Evidence for somatostatin-like immunoreactivity in discrete cells of the anterior pituitary of camel (Camelus dromedarius)

Immunocytochemical methods were applied to camel pituitaries. ACTH, beta-lipotropin (LPH), LH beta, GH, TSH, and PRL immunoreactive cells were identified. They were located on different parts of anterior pituitary and had different organization and shape. In addition, somatostatin-like immunoreactivity was seen in cells situated at the top of pituitary cleft specially in a cone-shaped extension of the intermediate lobe. The role and the eventual origin of these cells have yet to be established and their occurrence related to age and life conditions.     

The effect of ethambutol on tubercle bacilli within cultured human macrophages

Ethambutol (EMB) generally is believed to be clinically mycobacteriostatic. This concept was reexamined in an in vitro model of human tuberculosis that has direct relevance to in vivo effects in human subjects. Cultured human monocyte-derived macrophages infected with virulent Erdman tubercle bacilli were treated with EMB, and the resulting antimycobacterial consequences were measured by counts of acid-fast bacilli and bacterial colony-forming units. When added immediately after infection of the macrophages, EMB inhibited and killed tubercle bacilli within the cells at the same concentrations as it did in bacteriologic culture medium. When added 2 days after infection, it first appeared to increase the viable bacillary count above control culture levels, then killed intramacrophage bacilli at lower concentrations than in bacteriologic culture medium. We speculate that this occurs because macrophages enhance EMB effectiveness by killing tubercle bacilli, which have defective cell walls due to the effects of the drug. The concentrations of EMB that proved mycobactericidal in human macrophages are readily achieved clinically. The purported lesser antituberculosis effectiveness of EMB when compared to other bactericidal agents may be due to its less direct and efficient mode of killing tubercle bacilli, and the necessity therefore, for stricter maintenance of effective drug concentrations in vivo.     

Pulmonary function after segmentectomy for small peripheral carcinoma of the lung.

OBJECTIVE: The aim of this study is to compare the pulmonary function after a segmentectomy with that after a lobectomy for small peripheral carcinoma of the lung. Patients And Methods: Between 1993 and 1996, segmentectomy and lobectomy were performed on 48 and 133 good-risk patients, respectively. Lymph node metastases were detected after the operation in 6 and 24 patients of the segmentectomy and lobectomy groups, respectively. For bias reduction in comparison with a nonrandomized control group, we paired 40 segmentectomy patients with 40 lobectomy patients using nearest available matching method on the estimated propensity score. RESULTS: Twelve months after the operation, the segmentectomy and lobectomy groups had forced vital capacities of 2.67 +/- 0.73 L (mean +/- standard deviation) and 2.57 +/- 0.59 L, which were calculated to be 94.9% +/- 10.6% and 91.0% +/- 13.2% of the preoperative values (P =.14), respectively. The segmentectomy and lobectomy groups had postoperative 1-second forced expiratory volumes of 1.99 +/- 0.63 L and 1.95 +/- 0.49 L, which were calculated to be 93.3% +/- 10.3% and 87.3% +/- 14.0% of the preoperative values, respectively (P =.03). The multiple linear regression analysis showed that the alternative of segmentectomy or lobectomy was not a determinant for postoperative forced vital capacity but did affect postoperative 1-second forced expiratory volume. CONCLUSION: Pulmonary function after a segmentectomy for a good-risk patient is slightly better than that after a lobectomy. However, segmentectomy should be still the surgical procedure for only poor-risk patients because of the difficulty in excluding patients with metastatic lymph nodes from the candidates for the procedure.     

Using static MLC fields to replace partial transmission cerrobend blocks in treatment planning of rectal carcinoma cases

A treatment planning technique has been developed for using static multileaf collimators to replace partial transmission blocks for treating rectal or cervix carcinoma. The static MLC fields were used to replace the partial transmission block of the anterior-posterior pelvis field for the so-called “thunderbird” technique. Treatment plans were developed and evaluated on a commercial three-dimensional treatment planning system (FOCUS, Computerized, Medical Systems, St. Louis, MO). The result of the treatment plan comparison indicates that the static MLC fields are capable of achieving the same target, inguinal and pelvic dose distribution as the partial transmission cerrobend blocked fields. The MLC fields are easy to modify particularly for the match line adjustments. In conclusion, it is efficient and effective to use static MLC fields to replace partial transmission blocks in the “thunderbird” technique for treating rectal or cervix carcinoma.     

Multiple chronic subdural hematoma in shaken-baby syndrome

We described a case of shaken-baby syndrome with multiple chronic subdural hematomas. A 10-month-old male baby was admitted to our hospital because of loss of consciousness and convulsions. CT scan revealed an acute subarachnoid hemorrhage extending into the interhemispheric fissure and supracerebellar space. The patient was treated conservatively, and discharged from the hospitaL Two months after ictus, a baby was admitted to our hospital with general fatigue. CT scan demonstrated multiple chronic subdural hematomas. Burr hole irrigation and drainage brought about complete disappearance of these lesions. Retrospectively, it was found that these multiple subdural hematomas were due to shaken-baby syndrome. Shaken-baby syndrome is a form of child abuse that can cause significant head injury, and subdural hematoma is the most common manifestation. It is well known that the outcome of shaken-baby syndrome is generally not good. It is important to suspect shaken-baby syndrome when a chronic subdural hematoma is seen in a baby.     

Developing measures of surgeons' equipoise to assess the feasibility of randomized controlled trials in vascular surgery

Background

Equipoise is defined medically as a state of genuine uncertainty about the relative benefits of alternative treatment options. This study investigated individual and collective equipoise among vascular surgeons for controversial clinical questions to assess the feasibility of conducting randomized controlled trials.

Methods

Vascular surgeons throughout Australia and New Zealand received a survey by mail.

Results

Vascular surgeons (n = 146, 77% response fraction) were able to quantify the strength of their treatment preferences and did so differentially between clinical scenarios using a simple scale. Almost one quarter (24%; 95% CI, 18%-32%) were completely undecided about whether carotid endarterectomy or carotid stenting was preferable to treat carotid stenosis in high-risk patients, indicating individual equipoise. In contrast, the vast majority of respondents (89%; 95% CI, 82%-93%) favored carotid endarterectomy over carotid stenting for average-risk patients, suggesting lack of community equipoise for this patient group. Similarly, there was lack of community equipoise for treatments for abdominal aortic aneurysm in high-risk patients with 88% (95% CI, 81%-92%) favoring a minimally invasive approach. Older respondents were consistently less willing to take part in randomized trials, with strength of treatment preference also independently predicting willingness to participate in 4 of 6 trials.

Conclusions

Individual and community equipoise can be measured in a representative sample of surgeons as part of the feasibility assessment for future randomized controlled trials.     

Relationship Between Diffusion-Weighted Magnetic Resonance Imaging and Histological Tumor Grading of Hepatocellular Carcinoma

Background

Intrahepatic and extrahepatic recurrence remains a significant problem for hepatocellular carcinoma (HCC). The aim of this study was to determine the usefulness of diffusion-weighted magnetic resonance imaging (DWI) for histological tumor grading and preoperative prediction of early HCC recurrence within 6 months of operation.

Methods

A total of 44 patients who had undergone hepatic resection for HCC (50 nodules) were reviewed retrospectively. DWI was performed within 30 days before hepatectomy, and apparent diffusion coefficients (ADCs) were measured using 2 methods: mean ADC and minimum-spot ADC. Relationships between ADCs and histological differentiation and between ADCs and early recurrence of HCC were analyzed.

Results

Mean ADC was significantly lower in poorly differentiated HCC (n = 18, 1.07 ± 0.15 × 10^?3 mm²/s) than in moderately differentiated HCC (n = 29, 1.29 ± 0.21 × 10^?3 mm²/s; P < .05). Minimum-spot ADC was significantly lower in poorly differentiated HCC (n = 18, 0.69 ± 0.19 × 10^?3 mm²/s) than in well-differentiated HCC (n = 3, 1.15 ± 0.10 × 10^?3 mm²; P < .01) or in moderately differentiated HCC (n = 29, 0.98 ± 0.18 × 10^?3 mm²/s; P < .0001). Of 34 patients who were able to be observed for >6 months after resection, 9 showed early recurrence. Minimum-spot ADC was significantly lower in patients with early recurrence (n = 9, 0.64 ± 0.24 × 10^?3 mm²/s) than in patients without early recurrence (n = 25, 0.88 ± 0.19 × 10^?3 mm²/s; P < .05). On multivariate analysis, minimum-spot ADC was a significant risk factor for early recurrence (P < .05).

Conclusion

Quantitative measurement of ADC of HCC with magnetic resonance diffusion weighted imaging is a promising functional imaging tool in the prediction of histological grade and early recurrence before treatment.     

Automated tube voltage adaptation in head and neck computed tomography between 120 and 100 kV: effects on image quality and radiation dose

Introduction

Low tube voltage allows for computed tomography (CT) imaging with increased iodine contrast at reduced radiation dose. We sought to evaluate the image quality and potential dose reduction using a combination of attenuation based tube current modulation (TCM) and automated tube voltage adaptation (TVA) between 100 and 120 kV in CT of the head and neck.

Methods

One hundred thirty consecutive patients with indication for head and neck CT were examined with a 128-slice system capable of TCM and TVA. Reference protocol was set at 120 kV. Tube voltage was reduced to 100 kV whenever proposed by automated analysis of the localizer. An additional small scan aligned to the jaw was performed at a fixed 120 kV setting. Image quality was assessed by two radiologists on a standardized Likert-scale and measurements of signal- (SNR) and contrast-to-noise ratio (CNR). Radiation dose was assessed as CTDI_vol.

Results

Diagnostic image quality was excellent in both groups and did not differ significantly (p?=?0.34). Image noise in the 100 kV data was increased and SNR decreased (17.8/9.6) in the jugular veins and the sternocleidomastoid muscle when compared to 120 kV (SNR 24.4/10.3), but not in fatty tissue and air. However, CNR did not differ statistically significant between 100 (23.5/14.4/9.4) and 120 kV data (24.2/15.3/8.6) while radiation dose was decreased by 7–8 %.

Conclusions

TVA between 100 and 120 kV in combination with TCM led to a radiation dose reduction compared to TCM alone, while keeping CNR constant though maintaining diagnostic image quality.     

Successful surgery for an acute type A aortic dissection following repair of a descending thoracic aortic aneurysm

Acute type A aortic dissection in the presence of a previously repaired atherosclerotic descending thoracic aortic aneurysm is rarely reported. We experienced a patient who underwent an ascending aortic replacement with reconstruction of the aortic arch 16 months after repair of a descending thoracic aortic aneurysm. We succeeded in the redo operation with comprehensive techniques involving selective cerebral perfusion, deep hypothermia, early antegrade systemic circulation for cerebral protection, and femoro-femoral bypass with occlusion of the descending aorta for lower systemic perfusion as well as renal perfusion. The patient recovered and is doing well one year after the redo operation.     

Cystic lesions of the pineal region – MRI and pathology

Pineal lesions are rare. Tumours in this location comprise 0.4–1 % of intracranial tumours. They grow mainly as solid-mass lesions, and cystic tumours are not common. On MRI, a cystic configuration is associated usually with non-neoplastic pineal lesions rather than with a tumour, but analysis does not allow cystic pineal tumours to be distinguished from glial cysts with certainty. We compared neuroradiological and pathological data from 13 cystic pineal lesions, analysing preoperative MRI. Formalin-fixed, paraffin-embedded surgical specimens were stained routinely and immunocytochemically, using the streptavidin-biotin-complex method. Histology revealed six pineocytomas, four glial cysts, an arachnoid cyst, a low-grade astrocytoma and a teratoma. Signal characteristics of pineocytomas were similar in many respects to those of glial pineal cysts. Histomorphological analysis allowed unambiguous discrimination between pineocytomas and glial pineal cysts. Received: 19 July 1999/Accepted: 3 September 1999