123rc/medical_text huggingface dataset:
Intraoperative peripheral Nd:YAG laser-assisted thermal balloon angioplasty: short-term and intermediate-term follow-up. Laser-assisted thermal balloon angioplasty was performed in 48 arteries (iliac, superficial femoral, and popliteal). Indications for surgery were limb salvage (25%), rest pain (38%), and claudication (38%). Patients were categorized into three groups: lesions less than 5 cm, greater than 5 to 10 cm, or greater than 10 cm in length. Demographic characteristics, risk factors, and outcome measures were compared by use of Fisher's exact test and Student's t test. The time for vascular patency failure was compared by use of a standard Kaplan-Meier survival analysis for the three groups. Initial failure to recanalize was noted in 14% in lesions less than 5 cm, 40% in lesions greater than 5 to 10 cm, and 73% in lesions greater than 10 cm. The overall success rate was 38%, with a mean follow up of 1 year. The less than 5 cm lesion group had a significantly higher rate of overall success (59%, p = 0.005) than the other two groups combined. The greater than 10 cm lesion group did significantly worse (9%) than the other two groups combined (p = 0.028). Patients in the less than 5 cm group had significantly longer patency than the other two groups (p less than 0.01). Iliac lesions had a higher overall success rate (73%) than superficial femoral and popliteal artery lesions (35%) (p = 0.038). In conclusion, the widespread application of laser-assisted thermal balloon angioplasty cannot be justified without further long-term clinical and laboratory investigation. Conversely, the potential of this technique should not be dismissed out of hand. Proper patient selection, length and nature of the lesion to be treated, and the appropriate forms, doses, and method of delivery of laser energy, remain to be defined.
Omeprazole in the management of intractable esophageal ulceration following injection sclerotherapy. Transient esophageal ulceration is a common finding after sclerotherapy of varices. A small proportion of these ulcers become chronic and resistant to conventional therapy. Such chronic ulcers have been associated with pain, stricture formation, and recurrent hemorrhage. The use of omeprazole, a proton pump inhibitor, was examined in the current study in the treatment of 10 patients (6 women, 4 men; age range, 27-86 years) with cirrhosis (PBC, 4; sclerosing cholangitis, 2; chronic active liver disease, 2; alcohol, 1; and cryptogenic, 1) who developed an esophageal ulcer after a mean of 13 (range, 8-21) sessions of sclerotherapy. The ulcers had been present for 3-54 months despite prolonged treatment with high-dose H2-receptor antagonists and sucralfate. In each case one or more complications had occurred: severe pain in 3, stricture formation in 4, and recurrent hemorrhage in 7 cases. After an 8-week course of omeprazole, 40 mg daily, endoscopy confirmed complete healing of the ulceration in all 10 cases with symptom resolution. In 2 cases the ulcer recurred, with associated bleeding within 6 weeks of discontinuing the treatment in 1 patient. Both cases responded to repeat therapy. These results confirm the efficacy of omeprazole for postsclerotherapy ulceration and imply that acid-pepsin has a role in perpetuating such ulcers.
Is sick sinus syndrome an adenosine-mediated disease? Effects of intravenous aminophylline on sick sinus node function after pharmacologic autonomic blockade. To assess the effects of intravenous aminophylline on the sinus node, 12 patients with clinical and Holter monitor-documented sick sinus syndrome were studied (1) during the control state, (2) after pharmacologic autonomic blockade and (3) 5 min after intravenous administration of aminophylline. The effects of aminophylline on sinus node function were compared with those after pharmacologic autonomic blockade. No significant improvement of sinus node function was found after intravenous aminophylline administration with a mean sinus cycle length and a mean maximum CSRT of 968 +/- 218 and 1832 +/- 1036 ms, respectively. The mean serum theophylline level was 10.9 +/- 1.7 micrograms/ml. Since aminophylline is an adenosine receptor antagonist, these findings suggest that intrinsic adenosine may not play an important role in pathogenesis in patients with chronic and advanced sick sinus syndrome.
Life events and difficulties preceding stroke. Life events and difficulties were recorded for the year before stroke, using a standardised semi-structured interview, in 113 surviving patients seen after their first ever in a lifetime stroke. An age and sex-matched control group (n = 109) was also interviewed about the preceding year. The stroke patients reported fewer non-threatening events and events with only a short-term threat, while difficulties were reported with equal frequency by the two groups. However, events which were severely threatening in the long-term were significantly more common in the stroke patients (in the 52 weeks before stroke 26% versus 13%, odds ratio 2.3, 95% confidence interval 1.1-4.9). The increased rate was apparent throughout the year and not just in the weeks immediately before stroke onset. The number of stroke patients experiencing severe events in the follow up year fell to the level found in the control group. Recognised risk factors for stroke were found equally in those patients with and without severe events before onset, except that hypertension was rather less common in the patients who had experienced a severe event. It therefore appears that severe life events may be one of the determinants of stroke onset.
Angioplasty of renal arteries: a report of ten year's experience. Report of PTA of renal arteries in 288 patients. Primary results show good to optimal dilatation of the arteries (60.6% to 78.6%). One third of all cases achieved optimal blood pressures. In about 40% antihypertensive drugs had to be administered, in about 30% blood pressure remained unchanged although PTA was effective. PTA of renal arteries is the best method of treating renal hypertension, also because of the low rate of complications.
Evaluation of metastatic cardiac calcification in a model of chronic primary hyperparathyroidism. Recent reports have fueled an interest in the prevalence and significance of metastatic calcium deposition in patients with chronic hyperparathyroidism. Experimental data are limited by the lack of suitable in vivo animal models. We have developed a model of marked hypercalcemia and overproduction of parathyroid hormone using somatic gene transfer. Briefly, the process involves infection of cultured rodent fibroblasts (RAT-1 cells) with a retroviral expression vector that contains the gene encoding human parathyroid hormone. Fibroblasts are grown to confluence on collagen-coated dextran microcarrier beads and are injected into the peritoneal cavities of syngeneic Fisher rats. Human parathyroid hormone production in rat serum is quantified by an immunoradiometric assay for human parathyroid hormone (1-84), which does not recognize rat parathyroid hormone. These rats consistently show production of human hormone within a week. Levels increase progressively, often to 1 ng/ml within 60 days of injection. Serum calcium showed a concomitant rise to an average of 15.5 mg/dl. In this study, 13 rats that had been transplanted with parathyroid hormone-producing fibroblasts were killed 80 days after injection. Examination of the skeleton revealed demineralization and histopathologic sequelae of parathyroid hormone excess with extensive osteoclastic bone resorption. Examination of the hearts revealed calcification in five of 13 hearts. There was no involvement of major coronary arteries or conducting systems, but there was calcification of cardiac myocytes, primarily in subepicardial region. This model may permit an understanding of the mechanisms for sudden cardiac death in severe hypercalcemia.
Variceal rebleeding after portosystemic shunting. Strategies and solutions to a vexing problem. The purpose of this review was to discuss an approach to the treatment of recurrent bleeding from esophageal or gastric varices after portosystemic shunt. From our own clinical experience, as well as that of others, it appears that re-establishment of portal decompression should offer the best chance at long-term survival. Luckily, innovations in angiographic technique have allowed attainment of this goal without the inordinate risk of an operative procedure. However, not all patients' situations will be amenable to such treatment. For some of them, operative decompression of the portal venous system can be carried out in an anatomic area previously untouched. For those patients in whom no decompression is possible, direct endoscopic treatment of the varices will offer an alternative, albeit temporizing, approach.
Potential complications of high-dose epinephrine therapy in patients resuscitated from cardiac arrest Adults resuscitated from nontraumatic cardiac arrest who received intravenous epinephrine in doses chosen by the treating physician and who survived at least 6 hours were studied to determine if high-dose epinephrine produced more complications than standard-dose. A total of 68 patients were enrolled and evaluated for postresuscitation complications attributable to epinephrine, using a two-tailed t test, and contingency analysis. The 33 patients receiving high-dose epinephrine and 35 patients receiving standard-dose epinephrine were similar in demographics and variables known to affect outcome. There was no difference in potential complications between groups except serum calcium, which was 1.97 mmol/L (SD, 0.20) in the high-dose epinephrine group and 2.10 (SD, 0.20) in the standard-dose group. Hospital discharge rates (18% in the high-dose vs 30% in the standard-dose group) and neurological status on discharge were not significantly different. High-dose epinephrine did not produce increased direct complications in this cardiac arrest population compared with standard-dose epinephrine.
Omeprazole in H2 receptor antagonist-resistant reflux esophagitis. We conducted a retrospective review of 25 patients with severe reflux esophagitis treated with omeprazole because of failure of H2 receptor antagonists to heal their esophagitis. Prior to beginning omeprazole (40 mg/day), all patients were on H2 antagonists for at least 9 months and still had endoscopic evidence of longitudinal (grade II) or circumferential (grade III) distal esophageal ulceration. Omeprazole therapy brought about complete endoscopic healing in 24 of 25 patients (96%). Twenty-three of 24 healed patients were then restarted on H2 antagonists as maintenance therapy. Repeat endoscopy was performed if symptoms recurred. Fourteen of 24 patients (58%) had recurrence of endoscopic esophagitis documented between 26 and 300 days from the time of starting maintenance therapy. Two of these 14 patients opted for antireflux surgery, whereas the remaining 12 were once again given omeprazole, which again resulted in symptom resolution in all patients. These data suggest that most patients with H2 receptor antagonist-resistant ulcerative esophagitis cannot be successfully maintained on H2 antagonists even after the ulcers have been healed with omeprazole. Further studies are required to determine the role of omeprazole compared to other treatments in the long-term maintenance therapy of these patients.
Transient myocardial ischemia and its relation to determinants of myocardial oxygen demand. Because of conflicting data and a clear need to establish the relative role of increase in myocardial oxygen demand versus reduction in coronary blood flow in the causation of transient ischemia, the role of heart rate and blood pressure changes immediately preceding and during the transient ischemic events observed during daily life were evaluated in 25 patients with coronary artery disease. Elevations in heart rate before onset of ischemia were observed in 61% of the episodes. Similarly, 73% of the ischemic events were preceded by an increase in arterial pressure. These data provide evidence for a significant role of increased myocardial oxygen demand in the genesis of transient myocardial ischemia.
Effect of ulcerative colitis and smoking on rectal blood flow. Rectal blood flow was measured by laser doppler flowmetry over 60 minutes in eight patients with colitis in remission and eight healthy male non-smokers. Ten smokers were also examined on two occasions, one of which included smoking a cigarette. Plasma nicotine concentrations were measured in smokers. All subjects showed a pronounced fall in rectal blood flow in the first 30 minutes and patients with colitis had significantly higher values compared with smokers (p less than 0.002; p less than 0.04) and non-smokers (p less than 0.007; p less than 0.002) during the first and second 30 minutes respectively. Values in smokers and non-smokers were similar, but smoking a cigarette was associated with a significant fall in blood flow (p less than 0.04) and this change was inversely related to the rise in plasma nicotine concentration (r = -0.63; p less than 0.05). The findings may be relevant to the association between colitis and the smoking history.
Cerebrospinal fluid dynamics in the tardive cauda equina syndrome of ankylosing spondylitis. Typical cauda equina syndrome secondary to long-standing ankylosing spondylitis is reported in a 63-year-old man. Radionuclide cisternography demonstrated a resorption defect of cerebrospinal fluid in the enlarged lumbosacral dural sac. After transient symptomatic improvement with acetazolamide, a lumboperitoneal shunt was placed. The rate of cerebrospinal fluid, isotope resorption became normal. In the 5 years of follow-up, partial remission has been observed.
Dementia, depression, or grief? The differential diagnosis. Depression, grief, and dementia are conditions frequently encountered among the community-living elderly. This review offers a primary care perspective of the distinguishing features for each and discusses the special issues of managing the elderly. Major depression in the elderly usually responds to antidepressant medication, whether the depression occurs alone (endogenous) or as a response to another condition (reactive).
Patient-controlled analgesic administration. A comparison of steady-state morphine infusions with bolus doses. The authors have shown previously that bone marrow transplant (BMT) patients who self-administered bolus doses of morphine gained equal oral mucositis pain relief while using less drug compared with similar patients receiving morphine by staff-controlled continuous infusion. In a follow-up study they compared the efficacy and side effects of morphine in two groups of marrow transplant patients who controlled their own analgesic administration either by conventional bolus-dose, patient-controlled analgesia (PCA) or by adjusting the rate of continuous morphine infusion to increase or decrease their plasma morphine concentration. Patients controlling their morphine infusion rates (pharmacokinetically based patient-controlled analgesia [PKPCA] group) obtained more relief from oral mucositis pain than did patients using conventional PCA. Patients in the PKPCA group used more morphine than PCA patients and achieved superior pain relief without significant increases in side effects (e.g., nausea, mood changes, sedation). The authors conclude that PKPCA improves the management of prolonged, severe pain in marrow transplant patients and that this approach to patient-controlled analgesia may be useful in other types of persistent pain.
Tumoral thrombosis of cerebral venous sinuses: preoperative diagnosis using magnetic resonance phase imaging. Intracranial, dural-based neoplasms will not infrequently invade adjacent venous sinuses. Therefore, the preoperative diagnosis of venous invasion is important, as it will alter the surgical approach to the lesion. Magnetic resonance imaging is a noninvasive means of visualizing the cerebral venous sinuses. The preoperative diagnosis of venous thrombosis can, however, be difficult and confusing with conventional spin-echo magnetic resonance imaging because of variable appearances produced by blood clot degradation products as well as flowing blood. Phase magnetic resonance imaging is a simple method that can be acquired simultaneously with conventional spin-echo sequences, and is based primarily on whether protons are stationary or moving. In the context of venous sinus occlusion, phase imaging can demonstrate the presence or absence of blood flow more easily than spin-echo imaging. Three cases of dural-based neoplasms are presented that demonstrate the utility of phase imaging in diagnosing tumoral occlusion of the venous sinuses.
Acute respiratory failure and pulmonary thrombosis in leukemic children. Acute respiratory failure (ARF) in an 11-year-old child with pre-T acute lymphoblastic leukemia (ALL) at the beginning of induction therapy was observed, connected with a pulmonary thrombosis and not with an infective origin. A systematic search for this pathology identified six other children with the same pulmonary complication, five of whom where in the early phase of acute nonlymphoblastic leukemia (ANLL) and one in induction therapy for ALL in marrow relapse. At the beginning of the symptomatology, all children presented severe hypoxia and hypercapnia, with no or minimal chest radiograph abnormalities and no clear hemodynamic involvement. In all patients the arteriography and nuclear imaging studies confirmed the diagnosis. The causes of the thrombi could be connected with neoplastic emboli after cell lysis and/or with the vascular damage resulting from antiblastic therapy. Intravenous urokinase treatment and respiratory assistance had been successfully carried out in six of seven children.
Pneumatic chest wall compression. A cause of respiratory failure from massive subcutaneous emphysema. Subcutaneous emphysema rarely causes significant adverse clinical consequences. Two patients had development of massive subcutaneous emphysema during positive-pressure ventilation that resulted in chest wall compression and respiratory failure. Drainage of the subcutaneous air produced dramatic improvement. Subcutaneous emphysema is potentially fatal in ventilated patients. Specific decompression of subcutaneous tissues is indicated in such extreme cases.
Tumor factors predicting for prognosis in metastatic breast cancer. The presence of P24 predicts for response to treatment and duration of survival. Fifty-one patients with metastatic breast cancer were investigated to determine tumor parameters with prognostic significance. Investigations included determinations of P24 content by immunocytochemical means using a monoclonal antibody to P24 protein; immunocytochemical analysis of estrogen and progesterone receptors; ploidy analysis by flow cytometry, and histologic grading. There were significant correlations between the presence of P24 and estrogen receptor, between histologic grade and P24 expression, and between estrogen and progesterone receptors. Of the tumor factors investigated only P24 protein was, however, of prognostic significance. Patients with P24-positive tumors had a significantly higher rate of response to treatment as well as more prolonged duration of response and duration of survival from diagnosis of metastatic disease. None of the other variables investigated were significantly predictive of outcome. P24 protein may be a useful predictor of prognosis in metastatic breast cancer.
Sympathetic neural contribution to salt-induced hypertension in Dahl rats. The Dahl strain provides a model for examining mechanisms involved in the genetic sensitivity or resistance to salt-induced hypertension. Dahl salt-sensitive rats develop hypertension when fed a high salt diet; Dahl salt-resistant rats remain normotensive. Based on early experiments, it was thought that hypertension in Dahl salt-sensitive rats epitomized the overriding importance of renal and humoral mechanisms in salt-induced hypertension, but studies in the past 15 years have demonstrated that alterations in sympathetic neural mechanisms also participate critically in the genetic predisposition to salt-induced hypertension in Dahl salt-sensitive rats. This article briefly reviews sympathetic neural mechanisms in Dahl rats, including evidence for a role of afferent baroreceptor as well as central neural and peripheral adrenergic mechanisms in salt-induced hypertension in Dahl salt-sensitive rats.
Drug-induced DNA damage and tumor chemosensitivity. Cytotoxic drugs act principally by damaging tumor-cell DNA. Quantitative analysis of this interaction provides a basis for understanding the biology of therapeutic cell kill as well as a rational strategy for optimizing and predicting tumor response. Recent advances have made it possible to correlate assayed DNA lesions with cytotoxicity in tumor cell lines, in animal models, and in patients with malignant disease. In addition, many of the complex interrelationships between DNA damage, DNA repair, and alterations of gene expression in response to DNA damage have been defined. Techniques for modulating DNA damage and cytotoxicity using schedule-specific cytotoxic combinations, DNA repair inhibitors, cell-cycle manipulations, and adjunctive noncytotoxic drug therapy are being developed, and critical therapeutic targets have been identified within tumor-cell subpopulations and genomic DNA alike. Most importantly, methods for predicting clinical response to cytotoxic therapy using both in vitro markers of tumor-cell sensitivity and in vivo measurements of drug-induced DNA damage are now becoming a reality. These advances can be expected to provide a strong foundation for the development of innovative cytotoxic drug strategies over the next decade.
Computed tomographic density of metastatic lymph nodes as a treatment-related prognostic factor in advanced head and neck cancer. Pretherapeutic identification of patients likely to benefit from neoadjuvant chemotherapy for head and neck epidermoid cancer is of interest. We retrospectively analyzed the pretherapeutic computed tomographic (CT) scans of lymph nodes of 70 patients with head and neck cancer. All 70 patients were clinically classified as having stage IV disease. The purpose of our analysis was to compare the prognostic value of CT node density with that of the following factors: age, T and N categories, Eastern Cooperative Oncology Group performance status, tumor site, histopathologic type of disease [squamous cell carcinoma (SCC) or undifferentiated carcinoma of nasopharyngeal type (UNCT)], and type of local-regional treatment. A simple two-grade nodal density grading system was devised. The density of normal adjacent muscle was chosen as the density standard. A node was classified grade 1 if less than 33% of the node consisted of hypodense zones. A node was classified grade 2 if more than 33% of the node consisted of hypodense zones. Patients with grade 1 nodes had a complete response rate of 68% (21/31) compared with 8% (3/39) for those with grade 2 nodes (P less than .0001). The only other factor associated with complete node response was UCNT (P less than .03). However, node density remained the significant prognostic factor after adjustment for histopathologic type. Follow-up ranged from 16 to 44 months, with a median of 29 months. Patients with grade 1 nodes had a median survival time of 32 months versus 13 months for those with grade 2 nodes (P less than .01). A prospective study should validate the prognostic value of CT node density and its possible use in determining optimal multimodal therapy for advanced head and neck cancers.
Large cystic optic glioma. A 5 1/2-year-old boy developed a huge cyst in his chiasmal glioma 4 years after radiation therapy. The cyst produced obtundation but was successfully treated.