Melricflash/CW_MedAbstractsAlt huggingface dataset:
Effects of the differentiating agent hexamethylene bisacetamide on normal and myelodysplastic hematopoietic progenitors. Hexamethylene bisacetamide (HMBA; NSC 95580) is a potent polar-planar differentiating agent of leukemia and solid tumor cell lines in vitro at clinically achievable concentrations. HMBA is currently being studied in patients with myelodysplastic syndrome. Previous phase I trials have demonstrated that HMBA produces hematologic toxicity in morphologically normal bone marrows of patients with solid tumors. Because of concern that HMBA may produce more severe myelotoxicity in patients with myelodysplastic syndrome since these patients have limited hematopoietic reserves, we studied the effects of HMBA on myelodysplastic and normal hematopoietic progenitors in vitro. HMBA concentrations that are optimal for differentiation in vitro (2 to 5 mmol/L) and HMBA concentrations that are being achieved in clinical trials (1 to 2 mmol/L) inhibited the growth of granulocyte-macrophage colony-forming units and erythroid burst-forming units from all 15 patients with myelodysplastic syndrome and all 4 normal subjects, HMBA did not induce proliferation of myelodysplastic or normal progenitors at any concentration; rather, it produced nearly identical inhibition of normal and myelodysplastic hematopoietic progenitors. HMBA also produced quantitatively similar inhibition of clonogenic leukemic growth of two myeloid leukemia cell lines. For a differentiating agent to be effective, it will likely have to either produce both differentiation and proliferation of abnormal hematopoietic progenitors or show selective inhibitory effects on abnormal as compared with normal progenitors. Although the mechanisms responsible for the antiproliferative effects of HMBA cannot be determined from this study, similar inhibitory effects of HMBA on normal and abnormal hematopoietic progenitors suggest that HMBA may be of limited utility in producing and sustaining elevations of peripheral blood cell counts in patients with myelodysplastic syndrome. 

Category: general pathological conditions
Factor XIIIa in nodular malignant melanoma and Spitz naevi. The distribution of factor XIIIa-positive dermal dendritic cells was studied in a series of nodular malignant melanomas and compared with that seen in Spitz naevi. Two patterns of distribution were recognizable: (a) diffusely spread through the tumour and (b) located mainly at the periphery of the tumour. These did not correlate with the diagnosis of melanoma or Spitz naevus and the distribution appeared to be a function of growth pattern of the tumour. The diffuse pattern was the most common regardless of diagnosis and the distribution of factor XIIIa-positive cells is the same in malignant melanoma and Spitz naevi. 

Category: neoplasms
Flow cytometric analysis of the mechanism of methylmercury cytotoxicity. Flow cytometric analysis of murine erythroleukemic cells (MELC) exposed in vitro to 2.5 to 7.5 mumol/l (micromolar) methylmercury (MeHg) reveals a dose-dependent decrease in the rate of DNA synthesis (rate of passage through the S phase of the cell cycle), manifested as the accumulation of most of the cells in the S phase, and a modest accumulation of cells in the G2/M phase of the cycle. Light microscopy reveals a progressive increase in chromosomal damage (condensation, pulverization). At or above 10 mumol/l MeHg, progression through all the phases of the cell cycle is blocked and mitotic cells are arrested irreversibly in anaphase, with most exhibiting arrangement of chromosomes in a wreathlike ring formation. Also the cells exhibit both nuclear propidium iodide (PI) fluorescence (indicative of loss of viability) and concurrent cytoplasmic carboxyfluorescein (CF) fluorescence (viable cells exhibit CF fluorescence and exclude PI). In addition, there is a dose-dependent increase in cellular refractive index (90 degrees light scatter), an apparent decrease in cell volume (axial light loss), and progressive resistance to detergent (NP-40)-mediated cytolysis. Resistance to detergent-mediated cytolysis is indicative of fixation (protein denaturation, cross-linking, and so on) of the plasma membrane/cytoplasm complex. Our findings indicate that DNA synthesis is the primary target of MeHg cytotoxicity and that apparent targets and degree of cytotoxicity are a complex function of dose. 

Category: general pathological conditions
Differences between florid osseous dysplasia and chronic diffuse sclerosing osteomyelitis. Florid osseous dysplasia (FOD) is confused in the literature with chronic diffuse sclerosing osteomyelitis. Two cases of each condition are presented to demonstrate the differences between them. In FOD, there are multiple lobulated sclerotic masses in several quadrants of the jaws, usually in black females. In some cases, the sclerotic masses are exposed to the oral cavity, resulting in a secondary osteomyelitis. Periapical cemental dysplasia is often found in association with FOD. Chronic diffuse sclerosing osteomyelitis is a primary inflammatory condition of the mandible. Patients have cyclic episodes of unilateral pain and swelling. The affected region of the mandible exhibits a diffuse opacity with poorly defined borders. Although women are affected more often than men, black persons are not particularly susceptible. 

Category: general pathological conditions
The modified Schollner costoplasty. The modified Schollner costoplasty is a cosmetic procedure for the correction of rib prominence deformity in scoliosis. We present the results of the procedure in 21 patients who had previously undergone spinal fusion for scoliosis. We found the procedure to be well tolerated without major complications. Objective cosmetic improvement was achieved in all but one case. All but one patient considered the procedure to have been of cosmetic benefit. 

Category: nervous system diseases
The hyperimmunoglobulinaemia E and recurrent infections syndrome in an adult [published erratum appears in Thorax 1990 Dec;45(12):984] A 27 year old white woman with a history of chronic eczema and episodes of serious infection of the chest, skin, and bone presented with acute respiratory failure. She was found to have a spontaneous right pneumothorax and a pneumatocele in the left upper lobe. Despite a left upper lobectomy she was left with chronic respiratory failure, bullous lung disease, and bilateral bronchiectasis. The hyperimmunoglobulinaemia E and recurrent infections syndrome was diagnosed only in adult life. 

Category: general pathological conditions
Pre-discharge immunization among hospitalized Filipino children. Identifying opportunities to vaccinate eligible children is one way to boost rates of immunization especially in countries with low immunization coverage and where convalescence from infectious illness is a contraindication to vaccination. To determine the safety and immunogenicity of diphtheria-tetanus toxoid-pertussis and oral polio immunization, 210 convalescing infants and children and community controls, comparable image and nutritional status, were studied. Using the pertussis agglutination and poliovirus neutralization tests, quantitative serologic responses were compared in the two study groups. No significant differences in the incidence rates of febrile reactions (23% in controls; 28% in convalescents) of local reactions (92% in controls; 87% in convalescents) and of seroconversion (P greater than 0.05) were noted between the two groups. Our investigation suggests that infants and children convalescing from infectious illnesses can be safely and effectively vaccinated. This study further suggests that hospitalization provides an opportunity to vaccinate such children. 

Category: general pathological conditions
Post-transplant hypertension. Post-transplant hypertension remains an important risk factor for cardiovascular mortality and graft function. There are multiple mechanisms responsible for post-transplant hypertension. The details of these mechanisms are poorly understood. Steroids, acute and chronic rejection, recurrent renal disease, native kidney disease, and renal artery stenosis have all been implicated in causing post-transplant hypertension. With the addition of cyclosporine, a known hypertensive agent, to the immunosuppressive armamentarium, the evaluation of post-transplantation hypertension has become difficult. Presently, medical therapy is initially directed toward the complications of cyclosporine nephrotoxicity. Empirically, converting enzyme inhibitors are added to the antihypertensive regimen. Further management is aimed at identification of specific causes of post-transplant hypertension. Unfortunately, because of the multifactorial etiology of post-transplant hypertension and a lack of detailed information about the mechanisms, medical and surgical therapy are often unrewarding. Further study is needed to clarify the mechanisms involved in post-transplant hypertension, and thus direct therapy. 

Category: cardiovascular diseases
Potentiation of the erythropoietin response by dimethyl sulfoxide priming of erythroleukemia cells: evidence for interaction of two signaling pathways. Erythropoietin (Epo) and dimethyl sulfoxide (DMSO) are believed to induce the differentiation of transformed erythroid cells by different signal transduction pathways. We have now obtained evidence for the interaction of these pathways. We used a Rauscher murine erythroleukemia cell line with a relatively low (8% to 10%) hemoglobinization response to Epo alone. Pretreatment of these cells for 1 day with DMSO followed by its removal and the addition of Epo resulted in a marked enhancement of the Epo specific hemoglobinization. We have designated this effect "DMSO priming." This priming effect of DMSO on the Epo response was both time-dependent and DMSO concentration-dependent. DMSO priming potentiated the Epo response in three ways. Firstly, DMSO priming increased the total number of Epo responsive cells from 8% to 10% to 40% to 60%. Secondly, DMSO priming reduced the time required to reach the optimal Epo-induced response from 4 days to 2 days. Thirdly, the Epo dose-response curve was left-shifted approximately 20-fold. DMSO priming was also associated with a marked increase in Epo receptor density characterized by an apparently new receptor population and by the appearance of positive cooperativity between receptors. Our results suggest that the DMSO priming effect is due to potentiation of the Epo signaling pathway, thus resulting in a much more rapid and dramatic Epo-induced hemoglobinization response. 

Category: neoplasms
Effect of sleep-induced increases in upper airway resistance on respiratory muscle activity. To investigate the response of inspiratory and expiratory muscles to naturally occurring inspiratory resistive loads in the absence of conscious control, five male "snorers" were studied during non-rapid-eye-movement (NREM) sleep with and without continuous positive airway pressure (CPAP). Diaphragm (EMGdi) and scalene (EMGsc) electromyographic activity were monitored with surface electrodes and abdominal EMG activity (EMGab) with wire electrodes. Subjects were studied in the following conditions: 1) awake, 2) stage 2 sleep, 3) stage 3/4 sleep, 4) CPAP during stage 3/4 sleep, 5) CPAP plus end-tidal CO2 pressure (PETCO2) isocapnic to stage 2 sleep, and 6) CPAP plus PETCO2 isocapnic to stage 3/4 sleep. Inspired pulmonary resistance (RL) at peak flow rate and PETCO2 increased in all stages of sleep. Activity of EMGdi, EMGsc, and EMGab increased significantly in stage 3/4 sleep. CPAP reduced RL at peak flow, increased tidal volume and expired ventilation, and reduced PETCO2. EMGdi and EMGsc were reduced, and EMGab was silenced. During CPAP, with CO2 added to make PETCO2 isocapnic to stage 3/4 sleep, EMGsc and EMGab increased, but EMGdi was augmented in only one-half of the trials. EMG activity in this condition, however, was only 75% (EMGsc) and 43% (EMGab) of the activity observed during eupneic breathing in stage 3/4 sleep when PETCO2 was equal but RL was much higher. We conclude that during NREM sleep 1) inspiratory and expiratory muscles respond to internal inspiratory resistive loads and the associated dynamic airway narrowing and turbulent flow developed throughout inspiration, 2) some of the augmentation of respiratory muscle activity is also due to the hypercapnia that accompanies loading, and 3) the abdominal muscles are the most sensitive to load and CO2 and the diaphragm is the least sensitive. 

Category: general pathological conditions
Epidemiology of pelvic inflammatory disease in parous women with special reference to intrauterine device use. Up to the end of 1989, 206 parous women in the Oxford Family Planning Association contraceptive study had been referred to hospital with a first episode of pelvic inflammatory disease. Of these, 65 suffered from definite disease described as acute, 81 from definite disease not described as acute and 60 from 'other disease'. Considering all forms of disease together, referral was less common in those aged 25-29 and in those aged 45 or more than in those aged 30-44. Referral was more common in those of low social class, in those who smoked and in those who married young. All these factors were taken into account in analyses considering the effects of contraceptive methods. In these analyses, women currently using the contraceptive pill, the diaphragm, the sheath, female sterilization or an intrauterine device (IUCD) were compared with those currently using other methods or no method of contraception. IUCD ex-users were, however, placed in a separate category, irrespective of their current method of contraception. The relative risks obtained in these analyses, with 95% CI, were as follows: contraceptive pill 0.5 (0.2-0.9), diaphragm 0.6 (0.3-1.2), sheath 1.2 (0.6-2.4), female sterilization 0.7 (0.3-1.5), non-medicated IUCD 3.3 (2.3-5.0), medicated IUCD 1.8 (0.8-4.0), IUCD ex-users 1.3 (0.7-2.3). These data suggest that oral contraceptives, the diaphragm and female sterilization protect against pelvic inflammatory disease and that IUCDs increase the risk. Medicated devices, however, appear to carry only about half the risk of non-medicated devices, and the elevation of risks in IUCD ex-users appears to be small. Special analyses examined the risk associated with use of a Dalkon Shield. Among women currently using an IUCD (of any kind), those who had used a Dalkon Shield (at any time) had nearly five times as great a risk of hospital referral for pelvic inflammatory disease as those who had never used a Dalkon Shield (relative risk 4.7, 95% CI 2.1-9.0). 

Category: general pathological conditions
Hereditary ovarian cancer. Heterogeneity in age at diagnosis. An unknown fraction of the ovarian cancer burden occurs in women with a family history indicative of a putative autosomal dominantly inherited cancer susceptibility syndrome. The results from a five-generation, extended, hereditary breast-ovarian cancer kindred are described 10 years after it was initially ascertained. Significantly more cancers were observed in high-risk family members during this decade than were expected (P less than 0.001). The age of ovarian cancer diagnosis was studied in additional ovarian cancer-prone families of three types: site-specific ovarian cancer syndrome, the breast-ovarian cancer syndrome, and Lynch syndrome II. The age of onset in each of the three sets was significantly (P less than 0.001) earlier than the general population mean of 59, and there were significant differences in the age of onset (P = 0.050) among these three cohorts. Ovarian cancer histology was similar to that of patients with negative family histories. There may be clinically significant heterogeneity in the age at diagnosis of ovarian cancer among these ovarian cancer-prone syndromes. This has important implications for understanding its natural history and targeting surveillance-management strategies. 

Category: general pathological conditions
The influence of warning signal timing and cognitive preparation on the aversiveness of electric shock. Many medical and dental procedures are noxious. Finding an optimal way of warning patients concerning the aversive procedures could help them to cope better. A model for the effective use of a warning signal in coping with pain posited that a person needs enough time to be able to react and should possess the skills necessary to utilize the time effectively. It was felt that a very short warning period, e.g., 5 sec, could not be long enough, while a 180 sec warning period would in and of itself become aversive. Reactions to electric shock were obtained from 36 paid, volunteer subjects who were each tested on a within-subject, counterbalanced order at 4 different warning periods: 5, 30, 60, and 180 sec. The subjects were divided into 3 groups: (1) the experimental group was provided with a pretested self-instructional booklet to learn a variety of pain control techniques; (2) the placebo group was provided with a self-instructional booklet on citizenship; (3) the control group waited quietly for 13 min. No significant results were obtained for the different pain-coping conditions. Significant differences, however, were obtained for the various warning periods. Maximum skin resistance changes, higher ratings of pain and of anxiety were obtained for the 60 and 180 compared to the 5 and 30 sec warning periods. Maximum heart rate was obtained for the 30 sec warning. Results were discussed in terms of the psychological meaning of the various measures as well as their clinical implications. 

Category: nervous system diseases
Endothelium-dependent responses in long-term human coronary artery bypass grafts. In the present study, responses of long-term human coronary artery bypass grafts (CABGs) to known endothelium-dependent vasodilators, acetylcholine, calcium ionophore A23187, thrombin, and histamine, as well as authentic nitric oxide, the putative endothelium-derived relaxing factor, were studied. Sixteen CAGBs were isolated within 1-2 hours from hearts of 14 patients receiving a cardiac transplant. A total of 109 ring segments were prepared from these CABGs and studied in vitro. The duration of the CABGs ranged from 7 months to 12 years. Addition of acetylcholine (0.01-10 microM), calcium ionophore A23187 (0.01-1.0 microM), thrombin (0.01-1.0 unit/ml), and histamine (0.01-1.0 microM) consistently produced a dose- and endothelium-dependent relaxation, reaching a maximum of -35.3 +/- 3.3%, -45.3 +/- 5.5%, -26.9 +/- 4.8%, and -17.8 +/- 2.5% (mean +/- SEM), respectively. No significant difference was observed among the CABGs with different duration of transplantation, whereas the relaxant responses of different segments along the entire length of a CABG were markedly different. These latter differences in the endothelium-dependent responses appear to correlate inversely with the development of intimal proliferative lesions in these CABGs. Addition of nitric oxide (0.01-10 microM) produced a potent dose- and endothelium-independent relaxation, which was also slightly depressed in CABGs with severe intimal proliferation. These results demonstrate that long-term transplanted human saphenous vein grafts retain their endothelium-dependent responses and that development of severe intimal proliferative lesions, rather than the duration of the grafts, result in marked alterations in the reactivity of these transplanted CABGs. 

Category: general pathological conditions
Comparison of blood flow assessment between laser Doppler velocimetry and the hydrogen gas clearance method in ischemic intestine in dogs. Blood flow of the colon and the ileum was measured before and after intestinal devascularization by laser Doppler velocimetry and the hydrogen gas clearance technique in 10 dogs in order to evaluate the clinical usefulness of laser Doppler velocimetry. The submucosal blood flow of the colon and the ileum measured by the hydrogen gas clearance method was significantly decreased, as was the subserosal blood flow of both sites measured by laser Doppler velocimetry. There was a linear relationship between the flow values using the two methods both in the colon (r = 0.7192, p less than 0.001) and in the ileum (r = 0.7646, p less than 0.001). These data suggested laser Doppler velocimetry may be a useful method to assess the degree of intestinal ischemia because of its noninvasiveness and good correlation with submucosal blood flow by the hydrogen gas clearance technique. 

Category: cardiovascular diseases
Reciprocal inhibition between forearm muscles in spastic hemiplegia. We studied reciprocal inhibition of H-reflexes in the forearm flexor and extensor muscles in 14 patients with spastic hemiplegia secondary to a focal cerebral lesion and 14 normal volunteers. In the spastic limb, the Hmax/Mmax ratio was increased in both flexor and particularly extensor wrist muscles. The 3 normal inhibitory phases of reciprocal inhibition between extensor and flexor forearm muscles were markedly reduced on the spastic side of patients. The early disynaptic phase showed the greatest alteration. Reduced or absent inhibition between forearm muscles associated with increased spinal motoneuron excitability may be typical to spastic hemiplegia. 

Category: nervous system diseases
Computerized tomography as an indicator of isolated mesenteric injury. A comparison with peritoneal lavage. This study evaluated 18 patients with blunt abdominal trauma who suffered isolated mesenteric injuries, diagnosed at exploratory laparotomy. Thirteen had diagnostic peritoneal lavage (PL) as their initial diagnostic study, and five had computed tomography (CT). All patients who had positive PL were explored emergently, undergoing repair of mesenteric injuries. Three of the five patients with CT as initial studies had delayed recognition of their injuries due to incorrect initial interpretation of the scan in two, and a false negative scan in one. Two of these patients developed intestinal infarction and required bowel resection. There were no complications in the PL group related to surgery; morbidity was greater in those undergoing CT. We conclude that early laparotomy and repair of significant mesenteric injuries is necessary to reduce morbidity, and that PL is a more sensitive indicator of this injury than CT. 

Category: general pathological conditions
A prospective study of double diagnosis of nonpalpable lesions of the breast. Approximately three-fourths of open biopsies of the breast performed for mammographically detected suspicious lesions are shown histologically to be benign. Under the narrow conditions described herein, stereotaxic fine-needle aspiration (FNA) can identify these lesions with an accuracy of more than 90 per cent and a false-negative rate of 5 per cent. In an effort to reduce this failure rate, the mammographic appearance and stereotaxic FNA results of these lesions each were given scores on a scale of zero (benign) to five (malignant), to derive an over-all risk score prospectively applied to 264 suspicious occult lesions of the breast prior to open, biopsy. While all 264 lesions could be assigned a mammographic score, adequate tissue for assignment of a cytologic score could be obtained from 150 lesions. Of the 150 evaluable lesions, 53 were malignant and 97 were benign, historically. With a total score of two as the threshold for open biopsy, 21 of 150 (14 per cent) were proved to be benign, with no false-negative findings. If the total threshold score mandating an open biopsy was raised to four, the comparable figures were 61 of 150 (40 per cent) benign lesions and two false-negative instances of carcinoma in situ. Provided adequate tissue is aspirated for cytologic examination, we conclude that this algorithm has practical value in the management of nonpalpable lesions of the breast in that it can reliably identify a fraction of the benign lesions and spare these patients an operation. 

Category: neoplasms