shukoor65/lab-rag-model huggingface dataset:
Middle ear adenoma: tumour of mixed mucinous and neuroendocrine differentiation. Two cases of progressive hearing loss due to middle ear tumours are described. The histological characteristics numbered intraluminal mucin production and neuroendocrine features, as shown by argyrophilia and ultrastructural demonstration of dense core granules. These tumours have been known by many different names, reflecting the controversies relating to their presumed histogenesis and differentiation. The currently preferred designation is middle ear adenoma, and these two cases provide further evidence for dual lines of differentiation.
Suture technique affects perianastomotic colonic crypt cell production and tumour formation. Suture line recurrence is an important cause of failure after potentially curative resection for colonic carcinoma. Our aim was to determine whether suture technique affected the incidence of perianastomotic tumours in experimentally induced colonic cancer. Sprague-Dawley rats were randomized into three groups. A 1 cm longitudinal colotomy was repaired with four interrupted 6/0 polypropylene monofilament sutures, using either a transmural technique (n = 18) or a seromuscular technique (n = 18). Control animals (n = 18) had a sham laparotomy. All animals received nine, weekly, subcutaneous injections of azoxymethane (total dose 90 mg/kg) starting 6 weeks after laparotomy. Surviving animals were killed 32 weeks after laparotomy. Five animals from each group were given intraperitoneal bromodeoxyuridine (100 mg/kg) 1 h before being killed. At death, perianastomotic tumours occurred more frequently in animals with transmural sutures than in either controls or those with seromuscular sutures. This difference was associated with a greater mucosal bromodeoxyuridine crypt cell labelling index in the transmural suture group. We conclude that a transmural anastomotic suture technique promotes the development of experimental perianastomotic colonic tumours.
Recurrent deletion in the human antithrombin III gene. Eight unrelated patients with recurrent thromboembolism, a family history of thrombosis, and plasma antithrombin III (ATIII) activity/antigen levels consistent with a diagnosis of heterozygous type I ATIII deficiency were studied by polymerase chain reaction/direct sequencing of ATIII gene exon-coding regions. Frameshift mutations of one base and two bases, respectively, were found to have occurred in two unrelated patients at the same GAG codon (Glu 245) within exon 4 of the ATIII gene. A literature search showed six further hitherto unrecognized deletion "hotspots" in four other human genes. These deletion-prone sites exhibited sufficient sequence homology with each other to derive a consensus sequence (T G A/G A/G G A/C), suggesting that deletion in human genes may not only be non-random but also sequence-directed.
Detection of polyadenylated RNA in hepatitis B virus-infected peripheral blood mononuclear cells by polymerase chain reaction. Polymerase chain reaction (PCR) with a reverse transcriptase step characterized a specific transcription activity in hepatitis B virus (HBV)-infected peripheral blood mononuclear cells (PBMC) in two patients (1 and 2) with chronic hepatitis positive for antibody to hepatitis B core antigen (HBc). Patient 1 was also coinfected with human hepatitis delta virus. A patient who cleared HBV replication after antiviral treatment with vidarabine served as negative control. HBV-specific RNA poly A sequences were detected by PCR in PBMC of patients 1 and 2 even without detectable HBV DNA (patient 2) as shown by dot blot and PCR assays. RNA sequences were found in both the nucleus and cytoplasm. The demonstration of HBV mRNA sequences within PBMC suggests the transcription of viral DNA, in agreement with the findings of HBV surface antigen in PBMC. The results in patient 1 demonstrated HBV mRNA sequences in leukocytes even without PCR-detectable HBV DNA sequences, likely due to ongoing hepatitis delta virus replication.
Gold weight lid load as a secondary procedure. This paper discusses the use of gold weight lid load as a secondary procedure. By using three representative patients, I emphasize the following points: First, the dominance of the eye must be determined so that postoperative changes in the eyelid height can be anticipated. Second, in order to obtain an accurate weight of the implant needed, the restrictive effect on the eyelid from the previous surgery (a tarsorrhaphy or an encircling band) must first be eliminated. Third, to ensure the best result and the patient's comfort, lacrimal function, Bell's phenomenon, and levator function must be assessed.
Effect of intracoronary diltiazem on infarct size and regional myocardial function in the ischemic reperfused canine heart This study was designed to investigate whether intracoronary diltiazem given before reperfusion could enhance myocardial salvage in the canine heart. Twenty-five dogs were subjected to 90 min of coronary occlusion followed by 4 h of reperfusion. The dogs were assigned to one of three experimental groups. The early diltiazem group received intracoronary diltiazem into the distal coronary bed at the onset of coronary occlusion and for 60 min after reperfusion. The late diltiazem group received the same amount of drug beginning 15 min before reperfusion and the control group received saline solution for 90 min of occlusion and 60 min of reperfusion. Infarct size expressed as a percent of the area at risk was significantly smaller in the early and late diltiazem groups (15.6 +/- 3.6% and 21.2 +/- 5.1%, respectively) than in the control group (49 +/- 4.6%) (p less than 0.05). Intracoronary diltiazem restored systolic function of the stunned, previously ischemic tissue to essentially normal preocclusion values. Segmental shortening after reperfusion averaged 21.6% in the early diltiazem group versus 0 +/- 1.7% and 7.3 +/- 4% for the control and late diltiazem groups, respectively (p less than 0.05). Low dose intracoronary diltiazem did not alter hemodynamic variables or myocardial blood flow but did improve segmental shortening 2 and 6 h after reperfusion. These data indicate that intracoronary diltiazem given during occlusion or just before reperfusion increases the salvage of myocardium compared with the salvage achieved by reperfusion alone. These results also suggest that intracoronary diltiazem given during the ischemic period enhances systolic contractile function of postischemic stunned myocardium.
Influence of the site of tumor growth on the capacity of a low tumorigenic line of Friend erythroleukemia cells to differentiate. Friend erythroleukemia cells (FLC) passaged in mice are highly tumorigenic and multiply extensively in the livers of suckling DBA/2 mice without differentiating. In contrast, in vitro passaged FLCs injected intravenously were of low tumorigenicity, multiplied to a limited extent in the livers of suckling mice, and underwent marked differentiation from the proerythroblast to the orthochromatic erythroblast stage in the liver. The presence of characteristic C-type virions budding from the cell surface in various stages of erythroid differentiation served as a marker of the injected FLCs. When the same in vitro passaged FLCs that differentiated in the liver were injected subcutaneously in suckling mice, they formed large subcutaneous tumors consisting of sheets of undifferentiated tumor cells. It is concluded that the tumorigenicity of FLCs depended on the site of tumor growth and that there is an inverse correlation between the tumorigenic capacity and the capacity to differentiate.
Gallstone fragmentation during biliary lithotripsy: effect of stone composition and structure. In vitro lithotripsy with the Siemens Lithostar was conducted on 36 radiolucent or minimally calcified gallstones housed in an anthropomorphic phantom. The ease and pattern of fragmentation were correlated with global composition for the entire stone, regional or microcomposition (determined by Fourier-transform infrared spectroscopy), and microstructure (determined by scanning electron microscopy). Stones made up of more than 62% cholesterol required 50% more shock waves to pulverize all fragments to 0.3 cm or less than did stones of less than 62% cholesterol (p less than .01). An inverse relationship was found between the number of shock waves needed for fragmentation and the cholesterol content (r = .77). Although a broad range of fragmentation responses occurred, little variation was seen in the ease of fragmentation within stone families. The majority of stones fractured along radially oriented cholesterol plates, but one third of stones treated showed initial chipping or flaking at the periphery before radial fracture. This type of peripheral erosion most often occurred in stones with peripheral pigment rims. These stones required more shock waves and lagged in pulverization compared with more homogeneous cholesterol stones. The efficiency of fragmentation during biliary lithotripsy correlates with the stones' global cholesterol content. A stone's architecture, as reflected by its regional composition and microstructure, partially predicts the mechanism of fragmentation. These in vitro data may be useful in further refining criteria for selecting patients and understanding the fragmentation process.
Prognostic value of raised prostatic acid phosphatase and negative skeletal scintigraphy in prostatic cancer. Of 438 consecutive cases of newly diagnosed prostate cancer, 178 (41%) had skeletal metastases (T0-4 M1) at the time of diagnosis according to skeletal scintigraphy; 139 men had serum prostatic acid phosphatase (PAP) greater than twice the upper limit of normal on 2 separate occasions at the time of diagnosis and 65% of them had metastases on bone scan. However, 49 men with normal bone scans were found to have similarly raised serum PAP. (Such patients are defined as having skeletal metastases in the current Medical Research Council immediate versus deferred orchiectomy study and stratified accordingly). The actuarial survival of this group was calculated by life table methods and was compared with that of 2 other subgroups: those patients having metastases demonstrated on bone scan, and those patients having both normal bone scans and normal serum PAP. The survival of the "metastatic by acid phosphatase" group was significantly better than that of the "metastatic by bone scan" group but did not differ from that of patients having both normal scans and PAP. For patients with no scintigraphic evidence of skeletal metastases at diagnosis, those with a raised PAP were at a significantly greater risk of scan conversion, although this was more powerfully predicted by high histological grade.
Proteinase trapping: screening for viral proteinase mutants by alpha complementation. Many virally encoded proteinases cleave themselves out of a polyprotein, with cleavage occurring usually at their own N terminus. This property was used to develop an in vivo screening system using the lacZ gene fragment of M13mp18. When a fusion protein of the alpha fragment of beta-galactosidase and an active 2A proteinase of human rhinovirus 2 was expressed, alpha complementation was not affected, as the 2A proteinase cleaved itself off the alpha fragment. However, fusion of an inactive 2A prevented alpha complementation, as the 2A polypeptide remained fused to the alpha fragment. After random mutation of the 2A gene by PCR amplification, mutants were screened; M13 phage defective in alpha complementation were obtained at an efficiency of 5% and were shown to contain mutated 2A genes. Intermolecular cleavage was then examined by expressing an alpha fragment-inactive proteinase fusion protein as substrate for an active 2A proteinase expressed from an M13 vector. alpha complementation indicated intermolecular processing of the 2A cleavage site on the alpha fragment-inactive proteinase fusion protein. This versatile system thus allows the high-density screening of both active and inactive proteinase mutants, cleaving either intramolecularly or intermolecularly, and should be applicable to other proteinases of high specificity.
Excimer laser ablation of fibrocartilage: an in vitro and in vivo study. To date, lasers have found only limited applications in orthopedics. We employed a 308 nm XeCl excimer laser for ablation of fibrocartilage, in order to investigate the feasibility of excimer laser assisted meniscectomy. Experiments were conducted both in vitro and in vivo. For the in vitro study, human menisci, obtained during surgery and autopsy, were irradiated via a 600 microns core fiber at radiant exposures ranging between 20 mj/mm2 and 80 mj/mm2, at 20 Hz. Ablation rate measurements and histological analysis of the samples were performed. The ablation rates were found to range from 3 microns/pulse to 100 microns/pulse depending on the radiant exposure and/or the applied pressure on the fiber delivery system. Thermographic analysis was also performed during pulsed excimer as well as CW Nd:Yag and CW CO2 laser irradiation. Temperatures were lower for excimer laser (Tmax less than 65 degrees) than CW ND: Yag (Tmax less than 210 degrees) or CW CO2 (Tmax less than 202 degrees) laser. For the in vitro study, medial meniscectomy was performed in 15 rabbits with the excimer laser and a CW Nd:Yag laser in the right and left knee respectively. Excimer laser irradiation was performed at 70 mj/mm2. Nd:Yag irradiation was performed via a 600 microns core fiber at power outputs between 20 to 40 W for 10 and 20 seconds duration. The healing response to injury was investigated by histological analysis of the menisci after 1 day, 1, 2, 4, and 8 weeks following the laser procedure. Excimer laser treated menisci showed less inflammatory reaction and noticeable repair with minimal inflammatory response.
The effect of intravesical bacillus Calmette-Guerin therapy on the upper urinary tract. A total of 66 patients with low grade, low stage transitional cell carcinoma of the bladder who were treated with intravesical bacillus Calmette-Guerin (BCG) underwent cystourethrography to detect vesicoureteral reflux. BCG was instilled weekly for 6 weeks and monthly thereafter for up to 24 months. Whenever vesicoureteral reflux was found or morphological abnormalities were detected on excretory urography (IVP) an isotope renal scan was performed to evaluate the relative renal function. Vesicoureteral reflux was found in 13 patients (19.7%): 10 had grades 1 and 2A, and 3 had grade 2B reflux. The number of BCG instillations ranged from 8 to 22. IVPs were normal in 11 patients. In 2 patients mild unilateral dilatation was present before BCG instillations, and this remained unchanged during and after therapy. None of the 13 patients with vesicoureteral reflux had IVP features suggestive of urinary tuberculosis. In 11 patients the refluxing renal systems had normal relative renal function (50 to 55%). Two patients had a decrease to 40% of the relative renal function with normal IVPs, suggesting a nonBCG related cause. We conclude that BCG therapy is safe in patients with minimal reflux.
Intraoperative evaluation of intestinal ischemia: a comparison of methods. Methods for evaluating intestinal ischemia include standard clinical criteria, Doppler ultrasonography, and intravenous fluorescein injection. Each has disadvantages, and a combination of methods is often used. The purpose of this study was to determine whether surface oximetry could be used to assess perfusion in an animal whose intestinal diameter approximates that of infants. Reversible arterial, venous, and arteriovenous occlusion was studied in rabbit intestines. After 6 to 8 hours of occlusion, intestinal vascularity was evaluated by the four methods listed. Doppler ultrasonography and surface oximetry were found to be unreliable tools for assessing perfusion in this animal model. We conclude that standard clinical criteria and fluorescein remain the standards for intraoperative evaluation of intestinal perfusion.
Clinical parameters predictive of malignancy of thyroid follicular neoplasms. Needle aspiration biopsy is commonly employed in the evaluation of thyroid nodules. Unfortunately, the cytologic finding of a "follicular neoplasm" does not distinguish between a thyroid adenoma and a follicular cancer. The purpose of this study was to identify clinical parameters that characterize patients with an increased risk of having a thyroid follicular cancer who preoperatively have a "follicular neoplasm" identified by needle aspiration biopsy. A total of 395 patients initially treated at Vancouver General Hospital and the British Columbia Cancer Agency between the years of 1965 and 1985 were identified and their data were entered into a computer database. Patients with thyroid adenomas were compared to patients with follicular cancer using the chi-square test and Student's t-test. Statistically significant parameters that distinguished patients at risk of having a thyroid cancer (p less than 0.05) included age greater than 50 years, nodule size greater than 3 cm, and a history of neck irradiation. Sex, family history of goiter or neoplasm, alcohol and tobacco use, and use of exogenous estrogen were not significant parameters. Patients can be identified preoperatively to be at an increased risk of having a follicular cancer and accordingly appropriate surgical resection can be planned.
Metabolic markers of stress-induced myocardial ischemia. The human heart in the fasting state extracts free fatty acids (FFA), glucose, lactate, pyruvate, and ketones from circulating blood. The utilization of FFA accounts for most of the oxygen consumed and energy produced at rest. Patients with angiographically demonstrable coronary artery disease and stable angina pectoris have a resting myocardial metabolism similar to that of normal individuals. During atrial pacing in normal persons, there is a significant enhancement of glucose uptake but that of FFA is unchanged, and the oxidation of carbohydrates accounts for more than 60% of the energy produced. In patients with stable angina, myocardial perfusion becomes regionally inadequate during stress. Despite the increase of myocardial glucose utilization, carbohydrate oxidation is negligible. Pyruvate will not be oxidized but in the presence of increased amounts of reduced coenzymes will be reduced to lactate. In addition, a greater amount of alanine will be released by the myocardium through the transamination of pyruvate, with a concomitantly greater uptake of glutamate that serves as the NH2 donor. In addition, glutamate may be used as an anaerobic fuel through conversion to succinate coupled with GTP formation. Although coronary hemodynamics, including myocardial perfusion, return to baseline within a few minutes after stress, a longer time course is needed for myocardial metabolism to become normal. In particular, myocardial utilization of exogenous glucose remains higher well after the normalization of hemodynamic parameters. This is more pronounced in postischemic myocardium, but it also occurs in nonischemic muscle, and glucose is presumably used for rebuilding glycogen stores that were depleted during ischemia.
Orthotopic liver transplantation for incurable alveolar echinococcosis of the liver: report of 17 cases. Between 1986 and 1989, orthotopic liver transplantations were performed in our unit for 17 patients with incurable alveolar echinococcosis. Ten patients had hilar involvement (group I), and seven patients had posterior localization (five of them had chronic Budd-Chiari syndrome) (group II). The delay between diagnosis and the orthotopic liver transplantation was more than 48 mo in group Ia (six patients), less than 24 mo in group Ib (four patients) and less than 48 mo in group II. Previous operations were more common in group Ia than in group Ib and II. Five patients have died-four in group I and one in group II. The actuarial survival rate at 15 mo was 75%. Early reoperations were frequent (69%), mainly caused by rebleeding. Bacterial and fungal infections occurred only in group Ia (four cases) and group II (three cases). In eight patients (palliative group), residual foci of infected nonhepatic tissue occurred after surgery. The titer of specific antibodies decreased during the first 3 mo in all the patients but one. In patients with radical liver transplantation, the complete disappearance of specific antibodies occurred within 2 yr in four cases. In the remaining five patients, specific antibodies remained detectable, but no evidence of recurrence has been obtained up to now. In the palliative group, a peak of specific IgM occurred at 3 mo; an increase of specific IgG was observed later. The growth of residual parasitic foci was relatively slow, and all these patients remained asymptomatic with a mean follow-up of 19 mo. We conclude that orthotopic liver transplantation is feasible in incurable alveolar echinococcosis and could be proposed without delay to patients with parasitic Budd-Chiari syndrome or complicated secondary biliary cirrhosis. In the other cases, the best time to perform an orthotopic liver transplantation is more difficult to determine. Nevertheless, in the perspective of an orthotopic liver transplantation, the management of these patients has to change, and repetitive laparotomies for palliative surgical procedures have to be replaced by interventional radiology.
Avoiding the blanket approach to insomnia. Targeted therapy for specific causes. A systematic approach to the common complaint of insomnia usually results in a specific clinical diagnosis with clear therapeutic implications. Use of effective treatment strategies tailored to the situation can make treating insomnia a gratifying experience instead of a frustrating one.
Transformation of T lymphocytes by the v-fos oncogene. Activation of T lymphocytes through the T cell antigen receptor has been shown to stimulate a rapid and transient accumulation of c-fos mRNA and protein. Transfection of a normal murine T lymphocyte clone with the FBJ-v-fos oncogene resulted in generation of a cell line that was morphologically transformed, had lost the requirement for IL-2 for proliferation, and was tumorigenic in adult syngeneic mice; however, the transformed cells retained the ability to proliferate in response to IL-2. The transformed cells did not show constitutive expression of IL-2 or c-fos mRNA, although the promoter regions of both IL-2 and c-fos genes contain AP-1 sites that are expected to be targets for binding of Fos/Jun complexes. In contrast, the transformed T cells showed increased constitutive expression of IL-2R alpha and c-myc mRNA; these genes may represent cellular targets for transformation by v-fos and physiologic activation by c-fos. We discuss the possibility that these transformed cells behave as cells partially activated through the TCR, and that transformation occurs through a mechanism independent of IL-2.