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Clinical and molecular prognostic factors in newly diagnosed pediatric T-cell lymphoblastic lymphoma: a prospective, multicenter, single-arm phase 2 clinical trial.

BACKGROUND: Poor early treatment response in T-cell lymphoblastic lymphoma (T-LBL) is associated with an unfavorable prognosis. This multicenter prospective study evaluated the efficacy of the response-adjusted Chinese Children's Cancer Group (CCCG-LBL-2016) protocol for pediatric T-LBL and examined clinical and molecular prognostic factors. METHODS: Clinical and laboratory data from seven pediatric oncology centers were analyzed. A sub-cohort of 23 patients underwent exploratory integrated genomic analysis, including targeted next-generation sequencing, RNA sequencing, and copy-number array analysis. Survival was evaluated using the Kaplan-Meier method, and prognostic factors were analyzed using multivariable Cox proportional hazards regression. RESULTS: A total of 163 patients (median age: 108&#xa0;months; 116 males, 47 females) were enrolled, most with advanced disease (stage III: 81.0%; stage IV: 17.8%). Patients were stratified into the low-risk (R1, n&#x2009;=&#x2009;2) and intermediate-risk groups (R2, n&#x2009;=&#x2009;161); thirty one patients in the R2 group were escalated to the high-risk intensified regimen (R3) due to poor early response. The 3-year overall survival (OS) was 78.6%&#x2009;&#xb1;&#x2009;3.3% and event-free survival (EFS) was 73.9%&#x2009;&#xb1;&#x2009;3.5%. Outcomes differed by risk group (P&#x2009;<&#x2009;0.05), with 3-year OS and EFS of 100% and 100% in R1, 82.6%&#x2009;&#xb1;&#x2009;3.4% and 79.5%&#x2009;&#xb1;&#x2009;3.4% in R2, and 58.6%&#x2009;&#xb1;&#x2009;9.1% and 48.3%&#x2009;&#xb1;&#x2009;9.1% in R3. Progression or recurrence occurred in 42 patients (median: 7&#xa0;months; 3-year OS: 17.1%&#x2009;&#xb1;&#x2009;6.3%). Clinical risk factors included R3 assignment and elevated lactate dehydrogenase. In the exploratory molecular sub-cohort, recurrent alterations included CDKN2A (39.1%), NOTCH1 (26.1%), FBXW7 (21.7%), and MTAP/PIK3R1/NRAS (13.0%). Exploratory multivariable Cox regression analysis identified that CDKN2A alteration was associated with an increased risk of progression or recurrence (hazard ratio&#x2009;=&#x2009;35.89, 95% confidence interval: 3.07-419, P&#x2009;=&#x2009;0.004). CONCLUSIONS: Adjusting the risk stratification based on treatment response significantly improved the overall prognosis of T-LBL. However, survival rates remain very low among patients who experience disease progression or recurrence. The preliminarily explored molecular genetic risk factors might contribute to further risk stratification and provide potential therapeutic targets.

Humans

Transdermal 17&#x3b2;-Estradiol for the Treatment of COVID-19: Protocol of an Early Terminated Phase 2 Randomized Controlled Trial.

BACKGROUND: Early epidemiological studies suggested that pre- and postmenopausal women receiving estrogen therapy were less likely to develop severe disease or die from COVID-19 infection. Potential mechanisms include estrogen-mediated immunomodulation and 17&#x3b2;-estradiol-induced downregulation of angiotensin-converting enzyme type 2 (ACE2), the cellular receptor for SARS-CoV-2. OBJECTIVE: This study aimed to evaluate the feasibility, safety, and preliminary efficacy of transdermal 17&#x3b2;-estradiol as an adjunctive treatment for COVID-19 in men and postmenopausal women. METHODS: We designed and conducted a randomized controlled trial comparing 17&#x3b2;-estradiol transdermal gel plus standard care with standard care alone in adults with confirmed COVID-19. Initial ethics and funding approvals were obtained in March 2021. Owing to changes in the epidemiology of COVID-19 in Qatar and revisions to national quarantine policies, protocol amendments were required before recruitment commenced in February 2022. The treatment duration was reduced from 10 to 7 days due to changes in national quarantine guidelines. Recruitment and follow-up were conducted between February 2022 and June 2022. RESULTS: Recruitment was substantially lower than anticipated because widespread COVID-19 vaccination, declining disease severity, and revised national quarantine policies markedly reduced the number of eligible hospitalized patients. Consequently, the planned sample size was not achieved, and the study was terminated in June 2022. A total of 29 men with mild COVID-19 were enrolled, with 44.8% (n=13) randomized to standard care and 55.2% (n=16) to transdermal 17&#x3b2;-estradiol plus standard care. The intervention was well tolerated, with no adverse safety signals or thromboembolic events reported. CONCLUSIONS: Although the study was underpowered to assess efficacy because recruitment targets were not achieved, it showed that transdermal 17&#x3b2;-estradiol was well tolerated, with no major safety concerns among enrolled participants. The experience also provided important operational lessons for conducting clinical trials during rapidly evolving pandemics. Adequately powered studies are required to determine whether transdermal estrogen has therapeutic potential against COVID-19, other ACE2-mediated coronavirus infections, or potentially other severe viral illnesses.

Humans

Phase 2 study with Baker's Antifol in solid tumors.

One hundred thirty-eight adults with advanced cancers were treated with Baker's Antifol. The complete response + partial response rate was only 10%. Best responses were obtained in 31 patients with lung adenocarcinoma (complete response + partial response, 13%), in 25 patients with colorectal carcinoma (partial response, 16%), and in 6 patients with renal cell carcinoma (partial response, 50%). Two partial responses occurred in 15 patients with squamous cancer. No significant responses were seen in 27 patients with other adenocarcinomas, 13 with sarcomas, 14 with melanomas, and 8 with miscellaneous tumors. The most frequent toxicities were dermatitis, stomatitis, gastrointestinal symptoms, and mild myelosuppression. The incidence of dermatitis was significantly decreased by shortening the schedule of Baker's Antifol administration from 5 to 3 days. Baker's Antifol has some degree of antitumor activity, and studies of combination of this agent with other effective chemotherapeutic agents are indicated.

Adenocarcinoma

Ifebemtinib plus garsorasib in previously treated metastatic colorectal cancer with KRASG12C mutation: a multicentre, randomised, phase 1b/2 trial.

BACKGROUND: Ifebemtinib is a potent oral focal adhesion kinase inhibitor. Preclinical evidence supports combining ifebemtinib with the KRASG12C inhibitor garsorasib. This study aimed to evaluate this combination in KRASG12C-mutated solid tumours. METHODS: This multicentre, phase 1b/2 study had a phase 1b component to establish the recommended phase 2 dose and a phase 2 multitumour expansion component. In phase 1b, the safety and tolerability of ifebemtinib combined with garsorasib was assessed using a 3&#x2008;+&#x2008;3 design in KRASG12C-mutated solid tumours. No dose-limiting toxic effects were observed, and the recommended phase 2 dose was established as ifebemtinib 100 mg orally once daily plus garsorasib 600 mg orally twice daily. Here, we report the results of the cohort of previously treated KRASG12C-mutated metastatic colorectal cancer from phase 2 expansion. Eligible patients (aged &#x2265;18 years) who had histologically confirmed locally advanced or metastatic colorectal cancer harbouring the KRASG12C mutation, an Eastern Cooperative Oncology Group performance-status score of 0 or 1, and had disease progression after previous irinotecan-based or oxaliplatin-based combination therapy, were recruited from seven of nine participating tertiary hospitals in China. On the basis of the recommended phase 2 dose, phase 2 comprised a single-arm study to evaluate the safety and efficacy of ifebemtinib combined with garsorasib and an open-label, randomised study in which patients were randomly assigned (1:1) to receive ifebemtinib plus garsorasib or garsorasib alone, by use of centralised computer-generated block randomisation with no stratification. Investigators were masked to the block size. The primary efficacy endpoint of phase 2 was investigator-assessed objective response rate (Response Evaluation Criteria in Solid Tumours, version 1.1), assessed in the safety analysis set in the single-arm study and in all randomly assigned patients (intention-to-treat population) in the randomised study. At least six objective responses (safety analysis set) were required in the single-arm study to proceed to the randomised study. This study is registered with ClinicalTrials.gov, NCT06166836 and NCT05379946, and is active but not recruiting. FINDINGS: Between April 7, 2023 and Dec 13, 2024, 51 patients were enrolled in phase 2 (15 in the single-arm study and 36 in the randomised study). In the single-arm study, the median age was 53 years (IQR 39 to 63), nine (60%) patients were female, six (40%) were male, and all were Asian. In the randomised study, the median age was 51 years (IQR 42 to 59) in the combination group and 63 years (IQR 54 to 66) in the monotherapy group, 24 (67%) were female, 12 (33%) were male, and all patients were Asian. In the single-arm part, the confirmed objective response rate was 46&#xb7;7% (95% CI 21&#xb7;3 to 73&#xb7;4). Seven patients had partial responses, triggering progression to the randomised study. In the randomised study, the confirmed objective response rate was 38&#xb7;9% (95% CI 17&#xb7;3 to 64&#xb7;3) with the combination therapy versus 16&#xb7;7% (95% CI 3&#xb7;6 to 41&#xb7;4) with garsorasib alone (between-group difference 22&#xb7;2%, 95% CI -7&#xb7;7 to 49&#xb7;1; one-sided p=0&#xb7;068). In the single-arm study, grade 3 treatment-related adverse events occurred in four (27%) of 15 patients, and in the randomised study, grade 3 treatment-related adverse events occurred in six (33%) of 18 patients in the combination group and five (28%) of 18 in the garsorasib group. Grade 3 treatment-related adverse events occurring in at least two patients were diarrhoea (six [18%]), proteinuria (two [6%]), and intestinal obstruction (two [6%]) in patients treated with combination therapy (combined), and increased alanine aminotransferase and &#x3b3;-glutamyltransferase (two [11%] each) in patients treated with garsorasib alone. Serious adverse events occurred in ten (30%) patients in the combination group and in four (22%) patients in the monotherapy group. One patient in the garsorasib monotherapy group died due to the underlying malignancy within 30 days after completing study treatment, which was reported as a serious adverse event. The death was assessed by the investigators as not related to garsorasib. No grade 4 treatment-related adverse events or treatment-related deaths were reported across all cohorts. INTERPRETATION: The combination of ifebemtinib and garsorasib showed promising anticancer activity and manageable safety profile in previously treated patients with KRASG12C-mutated metastatic colorectal cancer. Although the improvement in response rate did not reach statistical significance in the randomised study, these findings support further evaluation of ifebemtinib plus garsorasib in this population. FUNDING: InxMed, InventisBio, National Natural Science Foundation of China, the Jian Bing Ling Yan + X Research and Development Program of Zhejiang Province, and the Zhejiang Province Medical and Health Science and Technology Plan Project.

Humans

Trastuzumab Deruxtecan for ERBB2-Mutant Metastatic Non-Small Cell Lung Cancer With or Without Brain Metastases: A Secondary Analysis of Randomized Clinical Trials.

IMPORTANCE: Brain metastases reduce overall survival rates of patients with non-small cell lung cancer (NSCLC); patients with epidermal growth factor receptor 2 (ERBB2 [formerly HER2])-mutant NSCLC are more likely to have baseline brain metastases. Trastuzumab deruxtecan (T-DXd) is an approved ERBB2-directed treatment for previously treated unresectable or metastatic ERBB2-mutant NSCLC. OBJECTIVE: To assess the clinical effectiveness and safety of T-DXd 5.4 mg/kg and 6.4 mg/kg doses in patients with previously treated ERBB2-mutant metastatic NSCLC with or without untreated or previously treated stable brain metastases. DESIGN, SETTING, AND PARTICIPANTS: This post hoc secondary analysis pooled patients from the DESTINY-Lung01 (data cutoff date: December 3, 2021) and DESTINY-Lung02 (data cutoff date: December 23, 2022) clinical trials by T-DXd dose (5.4 mg/kg and 6.4 mg/kg). DESTINY-Lung01 was a multicenter, open-label, 2-cohort, nonrandomized phase 2 study, while DESTINY-Lung02 was a dose-blinded, multicenter, 2-cohort, randomized phase 2 study. Participants had a previously treated ERBB2-mutant metastatic NSCLC with or without untreated or previously treated stable brain metastases at baseline. All statistical analyses were performed from April 2023 to October 2024. INTERVENTION: Patients received a T-DXd dose of either 5.4 mg/kg or 6.4 mg/kg intravenously every 3 weeks. MAIN OUTCOME AND MEASURE: Systemic and intracranial effectiveness by blinded independent central review using RECIST (Response Evaluation Criteria in Solid Tumors) version 1.1, sites of progression, and safety. RESULTS: This analysis included 102 patients in the T-DXd 5.4-mg/kg dose group (65 females [64%]; median [range] age, 57.5 [37.0-83.0] years and 59.5 [30.0-79.0] years in patients with and without brain metastases, respectively) and 141 patients in the T-DXd 6.4-mg/kg dose group (94 females [67%]; median [range] age, 62.5 [29.0-88.0] years and 59.0 [27.0-83.0] years in patients with and without brain metastases, respectively). In each group, 31% (32 of 102) and 38% (54 of 141) of patients, respectively, had baseline brain metastases and 53% (17 of 32) and 44% (24 of 54), respectively, received prior brain metastasis treatment. In patients with and without brain metastases, systemic confirmed objective response rates (ORRs) were 47% (15 of 32; 95% CI, 29%-65%) and 50% (35 of 70; 95% CI, 38%-62%), respectively, with the T-DXd 5.4-mg/kg dose, and 50% (27 of 54; 95% CI, 36%-64%) and 59% (51 of 87; 95% CI, 48%-69%) with the T-DXd 6.4-mg/kg dose. Median progression-free survival was 7.1 (95% CI, 5.5-9.7) months in the T-DXd 5.4-mg/kg dose group and 7.1 (95% CI, 4.5-9.6) months in the T-DXd 6.4-mg/kg dose group of patients with baseline brain metastases. Among patients with measurable baseline brain metastases, intracranial confirmed ORRs were 50% (7 of 14; 95% CI, 23%-77%) with the T-DXd 5.4-mg/kg dose and 30% (9 of 30; 95% CI, 15%-49%) with the T-DXd 6.4-mg/kg dose. At both doses, the safety profile of T-DXd was generally manageable, regardless of baseline brain metastases, favoring the T-DXd 5.4 mg/kg dose. CONCLUSIONS AND RELEVANCE: In this secondary analysis, T-DXd at the approved dose of 5.4 mg/kg showed antitumor activity in patients with previously treated ERBB2-mutant metastatic NSCLC with or without brain metastases. This finding supports T-DXd 5.4 mg/kg use in this population.

Adult

A study of the macro and micro immunoglobulins to Brucella abortus and their transfer from cow to calf via the colostrum.

Samples of adult bovine serum, colostrum, the serum of unsuckled and suckled calves were subjected to gel filtration through Sephadex G 200. All samples (except those of unsuckled calves) contained antibodies to Brucella abortus. Four phases were recorded in normal adult serum corresponding to IgM, IgG, Albumin and a fourth phase of smaller nitrogen-containing molecules. In colostrum phase 2 was relatively large and phase 3 was absent indicating absence of albumin. In the serum of the unsuckled calves phase 2 was absent, indicating a virtual absence of IgG. Agglutinins and Complement fixing antibodies were found in the fractions of both phase 1 and phase 2. Incomplete antibodies occurred only in phase 2, which suggested that they occurred only as 7S molecules. By immunising pregnant heifers shortly before calving with formalin Killed Strain 19 vaccine, it was found that serum IgM may be secreted in colostrum and in this manner transferred to the calf on suckling. It is considered that the immunoglobulins of importance in protecting the young calf from Br. abortus, and also in neutralising Strain 19 vaccination, are of the IgG incomplete (7S) class. These antibodies appear to be less heat-labile than 7S agglutinins.

Animals

Very slow growth of Escherichia coli.

A recycling fermentor (a chemostat with 100% biomass feedback) was used to study glucose-limited behavior of Escherichia coli B. The expectation from mass transfer analysis that growth would asymptotically approach a limit mass determined by the glucose provision rate (GPR) and the culture's maintenance requirement was not met. Instead, growth proceeded at progressively lower rates through three distinct phases. After the fermentor was seeded, but before glucose became limiting, growth followed the usual, exponential path (phase 1). About 12 h postseeding, residual glucose in the fermentor fell below 1 microgram . ml-1 and the growth rate (dx/dt) became constant and a linear function of GPR (phase 2). The specific growth rate, mu, therefore fell continuously throughout the phase. Biomass yield and glucose assimilation (13%) were near the level for exponential growth, however, and independent of GPR over a broad range. At a critical specific growth rate (0.04 h-1 for this strain), phase 2 ended abruptly and phase 3 commenced. In phase 3, the growth rate was again constant, although lower than in phase 2, so that mu continued to fall, but growth rates and yields were praboloid functions of GPR. They were never zero, however, at any positive value of GPR. By inference, the fraction of metabolic energy used for maintenance functions is constant for a given GPR, although different for phases 2 and 3, and independent of biomass. In both phases 2 and 3, orcinol, diphenylamine, and Lowry reactive materials were secreted at near-constant rates such that over 50% as much biosynthetic mass was secreted as was retained by the cells.

Adenosine Triphosphate

Clinical trials in cancer chemotherapy.

The success of cancer chemotherapy has increased greatly the potential areas for its inclusion in clinical trials and therefore has made the experimental design considerations more complex in these trials. New drugs still go through the three classic phases of clinical study beginning with clinical pharmacology (Phase I), efficacy screening (Phase 2) and role delineation (Phase 3). The Phase 2 and 3 trials now need to be considered within the overall therapeutic strategies which are required for each of the many diseases which are called cancer. The exigencies of a disease-oriented strategy which requires a blend of therapeutic modalities many times require a modification of what would be an ideal modality-oriented strategy geared solely to effectively testing a new agent. A new drug may need many Phase 2 and 3 trials in a variety of tumors before it can be considered adequately evaluated. Essential aspects of valid clinical trials include an adequate protocol which details the study and a design which is feasible for answering the question. Historical controls are advocated by many as a valid approach to clinical trials. Unless the numbers in the historical control are large and the prognostic variables well matches this approach should be viewed cautiously by the practicing physician.

Animals

Chemoradiotherapy versus short-course radiotherapy for response-adapted organ preservation in early-stage and intermediate-stage rectal cancer (STAR-TREC): 12-month results of an international, multicentre, open-label, parallel-group, randomised, phase 2/3 trial.

BACKGROUND: Total mesorectal excision (TME) is the standard treatment for most early-stage and intermediate-stage rectal cancer but can cause substantial perioperative morbidity, functional impairment, and reduced quality of life. We assessed whether long-course chemoradiotherapy (LCCRT) or short-course radiotherapy (SCRT) could increase organ preservation and reduce surgery, toxicity, and quality-of-life harms without compromising oncological outcomes. METHODS: STAR-TREC is an international, multicentre, open-label, parallel-group, randomised, phase 2/3 trial in five European countries. Eligible patients were aged 16 years or older in the UK or aged 18 years or older elsewhere, had an Eastern Cooperative Oncology Group (ECOG) performance status of 0-1, and rectal adenocarcinoma (&#x2264;40 mm staged as mrT1-T3bN0). In phase 2, participants were randomly assigned (1:1:1) to LCCRT-based organ preservation (LCCRT-OP; 50 Gy in 25 fractions plus oral capecitabine 825 mg/m2 twice daily), SCRT-based organ preservation (SCRT-OP; 25 Gy in five fractions), or primary TME. Phase 2 assessed feasibility, with recruitment at months 12 and 24 as the primary endpoint and feasibility thresholds of four or more and six or more randomisations per month, respectively. Phase 3 adopted a partially randomised patient-preference design, allowing participants to choose either organ preservation or TME. Participants that chose organ preservation were randomly assigned (1:1) to receive LCCRT-OP or SCRT-OP using centralised, computer-generated assignment, with stratification by country and MRI T category (&#x2264;T3a vs T3b) using minimisation. The phase 3 primary endpoint was organ-preservation 30 months after treatment initiation, defined as absence of TME, stoma, or local recurrence, which was assessed in the modified intention-to-treat population, which included participants in phase 2 and phase 3. After a planned interim analysis of unmasked phase 2 data, the trial steering committee and independent data monitoring committee recommended reporting a 12-month, modified intention-to-treat analysis of implementation outcomes for participants recruited before Aug 8, 2023. This study is registered with ISRCTN (14240288) and is closed. FINDINGS: Between June 14, 2017, and April 8, 2024, 503 participants were enrolled at 37 sites. Phase 2 enrolled 120 participants, with recruitment rates of three and six participants per month at months 12 and 24, respectively. Overall, 12-month TME-free survival was 60% (47 of 78 participants). After phase 3 recruitment ended, interim analysis of unmasked phase 2 data showed an early TME-free survival benefit with LCCRT versus SCRT (12-month median TME-free survival not reached [95% CI not reached-not reached] vs 7&#xb7;6 months [95% CI 6&#xb7;4-not reached]; hazard ratio [HR] 3&#xb7;7 [95% CI 1&#xb7;7-8&#xb7;0]; posterior probability of superiority >99&#xb7;5%). The trial steering committee and independent data monitoring committee therefore recommended expanded analysis of 426 participants recruited before Aug 8, 2023: 120 from phase 2 and 306 from phase 3. 17 participants withdrew before treatment, leaving 409 in the modified intention-to-treat population: 163 allocated to LCCRT, 168 to SCRT, and 78 to primary TME. 116 (28%) participants were female and 293 (72%) were male. Among participants who opted for organ preservation, 12-month TME-free survival was 78&#xb7;5% (95% CI 72&#xb7;4-85&#xb7;1) with LCCRT and 60&#xb7;6% (53&#xb7;6-68&#xb7;4) with SCRT (HR 1&#xb7;90 [95% CI 1&#xb7;29-2&#xb7;81]). The most common grade 3-4 serious adverse events were gastrointestinal disorders (four [2%] with LCCRT vs six [4%] with SCRT vs six [8%] with TME) and procedural complications (three [2%] with LCCRT vs five [3%] with SCRT vs five [6%] with TME). One participant allocated to primary TME died after an anastomotic leak. INTERPRETATION: These early results support a response-adapted organ-preservation approach, with LCCRT appearing more effective than SCRT at 12 months. Organ-preservation might also reduce treatment-related toxicity compared with primary TME. Longer follow-up is needed for the prespecified 30-month endpoint and definitive functional and oncological outcomes. FUNDING: Cancer Research UK, Stand Up to Cancer, Dutch Cancer Society, Danish Cancer Society, Kom Op Tegen Kanker, Cancerfonden, ALF Region Stockholm, RCC Region Stockholm.

Humans

Removal of gamma-II phase in amalgam.

To examine the quantitative change in the gamma 2 phase, specimens of three conventional, four dispersed-phase and two ternary amalgams were prepared. A higher energy amalgamator caused more gamma 2 phase to be formed in conventional amalgam and less in the dispersed-phase material. With storage at 37 degrees C this gamma 2 phase decreased quantitatively in dispersed-phase amalgams over one week but not in conventional amalgams. The selective etch system of gamma 2 did not disclose this phase in the ternary amalgams.

Chemical Phenomena

Tension responses to sudden length change in stimulated frog muscle fibres near slack length.

1. Apparatus for applying a step change of length to an isolated muscle fibre is described. The step was complete in about 0.2 ms.2. Effects of tendon compliance were eliminated by using a spot-follower device and by gripping the tendons with metal clips close to the fibre ends.3. The natural frequency of the force transducer was above 10 kHz.4. Steps of various amplitudes and in either direction were applied to isolated muscle fibres about 6 mm long from the anterior tibial muscle of Rana temporaria during tetanic stimulation. Initial sarcomere length was 2.0-2.2 mum, and temperature was 0-3 degrees C.5. The tension response to a step could be divided into four phases. The initial response was an apparently elastic change during the step itself (phase 1). After the step was completed there was a rapid partial recovery towards the original tension (phase 2, lasting 2-5 ms), followed by a slowing or reversal of recovery (phase 3, 10-50 ms), and finally a much slower return to the original tension (phase 4). Most of this paper is concerned with phases 1 and 2.6. The initial tension change (phase 1) occurred synchronously with the applied length change, indicating that the fibres possess a compliance which is almost linear and almost undamped. Its stiffness is such that an instantaneous shortening of about 4 nm per half-sarcomere would bring the tension to zero from its isometric value.7. The absence of detectable damping during phase 1 indicates that the viscosity of a stimulated fibre is substantially less than the apparent viscosity of a fibre at rest.8. The instantaneous force-extension curve approached the length axis at a sharp angle and a negative tension appeared at the force transducer when a very large step was applied. These observations suggest that the structures responsible for the stiffness of the fibre remain rigid when they are not under tension.9. During the few milliseconds after the step (phase 2) the tension recovered part of the way toward the level which existed before the step. In shortening steps the time course of this recovery was adequately fitted by the sum of four exponential terms, and was similar in steps of different amplitude but with a time scale shorter the larger the step. In stretches the slow components were relatively larger than in releases.10. The tension level, T(2), approached during phase 2 depended only on the total amplitude of the step and not on the time course of the length change, provided it was complete in 1-2 ms. The extreme tension reached during a step could thus vary widely without detectable change in T(2).11. With stretches and releases of up to about 3 nm per half-sarcomere this early recovery was almost complete, so that the curve of T(2) against step amplitude was nearly horizontal. With larger releases the line curved downwards, reaching zero in a release of about 14 nm per half-sarcomere.12. When the temperature was raised both the developed tension and the stiffness increased, but the relative increase was greater for tension than for stiffness. The amount of instantaneous shortening needed to bring tension to zero was therefore also increased.13. A set of empirical equations is given which describe adequately the first few milliseconds of the tension change in response to any imposed time course of shortening.14. The rapid elasticity and early tension recovery resemble the response of a combination of two elastic components and one viscous component. Reasons are given for preferring an interpretation in terms of an undamped compliance in series with a damped compliance (Voigt element) rather than an undamped elasticity in parallel with a series combination of viscous and elastic components (Maxwell element).15. The rapid compliance does not correspond to the ;series elastic component' of two-component theories of muscle contraction.

Animals

Crinecerfont: emerging role in the management of congenital adrenal hyperplasia.

INTRODUCTION: Congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency is a rare genetic endocrine disorder characterized by impaired cortisol synthesis, excessive adrenal androgen production, and elevated adrenocorticotropic hormone (ACTH) concentrations. The current standard of care involves supraphysiologic doses of glucocorticoids to suppress ACTH and manage androgen excess, often leading to long-term complications. AREAS COVERED: A literature search of PubMed was conducted. This review critically examines the pharmacology, clinical efficacy, and potential role of crinecerfont in redefining CAH management. EXPERT OPINION: Crinecerfont, a selective corticotropin-releasing factor type 1 receptor (CRF1) antagonist, offers a novel therapeutic approach by targeting ACTH secretion at its hypothalamic origin. Recent Phase 2 and Phase 3 trials have demonstrated promising efficacy and safety across adult, adolescent, and pediatric populations. Crinecerfont may represent a promising adjunctive therapy in CAH management, addressing both biochemical control as well as quality of life and potentially long-term outcomes.

Humans

[Mushroom poisoning in childhood].

The authors describe frequency and importance of poisoning by Amanita phalloides. There are demonstrated the different toxins and their biochemical properties. The typical clinical symptoms of the intoxication by Amanita phalloides with vourse in two phases (1. gastrointestinal phase, 2. hepatonephrotic phase) are shown. The possibilities of diagnostic and differentialdiagnostic and the problems of therapy are discussed. It is pointed out, that in a modern treatment there must be given Penicillin-G-Natrium in high dosage as early as possible, also in cases of questionableness. Hemodialysis is only of effect till 40 hours after ingestion of Amanita.

Amanita