123rc/medical_text huggingface dataset:
Cutaneous T-cell lymphoma (parapsoriasis en plaque). An association with pityriasis lichenoides et varioliformis acuta in young children. Pityriasis lichenoides et varioliformis acuta (PLEVA) and pityriasis lichenoides chronica (PLC) are related benign disorders without recognized association with cutaneous T-cell lymphoma (CTCL). We report the cases of two children with documented PLEVA evolving into CTCL over several years. One child had the clinical lesions of PLC but the dermatopathologic findings of PLEVA at age 2 years. At age 12 years, he had skin changes of poikiloderma atrophicans vasculare and dermatopathologic findings consistent with parapsoriasis en plaque. The second child presented at age 7 years with scaling dermatitis and dermatopathologic findings of PLEVA. At age 12 years, the histologic diagnosis was parapsoriasis. Monoclonal antibody studies performed on biopsy specimens from both patients revealed 70% to 100% cells staining with CD5, 80% to 90% staining with CD4, 30% to 50% staining with CD8, and an increase in CD1-staining cells in the papillary dermis, indicating a predominantly helper T-cell infiltrate. We believe that PLC and PLEVA may be part of the spectrum of CTCL. Furthermore, CTCL may be more common in young children than once thought.
A phase I clinical, plasma, and cellular pharmacology study of gemcitabine. A novel deoxycytidine analog, gemcitabine (2',2'-difluorodeoxycytidine [dFdC]), has been studied in a phase I clinical and pharmacology trial. Doses ranging from 10 to 1,000 mg/m2 were administered over 30 minutes weekly times 3 weeks every 4 weeks. The maximum-tolerated dose (MTD) was 790 mg/m2. The dose-limiting toxicity was myelosuppression, with thrombocytopenia and anemia quantitatively more important than granulocytopenia. Nonhematologic toxicity was minimal. Two responses in patients with adenocarcinomas of the colon and lung were documented. The maximum dFdC plasma concentration, reached after 15 minutes of infusion, was proportional to the total dose administered. Elimination, due mainly to deamination, was rapid (terminal half-life [t1/2], 8.0 minutes) and dose independent. The deamination product 2',2'-difluorodeoxyuridine (dFdU) was eliminated with biphasic kinetics characterized by a long terminal phase (t1/2, 14 hours); it was the sole metabolite detected in urine. The concentration of dFdC 5'-triphosphate in circulating mononuclear cells increased in proportion to the dFdC dose at infusions between 35 and 250 mg/m2. No further increment in dFdC 5'-triphosphate (dFdCTP) was observed at higher doses, which resulted in plasma dFdC concentrations greater than 20 mumol/L (350 to 1,000 mg/m2), suggesting saturation of dFdC 5'-phosphate accumulation. The recommended dose for phase II clinical trials in solid tumors is 790 mg/m2/wk.
AIDS enteropathy: occult enteric infections and duodenal mucosal alterations in chronic diarrhea OBJECTIVE: To investigate occult enteric infections and morphologic changes in the small intestine in patients with advanced human immunodeficiency virus (HIV) infection and chronic diarrhea of undefined cause. DESIGN: Case-control study. SETTING: Referral-based clinic and hospital in tertiary care center. PATIENTS: Twenty-two patients with advanced HIV infection (19 with the acquired immunodeficiency syndrome [AIDS], 3 with AIDS-related complex) with chronic diarrhea, selected because of previously negative stool evaluations for bacterial or parasitic pathogens, were compared with 13 patients with advanced HIV infection (9 with AIDS, 4 with AIDS-related complex) without diarrhea by analysis of endoscopic biopsies using light and electron microscopy, viral culture, and morphometric studies. Both groups were convenience samples and had at least 7 months follow-up. MEASUREMENTS AND MAIN RESULTS: Eleven of twenty-two patients with HIV infection and chronic diarrhea but only 1 of 13 patients without diarrhea showed occult enteric pathogens (that is, undetected by routine studies) after extensive evaluation of duodenal and colorectal biopsies. Mycobacterium avium-intracellulare and microsporidia were the most common occult agents in study patients with diarrhea (5 each). Patients with diarrhea and occult enteric infections had greater weight loss (mean, 14.3 kg compared with 6.2 kg; P less than 0.05) and shorter survival (1 of 11 compared with 8 of 11 still alive; P less than 0.004) than those with diarrhea but no identified pathogens (defined as "AIDS enteropathy"). Duodenal morphometry showed decreased villus-to-crypt ratios because of villus atrophy and crypt elongation in HIV-infected patients both with and without diarrhea compared with normal controls (P less than 0.001 for each). All three groups showed comparable frequencies of epithelial mitoses. CONCLUSIONS: Further endoscopic biopsy evaluation of patients with AIDS who had unexplained chronic diarrhea showed an occult infectious cause in half of the cases. However, altered villus and crypt architecture in advanced HIV infection was independent of the presence of diarrhea or enteric infection and therefore did not correlate with AIDS enteropathy. Subnormal epithelial proliferation in response to injury could be a factor, but the underlying cause of the architectural changes remains obscure. We suggest that T-cell dysfunction may play a role.
Transthyretin receptors on human astrocytoma cells. Transthyretin (TTR), a transport protein for T4 and retinol-binding protein, is the principal T4-binding protein of cerebrospinal fluid. Its function in regard to the delivery of its ligands and in other respects is unclear. The binding of [125I] TTR to cultured human astrocytoma cells was studied to determine whether these cells carry receptors for TTR. Scatchard analysis was consistent with a single class of binding sites with a Kd of 3 nM. No significant cross-reactivity with transferrin or serum albumin was observed. Internalization of TTR was temperature dependent and proportional to receptor occupancy. Dilutions of cerebrospinal fluid displaced [125I]TTR in proportion to their content of radioimmunoassayable TTR and in parallel with purified TTR. The uptake and internalization of TTR increased in the presence of high T4 or T3 concentrations. These results demonstrate that TTR binds to specific high affinity receptors on human astrocytoma cells. Receptor binding of TTR provides a potential mechanism for the delivery of its ligands within the central nervous system.
Oral manifestations of HIV infection and their management. I. More common lesions. Oral lesions are common at all stages of HIV infection. This first of two articles reviews the clinical features and pathogenesis of common oral manifestations of HIV disease (candidiasis, hairy leukoplakia, Kaposi's sarcoma, and HIV-related periodontal disease) and considers current treatment measures.
Etoposide in the management of non-small cell lung cancer. Etoposide is a phase-specific, schedule-dependent derivative of podophyllotoxin that appears to act by inhibiting DNA-topoisomerase II. Early preclinical work demonstrated sharp activity in mouse leukemias and possible synergy with cisplatin. As a single agent (either orally or intravenously), it demonstrated limited benefit in non-small cell lung cancer (NSCLC), with response rates around 10%. In combination with cisplatin, it has become a mainstay of chemotherapeutic efforts, either as primary therapy or in conjunction with radiation. Response rates in advanced disease average around 30%, climbing to more than 50% in patients with Stage IIIA or IIIB disease. More recent work suggests that the issue of the true synergy of etoposide with cisplatin in NSCLC needs reassessment. The relative roles of etoposide and cisplatin in the combination are unclear, as several studies conflict. Pharmacokinetic data suggest that multiple daily fractions of etoposide are superior to prolonged infusions, warranting several future trials. The current major role for etoposide plus cisplatin would appear to be in multimodality therapy where the combination can be readily combined with radiation and/or surgery. Several other agents have been studied with etoposide or etoposide plus cisplatin (mitomycin, vindesine, doxorubicin, cyclophosphamide, ifosfamide, and carboplatin), but it is unclear whether the addition of any of them offers any response or survival advantage.
Regulation of the truncation of luteinizing hormone receptors at the plasma membrane is different in rat and mouse Leydig cells. Regulation of the truncation of LH receptors was investigated in two types of mouse tumor Leydig cells (MA10 and MLTC-1), rat testis Leydig cells (RTL), and a rat tumor Leydig cell (R2C). Receptor numbers were measured by binding [125I]hCG to the cells cultured in monolayers. Addition of 3.3 nM LH for 2 h at 34 C had no detectable effect on binding sites in RTL or R2C cells, but in MA10 and MLTC-1 cells it caused a loss in binding sites. The effect on MA10 and MLTC-1 cells could be mimicked by inhibiting receptor internalization with 5 mM NaN3 and prevented by the addition of protease inhibitors. Incubating RTL and R2C cells with protease inhibitors caused a 2- to 3-fold increase in binding sites and a 2- to 3-fold increase in LH (0.033 and 0.33 nM)-stimulated cAMP production. When RTL and MA10 cells were incubated in the presence of [125I]hCG, a radioactive protein complex with an approximate mol wt of 80,000-90,000 was released into the incubation medium. We conclude that LH receptors are regulated by proteolysis at the plasma membrane in both mouse and rat Leydig cells. Furthermore, truncation of the LH receptor in the mouse Leydig cells is involved in down-regulation, whereas in the rat it is a continuous process.
Premenstrual syndromes defined by symptom-sets. An analysis is made of the pattern of presenting premenstrual symptoms in randomly selected general practice patients from the Wellington region, New Zealand. Participants, 1826 healthy women 16-54 years old whose characteristics were reasonably representative of the adult female population, were asked about their general, obstetrical and gynaecological health. For the 1456 women who had menstruated within the last month or so, detailed questions were asked about the last menstrual cycle. Each woman was assigned to one of seven premenstrual symptom sets. Three groups had 'pure' symptoms, ie a predominant single symptom (breast tenderness, bloating or irritability). Three groups had 'mixed' symptom-sets. The largest of the 'mixed' groups was formed by the women who reported breast tenderness, bloating and irritability together with tension and depression. Women in this group were most likely to rate their symptomatology as severe. The last group contains a large number of women with miscellaneous symptoms. Characteristics of these groups are outlined. The study highlights the importance of distinguishing among premenstrual syndromes as this can foster more effective clinical management.
Bilateral phrenic nerve palsy associated with open-heart surgery. The incidence of phrenic nerve palsy after open-heart surgery has been estimated at 10%, but it is usually unilateral and does not cause symptoms. Bilateral phrenic nerve injury after coronary artery bypass surgery is a rare complication. This case report describes a patient who developed bilateral phrenic nerve palsies and required prolonged ventilatory support. Denervation of both hemidiaphragms was documented by needle electromyography four weeks after bypass surgery. The patient required total ventilatory support for three months and partial ventilatory support for an additional three months. This case demonstrates the usefulness of electromyographic screening for documentation and prognostication after phrenic nerve injury. The cause of the lesion was unclear, but hypothermia and stretch were leading hypotheses. This patient developed the phrenic nerve palsies despite using a cardiac insulation pad.
Nevus flammeus. Discordance in monozygotic twins. Nevus flammeus has been described as an inherited vascular anomaly. We report two cases of nevus flammeus, each appearing in one of two monozygotic twins. This finding supports the idea that nevus flammeus results from embryologic mishap rather than genetic transmission.
Idiopathic intracranial hypertension. A prospective study of 50 patients. Management of patients with idiopathic intracranial hypertension (IIH) should be based on the presence and progression of visual loss. To characterize the clinical course of IIH more completely, we monitored the clinical status, especially visual function, in 50 consecutive newly-diagnosed patients over a period of 2 to 39 months (average follow-up 12.4 months). The mean age at onset of symptoms was 31 (range 11-58) yrs; 46 (92%) were women and 47 (94%) were obese (mean weight 90 kg). Common symptoms were headache (92%), transient visual obscurations (72%) and intracranial noises (60%); 13 of the patients (26%) initially had complaints of sustained visual loss. There was visual loss as determined by Goldmann perimetry in 96% and by automated perimetry in 92%. Contrast sensitivity testing was abnormal in 50% and Snellen acuity in 22%. Two patients (4%) became blind in both eyes. The Goldmann visual field grade improved in 60% of patients but visual function deteriorated in 5 (10%). Deterioration of visual field grade was significantly associated only with weight gain during the year before diagnosis. Visual loss in patients with IIH is common and is often reversible. Patients should be evaluated by perimetry using an appropriate strategy and contrast sensitivity testing, along with careful examination of the optic discs.
Effects of epidural anesthesia on the incidence of deep-vein thrombosis after total knee arthroplasty [published erratum appears in J Bone Joint Surg [Am] 1991 Jul;73(6):952] Epidural anesthesia has been reported to reduce the prevalence of deep-vein thrombosis after total hip arthroplasty compared with the prevalence after general anesthesia. However, the effect of epidural anesthesia on the rate of thrombosis after total knee arthroplasty has not been reported previously, to our knowledge. A review was conducted of 705 total knee arthroplasties (541 patients) that had been performed by a single surgeon between September 1984 and December 1988. During this period, the operative technique, the protocol for rehabilitation, and the regimen for prophylaxis against thromboembolism did not change meaningfully. The patients received either epidural or general anesthesia. Preoperative and postoperative perfusion scans of the lungs and a venogram of the lower limb or limbs that had been operated on were done for all patients. For the 227 patients who had received epidural anesthesia, the over-all rate of deep-vein thrombosis was 48 per cent, which was significantly lower than the 64 per cent incidence in the 264 patients who had received general anesthesia (p less than 0.0001). The greatest reduction was in the occurrence of proximal thrombosis, which was identified in 9 per cent of the patients who had had general anesthesia but in only 4 per cent of those who had had epidural anesthesia (p less than 0.05). The use of epidural anesthesia reduced the incidence of proximal thrombosis after both unilateral and one-stage bilateral arthroplasty.
Internuclear ophthalmoplegia in the Chiari type II malformation. We describe 3 cases of Chiari type II malformation presenting with bilateral internuclear ophthalmoplegia (INO). Although prominent, the INO was not an isolated sign in any of the patients; superimposed abduction paresis was present in 2, and deficits in smooth pursuit, optokinetic nystagmus, and vestibulo-ocular responses were present in 3. Two had hydrocephalus: 1 was clinically unchanged without therapy after 5 years; the other did not improve with shunting. Findings in our 3 patients, along with the 4 previously reported, confirm that INO is 1 manifestation of widespread brainstem or cerebellar dysfunction. Its origin is probably multifactorial, related to hydrocephalus, vascular compromise, direct neuronal distortion, or congenital neural malformation.
Repair of O6-ethylguanine in DNA protects rat 208F cells from tumorigenic conversion by N-ethyl-N-nitrosourea. O6-Ethylguanine (O6-EtGua) is one of about a dozen different alkylation products formed in the DNA of cells exposed to the alkylating N-nitroso carcinogen N-ethyl-N-nitrosourea (EtNU). We have evaluated selectively the relative capacity of cells for the specific enzymatic repair of O6-EtGua as a determinant for the probability of malignant conversion. Eleven O6-EtGua-repair-proficient (R+) variant subclones were isolated from the O6-EtGua-repair-deficient (R-) clonal rat fibroblast line 208F by selection for resistance to 1,3-bis-(2-chloroethyl)-1-nitrosourea (frequency, approximately equal to 10(-5). Contrary to the 208F wild-type cells, all variants expressed O6-methylguanine-DNA methyltransferase activity, while both kinds of cells were deficient for repair of the DNA ethylation products O2- and O4-ethylthymine. After exposure to EtNU (less than or equal to 500 micrograms/ml; 20 min), cells were analyzed for the formation of piled-up foci in monolayer culture and of anchorage-independent colonies in semisolid agar medium. Depending on the EtNU concentration, the frequencies of piled-up foci and agar colonies, respectively, in the R+ variants were as low as 1/28th and 1/56th of those in the R- wild type. Contrasting with the cells from R+ variant-derived agar colonies, cells from 208F (R-) agar colonies gave rise to highly malignant tumors when implanted subcutaneously into syngeneic rats. No significant differences in the frequencies of piled-up foci were found between wild-type and variant cells after exposure to the major reactive metabolite of benzo[a]pyrene, (+)-7 beta, 8 alpha-dihydroxy-9,10 alpha-epoxy-7,8,9,10 alpha-tetrahydrobenzo[a] pyrene, for which stable binding to guanine O6 in cellular DNA has not been observed. The relative capacity of cells for repair of O6-alkylguanine is, therefore, a critical determinant for their risk of malignant conversion by N-nitroso carcinogens.
Recurrence of resected esophagogastric adenocarcinoma: results of re-resection. Isolated local recurrence following potentially curative resection for carcinoma of the esophagus or esophagogastric junction does not necessarily imply pending systemic disease and early demise. While radiation alone or in combination with chemotherapy is standard treatment for such patients, resection is another available option. Resection may also be a consideration should localized disease persist after non-operative therapy in the absence of metastases. A 5 year retrospective review was performed examining 204 resections performed prior to 1989. Only 5 patients underwent resection of locally recurrent esophagogastric (EG) adenocarcinoma during this period. No squamous carcinoma recurrences were resected. One patient is well 15 months later while another died at 18 months of other causes without recurrence. Recurrence after re-resection occurred at 8, 11, and 24 months in the 3 other patients. Although there were no postoperative deaths, major complications occurred in 4 patients. All 5 patients swallowed normally after operation.
Sucralfate used as adjunctive therapy in patients with severe erosive peptic esophagitis resulting from gastroesophageal reflux. A total of 36 patients with grade 2 or greater erosive esophagitis and an abnormal 24-h pH monitor study, were treated in a randomized, double-blind fashion to assess the efficacy of sucralfate suspension as adjunctive therapy to cimetidine for severe esophagitis secondary to gastroesophageal reflux. Treatment consisted of cimetidine, 300 mg qid and either sucralfate suspension (1 g/10 ml) or an identical placebo suspension, 10 ml after meals and 20 ml hs. Patients were treated for 12 wk unless endoscopic healing occurred earlier. Initial evaluation and monthly follow-up consisted of symptom monitoring, endoscopic evaluation and pre- and post-therapy esophageal manometry, Bernstein test, and 24-h pH monitoring. The combination of cimetidine and sucralfate suspension was superior to cimetidine alone in improving daytime heartburn symptoms (p less than 0.05) but not nighttime heartburn, dysphagia, or regurgitation. Sucralfate plus cimetidine improved the overall endoscopic outcome of esophagitis more than cimetidine alone (p less than 0.05). More patients exhibited endoscopic healing in the adjunctive sucralfate group than in the cimetidine-only group. Endoscopic healing, however, was not statistically different between groups. We conclude that sucralfate used as adjunctive therapy to cimetidine resulted in improvement of some of the symptoms of reflux, and probably increases the likelihood of complete healing of esophagitis, compared with cimetidine alone.
Antibodies to Epstein-Barr virus in iridocorneal endothelial syndrome. Antibody titers to Epstein-Barr virus were determined in 13 patients with iridocorneal endothelial syndrome and in 13 healthy race-, age-, and sex-matched controls. Both the geometric mean titer of IgG antibodies to the Epstein-Barr virus capsid antigen and the proportion with high titers of IgG antibodies to the Epstein-Barr virus capsid antigen (greater than or equal to 1:640) were significantly higher in 12 seropositive patients with iridocorneal endothelial syndrome than in 12 seropositive controls (1/761:1/202, P = .001; 83.3%:8.3%, P less than .001). Ten of 12 seropositive patients with iridocorneal endothelial syndrome and five of 12 seropositive controls had antibodies to Epstein-Barr virus-induced early antigens (greater than or equal to 1:10) (Fisher's Exact Test, P less than .05), while four seropositive patients with iridocorneal endothelial syndrome and one seropositive control had low to undetectable levels of antibodies to Epstein-Barr virus-associated nuclear antigen (less than or equal to 1:5) (P greater than .1). Antibody levels to cytomegalovirus or measles virus were not different between patients with iridocorneal endothelial syndrome and controls. Additional studies showed no evidence of humoral immune disorder or collagen vascular disease in the patients with iridocorneal endothelial syndrome. The serologic profiles suggest that the patients with iridocorneal endothelial syndrome examined had a cellular immune abnormality sufficient to permit reactivation of latent Epstein-Barr virus infection and imply, but do not establish, a role for Epstein-Barr virus infection in the pathogenesis of some cases of the iridocorneal endothelial syndrome.
Use of the levator scapulae muscle flap in head and neck reconstruction. There are numerous techniques available for reconstruction of defects following composite resection of oral cavity and oropharyngeal tumors. No single technique is applicable in all situations. The levator scapulae muscle flap is well known for its application in carotid protection. Little attention is paid to its usefulness in other aspects of head and neck reconstruction. We have been using the levator scapulae muscle flap for a variety of reconstructive problems. The flap is useful for buttressing intraoral suture lines, closing intraoral defects, and providing soft tissue to fill in dead spaces and bulk out lateral and anterior oral defects. The levator flap was found to be easy to elevate, safe, and reliable with a minimum of wound complications. A review of 18 patients, representative case studies, and a discussion of surgical technique and relevant anatomy and blood supply is presented.