Core promoter elements can regulate transcription on a separate chromosome in trans

Transvection can cause the expression of a gene to be sensitive to the proximity of a homolog. It can account for many cases of intragenic complementation at the Drosophila yellow gene, where one mode of transvection involves the action of enhancers in trans on a promoter present on a separate chromosome. Our goal was to identify cis-acting elements that regulate the trans action of enhancers. Using gene replacement, we altered two core promoter elements at yellow and tested the resulting alleles for their ability to support transvection. We found that the TATA box and initiator element can regulate transvection.

Thoracic solitary fibrous tumor: clinical and pathological diversity

Fourteen cases (13 pleural and one intrapulmonary) of solitary fibrous tumors (SFTs) (the so-called fibrous mesothelioma) were studied. The lesions occurred more in females (nine cases) than males (five cases). The age of patients ranged from 44 to 73 years old (median 60 years). The tumors presented as cough with or without blood-tinged sputum, exertional dyspnea, chest pain, nausea, body weight loss, fever, or as asymptomatic masses detected by routine chest radiograph. Two patients with huge (tumor larger than 20 cm) malignant tumors had accompanying pleural effusion and one associated with hypoglycemia. Ten benign tumors measured 2-11 cm (median size 7 cm) while the remaining four histologically malignant ones measured 20-30 cm in size. All of them were well circumscribed and thinly encapsulated. Hemorrhage and necrosis were more frequently seen in the malignant tumors. Histologically, these lesions were characterized by 'patternless pattern' with occasional hemangiopericytic features (three cases). The tumor cells were all immunoreactive for vimentin, CD 34, and focally actin-positive in one case, but not for keratin, desmin, S-100 protein, carcinoembryonic antigen, alpha 1-ACT and F VIII-related antigen, supported a primitive mesenchymal origin. p53 protein was expressed in two of the malignant cases. Proliferating cell nuclear antigen stain was positive with 50 and 80% of the labeling index in the benign and malignant tumors, respectively, but retinoblastoma gene protein was negative in all tumors. This analysis confirmed the relationship between histological malignant SFTs and tumor size, cellularity, mitotic activity, necrosis and tumor suppressor gene expression. However, the clinical behavior was unpredictable. Complete respectability seemed to be the most important indicator of clinical outcome in the less aggressive tumors.

Oncocytic adenomatous hyperplasia of the lacrimal sac: a case report and review of the literature

Oncocytic tumors of the lacrimal sac are very rare, with only 21 cases documented in the world literature. The authors report a 75-year-old woman who sought treatment for recurrent dacryocystitis and a palpable mass in the left medial canthal area. The patient underwent surgery for removal of a suspected lacrimal sac cancer, but pathologic findings indicated benign oncocytic adenomatous hyperplasia. Complete removal of the tumor and long-term follow-up are necessary in patients with lacrimal sac oncocytic lesions. The authors discuss the characteristic features of ocular adnexal oncocytic lesions and review the literature.

Repeated lumbar sympathetic blockade for complex regional pain syndromes type I--a case report

The causal mechanisms of reflex sympathetic dystrophy are not limited purely to sympathetic hyperactivity, but sympathetic blockade and physical therapy are still the mainstays of current treatment modalities. We reported a case of reflex sympathetic dystrophy over the left lower leg, who was successfully treated with repeated lumbar sympathetic blocks and physical therapy.

Two modes of transvection: enhancer action in trans and bypass of a chromatin insulator in cis

Ed Lewis introduced the term "transvection" in 1954 to describe mechanisms that can cause the expression of a gene to be sensitive to the proximity of its homologue. Transvection since has been reported at an increasing number of loci in Drosophila, where homologous chromosomes are paired in somatic tissues, as well as at loci in other organisms. At the Drosophila yellow gene, transvection can explain intragenic complementation involving the yellow2 allele (y2). Here, transvection was proposed to occur by enhancers of one allele acting in trans on the promoter of a paired homologue. In this report, we describe two yellow alleles that strengthen this model and reveal an unexpected, second mechanism for transvection. Data suggest that, in addition to enhancer action in trans, transvection can occur by enhancer bypass of a chromatin insulator in cis. We propose that bypass results from the topology of paired genes. Finally, transvection at yellow can occur in genotypes not involving y2, implying that it is a feature of yellow itself and not an attribute of one particular allele.

Chondromyxoid fibroma of bone: a clinicopathologic review of 278 cases

In a study of the clinical, radiographic, and pathological features of chondromyxoid fibroma, the tumor was slightly more common in men, usually in the second decade of life. Almost half of the tumors involved the long bones, although the ilium and the small bones were also common sites. Roentgenograms showed a sharply marginated, lobulated, lucent defect in the metaphysis. The tumor involved the medullary bone in an eccentric fashion, and the cortex was thinned and expanded. Periosteal reaction and soft tissue extension were uncommon. Mineralization was identified in 13% of the lesions. Histologically, the tumors were almost always arranged in lobules, which were prominent (macrolobular) or somewhat indistinct (microlobular). The tumor cells were spindle-shaped or stellate and arranged in a myxoid matrix. Calcification was seen in more than one third of the cases but was rarely prominent. Hyaline cartilage and chondroblastoma-like areas were not uncommon. Approximately 18% of tumors showed bizarre nuclei. Permeation of bony trabeculae was uncommon. Treatment was conservative surgical removal; approximately one fourth of the patients had recurrence.

Halothane requirement--a comparison between laryngeal mask airway insertion and endotracheal tube intubation in pediatric patients

BACKGROUND

The present study was to determine the effective concentration of halothane for insertion of laryngeal mask airway (LMA) and for intubation of endotracheal tube (ETT) in pediatric patients.

METHODS

Forty-eight ASA class 1 patients, aged from 10 months to 6 years, scheduled for minor elective surgery were randomly assigned to two groups i.e., LMA and ETT. The concentration of halothane effective in fifty percent of patients (EC50) was determined by the up-and-down method (with 0.5% as a step size). After the predetermined concentration of halothane delivered from a calibrated vaporizer was established and maintained for 20 min, LMA insertion or ETT intubation was attempted without the patient being curarized. The response of patient to LMA or ETT was reported either as "movement" or "non-movement". The effective concentration and associated 95% confidence limits were determined in each group.

RESULTS

An effective concentration of halothane for LMA insertion was 1.5 +/- 0.4% (95% confidence limits 1.4-1.7%), whereas that for ETT intubation was 2.3 +/- 0.5% (95% confidence limits 2.1-2.5%). The difference between these two values was statistically significant (p < 0.01). Airway reflexes after LMA insertion were minimal.

CONCLUSIONS

The insertion of LMA could be performed at a significantly less halothane concentration in comparison with ETT intubation in children.

Sonography of pigmented villonodular synovitis in the ankle joint

Pigmented villonodular synovitis is a benign proliferative disorder of the synovium that results in villous nodule formation in joints, tendon sheaths, and bursae. We present a case of pigmented villonodular synovitis of the ankle joint that was diagnosed by sonography with color Doppler imaging. The sonograms revealed hypoechoic synovial proliferation, and hypervascularity was visible on color Doppler images. The differential diagnosis of a synovial thickening or mass is also discussed.

Relation between histological intensity of transforming growth factor-beta isoforms in human osteosarcoma and the rate of lung metastasis

Even though adjuvant chemotherapy has improved the 5-year survival rate of osteosarcoma patients, a significant percentage of patients eventually die from lung metastasis. Since transforming growth faCtor-beta (TGF-beta) has been demonstrated to be related to the tumor progression, we investigated the clinical implications of the presence of TGF-beta isoforms in 16 human osteosarcoma tissue. There were 10 males and 6 females with a mean age of 20.8 years of age (range, 8 to 57 years). Biopsied specimen before chemotherapy was fixed in 10% formalin, demineralized and followed by paraffin embedding. The locations of tumor included femur (10), tibia (3), humerus (1), fibula (1), and ilium (1). Histologic subtypes included osteoblastic (11), chondroblastic (2), and fibroblastic (3). All patients were followed for a minimum of 1 year (range 12 to 44 months) or to the development of lung metastasis. Five patients (31.3%) developed subsequent lung metastasis during the follow up. We used immunohistochemistry technique to investigate the presence of the TGF-beta isoforms in osteosarcoma tissue and its relationship to the subsequent pulmonary metastasis. The results showed the presence of one or more TGF-beta isoforms in tumor cells in osteosarcoma tissues (13 of 16, 81.3%) in all of the subtypes. However, minimal presence of TGF-beta isoforms was shown in the tumor bone matrix. The expression of TGF-beta1 or TGF-beta3 isoforms was associated with a higher rate of subsequent lung metastasis (p < 0.05, chi-square test). Further research is warranted to determine the utility of routine TGF-beta analysis in the clinical practice.

Nonspinal tuberculous osteomyelitis in children

Tuberculous osteomyelitis is uncommon in children but its incidence seems to have increased in our hospital recently. From April 1984 to December 1994, we treated 12 children with this problem. Three cases were diagnosed in the first 7 years and nine cases in the latter 4 years. Primary spinal lesion was excluded. There were seven boys and five girls, with an average age of 2.4 years (range 1-4.5). Anatomic sites of involvement were distal femur in three patients, proximal tibia in three, foot in three, proximal femur in one, proximal humerus in one, proximal radius in one, distal radius in one, and rib in one. Except for one case of hip lesion, the most common symptom was localized swelling. Delay in diagnosis was 6.6 months on average. The diagnosis was confirmed bacteriologically or histologically in all patients after surgical debridement and curettage. Anti-tuberculosis (TB) drugs were administered for 6 months postoperatively. All patients were followed-up for an average of 3.8 years (range 2-8) with satisfactory healing of their tuberculous lesions. Two cases were complicated with physeal bar formation. One patient had residual flexion contracture of the knee. Although the mortality from TB has decreased in Taiwan, the frequently reported late cases of TB deserve attention. Physicians should be aware that TB remains an important cause of bone lesions. These lesions can be healed by combined therapy with surgical debridement and anti-TB medication for 6 months.

Macrodactyly of the feet and hands

We reviewed the records of 16 patients with true macrodactyly and analyzed the typical clinical features and methods of treatment. Fourteen feet were involved in 13 patients (one was bilaterally affected). Three hands were involved in three patients. Clinically, all lesions in the hands and lesions in 11 of 14 feet involved the preaxial side. There was multiple digit involvement in two hands and 11 feet. Progressive macrodactyly (10 feet and two hands) was more common than the static type (four feet and one hand). Proximal involvement of the sole or palm occurred in seven feet and one hand; all cases were of progressive macrodactyly. Enlargement of the metatarsals or the metacarpals was frequent (11 feet and two hands). The growth behavior and extent of bony involvement were similar in patients with hand involvement and those with foot involvement. Fourteen patients had additional clinodactyly, either medial or lateral. The toes of eight feet had angular deformities in the sagittal plane; most were angulated dorsally. Nine patients underwent surgery and two had repeated surgery. The reduction procedures included debulking, ray resection, toe resection, phalangeal resection, and phalangeal epiphysiodesis; the corrective procedures included wedge osteotomy, interdigitalization, and split thickness skin graft. Of the nine patients surgically treated, five had good results and four had fair results. Of the seven patients without surgical repair, three had fair results and four had poor results. Surgical debulking, phalangeal resection, ray resection, and phalangeal epiphysiodesis produced significant improvement in macrodactyly of the feet and hands. Toe resection was not as beneficial.

[In vitro stimulation of HTC hepatoma cell growth by recombinant human augmenter of liver regeneration (ALR)]

It was demonstrated that biologically active ALR could be expressed from its cDNA in transient expression experiments in cos-7 cells. The results showed that the cytosolic fraction from the transfected cells with constructed plasmids DNA stimulated of DNA synthesis of in vitro HTC cells in a dose dependent manner. This finding suggests that the HTC hepatoma cell line may be used as a target for bioassay of human ALR in vitro.

[Increase in the level of augmenter of liver regeneration mRNA in the rat regenerating liver after partial hepatectomy]

Augmenter of liver regeneration (ALR) is a novel hepatic stimulator. After 70% of the rat liver was removed, ALR-like activity in the remnant liver began to increase within 24 h. In parallel with the activity, the ALR mRNA level in the remnant liver increased 12 h after the operation and reached a maximum in 24 h. These findings indicate that the liver itself produces ALR, which may be a hepatotropic factor acting as a trigger for liver regeneration.

Brachial plexus injury during surgery--report of two cases

Brachial plexus is the most commonly injured peripheral nerve by malposition during operation. We present two cases of transient brachial palsy after surgery under general anesthesia. Symptoms of the first case persisted about 60 min. Electromyography (EMG) and nerve conduction velocity (NCV) revealed no abnormal finding three days later. In the second case, axonal neuropathy was found at left axillary and suprascapular nerves by EMG and NCV three weeks later. Symptoms persisted for three months and had complete remission after conservative treatment.

Aplasia cutis congenita: report of one case

We present a female newborn with a skin defect on the vertex. Aplasia cutis congenita was diagnosed. No associated anomaly was found. There was no family or drug history noted. At one-year follow-up, the lesion tended to contract and became epithelialized. We report this case and also review the literature, and then we suggest a checklist for aplasia cutis congenita.

The lost endotracheal tube--a rare complication of accidental esophageal intubation

Endotracheal intubation is a discreet skill for the management of compromised airway. Various complications associated with this procedure have been described. Here, we would like to present a pediatric patient suffering from cerebellar atrophy, who was intubated in a local clinic due to seizure with cyanosis and loss of consciousness. Unfortunately, due to inadvertent esophageal intubation and bad management, the patient swallowed the endotracheal tube together with two detached loose teeth. This irrational and iatrogenic medical misconduct as exemplified in this accident calls forth the need of educating and disciplining the nonanesthetic physicians for acute management of airway, particularly of those who would likely come across difficult airway problems.

Early seizures after severe closed head injury

BACKGROUND

We studied the incidence and clinical significance of early post-traumatic seizures after severe closed head injury.

METHODS

This prospective study is based on clinical observation of 3340 adult patients with severe closed head injuries, each of them having a Glasgow Coma Scale (GCS) 3 to 8 after trauma. Anticonvulsant agents were not given to these patients unless there was evidence of seizure.

RESULTS

One hundred and twenty-one patients (3.6%) experienced seizures within 1 week after head injury; 42 of these (1.26% of the series) had seizures within 24 hours after trauma. The incidence of intracerebral parenchymal damage was found to be higher among those patients who developed seizures in the first week (66.1%) than in those who did not (62.7%). However this result did not reach statistical significance. The patients with early seizures had a lower mortality rate (p < 0.01). In patients who survived from the initial injury, the occurrence of early post-traumatic seizures did not appear to influence the neurological recovery at 6 months after injury.

CONCLUSION

Presence of intracerebral parenchymal damage on CT scan after severe closed head injury does not increase the risk of early post-traumatic seizures. With proper treatment, patients presenting with early seizures may have a lower mortality rate. However, the occurrence of early seizures does not influence the neurological recovery in patients who survive the initial severe closed head injury.

Neonatal tuberous sclerosis with cardiac rhabdomyomas presenting as fetal supraventricular tachycardia

A case of fetal tuberous sclerosis with multiple intracardiac rhabdomyomas exhibited persistent supraventricular tachycardia. The tachycardia was terminated by the use of cardiac version. The largest tumor almost occluded the right ventricular inlet portion. The obstruction was relieved after surgical removal of the largest tumor. No arrhythmia was noted after 3 months of follow-up.

Postirradiation laryngeal osteosarcoma: case report and literature review

BACKGROUND

Laryngeal sarcoma is a rare disease entity. In review of the literature, chondrosarcoma is the most common sarcoma, followed by fibrosarcoma. Osteosarcoma is very rare; there are only seven cases reported in the literature. Postirradiation sarcoma is a late complication of radiotherapy. Osteosarcoma is the most common type in this group. The larynx is often involved in the radiation field of treatment for head and neck malignancies. However, postirradiation laryngeal osteosarcoma has not yet been reported.

METHODS

We present a 56-year-old man who under went radiotherapy for nasopharyngeal carcinoma 32 years ago and later developed a laryngeal osteosarcoma.

RESULTS

The patient underwent total laryngectomy but died 1 year and 9 months later with locally extensive disease.

CONCLUSIONS

We report the first case of postirradiation laryngeal osteosarcoma. In addition to surgical treatment, adjunctive therapies should be considered for this group of patients.

Case report: agenesis of the right lung diagnosed by three-dimensional reconstruction of helical chest CT

Unilateral pulmonary agenesis is extremely rare and the diagnosis can be made by a number of conventional methods. We report two cases: a 16-day-old girl and a 14-year-old girl presenting with tachypnoea in whom three-dimensional reconstruction of helical chest computed tomography was used to demonstrate the complete absence of the carina, right main bronchus and right lung. To our knowledge, these are the first cases of right lung agenesis diagnosed by this method.

Making the framework try-in, altered-cast impression, and occlusal registration in one appointment

Making a bilateral distal extension removable partial denture usually requires multiple appointments for metal-framework try-in, altered cast impression, and occlusal registration. This article describes an altered cast impression procedure that uses the prefabricated impression trays and record base for obtaining the jaw relation record. This method allows the framework try-in, altered cast impression, and jaw relation record to be efficiently completed in a single appointment.