Squamous cell carcinoma antigen: clinical utility in squamous cell carcinoma of the uterine cervix

This study further defines the clinical utility of squamous cell carcinoma antigen (SCC-Ag) in initial squamous carcinoma of the cervix, response to treatment, and in the detection of recurrence. Serum specimens were drawn and analyzed from patients with squamous cell carcinoma. Charts were reviewed on 272 patients with 1053 samples evaluated. Treatment of patients prior to the availability of the assay and patients lost to follow-up resulted in lower total numbers of initial and recurrent values. Data were analyzed to detect trends during and after treatment. All values at or above the lowest detectable level of antigen were included; that is, 1.5 ng/ml and above. A SCC-Ag value > or = 2.0 ng/ml drawn at any time during the disease process has a 96.3% positive predictive value, while a value < 2.0 ng/ml is 97.2% specific for absence of disease. Fifty-three percent of 103 patients had elevated SCC-Ag levels prior to treatment, with the proportion increasing accordingly with advancing stage at diagnosis. In 70 patients with recurrence, 81% had elevated values. Squamous cell carcinoma antigen predicted recurrence an average of 6.9 months prior to detection of clinically evident disease. Patients with initially negative SCC-Ag levels may demonstrate elevated values with tumor recurrence. This marker accurately reflects the response to treatment in patients who have elevated levels prior to treatment. Squamous cell carcinoma antigen is a useful tumor marker in the management of patients with squamous cell carcinoma of the uterine cervix.

Staffing and funding of consultation-liaison psychiatry services in Australia and New Zealand

The aim of the study was to establish the current and desired levels of staffing and funding of the 52 consultation-liaison (C-L) psychiatry training units in Australian and New Zealand general hospitals. Administration of a questionnaire and follow-up verification provided data on referral rates, existing and preferred staffing levels, and staff workloads. The referral rates and staffing levels in most cases fall below those quoted for Europe and the USA, and those considered optimal by the respondents. This, together with the large variation in referral rates and workload, has implications for the type of clinical activity conducted and quality of the training experience in different units.

Psychiatric issues in the "loin pain and haematuria syndrome"

The Loin Pain and Haematuria Syndrome is a relatively new diagnosis applied to the problem of persistent loin pain, often with haematuria, in the absence of identifiable explanatory organic pathology. Case reports have suggested a range of salient psychopathological features associated with the complaints of pain and haematuria, although the psychological factors have been largely neglected in understanding the aetiology or in approaches to management. The roles of illness behaviour, patterns of somatisation, and psychiatric disorder associated with chronic pain syndromes, need to be addressed, as do the patterns of medical and surgical response to these patients. The use of the term "syndrome" to describe these symptoms implies a degree of uniformity in clinical features and outcome that has not yet been substantiated. New surgical techniques have been developed such as renal denervation and renal auto-transplantation to treat the pain, with limited success. A review of this condition illustrates the frequent failure of medicine to apply multi-factorial biopsychosocial models to understanding the aetiology and management of unexplained physical symptoms. It also illustrates the failure of our current nosology and understanding of somatoform disorders to achieve application outside psychiatry.

The matter of informed consent. A case history

This case history outlines some of the difficulties in obtaining informed consent from a patient with a psychotic illness. It also makes reference to an array of other issues, for example, communication between professionals, the value of home visits, the need to be aware of medication side effects and the simple explanation for an apparently baffling clinical presentation.

Safer staining method for acid fast bacilli

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Illness behaviour of patients with chronic fatigue syndrome

The study examines the illness behaviour of patients with Chronic Fatigue Syndrome (CFS). The Illness Behaviour Questionnaire (IBQ), the twenty-eight version of the General Health Questionnaire (GHQ-28), and the Beck Depression Inventory (BDI) were administered to forty patients with a diagnosis of CFS. The results revealed that CFS patients in comparison with general practice patients, scored significantly higher on the IBQ sub-scales of General Hypochonriasis, t(188) = 5.2, p < 0.001 and Disease Conviction, t(188) = 13.28, p < 0.001 but lower on the Psychological/Somatic sub-scale, t(188) = -5.88, p < 0.001. The CFS and psychiatric patients did not differ significantly on the general hypochondriasis sub-scale. Results of the GHQ-28 revealed 66.7% of the CFS patients scored above the cut-off for psychiatric morbidity. In comparison to a previous study of CFS patients [1], the current findings indicate a significantly higher score on general hypochondriasis. The implications of these findings are discussed.

Pneumoperitoneum due to PCI in a patient with a strangulated femoral hernia

Although pneumatosis cystoides intestinalis (PCI) is a well-recognised condition, an individual surgeon is unlikely to encounter it often. The collected experience of two surgical units in Glasgow teaching hospitals over a 15-year period consisted of five patients. Surgical and radiological trainees may therefore have little or no exposure to the diagnostic difficulties this condition can cause. We report an illustrative case.

Optical implementation of a second-order translation-invariant network algorithm

Higher-order networks, particularly second-order translation-invariant networks, are introduced, and their suitability for optical implementation is outlined. The algorithm is implemented with a conventional liquid-crystal display, permitting on-line learning and updating of weights. The basic operation of the optical system is demonstrated, and the ability of the system to adapt to system nonuniformities is illustrated. The implementation with an integrated optoelectronic array of asymmetric Fabry-Perot modulators containing a GaAs/AlGaAs multiple-quantum-well active region is described. The principles of operation and operating characteristics of the device array are outlined. The use of the array in an optical system to calculate the autocorrelation matrix necessary for a second-order network is demonstrated.

Further evidence that scopolamine can improve verbal fluency

Scopolamine usually is found to impair various aspects of human cognitive performance. Recently, however, a significant (though modest) improvement in verbal fluency has been reported following scopolamine hydrobromide (0.6 and 1.2 mg p.o.). This study replicated that effect, finding significantly better FAS letter fluency in contrast to poorer performance on other neuropsychological measures following sub cutaneous injection of 0.4 mg scopolamine. Data are discussed in terms of a functional state model of drug action.

The "real world" of hospital nursing practice as perceived by nursing undergraduates

The purpose of this study was to examine the expectations of senior nursing undergraduates in the "real world" of hospital nursing practice, with particular regard to the ethical dimensions of their role. The method was qualitative; specifically, a grounded theory approach was used. The sample consisted of 23 senior baccalaureate nursing students, from a possible population of 120, who were in their final clinical rotation before graduation. Informants were volunteers who gave informed consent, having been briefed on the purposes of the study and how their confidentiality would be protected. Data were collected through audiotaped interviews and clinical logs and analyzed through the constant comparative method. The study concluded that (1) senior nursing students were not naive about the reality of practice; (2) most perceived themselves as fairly powerless; (3) they voiced a commitment to the ethical principle of respect for the client as evidenced by listening, providing information, accepting values, and encouraging a climate for self-determination; (4) they experienced guilt when they did not "say something"; and (5) they expressed disappointment that nurses did not "stand up" for patients.

Developmental expression of major myelin protein genes in the CNS of X-linked hypomyelinating mutant rumpshaker

Rumpshaker (rsh) is an X-linked mutation causing hypomyelination of the CNS of mice and has recently been identified as an allele of jimpy (jp). The mutation (known as jprsh) differs in several respects from other X-linked myelin mutants, including jp, in that mice have normal longevity, oligodendrocyte numbers are not decreased, and cell death is not a feature. Myelin sheaths are deficient in immunostainable PLP protein. The present study examines the developmental expression of the major myelin protein genes and translatability of PLP and MBP mRNA. Differences between the spinal cord and brain of mutants are evident in that mRNA levels are more markedly decreased in the brain. Protein levels are severely reduced in both locations and to a proportionately greater extent than the mRNA, particularly in the spinal cord where PLP RNA and protein are approximately 80% and 10-20%, respectively, of age-matched wild type mice. DM-20 protein, the other major product of the PLP gene, is disproportionately expressed in rumpshaker as is a 10 kDa proteolipid. In vitro translation studies indicate a marked decrease in PLP translation products from mutant RNA. There is no deficiency in the number of PLP mRNA-expressing oligodendrocytes although the abundance per cell is reduced. The data suggest that the phenotypic effects of the mutation may be associated with reduced translation of major myelin proteins, in particular PLP and its incorporation into compact myelin. However, the mutation is compatible with survival of oligodendrocytes and their differentiation to the stage of expressing PLP/DM-20 mRNA.

The Professional Self-Concepts of Nursing Undergraduates and Their Perceptions of Influential Forces

This article explores the professional self-concepts of senior nursing undergraduates and their perceptions of the most significant forces that influenced the process. The method was qualitative; a grounded theory approach was used. The sample included 23 senior baccalaureate nursing students in their final clinical rotation prior to graduation. Audiotaped interviews were analyzed through the constant comparative method. Informants overwhelmingly perceived themselves as caring. They valued professional competence and many identified a lack of confidence in their skills. Caring qualities, caring role models, and qualities of the role models are listed.

Professional ethics as perceived by American nursing undergraduates

The purpose of the study was to explore the perceptions of American nursing undergraduates about professional ethics. The method was qualitative; specifically, a grounded theory approach was used. The sample comprised 23 senior baccalaureate nursing students, from a possible population of 120, who were in their final clinical rotation prior to graduation. Informants were volunteers who gave informed consent having been briefed on the purposes of the study and how their confidentiality would be protected. Data were collected through audio-taped interviews and clinical logs. Analysis was conducted through the constant comparative method. Findings revealed two concepts central to their view of good nursing. These were: (a) respect, and (b) caring. Respect was described as respect for patients and families, respect for self, colleagues and the profession. Caring was associated with showing 'concern and love', providing psychological support, getting involved, being 'cheerful and friendly' and 'taking the time' to do a good job. They did not evidence an ambiguous professional role. They espoused values consistent with the professional code of ethics. They perceived that respect for others was basic to good nursing. They believed that good nurses cared about their patients and how nursing was done. They appeared to link professionalism with good nursing.

Relationships between mental adjustment to HIV diagnosis, psychological morbidity and sexual behaviour

This paper examines patterns of psychological adjustment in a small sample of asymptomatic HIV antibody positive men. Comparison is made with data available on male cancer patients. HIV positive men reported greater degrees of anxious preoccupation and hopelessness, and lower levels of the more adaptive 'fighting spirit' response. In HIV-infected men, depression correlated positively with frequency of high risk sexual practices.

The professional values of English nursing undergraduates

The purpose of the study was to examine and describe what English nursing undergraduates internalize as professional values. The method was qualitative; specifically, a grounded theory approach was used. The sample comprised 12 senior baccalaureate nursing students from two educational institutions in the north of England. Informants were volunteers who gave informed consent having been briefed on the purposes of the study and how their confidentiality would be protected. Data were collected through audio-taped interviews and the constant comparative method was used to analyse data. The findings revealed that informants perceived two concepts as central to their professional values. These were respect for patients and 'caring about the little things'. They valued the rights of patients to be treated with respect, to know what was happening to them and to have a say in what happened to them. They described the 'little things' as 'an approach with patients that gets through to them'; 'getting out the mirror so they can see themselves'; 'fixing their water so they can reach it'; worrying about someone's dentures or the cat they left at home. They expected that their values would be in conflict with common hospital practice. They valued 'fitting in' and 'going along' but retained their own ideas and values until such time as these could be implemented. They perceived themselves as powerless to create change as new graduates. They believed the overwhelming power resided in the hospital system and the ward sister/charge nurse. They were not inclined toward a career in hospital nursing.

Effect of otitis media on infrared tympanic thermometry

This study was designed to determine if temperature readings using a new tympanic thermometer are affected by otitis media. These readings were also compared to a rectal or oral temperature. Eighty-four children with unilateral suppurative or non-suppurative otitis media diagnosed clinically by their pediatricians were enrolled in the study. Temperatures were measured in both ears using the Thermoscan PRO-1 Instant Thermometer and rectally or orally by a glass or electronic predictive thermometer. For 67 children with unilateral suppurative otitis media the mean temperature in infected ears was 0.38 degrees Fahrenheit higher than in uninfected ears (p = .005). Neither temperatures measured in affected nor those from unaffected ears differed significantly from oral or rectal control readings. For 17 children with unilateral non-suppurative otitis media there was no statistically significant difference between temperatures in affected and unaffected ears or between the temperatures in either ear and the oral or rectal control. Our data show that temperatures taken in ears with suppurative otitis media are slightly higher than those in normal ears. This difference is of minimal clinical significance and does not affect the accuracy when compared to oral or rectal control readings.

Cost effectiveness of tympanic thermometry in the pediatric office setting

This study was designed to see if tympanic thermometry might be more cost effective than cheaper more traditional methods of thermometry when office staff time saved is taken into account. There were 224 patients enrolled from three private pediatric practices. Patients were alternately assigned to have their temperature taken with either a tympanic thermometer or with a rectal or oral thermometer depending on the patient's age. For each child enrolled in the study a nurse was asked to time the temperature taking process. Items included in the cost analysis: a) thermometer costs; b) disposable supply costs; c) personnel costs; d) equipment service costs. The mean duration of temperature taking was 35.2 seconds using tympanic thermometers, 73.4 seconds using electronic predictive thermometers, and 247.2 seconds using glass thermometers. In practices taking an average of 10 temperatures per day, tympanic thermometry saved $2,316/year when compared to glass thermometers and $442/year when compared to electronic predictive thermometers. The data presented in this study show that when nursing time is taken into account, tympanic thermometry is less expensive to perform than traditional methods of thermometry despite the initial higher cost of the thermometer.

Responses of children, parents, and nurses to tympanic thermometry in the pediatric office

This study was designed to assess children's behavioral responses to tympanic thermometry. In addition, parents' and nurses' impressions of this new technology were evaluated. 224 patients were enrolled from three private pediatric practices. Patients were alternately assigned to have their temperature taken with either a tympanic thermometer or with a rectal or oral thermometer. Parents and nurses were then asked to fill out a short questionnaire to describe their observations of the child's behavior during temperature taking and to describe their own feelings about the temperature taking method used. Parents were also asked to assess their usual method of temperature taking at home and their child's usual behavioral response. Tympanic thermometry was rated higher by both parents and nurses for speed, ease, cleanliness, and safety. Parents and nurses were more confident in the accuracy of traditional temperature taking methods. Children whose temperatures were taken rectally were more likely to be observed by both parents (p = .02) and nurses (p = .01) to have a negative behavioral reaction to the procedure than children whose temperatures were taken by tympanic thermometry. There was no difference observed between the behavioral responses of children who had temperatures taken orally and those who had tympanic thermometry.

Emily: a study of grief and bereavement

The author's purpose in presenting this article is to describe and interpret the phenomena that contributed to a state of extended bereavement in an 83-year-old window. The problem concerned a newly admitted nursing home resident who appeared to be experiencing profound grief at the loss of a husband who had died 12 years earlier. The method was qualitative, specifically, ethnographic. This case study focuses on the life history of one individual as she perceived it. The question posed for the study was what are the factors contributing to a grief reaction in an elderly widow 12 years after her husband's death? To answer this question a series of interviews were conducted with the informant. The data were then analyzed for meaning in light of current theory in grief and bereavement. The findings, presented in the informant's words, highlight the importance of suddenness, multiplicity of losses, relationship with the deceased spouse, and personal characteristics of the bereaved.

The use of biomarkers in the prediction of survival in patients with pulmonary carcinoma

Data on ten variables and 16 biomarkers were obtained on 119 patients with newly diagnosed pulmonary cancer. The prognostic value of 16 biomarkers (alpha-1-antitrypsin [AAT], adrenocorticotropic hormone [ACTH], alpha-fetoprotein [AFP], carcinoembryonic antigen [CEA], human chorionic gonadotropin [HCG], immune complexes, immunoglobulins, N-terminal peptide of proopiomelanocortin [NTERM], and tumor-associated antibody [TAA]) was tested by adding these to the model of age, gender, stage, morphology, Feinstein's classification of symptoms, Karnofsky scale, leukocyte count, recent weight loss, and liver enzymes. Using Cox's regression method and a forward stepwise procedure, seven biomarkers (ACTH, AAT, AFP, calcitonin, HCG, TAA, and prolactin) entered the model. Elevated levels of cortisol and TAA were associated with longer survival. The selection of biomarkers by stepwise regression needs to be interpreted with caution, especially since the Z scores were found to be dependent on the particular variables included in the model. Furthermore, when dichotomized on maximum of the normal laboratory values, HCG and AFP were infrequently (2%) elevated. The lack of correlation among the biomarkers supports the hypothesis of random derepression of the genome of cancer cells. Further studies in improved modeling and the formulation of a biomarker index could enhance our understanding of the biology of cancer.

Oxygen radicals and antioxidant enzymes alter pulmonary vascular reactivity in the rat lung

It has been postulated that changes in the availability of partially reduced O2 species, such as O2 radicals, could serve as a link between PO2 in the alveolus and pulmonary vascular tone (Herz 11: 127-141, 1986). To assess this hypothesis, the hemodynamic effects of acute changes in the balance between the production of O2 radicals and availability of antioxidant enzymes were studied in the isolated perfused rat lung. Intravascular generation of O2 radicals, by administration of xanthine-xanthine oxidase, decreased the pulmonary vascular pressor response to alveolar hypoxia (-55 +/- 5%) and angiotensin II (-58 +/- 10%, P less than 0.01 for each) in isolated perfused rat lungs without increasing the lung wet-to-dry weight ratio. Decreases in pulmonary vascular reactivity were inhibited by pretreatment of the lung with desferrioxamine or a mixture of catalase and superoxide dismutase. Catalase and superoxide dismutase preserved the hypoxic pressor response whether given in liposomes or in dissolved form. Superoxide dismutase administered free in solution, or combined with catalase in liposomes, increased the normoxic pulmonary arterial pressure and enhanced vascular reactivity to angiotensin II and hypoxia. Lungs treated with antioxidant enzymes in liposomes had 50% higher lung catalase levels than control lungs (P less than 0.05). These findings demonstrate that exogenous partially reduced O2 species can decrease pulmonary vascular reactivity and suggest that endogenous radicals, superoxide radical in particular, might be important in modulating pulmonary vascular tone.

Prostaglandins as reducing agents: a model of adenylate cyclase activation?

It has been suggested that adenylate cyclase activation involves reduction of a disulfide linkage. Prostaglandin E1 (PGE1), prostaglandin E2 (PGE2), prostaglandin I2 (PGI2) and prostaglandin F2 alpha (PGF2 alpha) were tested for their ability to act as reducing agents with either cytochrome c, or the disulfide 5,5'-dithiobis(2-nitrobenzoic acid) (DTNB), the latter with a catalytic amount of ferric chloride. PGE1, PGE2, and PGI2 significantly reduced cytochrome c while PGF2 alpha did not. PGE1, PGE2 and PGI2 reduced DTNB while PGF2 alpha did not. The results are consistent with the postulate that prostaglandins which are effective in activating adenylate cyclase can act as reducing agents and might be involved in reductive activation of adenylate cyclase.

Phosphorylation of tyrosine enhances its electron transfer capability: a model of redox modulation as oncogene expression?

The influence of tyrosine and o-phosphotyrosine on the transfer of electrons to nitrobluetetrazolium (NBT) was studied. Tyrosine phosphate was found to strongly promote the transfer of electrons from ferrous iron to NBT, while tyrosine was inhibitory. The enhancement of NBT reduction by tyrosine phosphate was blocked by superoxide dismutase (SOD). The results suggest a role for phosphorylated tyrosine residues to promote intracellular redox reactions. We suggest that the role of tyrosine protein kinases in cell proliferation and transformation may be to regulate electron transport in as yet undefined cellular systems. Consistent with a unique role for phosphotyrosine, the other commonly occurring phosphoamino acids, o-phosphoserine and o-phosphothreonine were not effective electron transfer agents.

Preliminary studies on a more effective phototoxic agent than hematoporphyrin

Phototoxicity of benzoporphyrin derivative (BPD) has been tested in vitro and compared with that of hematoporphyrin (HP). After 1-hour activation with visible light, BPD was 10 times more cytotoxic than HP toward human adherent cell lines: A549 lung cancer, Calu-1 lung carcinoma, and CCD-19Lu normal lung, killing 100% of cells at the concentration of 70 ng/ml. Under the same conditions, BPD was 10-70 times more cytotoxic than HP toward nonadherent cells and cell lines. Tested were human leukemia cell lines HL60, K562, and KG1, normal human lymphocytes, and mouse mastocytoma cell line P815. The concentrations required to kill 100% of cells varied between 10 and 500 ng BPD/ml and between 0.2 and 10 micrograms HP/ml. The difference between the nonadherent cell lines in respect to their sensitivity to phototoxicity of both BPD and HP seemed to be related to the cell sizes, with the smallest cells being the most vulnerable. The most attractive characteristic of BPD in addition to its powerful phototoxicity is its maximum absorption around 700 nm, which is in the range of wavelengths penetrating tissues the best. This characteristic alone could make BPD a drug of choice in cancer photodynamic therapy when the safety of its use is ensured. Preliminary tests in vivo have shown that DBA/2J mice can tolerate a single ip injection of 20-60 micrograms BPD as well as the same dose of HP. The biodistribution and toxicity studies of BPD are under way in our laboratory.

Safety education in a pediatric primary care setting

Parents of 171 children coming to the Yale-New Haven Hospital Primary Care Center for their 6-month checkup were randomized into an intervention group (n = 85) and a control group (n = 86). Parents in the intervention group received a three-part individualized course in child safety that required active parental participation. Parts 1, 2, and 3 were given at the 6-month, 9-month, and 12-month well-child visits, respectively. Parents in the control group received routine safety education as provided at well-child visits. The educational phase of the study was completed by 129 families, 65 in the intervention group and 64 in the control group. Safety knowledge, number of hazards in the home, and reported accidents were assessed by a "blinded" community health worker approximately 1 month after the 12-month well-child visit. A total of 109 home visits were made, 55 for the intervention group and 54 for the control group. Parental safety knowledge was assessed based upon pictorial hazard recognition. Of 13 possible hazards, the mean number of hazards recognized by the intervention group parents was 9.4 (n = 55) v 8.4 (n = 50) by the control group parents (t = 2.1, P less than .05, two-tailed). A hazard score was determined for each family based on nine possible hazards observed at the home visit. The mean hazard score for the intervention group was 2.4 (n = 55 v 3.0 (n = 54) for the control group (t = 2.4, P less than .02, two-tailed). Parentally reported accidents and accidents reported in hospital records were similar for both groups. Results of this study suggest that age-appropriate safety education that is repetitive and individualized and that requires active parental participation results in an increase in parental knowledge and an improvement in certain safety practices.

Biologically active precursor for transforming growth factor type alpha, released by retrovirally transformed cells

Retrovirus-transformed rat cells that actively express transforming growth factor type alpha (TGF-alpha) release into the medium a soluble protein of 17-19 kDa that has been identified as a precursor for TGF-alpha. The identification of this protein as a TGF-alpha precursor is based on its recognition by specific antibodies and by the ability of elastase to convert this protein into a 6-kDa polypeptide with the properties of mature TGF-alpha. This TGF-alpha precursor binds to epidermal growth factor/TGF-alpha receptors and activates the receptor-associated tyrosine kinase activity in intact cells. The biological potency of this precursor is not markedly increased by conversion into mature TGF-alpha in vitro. These studies demonstrate the ability of transformed cells to release a TGF-alpha precursor capable of strong mitogenic action in vivo.

Internalization of transforming growth factor-beta and its receptor in BALB/c 3T3 fibroblasts

The fate of 125I-labeled transforming growth factor-beta (125I-TGF beta) after binding to its cells surface receptor has been investigated in BALB/c 3T3 mouse fibroblasts. Binding of 125I-TGF beta to cellular receptors at 4 degrees C is pH-sensitive, being markedly decreased at pH less than 6. Most (approximately 90%) of the 125I-TGF beta bound to cells at 4 degrees C can be removed by a brief treatment with acidic medium but is converted into an acid-resistant state rapidly after shifting the cells to 37 degrees C. Cell-bound 125I-TGF beta is degraded at 37 degrees C and the degradation products are released into the medium. The lysosomotropic bases chloroquine, methylamine, and ammonium and the carboxylic ionophore monensin inhibit the degradation and release of 125I-TGF beta from the cells. Cells allowed to accumulate 125I-TGF beta intracellularly by the action of chloroquine or monensin were treated with the bifunctional agent disuccinimidyl suberate in the presence of detergent Triton X-100; this treatment caused the cross-linking of internalized 125I-TGF beta with the 280-kilodalton TGF beta receptor component. Under conditions in which sustained binding and degradation of saturating 125I-TGF beta concentrations occurs, there is no marked decrease in the binding capacity of the cells even when protein synthesis is blocked with cycloheximide. These results indicate that after TGF beta binding the TGF beta:receptor complex becomes rapidly internalized and that TGF beta is directed towards lysosomes where it is degraded and released. However, the cell surface is replenished with TGF beta receptors recycled after internalization or supplied by a large intracellular pool.

Allopurinol can act as an electron transfer agent. Is this relevant during reperfusion injury?

The xanthine oxidase inhibitor allopurinol markedly enhances myocardial function and decreases ventricular irritability during myocardial reperfusion. In the present report, we have evaluated the molecular mechanism of allopurinol action. First, allopurinol was shown to be a weak radical scavenger. Second, allopurinol was found to act as an electron transfer agent from ferrous iron to ferric cytochrome c. The results suggest that the beneficial effect of allopurinol might partially result from its facilitated electron transport during reperfusion when the lipid components of the chain can be expected to be disordered.

Stimulation by insulin-like growth factors is required for cellular transformation by type beta transforming growth factor

Medium conditioned by BRL-3A cells, a known source of insulin-like growth factor II (IGF-II), induced phenotypic transformation (anchorage-independent proliferation) of mouse BALB/c 3T3 fibroblasts but not rat NRK-49F fibroblasts, in the presence of 10% calf serum. A specific radioreceptor assay and a bioassay indicated that BRL-3A conditioned medium contained 0.5-1 ng/ml of type beta transforming growth factor (beta TGF). Purified IGF-II and beta TGF acting together reconstituted the transforming activity of BRL-3A conditioned medium on BALB/c 3T3 cells. Insulin was 5-10% as potent as IGF-II in supporting the transforming action of beta TGF on BALB/c 3T3 cells. NRK-49F cells were phenotypically transformed by beta TGF in the presence of EGF and 10% calf serum as the sole source of IGFs. However, transformation of NRK-49F cells under these conditions was inhibited by addition of purified IGF-binding protein. Addition of an excess of IGF-II prevented the inhibitory action of IGF-binding protein. The different sensitivity of the two cell lines to IGFs was correlated with lower levels of type I IGF receptor and higher levels of type II IGF receptor in NRK-49F cells as compared with BALB/c 3T3 cells. The results suggest that cellular stimulation by IGFs is a prerequisite for transformation of rodent fibroblasts by beta TGF. We propose that transformation of fibroblasts by beta TGF requires concomitant stimulation by the set of growth factors that support normal cell proliferation.

Clinical experience with intravenous misonidazole for carcinoma of the esophagus: results in attempting radiosensitization of each fraction of exposure

By using intravenous misonidazole, a hypoxic cell radiosensitizer, we attempted to test the hypothesis of hypoxia as the basis of the relatively poor results seen with radiation therapy in the treatment of carcinoma of the thoracic esophagus. As the peripheral neuropathy of misonidazole was well recognized, we felt that an adequate dose of misonidazole could be given approximately ten times before peripheral neuropathy would necessitate its discontinuation. Because of a desire to maximize any possible effects of radiosensitization, it was decided to administer misonidazole with each fraction of radiation, attempting to deliver curative radiation therapy with only ten fractions of radiation. We thus devised a scheme of radiation consisting of 400 rad twice a week for 5 weeks, a total of 4000 rad. Originally the attempt was made to utilize preoperative radiation therapy and assess the histologic specimens for efficacy. However, major pulmonary toxicity caused revision of that plan. Twenty six patients were treated with radiotherapy alone without surgery, 12 of the patients being randomized to receive intravenous misonidazole with 10 fractions of 400 rad each. In terms of partial response, complete response, local control, and long-term survival, there was no suggestion of any benefit of intravenous misonidazole in these patients. As a consequence, although the number of study patients was small, the investigation was discontinued. Possible explanations for the failure to demonstrate any benefit of misonidazole are discussed.

Fine structure and invasive behaviour of the early developmental stages of Theileria annulata in vitro

The interaction, in vitro, between bovine peripheral blood lymphocytes and sporozoites of Theileria annulata (Ankara) was studied by light and electron microscopy. Beginning five minutes following incubation, samples were taken for Giemsa-stained smears and glutaraldehyde-fixed pellets, for light and electron microscopy, respectively. Sporozoites of T. annulata measure an average of 0.9 microns long, 0.8 microns broad and possess a limiting unit membrane, the pellicle; a round-to-ovoid, eccentrically situated, non-chromocentric nucleus; double-membraned, tubular, acristate mitochondria; varying numbers of anisocytic, densely osmiophilic and pleomorphic organelles, the rhoptries which together with the polar ring form the apical complex; and numerous, loosely scattered, electron-dense ribosomal particles. As early as 5 min of incubation, sporozoites had made contact with, and penetrated, lymphocytes. Sporozoites consistently attached to the lymphocyte plasmalemma by their basal end, possibly at specific receptor sites. Apparently only a proportion of lymphocytes (up to 40% and more commonly 10-20%) were susceptible. Two subpopulations of the susceptible lymphocytes were observed; one which appeared to have receptor sites localized on one pole of the plasmalemma and the other subpopulation in which the receptor sites were distributed evenly around the plasmalemmal surface. Within individual susceptible lymphocytes, the number of interiorized sporozoites increased from 1 to 3 at 5-10 min to as many as 15 or more parasites at around 60 min of incubation. Theileria annulata sporozoites were interiorized by the invagination of the host cell plasmalemma which remained intact throughout the process but later fragmented. Within 30 min of interiorization, each sporozoite underwent dedifferentiation by the loss of its rhoptries and transformed into a trophozoite. Around 24 h, the trophozoite, a uninucleate, motile and feeding stage of the parasite, developed into a schizont by an acentric, closed mitosis.

Moulting Hormones. LIII. the Synthesis and Biological Activity of Some Ecdysone Analogues

A number of ecdysone analogues were prepared to study the effect of structural changes on biological activity. It was found that analogues with the 5α-configuration or a 3,5-cyclo structure were inactive, that a 3β-hydroxy group enhances activity but is not essential for activity, and that 3β-substituents decrease activity as follows: OMe (60%), OAc (25%) and OEt (10%). The keto diol (3), keto alcohol (9) and amide (36) were found to be highly toxic to mosquito larvae.

Characterization of immunologically active peptides from the cell wall of T. mentagrophytes

A low molecular weight fraction from chitinase digested cell walls of T. mentagrophytes containing both polysaccharide and peptide moieties was found to have immunological reactivity at both the cellular and humoral level. This fraction (UM2(a)) was further degraded by treatment with either a combination of pronase and carboxypeptidase A or with trypsin. Peptides were separated from the carbohydrate-rich fraction by ultrafiltration. The carbohydrate-rich fraction retained the ability to induce both immediate and delayed skin reactions in sensitized guinea pigs and to stimulate the proliferation of sensitized lymphocytes in vitro. The peptide moieties retained reactivity in that they caused delayed reactions and lymphocyte proliferation but were unable to induce immediate or Arthus reactions in sensitized animals. Tryptic peptides from UM2(a) were purified by ion exchange chromatography. A high proportion of these peptides demonstrated immunological activity at both the cellular and humoral level since they were capable of inducing delayed reactions and/or lymphocyte transformation, as well as being capable of blocking the complement fixation reaction between UM2(a) and specific antiserum.

Isolation and partial characterization of immunologically reactive fractions from chitinase digested cell wall of Trichophyton mentagrophytes

Cell wall preparations of Trichophyton mentagrophytes were digested with chitinase following which various fractions were isolated by ultrafiltration and Sephadex gel filtration. All fractions isolated contained both polysaccharide and peptide material. A correlation was seen between those fractions capable of eliciting immediate and delayed skin reactions in sensitized guinea pigs and those capable of stimulating the in vitro proliferation of lymphocytes taken from sensitized guinea pigs. These immunologically active fractions also developed precipitin lines with antiserum taken from sensitized animals. A low molecular weight fraction was found to be completely reactive immunologically (UM2(a)), and appeared to have a molecular weight in the range of 2,000--4,000 as assessed by ultrafiltration and gel filtration studies.

Evidence for a common tumour-associated antigen in extracts of human bronchogenic carcinoma

Xeno-antiserum specific for antigenic components of bronchogenic carcinoma was raised in rabbits, by passively immunizing them to normal human lung antigens at the same time as immunization with a tumour extract from a squamous-cell carcinoma. Antiserum so raised contained minimal quantities of anti-normal antibody which could be removed by a single absorption with glutaral-dehyde-insolubilized normal lung extract. When tested by quantitative complement fixation with a panel of tumour extracts from surgical specimens, it was found that the antiserum gave positive complement fixation with all squamous-cell carcinoma extracts tested, and with some of the extracts from bronchogenic carcinomas of differing pathological types. The antiserum was essentially negative for pooled extracts from normal lung, liver and spleen but gave a weak positive reaction with an extract of pooled foetal lung tissue.

Identity of a T-lymphocyte inhibitor with mouse immunoglobulin in the serum of tumour-bearing mice

A component of the serum of tumour-bearing mice has been shown to be inhibitory to the immunological function of normal mouse T cells. This factor fractionates with monomeric immunoglobulin upon gel filtration. Studies were carried out utilizing goat antisera to the major immunoglobulin chains of mouse Ig (kappa, gamma, alpha and mu) mixed with the immunoglobulin-rich fraction of serum from normal mice and tumour bearers and passed through immunoadsorbent columns prepared with rabbit anti-goat immunoglobulin. Such studies showed that the inhibitory activity in tumour-bearing serum could be removed after treatment with anti-kappa, anti-gamma and anti-mu chain antisera but not by treatment with either anti-alpha chain or goat immunoglobulin. That the inhibitory activity of tumour-bearing immunoglobulin could be attributed to simple quantitative differences in the levels of IgM and IgG in the test samples was discounted by quantification of the amounts of immunoglobulins in normal and tumour-bearing sera.