Biomedical subjects
Publications and source records attributed to D A Bell.
An incipient form of tongue projection occurs in Phrynocephalus helioscopus, a generalized agamid lizard. We argue that this condition represents a functional intermediate between typical lingual prehension and chamaeleontid tongue projection, and that tongue projection evolved in chameleons by augmentation of ancestral mechanisms still operating in related, generalized lizards.
Forty-two patients with primary fibromyalgia were randomized into a 20-week program consisting of either cardiovascular fitness (CVR) training or simple flexibility exercises (FLEX) that did not lead to enhanced cardiovascular fitness. Patients were supervised by the same medical fitness instructors. Patients in neither group had contact with members of the other group, and were blinded as to the exercise taught to the alternative group. Groups met for 60 minutes 3 times each week. The compliance rate was 90%. Thirty-eight patients completed the study (18 with CVR training and 20 with FLEX). Blind assessments (standardized in preliminary trials to achieve acceptable inter-rater agreement) were performed by the same 2 examiners. After 20 weeks, patients receiving CVR training showed significantly improved cardiovascular fitness scores compared with those receiving FLEX training (t[35] = -4.22, P less than 0.003). Logistic regression analysis showed clinically and statistically significant improvements in pain threshold scores, which were measured directly over fibrositic tender points, in patients undergoing CVR (t[35] = 2.21, P less than 0.04). There was also a trend toward improvement in pain scores (visual analog scale) in the CVR group, but this did not reach statistical significance. There was no improvement in the percentage of body area affected by fibrositic symptoms or the number of nights per week or hours per night of disturbed sleep (self-report inventories). However, compared with the FLEX group, the CVR-trained patients improved significantly in both patient and physician global assessment scores.(ABSTRACT TRUNCATED AT 250 WORDS)
Germinal centre T cells co-expressing HNK-1 antigen have little lytic activity against NK targets (K562 cells). In order to determine whether these cells regulate B cell function, they were purified from human tonsils by panning on anti-HNK-1 antibody coated Petri dishes and co-cultured with autologous and allogeneic tonsillar T and B cells in the presence of pokeweed mitogen. At the end of 7 days of culture, supernatants were assayed for immunoglobulin concentration by ELISA. A dose-dependent suppression of both IgG and IgM production was demonstrated at ratios from 1:125 to 1:16 of HNK-1+ cells to B cells, but enhancement was observed at very low ratios (less than 1:500) or ratios exceeding 1:16 in some tonsil preparations. Similar results were obtained with peripheral blood HNK-1+ cells but without enhancement in some cases at the extremes of HNK-1+ cells to B cell ratios. The suppression was not MHC-restricted. These preliminary experiments indicate that germinal centre HNK-1+ cells may be intrafollicular suppressor cells.
To investigate the mechanisms of the negative inotropic effects of contrast media, we superfused spontaneously contracting cultured chick embryo ventricular cells with Renografin-76 and iohexol (12% solutions), and hypertonic sucrose during simultaneous measurement of [Ca2+]i transients (indo-1) and motion (video-motion detector system). Exposure to contrast agents caused a significant reduction of contractility, with Renografin-76 having a much greater effect on amplitude of motion than iohexol. Renografin-76 significantly depressed [Ca2+]i transient amplitude, whereas iohexol had no effect. Addition of Ca2+ to correct for calcium binding by Renografin-76 completely reversed its depression of [Ca2+]i transients but only partially reversed the negative inotropic effects. Hypertonic sucrose caused a significant decrease in contraction amplitude, with no significant effects on [Ca2+]i transient amplitude. We conclude that the marked negative inotropic effect of Renografin-76 is caused by both calcium binding and hypertonicity. The less marked depression of contractility produced by iohexol likely is a result of hypertonicity and not caused by alteration of [Ca2+]i.
Sodium aurothiomalate (GSTM) inhibited the pokeweed mitogen induced plaque forming cell (PFC) response in a dose dependent manner. This inhibition was irreversible as preincubation for 2 h with the drug followed by washes still caused a suppression of the PFC response. Pretreatment of the different mononuclear cell populations necessary for the PFC response with GSTM for short periods (2-24 h) showed that both macrophages (M phi) and B lymphocytes were inhibited by the drug but that T cells were resistant. In the case of GSTM treated M phi the response was restored partially with exogenous interleukin-1, and completely with the addition of 20% fresh M phi. Our results show that the inhibition of polyclonal immunoglobulin secretion by human mononuclear cells in vitro is due to an effect of GSTM on both M phi and B lymphocytes. This may explain the decrease in serum immunoglobulin levels seen in patients receiving chrysotherapy.
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Monoclonal antibodies and the avidin-biotin immunoperoxidase technique were used to study the expression of major histocompatibility complex antigens and the nature of the inflammatory cell infiltrate in 10 testicular seminomas. Tumor cells did not react with anti-HLA-A,B,C, anti-HLA-DR, anti-HLA-DQ, and anti-beta 2 microglobulin antibodies to major histocompatibility antigens. All of the 10 tumors contained a slight to marked inflammatory cell infiltrate at the periphery of the tumor, in the connective tissue septa, and in the tumor lobules. The lymphocytes were predominantly T cells; B lymphocytes were rare. The tissue available for study from seven tumors showed tumor lobules separated by delicate fibrovascular septa; T lymphocytes with a cytotoxic-suppressor phenotype predominated in this area in six tumors. In the four tumors in which peripheral tissue was available for study, cells with a helper-inducer phenotype predominated at the tumor margin. Tissue from three tumors showed stromal sclerosis and a dense lymphohistiocytic infiltrate separating individual and small nests of tumor cells; T cells with a helper-inducer phenotype predominated in these cases. Aggregates of macrophages that expressed OKM-1 and Leu-M3 were present in eight of 10 tumors. These findings indicate that two types of immune reactions may be operating: a delayed-type hypersensitivity response at the periphery and a cytotoxic-suppressor effector mechanism in the tumor lobules. Furthermore, major histocompatibility complex antigens are not involved in eliciting the inflammatory response.
One idiotype family 4.6.3 derived from a human hybridoma IgML monoclonal anti-DNA antibody of normal origin is commonly expressed (approximately 85%) in the serum of patients with systemic lupus erythematosus but not in normal controls, where its level appears to fluctuate with clinical disease activity. In contrast, the IgM released by normal cultured lymphocytes in vitro expresses this idiotype family but does not bind DNA. Both idiotype 4.6.3 and anti-DNA antibodies are frequently detectable in the serum of patients with monoclonal IgM but not IgG. Therefore, it is likely that idiotype 4.6.3 reflects the expression of a common germ line immunoglobulin gene family. Some of the IgM molecules encoded by these germ line immunoglobulin genes also bind DNA.
A malignant schwannoma, apparently arising in the left ovary of a 71-year-old woman is described. The patient had no stigmata of von Recklinghausen's disease. The tumor was located in the position of the left ovary and had metastasized throughout the peritoneal cavity. The neural sheath origin of the tumor was confirmed by electron microscopic examination. The tumor is thought to have arisen from small nerves in the ovarian hilus.
Seventy patients with primary fibrositis satisfying Smythe's criteria were studied in a 9-week double-blind trial comparing 50 mg amitriptyline with placebo. Fifty-nine patients completed the trial: 27 were treated with amitriptyline, and 32 took a placebo. The patients who received amitriptyline improved significantly in their morning stiffness and pain analog scores at 5 and 9 weeks, compared with baseline scores, whereas no changes were noted in these parameters in the placebo group. Fibrocytic point tenderness did not improve significantly in either of the treatment groups. When compared with the placebo group, the amitriptyline group improved significantly with respect to sleep pattern and patient and physician global assessments. Our data indicate that amitriptyline has some therapeutic benefit in patients with primary fibrositis.
The ability of monoclonal IgM anti-DNA autoantibodies derived from normal human lymphoid cells to bind to cellular constituents of human epithelial cells (HEp-2) was examined by immunofluorescence. Hybridoma supernatants from 10 different clones were studied. Four of them gave a strong fibrillar cytoplasmic staining that resembled cytoskeletal staining, 1 showed strong nuclear staining only, 3 showed weak nucleolar staining only, and 2 showed no staining. The hybridoma supernatants that reacted with HEp-2 cytoskeleton were either polyspecific for various nucleic acid antigens, such as single-stranded DNA, DNA, poly(dA:dT), poly(dG).poly(dC), RNA, and cardiolipin, or were restricted to cardiolipin. Cytoskeletal staining identical to the hybridoma supernatant staining was also seen with mouse monoclonal anti-vimentin antibody B11.5.1. Inhibition of the cytoskeletal staining was accomplished in 3 of the 4 hybridoma supernatants by preabsorption of these hybridoma supernatants with cardiolipin and/or single-stranded DNA, or by preincubation of the HEp-2 cells with the mouse monoclonal anti-vimentin antibody.
The effect of pregnancy on patients with CCA of the vagina and cervix was evaluated based upon a review of 503 cases. Eighty-five had been pregnant (24 at diagnosis), 408 had never been pregnant, and the pregnancy history was unavailable in 10 cases. All of the 24 patients pregnant at diagnosis were over 16 years of age; 14 were in the first trimester, 6 in the second, and 4 in the third trimester. By FIGO criteria, 15 were stage I, 7 stage II, and 2 were stage III. The 24 pregnant and 408 never pregnant (age corrected) cases were compared with regard to maternal hormone history, symptoms, stage, location, predominant histologic or cell type, greatest tumor diameter, surface area, depth of invasion, grade, and number of mitoses. No significant differences were detected. Twelve of the 24 pregnant patients had radical hysterectomy with or without irradiation (9 stage I, 3 stage II); of the 7 treated by local therapy (5 stage I, 2 stage II), 3 required additional therapy due to persistent disease; 4 had radiotherapy alone (1 stage I, 2 stage II, and 1 stage III); one had teletherapy followed by exenteration (stage III). Six of the 24 died 2 to 12 years after diagnosis (1 stage I, 3 stage II, 2 stage III). Eighteen are alive at 1 to 17 years. The overall 5 and 10 year actuarial survival rates (age adjusted) for the group pregnant at diagnosis (86 and 68%) do not differ significantly from the never pregnant group. Pregnancy does not seem to adversely affect the outcome of CCA. Guidelines are presented to treat pregnant patients with CCA.
Three cases of giant cell arteritis involving the female genital tract of postmenopausal women are reported. The patients were 80, 64, and 57 years of age and presented with fatigue and anemia, fatigue and an abdominal mass, and fever and weight loss, respectively. Two of the patients had palpable pelvic masses; one had an ovarian mass visible on ultrasound examination. All three patients were anemic, and the erythrocyte sedimentation rate was elevated in the two women in whom it was tested. Exploratory laparotomy revealed ovarian tumors in two patients; one had a mucinous cystadenoma, and one had bilateral ovarian fibromas. The third patient had a cyst of the rete ovarii. Extensive giant cell arteritis of the small to medium-sized arteries was found unexpectedly in the ovaries and fallopian tubes of two patients who had prior hysterectomies and in the ovaries, fallopian tubes, and uterus of one patient. One patient was treated postoperatively with prednisone with improvement of symptoms and a decrease in the erythrocyte sedimentation rate. Of the two patients who received no therapy, one was found to have a thoracic aortic aneurysm 5 years postoperatively, and the other was alive without symptoms 17 years after the operation. Giant cell arteritis of the female genital tract is a rare finding in elderly women and may occur as an isolated finding or as part of generalized giant cell arteritis.
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The criteria for the diagnosis of benign and borderline clear cell adenofibromas and their biologic behavior were investigated by examination of the clinical and pathologic features of 18 tumors in these categories. Three tumors that showed no significant epithelial atypicality were classified as benign. Twelve tumors that contained glands or small solid nests composed of epithelial cells with nuclear characteristics of low-grade malignancy without invasion of the stromal component of the tumor were designated as borderline. Three predominantly borderline tumors with focal microinvasion of the stromal component were also studied. The 17 patients had nonspecific complaints. Sixteen of the tumors were unilateral without surface involvement; one patient had bilateral borderline tumors. Most of the women were treated by hysterectomy and bilateral salpingo-oophorectomy. Follow-up information was available for 16 of the 17 patients. No recurrences or deaths from tumor occurred in 14 patients (2 benign, 10 borderline, 2 microinvasive). One patient with a borderline adenofibroma had questionable lung metastasis 4 years after presentation, and another patient who had a microinvasive tumor had a pelvic recurrence 3.3 years postoperatively.
The spontaneous in vitro anti-DNA antibody response generated by preautoimmune and many normal mouse spleen cells was suppressed by the addition of syngeneic thymocytes or splenic T cells. Suppressive activity was found in normal mice (DBA/2J) and to an equivalent degree in the autoimmune (New Zealand Black X New Zealand White)F1 (B/W) strain. The suppressor cells were cortisone-resistant, radiosensitive and carried Lyt 1 and Lyt 2 markers. Nonspecific suppression was not involved since the primary and primed in vitro anti-sheep erythrocyte (anti-SRBC) responses were unaffected. Both spontaneous and lipopolysaccharide-stimulated anti-DNA antibody responses could be suppressed. There was no difference in the suppressive activity of cells from young or old, normal or autoimmune mice. These T cells may therefore play a role in preventing the anti-DNA antibody response in normal and young B/W mice, but evidently fail to influence the development of in vivo anti-DNA autoimmune responses in the old B/W mice.
The state of development of Distributed Database Systems (DDB) is briefly surveyed and a basic taxonomy of the products, prototypes and architectures presented. The applicability of the approach to applications arising in primary medical care networks is assessed by looking in some detail at three particular offerings in this field. Some insights into and implications for the future direction of DDB research and development are gained from this.
The significance of varying degrees of epithelial atypicality was investigated in 27 endometrioid adenofibromas and cystadenofibromas of the ovary. The tumors were classified as atypical or borderline on the basis of the degree of atypicality of the epithelial element. All tumors were confined to the ovary at the initial operation and most of them were treated by a hysterectomy and bilateral salpingo-oophorectomy. Seven tumors with mild to severe cytologic and architectural atypicality similar to that encountered in atypical endometrial hyperplasia were classified as atypical adenofibromas. No recurrences or deaths from tumor occurred in patients with this type of tumor during 1-18.5 years of follow-up. Twenty tumors that contained closely packed glands or epithelial islands with a cribriform pattern composed of cells with low-grade malignant nuclear characteristics embedded in an abundant fibromatous stroma without evidence of invasion were classified as borderline. Nineteen patients with tumors of this type had no evidence of disease 1-13 years after initial therapy. One of these tumors was discovered at autopsy. These data, although based on a relatively small series of cases, suggest that atypical endometrioid adenofibromas and those of borderline malignancy have an excellent prognosis.