Melricflash/CW_MedAbstractsAlt huggingface dataset:
Persistence of arrhythmia exercise response in healthy young men. This study assesses the persistence of arrhythmia at rest or during exercise tests, or both, after a mean follow-up period of 6.7 years in 76 young men (mean age 21.5 years) without evidence of organic heart disease. The exercise test was performed using a near-maximal protocol based on progressively increasing intermittent work loads, each of 5 minutes' duration. The initial work load was 50 W. The electrocardiogram was continuously registered throughout all stages of the examination. Arrhythmia was defined as the occurrence of greater than or equal to 1 supraventricular or 1 ventricular premature beat at any stage of the examination. At the follow-up examination, the rate of persistence of arrhythmia did not differ significantly among the subgroups, irrespective of follow-up interval, type of arrhythmia, or arrhythmia patterns of response to exercise. Two-dimensional echocardiography did not show any structural abnormalities and Doppler examination did not demonstrate significant abnormal flow patterns. Our data show that almost all patients continued to present arrhythmia after the follow-up period, without any evidence of development of organic heart disease. Moreover, the arrhythmia pattern of response to exercise remained constant throughout the years. At this time, arrhythmia without underlying heart disease seems to be of a benign natural course in these young men. 

Category: general pathological conditions
Biology of basal cell carcinoma (Part I). Basal cell carcinoma is the most common malignancy in humans. Although rarely metastatic, it is capable of significant local destruction and disfigurement. This two-part article reviews the current understanding of basal cell carcinoma biology. Part I examines significant clinical, histologic, and ultrastructural features that relate to invasive potential. Genetic characteristics, including tumor growth rate, chromosomal abnormalities, and oncogene presence, are discussed, and expression of important cell and matrix proteins, including keratin, fibronectin, and HLA antigens, are reviewed. Further topics to be explored in Part II include host immunologic responses, theories of pathogenesis, and valuable second-line therapeutic regimens for treatment of multiple cancers. 

Category: neoplasms
Two-dimensional echocardiographic features of double outlet left ventricle. In a cyanotic newborn infant, the diagnosis of double outlet left ventricle was made from the two-dimensional echocardiographic examination. The diagnosis was later confirmed at cardiac catheterization and surgery. The parasternal and subcostal views were especially useful for identification of the origin of both great arteries from the morphologic left ventricle. A review of the medical literature since 1967 revealed 77 cases of double outlet left ventricle, most of which were diagnosed only at surgery or postmortem examination. The anatomic features demonstrated with two-dimensional echocardiography in this case are representative of the findings cited most often in the cases reported in the medical literature. 

Category: cardiovascular diseases
The role of alpha adrenoceptor subtypes in sympathetic control of the acral-cutaneous microcirculation. In pithed and anesthetized rats, laser-Doppler flowmetry was used to evaluate the role of alpha-1 and alpha-2 adrenoceptors in mediating sympathetic responses in acral regions of the cutaneous circulation. The intravenous administration of the selective alpha-1 agonist, phenylephrine, was a more potent vasopressor agent than BH-T 933 (a selective alpha-2 adrenoceptor agonist) in pithed rats. However, BH-T 933 was more potent and more efficacious than phenylephrine in reducing cutaneous microvascular perfusion (CP). BH-T 933 also caused a greater increase in cutaneous microvascular resistance. Neural and humoral sympathetic effects on CP were characterized with selective alpha-1 and alpha-2 adrenoceptor antagonists (prazosin and rauwolscine, respectively). It was found that frequency-related reductions in CP elicited by sciatic nerve stimulation were antagonized by prazosin, but not by rauwolscine. In fact, rauwolscine enhanced neurally evoked reductions in CP at the highest stimulation frequencies. However, both prazosin and rauwolscine antagonized reductions in CP elicited by electrical stimulation of the thoracolumbar outflow (sympathoadrenal activation). Ganglionic stimulation (intravenous 1,1-dimethyl-4-phenylpiperazinium) also caused a profound, transient reduction in CP that was abolished by rauwolscine, but was not significantly altered by prazosin. In contrast, 1,1-dimethyl-4-phenylpiperazinium-induced increases in mean arterial pressure were reduced by prazosin, but not by rauwolscine. In ketamine-anesthetized rats, rauwolscine caused a dose-related increase in CP without altering mean arterial pressure, whereas prazosin lowered mean arterial pressure but did not alter CP. We conclude that acral regions of the cutaneous vasculature are more sensitive to alpha-2 vis-a-vis alpha-1 adrenoceptor-mediated vasoconstriction. 

Category: cardiovascular diseases
Genetics of common diseases of adulthood. Implications for prenatal counseling and diagnosis. Genetic factors play an important role in the development of many common diseases of adulthood that result in early morbidity and mortality. Prevention of these disorders and their sequelae is best established through early detection and early intervention. Although it may be feasible to screen the entire population for some disorders (e.g., hypertension), this approach would be expensive and impractical for others (e.g., colon cancer). The family history provides an inexpensive and convenient method of identifying families at risk for premature diseases of adulthood. Family screening for a disorder should be recommended if there is increased risk for the disorder among family members, if screening methods are available to detect the condition at an early age or preclinical stage, and if early intervention will alter the course of the disease. For many disorders screening and intervention can prevent the occurrence of clinical disease. The prenatal counseling session affords an ideal setting for identifying families at risk for diseases of adulthood with major genetic components. By reviewing the family history, key family members can be identified and investigated, in order to establish a specific genetic diagnosis. At-risk relatives can then be counseled and screened for the disorder preclinically and premorbidly. The screening and intervention available for a disease depends on the nature of the disorder, our understanding of its physiology and etiology, and our current technology. The disorders discussed earlier are typical of conditions of adulthood that are influenced strongly by genetic factors, especially when they appear in younger adults. Atherosclerosis, colon cancer, and diabetes are complex phenotypes. Each can be caused by single-gene defects, but commonly the genetics are more complex. Empiric data help to establish the risk to an individual in the latter cases. In all three examples, early detection should lead to treatment, which can prevent more serious sequelae: by treating the dyslipidemia, coronary artery disease can be prevented; by removing the benign polyp, malignant cancer can be avoided; and when impaired glucose tolerance is detected, diet and exercise can prevent or delay frank diabetes and its complications. The complete evaluation of individuals at risk for disorders such as those in Table 1 and their families can be a complicated task. Referral to a center experienced in the genetics of common diseases often may be necessary.(ABSTRACT TRUNCATED AT 400 WORDS). 

Category: neoplasms
Fine structure of active and healed duodenal ulcer. In order to characterize the fine structure of active and healed duodenal ulcers, we examined tissue specimens of patients with active duodenal ulcer disease (n = 30) before and after treatment with either antacids (n = 16) or H2-receptor antagonists (n = 14), by light microscopy and various electron microscopic techniques, e.g., scanning and transmission electron microscopy. The characteristic histological feature of both the active and healed duodenal ulcer was the appearance of periodic acid-Schiff (PAS)-positive epithelial cells at the edge of the ulcers. Electron microscopy revealed that these cells were similar to a special type of mucus-secreting cell in the antrum (surface mucous cell). Their mucus granules contained mainly neutral glycoproteins. Helicobacter pylori were found attached to these cells in tissue specimens from 12 of 30 patients (40%). The mucous structure destroyed during the ulcerative phase regained its normal net-like structure after treatment. The ultrastructural healing process of duodenal ulcer was characterized by the presence of gastric metaplasia, by stunted microvilli of the duodenal epithelium (p less than 0.001 vs. control group), and an increased number of lysosome-like bodies (p less than 0.001 vs. control group) of the epithelial cells. These results were independent of the type of treatment, and showed that the repair mechanisms were incomplete after a 4-wk period of treatment. 

Category: general pathological conditions
Bone sarcomas as second malignant neoplasms following childhood cancer. This study explores the relationship between histologic variants of bone sarcomas and previous therapy in patients in whom an unrelated malignant neoplasm had been diagnosed during childhood. Sarcomas of bone were the most common second malignant neoplasm (SMN) reported to the Late Effects Study Group, a 13-institution consortium consisting of pediatric oncology centers from western Europe, Canada, and the United States. The authors attempted to relate the histologic subtypes of the 91 bone tumors to clinical factors such as previous therapy and genetic predisposition because morphologic variants have been shown to have biologic significance in other tumors and may have etiologic import. The literature concerning the subtypes of bone tumors, clinical and experimental, is also reviewed. The authors also investigated the effect of several factors on the time interval from the first diagnosis to the SMN (i.e., the bone sarcoma). Anthracyclines significantly shortened the interval by about 3 years. The primary diagnosis also significantly affected the interval, with leukemia/lymphomas having the shortest interval and retinoblastoma the longest. The authors could not demonstrate any significant relationship between morphologic characteristics of the osteosarcoma and predisposing conditions. However, lesions diagnosed as chondrosarcoma and malignant fibrous histiocytoma occurred almost exclusively in patients who had received radiation therapy to the site in which the SMN developed. 

Category: neoplasms
Factors predictive of results of direct ablative operations for drug-refractory ventricular tachycardia. Analysis of 80 patients. During a 9-year period 80 patients with drug-resistant sustained ventricular tachycardia underwent direct surgical ablation of arrhythmogenic myocardium. Sixty-nine were male (86%) and 11 female (14%), with 1.9 +/- 1.1 (standard deviation) ventricular tachycardia morphologies per patient. The mean number of drugs failed was 3.7 +/- 1.6 per patient. The preoperative left ventricular ejection fraction was 36.4% +/- 14.4%. Complete preoperative endocardial mapping data (greater than 4 endocardial sites in each ventricular tachycardia) were available for 60 of the 80 patients (75%) and intraoperative endocardial data in the clinical ventricular tachycardia was obtained in 37 (46.3%) of the patients. In 17 patients mapped intraoperatively by computer-assisted techniques, complete epicardial and endocardial data in the clinical ventricular tachycardia were obtained in 14 patients (82.4%). Overall, 73 of 80 (91.3%) had some mapping data available. Hospital mortality occurred in 10 patients (12.5%) at a mean interval of 13.5 days, range 0 to 62 days. Postoperatively the clinical ventricular tachycardia has not recurred in 65 of 70 surviving patients (92.9%). Nonclinical ventricular tachycardia occurred in another four patients. All nine patients with postoperative ventricular tachycardia responded to drugs. The major factors predictive of hospital mortality were prolonged cardiopulmonary bypass (greater than 150 minutes), preoperative ejection fraction less than 31%, and incomplete preoperative mapping. Hospital mortality in patients with an ejection fraction below 31% was significantly associated with a history of amiodarone usage. At 3 years of follow-up, freedom from sudden cardiac death was 95.7%, and 86.7% of patients were free of ventricular tachycardia on no antiarrhythmic drugs. These results suggest that direct ventricular tachycardia operations are an effective form of therapy for patients with sustained monomorphic ventricular tachycardia. 

Category: cardiovascular diseases
Excision repair of pyrimidine dimers induced by simulated solar radiation in the skin of patients with basal cell carcinoma. One prominent lesion induced in DNA by ultraviolet (UV) radiation is the cyclobutyl pyrimidine dimer formed between adjacent pyrimidines on the same DNA strand. We investigated whether people who have developed basal cell carcinoma on sun-exposed skin have an altered ability to repair UV-induced pyrimidine dimers in DNA. Twenty-two patients with at least one basal cell carcinoma, aged 31-84 years, and 19 healthy volunteers, aged 25-61 years, took part in the study. Both groups were given one minimal erythema dose (MED) of simulated solar radiation on the lower back. DNA was extracted from the irradiated skin 0 to 6 h later, and the number of UV-induced pyrimidine dimers was determined using a dimer-specific endonuclease. At time 0, the average number of dimers per unit of DNA was similar in the two groups. After 6 h, an average of 22 +/- 4% of the dimers were removed in the group with basal cell carcinoma compared to 33 +/- 4% in the cancer-free group. In the basal cell carcinoma group, only 23% of the patients repaired more than 30% of the dimers after 6 h, compared with 53% of the cancer-free subjects (p less than 0.05). We conclude that patients who develop basal cell carcinoma on sun-exposed skin may have a decreased ability to repair pyrimidine dimers induced in skin exposed to simulated solar radiation. 

Category: neoplasms
Hypoplastic transverse arch and coarctation in neonates. Surgical reconstruction of the aortic arch: a study of sixty-six patients. From Jan. 1, 1983, to Jan. 1, 1988, 66 consecutive neonates with coarctation and severe hypoplasia of the transverse arch underwent coarctation repair by resection of the coarctation and reconstruction of the aortic arch. Mean age at operation was 14 +/- 8 days, ranging from 2 to 30 days; 63% of the newborn infants were less than 2 weeks of age. The coarctation was isolated in 23%, associated with a ventricular septal defect in 39%, and associated with complex anomalies in 38%, including 16 cases of transposition of the great arteries or doublet-outlet right ventricle plus ventricular septal defect, two cases of simple transposition, two of corrected transposition plus ventricular septal defect, and five cases of "hypoplastic" left ventricle. The surgical technique comprises a wide resection of the coarctation extended to the contiguous ductal tissue followed by the reconstruction of the aortic arch in bringing the descending aorta into the concavity of the aortic arch. This technique is able to relieve the obstruction of the aortic arch provided that (1) the descending aorta is widely dissected to allow mobilization and (2) the incision of the transverse arch is extended proximal to the ostium of the left carotid artery. The operation was performed through a left thoracotomy in 62 patients and through a sternotomy in four additional neonates with transposition and ventricular septal defect who underwent a one-stage repair with aortic reconstruction, closure of the defect, and arterial switch. The overall early mortality rate (less than 30 days) was 14% (9/66; 95% confidence limits = 5% to 22%), including four deaths occurring within the first month, at a concomitant or subsequent repair of the associated anomaly. There were six late deaths, all related to the associated lesions. The overall mortality rate was 23% (15/66; 95% confidence limits = 13% to 33%). The mean follow-up was 21 +/- 10 months, ranging from 6 to 66 months. Actuarial survival rates at 5 years are 72% +/- 10% for the overall group; 87% +/- 17% for simple coarctation; 88% +/- 12% for coarctation and ventricular septal defect; and 52% +/- 18% for complex coarctation. The rate of recurrent coarctation was 12.5% (95% confidence limits = 2% to 23%), leading to five reoperations with no deaths. Freedom from reoperation was 89.5% +/- 9% at 5 years. This technique of coarctation repair offers several advantages: low operative mortality, complete relief of the left ventricular obstruction, wide resection of the ductus tissue, absence of prosthetic material, and preservation of the left subclavian artery. 

Category: general pathological conditions
Chronic dehydration stone disease. A study was made of 819 patients attending a metabolic stone clinic. A firm diagnosis was made in 708 (86%) and in 132 of these (19%) the diagnosis was thought to be chronic dehydration. The records were available for study for 87 males and 11 females in the chronic dehydration group. The mean age at presentation was 43 years. The causes of chronic dehydration were hot climate (62%), with hot occupation and low water intake almost equal in second place. In patients with a single cause of chronic dehydration, 57% also had a dietary risk factor for urolithiasis and this was most commonly high oxalate intake. Following dietary advice, the mean urinary volume increased from 1720 to 2475 ml/24 h. This was accompanied by a rise in mean urinary calcium from 6.02 to 6.96 mmol/24 h, presumably due to the calcium in the additional water drunk. Urinary oxalate did not change significantly. The mean follow-up time was 4.85 years and the stone recurrence rate was low. It was concluded that chronic dehydration is a common cause of urolithiasis; this can be treated satisfactorily by increasing water intake plus dietary advice in certain cases. 

Category: general pathological conditions
A newly established human osteosarcoma cell line with osteoblastic properties. A human osteosarcoma cell line, HuO9, was established from a tumor that was heterotransplanted into athymic nude mice. Antiserum against nude mouse spleen cells was added to the early passage cultures to eliminate the host fibroblastic cells. The cell line retained a high activity of liver/bone/kidney-type alkaline phosphatase (ALP) and secreted osteocalcin, i.e., bone gamma-carboxyglutamic acid-containing protein (BGP), into the medium. The addition of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) increased the ALP activity as well as the level of BGP secreted into the medium. The ALP of 1,25(OH)2D3-treated cells has the same inhibition characteristics to heat and amino acids as that of untreated cells. Synthetic human parathyroid hormone stimulated the production of intracellular adenosine 3',5'-cyclic monophosphate (cAMP) approximately 100-fold within five minutes. However, the stimulation was not observed with a synthetic human thyrocalcitonin. When HuO9 cells were transplanted into the back of a nude mouse, a tumor with an abundant osteoid formation and mineralization was produced. The results indicate that the HuO9 cell line expresses well-differentiated osteoblastic phenotypes. HuO9 is the first established human cell line to produce BGP, and it provides a useful model for the studies of osteoblasts and the regulatory mechanisms of BGP production. 

Category: neoplasms
Multiple granular cell tumors associated with giant speckled lentiginous nevus and nevus flammeus in a child. We describe an 11-year-old girl in whom multiple cutaneous granular cell tumors were associated with a giant speckled lentiginous nevus and an extensive nevus flammeus. An association between granular cell tumors and pigmented skin lesions has been reported twice previously and supports a neural origin for these tumors. An abnormality of neural crest development is proposed to explain the coexistence of three uncommon and unusually extensive cutaneous disorders in this patient. This case may represent a further variant of phakomatosis pigmentovascularis. 

Category: neoplasms
Prospective study on prevalence of esophageal chest pain in patients referred on an elective basis to a cardiac unit for suspected myocardial ischemia. The prevalence of esophageal chest pain was studied prospectively in patients referred on an elective basis to a cardiac unit for suspected myocardial ischemia. A group of 248 consecutive patients without previously documented heart disease was admitted for elective diagnostic coronary angiography. The clinical history classified 185 patients as having anginal pain and the coronary angiogram was normal in 48 of them. In 37 of these 48 patients full esophageal testing was performed including 24-hr intraesophageal pH and pressure recordings with indication of chest pain episodes as well as a number of esophageal provocation tests, ie, acid perfusion, edrophonium stimulation, balloon distension, and ergonovine stimulation, all performed under continuous esophageal manometric and electrocardiographic monitoring. In 19 of these 37 patients, the familiar chest pain could be reproduced by esophageal provocative testing without ischemic ST-T segment alterations; six of these 19 patients had also a positive 24-hr pH and pressure recording. These data strongly suggest an esophageal origin of chest pain in half the patients with typical angina and a normal coronary angiogram. 

Category: digestive system diseases
Endoscopic coagulation of the choroid plexus using the Nd:YAG laser: initial experience and proposal for management. Although most patients with hydrocephalus are treated effectively with ventriculoperitoneal shunts, a small group fails to respond to diversion procedures. In some patients within this group, hydrocephalus may be caused in part by the overproduction of the cerebrospinal fluid (CSF). In other patients, previous shunt infections may limit the ability of the peritoneum to absorb fluid, and patient response to a ventriculoperitoneal shunt may be improved by reducing CSF production. We discuss a case of a 29-month-old hydrocephalic infant with a ventriculoperitoneal shunt who had ascites. Computed tomography showed bilateral symmetrical enlargement of the choroid plexus. Repeated cultures of the CSF and shunt tubing were sterile, and the daily production of the CSF exceeded 1000 ml. Therapy with acetazolamide decreased the CSF output temporarily, but it was discontinued after serious electrolyte abnormalities occurred. The endoscopic coagulation of the choroid plexus with a neodymium:YAG laser transmitted through a flexible quartz fiber decreased CSF production effectively. This procedure may be useful in a variety of clinical conditions associated with hydrocephalus or with other intraventricular lesions. 

Category: general pathological conditions
Spinal cord stimulation: a contemporary series Forty-three patients with chronic pain disorders of different causes were selected for spinal cord stimulation. All underwent implantation of a ribbon electrode through a small laminotomy, under general anesthesia. Thirteen patients (30%) failed to obtain significant pain relief during a period of trial stimulation, and their electrodes were removed. The remainder underwent a definitive implant and were followed for a mean of 13 months (range, 3-33 months). Nineteen of them (63%) continued to experience pain relief. A detailed analysis of this series, as well as a literature review, is presented. 

Category: nervous system diseases