indices of tissue oxygenation. The risk ofmortality increased whten the BD was > -5.5 +/- 1.2 meq.L-1, Lmv was > 4.5 +/- 1.2 mmol.L-1, and O2UI was < 100 +/- 6 ml.min-1.m-2. We recommend the use of gastric tonometry in routine ICU clinical practice.     

The potential palliative role and possible immune modulatory effects of low-dose total body irradiation in relapsed or chemo-resistant non-Hodgkin's lymphoma.

In a group of 35 patients with relapsed and/or chemo-resistant non-Hodgkin's lymphoma (NHL), low-dose total body irradiation (LTBI) (+involved-field radiotherapy to bulky sites) achieved a complete remission rate of 29%, 2-years progression-free survival of 32% and a median progression-free survival of 12 months. The 2-year survival was 42% and the median survival was 17 months. Immuno-staining and flow cytometry of peripheral blood in 14 patients showed that LTBI leads to a significant increase in the percentage of CD4+ cells with a consequent significant increase in the CD4+/CD8+ ratio. High lymphocytic percent and a high percentage of CD4+ cells before LTBI were significantly correlated with longer response duration and overall survival. These data may suggest that the palliative potential of LTBI should be investigated as an alternative to chemotherapy in NHL patients. The pre-treatment percentage of lymphocytes and CD4+ cells may be used as predictors for response to LTBI.     

维吾尔药孜尔克中总黄酮、微量元素及脂肪含量的测定

目的:对维吾尔医药孜尔克中总黄酮、微量元素及脂肪含量进行测定。方法:采用分光光度法,测定孜尔克的根和果实中总黄酮的含量。采用索氏抽提法提取并测定孜尔克的根和果实的脂肪含量。用原子吸收分光光度法测定孜尔克中根和果实中钙、铁、钠、钾、铜、锌、锰7种微量元素。结果:总黄酮在0.006~0.06mg.ml-1之间与吸光度有良好的线性关系。回归方程:C=0.0732A-0.002267(mg.ml-1)。相关系数R2=0.9916。元素测定中钙、铁含量较高。结论:本法操作简便,快速,为进一步研究和综合开发利用这一民族药材提供了依据。     

Distribution of protein kinase Mzeta and the complete protein kinase C isoform family in rat brain

Protein kinase C (PKC) is a multigene family of at least ten isoforms, nine of which are expressed in brain (alpha, betaI, betaII, gamma, delta, straightepsilon, eta, zeta, iota/lambda). Our previous studies have shown that many of these PKCs participate in synaptic plasticity in the CA1 region of the hippocampus. Multiple isoforms are transiently activated in the induction phase of long-term potentiation (LTP). In contrast, a single species, zeta, is persistently activated during the maintenance phase of LTP through the formation of an independent, constitutively active catalytic domain, protein kinase Mzeta (PKMzeta). In this study, we used immunoblot and immunocytochemical techniques with isoform-specific antisera to examine the distribution of the complete family of PKC isozymes and PKMzeta in rat brain. Each form of PKC showed a widespread distribution in the brain with a distinct regional pattern of high and low levels of expression. PKMzeta, the predominant form of PKM in brain, had high levels in hippocampus, frontal and occipital cortex, striatum, and hypothalamus. In the hippocampus, each isoform was expressed in a characteristic pattern, with zeta prominent in the CA1 stratum radiatum. These results suggest that the compartmentalization of PKC isoforms in neurons may contribute to their function, with the location of PKMzeta prominent in areas notable for long-term synaptic plasticity.     

Tympanometric changes in an experimental myringosclerosis model after myringotomy.

HYPOTHESIS: The goal of this experimental study was to investigate the specific effect of myringosclerosis on tympanograms in the tympanic membranes of myringotomized rats by using otomicroscopy, tympanometry, and histopathology. BACKGROUND: Myringosclerosis is a common sequela of ventilation tube treatment of otitis media with effusion. The condition involves the hyalinization and calcification of the collagen layer in certain areas of the tympanic membrane. Previous animal experiments suggest an intimate relationship between the formation of myringosclerosis and an increased oxygen concentration in the environment of the wound after myringotomy. The result of a myringotomy therefore is an increased production of free oxygen radicals, initiating irreversible tissue damage involving fibrosis, hyalin degeneration, and finally apoptosis as observed in myringosclerosis. We propose an experimental model specific for creating sclerotic plaques solely on the tympanic membrane and for performing tympanometric measurements on this pure myringosclerosis model without creating any abnormality in the middle ear to test in what proportion myringosclerosis contributes to decrease of amplitude in tympanograms. METHODS: To assess the normal tympanometric values of Wistar albino rats, the pressure and peak admittance of the left middle ears were measured using a semiquantitative computerized clinical admittance meter using a sound frequency of 226 Hz. Twelve animals were randomly selected for the myringotomy group and perforations in the left ears were created. All tympanic membrane perforations in this group had healed and closed prior to the otomicroscopic examination and no pathologic reaction was observed in the external ear canals of rats. Otomicroscopic and tympanometric measurements were carried out on Day 15 and the degree of myringosclerosis was noted before the animals were killed. Twelve specimens in the myringotomy group were histopathologically examined for the presence of myringosclerotic plaques. RESULTS: Under light microscopy, extensive sclerotic lesions were found in the tympanic membranes of the myringotomy group, and these sclerotic deposits were located in the lamina propria. The myringosclerosis occurred predominantly adjacent to the handle of the malleus, but also near the annular region. In all ears with myringosclerosis, the magnitude of the maximum admittance reduced to approximately 50% of the Day-0 values, and this reduction was statistically significant (Z=-3.061, p=0.002). CONCLUSION: The present findings in this study are consistent with the fact that the movement of the tympanic membrane is hampered by lesions of sclerotic material, resulting in a decrease of amplitude in tympanograms (such as Type As) without any effusion or inflammation in the middle ear.     

Clinical results of free vascularized fibula graft in the management of precollapse osteonecrosis of the femoral head: A retrospective clinical study

Objective:This study aimed to evaluate clinical results, femoral head survival, and the need for total hip arthroplasty (THA) in patients with precollapse osteonecrosis of the femoral head (OFH) (Steinberg stage II and III) treated by free vascularized fibula graft (FVFG) application.Methods:We retrospectively reviewed 54 hips of 47 patients (39 males, eight females; mean age 36 ± 14 years) who underwent FVFG due to OFH, with at least two years of follow-up. The patient data, including Harris Hip Score (HHS), Visual Analogue Scale (VAS), and conversion to THA, were documented.Results:The right hip of 26 patients and the left hip of 28 patients were involved. Bilateral FVFG surgery was performed on seven patients due to bilateral OFH. The mean follow-up time was 5.5 (range 2-14) years. Survival of the femoral head was observed in 39 hips (72.2%), while the femoral head collapse was observed in 15 femoral heads (27.8%). The mean preoperative HHS increased from 46.5 (range = 12-85) to 86.5 (range = 33-100) postoperatively (P < 0.001). The mean preoperative VAS score improved from 8.2 (range = 2-10) to 1.3 (range = 0-10) postoperatively (P < 0.001). THA was performed on seven hips at a mean follow-up time of 1.8 years (range = 0.7–3.3). There was no significant difference in the collapse rate between unilateral or bilateral OFH (P = 0.175). A higher survival rate was observed in the Steinberg stage II femoral head patients compared to the stage III femoral head (P = 0.021).Conclusion:This study has shown that FVFG surgery can be a good option for managing patients with Steinberg stage II and III precollapse OFH to prevent femoral head collapse and joint function.     

Training generative adversarial networks for optical property mapping using synthetic image data

We demonstrate the training of a generative adversarial network (GAN) for the prediction of optical property maps (scattering and absorption) using spatial frequency domain imaging (SFDI) image data sets that are generated synthetically with a free open-source 3D modelling and rendering software, Blender. The flexibility of Blender is exploited to simulate 5 models with real-life relevance to clinical SFDI of diseased tissue: flat samples containing a single material, flat samples containing 2 materials, flat samples containing 3 materials, flat samples with spheroidal tumours and cylindrical samples with spheroidal tumours. The last case is particularly relevant as it represents wide-field imaging inside a tubular organ e.g. the gastro-intestinal tract. In all 5 scenarios we show the GAN provides an accurate reconstruction of the optical properties from single SFDI images with a mean normalised error ranging from 1.0-1.2% for absorption and 1.1%-1.2% for scattering, resulting in visually improved contrast for tumour spheroid structures. This compares favourably with the ∼10% absorption error and ∼10% scattering error achieved using GANs on experimental SFDI data. Next, we perform a bi-directional cross-validation of our synthetically-trained GAN, retrained with 90% synthetic and 10% experimental data to encourage domain transfer, with a GAN trained fully on experimental data and observe visually accurate results with an error of 6.3%-10.3% for absorption and 6.6%-11.9% for scattering. Our synthetically trained GAN is therefore highly relevant to real experimental samples but provides the significant added benefits of large training datasets, perfect ground-truths and the ability to test realistic imaging geometries, e.g. inside cylinders, for which no conventional single-shot demodulation algorithms exist. In the future, we expect that the application of techniques such as domain adaptation or training on hybrid real-synthetic datasets will create a powerful tool for fast, accurate production of optical property maps for real clinical imaging systems.