c.bakker

TL2 Moderator · Basel

Contributes reviews on supplier material. Based in Basel.

Joined 9 January 2025 · last posted 2d

89 posts, newest first. Showing up to 150.

Revisiting: What pooling buys you and what it destroys Replied, post #107 · Evidence › Meta-analyses · 26 Jul 2026 · 24 likes Inclusion and exclusion criteria: a meta-analysis is only as good as its inclusion criteria. If the criteria are too broad, apples and oranges get pooled. If they are…
Second pass at: Sleep apnoea improving and the equipment implications Replied, post #91 · Wellbeing › Sleep · 21 Jul 2026 · 0 likes Worth separating two things that post #87 runs together. Sleep apnoea improvement: as weight is lost, sleep apnoea usually improves. The timeframe is weeks to months,…
What a certificate commits its issuer to Replied, post #59 · Analytics › COA interpretation · 19 Jul 2026 · 17 likes Purity and content are different measurements: purity tells you what proportion of the detected material is the intended species. Content tells you how much of the…
[2026 update] Waist circumference technique and its repeatability Replied, post #25 · Outcomes › Progress reports · 16 Jul 2026 · 5 likes Protein intake and resistance training: both self-reported and therefore optimistic in most reports. Recording them anyway creates a record you can look back on.
What a reversed-phase purity number actually is Replied, post #49 · Analytics › HPLC & UHPLC · 13 Jul 2026 · 19 likes Method validation is the demonstration that a method can separate the compound from its degradation products and impurities reliably. A method that cannot resolve an…
Publication patterns in the BPC-157 literature, examined Replied, post #30 · Compounds › Repair & healing peptides · 7 Jul 2026 · 0 likes Oral versus injected administration claims for BPC-157: the preclinical work studied injection. Oral claims are common in supplier marketing and poorly supported by…
Semaglutide and gastric emptying — the mechanism behind most of the side-effect profile Replied, post #94 · Compounds › Semaglutide · 7 Jul 2026 · 12 likes Approved indications differ by jurisdiction and change. As of mid-2026 the weight-management indication is approved in many European jurisdictions but not all, and…
Specificity, linearity, accuracy, precision, range, robustness — with real criteria Replied, post #39 · Analytics › Method validation · 5 Jul 2026 · 1 like System suitability: injections run at the start of a batch to establish that the instrument and column are performing. Acceptance criteria typically include replicate…
Why retatrutide discussion here is more cautious than elsewhere — one year on Replied, post #28 · Compounds › Retatrutide · 30 Jun 2026 · 4 likes Phase 2 sample sizes are not adequate for safety characterisation of a novel triple agonist. Phase 3 is where that question gets answered. Using phase 2 results to make…
Secretagogues and glucose tolerance: the mechanistic concern Replied, post #52 · Compounds › Secretagogues & GH axis · 27 Jun 2026 · 15 likes post #51 is right about the mechanism and I think understates the practical bit. CJC-1295 with and without DAC: the version with a drug affinity complex binds albumin…
Submitting a sample: the process end to end Replied, post #27 · Sourcing › Independent verification · 20 Jun 2026 · 1 like Blind sampling: submitting without the laboratory or seller knowing the source removes the two easiest ways for a result to be shaped: selective submission and…
Manufacturer assistance programmes and their eligibility rules Replied, post #34 · Access › Pricing · 15 Jun 2026 · 2 likes Biosimilars and future generics: as patents expire, biosimilar and generic versions might become available and prices might fall. That has already happened for some…
Racemisation and why it is invisible to a mass measurement Replied, post #30 · Analytics › Impurities & related substances · 10 Jun 2026 · 0 likes I read post #28 twice before replying, because I had assumed the opposite. Aggregates: multiples of the monomer mass. May not elute at all under a standard…
Revisiting: What pooling buys you and what it destroys Replied, post #42 · Evidence › Meta-analyses · 3 Jun 2026 · 3 likes Coming back to post #40, because the follow-up matters more than the original answer. Publication bias: what did not get published? Small studies with negative results…
Personal or family history of medullary thyroid carcinoma — what changed since Replied, post #39 · Safety › Contraindications · 15 May 2026 · 9 likes Worth separating two things that post #35 runs together. History of pancreatitis: these compounds can rarely trigger pancreatitis. History of pancreatitis increases…
Injection volume, overload, and peak distortion Replied, post #4 · Analytics › HPLC & UHPLC · 11 May 2026 · 27 likes I read the opening post twice before replying, because I had assumed the opposite. Two things before anyone answers the substance. First, the context in the first post…
When a dose reduction is the correct response to a side effect Replied, post #19 · Practice › Dosing & titration · 10 May 2026 · 1 like The arithmetic of an intermediate dose: if the label says 1.0 mg and 2.0 mg, a dose strictly between them is off-label by definition. Some people compute it anyway. The…
Transporting a vial for a weekend away — a second dataset Replied, post #19 · Practice › Storage & stability · 2 Apr 2026 · 6 likes For anyone arriving from a search: the marked solution above is the direct answer, and the replies underneath it add the caveats that make it safe to use.
Residual solvents and scavengers: what is looked for — what changed since Replied, post #21 · Analytics › Impurities & related substances · 28 Mar 2026 · 19 likes Incomplete deprotection: mass higher by the protecting group mass. Usually markedly later eluting. A synthesis artifact from incomplete removal of protecting groups.
Introducing myself: pharmacist, sceptic, reluctant participant — one year on Replied, post #74 · Lounge › Introductions · 15 Mar 2026 · 21 likes Picking up post #71: that is the part I would want checked first. No judgment: people come to this community from all backgrounds and with all motivations.…
Which fields on a certificate actually matter, ranked Replied, post #4 · Analytics › COA interpretation · 10 Mar 2026 · 0 likes When method identifiers are missing: "reversed-phase HPLC" is less specific than "reversed-phase HPLC at 214 nm on a C18 column with a 10 to 40% acetonitrile gradient…
Reading a preclinical wound-healing model and its relevance to a human tendon — a second… Replied, post #24 · Compounds › Repair & healing peptides · 10 Mar 2026 · 4 likes I disagree with the reply above, and I think the disagreement is substantive rather than terminological. The distinction being drawn does not survive when you look at…
Why the titration planner refuses to produce a schedule below a floor Replied, post #44 · Data & Tools › Calculators · 28 Feb 2026 · 11 likes Reconstitution calculator: enter vial mass, final volume target, and the calculator tells you concentration and syringe mark for a given dose. Useful for…
The most common factual error about semaglutide on the internet — what changed since Replied, post #37 · Compounds › Semaglutide · 27 Feb 2026 · 0 likes This follows post #34 rather than contradicting it. Albumin binding is not a unique structural feature and nothing in the class lacks it, but the reversibility matters.…
Second pass at: Identical chromatograms across two different lots Replied, post #30 · Sourcing › Red flags · 27 Feb 2026 · 7 likes Coming back to post #28, because the follow-up matters more than the original answer. Inconsistency across documents: a certificate stating one purity, a website…
Pinch or no pinch, and how needle length changes the answer — the long version Replied, post #24 · Practice › Administration · 26 Feb 2026 · 0 likes Having read the exchange above, I think I was wrong earlier in this topic and I want to say so plainly rather than quietly editing. The correction was fair and I had…
Measurement error in a self-reported exposure Replied, post #59 · Evidence › Study critique · 24 Feb 2026 · 24 likes Coming back to post #57, because the follow-up matters more than the original answer. Two things before anyone answers the substance. First, the context in the first…
Seven-day rolling means and why weekly readings mislead — one year on Replied, post #66 · Outcomes › Progress reports · 16 Feb 2026 · 0 likes Worth separating two things that post #62 runs together. Non-scale victories: muscle gain or maintenance, clothing fit, energy level, and capability (like climbing…
IGF-1 as a surrogate endpoint and its limitations Replied, post #8 · Compounds › Secretagogues & GH axis · 16 Feb 2026 · 1 like This follows post #5 rather than contradicting it. Development history is more informative than speculation: ipamorelin was investigated clinically for post-operative…
Citation sweep results: how many references did not say what was claimed Replied, post #40 · Meta › Wiki maintenance · 3 Feb 2026 · 30 likes Authority: if you think a page needs input from someone with specific expertise, suggesting that person helps the maintainer recruit contributors.
Why catalogue breadth is not evidence of anything Started this topic · Compounds › Other compounds · 21 Jan 2026 · 9 likes Why catalogue breadth is not evidence of anything I have a specific reason for asking rather than idle curiosity, and the context is below. I have seen SURPASS-4 (…
Distinguishing expected GI effects from something that needs urgent attention Replied, post #87 · Practice › Side effects · 13 Jan 2026 · 9 likes Lean mass loss: the rate of lean tissue loss depends on protein intake, resistance training volume, and total energy deficit. Adequate protein and maintaining training…
Injection discomfort: needle gauge, volume, temperature, technique Replied, post #12 · Practice › Administration · 6 Jan 2026 · 0 likes I read post #10 twice before replying, because I had assumed the opposite. Having read the exchange above, I think I was wrong earlier in this topic and I want to say…
Filter needles: when they help and what they cost you Replied, post #19 · Devices › Syringes & needles · 5 Jan 2026 · 0 likes On post #15 — agreed on the reasoning, with one qualification. Insulin syringe graduations: U-100 syringes are marked in units where 100 units = 1 mL. Always confirm…
Prescription requirements and telehealth models Replied, post #93 · Sourcing › Regulatory · 26 Dec 2025 · 31 likes This follows post #90 rather than contradicting it. For anyone arriving from a search: the marked solution above is the direct answer, and the replies underneath it add…
Specificity, linearity, accuracy, precision, range, robustness — with real criteria — a… Replied, post #49 · Analytics › Method validation · 22 Dec 2025 · 21 likes Why two laboratories may disagree: after validating the same method, they may still report different purity on the same sample due to integration differences, column…
Price changes over 2025 and 2026, tabulated and dated — does this still hold? Replied, post #39 · Access › Pricing · 17 Dec 2025 · 5 likes Biosimilars and future generics: as patents expire, biosimilar and generic versions might become available and prices might fall. That has already happened for some…
Tracking that stops updating and then resumes — the long version Replied, post #51 · Sourcing › Logistics · 14 Dec 2025 · 0 likes This follows post #48 rather than contradicting it. Reshipment after seizure: if a parcel is seized, some suppliers will reship; others will not. That is a supplier…
Retatrutide's phase 2 heart-rate signal and how to think about it Replied, post #17 · Compounds › Retatrutide · 3 Dec 2025 · 7 likes Glucagon receptor agonism seems paradoxical in a weight-loss compound because glucagon raises blood glucose. The paradox resolves because glucagon agonism also…
Coming back to: Feature request: should a dose-equivalence tool exist at all? Replied, post #19 · Data & Tools › Calculators · 26 Nov 2025 · 18 likes post #18 answers the question as asked. The question underneath it is different. Dose equivalence calculator: compounds have different potencies. The calculator is…
Detection wavelength and why 214 nm and 280 nm disagree Replied, post #81 · Analytics › HPLC & UHPLC · 13 Nov 2025 · 2 likes Peak purity: a diode-array detector records a spectrum at every time point. If a peak contains two co-eluting species with different spectra, the spectrum changes…
Shoulders, tangent skims, and defensible integration — the long version Replied, post #2 · Analytics › HPLC & UHPLC · 11 Nov 2025 · 2 likes Before anything else: what was the gradient, and at what wavelength? Area percent at different wavelengths is not the same number even on the same sample because…
Oral versus injectable exposure: comparing apples to a different fruit Replied, post #3 · Compounds › Oral incretins · 28 Oct 2025 · 0 likes Two things before anyone answers the substance. First, the context in the first post is clear and specific. Second, the question is framed so that an answer can…
Reading SURMOUNT-1 without the press release Replied, post #41 · Compounds › Tirzepatide · 22 Oct 2025 · 10 likes post #40 answers the question as asked. The question underneath it is different. The GIP component: GIP receptor agonism is thought to amplify the GLP-1 effect on…
How to read a phase 2 result without treating it as a phase 3 result — what changed since Replied, post #9 · Compounds › Retatrutide · 12 Oct 2025 · 0 likes Hepatic effects: glucagon receptor agonism promotes hepatic fat oxidation, which is mechanistically plausible for benefit in metabolic liver disease. Whether that…
Coming back to: Where the integrator drew the baseline, and how much it moved the number Replied, post #8 · Analytics › HPLC & UHPLC · 22 Sep 2025 · 21 likes Peak purity: a diode-array detector records a spectrum at every time point. If a peak contains two co-eluting species with different spectra, the spectrum changes…
Follow-up: Why the titration planner refuses to produce a schedule below a floor Replied, post #119 · Data & Tools › Calculators · 17 Sep 2025 · 17 likes Reconstitution calculator: enter vial mass, final volume target, and the calculator tells you concentration and syringe mark for a given dose. Useful for…
Reverse causation in a cohort study of weight and outcome — a second dataset Replied, post #65 · Evidence › Study critique · 14 Sep 2025 · 0 likes Multiple comparisons: if a paper reports many outcomes, the chance of a spurious association by random chance is real. Pre-specification of primary outcomes matters and…
Titles that describe the question, not the situation — what changed since Replied, post #7 · Start Here › How to Ask · 10 Sep 2025 · 24 likes Context that matters: compound, how long in, current dose, relevant history. Context that does not matter: how you feel, your hopes for the outcome, your medical…
When a tidy document is a signal and when it is decoration — does this still hold? Replied, post #6 · Analytics › COA interpretation · 24 Aug 2025 · 4 likes Coming back to post #4, because the follow-up matters more than the original answer. Practical note that does not fit anywhere else. Whatever you conclude from this…
Meeting a protein target on a suppressed appetite Replied, post #17 · Nutrition & Training › Protein & intake · 23 Aug 2025 · 0 likes This follows post #14 rather than contradicting it. Eating anything at all: on substantial appetite suppression, eating enough total calories to maintain lean mass is…
Power cut for eleven hours: how I assessed it afterwards Replied, post #31 · Practice › Storage & stability · 22 Aug 2025 · 18 likes Protecting from light: amber vials or opaque containers reduce light exposure. If you are storing for long periods and light matters, this is worth doing. For…
Hypertension improvement and when medication needs revisiting Replied, post #16 · Clinical › Comorbidities · 20 Aug 2025 · 3 likes Worth separating two things that post #12 runs together. Having read the exchange above, I think I was wrong earlier in this topic and I want to say so plainly rather…
When a preprint is the best available evidence and we say so Replied, post #55 · Evidence › Preprints · 14 Aug 2025 · 10 likes I read post #53 twice before replying, because I had assumed the opposite. Server repositories: medRxiv for medicine, bioRxiv for biology. Preprints on these servers…
BPC-157: what the rodent literature actually shows, and what it does not — a second… Replied, post #83 · Compounds › Repair & healing peptides · 13 Aug 2025 · 2 likes post #82 is right about the mechanism and I think understates the practical bit. Stability of BPC-157 in solution: what has been measured in published work covers…
How to research a compound with no human data without deceiving yourself Replied, post #107 · Compounds › Other compounds · 4 Aug 2025 · 23 likes Worth separating two things that post #103 runs together. Sequence verification: for an obscure compound, a report of the amino acid sequence or a mass-spectrometry…
Coming back to: Sample size calculations, read backwards from the published number Replied, post #59 · Evidence › Trials · 19 Jul 2025 · 0 likes On post #55 — agreed on the reasoning, with one qualification. Absolute numbers, not just relative: a 30% relative reduction tells you the ratio but not the practical…
Coming back to: Amylin analogue mechanism: satiety signalling separate from GLP-1 Replied, post #8 · Compounds › Cagrilintide & amylin analogues · 18 Jul 2025 · 12 likes On post #4 — agreed on the reasoning, with one qualification. The dosing interval: cagrilintide's half-life is roughly 7 to 8 days, suitable for weekly dosing. The…
Angle of injection and whether 90 degrees is always right Started this topic · Practice › Administration · 10 Jul 2025 · 8 likes On the subject in the title: Angle of injection and whether 90 degrees is always right Working notes rather than a conclusion. Reporting something rather than asking…
Repeatability versus intermediate precision Replied, post #121 · Analytics › Method validation · 2 Jul 2025 · 0 likes Accuracy: the method measures what you intend to measure. For purity methods, this is tested by spike-and-recover experiments: add a known amount of impurity to a…
TB-500 and thymosin beta-4: the fragment versus the protein Replied, post #51 · Compounds › Repair & healing peptides · 26 Jun 2025 · 17 likes post #50 answers the question as asked. The question underneath it is different. Analytical identity of BPC-157: a 15-residue peptide with an unambiguous mass (≈1419.5…
Coming back to: Semaglutide half-life: where the 165 to 184 hour figure comes from Replied, post #41 · Compounds › Semaglutide · 25 Jun 2025 · 0 likes Is there a ceiling dose beyond which the effect plateaus? The trials did not study that because they stopped at 2.4 mg. Some people report trying higher doses, but…
Journal club: SURMOUNT-1, read without the press release Replied, post #142 · Evidence › Journal club · 21 Jun 2025 · 10 likes SURMOUNT-OSA (N Engl J Med 2024): Tirzepatide in obstructive sleep apnoea, using an objective physiological endpoint. Notable because soft endpoints are avoided. Two…
Reading an MS report that only gives you a single number Replied, post #110 · Analytics › Mass spectrometry · 17 Jun 2025 · 0 likes Purity and identity are different questions: LC-MS establishes that the species at a retention time has the expected mass. It does not establish how much of the sample…
Revisiting: Why a compound being unapproved is not the same as being illegal to possess Replied, post #11 · Sourcing › Regulatory · 25 May 2025 · 0 likes Regulatory positions change: a compound's status today might differ from its status a year from now. Citing a regulatory position is worth doing only with a date…
Which panel is worth repeating and which is worth ignoring Replied, post #12 · Clinical › Bloodwork · 2 May 2025 · 26 likes Reference intervals: constructed to contain the central 95% of a reference population, which means one in twenty healthy people falls outside one by definition. Add…
Splitting a vial for two laboratories: how to do it without ruining both Replied, post #27 · Sourcing › Independent verification · 26 Apr 2025 · 2 likes Repeat testing: if you want to verify the same lot a second time, testing with a different service strengthens the conclusion. Testing with the same service verifies…
Dizziness on standing: the ordinary explanation first Replied, post #9 · Nutrition & Training › Hydration & electrolytes · 24 Apr 2025 · 0 likes Lab testing: if symptoms are severe or persistent, checking electrolytes and minerals (sodium, potassium, magnesium, calcium) and interpreting them in context of losses…
Why fasting instructions for oral semaglutide are not optional advice — does this still… Replied, post #21 · Compounds › Oral incretins · 21 Apr 2025 · 17 likes Why an oral formulation is a formulation achievement: the molecule is the same but the tablet is novel. Getting a peptide across the gastric epithelium at usable…
Obstructive sleep apnoea and a hard endpoint in this class Replied, post #56 · Clinical › Comorbidities · 12 Apr 2025 · 0 likes post #55 is right about the mechanism and I think understates the practical bit. Obstructive sleep apnoea: SURMOUNT-OSA used an objective endpoint, the apnoea-hypopnoea…
Adducts: sodium, potassium, and the peak you did not expect Replied, post #58 · Analytics › Mass spectrometry · 6 Apr 2025 · 15 likes Resolution: "high resolution" commonly means
Follow-up: Tesamorelin has an approved indication — what that changes about the evidence Replied, post #37 · Compounds › Secretagogues & GH axis · 5 Apr 2025 · 9 likes I read post #35 twice before replying, because I had assumed the opposite. GHRH analogues versus ghrelin mimetics are often conflated but they are different mechanisms.…
Maintainer handover: how it works Replied, post #41 · Meta › Wiki maintenance · 16 Mar 2025 · 21 likes This follows post #38 rather than contradicting it. Cross-referencing: if two pages should reference each other but do not, suggesting the cross-reference helps the…
Journal club: SUSTAIN 6 and its retinopathy signal — does this still hold? Replied, post #56 · Evidence › Journal club · 14 Mar 2025 · 0 likes I read post #54 twice before replying, because I had assumed the opposite. SOUL (N Engl J Med 2025): Oral semaglutide cardiovascular outcomes. Extends the…
Coverage for the indication versus for the drug — a second dataset Replied, post #12 · Access › Insurance & coverage · 11 Mar 2025 · 11 likes Generic versus brand: most of these compounds do not have generic versions yet. Once they do, formulary coverage and pricing will shift.
Revisiting: Bug report: the reconstitution calculator and a rounding edge case Replied, post #114 · Data & Tools › Calculators · 4 Mar 2025 · 17 likes Dose equivalence calculator: compounds have different potencies. The calculator is provided with a caveat: "equivalence" is not precise and individual response varies.…
The CagriSema phase 2 paper and what a fixed combination buys Replied, post #5 · Compounds › Cagrilintide & amylin analogues · 27 Jan 2025 · 0 likes Gastric emptying: both amylin and GLP-1 slow it, through partly overlapping but distinct mechanisms. Whether the slowing at a higher magnitude produces disproportionate…
Follow-up: Tirzepatide's shorter half-life and its one practical consequence Replied, post #138 · Compounds › Tirzepatide · 9 Jan 2025 · 2 likes Picking up post #135: that is the part I would want checked first. SURMOUNT-1 reported weight reduction of a magnitude that was the largest for a pharmacological…
Second pass at: A field-by-field walk through a certificate of analysis Replied, post #148 · Analytics › COA interpretation · 11 Dec 2024 · 21 likes Counter-ion form is crucial: peptides are isolated as salts, most often trifluoroacetate from reversed-phase purification or acetate after salt exchange. The…
Revisiting: Moderation log format change Replied, post #55 · Meta › Announcements · 5 Dec 2024 · 11 likes post #54 is right about the mechanism and I think understates the practical bit. Implementation timeline: announcements include when a change takes effect. Marking the…
Identical chromatograms across two different lots Replied, post #49 · Sourcing › Red flags · 14 Nov 2024 · 0 likes Inability to trace lots: if you ask "where was this synthesised, by whom, under what conditions" and cannot get a clear answer, that is a red flag. Traceability is not…
Time to steady state after a dose increase Replied, post #108 · Pharmacology › Pharmacokinetics · 5 Nov 2024 · 5 likes post #107 answers the question as asked. The question underneath it is different. Thank you for the correction. I have edited my earlier post with a note rather than…
Second pass at: Buffers, pH and why a formulation is a formulation Replied, post #23 · Pharmacology › Formulation chemistry · 27 Oct 2024 · 15 likes Two things before anyone answers the substance. First, the context in the first post is clear and specific. Second, the question is framed so that an answer can…
Progressive overload when the scale is falling — one year on Replied, post #112 · Nutrition & Training › Resistance training · 1 Oct 2024 · 0 likes Recovery: heavier training on a energy deficit and on a compound that slows gastric emptying requires attention to recovery (sleep, nutrition, stress). Recovery…
Revisiting: How to bring a laboratory report to an appointment usefully Replied, post #24 · Clinical › Bloodwork · 12 Sep 2024 · 0 likes Thank you for the correction. I have edited my earlier post with a note rather than silently, so the thread still makes sense to read. The error was mine and it was the…
[2026 update] People with a low starting BMI: where the evidence stops Replied, post #14 · Clinical › Special populations · 3 Sep 2024 · 7 likes Coming back to post #12, because the follow-up matters more than the original answer. Adolescents: a distinct evidence base exists. The compounds are not approved for…
Correlation in a self-tracked dataset: what it can support Replied, post #85 · Research Methods › Statistics · 23 Aug 2024 · 4 likes Two things before anyone answers the substance. First, the context in the first post is clear and specific. Second, the question is framed so that an answer can…
Splitting a vial for two laboratories: how to do it without ruining both — what changed… Replied, post #4 · Sourcing › Independent verification · 17 Aug 2024 · 0 likes Blind sampling: submitting without the laboratory or seller knowing the source removes the two easiest ways for a result to be shaped: selective submission and…
Coming back to: Purity assay versus content assay: two different numbers Replied, post #30 · Analytics › COA interpretation · 10 Aug 2024 · 0 likes When method identifiers are missing: "reversed-phase HPLC" is less specific than "reversed-phase HPLC at 214 nm on a C18 column with a 10 to 40% acetonitrile gradient…