123rc/medical_text huggingface dataset:
Newer antihypertensive agents. Three recent additions to the list of antihypertensive agents have been approved for use as monotherapy or in combination with other drugs. Betaxolol hydrochloride (Kerlone) maintains its effect for 24 hours, making it a true once-a-day beta blocker. Penbutolol sulfate (Levatol) is as effective as other beta blockers and diuretics. Doxazosin mesylate (Cardura), a selective alpha 1 blocker, also allows once-a-day dosing and has produced favorable changes in lipid profiles. Two new drug delivery systems, one for verapamil hydrochloride (Verelan) and one for extended-release nifedipine (Procardia XL), allow less frequent dosing and may offer other advantages, such as greater compliance and a more tolerable side-effect profile.
Patients' expectations of patient-controlled analgesia. Patient-controlled analgesia is an increasingly popular method of postoperative pain relief. However, patients often worry about new therapies. Eighty ASA 1 and 2 patients aged 18-65 years were asked to list the advantages and disadvantages of using patient-controlled analgesia. The most important advantage as perceived by patients was the reduced time spent by nurses in giving medication, but there was concern that direct personal contact would also be lessened. Preservation of self control, autonomy, rapid onset of analgesia, ability to titrate analgesia and lack of injections were seen as an advantage. Addiction and machine faults were seen as minimal problems. Preservation of patient-nurse contact is of great importance to ensure success of postoperative analgesia.
Experimental intracerebral hemorrhage: early removal of a spontaneous mass lesion improves late outcome. The purpose of the present study was to determine whether early removal of an experimental intracerebral mass altered cerebral blood flow, brain water content, neuropathological findings, or neurological function 24 hours later. In three experimental series, a 50-microliter balloon was inflated within the right caudate nucleus in rats. At 24 hours after inflation, we studied cerebral blood flow by quantitative autoradiography, brain specific gravity, and qualitative histopathology by light microscopy. The animals were also assessed using a simple neurological deficit scale. In each series, half of the animals had the balloon inflated for 10 minutes (Group 1), and half had the balloon inflated permanently (Group 2). After transient inflation, there were surprisingly small differences in the blood flow between the two cerebral hemispheres at 24 hours. By contrast, in animals with permanent inflation, several indices of blood flow were significantly worse in the hemisphere ipsilateral to the balloon: the mean and median blood flow levels in the caudate nucleus; the mean blood flow in the cerebral cortex; and the area of cortex with ischemic levels of blood flow. The specific gravity was reduced in areas surrounding the site of balloon insertion after either transient or permanent inflation, and there was evidence of ischemic cell damage in all animals studied. These changes were more severe after permanent inflation, but the differences were not significant. Neurological outcome was significantly better after transient as compared with permanent inflation. The present findings contradict previous results and suggest that early removal of an intracerebral mass may have subsequent benefits.
The effect of thromboxane synthetase inhibition on cardiopulmonary function during endotoxemia in sheep. The early pulmonary hypertension seen with endotoxin (lipopolysaccharide) has been reported as resulting from the release of thromboxane A2. We studied the cardiopulmonary response to endotoxin in sheep with and without treatment with a thromboxane synthetase inhibitor, OKY-046. The animals were implanted with instruments for crystallographic dimension analysis of the left ventricle and measurement of left ventricular, aortic, left atrial, and pulmonary arterial pressures and cardiac index. Thirteen sheep received 1.0 micrograms/kg of Escherichia coli endotoxin with (n = 6) and without (n = 7) OKY-046 (10 mg/kg bolus, then 10 micrograms/kg/min). OKY-046 prevented the increase in pulmonary arterial pressure and decrease in cardiac index usually seen during the early phase of endotoxemia. Between 8 and 12 hours after the administration of endotoxin, cardiac index increased from 6.4 +/- 0.8 to 8.4 +/- 0.8 L/min/m2. Concomitantly, the end-systolic pressure/diameter relationship (a sensitive myocardial contractility index) significantly decreased from 14.7 +/- 0.6 to 7.7 +/- 0.7 mm Hg/mm. Another index of the left ventricular contractility, the maximum rate of pressure rise was also reduced. OKY-046 prevented decreases in end-systolic pressure/diameter relationship and maximum rate of pressure rise.
Genetics and psychiatry: an unheralded window on the environment. Two recent reviews in the American Journal of Psychiatry and the British Journal of Psychiatry reported on progress in understanding the genetics of psychiatric disorder. Both reviews focused on this progress as a prelude to psychiatric diagnostics and therapeutics based on molecular biology. Neither review recognized that the latest data in behavioral genetics support environmental causes for abnormal development and psychopathology as much as they support genetic causes. Moreover, these genetic data point clearly to a type of environmental cause with central importance: the environment that is specific or unique to each sibling in a family.
Orofacial metastasis of pulmonary giant cell carcinoma. A patient was admitted to the hospital with multiple skin nodules of recent origin and signs and symptoms suggestive of acute pulmonary infection. Because one of the skin masses was located overlying the left mandibular body region, the patient was referred to the hospital dentistry clinic for evaluation. Historical, clinical, and radiographic assessments were consistent with reactive lymphadenopathy, and an intraoral excisional biopsy was performed. The biopsy results were indicative of giant cell carcinoma, which was confirmed by biopsy results from a similar skin lesion on the shoulder and by malignant cells recovered in the sputum and pleural fluids. Although this carcinoma has been shown to rarely metastasize to the skin and lymphatics of the neck, this is the first case report of metastasis to facial lymphatics.
MY7 monoclonal antibody for diagnosis of cutaneous T-cell lymphoma. Infiltrate in cutaneous T-cell lymphomas (CTCLs) is composed mainly of CD4 helper cells with a phenotype very similar to that of benign cutaneous lymphoid infiltrate. MY7 (CD13) is a monoclonal antibody that is normally expressed on peripheral granulocytes and monocytes but also cross-reacts with an antigen expressed on epidermal basal cells. We studied MY7 expression on basal cells of the epidermis and CD4 cell infiltrate in 34 CTCLs, 11 pseudolymphomas, and 29 other benign cutaneous lesions. An indirect immunofluorescence technique with double labeling and an immunoperoxidase technique were used. We found that in benign inflammatory infiltrate, less than 10% of CD4 cells expressed MY7 antigen associated with normal MY7 monoclonal antibody labeling of basal cells, whereas in CTCLs more than 50% of CD4 tumoral cells in dermis expressed MY7 antigens; however, basal cells were MY7 negative. Thus, it is demonstrated that MY7 monoclonal antibody with its double modulation on epidermis (basal cells) and dermis (CD4 cells) has diagnostic value for differentiating CTCLs with CD4+ MY7+ tumor cells in dermis and MY7-negative basal cells from benign inflammatory lesions with CD4+ MY7- cells in dermis and MY7-positive basal cells. This modulation of MY7 labeling could be related to the secretion of epidermal cytokines.
Intra-abdominal "angiosarcomatosis" report of two cases after pelvic irradiation. Angiosarcomas account for only 1% to 2% of all soft tissue sarcomas with the most common site of origin being skin and subcutaneous tissue particularly on the face and scalp of elderly patients. These neoplasms rarely arise in the small or large bowel with presentation as diffuse abdominal "angiosarcomatosis." Two patients are reported who were treated with adjuvant pelvic irradiation for gynecologic malignancies (squamous cell carcinoma of the cervix and adenocarcinoma of the endometrium) in whom diffuse abdominal angiosarcoma of intestinal origin developed 7 and 18 years later. Both patients were treated with standard megavoltage irradiation. The clinical course was rapid in both cases with death due to intra-abdominal hemorrhage and bowel obstruction. The pertinent literature relating to the association between radiation therapy and subsequent development of angiosarcomas of soft tissues and other sites is briefly reviewed.
Radiation necrosis of the optic chiasm, optic tract, hypothalamus, and upper pons after radiotherapy for pituitary adenoma, detected by gadolinium-enhanced, T1-weighted magnetic resonance imaging: case report. A 26-year-old woman was treated for a prolactin secreting pituitary adenoma by surgery and radiotherapy (5860 rads). Fourteen months later, she developed right hemiparesis and dysarthria. A T1-weighted magnetic resonance imaging scan using gadolinium contrast showed a small, enhanced lesion in the upper pons. Seven months later, she had a sudden onset of loss of vision, and radiation optic neuropathy was diagnosed. A T1-weighted magnetic resonance imaging scan showed widespread gadolinium-enhanced lesions in the optic chiasm, optic tract, and hypothalamus. Magnetic resonance imaging is indispensable for the early diagnosis of radiation necrosis, which is not visualized by radiography or computed tomography.
Cholesterol cysts of the temporal bone: diagnosis and treatment. Cholesterol cyst (or granuloma) of the temporal bone, a recognized clinical entity distinct from cholesteatoma, is more common than previously thought. Apparently it is caused by obstruction of previously pneumatized temporal bone air cells. Surgical cure is achieved by drainage and reestablishment of normal pneumatization. This paper reviews 14 cholesterol cysts of the temporal bone, emphasizing the importance of preoperative imaging and surgical approach. Use of magnetic resonance imaging differentiates cholesterol cysts from cholesteatoma or other neoplasms. Computed tomography delineates the location of the lesion and defines temporal bone anatomy essential to surgical approach. The two studies together allow the surgeon to properly plan drainage, as in the case of a cholesterol cyst, versus excision or exteriorization, as in the case of cholesteatoma. The infralabyrinthine approach to a petrous apex cholesterol cyst is the procedure of choice when hearing preservation is desired.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.