The Transatlantic Recommendations for Prostate Gland Evaluation with Magnetic Resonance Imaging After Focal Therapy (TARGET): A Systematic Review and International Consensus Recommendations

BACKGROUND AND OBJECTIVE

Magnetic resonance imaging (MRI) can detect recurrences after focal therapy for prostate cancer but there is no robust guidance regarding its use. Our objective was to produce consensus recommendations on MRI acquisition, interpretation, and reporting after focal therapy.

METHODS

A systematic review was performed in July 2022 to develop consensus statements. A two-round consensus exercise was then performed, with a consensus meeting in January 2023, during which 329 statements were scored by 23 panellists from Europe and North America spanning urology, radiology, and pathology with experience across eight focal therapy modalities. Using RAND Corporation/University of California-Los Angeles methodology, the Transatlantic Recommendations for Prostate Gland Evaluation with MRI after Focal Therapy (TARGET) were based on consensus for statements scored with agreement or disagreement.

KEY FINDINGS AND LIMITATIONS

In total, 73 studies were included in the review. All 20 studies (100%) reporting suspicious imaging features cited focal contrast enhancement as suspicious for cancer recurrence. Of 31 studies reporting MRI assessment criteria, the Prostate Imaging-Reporting and Data System (PI-RADS) score was the scheme used most often (20 studies; 65%), followed by a 5-point Likert score (six studies; 19%). For the consensus exercise, consensus for statements scored with agreement or disagreement increased from 227 of 295 statements (76.9%) in round one to 270 of 329 statements (82.1%) in round two. Key recommendations include performing routine MRI at 12 mo using a multiparametric protocol compliant with PI-RADS version 2.1 standards. PI-RADS category scores for assessing recurrence within the ablation zone should be avoided. An alternative 5-point scoring system is presented that includes a major dynamic contrast enhancement (DCE) sequence and joint minor diffusion-weighted imaging and T2-weighted sequences. For the DCE sequence, focal nodular strong early enhancement was the most suspicious imaging finding. A structured minimum reporting data set and minimum reporting standards for studies detailing MRI data after focal therapy are presented.

CONCLUSIONS AND CLINICAL IMPLICATIONS

The TARGET consensus recommendations may improve MRI acquisition, interpretation, and reporting after focal therapy for prostate cancer and provide minimum standards for study reporting.

PATIENT SUMMARY

Magnetic resonance imaging (MRI) scans can detect recurrent of prostate cancer after focal treatments, but there is a lack of guidance on MRI use for this purpose. We report new expert recommendations that may improve practice.

Evaluation of Outcomes Following Focal Ablative Therapy for Treatment of Localized Clinically Significant Prostate Cancer in Patients >70 Years: A Multi-institute, Multi-energy 15-Year Experience

PURPOSE

In older patients who do not wish to undergo watchful waiting, focal therapy could be an alternative to the more morbid radical treatment. We evaluated the role of focal therapy in patients 70 years and older as an alternative management modality.

MATERIALS AND METHODS

A total of 649 patients across 11 UK sites receiving focal high-intensity focused ultrasound or cryotherapy between June 2006 and July 2020 reported within the UK-based HEAT (HIFU Evaluation and Assessment of Treatment) and ICE (International Cryotherapy Evaluation) registries were evaluated. Primary outcome was failure-free survival, defined by need for more than 1 focal reablation, progression to radical treatment, development of metastases, need for systemic treatment, or prostate cancer-specific death. This was compared to the failure-free survival in patients undergoing radical treatment via a propensity score weighted analysis.

RESULTS

Median age was 74 years (IQR: 72, 77) and median follow-up 24 months (IQR: 12, 41). Sixty percent had intermediate-risk disease and 35% high-risk disease. A total of 113 patients (17%) required further treatment. Sixteen had radical treatment and 44 required systemic treatment. Failure-free survival was 82% (95% CI: 76%-87%) at 5 years. Comparing patients who had radical therapy to those who had focal therapy, 5-year failure-free survival was 96% (95% CI: 93%-100%) and 82% (95% CI: 75%-91%) respectively (P < .001). Ninety-three percent of those in the radical treatment arm had received radiotherapy as their primary treatment with its associated use of androgen deprivation therapy, thereby leading to potential overestimation of treatment success in the radical treatment arm, especially given the similar metastases-free and overall survival rates seen.

CONCLUSIONS

We propose focal therapy to be an effective management option for the older or comorbid patient who is unsuitable for or not willing to undergo radical treatment.

Examining the experiences of pediatric mental health care providers during the early stage of the COVID-19 pandemic

BACKGROUND

The COVID-19 pandemic fundamentally impacted the way that mental health services were provided. In order to prevent the spread of infection, many new public health precautions, including mandated use of masks, quarantine and isolation, and closures of many in-person activities, were implemented. Public health mandates made it necessary for mental health services to immediately shift their mode of delivery, creating increased confusion and stress for mental health providers. The objective of this study is to understand the impact of pandemics on the clinical and personal lives of mental health providers working with children during the early months of the COVID-19 pandemic, March -June 2020.

METHODS

Mental health providers (n = 98) were recruited using purposive sampling from a public health service in Canada. Using qualitative methods, semi-structured focus groups were conducted to understand the experiences of mental health service providers during the beginning of the COVID-19 pandemic.

RESULTS

Data from the focus groups were analysed and three main themes emerged: (1) shift to virtual delivery and working from home; (2) concerns about working in person; (3) exhaustion and stress from working through the pandemic.

DISCUSSION

This study gave voice to mental health providers as they provided continuity of care throughout the uncertain early months of the pandemic. The results provide insight into the impact times of crisis have on mental health providers, as well as provide practical considerations for the future in terms of supervision and feedback mechanisms to validate experiences.

Focal therapy versus radical prostatectomy and external beam radiotherapy as primary treatment options for non-metastatic prostate cancer: results of a cost-effectiveness analysis

AIMS

Focal therapy treats individual areas of tumour in non-metastatic prostate cancer in patients unsuitable for active surveillance. The aim of this work was to evaluate the cost-effectiveness of focal therapy versus prostatectomy and external beam radiotherapy (EBRT).

MATERIALS AND METHODS

A Markov cohort health state transition model with four health states (stable disease, local recurrence, metastatic disease and death) was created, evaluating costs and utilities over a 10-year time horizon for patients diagnosed with non-metastatic prostate cancer. National Health Service (NHS) for England perspective was used, based on direct healthcare costs. Clinical transition probabilities were derived from prostate cancer registries in patients undergoing radical prostatectomy, EBRT and focal therapy using cryotherapy (Boston Scientific) or high-intensity focused ultrasound (HIFU) (Sonablate). Propensity score matching was used to ensure that at-risk populations were comparable. Variables included age, prostate-specific antigen (PSA), International Society of Urological Pathology (ISUP) grade group, maximum cancer core length (mm), T-stage and year of treatment.

RESULTS

Focal therapy was associated with a lower overall cost and higher quality-adjusted life year (QALY) gains than either prostatectomy or EBRT, dominating both treatment strategies. Positive incremental net monetary benefit (NMB) values confirm focal therapy as cost-effective versus the alternatives at a willingness to pay (WTP) threshold of £30,000/QALY. One-way deterministic sensitivity analyses revealed consistent results.

LIMITATIONS

Data used to calculate the transition probabilities were derived from a limited number of hospitals meaning that other potential treatment options were excluded. Limited data were available on later outcomes and none on quality of life data, therefore, literature-based estimates were used.

CONCLUSIONS

Cost-effectiveness modelling demonstrates use of focal therapy (cryotherapy or HIFU) is associated with greater QALY gains at a lower overall cost than either radical prostatectomy or EBRT, representing good value for money in the NHS.

Les effets de la pandémie de COVID-19 sur la santé mentale des enfants atteints de problèmes de santé physique ou d’incapacités, des familles et des professionnels de la santé

Objectifs

La pandémie de COVID-19 a influé sur la santé mentale de la population. Les familles des enfants qui ont des vulnérabilités en matière de santé ont été démesurément touchées par les politiques liées à la pandémie et les perturbations aux services, car elles s’appuient beaucoup sur le système de soins de santé et de services sociaux. Les chercheurs ont établi les répercussions de la pandémie de COVID-19 sur les enfants ayant des vulnérabilités en matière de santé physique et des incapacités, les familles et les professionnels de la santé.

Méthodologie

Des enfants ayant diverses vulnérabilités en matière de santé (transplantation cardiaque, affections respiratoires, anémie falciforme, trouble du spectre de l’autisme, troubles de santé mentale et approche de la fin de vie en raison d’une série de causes sous-jacentes), leurs parents et leurs professionnels de la santé ont participé à des entrevues semi-structurées. Les chercheurs ont utilisé des méthodes d’analyse qualitative et en ont extrait les thèmes liés aux effets et les recommandations en vue d’améliorer la pratique.

Résultats

Au total, 262 participants (30 enfants, 76 parents, 156 professionnels de la santé) ont été interviewés. Les enfants ont décrit leur solitude et leur isolement, les parents, leur épuisement, et les professionnels de la santé, la pression ressentie et un sentiment de détresse morale. Les thèmes reflétaient les effets de la pandémie sur la santé mentale des enfants, des familles et des professionnels de la santé, de même que les ressources insuffisantes pour soutenir la santé mentale, les influences organisationnelles et politiques qui ont façonné la prestation des services et les recommandations pour améliorer la prestation de ces services.

Conclusion

Les restrictions sanitaires imposées par la pandémie et les modifications aux soins ont eu de profondes répercussions sur la santé mentale des enfants qui ont des vulnérabilités en matière de santé, les familles et les professionnels de la santé. Les recommandations incluent la rédaction et l’adoption d’information ciblée sur la pandémie et la mise en œuvre de services de soutien en santé mentale. Ces résultats amplifient la nécessité de renforcer les capacités, y compris des stratégies proactives et la planification de mesures d’atténuation du risque dans l’éventualité d’une future pandémie.

Mental health impacts of the COVID-19 pandemic on children with underlying health and disability issues, and their families and health care providers

Objectives

The COVID-19 pandemic has impacted mental health at a population level. Families of children with health vulnerabilities have been disproportionately affected by pandemic-related policies and service disruptions as they substantially rely on the health and social care system. We elicited the impact of the COVID-19 pandemic on children with health and disability-related vulnerabilities, their families, and their health care providers (HCPs).

Methods

Children with diverse health vulnerabilities (cardiac transplantation, respiratory conditions, sickle cell disease, autism spectrum disorder, mental health issues, and nearing the end of life due to a range of underlying causes), as well as their parents and HCPs, participated in semi-structured interviews. Data were analyzed using qualitative content analysis in determining themes related to impact and recommendations for practice improvement.

Results

A total of 262 participants (30 children, 76 parents, 156 HCPs) were interviewed. Children described loneliness and isolation; parents described feeling burnt out; and HCPs described strain and a sense of moral distress. Themes reflected mental health impacts on children, families, and HCPs, with insufficient resources to support mental health; organizational and policy influences that shaped service delivery; and recommendations to enhance service delivery.

Conclusion

Children with health vulnerabilities, their families and HCPs incurred profound mental health impacts due to pandemic-imposed public health restrictions and care shifts. Recommendations include the development and application of targeted pandemic information and mental health supports. These findings amplify the need for capacity building, including proactive strategies and mitigative planning in the event of a future pandemic.

Likert vs PI-RADS v2: a comparison of two radiological scoring systems for detection of clinically significant prostate cancer

OBJECTIVE

To compare the clinical validity and utility of Likert assessment and the Prostate Imaging Reporting and Data System (PI-RADS) v2 in the detection of clinically significant and insignificant prostate cancer.

PATIENTS AND METHODS

A total of 489 pre-biopsy multiparametric magnetic resonance imaging (mpMRI) scans in consecutive patients were subject to prospective paired reporting using both Likert and PI-RADS v2 by expert uro-radiologists. Patients were offered biopsy for any Likert or PI-RADS score ≥4 or a score of 3 with PSA density ≥0.12 ng/mL/mL. Utility was evaluated in terms of proportion biopsied, and proportion of clinically significant and insignificant cancer detected (both overall and on a 'per score' basis). In those patients biopsied, the overall accuracy of each system was assessed by calculating total and partial area under the receiver-operating characteristic (ROC) curves. The primary threshold of significance was Gleason ≥3 + 4. Secondary thresholds of Gleason ≥4 + 3, Ahmed/UCL1 (Gleason ≥4 + 3 or maximum cancer core length [CCL] ≥6 or total CCL≥6) and Ahmed/UCL2 (Gleason ≥3 + 4 or maximum CCL ≥4 or total CCL ≥6) were also used.

RESULTS

The median (interquartile range [IQR]) age was 66 (60-72) years and the median (IQR) prostate-specific antigen level was 7 (5-10) ng/mL. A similar proportion of men met the biopsy threshold and underwent biopsy in both groups (83.8% [Likert] vs 84.8% [PI-RADS v2]; P = 0.704). The Likert system predicted more clinically significant cancers than PI-RADS across all disease thresholds. Rates of insignificant cancers were comparable in each group. ROC analysis of biopsied patients showed that, although both scoring systems performed well as predictors of significant cancer, Likert scoring was superior to PI-RADS v2, exhibiting higher total and partial areas under the ROC curve.

CONCLUSIONS

Both scoring systems demonstrated good diagnostic performance, with similar rates of decision to biopsy. Overall, Likert was superior by all definitions of clinically significant prostate cancer. It has the advantages of being flexible, intuitive and allowing inclusion of clinical data. However, its use should only be considered once radiologists have developed sufficient experience in reporting prostate mpMRI.

Evolution of nectar spur length in a clade of Linaria reflects changes in cell division rather than in cell expansion

BACKGROUND AND AIMS

Nectar spurs (tubular outgrowths of a floral organ which contain, or give the appearance of containing, nectar) are hypothesized to be a 'key innovation' which can lead to rapid speciation within a lineage, because they are involved in pollinator specificity. Despite the ecological importance of nectar spurs, relatively little is known about their development. We used a comparative approach to investigate variation in nectar spur length in a clade of eight Iberian toadflaxes.

METHODS

Spur growth was measured at the macroscopic level over time in all eight species, and growth rate and growth duration compared. Evolution of growth rate was reconstructed across the phylogeny. Within the clade we then focused on Linaria becerrae and Linaria clementei, a pair of sister species which have extremely long and short spurs, respectively. Characterization at a micromorphological level was performed across a range of key developmental stages to determine whether the difference in spur length is due to differential cell expansion or cell division.

KEY RESULTS

We detected a significant difference in the evolved growth rates, while developmental timing of both the initiation and the end of spur growth remained similar. Cell number is three times higher in the long spurred L. becerrae compared with L. clementei, whereas cell length is only 1.3 times greater. In addition, overall anisotropy of mature cells is not significantly different between the two species.

CONCLUSIONS

We found that changes in cell number and therefore in cell division largely explain evolution of spur length. This contrasts with previous studies in Aquilegia which have found that variation in nectar spur length is due to directed cell expansion (anisotropy) over variable time frames. Our study adds to knowledge about nectar spur development in a comparative context and indicates that different systems may have evolved nectar spurs using disparate mechanisms.

Response of 33 UK patients with infantile-onset Pompe disease to enzyme replacement therapy

BACKGROUND

Enzyme replacement therapy (ERT) for infantile-onset Pompe disease has been commercially available for almost 10 years. We report the experience of its use in a cohort treated at three specialist lysosomal treatment centres in the UK.

METHODS

A retrospective case-note review was performed, with additional data being gathered from two national audits on all such patients treated with ERT. The impact on the outcome of various characteristics, measured just prior to the initiation of ERT (baseline), was evaluated using logistic regression.

RESULTS

Thirty-three patients were identified; 13/29 (45%) were cross-reactive immunological material (CRIM) negative, and nine were immunomodulated. At baseline assessment, 79% were in heart failure, 66% had failure to thrive and 70% had radiological signs of focal pulmonary collapse. The overall survival rate was 60%, ventilation-free survival was 40% and 30% of patients were ambulatory. Median follow-up of survivors was 4 years, 1.5 months (range 6 months to 13.5 years). As with previous studies, the CRIM status impacted on all outcome measures. However, in this cohort, baseline failure to thrive was related to death and lack of ambulation, and left ventricular dilatation was a risk factor for non-ventilator-free survival.

CONCLUSION

The outcome of treated patients remains heterogeneous despite attempts at immunomodulation. Failure to thrive at baseline and left ventricular dilation appear to be associated with poorer outcomes.

A pharmacologic investigation of the 'transport response' in the white rat

In a series of six experiments, the ability of specific neurotransmitter antagonists to alter the 'transport response' was investigated in 19-day-old rat pups. The serotonergic blocker, methysergide, and the cholinergic blocker, scopolamine, did not produce any consistent changes in the intensity of the response. Likewise, the opiate receptor blocker, naloxone, was without effect. Large, dose-dependent decreases in transport response intensity were seen with administration of the beta-noradrenergic receptor blocker, propranolol, and with administration of the dopaminergic blocker, haloperidol. The alphanoradrenergic receptor blocker, phentolamine, produced inconsistent changes in the response. These results indicate a central catecholaminergic involvement in the transport response.

Femoral fractures in children, is early interventional treatment beneficial?

A protocol of early intervention (flexible intramedullary nails, early hip spica, and external fixation) was started in 1999 and during a 3-year period there were 25 children who sustained a femoral shaft fracture (early intervention group). These were prospectively reviewed with a minimum follow up of 24 months (Range 24-35 months). A historical control group of 41 children was used. These children were injured between February 1996 and February 1999 and were retrospectively reviewed. They had traditional in patient treatments with either Gallows or Thomas splint traction (traditional treatment group). Over the 6-year period from 1996 to 2002 there were a total of 66 femoral shaft fractures in the study that presented to our hospital. The mean length of hospital stay was 29 nights in the traditional group and 10 nights in the early intervention group. This difference is significant (p<0.001). The malunion rate was slightly higher in the early active group at radiological union but most of these remodelled over the 2 years of follow up. The protocol of early intervention used in our institution, of flexible nails, early hip spica or external fixation depended on the age of the child, and has resulted in a shorter hospital stay for the children. This has benefits for the child, the family and the hospital.

Engineering and public health at CDC

Engineering is the application of scientific and technical knowledge to solve human problems. Using imagination, judgment, and reasoning to apply science, technology, mathematics, and practical experience, engineers develop the design, production, and operation of useful objects or processes. During the 1940s, engineers dominated the ranks of CDC scientists. In fact, the first CDC director, Assistant Surgeon General Mark Hollis, was an engineer. CDC engineers were involved in malaria control through the elimination of standing water. Eventually the CDC mission expanded to include prevention and control of dengue, typhus, and other communicable diseases. The development of chlorination, water filtration, and sewage treatment were crucial to preventing waterborne illness. Beginning in the 1950s, CDC engineers began their work to improve public health while developing the fields of environmental health, industrial hygiene, and control of air pollution. Engineering disciplines represented at CDC today include biomedical, civil, chemical, electrical, industrial, mechanical, mining, and safety engineering. Most CDC engineers are located in the National Institute for Occupational Safety and Health (NIOSH) and the Agency for Toxic Substances and Disease Registry (ATSDR). Engineering research at CDC has a broad stakeholder base. With the cooperation of industry, labor, trade associations, and other stakeholders and partners, current work includes studies of air contaminants, mining, safety, physical agents, ergonomics, and environmental hazards. Engineering solutions remain a cornerstone of the traditional "hierarchy of controls" approach to reducing public health hazards.

Sex attractant pheromone of the red-shouldered stink bug Thyanta pallidovirens: a pheromone blend with multiple redundant components

The male-produced sex pheromone of the red-shouldered stink bug, Thyanta pallidovirens (Stål) (Hemiptera: Pentatomidae) consists of a blend of methyl (E2,Z4,Z6)-decatrienoate (E2,Z4,Z6-10:COOMe), and the sesquiterpenes (+)-alpha-curcumene, (-)-zingiberene, and (-)-beta-sesquiphellandrene. In laboratory bioassays, sexually mature males attracted sexually mature females but not males, and females did not attract either sex. Extracts of volatiles collected from sexually mature males contained compounds not present in extracts from females or sexually immature males, and male-produced extract was attractive to females. Biological activity was lost when the extract was fractionated, indicating that the pheromone consisted of at least two components having different chemical properties. Individually, pheromone components were not attractive to females, but E2,Z4,Z6-10:COOMe in combination with at least one of the three male-produced sesquiterpenes was attractive. The presence of more than one sesquiterpene in the blend did not increase attraction, indicating redundancy in the pheromone signal. Male extract was as attractive as a blend reconstructed from synthesized compounds, indicating all biologically active components had been identified. In bioassays conducted at dusk in a 1- x 1- x 1-m screen field cage, females were attracted to synthetic pheromone lures. In field trials, adult female T pallidovirens were attracted to pheromone-baited traps in relatively low numbers. The profile of volatiles released by sexually mature males of a congeneric species, Thyanta accerra custator McAtee, was remarkably similar to that of male T. pallidovirens, with the exception that the former species produced (E)-2-decenal, a compound that was not found in T. pallidovirens extracts.

A Phase I study of raltitrexed, an antifolate thymidylate synthase inhibitor, in adult patients with advanced solid tumors

The purpose of this study was to perform a Phase I trial of raltitrexed, a selective inhibitor of thymidylate synthase, and to determine the pharmacokinetic and toxicity profiles as a function of raltitrexed dose. Fifty patients with advanced solid tumors and good performance status were treated with raltitrexed as a 15-min i.v. infusion every 3 weeks, at doses escalating from 0.6 to 4.5 mg/m2. Asthenia, neutropenia, and hepatic toxicity were the most common dose-limiting toxicities in this largely pretreated patient population, but they occurred during the initial cycle in only one of nine patients treated with 4.0 mg/m2 and in two of nine patients treated with 4.5 mg/m2. Only 2 of 13 patients treated with 3.5 mg/m2 ultimately experienced unacceptable toxicity after three and seven cycles, compared with 42 and 56% of patients receiving 4.0 and 4.5 mg/m2 after medians of three and two cycles, respectively. The maximum raltitrexed plasma concentration and the area under the plasma concentration-time curve increased in proportion to dose. Raltitrexed clearance was independent of dose and was associated with the estimated creatinine clearance. Asthenia, neutropenia, and hepatic transaminitis were dose-related and tended to occur more frequently when patients received three or more cycles of therapy. A 3-week treatment interval was feasible in the majority of patients at all doses. Although 4.0 mg/m2 appeared to be a safe starting dose in this pretreated patient population, about half who received two or more courses ultimately experienced dose-limiting toxicity. A dose of 3.5 mg/m2 was well tolerated in most patients.

The utility of monitoring carcinoembyronic antigen during systemic therapy for advanced colorectal cancer

To determine if pre-treatment serum carcinoembryonic antigen (CEA) levels or changes in CEA values during treatment have prognostic value, we reviewed five prior fluorouracil/leucovorin-based trials and identified 125 colorectal cancer patients with no prior chemotherapy for metastatic disease in whom CEA values were available. Although pre-treatment serum CEA values did not predict for clinical response or time to progression, serial monitoring of CEA appeared to be useful in patients with an elevated pre-treatment CEA, particularly when a decrease in CEA occurred in concert with radiographic evidence of disease response. The CEA nadir was a strong prognostic variable with respect to time to disease progression. A consistent rise in CEA values over the minimum value signals the need for radiographic re-assessment of the patient's disease status to rule out disease progression.

Transmembrane-truncated alphavbeta3 integrin retains high affinity for ligand binding: evidence for an 'inside-out' suppressor?

The molecular mechanisms of alphavbeta3 integrin affinity regulation have important biological implications in tumour development, wound repair and angiogenesis. We expressed, purified and characterized recombinant forms of human alphavbeta3 (r-alphavbeta3) and compared the activation state of these with alphavbeta3 in its cellular environment. The ligand specificity and selectivity of recombinant full-length and double transmembrane truncations of r-alphavbeta3 cloned in BacPAK6 vectors and expressed in Sf9 and High Five insect cells were compared with those of native placental alphavbeta3 and the receptor in situ on the cell surface. r-alphavbeta3 integrins were purified by affinity chromatography from detergent extracts of cells (full-length), and from the culture medium of cells expressing double-truncated r-alphavbeta3. r-alphavbeta3 had the same epitopes, ligand-binding specificities, bivalent cation requirements and susceptibility to RGD-containing peptides as native alphavbeta3. On M21-L4 melanoma cells, alphavbeta3 mediated binding to vitronectin, but not to fibrinogen unless activated with Mn2+. Non-activated alphaIIbbeta3 integrin as control in M21-L-IIb cells had the opposite profile, mediating binding to fibrinogen, but not to vitronectin unless activated with Mn2+. Thus these receptors had moderate to low ligand affinity. In marked contrast, purified alphavbeta3 receptors, with or without transmembrane and cytoplasmic domains, were constitutively of high affinity and able to bind strongly to vitronectin, fibronectin and fibrinogen under physiological conditions. Our data suggest that, in contrast with the positive regulation of alphaIIbbeta3 in situ, intracellular controls lower the affinity of alphavbeta3, and the cytoplasmic domains may act as a target for negative regulators of alphavbeta3 activity.

A pilot study of gamma-1b-interferon in combination with fluorouracil, leucovorin, and alpha-2a-interferon

The combination of IFN-alpha-2a (IFN-alpha) and IFN-gamma-1b (IFN-gamma) has been found to produce more than additive cytotoxicity with fluorouracil (5-FU) in HT 29 colon cancer cells due to enhanced DNA-directed effects. We therefore studied the combination of IFN-gamma with IFN-alpha, 5-FU, and leucovorin (LV) in a clinical trial. Fifty-three patients received an initial cycle of 5 million units (MU)/m2 IFN-alpha s.c. on days 1-7 with 500 mg/m2 LV and 370 mg/m2 5-FU i.v. on days 2-6. IFN-gamma was then added once tolerable doses of 5-FU and IFN-alpha were established for each patient. IFN-gamma was administered at one of six dose levels between 0.3-4.8 MU/m2 s.c. on days 1-7. This design permitted comparison of the clinical toxicity and pharmacokinetics of 5-FU in two consecutive cycles in an individual treated with the same doses of 5-FU/LV/IFN-alpha in the absence and presence of IFN-gamma. In 43 matched patient cycles, the addition of IFN-gamma did not seem to worsen gastrointestinal toxicity, and skin toxicity tended to be milder. 5-FU clearance was higher in 14 cycles with IFN-gamma compared to the patient's prior cycle with the same doses of 5-FU/LV/IFN-alpha: 798 +/- 309 versus 601 +/- 250 ml/min/m2 (mean +/- SD; P = 0.04). In these 28 cycles, the median 5-FU clearance was significantly lower in 11 cycles that were complicated by more severe diarrhea: 524 versus 798 ml/min/m2 (grade 2 versus 0-1; P = 0. 0032). Overall, 38% and 26% of patients had grade 3-4 diarrhea and mucositis. Dose reductions of IFN-gamma for chronic fatigue, malaise, or anorexia were ultimately required more frequently with >/=2.4 MU/m2 (P = 0.018), and the maximum tolerated dose of IFN-gamma was considered to be 1.2 MU/m2/ day. Objective responses were seen in 41% of 29 measurable colorectal cancer patients. Compared to our previous experience with 5-FU/LV/IFN-alpha, IFN-gamma and IFN-alpha appeared to have opposite effects on 5-FU clearance. These results suggest that any potential benefit of adding IFN-alpha to 5-FU/LV on this schedule may not depend solely on alterations in 5-FU clearance.

Novel non-nucleoside inhibitors of human immunodeficiency virus type 1 (HIV-1) reverse transcriptase. 4. 2-Substituted dipyridodiazepinones as potent inhibitors of both wild-type and cysteine-181 HIV-1 reverse transcriptase enzymes

The major cause of viral resistance to the potent human immunodeficiency virus type 1 reverse transcriptase (RT) inhibitor nevirapine is the mutation substituting cysteine for tyrosine-181 in RT (Y181C RT). An evaluation, against Y181C RT, of previously described analogs of nevirapine revealed that the 2-chlorodipyridodiazepinone 16 is an effective inhibitor of this mutant enzyme. The detailed examination of the structure-activity relationship of 2-substituted dipyridodiazepinones presented below shows that combined activity against the wild-type and Y181C enzymes is achieved with aryl substituents at the 2-position of the tricyclic ring system. In addition, the substitution pattern at C-4, N-5, and N-11 of the dipyridodiazepinone ring system optimum for inhibition of both wild-type and Y181C RT is no longer the 4-methyl-11-cyclopropyl substitution preferred against the wild-type enzyme but rather the 5-methyl-11-ethyl (or 11-cyclopropyl) pattern. The more potent 2-substituted dipyridodiazepinones were evaluated against mutant RT enzymes (L100I RT, K103N RT, P236L RT, and E138K RT) that confer resistance to other non-nucleoside RT inhibitors, and compounds 42, 62, and 67, with pyrrolyl, aminophenyl, and aminopyridyl substituents, respectively, at the 2-position, were found to be effective inhibitors of these mutant enzymes also.

3T3 cell surface galactosyltransferase is a calcium-dependent adhesion molecule for collagen type IV

Cell surface galactosyltransferase (GalTase) has been previously shown to mediate cell spreading or migration on laminin matrices. This work demonstrates that 3T3 cell surface GalTase also mediates cell attachment to collagen type IV. Attachment to collagen type IV was blocked by perturbations of GalTase or substrate pregalactosylation on cells possessing only calcium-dependent mechanisms of adhesion. Cells with both calcium-dependent and calcium-independent systems were not affected by GalTase perturbation. Collagen type IV was shown to possess GalTase substrates since matrices could be galactosylated by both soluble enzyme and 3T3 cells.

Novel non-nucleoside inhibitors of HIV-1 reverse transcriptase. 2. Tricyclic pyridobenzoxazepinones and dibenzoxazepinones

Dibenz[b,f][1,4]oxazepin-11(10H)-ones (III), pyrido[2,3-b][1,4]benzoxazepin-6(5H)-ones (IV), and pyrido[2,3-b]- [1,5]benzoxazepin-5(6H)-ones (V) were found to inhibit human immunodeficiency virus type 1 reverse transcriptase with IC50 values as low as 19 nM. A-ring substitution has a profound effect on activity, with appropriate substituents at the positions ortho and para to the lactam nitrogen providing dramatically enhanced potency. Substitution in the C-ring is generally neutral or detrimental to activity. Although a C-ring amino substituent at the position meta to the lactam carbonyl is generally beneficial to activity, it has essentially no effect when the A-ring is optimally substituted. Like the dipyridodiazepinone nevirapine, compounds III-V are specific for HIV-1 RT, exhibiting no inhibitory activity against HIV-2 RT or other virial reverse transcriptase enzymes.

Bis basic substituted diaminobenzobisthiazoles as potential antiarthritic agents

A series of benzobisthiazoles were screened for antiinflammatory activity in the carrageenan paw edema and adjuvant arthritis tests. Compound 26, 2,6-bis(N,N-diethylamino)benzo[1,2-d:5,4-d']bisthiazole, was found to inhibit the swelling of the uninjected paw in the prophylactic adjuvant arthritis model with an ED50 of 2.3 mg/kg orally. As with most compounds of this series, 26 was inactive in acute model of inflammation, such as paw edema; like steroids, it showed activity in the granuloma pouch assay but did not inhibit cyclooxygenase, indicating a mode of action different from the classical nonsteroidal antiinflammatory drugs (NSAID's). At doses higher than those producing antiinflammatory activity, 26 had some immunoregulating properties.

Novel non-nucleoside inhibitors of HIV-1 reverse transcriptase. 1. Tricyclic pyridobenzo- and dipyridodiazepinones

Novel pyrido[2,3-b][1,4]benzodiazepinones (I), pyrido[2,3-b][1,5]benzodiazepinones (II), and dipyrido[3,2-b:2',3'-e][1,4]diazepinones (III) were found to inhibit human immunodeficiency virus type 1 (HIV-1) reverse transcriptase in vitro at concentrations as low as 35 nM. In all three series, small substituents (e.g., methyl, ethyl, acetyl) are preferred at the lactam nitrogen, whereas slightly larger alkyl moieties (e.g., ethyl, cyclopropyl) are favored at the other (N-11) diazepinone nitrogen. In general, lipophilic substituents are preferred on the A ring, whereas substitution on the C ring generally reduces potency relative to the corresponding compounds with no substituents on the aromatic rings. Maximum potency is achieved with methyl substitution at the position ortho to the lactam nitrogen atom; however, in this case an unsubstituted lactam nitrogen is preferred. Additional substituents on the A ring can be readily tolerated. The dipyridodiazepinone derivative 11-cyclopropyl-5,11-dihydro-4-methyl-6H-dipyrido[3,2-b:2',3'-e] [1,4]diazepin-6-one (96, nevirapine) is a potent (IC50 = 84 nM) and and selective non-nucleoside inhibitor of HIV-1 reverse transcriptase, and has been chosen for clinical evaluation.

CONTRIBUTION À L'ÉTUDE DE LA RÉACTION DE VON RICHTER: IV. COMMENTAIRES CONCERNANT LA RÉACTION

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CONTRIBUTION À L'ÉTUDE DE LA RÉACTION DE VON RICHTER: III. SUR LA RÉACTION AVEC DIVERS NITRONAPHTALÈNES

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CONTRIBUTION À L'ÉTUDE DE LA RÉACTION DE VON RICHTER: II. SUR L'IDENTIFICATION DE PRODUITS NEUTRES

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CONTRIBUTION À L'ÉTUDE DE A RÉACTION DE VON RICHTER: I. SUR L'IDENTIFICATION DE QUELQUES PRODUITS ACIDES

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