123rc/medical_text huggingface dataset:
Results of conservative surgery and radiation therapy for breast cancer. For stage I or II breast cancer, conservative surgery and radiation therapy are as effective as modified radical or radical mastectomy. In most cases, cosmetic considerations and the availability of therapy are the primary concerns. The extent of a surgical resection less than a mastectomy has not been a subject of a randomized trial and is controversial. It appears that removal of a quadrant of the breast for small lesions is safe but excessive. Using histologic findings in the biopsy as a guide, it may be possible to limit the breast resection to gross tumor removal for most patients while using wider resections for patients with an extensive intraductal component or for invasive lobular carcinoma. It also appears that excluding patients from breast conservation on the basis of positive margins on the first attempt at tumor excision may be unnecessarily restrictive. Although patients with an extensive intraductal component or invasive lobular carcinoma should have negative margins, it appears that a patient with predominantly invasive ductal carcinoma can be treated without re-excision if all gross tumor has been resected and there is no reason to suspect extensive microscopic disease. Patients with indeterminate margins should have a re-excision. Axillary dissection provides prognostic information and prevents progression of the disease within the axilla. Axillary dissections limited to level I will accurately identify a substantial number of patients who have pathologically positive but clinically negative nodes. When combined with radiation therapy to the axilla, a level I dissection results in a limited number of patients with progressive axillary disease. Patients with pathologically positive axillas and patients at particularly high risk for systemic disease because of the extent of axillary node involvement can be identified by dissections of levels I and II. Radiation therapy can be avoided safely in patients who have pathologically negative axillas by level I and II dissection. There appears to be no advantage to routine dissection of level III lymph nodes. Lymphedema of the arm and breast increases with more extensive dissections and with radiation therapy.
Comparison of two doses of endotracheal epinephrine in a cardiac arrest model. STUDY OBJECTIVE: The objective of this study was to measure plasma catecholamine levels and the cardiovascular response before and after endotracheal administration of epinephrine in a swine cardiac arrest model. DESIGN: Prospective, controlled laboratory investigation. TYPE OF PARTICIPANTS: Twenty-one swine weighing 10 to 12 kg, anesthetized with ketamine and alpha-chloralose and ventilated with room air. INTERVENTIONS: Ventricular fibrillation was induced with 90 V of 60 Hz current delivered to the right ventricle by transvenous pacemaker. Blood samples for epinephrine were drawn before arrest and every two minutes thereafter. At five minutes, external mechanical cardiac compressions were initiated. Nine animals received no further therapy and served as controls. Two groups of six animals received either 0.01 mg/kg or 0.1 mg/kg of epinephrine through the endotracheal tube at ten and 20 minutes. Blood samples were assayed for epinephrine. MEASUREMENTS: Arterial blood pressure, lead II ECG, and plasma epinephrine. MAIN RESULTS: Swine receiving epinephrine 0.01 mg/kg had an increase in epinephrine levels after drug administration, but these were not significantly different from control levels. The 0.1-mg/kg dose group had a significant increase in plasma epinephrine levels compared with controls and the 0.01-mg/kg dose group after receiving epinephrine at ten and 20 minutes. These increases were from 14 +/- 3 to 215 +/- 40 ng/mL (+/- SEM) at 12 minutes after arrest and from 151 +/- 56 to 402 +/- 80 ng/mL at 22 minutes after arrest. CONCLUSION: These data suggest that standard dosing of epinephrine through the endotracheal tube during arrest does not produce significant increases in plasma catecholamines or blood pressure. Epinephrine 0.1 mg/kg produces a significant increase in plasma epinephrine levels, but it is not sufficient to produce a significant change in blood pressure.
SPECT imaging of pediatric brain tumor with hexakis (methoxyisobutylisonitrile) technetium (I). Technetium-99m-Hexamibi [Hexakis (methoxyisobutylisonitrile) technetium (i)] was developed as a myocardial perfusion agent with biologic properties similar to those of thallium-201 (201TI). As 201TI has recently been observed to be of value for the diagnosis of brain tumors when used in conjunction with single-photon emission computed tomography (SPECT) imaging technology, the possibility that the biologic similarity of the two radiopharmaceuticals extended to their affinity for tumors was tested. A 5-yr-old female patient with a brain stem astrocytoma showed marked focal uptake of 99mTc-Hexamibi at the site of tumor recurrence as defined by biopsy and prior 201TI/SPECT study. Tumor-to-normal cortex radioactivity ratios for the 99mTc-Hexamibi/SPECT study were 132:1 and the spatial resolution of the 99mTc-Hexamibi images was high. This observation suggests that 99mTc-Hexamibi merits further study as a potential agent for SPECT imaging of human brain tumors.
Time course of hemodynamic responses to sodium in elderly hypertensive patients. Thirty-one patients with essential hypertension (81.6 +/- 6.9 years old) were studied during two different regimens of sodium intake: 120 meq/day for 8 weeks and 344 meq/day for 2 weeks. Systemic hemodynamic data were measured with Doppler echocardiography from which the mitral flow velocity integral, cardiac index, and total peripheral resistance were calculated. The salt-sensitive patients in whom the increase in total peripheral resistance was greater than the increase in cardiac index with salt loading were termed SST. In the salt-sensitive patients termed SSC, the increase in cardiac index was greater than the increase in total peripheral resistance with increased sodium intake. All SST patients on day 7 of the high sodium diet remained in the SST group on day 14. Nine of 13 patients in the SSC group on day 7 remained in the SSC group on day 14, and the remaining four patients in the SSC group on day 7 fell into the SST group on day 14. Four of eight non-salt-sensitive (NSS) patients on day 7 of the high salt regimen remained in the NSS group on day 14, whereas the remaining four patients in the NSS group on day 7 fell into the SSC group on day 14. Our data suggest a changing pattern with sodium loading of initially high cardiac index followed by a persistently raised total peripheral resistance. The celiac, superior mesenteric, and renal arteries vasoconstricted with sodium repletion in both SST and SSC patients. With salt loading, the terminal aortic vascular bed vasodilated in the SSC patients and vasoconstricted in the SST patients.
Mutation of the prion protein in Libyan Jews with Creutzfeldt-Jakob disease. BACKGROUND. Creutzfeldt-Jakob disease is a transmissible neurodegenerative disorder that occurs more than 100 times more frequently among Libyan Jews than in the worldwide population. We examined 11 patients with the disease--10 Libyan Jews from Israel and 1 Libyan Jew from Italy--to determine whether abnormalities of the prion protein could be detected in them. Abnormal forms of this host-encoded protein are the predominant if not sole components of the transmissible agent that causes the disease. METHODS. The prion-protein open-reading frame in peripheral-leukocyte DNA from the Italian patient was amplified with the polymerase chain reaction and sequenced. Allele-specific oligonucleotide hybridization was used to assess a prion-protein codon 200 lysine mutation in the 10 Israeli patients and 37 control subjects. RESULTS. The prion-protein sequence in DNA from the Italian patient revealed a single nucleotide change (G----A) at the first position of codon 200 that resulted in a substitution of lysine for glutamate. This substitution was detected in all 10 Israeli patients, 8 of whom had a positive family history of Creutzfeldt-Jakob disease. One patient was homozygous for the lysine mutation, and her clinical course did not differ from that of the patients heterozygous for the mutation. The lysine mutation was not found in one Moroccan Jew from Israel with Creutzfeldt-Jakob disease. CONCLUSIONS. The codon 200 lysine mutation of the prion-protein gene is consistently present among Libyan Jews with Creutzfeldt-Jakob disease, strongly supporting a genetic pathogenesis of their illness. The similarity of the clinical courses of the patient homozygous for this mutation and the patients heterozygous for it argues that familial Creutzfeldt-Jakob disease is a true dominant disorder.
Tumor cell heterogeneity and subpopulations with metastatic ability in differentiated adenocarcinoma of the lung. Histologic and cytofluorometric DNA analyses. To investigate tumor cell heterogeneity and subpopulations with metastatic ability in differentiated adenocarcinoma of the lung, the primary and metastatic lesions in 20 cases of differentiated adenocarcinoma were examined by histologic and cytofluorometric DNA analyses. The primary tumor was divided histologically into three compartments: tumor area of type 1, papillary adenocarcinoma with thin stroma; tumor area of type 2, papillary adenocarcinoma with thickened fibrovascular stroma: tumor area of type 3; solid carcinoma with scant gland formation. The nuclear DNA content (NDC) was higher in type 2 than in type 1 tumor in terms of mean NDC and DNA histogram pattern (p less than 0.01). Metastatic tumors in distant organs often resembled the type 2 of primary tumors histologically and also in their DNA histogram patterns, and their mean NDC values were significantly correlated with each other (p less than 0.01). Metastatic tumors in regional lymph nodes had a significantly lower mean NDC than those in distant organs (p less than 0.01). These results suggest that (1) type 2 tumors originate from type 1 tumors by malignant progression and metastasize hematogenously, and (2) hematogenous metastases are composed of tumor subclones different from those of lymphatic metastases.
The influence of neutralizing heparin after carotid endarterectomy on postoperative stroke and wound hematoma. The influence of neutralizing or not neutralizing heparin after carotid endarterectomy on postoperative stroke and wound hematoma is unknown. During the past 6 years some of the authors frequently gave protamine sulfate to neutralize heparin, whereas others did not unless a patch was used or wound hemostasis was not readily obtained. To determine the influence of protamine sulfate on stroke and wound hematoma the records of 697 patients having a carotid endarterectomy from January 1984 to September 1989 were reviewed. Protamine sulfate was given to 328 patients, and 369 did not receive protamine sulfate. The incidence of stroke in the two groups was 1.8% (n = 6) and 2.7% (n = 10), respectively, and the difference was not significant (p = 0.6019). Excluding three strokes that could not be related to neutralizing or not neutralizing heparin, the difference remained insignificant (1.5% vs 2.2%, p = 0.7290). The incidence of wound hematoma was 1.8% (n = 6) in patients given protamine sulfate and 6.5% (n = 24) in patients not given protamine sulfate, and this difference was significant (p = 0.0044). The difference remained significant when three hematomas not related to protamine sulfate were excluded (1.2% vs 6.2%, p = 0.0013). In patients not given protamine sulfate draining the wound lessened the incidence of wound hematoma (4.4% vs 8.6%), but this difference was not statistically significant (p = 0.1475). In patients given protamine sulfate the dose of protamine sulfate (15 to 45 mg vs 50 to 75 mg) had no statistically significant effect on the incidence of stroke (0.8% vs 2.0%, p = 0.6530) or wound hematoma (1.6% vs 1.0%, p = 1.000).
Leiomyoma of a digital artery. Benign, soft-tissue masses of the hand are common. A vascular leiomyoma is an unusual tumor of smooth-muscle origin. In a 62-year-old man, the tumor arose from within a digital artery. Persistent symptoms prompted an excisional biopsy, requiring resection of a portion of the artery. Adequate collateral circulation preempted the need for a vascular graft. Vascular repair or grafting may be necessary if collateral circulation is not adequate.
Quantitative analysis of antibody localization in human metastatic colon cancer: a phase I study of monoclonal antibody A33. A33 is a mouse immunoglobulin G2a (IgG2a) monoclonal antibody (mAb) that detects a heat-stable, protease- and neuraminidase-resistant epitope. The antigen is homogeneously expressed by virtually all colon cancers and in the colon mucosa but not other epithelial tissues. The biodistribution and imaging characteristics of iodine-131 (131I)-mAbA33 were studied in colorectal carcinoma patients with hepatic metastases. Antibody labeled with 2 to 5 mCi of 131I was administered intravenously (IV) 7 to 8 days before surgery at five dose levels, ranging from 0.2 mg to 50 mg, with three or more patients entered at each dose level. In addition, three patients received 2 mg 131I-mAbTA99 (an isotype-matched control mAb) together with 125I-mAbA33. Evaluation included whole-body imaging with a gamma camera, technetium-99 (99mTc)-human serum albumin blood pool scans, liver/spleen scans, abdominal computed tomographic (CT) scans, hepatic arteriograms, antibody pharmacokinetics, and assessment of antibody distribution in biopsied malignant and normal tissues. Selective mAbA33 localization to tumor tissue was demonstrated in 19 of 20 patients, and external imaging correlated with surgical inspection, pathologic examination, and tissue radioactivity. One week after antibody administration, tumor:liver ratios ranged from 6.9:1 to 100:1 and tumor:serum ratios from 4.1:1 to 25.2:1. 99mTc-albumin blood pool studies showed that liver metastases were hypovascular, emphasizing the selective localization of mAbA33 despite poor tumor-blood flow. Control mAbTA99 studies showed mAbA33 localization was antigen-specific; tumor:liver ratios were 2.3- to 45-fold higher for specific antibody. In metastatic lesions, radioisotope was localized primarily in the viable periphery; however, even the necrotic tumor core concentrated specific antibody. External imaging showed isotope visualization in some patients' large bowel; whether this represents specific antibody uptake or gastric iodine secretion is unclear.
Amiloride blocks the onset of ACTH-induced hypertension in the sheep. This study investigated the ability of two diuretics, amiloride and frusemide, to prevent the development of ACTH induced hypertension in conscious sheep. Infusion of amiloride (20 mg/day) or frusemide (50 mg/day) for three days into normotensive sheep did not have any significant effects on blood pressure. Amiloride blocked ACTH-induced hypertension and the sodium retention and hypokalemia which is usually associated with ACTH administration. Frusemide failed to completely block the hypertension and potassium loss, however it blocked the transient initial urinary sodium retention associated with ACTH-induced hypertension. As frusemide failed to completely block the hypertension it is unlikely that the amiloride effect is due primarily to effects on urinary Na excretion. It is possible that amiloride is exerting its antihypertensive effects by blocking sodium channels.
5-Aminosalicylic acid is a potent inhibitor of interleukin 1 beta production in organ culture of colonic biopsy specimens from patients with inflammatory bowel disease. Interleukin 1 beta in biopsy specimens from inflamed colonic mucosa of patients with active inflammatory bowel disease was studied. Compared with normal colonic mucosal biopsy specimens, a significantly greater amount of interleukin 1 beta was present in rectal mucosa before (median (range) 4.3 (2.0-11.8) v 119.2 (30.1-286.8) pg/mg; p less than 0.01) and produced during organ culture (39.1 (9.4-106.8) v 97.6 (28.2-991.6) pg/mg; p less than 0.01). Values of interleukin 1 beta after culture correlated with concentrations of thromboxane B2. Organ culture of inflamed biopsy specimens in the presence of 5 aminosalicylic acid and dexamethasone reduced the amount of interleukin 1 beta detected. At the doses studied, 5 aminosalicylic acid also reduced the amount of leukotriene B4 detected after culture.
Histocompatibility testing in transplantation. The question of whether or not HLA is important in transplantation can now be answered with a definite yes. The nationwide six-antigen-matching program, in which over 100 US transplantation centers have participated, has shown that a high (88% to 90%) 1-year graft survival rate can be achieved when kidneys are shipped to well-matched recipients. Long-term outcome (measured as half-life) is also markedly improved, from an average of 7 years for cadaveric donor transplants to as much as 19 years in the six-antigen-matched recipients. One of the major factors influencing long-term survival is histocompatibility matching, as shown by the survival differences among HLA-identical siblings (25-year half-life), one-haplotype-mismatched parental donors (12-year half-life), and two-haplotype-mismatched cadaveric donors (7-year half-life). For the past 25 years of kidney transplant experience, cadaveric donor half-life has remained stable at 7 years, despite many improvements in immunosuppression protocols. Histocompatibility matching unquestionably offers the best approach to prevention of chronic rejection.
Bleeding complications associated with cardiopulmonary bypass. Bleeding after CPB has been difficult to characterize and its treatment equally difficult to standardize. The complexity of this problem is related to the hemostatic process, the technical variations in the operative procedures, and the many uncontrolled variables associated with CPB, including the effects of anesthetic or pharmacologic agents, the nature of the priming solution, hemodilution, hypothermia, the type of oxygenator, and the use of transfused blood products. Although there are multiple and generally predictable complex changes in the hemostatic mechanism during CPB, the temporary loss of platelet function is the most common and clinically relevant. This transient platelet dysfunction occurs in all patients undergoing CPB; however, it only causes excessive bleeding in a small percentage of patients. Unfortunately, it has not yet been possible to predict which patients will develop hemorrhagic complications, although prolonged pump times are a contributing risk factor. Over the past decade there has been extensive investigation into the management of bleeding associated with CPB, provoked primarily by the increased awareness of transfusion-transmitted viral diseases and the inappropriately excessive use of homologous blood products. Several approaches to autotransfusion of shed blood and autologus blood donation have been developed to minimize perioperative homologous blood transfusion. Pharmacologic agents such as desmopressin, aprotinin, and topical fibrin glues have also been introduced to improve hemostasis during CPB. The protease inhibitor aprotinin is particularly promising in the reduction of bleeding associated with CPB when given prophylactically. Aprotinin may provide new insights into the mechanism of CPB-induced platelet dysfunction. Desmopressin is indicated only for the treatment of bleeding after CPB. The management of bleeding associated with CPB will undoubtedly.
Retroperitoneal air after routine hemorrhoidectomy. Report of a case. Retroperitoneal air as a complication after routine hemorrhoidectomy has not been reported in the literature. This occurred recently after hemorrhoidectomy in a 34-year-old patient receiving glucocorticoid therapy for rheumatoid arthritis. Adverse steroidal effects of wound healing have been well documented. It is believed that steroid-induced tissue changes contributed to the development of this unique complication.
Late results with Carpentier-Edwards porcine bioprosthesis. From 1977 to 1984, 429 patients underwent aortic valve replacement (AVR), and 339 underwent mitral valve replacement (MVR) with a Carpentier-Edwards bioprosthesis. Early mortality for AVR was 4.6% (isolated AVR, 1.9%) and for MVR was 5.3% (isolated MVR, 4.1%). Follow-up was 99.3% complete at a mean of 5.9 years. Actuarial event-free rates at 10 years for AVR and MVR were, respectively, 1) for structural valve deterioration, 91.4 +/- 3.2% versus 75.1 +/- 4.0% (p less than 0.01); 2) for nonstructural dysfunction, 100% versus 97.8 +/- 1.6% (p = NS); 3) for thromboembolism, 90.6 +/- 2.3% versus 87.3 +/- 2.6% (p = NS); 4) for anticoagulant-related bleeding, 95.3 +/- 1.1% versus 88.6 +/- 2.4% (p = 0.05); 5) for endocarditis, 87.8 +/- 5.7% versus 90.6 +/- 2.4% (p = NS); 6) for reoperation, 91.0 +/- 2.5% versus 74.4 +/- 3.7% (p less than 0.01); 7) for valve-related mortality, 76.1 +/- 6.9% versus 71.4 +/- 5.2% (p = 0.01); 8) for permanent physical impairment, 85.0 +/- 3.0% versus 71.5 +/- 3.6% (p less than 0.01); and 9) for combined operative mortality, valve-related mortality, and reoperation, 68.7 +/- 6.4% versus 51.5 +/- 4.9% (p = 0.01). No structural valve dysfunction was observed in any AVR patient whose valve was inserted after age 70. Age at operation was the only factor that predicted structural valve deterioration (p less than 0.01).
Acute changes in the dynamics of the cerebrospinal fluid system during experimental subarachnoid hemorrhage. Early changes in intracranial pressure (ICP), ICP volume index, and resistance to absorption of cerebrospinal fluid induced by experimental subarachnoid hemorrhage were studied in cats. After SAH, the ICP was slightly elevated, and there was a decrease in the buffering capacity of the intracranial space and a sharp rise in outflow resistance. During infusion of blood into the cisterna magna with a constant infusion rate, an extensive increase in ICP could be demonstrated in contrast to the infusion of saline, which caused only slight elevation of ICP. Furthermore, during blood infusion, the ICP level did not reach a plateau phase of pressure, as was demonstrated during infusion of saline. It is suggested that the marked increase in ICP during blood infusion into the subarachnoid space is caused by intracranial volume loading and the simultaneous increase in cerebrospinal fluid outflow resistance. It is concluded that the reported relationship between increased cerebrospinal fluid outflow resistance and increased ICP supports the hypothesis of a strong increase in ICP during subarachnoid hemorrhage in human subjects.
Evolution of deep venous thrombosis: a prospective evaluation with US. Forty-six patients with a diagnosis of acute deep venous thrombosis (DVT) established by means of duplex ultrasound (US) were prospectively followed up with serial duplex US examinations during a 6-month period to assess the persistence of venous abnormalities. All patients were asymptomatic. Isolated popliteal DVT was found to be more likely to revert to normal at duplex compression US than thrombosis involving both the femoral and popliteal systems (P less than .05). Increased venous diameter was a sign of acute clot (P less than .005). Clot echogenicity did not help to enable distinction of acute DVT and chronic DVT. At compression US, 10 of 21 patients (48%) who initially had occlusive thrombosis had persistent abnormalities that mimicked findings consistent with acute DVT. Chronic venous changes that persisted after 6 months consisted of either lumen recanalization (with resultant intimal thickening) or persistent venous occlusion. Both of these conditions can result in incomplete compression, the major US indication of acute DVT. This appearance should not be confused with that of acute DVT. Follow-up examinations to establish a baseline appearance can be obtained as early as 6 months after an acute episode of DVT.