Application of the international prognostic index in a study of Chinese patients with non-Hodgkin's lymphoma and a high incidence of primary extranodal lymphoma

BACKGROUND

Chemotherapy containing anthracycline is the standard initial treatment for aggressive non-Hodgkin's lymphoma (NHL), and the International Prognostic Index (IPI) is widely accepted as the standard tool for determining the prognosis of patients with this disease. However, the data on which the IPI was based primarily came from studies conducted in Western countries. It may not be directly applicable to Asian populations, in which the incidence of primary extranodal lymphoma (PENL) is known to be high.

METHODS

The authors conducted a retrospective study of 218 patients with aggressive NHL who were treated with chemotherapy. They analyzed the distribution of stage and pathology, prognostic factors, toxicity, and treatment outcome. The IPI was then applied and its ability to identify distinct prognostic groups tested.

RESULTS

Eighty-six patients (39.4%) had lymph node lymphoma (LNL) and 132 (60.6%) had primary extranodal lymphoma (defined as non-Hodgkin's lymphoma with primary presentation, bulk of disease, and histologic confirmation at an extranodal site). The most common primary extranodal sites were the stomach (22%) and Waldeyer's tonsillar ring (18.9%). The complete response rate of PENL patients to chemotherapy containing anthracycline was 52%, as compared with 64% of the LNL group. The 5-year survival rates for patients with LNL and PENL were 57.4% and 52.1%, respectively. The toxicity in the two patient groups was similar. Four of the prognostic factors in the IPI-age, serum LDH, performance status, and disease stage-predicted significantly different survival for PENL and LNL patients. However, the number of extranodal sites involved was not a significant predictive variable in PENL.

CONCLUSIONS

The IPI was applicable to this Chinese population in which the incidence of PENL was high, although the number of extranodal sites did not achieve statistical significance as a risk factor. A proposal for modification was made. Chemotherapy containing anthracycline was an effective treatment for both PENL and LNL patients.

Delivery of preventive healthcare to older African-American patients: a performance comparison from two practice models

While there is an increasing recognition by primary care providers of the importance of preventive health services (PHS), the delivery of such services has in general been substandard in many ambulatory care settings. Patient sociodemographic status and the structural and operational procedures of different clinic models are all believed to affect delivery of PHS. We conducted a 2-year, retrospective, sequentially randomized chart analysis of African-American patients above age 50, comparing primary, secondary, and tertiary PHS performance rates in two practice models: a medicine resident/faculty physician clinic (MR) and a nurse practitioner/faculty physician clinic (NP). Sociodemographics, disease profile, and PHS completion rates from 132 NP and 111 MR patient charts were abstracted. Apart from age, sociodemographic features were similar in both patient groups. While there were differences between clinics with regards to disease profiles (P < 0.05), and the higher number of diseases per patient (P < 0.0001) in the MR population, the NP collaborative practice had significantly better PHS performance. Rates of immunization (influenza/pneumococcal), pelvic/pap and prostate examinations, stool-guaiac testing, mammography, and functional assessment (activities of daily living, instrumental activities of daily living, and mental status testing) were > 90% in the NP and < 60% in MR patients. Although lower completion rates were found for dietary counseling (60%), auditory screening (36%), dental examination (41%), and obtaining advanced directives (24%) in the NP clinic, the rates were higher than those for the MR clinic. In this NP collaborative model, a high level of preventive health services was delivered while providing primary care to an older, inner city, African-American population of low socioeconomic means.

The advantages of the disease model

Health care professionals are interested in practical definitions that provide solutions to problems. There are many advantages to defining chemical dependence as a disease. This paper gives a health care professional clear directions regarding identifying the problem of chemical dependence and specifying a specific treatment plan for patients. We review the issues of personal responsibility, the moral model of addictions, and the neuropharmacology of the disease process, and advocate for the disease model as an effective, practical method for treating alcoholism and drug dependence.

Human immunodeficiency virus in semen arises from a genetically distinct virus reservoir

The reservoir of human immunodeficiency virus (HIV) in semen is unknown. Several lines of evidence suggest that semen HIV may not arise from the same reservoir of infection as peripheral blood. If true, the viral burden in the two compartments could be qualitatively and quantitatively different, a scenario of potentially profound significance for the design of effective strategies of treatment, disease monitoring, and infection containment. We report here that the ratio of infected to uninfected leukocytes in ejaculated semen specimens is highly discordant with paired blood samples, demonstrating that they derive from distinct populations of infected cells. In addition, infectious HIV was isolated from semen cells, but not from blood cells, of an individual on triple antiretroviral therapy; the absence of major resistance-conferring mutations in the semen virus indicates that it was replicating in isolation from the antiviral agents. The compartmentalization of blood and semen infection was further supported by genetic analysis of several infectious HIV clones isolated from semen cells and peripheral blood cells of another donor not on antiretroviral therapy. Protease gene sequence analyses revealed significant divergence of the two viral populations. These findings confirm the distinct compartmentalization of HIV in the semen of this study cohort, and support the concept that semen HIV arises from an isolated reservoir of infection that may function independently in the pathobiology of HIV disease.

Improving preventive health care in a medical resident practice

BACKGROUND

The ambulatory care resident practice is an opportunity to enhance the skills, knowledge, and attitudes for effective provision of preventive health services (PHS).

OBJECTIVE

To determine whether a required intervention at a university medical resident practice would lead to improved performance of 6 secondary PHS.

METHODS

A sequentially randomized chart analysis was performed at 2 clinics, a collaborative nurse practitioner practice (NP) and a resident practice (RP) to determine performance rate of secondary PHS (pelvic, prostate, and breast examinations, stool guaiac testing, mammography, and prostate-specific antigen determination). A significantly lower (36.9%) PHS performance rate was noted in the RP compared with 84.5% in NP for all 6 secondary PHS studied. An intervention was implemented in the RP: following every resident-patient clinic encounter a discussion and documentation of the patient's PHS status was required as part of the assessment and plans of management. At the end of 1 year the effect of this intervention on performance rates of the 6 PHS in the RP was analyzed.

RESULTS

There was a statistically significant difference (P < .001) between the PHS performance rates of NP and RP at the beginning. The intervention resulted in improved PHS performance rates in the RP; compared with the NP at the end of the study no statistical difference was noted between the groups.

CONCLUSIONS

Despite various task force recommendations, PHS performance rates are generally suboptimal in varied clinic settings, including those of resident practices in teaching hospitals. Physicians and residents believe in the importance of health maintenance but fall short of their ideal in practice. Interventions to improve performance rates have been described; we are detailing a simple, inexpensive, and practical method that achieved positive results.

Intracellular levels of SGP-2 (Clusterin) correlate with tumor grade in prostate cancer

Our previous observations in LNCaP cells in vitro demonstrated an association between apoptotic cell death resistance and SGP-2 (Clusterin) overexpression. Accordingly, we hypothesized that high levels of cellular SGP-2 would aid in identifying biologically aggressive prostate cancer cells with unique survival advantages. To test this hypothesis, 40 archival radical prostatectomy and/or biopsy specimens of varying grades of prostate cancer were subjected to immunohistochemical SGP-2 staining. The resulting epithelial stains were quantified subjectively on a scale of 1-3 by four independent observers. Benign prostatic epithelial cells from young donors served as controls and showed a consistently weak staining intensity. In contrast, prostate cancer specimens showed varying degrees of staining intensity that correlated with a Gleason pattern (P = 0.006). This correlation supports the hypothesis that protection from apoptotic death may account, in part, for biologically aggressive tumor behavior.

Glutamate and N-methyl-D-aspartate stimulate rat hypothalamic corticotropin-releasing factor secretion in vitro

It is known that in vivo excitatory amino acids (EAA) stimulate the hypothalamo-pituitary-adrenal axis. However their site of action is not fully understood. We investigated the possibility of a direct action of EAA on the secretion of the major adrenocorticotropin hormone (ACTH) secretagogue: corticotropin-releasing factor (CRF) from incubated rat hypothalamic slices. N-methyl-D-aspartic acid (NMDA) or L-glutamate (1 x 10(-7) to 1 x 10(-3) M) stimulated in a dose-dependent fashion CRF release. The maximal effect was obtained at a concentration of 1 x 10(-4) M for both drugs. The IC50 was 1.3 x 10(-5) M and 3.3 x 10(-5) M for NMDA and L-glutamate, respectively. Incubation with 2.5 x 10(-4) M D-2-amino-5-phosphonovalerate (a NMDA receptor antagonist) or 2-amino-4-phosphonobutyrate (a metabotropic receptor antagonist) was without significant effect on basal CRF secretion and completely blocked the increase in CRF release induced by 5 x 10(-5) M NMDA or L-glutamate, respectively. Incubation with 1 x 10(-4) M kainate or 0.5 x 10(-4) M AMPA did not change basal CRF secretion. Incubation with 2 x 10(-4) M gamma-D-glutamylglycine (a specific antagonist of kainate and AMPA receptor) had no effect under basal conditions or during exposure to kainate or AMPA. Our data demonstrate that EAA could stimulate directly CRF secretion, by an action through NMDA and metabotropic receptors, but not kainate or AMPA receptors. These findings may be relevant to the regulation of the hypothalamo-pituitary adrenal axis, both under basal conditions and during exposure to stress.

Effect of excitatory amino acids on rat hypothalamic somatostatin secretion in vitro

We studied the effect of various agonists of excitatory amino acid (EAA) receptor subtypes on somatostatin (SRIF) release from incubated rat hypothalamic slices. N-Methyl-D-aspartic acid (NMDA) and L-glutamate (1 x 10(-7) to 1 x 10(-3) M) stimulated, in a dose-dependent fashion, SRIF release. The maximal effect was obtained at a concentration of 1 x 10(-4) M for both drugs. The IC50 was 3.2 x 10(-5) M and 2.1 x 10(-5) M for NMDA and L-glutamate, respectively. Incubation with 2.5 x 10(-4) M D-2-amino-5-phosphonovalerate (a NMDA receptor antagonist) or 2-amino-4-phosphonobutyrate (a metabotropic receptor antagonist) was without significant effect on basal SRIF secretion and completely blocked the increase in SRIF release induced by 5 x 10(-5) M NMDA or L-glutamate, respectively. Incubation with 1 x 10(-4) M kainate or 0.5 x 10(-4) M alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) did not change basal SRIF secretion. Incubation with 2 x 10(-4) M gamma-D-glutamylglycine (a specific antagonist of kainate and AMPA receptors) had no effect under basal conditions or during exposure to kainate or AMPA. Our data demonstrate that EAAs stimulate SRIF secretion in vitro, by an action through NMDA and metabotropic receptors but not kainate or AMPA receptors.

Amino acids and ammonia in the cerebral cortex, the corpus striatum and the brain stem of the mouse prior to the onset and after a seizure induced by hyperbaric oxygen

The contents of amino acids (AA) and ammonia (NH3) were measured in corpus striatum, brain stem and cerebral cortex of two strains of mice exposed to hyperbaric oxygen (HBO). Mice of the HBO-sensitive strain (CD1) were exposed to 600 kPa O2 for 24 min versus 90 min for mice of the normal C57 strain, so that 50% of the mice in both strains developed a generalized convulsion. In the cortex of exposed but unconvulsed (EXUN) C57 mice, the contents of taurine, glutamine and NH3 increased while that of GABA decreased when compared to control mice. In the CD1 mice, NH3 content was increased while that of Asp decreased. After a convulsion, NH3 was increased in both strains, the AA contents returned to normal in C57 but Asp remained low in CD1 mice. Somewhat similar changes occurred in the striatum except that NH3 levels were less affected while GABA ones were significantly decreased in the CD1 mice exposed to HBO, whether convulsed or not. In the EXUN brain stem, Asp and Glu contents decreased. These decreases were greater in C57 on a percentage basis than in CD1 mice. GABA content was decreased in the C57 strain. After a convulsion, Asp and Glu levels remained low and NH3 accumulated in CD1 whereas in C57 only the Glu level was decreased. The cortical and striatal changes may indicate a lesser GABA supply in C57 strain and some Asp release in CD1 strain. In the brain stem of both strains, Asp and Glu release is possible in addition to GABA in C57 strain.(ABSTRACT TRUNCATED AT 250 WORDS)

[Radiologic visibility of breast fibroadenomas]

From a clinical point of view, all mammary fibroadenomas are similar. However some of them are not visible in mammograms, phenomenon probably related to glandular density. Aiming to elucidate whether the lack of visibility is caused by the glandular density or by tumor itself, a three stage study was performed. In 201 cases the mammographic visibility of fibroadenomas was determined and correlated with patient's age, the presence of fibrocystic disease and tumor histological type; after surgical excision, 18 fibroadenomas were sliced into 5 mm thick samples and X rayed to determine their visibility; finally 2 visible and 2 non visible tumors were calcinated at 550 degrees C and their ashes subjected to X-ray diffraction analysis. Twenty two percent of fibroadenomas were not visible on mammography, this percentage was higher for intracanalicular tumors, in younger women and in the presence of fibrocystic disease. Sixteen percent of excised and sliced tumors were not visible on X rays. Also, differences were found in X-ray diffraction studies between visible and invisible tumors, probably related to NaCl and KCl tumor content.

Management of recurrent priapism with epinephrine self-injection and gonadotropin-releasing hormone analogue

A case of recurrent priapism in a young black man without sickle cell anemia is reported. Due to almost daily episodes of prolonged painful erections, the patient was instructed in intracorporeal injection using an epinephrine self-injection kit, which provided complete detumescence on 31 occasions. The patient refused surgical intervention and was treated with monthly intra-muscular gonadotropin-releasing hormone analogue. Priapism episodes completely abated by the second and final monthly gonadotropin-releasing hormone analogue injection without recurrence during 4 months of followup. Normal erectile function was maintained during and after gonadotropin-releasing hormone analogue therapy. Epinephrine self-injection and gonadotropin-releasing priapism.

Intramuscular versus oral antibiotic therapy for the prevention of meningitis and other bacterial sequelae in young, febrile children at risk for occult bacteremia

Because studies of the treatment of children with occult bacteremia have yielded conflicting results, we compared ceftriaxone with amoxicillin for therapy. Inclusion criteria were age 3 to 36 months, temperature > or = 39 degrees C, an acute febrile illness with no focal findings or with otitis media (6/10 centers), and culture of blood. Subjects were randomly assigned to receive either ceftriaxone, 50 mg/kg intramuscularly, or amoxicillin, 20 mg/kg/dose orally for six doses. Of 6733 patients enrolled, 195 had bacteremia and 192 were evaluable: 164 Streptococcus pneumoniae, 9 Haemophilus influenzae type b, 7 Salmonella, 2 Neisseria meningitidis, and 10 other. After treatment, three patients receiving amoxicillin had the same organism isolated from their blood (two H. influenzae type b, one Salmonella) and two from the spinal fluid (two H. influenzae type b), compared with none given ceftriaxone. Probable or definite infections occurred in three children treated with ceftriaxone and six given amoxicillin (adjusted odds ratio 0.43, 95% confidence interval 0.08 to 1.82, p = 0.31). The five children with definite bacterial infections (three meningitis, one pneumonia, one sepsis) received amoxicillin (adjusted odds ratio 0.00, 95% confidence interval 0.00 to 0.52, p = 0.02). Fever persisted less often with ceftriaxone (adjusted odds ratio 0.52, 95% confidence interval 0.28 to 0.94, p = 0.04). Although the difference in total infections was not significant, ceftriaxone eradicated bacteremia, prevented significantly more definite focal bacterial complications, and was associated with less persistent fever.

Effect of streptozotocin-induced diabetes on somatostatin receptors in the anterior pituitary, hypothalamus and cerebral cortex of the male rat

In order to better understand the mechanisms underlying the reduction in GH secretion in diabetic rats, we have characterized and measured SRIH receptors in the hypothalamus and anterior pituitary gland 5 and 9 days after induction of diabetes in the rat. Experimental diabetes was induced by an intraperitoneal injection of streptozotocin (STZ) at a dose of 65 mg/kg. Basal plasma GH was significantly reduced in diabetic rats. Chronic insulin replacement therapy partly restored plasma GH and blood glucose levels in these animals. A significant reduction in SRIH receptor concentrations was demonstrated in the hypothalamus and anterior pituitary gland, 5- and 9- days after STZ injection. These changes were not significantly corrected by insulin replacement. Cerebral cortex SRIH receptor concentrations were unaffected by experimental diabetes. We conclude that hypothalamic and pituitary SRIH receptor levels are lowered in diabetic rats. These changes may contribute to aberrant GH secretion in diabetes and they indicate that pituitary sensitivity to exogenous somatostatin should be tested in diabetic patients.

Effect of one hyperbaric oxygen-induced convulsion on cortical polyamine content in two strains of mice

In rat striatum, after one hyperbaric oxygen (HBO)-induced convulsion, polyamine changes are found that could promote N-methyl-D-aspartate (NMDA) activation. In the HBO-sensitive CD1 mouse, unlike in the common C57 strain, there is some support for NMDA activation after the HBO seizure. We measured PA cortical content before and after the first HBO-induced convulsion (about 608 kPa O2) in CD1 and C57 strains. Putrescine, spermidine and spermine were dansyl derived and analysed by HPLC. Exposure to HBO significantly increased putrescine content only in CD1 though a similar trend was observed in C57. No further increase was observed after convulsion whatever the strain. There were no significant changes in spermidine or spermine to support NMDA activation. Therefore, putrescine increase in CD1 cortex could reflect the free radical formation that is known to be greater in CD1 than in C57 mouse. Attempts to increase putrescine levels before HBO exposure hastened HBO-induced convulsion, less than spermidine or spermine. Because of physiological polyamine interconversion, additional experiments with indirect manipulation of putrescine levels and study of their time-course would precise these preliminary reports on putrescine and HBO.

Desipramine does not alter plasma GABA in patients with major depression

Low plasma GABA is a biological marker for depression in a subset of patients tested. Plasma GABA has been shown to reflect brain GABA activity. This marker has many characteristics of a trait marker for depression, including stability with time, and lack of influence by coincident factors such as gender, season, time, activity or diet. We here report that plasma GABA remained stable after 4 weeks of treatment with desipramine in patients with major depression. Since the levels of plasma GABA did not change with time, nor with clinical improvement, plasma GABA is not a state marker of depression.

Evaluation and treatment of post-traumatic stress disorder

Post-traumatic stress disorder (PTSD) is a common anxiety disorder seen by general practice physicians as well as by specialists. The authors review current assessment criteria, psychotherapy procedures, and psychopharmacological management of PTSD patients.

Comparison of vasovasostomy techniques in rats utilizing conventional microsurgical suture, carbon dioxide laser, and fibrin tissue adhesives

An evaluation of vas reanastomoses in rats comparing suture only, carbon dioxide (CO2) laser-assisted, and fibrin-based tissue adhesive was performed in our laboratory. A cohort of 60 known fertile male Sprague Dawley rats initially underwent lower midline abdominal exploration and transection of their vas deferens bilaterally, followed by immediate microsurgical vasovasostomy by one of the three experimental methods. All groups initially had the severed vasa ends coapted by two or three transmural (mucosa through serosa) sutures of 10-0 nylon under an operating microscope. The conventionally sutured group had an additional four to six nylon 10-0 sutures placed externally in the serosa only to complete the anastomosis. The CO2 laser-assisted group underwent laser welding with denaturation of the serosa to seal the anastomosis. A fibrin-based tissue adhesive, produced by combining human cryoprecipitate and thrombin, was placed topically over the coapted vas ends to seal the anastomosis in the third group. Postoperative evaluation revealed similarities among the three surgical groups with the fibrin-based tissue adhesive group resulting in the highest patency rate (89%) and pregnancy rate (85%) as well as the lowest granulation rate (18%) and shortest operative time (27 minutes). The laser-assisted group resulted in the lowest pregnancy rate (68%), while the sewn anastomosis group had the lowest patency rate (76%). Both laser-assisted and conventionally sewn vasectomy reversals required significantly longer operative time (39 and 46 minutes, respectively) compared with the fibrin-based tissue adhesive-assisted procedures (p < 0.01). This study provides evidence that alternative microsurgical techniques may be utilized to perform uncomplicated, expeditious, and successful vasectomy reversals.

Cardiosynchronous limb compression: effects on noninvasive vascular tests and clinical course of the ischemic limb

Some patients with chronic arterial obstruction of the limbs may still suffer the consequences of advanced tissue ischemia, including ulceration and rest pain, and face threatened limb loss in spite of available surgical, pharmacologic, and other treatments. Additional therapeutic modalities were thus sought to accomplish limb salvage. A literature review indicated that most reports on R-wave-triggered circumferential limb compression (cardiosynchronous limb compression [CSC]) demonstrate its ability to augment limb arterial blood flow and improve ischemic limbs. To determine the device's efficacy and safety, and possibly confirm earlier positive reports, a systematic study was undertaken, using older, as well as newer, more electronically reliable CSC devices. The present study was designed to determine the following: 1. objectively, by noninvasive vascular tests, changes in limb blood flow, if any, by CSC; 2. clinical effects of CSC, if any, on the ischemic limb; 3. duration of CSC-induced limb improvements, if any; 4. side effects or safety of CSC. The study demonstrated that CSC treatments: 1. caused increased limb blood flow as determined by increased ankle/arm indices and hallux photoplethysmograph waveform amplitudes during treatments; 2. led, in most cases, to improvement in or resolution of the presenting ischemic problem (eg, ulcer, cellulitis, rest pain); 3. induced limb improvements that persist for up to seven years 4. caused no adverse side effects.

Effect of diabetes on in vivo and in vitro hypothalamic somatostatin release

In order to better understand the mechanisms underlying the reduction in growth hormone (GH) secretion in diabetic rats, we studied hypothalamic somatostatin secretion both in vivo (into hypophysial portal blood) and in vitro (from hypothalamic fragments) 5, 9 and 30 days after induction of diabetes. Experimental diabetes was induced by an intraperitoneal injection of streptozotocin (STZ) at a dose of 65 mg/kg. Basal plasma GH was significantly reduced in diabetic rats at all stages. Somatostatin levels in hypophysial portal blood was unaffected in 5-day STZ-diabetic rats and significantly increased 9 days after STZ administration. Chronic insulin replacement therapy in diabetic animals partly normalized somatostatin levels as well as plasma GH and glucose levels. A good correlation was observed between in vivo and in vitro experiments. Indeed, somatostatin release from hypothalamic fragments did not change 5 days after STZ-induced diabetes and significantly increased 9 and 30 days after STZ administration. The in vitro increase in hypothalamic somatostatin secretion was observed in 10 as well as in 33 mM glucose concentration in the incubation medium. In the same experiment, the in vitro hypothalamic corticotropin-releasing factor secretion was lowered 5 and 9 days after diabetes induction. We conclude that hypothalamic somatostatin release increases in diabetic rats. These changes may contribute to the reduction in GH secretion in these animals. However, since these changes occur after the onset of plasma GH decrease, a factor(s) other(s) than somatostatin may play a causal role in the reduction in GH secretion.

Prognostic factors in patients with metastatic colorectal cancer receiving 5-fluorouracil and folinic acid

We have reported that 5-fluorouracil (5-FU) and folinic acid increased response rate and survival in patients with metastatic colorectal cancer. Now we have analysed prognostic factors for response, toxicity, survival and time to progression. The variables used for survival and response were treatment centre, treatment, age, sex, Eastern Cooperative Oncology Group (ECOG) performance status (PS), site of disease, previous radiotherapy, site of primary, disease-free interval, initial alkaline phosphatase (AP), albumin (A), lactate dehydrogenase (LDH) and aspartate aminotransferase (SGOT). The significant independent variables for survival were PS of 2 or more, initial albumin and SGOT, and treatment received, in order of importance. The relative risk of death when patients received 5-FU/folinic acid was 60% of that of patients receiving 5-FU alone. The variables predictive of response were treatment and PS. The variables used for analysis of toxicity were age, treatment centre, treatment, sex, tumour response, PS, number of courses, SGOT, AP and albumin. Treatment was found to be predictive of toxicity. Thus, baseline albumin and SGOT, and 5-FU/folinic acid treatment are significant determinants of survival, 5-FU/folinic acid and PS of 2 or more are major determinants of response and no clinical parameter could be identified as a predictor of toxicity.

Alcohol and breast cancer risk--putting the current controversy into perspective

The potential association of alcohol intake with breast cancer risk is currently being debated in the literature and a clear consensus of opinion has not emerged. Clarification of the issues surrounding this controversy would be helpful in developing recommendations for the general public regarding alcohol use. A review of the available evidence regarding the association of alcohol with breast cancer is presented followed by an application of the Bradford Hill criteria for causal inference to this data to examine the existence and nature of the association of alcohol with breast cancer risk. Results of published studies demonstrated a weak association of alcohol with breast cancer risk that was consistent only for relatively high levels of intake (more than 1 or 2 drinks daily). Increasing daily intake was associated with increased risk, but the association was not linear. Criteria relating to temporality and analogy to other causal associations were satisfied while inconsistent evidence was available for those relating to epidemiologic and biologic sense. The criterion for specificity was not satisfied and no experimental evidence was available. It is concluded that insufficient evidence exists to support a causal association of alcohol consumption with breast cancer risk. Further research is recommended to resolve conflicting evidence and to provide additional evidence where needed. In the meantime, recommendations that women should reduce their consumption of alcohol beyond existing guidelines to modify breast cancer risk are probably premature.

Large asymptomatic antrolith of the maxillary sinus. Report of a case

A case of an unusually large antrolith of the maxillary sinus is presented. Because of the size of the mass, benign neoplasms were considered in the differential diagnosis. Surgery was the treatment of choice, and recurrence of the lesion is not expected.

Acute urinary retention secondary to Herpes simplex meningitis

We report a case of acute urinary retention in a 24-year-old man with Herpes simplex meningitis without genital lesions. Since the differential diagnosis in young patients who present with acute urinary retention also includes multiple sclerosis, lumbosacral disk herniation, rheumatological disorders and drug intoxication, a thorough history and careful neurological examination are of paramount importance in distinguishing these syndromes. As part of a directed neurological evaluation prompt performance of lumbar puncture is indicated; a lymphocytic pleocytosis is suggestive of herpetic meningitis. Culture of Herpes simplex virus from the cerebrospinal fluid should be attempted. We recommend conservative management only, typically with intermittent catheterization, since bladder function usually normalizes within 10 to 14 days.

Cognition and metacognition at extreme altitudes on Mount Everest

The FACTRETRIEVAL2 test battery, which assesses both retrieval of general information from memory and metacognition about that retrieval, was administered to people before and after a recent expedition to Mount Everest and at extreme altitudes above 6,400 m (higher than any mountain in North America or Europe). The major findings were as follows: First, the same extreme altitudes already known to impair learning did not affect either accuracy or latency of retrieval, and this robustness of retrieval occurred for both recall and forced-choice recognition. Second, extreme altitude did affect metacognition: The climbers showed a decline in their feeling of knowing both while at extreme altitude and after returning to Kathmandu (i.e., both an effect and an aftereffect of extreme altitude). Third, extreme altitude had different effects than alcohol intoxication (previously assessed by Nelson. McSpadden, Fromme, & Marlatt, 1986). Alcohol intoxication affected retrieval without affecting metacognition, whereas extreme altitude affected metacognition without affecting retrieval; this different pattern for extreme altitude versus alcohol intoxication implies that (a) hypoxia does not always yield the same outcome as alcohol intoxication and (b) neither retrieval nor metacognition is strictly more sensitive than the other for detecting changes in independent variables.

Use of thermography in the differential diagnosis of phylloides tumour

Thermography can be used as a method of diagnosing breast masses. We report our results of its use in the differential diagnosis of fibroadenoma from phylloides tumours (n = 47 and 20 respectively). Thermographic resolution (Th) and the difference in temperature between the tumour and a similar zone in the contralateral breast (delta 2) were compared. Thermograms were class Th1 (with a similar thermal pattern in both breasts without hypervascularization or hot points) and Th2 (with hypervascularization or a hot area with a thermal difference with the same area in the opposite breast (delta 2) of less than 2 degrees C) in most (95.7 per cent) of the patients with fibroadenoma and were class Th5 (having one or more pathological sign) in 85 per cent of the patients with phylloides tumours. Patients with phylloides tumours had a mean delta 2 of 2.99 degrees C whereas most of the patients with a fibroadenoma showed no difference in temperature. Their mean delta 2 was 0.2 degrees C (P less than 0.0005). We conclude that thermography helps in differential diagnosis between a fibroadenoma and a phylloides tumour.

The use of collagen membrane barriers in conjunction with combined demineralized bone-collagen gel implants in human infrabony defects

The present study evaluated the clinical efficacy of a combined graft of autolysed antigen-extracted allogeneic (AAA) bone and microfibrillar collagen (Zyderm) covered with a resorbable collagen membrane in human infrabony defects. The results were compared at 1 year with debrided controls, AAA bone grafts alone, combined AAA bone-collagen grafts (without membrane), and debrided defects covered only with collagen membranes. Ten adult patients having moderate periodontitis and one or more radiographically detectable angular defects probing 6 mm to 7 mm in each quadrant were included. Preoperative measurements of clinical attachment, probing depth, and recession were taken and compared at 1 year following surgery. Measurements at the time of surgery and at 1 year re-entry evaluated osseous defect fill and crestal changes. Each patient received the 5 treatment modalities. Treatment results per patient were used for a series of 2-way analyses of variance. When a significant difference was found, a Student-Newman-Keuls multiple range test was used to determine which treatments were statistically different (0.05 probability level) from each other. All treatment modalities showed improvement over the debrided controls. Similar advantages to using bone-collagen grafts with and without membranes were found in reducing probing depths and gaining new attachment. Significant differences were found when comparing the multifaceted bone graft collagen-membrane technique to all others in achieving superior defect fill. Ninety three percent of all defects treated resulted in 50% or greater fill.

Modern concepts of tonsillectomy

Tonsillectomy and adenoidectomy is still the most commonly performed surgical procedure in North America. The indications for surgery are constantly debated and seem to vary subjectively. The merits of performing a tonsillectomy for what is an essentially benign condition must be taken in perspective and require a more scientific approach. It is important to understand the pathophysiology of Waldeyer's ring and the changes brought about by recurring infections in the region. Treatment protocols vary, as do physician attitudes. Many tonsillectomies are still performed by surgeons other than otolaryngologists: for example, by family physicians and general surgeons. The authors discuss the indications and the scientific basic for tonsillectomy.

Chronic sinusitis

Paranasal sinuses, which communicate with the nasal passages through the sinus ostia, are essentially sterile structures, sterility being maintained by a healthy epithelium with normal actively beating cilia. Irritants, including viruses and bacteria, are trapped in mucus and cilia to allow the clearance of sinuses through the natural ostia into the nasal cavity. Interference with this normal physiological function results in inflammation and infection within the sinus cavities. All of the sinuses are subjected to the same environmental as well as physiological stimuli; thus it is uncommon for a single sinus to be infected and for the others to remain entirely normal. Allergic and non-allergic vasomotor rhinitis should be differentiated from chronic bacterial rhinosinusitis. The understanding of these diseases cannot be separated from the physiological function of the sinus mucosa.

CT appearance of an oncocytic papillary cystadenoma of the larynx

The CT appearance of an oncocytic papillary cystadenoma of the right laryngeal false cord is presented. This unusual tumor of the larynx with similar CT appearance to that of a cyst of the laryngeal saccule is discussed.

Cognition and metacognition at extreme altitudes on Mount Everest

The FACTRETRIEVAL2 test battery, which assesses both retrieval of general information from memory and metacognition about that retrieval, was administered to people before and after a recent expedition to Mount Everest and at extreme altitudes above 6,400 m (higher than any mountain in North America or Europe). The major findings were as follows: First, the same extreme altitudes already known to impair learning did not affect either accuracy or latency of retrieval, and this robustness of retrieval occurred for both recall and forced-choice recognition. Second, extreme altitude did affect metacognition: The climbers showed a decline in their feeling of knowing both while at extreme altitude and after returning to Kathmandu (i.e., both an effect and an aftereffect of extreme altitude). Third, extreme altitude had different effects than alcohol intoxication (previously assessed by Nelson. McSpadden, Fromme, & Marlatt, 1986). Alcohol intoxication affected retrieval without affecting metacognition, whereas extreme altitude affected metacognition without affecting retrieval; this different pattern for extreme altitude versus alcohol intoxication implies that (a) hypoxia does not always yield the same outcome as alcohol intoxication and (b) neither retrieval nor metacognition is strictly more sensitive than the other for detecting changes in independent variables.

Corticotropin-releasing factor release from in vitro superfused and incubated rat hypothalamus. Effect of potassium, norepinephrine, and dopamine

We have compared the release of CRF induced by potassium depolarization, noradrenaline or dopamine as monitored either during superfusion of mediobasal hypothalamus or during incubation of whole hypothalamus. The superfusion device was improved in order to prevent gas leakage and to keep constant pO2 and pCO2 in the superfusion chamber. Basal CRF secretion as well as KCl- and norepinephrine-induced CRF release were comparable in superfusion and incubation experiments. Pharmacological investigations suggest that the stimulatory effect of norepinephrine on CRF release is mediated mainly through alpha 1 and alpha 2 adrenergic receptors, and partially through beta receptors.

Human erythrocyte adhesion and spreading on protein-coated polymer surfaces

Protein adsorption is the first event which occurs when polymer surfaces are exposed to blood. The adsorption of proteins modifies the surface properties of the substrates and therefore influences subsequent cell-surface interactions. In an attempt to elucidate the fundamental mechanisms governing cell-proteinated-surface interactions, the extent of fresh human erythrocyte adhesion and spreading on protein-coated surfaces was examined. Five human serum proteins (albumin, fibrinogen, immunoglobulin G, fibronectin, and transferrin) were used at bulk concentrations ranging from 0.01 mg/mL to 50 mg/mL. Polymer substrates covering a wide range of wettability were employed. Protein adsorption significantly reduces erythrocyte adhesion and spreading on all test surfaces with minimum adhesion observed on fibrinogen: IgG greater than albumin greater than fibronectin greater than transferrin greater than fibrinogen. The extent of these effects is dependent on the nature of the adsorbed protein, the protein bulk concentration, and the surface properties of the underlying polymer substrates.

Racial differences in drug response: isoproterenol effects on heart rate following intravenous metoprolol

Healthy young black men and white men received single intravenous doses of metoprolol (0.07 mg/kg) or participated in an isoproterenol sensitivity study before and after metoprolol (0.07 mg/kg followed by 50 micrograms/min) in a randomized, crossed-over fashion. Noncompartmental pharmacokinetic parameters were calculated. The dose of isoproterenol versus change in heart rate response curves were constructed, and comparisons of dose ratio, ED50, Emax, and Ka, with the apparent association constant for metoprolol binding to beta 1-receptors, were made. There were no pharmacokinetic differences observed between the groups. The predicted Emax for the black group was 52.7 +/- 8.7 beats/min at a metoprolol concentration of 29.8 +/- 6.1 ng/ml, which was higher (p less than 0.05) than that in the white group, i.e., 43.7 +/- 7.3 beats/min at a concentration of 27.6 +/- 9.1 ng/ml. There were no differences in dose ratio, ED50, or Ka. The racial differences in beta 1-receptor responses to exogenous isoproterenol following metoprolol can simply be explained by an increase in beta 1-receptor activity in the black subjects, assuming homogeneity in cardiac beta 2-receptor responses.

Human suppressor factors constitutively produced by T-T cell hybridomas: functional and biochemical characterization

We have recently developed a new method (Hybridoma 6:589, 1987) for the generation of human T-T cell hybrids. This method is based on a new selection procedure that involves cloning the hybrids in soft agar, screening by HLA-typing or appropriate functional tests and recloning by limiting dilution. T-T cell hybrids were separated from the parent line on the basis of their ability to form colonies in soft agar, whereas the parent lymphoblastoid T cell lines did not. HAT medium was not used in our selection procedure. Using this method, we have succeeded in developing human T-T cell hybrids (as determined by HLA-typing) constitutively producing B cell growth factor (BCGF) (Hybridoma 6:589, 1987) or suppressor factors. These hybrids were obtained by fusing MLC or Con A T cell blasts with cells from the Molt 4 or Jurkat lymphoblastoid T cell lines. T-T cell hybridomas, derived by fusing Con A-stimulated lymphocytes with cells from the Jurkat T cell line, produced suppressor factors inhibiting: (1) proliferative response in vitro of human peripheral blood mononuclear leukocytes to mitogens and to allogeneic cells in mixed lymphocyte culture; and (2) immunoglobulin synthesis and secretion by mononuclear leukocytes in the PWM-induced differentiation system in vitro. A suppressor factor with these inhibitory properties was also identified in supernatants of the Jurkat T cell line. These suppressor factors were ammonium sulphate precipitable, pH 2 labile, non-dialyzable and they were inactivated by treatment at 56 degrees C for 30 minutes. They exhibited a molecular weight in the range of 50,000-70,000, as determined by gel filtration, and were not gamma or alpha interferon or lymphotoxin/TNF. They did not lyse human lymphoblastoid tumor cell lines nor did they affect the viability and cell numbers of human mononuclear cells even after prolonged incubation (88 hr). They appeared to be cytostatic rather than cytotoxic molecules. The Jurkat suppressor factor is different from those produced by the hybrids on the basis of: (a) different isoelectric points; and (b) the ability of the Jurkat factor to arrest proliferation to PHA of human mononuclear cells in the S phase, whereas the 160 and 169 factors arrest proliferation at the G1 phase of the cell cycle. Certain of these suppressor factors (produced by the hybrids 153, 160, 170, and the Jurkat T cell line) also inhibited proliferative responses of mouse lymphocytes in vitro. In contrast, suppressor factors produced by the 169 and 77 hybrids did not inhibit any murine responses.

Bacterial tracheitis in children

We examined the records of 14 patients aged 7 months to 10 1/4 years who were treated for bacterial tracheitis from May 1982 to December 1987; the management protocol for 13 of the patients included the use of nasotracheal intubation. The infection was caused by Staphylococcus aureus in seven, Haemophilus influenzae in three, Branhamella catarrhalis in one and Streptococcus pneumoniae in one. Both H. influenzae and B. catarrhalis were isolated in another patient, and no organism was found in the remaining patient. In addition to the bacteria, viruses were cultured from the tracheal secretions of two patients. The mean duration of intubation was 7.6 days and of hospital stay 9.2 days. Twelve of the cases occurred during the cold months of the year (October to March). Of the three deaths only one occurred in the pediatric intensive care unit and was due to severe bronchospasm and an air leak that caused bilateral pneumothorax and pneumomediastinum. In one patient subglottic stenosis developed that necessitated tracheostomy. Healing began 5 to 9 days after the onset of symptoms, as demonstrated with the use of repeated fibreoptic bronchoscopy. We found that the airway could be safely managed with the use of a nasotracheal tube. Bronchoscopy helped to confirm the diagnosis, to remove adherent secretions and to monitor the course of the disease. The ventilation tube can be removed after the patient's temperature returns to normal, if there is an air leak around the tube, if the quantity and viscosity of the secretions decrease and if healing is observed at bronchoscopy.

Preservation of intermediary metabolism in saponin-permeabilized rat adipocytes

A unique permeabilized adipocyte model is described in which vigorous intracellular intermediary metabolism is preserved through both the pentose and glycolytic-Krebs pathways following saponin-induced pore formation in plasma membranes. Upon addition of appropriate cofactors, the cells metabolize both glucose and glucose 6-phosphate at rates which are severalfold greater than control (membrane-intact) cells. Saponin is shown to mediate these metabolic effects solely by creating membrane pores through which substrate influx occurs. This cell model provides an unprecedented opportunity to examine intermediary metabolism in situ because it permits the entry into the cytosol of previously restricted substrates, modifiers, and radiolabeled compounds. By circumventing the glucose transporter while, for the most part, preserving plasma membrane integrity, these metabolically active, porous adipocytes may permit the direct exploration of postinsulin receptor glucose metabolism by various hormones or drugs.

Proliferation of leukemic B cells in response to SAC and anti-mu. Evidence for different modes of action and comparison to proliferation and differentiation induced by conditioned medium

We investigated the proliferative responses and immunoglobulin production of highly purified E-rosette negative largely leukemic B cells from patients with CLL to Staphylococcus aureus Cowan I (SAC) or to SAC in combination with anti-mu or conditioned medium (CM). The latter was derived by stimulating human peripheral blood mononuclear leukocytes with PHA. We observed: (1) that purified E-rosette negative largely leukemic B cells from 25% (five out of 20) of the patients exhibited proliferative responses to SAC; (2) inhibition of SAC-induced proliferation by anti-mu in certain patients, whereas synergism between SAC and anti-mu in inducing proliferative responses in others; (3) the lack of synergism between SAC and CM in inducing proliferative responses, which is in contrast to the strong synergism that was observed between anti-mu and CM in inducing proliferation; and (4) induction or enhancement by SAC alone of Ig production by largely leukemic B-cell populations from few patients with CLL and purified tonsillar B lymphocytes, but not peripheral blood B cells from normal donors. These results suggest that SAC and anti-mu induce proliferation of B cells by different mechanisms and that B-cell proliferation and differentiation is dependent not only on the mitogen but also on the activation state of the cells.

Further studies on the effect of glucose concentrations and other oxidizable substrates upon ionic gradients and in vitro somatostatin release from rat mediobasal hypothalamus

During in vitro incubation of rat mediobasal hypothalamus (MBH), potassium and sodium gradients were high in the presence of glucose, pyruvate, lactate or the mixture glucose and pyruvate; in the absence of substrate, the ionic gradients were markedly lowered and corresponding somatostatin release from MBH was maximal. The specific effect of glucose on somatostatin release from MBH was tested under normal tissue polarization, i.e. in the presence of pyruvate. Under these more physiological conditions, somatostatin release was submaximal and inversely related to glucose concentrations (within the range 0-7 mM).

Inhibition of spontaneous proliferation of human leukemic B cells from patients with chronic lymphocytic leukemia by anti-mu antibodies

In a monoclonal system, F(ab')2 fragments of rabbit anti-mu antibody (anti-mu) were found to inhibit the proliferation and differentiation of highly purified E-rosette-negative largely leukemic B cells from two patients with chronic lymphocytic leukemia (CLL). Leukemic B cells from these two patients, in contrast with the majority of patients with CLL, exhibited high spontaneous proliferation in culture medium alone. This spontaneous proliferation was significantly inhibited by moderate concentrations of anti-mu (10-50 micrograms/ml). In contrast, lower concentrations of anti-mu (0.6-1.2 micrograms/ml) induced proliferation of leukemic B cells. Conditioned media (CM), derived by stimulation of human peripheral blood mononuclear leukocytes with phytohemagglutinin, induced significant proliferation of these leukemic B cells. This induced proliferation at optimal CM concentrations was inhibited by anti-mu. However, at high CM concentrations, which did not cause significant proliferation, synergism between CM and anti-mu in inducing proliferation was observed. Stimulation of spontaneously proliferating leukemic B cells with CM resulted in differentiation into cells synthesizing and secreting immunoglobulin M (IgM) but not IgG. This IgM production was also inhibited by anti-mu.

Induction of proliferation and differentiation of leukaemic B cells from patients with chronic lymphocytic leukaemia by anti-mu and conditioned medium

We investigated the growth and differentiation of leukaemia B cells from patients with B-cell chronic lymphocytic leukaemia (CLL) in response to proliferation and differentiation factors present in conditioned medium and to anti-immunoglobulin antibodies. Highly purified E-rosette negative (E-) B cells from 5 out of 15 patients with CLL exhibited moderate proliferative responses to 10 or 50 micrograms/ml of F(ab)'2 fragments of rabbit anti-human mu-chain specific antibody. Conditioned medium (CM), derived by stimulating human peripheral blood mononuclear leucocytes with PHA, induced significant proliferative responses of purified E- cells in 13 out of 14 patients examined. The extent of these proliferative responses varied substantially, and was in the range of 2.6- to 91-fold. Stimulation of purified E- cells from patients with CLL with both anti-mu and CM resulted in significant proliferation in all 15 patients examined. These responses were significantly higher than those induced by CM alone (P less than 0.02). Synergism between CM and anti-mu in inducing proliferative responses was observed in 11 out of 15 patients. Largely leukaemic B cell populations expressing on the cell surface more than one immunoglobulin heavy-chain isotype, exhibited significantly higher (P less than 0.009) proliferative response to CM and anti-mu than those expressing IgM only. Highly purified E-peripheral blood or tonsil lymphocytes from all normal donors examined responded by proliferation to anti-mu alone or to CM alone. Synergism in inducing proliferative responses was also observed when the cells were stimulated with both CM and anti-mu. In addition to inducing proliferative responses, culture with CM of purified E-rosette negative, largely leukaemic, B cells from patients with CLL for 6 days at 37 degrees C resulted in differentiation into immunoglobulin synthesizing and secreting cells. Synthesis and secretion of IgM were observed in 7 out of 10 patients examined. A switch to IgG production was observed in three patients. Morphological examination of E- cells from patients with CLL after treatment with CM demonstrated that these cells were differentiated into plasma-like cells. These results suggest that leukaemic B cells from patients with CLL can be induced to proliferate and differentiate in response to growth and differentiation factors derived by mononuclear leucocytes, in a manner similar to that of normal B cells.