shukoor65/lab-rag-model huggingface dataset:
Pulmonary embolism update. Lessons for the '90s. Pulmonary embolism continues to be an underdiagnosed, potentially fatal problem. Because clinical diagnosis of pulmonary embolism is notoriously inaccurate, clinical suspicions must always be confirmed with objective studies. Evaluation generally begins with ventilation-perfusion lung scanning. Further evaluation is usually unnecessary if the lung scan is interpreted as normal (diagnosis excluded) or high-probability (diagnosis accepted). However, if the lung scan is indeterminate (referring to all other interpretations), additional diagnostic studies are usually required. Newer trends in the management of pulmonary embolism and deep venous thrombosis include a more aggressive initial regimen of heparin; simultaneous administration of warfarin with heparin, resulting in a shorter duration of heparin therapy; use of the international normalized ratio to monitor warfarin therapy; and use of a less intense warfarin regimen. Adjusted-dose subcutaneous heparin therapy and low-intensity warfarin therapy are newer prophylactic techniques for patients at moderate to high risk for deep venous thrombosis.
Early onset cerebellar ataxia with retained tendon reflexes. Clinical, electrophysiological and MRI observations in comparison with Friedreich's ataxia. Fourteen patients with the clinical diagnosis of early onset cerebellar ataxia with retained tendon reflexes (EOCA) were examined and compared with 11 patients with Friedreich's ataxia (FA). The mean age of onset in EOCA was 15.9 +/- 6.0 yrs (FA: 14.0 +/- 5.7 yrs). Annual progression rate and the percentage of patients who were wheelchair-bound was lower in EOCA as compared with FA, although the difference did not reach statistical significance. The latency until becoming wheelchair-bound, however, was significantly longer in EOCA than in FA. The segregation ratio in EOCA was significantly lower than 0.25. Clinically, EOCA and FA patients presented with a progressive cerebellar syndrome. Associated symptoms, such as muscle wasting, sensory disturbances, foot deformity, scoliosis and electrocardiographic abnormalities were encountered less frequently in EOCA than in FA patients. The electrophysiological findings in EOCA were variable and pointed to axonal degeneration in peripheral nerves and central pathways. Posturographic measurements revealed a higher incidence of anteroposterior sway direction in EOCA as compared with FA, suggesting a cerebellar type of ataxia in EOCA. Eleven out of the 14 EOCA patients had cerebellar atrophy in MRI. The characteristic MRI finding in FA was upper cervical cord shrinkage and only minor atrophy of the cerebellum. The demonstration of cerebellar atrophy in the majority of EOCA patients supports the view that EOCA is distinct from FA. It is uncertain, however, whether EOCA is a homogenous disease entity or a group of phenotypically similar syndromes.
Treatment of blepharospasm and hemifacial spasm with botulinum A toxin: a Canadian multicentre study. Botulinum A exotoxin was recently approved for use in Canada. We describe the efficacy of botulinum toxin in the management of 235 patients with blepharospasm (mean age 64.3 years) and 130 patients with hemifacial spasm (mean age 60.4 years) treated at three Canadian ophthalmologic centres between 1984 and 1989. A total of 98% of the patients with blepharospasm and 100% of the patients with hemifacial spasm had significant relief of their symptoms; however, 11% of the former and 2% of the latter did not respond to the usual starting concentrations of the drug and needed stronger dosages for relief. The duration of relief varied widely in both groups. Up to 7% of patients had ineffective treatments but responded to subsequent injections. Analysis of variance and linear trend statistics showed that there were no changes in the mean duration of relief over the first several treatments for individual patients in either group. Side effects were transient and included ptosis, exposure keratitis, epiphora and strabismus.
Achalasia: current evaluation and therapy. The current evaluation of and therapy for achalasia are reviewed. Esophageal manometry remains the best means for diagnosing achalasia. Initial therapy can include either pneumatic dilation or esophagomyotomy. Symptomatic improvement occurs in 71% of patients after pneumatic dilation, with a risk of perforation of 1.4%. Eight percent of these patients require subsequent esophagomyotomy. Surgical procedures for achalasia can be performed through either an abdominal or a thoracic incision. Nearly all authors favoring an abdominal approach add an antireflux operation to esophagomyotomy, whereas many authors advocating a transthoracic esophagomyotomy believe that an antireflux wrap is unnecessary. Overall results for the various surgical approaches used as initial therapy are excellent, with symptomatic improvement in 89% of patients, a mortality rate of less than 1%, and development of gastroesophageal acid reflux in less than 10%. Factors governing the choice of initial therapy are discussed.
Partial-thickness wedge and advancement flap for upper lip repair Reconstruction of upper lip defects demands careful attention in order to reconstitute both normal function and normal appearance. These defects may involve mucosa, orbicularis oris muscle, skin, vermilion, or any combination of these structures. We will describe five cases in which there were defects created by Mohs micrographic surgery and present the concept of partial-thickness wedge in combination with a flap to repair these wounds.
Treatment of compound fractures. Management of compound fractures remains a challenge to the surgeon. Methods to decrease patient morbidity include early fracture stabilization and sequential debridement. External fixation remains the standard; however, early internal fixation in low-grade injuries may be an acceptable option. Early soft tissue coverage is critical. The use of prophylactic parenteral antibiotics has decreased the incidence of acute infection and chronic osteomyelitis. Supplemental use of local antibiotic polymethyl methacrylate (PMMA) beads appears to further diminish the morbidity in high-grade open fractures.
Chronic osteomyelitis due to Clostridium clostridiiforme. We have reported a case of chronic osteomyelitis due to an unusual anaerobic organism, Clostridium clostridiiforme, a gram-positive rod that often stains gram-negative and that is frequently resistant to such drugs as cefoxitin and clindamycin. Clostridia other than those similar to C perfringens are generally not considered invasive pathogens, but our case and several similar ones show that they can be.
Long-term results and patterns of disease recurrence after radical operations for lung cancer. Long-term results and patterns of disease recurrences after radical operations for lung cancer between 1975 and 1984 were investigated. Eight hundred fifty-two patients (76.1%) with lung cancer underwent operations during this period. Radical operations were performed on 648 patients. There were 326 (50.6%) pneumonectomies, 314 (48.5%) lung resections (lobectomies), and 8 (1.2%) segmentectomies. Long-term survival rates of 542 patients were studied. In 49.2% of the patients survival was beyond 3 years; in 33% of the patients it was beyond 5 years. Five-year survival was observed in 40.3% +/- 2.5% of patients with N1 and in 19% +/- 4.9% of patients with N2 disease. The differences in survival rates between patients with epidermoid cancer and adenocarcinoma were slight and statistically insignificant. The prognosis was poor in patients with small-cell cancer, large-cell cancer, and dimorphous cancer. The causes of death were studied in 193 patients. Disease recurrence was diagnosed in 75.1% of cases. Bronchopulmonary and concomitant diseases accounted for 19.7% of deaths in these patients. In 5.2% of the patients malignant tumors occurred in other organs. Local-regional recurrences were diagnosed in 33.8% of patients, distant metastases occurred in 55.2% of patients, and 11% of patients had combined disease recurrences. The problem of disease recurrence classification is discussed in the article.
Fragile X syndrome: diagnosis using highly polymorphic microsatellite markers. We describe two highly polymorphic microsatellite AC repeat sequences, VK23AC and VK14AC, which are closely linked to the fragile X at Xq27.3. Both VK23AC (DXS297) and VK14AC (DXS292) are proximal to the fragile site. Two-point linkage analysis in 31 fragile X families gave (a) a recombination frequency of 1% (range 0.00%-4%) with a maximum lod score of 32.04 for DXS297 and (b) a recombination frequency of 7% (range of 3%-15%) with a maximum lod score of 12.87 for DXS292. Both of these polymorphisms are applicable to diagnosis by linkage in families with fragile X syndrome. A multipoint linkage map of genetic markers at Xq27.3 was constructed from genotyping these polymorphisms in the CEPH pedigrees. The DXS292 marker is in the DXS98-DXS297 interval and in 3 cM proximal to DXS297.
Grading of human urothelial carcinoma based on nuclear atypia and mitotic frequency. II. Prognostic importance. A grading system was applied in a retrospective study of 124 patients with transitional cell carcinoma of the bladder using a modified Bergkvist system. The intermediate World Health Organization (WHO) grade II tumors were divided into supposedly benign and malignant forms of grades IIa and IIb, respectively. The 5-year survival was 92% for patients with grade IIa urothelial carcinoma, compared to 43% for patients with grade IIb tumors. The corresponding figures for grades I and III tumors were 100 and 44%, respectively. When excluding carcinoma in situ (5-year survival 50%) no patient with a noninvasive tumor (stage Ta) died of bladder carcinoma within 5 years, compared to 50% of those with invasive cancers (stages T1 to T4). We propose a new grading system in which grades I and IIa are embraced as grade A, grades IIb and III as grade B, and grade IV as grade C. The 5-year survival rate in the 3 grades was 94, 44 and 27%, respectively. Grade A seems to represent a type of tumor with universally favorable prognosis, in contrast to grades B and C. This offers practical advantages, since the former can be treated conservatively, whereas the latter need more urgent radical intervention, especially in patients in whom invasive growth is recorded.
Expression of c-jun during macrophage differentiation of HL-60 cells. Cellular transcription factors are important in the regulation of cellular genes. Recent studies have indicated that a class of cellular genes known as early response genes are important in the control of cellular growth properties. Two of these genes, c-jun and c-fos, play an important role in the control of cellular differentiation. Because the acute myelogenous leukemia cell line, HL-60, is capable of differentiating to either macrophages or granulocytes, it provides a good model to understand differential gene expression. To determine if the modulation of c-jun was important in the differentiation of HL-60 cells to either macrophages or granulocytes, expression of c-jun mRNA was determined by Northern analysis at various times following treatment with a variety of differentiating agents, including 12-tetradeconyl-phorbol 13-acetate (TPA), retinoic acid (RA), dimethyl sulfoxide (DMSO), or 1,25 dihydroxyvitamin D3 [1,25 (OH)2 D3]. Both TPA and 1,25(OH)2D3, which induce HL-60 cells to differentiate to macrophages, resulted in marked increases in c-jun mRNA; while RA and DMSO, which induce HL-60 cells to differentiate to granulocytes, did not greatly alter c-jun mRNA expression. HL-60 cell lines resistant to macrophage differentiation after exposure to either 1,25(OH)2D3 or TPA did not result in increases in c-jun mRNA. These results suggest that elevation of c-jun mRNA in HL-60 cells correlated temporally with differentiation to macrophages. Thus, c-jun may be a critical cellular transcription factor involved in macrophage differentiation.
Results of Medical Research Council phase II study of low dose cisplatin and methotrexate in the primary treatment of locally advanced (T3 and T4) transitional cell carcinoma of the bladder. A series of 49 previously untreated patients with category T3 or T4 bladder cancer underwent treatment with low dose methotrexate and cisplatin; 44 patients were eligible for assessment of response. Complete response (CR) was seen in 5 patients (11%) and partial response in 15 (34%) (overall response rate 45%). Treatment was reasonably well tolerated with no major morbidity and no treatment-related deaths. After a median follow-up of 3.5 years, the 1-year and 2-year survival rates were 70 and 30% respectively. Ten patients remain recurrence-free without having received "definitive local therapy" (cystectomy and/or radiotherapy) at follow-up extending from 20 to 50 months.
Complement activation by artificial blood substitute Fluosol: in vitro and in vivo studies. A perfluorocarbon blood substitute, Fluosol, is undergoing clinical trials as an adjunct to chemotherapy. The adverse effects associated with its administration have been postulated to result from complement activation. When gel electrophoresis and Western blotting of Fluosol are used after its incubation with serum, activated C3 and factors Bb and H are bound to the Fluosol particles in a time-dependent fashion, which suggests that complement activation with Fluosol, as does that with zymosan, occurs on the surface of the particles. Paradoxically, it is found, both by the measurement of Fluosol-bound C3d and by fluid-phase C5a, that lower concentrations of Fluosol cause greater amounts of complement activation, which suggests a complex interaction of activators and inhibitors that changes as the available surface area is decreased. Studies performed with bystander red cell-bound C3d demonstrated in vivo complement activation occurring in six patients receiving Fluosol as an adjunct to chemotherapy for colon cancer. In two patients, there was a marked increase in red cell-bound C3d after Fluosol infusion; these two patients also developed adverse reactions during Fluosol infusion. These studies suggest that the Fluosol surface plays a major role in the initiation and regulation of complement activation that is seen during Fluosol infusion.
HMG-CoA reductase inhibitor-induced myopathy in the rat: cyclosporine A interaction and mechanism studies. Recent clinical evidence indicates a potential for skeletal muscle toxicity after therapy with HMG-CoA reductase inhibitors (HMGRIs) in man. Although the incidence of drug-induced skeletal muscle toxicity is very low (0.1-0.2%) with monotherapy, it may increase following concomitant drug therapy with the immunosuppressant, cyclosporine A (CsA), and possibly with certain other hypolipidemic agents. In the Sprague-Dawley rat, very high, pharmacologically comparable dosages (150-1200 mg/kg/day) of structurally similar HMGRIs (lovastatin, simvastatin, pravastatin and L-647, 318) produced dose-related increases in the incidence and severity of skeletal muscle degeneration. Physical signs included inappetence, decreased activity, loss of body weight, localized alopecia and mortality. To evaluate the interaction between HMGRIs and CsA, a rat model of CsA-induced cholestasis was developed. In this 2-week model, the skeletal muscle toxicity of the HMGRIs was clearly potentiated by CsA (10 mg/kg/day). Doses of HMGRIs which did not produce skeletal muscle toxicity when given alone caused between 75 and 100% incidence of myopathy (very slight to marked skeletal muscle degeneration) when CsA was coadministered. Typical light microscopic changes included myofiber necrosis with interstitial edema and inflammatory infiltration in areas of acute injury. Histochemical characterization of the muscle lesion indicated that type 2B fibers (primarily glycolytic white fibers) were most sensitive to this toxicity but that, with prolonged administration, all fiber types were ultimately affected. Results of pharmacokinetic studies in rats treated with various HMGRIs +/- CsA indicated that coadministration of CsA alters the disposition of these compounds, resulting in increased systemic exposure (e.g., increased area under the plasma drug concentration vs. time curve-AUC) and consequent (up to 13-fold) increases in skeletal muscle drug levels. Evaluation of the potential interaction between the HMGRI, lovastatin and CsA at the level of hepatic microsomal metabolism indicated that CsA did not inhibit the metabolism of lovastatin in isolated microsomes from female rats. In light of the above findings, it appears that HMGRI-induced myopathy is a class effect in the rat, which is potentiated by CsA as the result of altered clearance and resultant increased tissue exposure. Cholestasis associated with CsA and HMGRIs may form the basis for decreased elimination and the resultant elevated systemic exposure. Furthermore, this toxicity is muscle fiber-selective and may be associated with impaired skeletal muscle energy metabolism.
Age of onset in siblings concordant for multiple sclerosis. We have evaluated genetic and environmental influences in multiple sclerosis (MS) by comparing age of onset in 99 sibling pairs concordant for the disease. We used three methods of analysis: (1) comparison of mean differences in age of onset and year of onset, (2) linear regression of differences in age or year of onset vs difference in ages, and (3) intraclass correlation of age of onset which is also used for monozygotic twins concordant for MS. Comparison of the mean differences in age of onset or year of onset is found to be inappropriate and potentially misleading. No significant results were found in linear regression of the age of onset or year of onset vs differences in ages, although a trend towards onset at the same age is present. However, nontwin siblings show a significant intraclass correlation for age of onset (P less than 0.01) as is seen in genetic disorders. A stronger intraclass correlation in age of onset in concordant monozygotic twins vs concordant sibling pairs further suggests that age of onset is partly under genetic control, assuming common exposure to an environmental agent. The results give little support for common exposure to an environmental trigger in concordant MS sibling pairs. They are consistent with a mixture of random independent exposures and common exposures leading to the development of the disease, with the former predominating.
A management plan for tongue base cancer that includes brachytherapy. For physiologic as well as oncologic reasons, there has been an increasing interest in radiation therapy as the primary treatment of base of tongue carcinoma. At Memorial Sloan-Kettering Cancer Center, we have used such a plan, using external beam conventional therapy in combination with an interstitial boost of iridium 192 to the primary site, plus planned neck dissections in selected patients. Between 1981 and 1986, 17 patients with untreated base of tongue squamous cell carcinoma were treated in this manner. Thirteen of the 17 are disease-free as a result of this therapy. Two patients have failed locally, yielding an actuarial local control of 87% at a median followup of 2 years. These data would suggest that primary radiation that includes interstitial therapy as part of the plan, along with neck dissection in certain situations, is a worthwhile method management of base of tongue carcinoma.
A double-blind comparison of low-dose intravenous ketamine and methohexital in adults. Two ultralight general anesthetic techniques, one using low-dose ketamine and the other using methohexital as the primary anesthetic agent, were compared for efficacy, safety, and psychomotor recovery in a double-blind fashion for use during third molar surgery. Low-dose intravenous ketamine as the primary anesthetic following premedication with fentanyl and midazolam, and in conjunction with nitrous oxide, appeared to produce less hypoxia, hypercarbia, and apnea than when methohexital was used. No significant differences were noted in heart rate or blood pressure between the techniques. The ketamine technique was universally preferred by the surgeons and anesthesiologists because of superior patient cooperation and airway management. No unpleasant psychomimetic side effects of significance were noted with the use of ketamine. Postoperative recovery took slightly longer in the ketamine group, with patients being judged fit for discharge approximately 10 to 15 minutes later than the patients who received methohexital.
Perioperative respiratory compliance in children undergoing repair of atrial septal defects. Children with atrial septal defects (ASD) have less respiratory compliance (Crs) than normal cohorts. There could be implications for anaesthetic management if these children also have decreased compliance during anaesthesia. To examine the changes in Crs before, during and following surgical correction of the atrial defect, Crs was measured in 29 infants and children, 15 undergoing correction of secundum type atrial septal defects, and a group of 14 children of similar weight undergoing non-thoracic surgery. During sedation, Crs was measured using the single breath technique (SBT) and during anaesthesia, both before and after the surgical procedure, an inflation technique was applied to determine Crs. To investigate the aetiology of the difference in Crs, the pulmonary to systemic flow ratio (Qp:Qs) was determined using echocardiography during sedation in the ASD patients. During sedation, Crs in the ASD group was 52.7 +/- 19.5% less than in the control group. The slope of the line of regression of Crs vs height for the ASD group was significantly less (P less than 0.05) than that of the control group during sedation. However, during anaesthesia, Crs in the ASD group was not significantly different from the control group either before or after surgery. The per cent decrease in Crs during sedation in the children with ASD, in comparison with the control group, did not correlate with the Qp:Qs ratio of the ASD group (r2 = 0.012,NS). We conclude that, in spite of lower Crs during sedation, infants and children with ASD do not have lower Crs during anaesthesia and cardiopulmonary bypass than normal controls undergoing non-thoracic surgery.
Proliferative assessment of GFAP-positive and GFAP-negative glioma cells by nucleolar organizer region staining. The proliferative potential of two types of tumor cells that did or did not express glial fibrillary acidic protein (GFAP) in 19 cases of high-grade gliomas, including nine anaplastic astrocytomas (WHO criteria, grade 3) and 10 glioblastoma multiforme (grade 4), was investigated by a combined staining technique, one-step silver colloid method for nucleolar organizer region-associated argyrophilic protein (Ag-NOR) and immunocytochemistry for GFAP. The mean numbers of Ag-NORs in GFAP-positive cells and GFAP-negative cells of high-grade gliomas were 2.68 and 3.74, respectively. The value of GFAP-negative cells was significantly greater than that of GFAP-positive cells (p less than 0.01). Our results show that, by means of the immunocytochemistry for GFAP, tumor cells in human high-grade gliomas can be divided into two groups expressing GFAP or not, and that the mean number of Ag-NORs of GFAP-negative cells is more representative of the degree of histological malignancy than that of positive cells. It is considered that the proliferative assessment of GFAP-negative tumor cells in high-grade gliomas by combined staining of Ag-NOR silver staining and GFAP immunocytochemistry is useful for understanding the histological malignancy of high-grade gliomas.