Do saline breast implants harbor microbes?

Recent anecdotal reports have indicated that a high percentage of saline implants harbor dangerous microbes. These reports have caused considerable alarm and fear to saline implant recipients. Reports in the literature of microbial growth in saline implants are infrequent. The expander implant offers an ideal opportunity to study the internal milieu of saline implants in vivo. The study shows that, if used properly, saline implants do not become infected. In this study, 45 expander implants were studied under clinical conditions. No evidence of microbial contamination of the saline was found.

Coping by the carers of dementia sufferers

One hundred and nine of 125 patients from consecutive referrals to a clinical service had an informal carer in contact at least once a week. Thirty-two of the carers had major or minor depression. The active management strategy 'being firm in directing behaviour' was significantly inversely associated with depression amongst carers living with the dementia sufferers, whilst carers who prioritized their daily routines were significantly more likely to be depressed. The active psychological coping strategy 'constructing a larger sense of the illness' was also significantly inversely associated with depression amongst carers living with the patients and 'reduction of expectations' showed a trend in the same direction. There were no significant differences between the coping strategies used by men and women. The type of coping strategy used by carers has an important relationship with depression. Active practical and psychological strategies were of benefit to carers and this has important treatment implications.

T lymphocytes from normal human peritoneum are phenotypically different from their counterparts in peripheral blood and CD3- lymphocyte subsets contain mRNA for the recombination activating gene RAG-1

The surface antigens of peritoneal lymphocytes of healthy human individuals were studied. B lineage cells comprised 2.3% of the total peritoneal lymphocyte population. Although the majority of peritoneal cavity lymphocyte (PCL) T cells expressed alpha beta T cell receptor (TcR), up to 17% expressed gamma delta TcR. The majority of PCL exhibited markers of the thymus-dependent lineage (CD2+ CD3+ TcR alpha beta + CD4+ or CD8 alpha + beta +) and surface antigens associated with memory and activation (CD45RO+ CD11a+ CD18+ CD49d+ HLA-DR). Up to 92% of both CD4+ and CD8+ T cells bore CDw60, thus characterizing the T cell subset containing helper activity for mitogen-driven B cell differentiation. The majority of PCL T cells were CD8+ and, in addition, up to 60% of this population expressed the homodimeric CD8 alpha + beta -. Messenger RNA for the recombination activating gene RAG-1 was examined in CD3- PCL depleted of CD19+ lineage cells. The PCL population which comprised cells containing RAG-1 mRNA transcripts was CD19-, surface IgM-, cytoplasmic IgM- and CD2- CD3- CD4- CD8- CD56-. However, this population was CD7+ (approx. 75%), and contained both CD7- CD34+ (up to 3%) and CD7- CD34+ (up to 3%) cells. These findings are compatible with the hypothesis that the adult human peritoneum provides a microenvironment capable of supporting a thymus-indenpendent differentiation of T lymphocytes.

Stability of standardized patients' performance in a study of clinical decision making

BACKGROUND

Standardized patients (SPs) have been used extensively in teaching, but their reliability for use in research has been infrequently addressed. This study analyzes the reliability of performance of 13 SPs during 228 doctor-patient encounters in a year-long study related to the diagnosis of depression.

METHODS

Patient scenarios were based on real patient cases. Four of the five cases had major depressive disorder. Two to three SPs were coached to enact each of the five case scenarios. Medical encounters were videotaped. Interview content was extracted onto a standardized checklist. Interaction between physician and patient was measured by the Interactional System for Interview Evaluation. Tests of SP performance reliability included the: 1) consistency of symptoms volunteered, 2) stability of affect and behavior, and 3) association of SP performance to detection of depression.

RESULTS

The mean number of SP performances was 20.8 (SD = 5.8), with a range of 6 to 28. Problems with reliability emerged in one of the five patient cases. Results otherwise revealed high intra-performance and inter-performance reliabilities. Detection of depression was consistent across SPs and with the rates reported in the literature.

CONCLUSIONS

This study provides evidence that performances, within and among SPs, remained consistent, even when intervals between performances were as long as 3 months.

Psychosocial interest, medical interviews, and the recognition of depression

OBJECTIVES

To measure primary care physicians' attitudes toward psychosocial issues, determine their relationship to the style of the medical interview, and assess whether attitudes and interview behaviors lead to correct diagnosis in patients with depression.

DESIGN

Physicians were videotaped while interviewing four patients standardized with criteria symptoms of major depression. Physicians were unaware of the mental health focus of the study.

SETTING

Patient examining rooms.

PARTICIPANTS

Physicians were eligible for recruitment if they were board certified or eligible in family practice or internal medicine, practiced primary care medicine, and were listed in regional directories. Standardized patients were recruited from the community.

MAIN OUTCOME MEASURES

Attitudes toward psychosocial issues (measured by the Physician Belief Scale), interview content (measured by review of the videotaped encounters), interview behaviors (measured by the Interaction Analysis System for Interview Evaluation), and a listing of depression in the differential diagnosis (determined by physician debriefing interviews).

RESULTS

Forty-seven community-based practitioners participated. Forty-eight percent of interviews resulted in a diagnosis of depression. Physician Belief Scale scores were not significantly correlated with patient-centered interviewing, psychosocial questions, inquiry about depression symptoms, or a depression diagnosis. Longer interviews were more likely to result in a depression diagnosis.

CONCLUSIONS

High interest in psychosocial issues was not associated with patient-centered interviewing behaviors, questions about psychosocial or depression symptoms, or depression diagnoses. However, certain patient-centered interviewing behaviors, particularly those defined as "affective," did lead to the recognition of depression.

Cystic fibrosis transmembrane conductance regulator mutations that disrupt nucleotide binding

Increasing evidence suggests heterogeneity in the molecular pathogenesis of cystic fibrosis (CF). Mutations such as deletion of phenylalanine at position 508 (delta F508) within the cystic fibrosis transmembrane conductance regulator (CFTR), for example, appear to cause disease by abrogating normal biosynthetic processing, a mechanism which results in retention and degradation of the mutant protein within the endoplasmic reticulum. Other mutations, such as the relatively common glycine-->aspartic acid replacement at CFTR position 551 (G551D) appear to be normally processed, and therefore must cause disease through some other mechanism. Because delta F508 and G551D both occur within a predicted nucleotide binding domain (NBD) of the CFTR, we tested the influence of these mutations on nucleotide binding by the protein. We found that G551D and the corresponding mutation in the CFTR second nucleotide binding domain, G1349D, led to decreased nucleotide binding by CFTR NBDs, while the delta F508 mutation did not alter nucleotide binding. These results implicate defective ATP binding as contributing to the pathogenic mechanism of a relatively common mutation leading to CF, and suggest that structural integrity of a highly conserved region present in over 30 prokaryotic and eukaryotic nucleotide binding domains may be critical for normal nucleotide binding.

Patient presentation, interview content, and the detection of depression by primary care physicians

This study was undertaken in order to better understand the detection of depression by primary care physicians. Specifically, we investigated the relationship between information gathered during the course of the medical interview and the subsequent diagnosis of depression. Forty-seven community-based primary care physicians, unaware of the mental health focus of this research, were videotaped in the office setting, as they interviewed two "typical" standardized patients who met DSM-III-R criteria for major depression. One patient presented with headaches and the other presented with palpitations and chest pain. After each interview, physicians were provided with physical findings and results of any diagnostic procedures they ordered, then asked to construct and explicate their differential diagnoses. The two patients were correctly diagnosed as depressed by 53 and 45% of the physicians. Although detection was related to greater amounts of information gathered, inquiry about the DSM-III-R criteria symptoms was generally low, and in no case was sufficient information acquired to make a formal DSM-III-R diagnosis of depression. However, a subset of the DSM-III-R symptoms (those related to disturbances of appetite, sleep, and other neurovegetative functions) were among the reasons cited for inclusion of depression in the differential, as were psychosocial stressors and the patient's appearance. These findings suggest that detection of depression is low by primary care physicians.

Comparison of perioperative morbidity of anterior cruciate ligament autografts versus allografts

We present a retrospective report of 50 patients (31 autograft and 19 allograft patients) who underwent arthroscopic bone-patellar tendon-bone anterior cruciate ligament (ACL) reconstructions between August 1988 and September 1990. All patients were followed for a minimum of 2 years. The purpose of this study was to analyze each group regarding hospital stay, swelling, thigh atrophy, laxity, strength, endurance, range of motion, patellofemoral symptoms, and complications. We found no statistical difference between autograft or allograft ACL reconstructions with regard to perioperative morbidity.

Modulation of endothelial cell proliferation, adhesion, and motility by recombinant heparin-binding domain and synthetic peptides from the type I repeats of thrombospondin

Thrombospondin is an inhibitor of angiogenesis that modulates endothelial cell adhesion, proliferation, and motility. Synthetic peptides from the second type I repeat of human thrombospondin containing the consensus sequence-Trp-Ser-Pro-Trp- and a recombinant heparin binding fragment from the amino-terminus of thrombospondin mimic several of the activities of the intact protein. The peptides and heparin-binding domain promote endothelial cell adhesion, inhibit endothelial cell chemotaxis to basic fibroblast growth factor (bFGF), and inhibit mitogenesis and proliferation of aortic and corneal endothelial cells. The peptides also inhibit heparin-dependent binding of bFGF to corneal endothelial cells. The antiproliferative activities of the peptides correlate with their ability to bind to heparin and to inhibit bFGF binding to heparin. Peptides containing amino acid substitutions that eliminate heparin-binding do not alter chemotaxis or proliferation of endothelial cells. Inhibition of proliferation by the peptide is time-dependent and reversible. Thus, the antiproliferative activities of the thrombospondin peptide and recombinant heparin-binding domain result at least in part from competition with heparin-dependent growth factors for binding to endothelial cell proteoglycans. These results suggest that both the Trp-Ser-Xaa-Trp sequences in the type I repeats and the amino-terminal domain play roles in the antiproliferative activity of thrombospondin.

Drug interactions in diabetic patients. The risk of losing glycemic control

Any number of prescription and over-the-counter medications, including diuretics and salicylates, can affect glycemic control in diabetic patients. In addition, patients being treated with either insulin or sulfonylurea risk hypoglycemic coma or death if they ingest large quantities of alcohol. The authors of this article discuss the medications most likely to be a problem and provide lists of agents associated with hypoglycemia and hyperglycemia.

Persistence of coronary vasodilator responsivity after cardiac transplantation

Accelerated graft atherosclerosis is a major cause of death after cardiac transplantation. Although its detection currently requires surveillance angiography, loss of vasodilator responsivity may precede obstructive lesions and be detectable by noninvasive assessment of myocardial perfusion. Thirty-five allograft recipients were studied an average of 31 +/- 19 (mean +/- SD) months after transplantation. All were free from angiographically definable macrovascular obstructive coronary artery lesions. Nutritive myocardial perfusion at rest, estimated in absolute terms by positron emission tomography with oxygen-15 water averaged 1.63 +/- 0.51 ml/g/min in patients and was greater than that in 26 healthy volunteers (1.17 +/- 0.33 ml/g/min, p < 0.001). The increase correlated with increased cardiac work at rest in transplant recipients with arterial hypertension and tachycardia. Peak myocardial perfusion induced by intravenous administration of dipyridamole was normal in the transplant recipients (3.49 +/- 1.70 ml/g/min compared with 3.60 +/- 1.41 ml/g/min in volunteers). Because of the high flow at rest, myocardial perfusion reserve (the ratio of hyperemic flow to flow at rest) was diminished (2.3 +/- 1.2 compared with 3.3 +/- 1.5 in volunteers, p < 0.005). These results indicate that the responsivity to vasodilator stimulation is well preserved in transplant recipients devoid of macroscopic coronary arterial lesions obviating detection of early vascular dysfunction in individual subjects. Positron emission tomography may be useful, however, in quantifying the magnitude of the increase in flow at rest secondary to increased cardiac work--a potentially remedial cause of accelerated coronary vascular disease induced by high shear force activation of platelets in the coronary bed, and in detecting impaired perfusion once macrovascular vascular disease is extant.

Effect of nitric oxide production on the redox modulatory site of the NMDA receptor-channel complex

Nitric oxide (NO) is an important messenger both systemically and in the CNS. In digital Ca2+ imaging and patch-clamp experiments, clinically available nitroso compounds that generate NO are shown to inhibit responses mediated by the NMDA subtype of the glutamate receptor on rat cortical neurons in vitro. A mechanism of action for this effect was investigated by using the specific NO-generating agent S-nitrosocysteine. We propose that free sulfhydryl groups on the NMDA receptor-channel complex react to form one or more S-nitrosothiols in the presence of NO. If vicinal thiol groups react in this manner, they can form a disulfide bond(s), which is thought to constitute the redox modulatory site of the receptor, resulting in a relatively persistent blockade of NMDA responses. These reactions with NO can afford protection from NMDA receptor-mediated neurotoxicity. Our results demonstrate a new pathway for NO regulation of physiological function that is not via cGMP, but instead involves reactions with membrane-bound thiol groups on the NMDA receptor-channel complex.

Hypothyroidism in adults with sickle cell anemia

Persons with sickle cell anemia have several indications for transfusion of red blood cells. One of the complications of transfusion of red blood cells is iron overload. Iron overload has been associated with multiple endocrine abnormalities. We report herein three cases of hypothyroidism in adult individuals with sickle cell disease. All three patients were over the age of 45 years at the time of the diagnosis and had received multiple units of transfused red blood cells and had serum ferritin levels of greater than 6,000 ng/mL. All patients were diagnosed during times when they were critically ill. Replacement therapy was instituted in all cases; however, all three patients died shortly after the diagnosis of hypothyroidism was made. Congestive heart failure appeared to be a primary cause of death in all three patients. In the one patient in whom a postmortem examination was done, there was evident extensive fibrosis of the thyroid gland as well as extensive deposition of iron in the cells lining the thyroid follicles. We believe that this represents the first report of clinical hypothyroidism in patients with sickle cell anemia who have received multiple transfusions. Awareness of this condition is especially important given that congestive heart failure is common in sickle cell disease.

Intrinsic anion channel activity of the recombinant first nucleotide binding fold domain of the cystic fibrosis transmembrane regulator protein

The first nucleotide binding fold (NBF-1) from the cystic fibrosis transmembrane regulator (CFTR) has been expressed in bacteria and found to bind ATP and to express anion channel activity when reconstituted onto a planar lipid bilayer. This evidence suggests that the NBF forms the anion-selective portion of the CFTR channel. We also found that the recombinant NBF-1 anion channel is blocked by ATP (1 mM), under which condition it appears to have a minimal conductance of approximately 9 pS and an ohmic current-voltage relationship. We further found that the recombinant NBF-1 bearing the delta F508 mutation has nearly identical anion channel activity to that of the wild-type protein but can be distinguished from wild type under bianionic conditions with chloride and gluconate. We conclude from these data that the anion channel activity of the recombinant NBF-1 could represent all or part of the anion conductance mechanism of CFTR and that the role of the ATP binding by the NBF could be to modulate this anion channel activity.

Recombinant synthesis, purification, and nucleotide binding characteristics of the first nucleotide binding domain of the cystic fibrosis gene product

The majority of mutations which lead to clinical cystic fibrosis are located within the two predicted nucleotide binding domains of the cystic fibrosis gene product. We have used a prokaryotic expression system to synthesize and purify the first nucleotide binding domain (NBD-1, amino acids 426-588) with and without the most common mutation associated with the disease (the deletion of phenylalanine at position 508, delta F508). Both wild type and delta F508 NBD-1 bind ATP-agarose in a quantitatively comparable manner; this binding was inhibited by excess Na2ATP, trinitrophenol-ATP, or 8-azido-ATP. Irreversible NBD-1 labeling by an ATP analog was demonstrated using [32P]8-azido-ATP. This covalent labeling was inhibited by preincubation with Na2ATP, with half-maximal inhibition for Na2ATP occurring at approximately 5 mM for both the wild type and delta F508 nucleotide binding domain. These experiments are among the first to confirm the expectation that the cystic fibrosis transmembrane conductance regulator NBD-1 binds nucleotide. Since, under the conditions used in our study, NBD-1 without phenylalanine 508 displays very similar nucleotide binding characteristics to the wild type protein, our results support previous structural models which predict that the delta F508 mutation should not cause an alteration in ATP binding.

Regulation of tissue plasminogen activator in sickle cell anemia

Evidence of activation of the clotting system in individuals with sickle cell anemia (SCA) has been observed by several investigators. It has been suggested that the clotting and fibrinolytic systems may play a role in the pathophysiology of vaso-occlusion in SCA. We reported previously evidence of abnormal fibrinolytic activity as reflected in decreased releasable tissue plasminogen activator (t-PA) using a functional assay. We have examined the mechanism of the decreased functional releasable t-PA in individuals with SCA. We studied 12 patients with respect to releasable t-PA, fast acting inhibitor to t-PA (or PAI-1), and immunoreactive or antigenic t-PA. These SCA individuals were at their baseline states and not taking medications known to interfere with the fibrinolytic or clotting systems. We found that the mean releasable t-PA for the SCA individuals was 0.01 IU/ml of plasma with a standard error of mean (SEM) of 0.01. The mean releasable t-PA of 118 healthy normal controls was 0.70 IU/ml with SEM 0.10 (P less than .001). The mean level of fast-acting inhibitor to t-PA in unoccluded circulation of the SCA patients' plasma was 16.5 IU/ml with SEM of 3.54. The mean plasma levels of fast-acting inhibitor to t-PA in 56 healthy controls was 2.56 IU/ml with SEM of 0.29 (P less than .0001). The SCA patients had a mean baseline t-PA antigen level of 5.98 ng/ml with SEM of 1.72. The mean level of t-PA antigen of 78 healthy controls using the same technique was 4.3 ng/ml with SEM of 2.7 (not significant). The mean baseline functional t-PA for SCA individuals was 0.15 IU/ml with SEM 0.01 and the mean baseline functional t-PA for 118 controls was 0.17 IU/ml with SEM 0.10. These data suggest that the mechanism of decreased releasable t-PA in sickle cell anemia is related to an elevation of fast-acting inhibitor to t-PA and that antigenically t-PA is present in normal quantities in the baseline plasma in this population.

Force deficit of vascularized skeletal muscle grafts in rabbits

Through autografting experiments on 9-g rectus femoris (RFM) muscles in rabbits, we substantiated a previous observation that the maximum isometric tetanic force (Po) and specific Po (N/cm2) of neurovascular-intact grafts are not different from grafts made with neurovascular repair. We then tested the hypotheses that the specific Po of vascularized grafts is significantly less than that of control RFM muscles and the deficit in the specific Po is associated with increases in connective tissue and interstitial space. The specific Po of the grafts was 65% of the value for control RFM muscles. Connective tissue protein concentration of grafts was 3.8 times greater than the control value of 16.6 +/- 3 micrograms/mg wet mass, but this only accounted for a 5% correction in specific Po. The volume of interstitial space did not differ between grafts and control muscles. We conclude that the deficit of 35% in specific Po of vascularized grafts compared with control values is partially explained by an increase in connective tissue, but a 30% unresolved deficit remains.

Totally implantable intravenous catheters in the management of sickle cell anemia

Totally implantable catheters (TICs) have recently been employed for long-term central venous access in patients with sickle cell disease (SCD). We have reviewed our experience with 10 TICs inserted in patients with SCD. These were compared to 33 TICs inserted in patients without SCD (controls). The primary diagnosis was malignancy in most of the controls. The SCD patients experienced a marked increase in total complications (70 vs. 24%), as well as in complications requiring catheter removal (50 vs. 3%). No variable explained these differences except the presence of SCD. The complications requiring catheter removal from SCD patients were infections, catheter thrombosis, and venous thrombosis. The increased risk of these complications must be considered before a catheter is inserted; however, the average useful life of these catheters exceeded 12 months. They remained useful in the care of patients with poor venous access and multiple complications of SCD.

Failure to detect the presence of pluripotential haemopoietic stem cells in the mouse brain

Single cell suspensions prepared from adult mouse brains were tested for the presence of pluripotential haemopoietic stem cells (colony-forming units, CFU) by transfer into an irradiated recipient and enumeration of the CFU in the recipient's spleen. In contrast to the findings of others (Bartlett, 1982), we did not detect CFU after injection of brain cell suspensions, although they were detectable after inoculation with bone marrow cells. The number of CFU in recipients after transfer of increasing numbers of brain cells was the same as that detected in the irradiated controls which had not received any transferred cells. Finally, cells from the brain, in contrast to bone marrow cells, were not able to protect recipient animals from the effects of lethal irradiation.

Comparison of formal language therapy with supportive counseling for aphasia due to acute vascular accident

A total of 60 right-handed patients with acute aphasia due to left hemispheral stroke were randomly assigned to two modes of therapy for six months, beginning one month after the ictus. Conventional speech therapy provided by professional speech pathologists twice weekly was compared with emotionally supportive counseling therapy, also provided by professional speech pathologists at the same intervals. Language function was tested periodically by the Porch Index of Communicative Ability. Fifty of the subjects were also tested at ten months after the ictus. There was no difference in the amount of improvement between the two groups.