Synthetic peptides which inhibit the interaction between C1q and immunoglobulin and prolong xenograft survival

BACKGROUND

Acute vascular xenograft rejection (AVXR), also termed delayed xenograft rejection (DXR), occurs when hyperacute rejection (HAR) is prevented by strategies directed at xenoreactive natural antibodies and/or complement activation. We have hypothesized that AVXR/DXR is initiated in part by early components of the complement cascade, notably C1q. We have developed synthetic peptides (termed CBP2 and WY) that interfere with the interaction between C1q and antibody.

METHODS

CBP2 and the WY-conjugates were used as inhibitors of immunoglobulin aggregate binding to solid phase C1q. Inhibition of complement activation by the peptides of the classical system was determined using lysis assays with sensitized sheep red blood cells or porcine aortic endothelial cells as targets and of the alternate complement pathway using guinea pig red blood cells as targets. Two transplant models were used to study the effects of administering peptides to recipients: rat heart transplant to presensitized mouse, and guinea heart transplant to PVG C6-deficient rats.

RESULTS

CBP2 and WY-conjugates inhibited immunoglobulin aggregate binding to C1q. The peptides also inhibited human complement-mediated lysis of sensitized sheep red blood cells and porcine aortic endothelial cells in a dose-dependent manner and the WY-conjugates prevented activation of the alternate complement pathway as shown by inhibition of guinea pig red blood cells lysis with human serum. In addition, the use of the peptides and conjugates resulted in significant prolongation of xenograft survival.

CONCLUSIONS

The CBP2 and WY peptides exhibit the functional activity of inhibition of complement activation. These peptides also prolong xenograft survival and thus provide reagents for the study of the importance of C1q and other complement components in transplant rejection mechanisms.

Cervical cytology history in Irish doctors and midwives

In Ireland we do not have a national cervical screening programme. It is hoped that such a service will soon be implemented and a pilot programme is currently underway. In our department there was a perception that many women working in the area of women's health had a "laissez-faire" attitude towards their own cervical cytology. This prompted us to perform an anonymous survey of a sample of Irish gynaecologists, general practitioners and midwives in advance of a national cervical screening programme. Overall, 80% of the questionnaires were returned completed--72% from gynaecologists, 68% from GPs and 100% from midwives. 60% of those who returned completed questionnaires were "up-to-date", 21% were "late" and 19% had never had a cervical smear.

Are seminal fluid microorganisms of significance or merely contaminants?

OBJECTIVE

To determine the contribution of urethral and skin flora to seminal fluid cultures and the relation between bacteriospermia and seminal leukocytes.

DESIGN

Prospective study.

SETTING

IVF-ET unit at a university teaching hospital.

PATIENT(S)

Sixty men starting an IVF-ET program.

INTERVENTION(S)

Culture of sequential first-catch urine, midstream urine, and semen samples with evaluation of seminal leukocytes.

MAIN OUTCOME MEASURE(S)

A comparison of microbes from first-catch urine, midstream urine, and semen samples and the correlations of seminal microbes, elevated leukocyte concentrations, and pregnancy.

RESULT(S)

Microorganisms were detected in 37% of first-catch urine samples, 27% of midstream urine samples, and 51% of semen samples. Most microorganisms were gram-positive microbes and were common to both urine and semen samples. Mean and median leukocyte concentrations were 0.98 x 10(6)/mL and 0.10 x 10(6)/mL, respectively. There was no correlation between seminal microbes and raised leukocytes or between leukocytospermia and/or bacteriospermia and pregnancy.

CONCLUSION(S)

Microorganisms are commonly found in insignificant quantities in the semen of asymptomatic men. The frequent isolation of gram-positive microbes common to both urine and semen and the absence of a correlation with raised leukocyte concentrations suggest that bacteriospermia most commonly represents contamination.

Designing an ambulatory clinical practice for outcomes improvement: from vision to reality--the Spine Center at Dartmouth-Hitchcock, year one

Development of a new program for diagnosis and treatment of spine-related problems provided a unique opportunity to design and implement a new model for delivery of health care incorporating outcomes measurement and improvement. Key features include: application of microsystem thinking and interdisciplinary practice; integration of a uniform outcomes measurement tool, the Dartmouth Clinical Value Compass; and touch pad technology for data collection. This, for the first time, provided clinically meaningful point-of-service data and aggregated information for improvement. A further advantage was the ability to integrate a clinical research program within this microsystem. A multisite clinical research trial, the Spine Patient Outcomes Research Trial (SPORT), modeled on the Spine Center microsystem and funded by The National Institute of Arthritis, Musculoskeletal and Skin Diseases and the Office of Research on Woman's Health, the National Institutes of Health, and the National Institute of Occupational Safety and Health, the Centers for Disease Control and Prevention, is currently underway. The significant problems we face today cannot be solved by the same level of thinking that created them.

A multicenter comparison of cognitive-behavioral therapy and interpersonal psychotherapy for bulimia nervosa

BACKGROUND

Research suggests that cognitive-behavioral therapy (CBT) is the most effective psychotherapeutic treatment for bulimia nervosa. One exception was a study that suggested that interpersonal psychotherapy (IPT) might be as effective as CBT, although slower to achieve its effects. The present study is designed to repeat this important comparison.

METHOD

Two hundred twenty patients meeting DSM-III-R criteria for bulimia nervosa were allocated at random to 19 sessions of either CBT or IPT conducted over a 20-week period and evaluated for 1 year after treatment in a multisite study.

RESULTS

Cognitive-behavioral therapy was significantly superior to IPT at the end of treatment in the percentage of participants recovered (29% [n=32] vs 6% [n=71), the percentage remitted (48% [n=53] vs 28% [n = 31]), and the percentage meeting community norms for eating attitudes and behaviors (41% [n=45] vs 27% [n=30]). For treatment completers, the percentage recovered was 45% (n= 29) for CBT and 8% (n= 5) for IPT. However, at follow-up, there were no significant differences between the 2 treatments: 26 (40%) CBT completers had recovered at follow-up compared with 17 (27%) IPT completers.

CONCLUSIONS

Cognitive-behavioral therapy was significantly more rapid in engendering improvement in patients with bulimia nervosa than IPT. This suggests that CBT should be considered the preferred psychotherapeutic treatment for bulimia nervosa.

The Aeromonas metallo-beta-lactamases: genetics, enzymology, and contribution to drug resistance

Aeromonads are environmental microorganisms that can be responsible for both human and animal infections. Individual Aeromonas strains can produce up to three different, inducible, chromosomally encoded beta-lactamases, including a group 1 molecular class C cephalosporinase, a group 2d molecular class D penicillinase, and a group 3 molecular class B metallo-beta-lactamase, which contribute to beta-lactam resistance in members of this genus. Among these enzymes, the metallo-beta-lactamases are clinically relevant because of their ability to hydrolyze carbapenem antibiotics, and also represent a relevant investigational model for studying molecular class B beta-lactamases because of their unique enzymological behavior. An overview on the distribution, genetics, and enzymology of these enzymes is reported, and the contribution of these enzymes to microbial drug resistance is also discussed.

Comparative evaluation of three Tactylon(TM) condoms and a latex condom during vaginal intercourse: breakage and slippage

This study compared breakage and slippage rates of three male condom styles made of Tactylon(TM), a synthetic elastomer, to those of a marketed latex condom during vaginal intercourse. Safety and acceptability outcomes were also assessed. This two-center, prospective, crossover study enrolled 443 couples. Each couple was randomly assigned to use three condoms of each type in one of 24 use sequences. Couples completed questionnaires after using each condom, all of one condom type, and all four condom types. The percentage and standard error (SE, in parentheses) of latex condoms with clinical breakage was 0.86% (0.295). Percentages for Tactylon condoms were not equivalent to the latex study condom, ranging from 3.50% to 4.17%. The percentage and SE of latex condoms with complete slippage was 1.11% (0.328). Percentages for Tactylon condoms were equivalent to those for latex, ranging from 0.70% to 1.31%. The Low-Modulus Tactylon condom was the most preferred. Fewer medical events were reported with the Tactylon condoms than with the latex condom. It was concluded that Tactylon condoms were equivalent to the latex condom in terms of slippage but not breakage. However, safety and acceptability seemed to be better for Tactylon condoms. This may improve consistency of use and may attract new users.

Microsatellite alterations plasma DNA of primary breast cancer patients

The aim of this study was to analyze plasma DNA from primary and metastatic breast cancer cases for tumor-specific alterations and to compare these findings with immunocytochemistry and estimation of cytokeratin 19 (CK19) mRNA for detection of micrometastases. DNA was extracted from plasma, lymphocytes, and microdissected tumor tissue sections obtained from 71 patients with breast cancer and 9 controls. DNA samples were analyzed for loss of heterozygosity (LOH) and/or microsatellite instability (MI) by PCR with two polymorphic markers (DM-1 and D16S400). Reverse transcription-quantitative PCR (QPCR) and immunocytochemistry were used for detection of CK19 mRNA and protein. Breast cancer plasma DNA displayed frequent LOH (31.3%) and MI (11.6%) supported by the same alteration in microdissected tumor DNA. Most notably, 10 of the 39 patients with primary breast cancer showed LOH (n = 6) or MI (n = 4). We compared plasma tumor DNA, plasma and bone marrow QPCR, and blood and bone marrow immunocytochemistry in 32 of the patients with primary cancer. Of these, only one patient had immunocytochemically detectable carcinoma cells in the blood, and three showed abnormally high levels of plasma CK19 mRNA. All four of these patients had plasma DNA alterations. We then compared bone marrow findings: of the 10 primary breast cancers that showed LOH or MI, 6 had elevated CK19 mRNA and 5 had immunocytochemically positive cells. Tumor DNA is readily detectable in plasma of primary and metastatic breast cancer patients, and plasma DNA alterations (LOH and MI) reflect those seen in the tumor. The application of microsatellite analyses to plasma DNA may be useful in assessing tumor burden in breast cancer patients, particularly when combined with QPCR, and is preferable for patients with breast cancer, for whom sequential bone marrow aspiration is undesirable.

Failure rates among perfect users and during perfect use: a distinction that matters

To make an informed decision when choosing a contraceptive, women and couples need to know how effective different methods are when used perfectly, where perfect use is defined as following the directions for use. In this article, we show that unbiased estimates of pregnancy rates during perfect use can be guaranteed only if information on consistency and correctness of use is available for each menstrual cycle. The estimated probability of pregnancy during a year of perfect use among the subset of women who always used a method perfectly will be biased upward.

Amiodarone for resuscitation after out-of-hospital cardiac arrest due to ventricular fibrillation

BACKGROUND

Whether antiarrhythmic drugs improve the rate of successful resuscitation after out-of-hospital cardiac arrest has not been determined in randomized clinical trials.

METHODS

We conducted a randomized, double-blind, placebo-controlled study of intravenous amiodarone in patients with out-of-hospital cardiac arrest. Patients who had cardiac arrest with ventricular fibrillation (or pulseless ventricular tachycardia) and who had not been resuscitated after receiving three or more precordial shocks were randomly assigned to receive 300 mg of intravenous amiodarone (246 patients) or placebo (258 patients).

RESULTS

The treatment groups had similar clinical profiles. There was no significant difference between the amiodarone and placebo groups in the duration of the resuscitation attempt (42+/-16.4 and 43+/-16.3 minutes, respectively), the number of shocks delivered (4+/-3 and 6+/-5), or the proportion of patients who required additional antiarrhythmic drugs after the administration of the study drug (66 percent and 73 percent). More patients in the amiodarone group than in the placebo group had hypotension (59 percent vs. 48 percent, P=0.04) or bradycardia (41 percent vs. 25 percent, P=0.004) after receiving the study drug. Recipients of amiodarone were more likely to survive to be admitted to the hospital (44 percent, vs. 34 percent of the placebo group; P=0.03). The benefit of amiodarone was consistent among all subgroups and at all times of drug administration. The adjusted odds ratio for survival to admission to the hospital in the amiodarone group as compared with the placebo group was 1.6 (95 percent confidence interval, 1.1 to 2.4; P=0.02). The trial did not have sufficient statistical power to detect differences in survival to hospital discharge, which differed only slightly between the two groups.

CONCLUSIONS

In patients with out-of-hospital cardiac arrest due to refractory ventricular arrhythmias, treatment with amiodarone resulted in a higher rate of survival to hospital admission. Whether this benefit extends to survival to discharge from the hospital merits further investigation.

A double-blind comparison of empirical oral and intravenous antibiotic therapy for low-risk febrile patients with neutropenia during cancer chemotherapy

BACKGROUND

Among patients with fever and neutropenia during chemotherapy for cancer who have a low risk of complications, oral administration of empirical broad-spectrum antibiotics may be an acceptable alternative to intravenous treatment.

METHODS

We conducted a randomized, double-blind, placebo-controlled study of patients (age, 5 to 74 years) who had fever and neutropenia during chemotherapy for cancer. Neutropenia was expected to be present for no more than 10 days in these patients, and they had to have no other underlying conditions. Patients were assigned to receive either oral ciprofloxacin plus amoxicillin-clavulanate or intravenous ceftazidime. They were hospitalized until fever and neutropenia resolved.

RESULTS

A total of 116 episodes were included in each group (84 patients in the oral-therapy group and 79 patients in the intravenous-therapy group). The mean neutrophil counts at admission were 81 per cubic millimeter and 84 per cubic millimeter, respectively; the mean duration of neutropenia was 3.4 and 3.8 days, respectively. Treatment was successful without the need for modifications in 71 percent of episodes in the oral-therapy group and 67 percent of episodes in the intravenous-therapy group (difference between groups, 3 percent; 95 percent confidence interval, -8 percent to 15 percent; P=0.48). Treatment was considered to have failed because of the need for modifications in the regimen in 13 percent and 32 percent of episodes, respectively (P<0.001) and because of the patient's inability to tolerate the regimen in 16 percent and 1 percent of episodes, respectively (P<0.001). There were no deaths. The incidence of intolerance of the oral antibiotics was 16 percent, as compared with 8 percent for placebo (P=0.07).

CONCLUSIONS

In hospitalized low-risk patients who have fever and neutropenia during cancer chemotherapy, empirical therapy with oral ciprofloxacin and amoxicillin-clavulanate is safe and effective.

Micrometastases in esophagogastric cancer: high detection rate in resected rib segments

BACKGROUND & AIMS

Micrometastases within bone marrow indicate a poor prognosis. We prospectively examined micrometastases in patients undergoing resection of esophagogastric cancers for (1) prevalence in rib marrow; (2) comparative detection rates in rib and iliac crest marrow; (3) responsiveness to neoadjuvant therapy; and (4) viability and tumorigenicity.

METHODS

In 50 consecutive patients, marrow was obtained before manipulation of the primary tumor. Micrometastatic cells were detected by staining contaminant cytokeratin-18-positive cells. Viability and tumorigenicity were determined by culture and xenograft.

RESULTS

Micrometastases were detected in rib marrow from 88% of patients (44 of 50). When bilateral iliac crest marrow was also obtained, micrometastases were found in 15% (4 of 27) compared with 89% (24 of 27) for ribs (P < 0.001). Detection rates were independent of histological type or nodal status and were similar in patients with and without neoadjuvant therapy. Metastatic cells were cultured from rib marrow of 5 of 7 patients and were tumorigenic in nude mice.

CONCLUSIONS

Most patients undergoing resection of esophagogastric malignancies have micrometastases in rib marrow. Detection rates based on iliac crest marrow are underestimates. Hematogenous spread of metastatic cells is independent of histological type or nodal status. The metastatic cells are viable, tumorigenic, and resistant to neoadjuvant therapy.

PCR bias toward the wild-type k-ras and p53 sequences: implications for PCR detection of mutations and cancer diagnosis

PCR-based cancer diagnosis requires detection of rare mutations in k-ras, p53 or other genes. The assumption has been that mutant and wild-type sequences amplify with near equal efficiency, so that they are eventually present in proportions representative of the starting material. Work on factor IX suggests that this assumption is invalid for one case of near-sequence identity. To test the generality of this phenomenon and its relevance to cancer diagnosis, primers distant from point mutations in p53 and k-ras were used to amplify wild-type and mutant sequences from these genes. A substantial bias against PCR amplification of mutants was observed for two regions of the p53 gene and one region of k-ras. For k-ras and p53, bias was observed when the wild-type and mutant sequences were amplified separately or when mixed in equal proportions before PCR. Bias was present with proofreading and non-proofreading polymerases. Mutant and wild-type segments of the factor V, cystic fibrosis transmembrane conductance regulator and prothrombin genes were amplified and did not exhibit PCR bias. Therefore, the assumption of equal PCR efficiency for point mutant and wild-type sequences is invalid in several systems. Quantitative or diagnostic PCR will require validation for each locus, and enrichment strategies may be needed to optimize detection of mutants.

The influence of basal nitric oxide activity on pulmonary vascular resistance in patients with congestive heart failure

Increased pulmonary resistance may reduce survival and treatment options in patients with congestive heart failure. Nitric oxide (NO) is a determinant of normal pulmonary resistance vessel tone. We tested the hypothesis that loss of NO function contributes to increased pulmonary vascular resistance index (PVRI) in congestive heart failure. Pulmonary arterial resistance vessel function was studied in 25 conscious adults. Three groups were studied: 8 controls, 9 patients with congestive heart failure and normal PVRI, and 8 patients with congestive heart failure and raised PVRI. Segmental arterial flow was determined with a Doppler wire and quantitative angiography. NG-monomethyl-L-arginine (L-NMMA) was used to inhibit NO, whereas phenylephrine was used as an endothelium-independent control. The response to inhibition of NO with L-NMMA was less in patients with congestive heart failure and elevated PVRI than in patients with congestive heart failure and normal PVRI (p <0.05). The difference in response between the congestive heart failure groups was specific to NO-dependent regulation because the response to the endothelium-independent constrictor phenylephrine was not different (p = 0.92). There was no difference in response to L-NMMA between controls and patients with congestive heart failure and normal PVRI. The response to L-NMMA correlated to PVRI. In adults with congestive heart failure, NO appears to play an important role in maintaining normal pulmonary resistance.

Microsatellite instability in ductal carcinoma in situ of the breast

Microsatellite instability (MI+) is associated with defects in mismatch repair, resulting in a 'mutator' phenotype and the development and progression of cancer. MI+ has been documented in invasive breast carcinomas. This study was undertaken to determine whether MI+ is found in the early non-invasive form of breast cancer, ductal carcinoma in situ (DCIS). We examined microdissected ducts from 23 cases of DCIS with 11 markers comprising mono-, di-, and trinucleotide repeats from six chromosomal regions. Five tumours (22 per cent) displayed MI+ at two or more loci, in all ducts examined. A further seven (30 per cent) tumours showed alterations at a single locus (the DM-1 trinucleotide), and for two of these, heterogeneity between ducts was observed. Alterations at microsatellite repeat motifs in the coding regions of four cancer-associated genes (TGF beta RII, IGFIIR, BAX, and E2F-4) were not observed. Immunohistochemistry revealed that there was no loss of reactivity for the mismatch repair proteins, MLH1, MSH2, and PMS2, in the DCIS cases. In general, MI+ tumours and those with alterations at the DM-1 microsatellite were predominantly of higher nuclear grade and expressing c-erbB-2, suggesting that aberrations in DNA repair functions may lead to the acquisition of a more aggressive phenotype in breast cancer.

Randomised controlled trial of prophylactic antibiotics before insertion of intrauterine devices. IUD Study Group

BACKGROUND

The value of antibiotic prophylaxis before insertion of an intrauterine device (IUD) remains uncertain. We undertook a triple-masked, randomised, placebo-controlled trial to find out whether such prophylaxis reduces the rate of IUD removal within 90 days.

METHODS

11 clinic sites in southern California enrolled women who requested IUD insertion and were at low risk of sexually transmitted infection according to self-reported medical history. We randomly assigned 1985 participants either 500 mg azithromycin or placebo capsules of identical appearance taken about 1 h before insertion of a Copper T 380A IUD. 118 women did not have an IUD inserted. We followed up 1833 of the remaining 1867 (98%) participants for at least 90 days after insertion.

FINDINGS

The rate of IUD removal for any reason other than partial expulsion was 3.8% (35/918) in the antibiotic group and 3.4% (31/915) in the placebo group (relative risk 1.1 [95% CI 0.7-1.8]). The two treatment groups sought medical attention with equal frequency (mean 38 visits per 100 women). During the 90 days after IUD insertion, only one woman from each assignment group had salpingitis, as defined by established criteria.

INTERPRETATION

Prophylaxis with azithromycin did not affect the likelihood that a woman would retain her IUD at 90 days or the frequency of postinsertion medical attention. In appropriately screened women, the risk of upper-genital-tract infection is negligible after IUD insertion, with or without the administration of prophylactic antibiotics.

Molecular pathology of breast cancer and its application to clinical management

Breast cancer is a major cause of morbidity and mortality in women in many parts of the world. Breast carcinomas are heterogenous in their biological and clinical behaviour and a greater understanding of how they develop and progress could lead to more directed forms of screening and therapy. It is important to determine the molecular mechanisms underlying the natural history of breast cancer. Developments in the techniques for molecular analysis have meant that they can now be applied to a large range of clinical material such as cytological preparations and fixed, embedded material, so increasing the potential for relating any molecular alterations to clinical behaviour and response to therapy. In this review we consider recent developments in three areas of importance to breast cancer; genetic analysis-oncogenes, tumour suppressor genes, loss of heterozygosity, microsatellite instability, familial breast cancer; steroid receptors, oestrogen regulated proteins, epidermal growth factor receptor, growth factors particularly transforming growth factor beta; and cell adhesion, invasion and metastasis-E-cadherin, integrins, proteases. These are discussed in relation to potential for screening, prognosis and treatment.

Loss of heterozygosity at the mannose 6-phosphate insulin-like growth factor 2 receptor gene correlates with poor differentiation in early breast carcinomas

Chromosome 6q has been shown to be one of the most frequent sites for allelic loss in human breast cancer. The mannose 6-phosphate/insulin-like growth factor 2 receptor (IGF2R) gene, which maps to chromosome 6q26-27, functions in the activation of TGF-beta1, a potent growth inhibitor for most cell types, the degradation of the mitogen IGF2 and the intracellular trafficking of lysosomal enzymes. Loss of heterozygosity (LOH) at the IGF2R locus with mutations in the remaining allele have been reported in liver cancers and recently in two high-grade cases of ductal carcinoma in situ of the breast. We have sought to confirm that allelic loss of IGF2R is an early event in the aetiology of breast cancer by screening a group of 'early' lesions for LOH at a polymorphic microsatellite marker within the IGF2R gene using polymerase chain reaction (PCR). Several microdissected tumour foci were analysed for each of 40 mammographically detected invasive carcinomas and 22 cases of pure ductal carcinoma in situ (DCIS). None of 25 (62.5%) informative early invasive carcinomas showed any evidence of LOH. This group comprised predominantly of well- to moderately differentiated cases (95%). However, 4 out of 18 informative DCIS cases (22%) showed clear evidence of LOH. Three of these were poorly differentiated (high-grade) lesions. These data suggest that loss of heterozygosity at the IGF2R gene is associated with poor differentiation at this early stage of breast cancer development and progression.

Loss of heterozygosity at chromosome 6q in preinvasive and early invasive breast carcinomas

We have used polymerase chain reaction (PCR) analysis to study the incidence of allelic imbalance at four polymorphic microsatellite markers on chromosome 6q25.1-27, three dinucleotide repeats and one trinucleotide repeat, for microdissected tumour foci from a group of 75 'early' breast carcinomas. The tumours comprised 16 preinvasive cases of ductal carcinoma in situ (DCIS) and 59 mammographically detected early invasive carcinomas. Loss of heterozygosity (LOH) was detected at all four loci and in all types and grade of disease. The frequency of LOH ranged from 23% to 50% depending on the marker studied. The highest frequency of LOH was observed at the D6S186 locus for the cases of DCIS and at the oestrogen receptor locus for the invasive carcinomas. These data suggest that the inactivation of tumour-suppressor genes within this region on chromosome 6q is important for the development of these early lesions.