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Newest first. 5.2k questions across 107 tags.

5.2k questions · page 201 of 217

27 votes 3 answers29k views
How much protein in grams do I need at 74 kg on 900 kcal a day?

Stated plainly: 74 kg · 900 kcal. I have worked this out and I would like someone to find the error, because I suspect there is one. My working so far, for the…

protein-intake
protein-intake

Protein targets in grams per kilogram, per-meal distribution and the leucine threshold, and the evidence for a higher intake specifically during…

60 questions
nutrition
nutrition

Eating on a suppressed appetite: hitting nutritional targets inside a small energy budget, micronutrient risk, meal structure, and what the trial…

100 questions
lean-mass
lean-mass

Lean body mass as measured rather than assumed: what DEXA, BIA and air-displacement plethysmography each actually estimate, the body-composition…

127 questions
asked by dermot_kiely 12k · 2.2 years ago
2 votes 5 answers23k views
What does SURMOUNT-3 actually establish about a GLP-1 receptor agonist?

What I am working with: SURMOUNT-3 · a GLP-1 receptor agonist. I would like help reading this properly rather than being told what conclusion to reach. I have the…

clinical-trials
clinical-trials

Reading the primary literature properly: estimands, intention-to-treat versus per-protocol, confidence intervals, absolute versus relative…

745 questions
semaglutide
semaglutide

A GLP-1 receptor agonist with a fatty-acid-acylated backbone and a roughly one-week half-life, marketed for type 2 diabetes and for weight…

470 questions
cardiovascular
cardiovascular

Cardiovascular outcomes: the SELECT major-adverse-event result, SOUL, SUSTAIN 6 and REWIND, how to convert a hazard ratio into an absolute risk…

68 questions
asked by anouk_desmet 16k · 2.2 years ago
37 votes 5 answers33k views
Does a large published testing history at KP imply lot consistency?

This is my second independent submission on material from the same supplier. I suspect the usual explanation for this is wrong, or at least incomplete. I am aware…

batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

910 questions
vendor-vetting
vendor-vetting

Evaluating a supplier on evidence rather than reputation: testing history across batches, whether certificates are batch-specific, how failures…

454 questions
content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
asked by ahmed_zerouali 15k · 2.2 years ago
30 votes5 answers22k views
Does light exposure matter for a peptide in an amber vial?

I have continuous temperature data for the period in question, which is unusual and I would like to use it. I suspect the usual explanation for this is wrong, or at…

storage
storage

Storage conditions and their evidence base: minus twenty degrees for powder, refrigerated for solution, protection from light, and what the…

701 questions
peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 questions
shelf-life
shelf-life

How long a preparation remains within specification: labelled expiry for a sealed lyophilised vial, beyond-use dating after reconstitution, and…

327 questions
asked by hana_petrikova 10k · 2.2 years ago
24 votes0 answers23k views
Does vomiting at week three of tirzepatide usually resolve without a dose change?

For reference: vomiting · three · tirzepatide. I would like to understand the steps well enough to explain them to someone else. I have access to a refrigerator with…

vomiting
vomiting

Emesis as a reported adverse event: trial incidence, its relationship to dose escalation rate, dehydration risk, and when it stops being a…

57 questions
titration
titration

Stepwise dose increases over weeks, why the label schedules exist at all, and what tolerability-driven deviation from a schedule looks like in…

456 questions
tirzepatide
tirzepatide

A dual GIP and GLP-1 receptor agonist. Questions here cover the SURPASS and SURMOUNT programmes, the practical differences from a pure GLP-1…

370 questions
asked by coring_risk 27k · 2.2 years ago
35 votes5 answers67k views
Is a stablecoin transfer sensible for an order shipping to Ireland?

Conditions: a stablecoin transfer · Ireland. I would rather over-plan the first cycle and simplify later. I am prepared to do the work if someone can tell me which…

payment-privacy
payment-privacy

Payment mechanics and their privacy properties: why suppliers ask for stablecoin transfers, what an on-chain transfer reveals, confirmation…

31 questions
group-buy
group-buy

Pooled purchasing: how the economics work, what trust structure a pool needs, splitting a single tested lot, and the failure modes when the…

41 questions
international-shipping
international-shipping

Cross-border movement of research material: transit lanes and their thermal profiles, tracked versus untracked, declaration accuracy, and what…

471 questions
asked by jo_vandeberg 23k · 2.2 years ago
52 votes 3 answers35k views
Red, raised and itchy at the injection site for four days. How do I tell a local reaction from an infection?

Four days ago I injected into the left side of my abdomen. Within an hour there was a coin-sized red area, slightly raised, and it itched. It is now day four: the…

injection-site-reaction
injection-site-reaction

Local reactions: erythema, induration, pruritus and nodules. Their relationship to injection depth, diluent composition, benzyl alcohol…

49 questions
injection-technique
injection-technique

Technique questions: angle, pinch versus flat, aspiration, injection speed, air bubbles, and the handling steps that determine whether you deliver…

96 questions
subcutaneous
subcutaneous

Subcutaneous administration as a route: absorption kinetics from abdomen versus thigh versus upper arm, tissue depth, and why site rotation…

10 questions
sterility
sterility

Sterility as a test result rather than an adjective. Covers what a sterility test actually measures, why "sterile filtered" on a document is close…

142 questions
asked by linnea_wahlberg 17k · 2.2 years ago
35 votes 5 answers57k views
How comparable are a GLP-1 receptor agonist and cagrilintide on the evidence available?

What I have: a GLP-1 receptor agonist · cagrilintide. I have used one of these for a while and I am considering switching, which requires a reason. What I care about…

clinical-trials
clinical-trials

Reading the primary literature properly: estimands, intention-to-treat versus per-protocol, confidence intervals, absolute versus relative…

745 questions
semaglutide
semaglutide

A GLP-1 receptor agonist with a fatty-acid-acylated backbone and a roughly one-week half-life, marketed for type 2 diabetes and for weight…

470 questions
tirzepatide
tirzepatide

A dual GIP and GLP-1 receptor agonist. Questions here cover the SURPASS and SURMOUNT programmes, the practical differences from a pure GLP-1…

370 questions
amylin
amylin

Amylin and its analogues, most prominently cagrilintide, as a satiety mechanism orthogonal to incretin signalling. Includes the pharmacology of…

237 questions
asked by elke_brunner 17k · 2.2 years ago
9 votes5 answers18k views
How does cagrilintide behave on a C8 column compared to tirzepatide?

Details up front: cagrilintide · a C8 column · tirzepatide. I have used one of these for a while and I am considering switching, which requires a reason. What I care…

hplc
hplc

Reverse-phase high-performance liquid chromatography, the workhorse purity method. Column chemistry, mobile-phase choice, gradient slope,…

503 questions
purity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

833 questions
reference-standard
reference-standard

Certified reference materials and in-house standards: traceability, the certificate of the standard itself, system suitability, and why every…

185 questions
amylin
amylin

Amylin and its analogues, most prominently cagrilintide, as a satiety mechanism orthogonal to incretin signalling. Includes the pharmacology of…

237 questions
tirzepatide
tirzepatide

A dual GIP and GLP-1 receptor agonist. Questions here cover the SURPASS and SURMOUNT programmes, the practical differences from a pure GLP-1…

370 questions
asked by fib4_reader 24k · 2.2 years ago
25 votes 5 answers45k views
How comparable are semaglutide and survodutide on the evidence available?

Conditions: semaglutide · survodutide. These are treated as interchangeable and I do not think they are. If both are acceptable I would like to know that, so I can…

clinical-trials
clinical-trials

Reading the primary literature properly: estimands, intention-to-treat versus per-protocol, confidence intervals, absolute versus relative…

745 questions
semaglutide
semaglutide

A GLP-1 receptor agonist with a fatty-acid-acylated backbone and a roughly one-week half-life, marketed for type 2 diabetes and for weight…

470 questions
tirzepatide
tirzepatide

A dual GIP and GLP-1 receptor agonist. Questions here cover the SURPASS and SURMOUNT programmes, the practical differences from a pure GLP-1…

370 questions
survodutide
survodutide

A GLP-1 and glucagon receptor dual agonist with a substantial published MASH dataset. Use this tag for its hepatic endpoints, its dose ladder, and…

225 questions
asked by Dr_Jonas_Halvorsen 28k · 2.2 years ago
27 votes 4 answers50k views
What does REDEFINE-1 actually establish about cagrilintide?

The case in front of me: REDEFINE-1 · cagrilintide. The figures are clear enough; the question is what they mean and what they do not. I can supply the numbers if the…

clinical-trials
clinical-trials

Reading the primary literature properly: estimands, intention-to-treat versus per-protocol, confidence intervals, absolute versus relative…

745 questions
semaglutide
semaglutide

A GLP-1 receptor agonist with a fatty-acid-acylated backbone and a roughly one-week half-life, marketed for type 2 diabetes and for weight…

470 questions
cardiovascular
cardiovascular

Cardiovascular outcomes: the SELECT major-adverse-event result, SOUL, SUSTAIN 6 and REWIND, how to convert a hazard ratio into an absolute risk…

68 questions
amylin
amylin

Amylin and its analogues, most prominently cagrilintide, as a satiety mechanism orthogonal to incretin signalling. Includes the pharmacology of…

237 questions
asked by two_two_micron 9.3k · 2.2 years ago
11 votes0 answers6.7k views
Is a quantified content assay on one vial from a two-person split enough for the whole split?

The specifics, since they change the answer: a quantified content assay · a two-person split. I want to decide this in advance so that I am not deciding it under…

group-buy
group-buy

Pooled purchasing: how the economics work, what trust structure a pool needs, splitting a single tested lot, and the failure modes when the…

41 questions
batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

910 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

771 questions
content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
asked by gunnar_isaksen 14k · 2.2 years ago
13 votes 5 answers39k views
Is 4 °C an acceptable storage condition for lyophilised oral semaglutide?

Conditions: 4 °C · oral semaglutide. I want to know whether there is evidence behind this or only repetition. I have checked the obvious registries and monographs…

storage
storage

Storage conditions and their evidence base: minus twenty degrees for powder, refrigerated for solution, protection from light, and what the…

701 questions
peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 questions
shelf-life
shelf-life

How long a preparation remains within specification: labelled expiry for a sealed lyophilised vial, beyond-use dating after reconstitution, and…

327 questions
oral-glp1
oral-glp1

Oral routes for GLP-1 receptor agonism: peptide formulations rescued by absorption enhancers such as SNAC, and true small molecules that need no…

219 questions
asked by siobhan_deasy 9.5k · 2.2 years ago
36 votes 3 answers38k views
How much protein in grams do I need at 81 kg on 1,100 kcal a day?

The case in front of me: 81 kg · 1,100 kcal. I want the working, not the result — I need to be able to redo it with different numbers. I care about the precision as…

protein-intake
protein-intake

Protein targets in grams per kilogram, per-meal distribution and the leucine threshold, and the evidence for a higher intake specifically during…

60 questions
nutrition
nutrition

Eating on a suppressed appetite: hitting nutritional targets inside a small energy budget, micronutrient risk, meal structure, and what the trial…

100 questions
lean-mass
lean-mass

Lean body mass as measured rather than assumed: what DEXA, BIA and air-displacement plethysmography each actually estimate, the body-composition…

127 questions
asked by anouk_desmet 16k · 2.2 years ago
11 votes5 answers31k views
What does 98.8% purity on a C4 column actually tell me about a retatrutide vial?

Conditions: 98.8% · a C4 column · retatrutide. The figures are clear enough; the question is what they mean and what they do not. I can supply the numbers if the…

hplc
hplc

Reverse-phase high-performance liquid chromatography, the workhorse purity method. Column chemistry, mobile-phase choice, gradient slope,…

503 questions
purity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

833 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

771 questions
retatrutide
retatrutide

An investigational GLP-1, GIP and glucagon receptor tri-agonist, studied in the TRIUMPH programme. Not approved anywhere. Use this tag for…

251 questions
asked by eighty_six_hours 20k · 2.2 years ago
13 votes 5 answers19k views
How long does survodutide stay within specification at room temperature once reconstituted?

Details up front: survodutide · room temperature. I am trying to do this correctly the first time rather than learn it by getting it wrong. I have already made one…

peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 questions
storage
storage

Storage conditions and their evidence base: minus twenty degrees for powder, refrigerated for solution, protection from light, and what the…

701 questions
shelf-life
shelf-life

How long a preparation remains within specification: labelled expiry for a sealed lyophilised vial, beyond-use dating after reconstitution, and…

327 questions
survodutide
survodutide

A GLP-1 and glucagon receptor dual agonist with a substantial published MASH dataset. Use this tag for its hepatic endpoints, its dose ladder, and…

225 questions
asked by lukas_sedlacek 16k · 2.2 years ago
40 votes5 answers34k views
What is the thermal exposure on a Suzhou to Germany lane in summer?

Concretely: Suzhou · Germany. The figures are clear enough; the question is what they mean and what they do not. I can supply the numbers if the specifics change the…

cold-chain
cold-chain

Keeping material within a temperature window from manufacture to use: phase-change packs versus dry ice, thermal mass, transit-lane temperature…

578 questions
international-shipping
international-shipping

Cross-border movement of research material: transit lanes and their thermal profiles, tracked versus untracked, declaration accuracy, and what…

471 questions
storage
storage

Storage conditions and their evidence base: minus twenty degrees for powder, refrigerated for solution, protection from light, and what the…

701 questions
asked by noor_alhassan 11k · 2.2 years ago
36 votes 5 answers68k views
Does ecnoglutide adsorb measurably to the vial wall at 20 mg/mL?

The case in front of me: ecnoglutide · 20 mg/mL. I want the working, not the result — I need to be able to redo it with different numbers. I care about the precision…

peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

908 questions
content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
storage
storage

Storage conditions and their evidence base: minus twenty degrees for powder, refrigerated for solution, protection from light, and what the…

701 questions
ecnoglutide
ecnoglutide

A long-acting GLP-1 receptor agonist with a cAMP-biased signalling profile. A niche tag, mostly used for mechanism questions about biased agonism…

223 questions
asked by assay_blank 45k · 2.2 years ago
26 votes0 answers32k views
What does 99.1% purity on a wide-pore C18 column actually tell me about a mazdutide vial?

The specifics, since they change the answer: 99.1% · a wide-pore C18 column · mazdutide. I have the document in front of me and I can read the numbers. What I cannot…

hplc
hplc

Reverse-phase high-performance liquid chromatography, the workhorse purity method. Column chemistry, mobile-phase choice, gradient slope,…

503 questions
purity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

833 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

771 questions
mazdutide
mazdutide

A GLP-1 and glucagon receptor dual agonist developed primarily in China, with a distinct dose range and a fast-moving publication record.…

237 questions
asked by ahmed_zerouali 15k · 2.2 years ago
41 votes0 answers38k views
Is 98.4% a realistic purity ceiling for survodutide given its chain length?

For reference: 98.4% · survodutide. I would like the arithmetic checked rather than the conclusion asserted. I have deliberately not used an online calculator because…

purity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

833 questions
hplc
hplc

Reverse-phase high-performance liquid chromatography, the workhorse purity method. Column chemistry, mobile-phase choice, gradient slope,…

503 questions
peptide-mapping
peptide-mapping

Enzymatic digestion followed by LC-MS/MS to confirm sequence rather than just mass. The method that catches a scrambled sequence or a D-amino-acid…

103 questions
survodutide
survodutide

A GLP-1 and glucagon receptor dual agonist with a substantial published MASH dataset. Use this tag for its hepatic endpoints, its dose ladder, and…

225 questions
asked by rae_oyelowo 17k · 2.2 years ago
23 votes5 answers47k views
How long does a Xianning to Spain lane usually take with tracking?

What I am working with: Xianning · Spain. I have read the primary source rather than the summary, which has left me with more questions. I understand the headline. I…

international-shipping
international-shipping

Cross-border movement of research material: transit lanes and their thermal profiles, tracked versus untracked, declaration accuracy, and what…

471 questions
customs
customs

Customs handling: how declarations are assessed, why a parcel sits at a facility for a week, seizure notices, and the practical difference between…

196 questions
cold-chain
cold-chain

Keeping material within a temperature window from manufacture to use: phase-change packs versus dry ice, thermal mass, transit-lane temperature…

578 questions
asked by ahmed_zerouali 15k · 2.2 years ago
13 votes4 answers16k views
Is 1 mg/mL a sensible working concentration for cagrilintide, or should I go lower?

What I am working with: 1 mg/mL · cagrilintide. I suspect the honest answer is that it depends, in which case I would like to know on what. Assume I can obtain either…

diluent-volume
diluent-volume

Choosing how much diluent to add, which is really a question about what you want your measurement resolution to be. Larger volumes buy you…

295 questions
reconstitution
reconstitution

Taking a lyophilised vial to a solution of known concentration: choice of diluent, volume selection, how to add liquid without shearing the cake,…

313 questions
dosing-math
dosing-math

The arithmetic itself: milligrams to millilitres to insulin units, concentration after reconstitution, dose per draw, and vial-days per vial. Show…

764 questions
amylin
amylin

Amylin and its analogues, most prominently cagrilintide, as a satiety mechanism orthogonal to incretin signalling. Includes the pharmacology of…

237 questions
asked by anja_hellstrom 13k · 2.2 years ago
20 votes0 answers22k views
Why does my content assay disagree with the label by more than purity would allow?

The method section is present, which is unusual enough that I want to make use of it. I noticed this today and I have not touched anything since, in case the state is…

content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

476 questions
purity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

833 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

771 questions
asked by pieter_maas 14k · 2.2 years ago
40 votes 5 answers60k views
What does Medutest verification of Shanghai Sigma-Audley actually cover?

What I have: Medutest · Shanghai Sigma-Audley. I have read the primary source rather than the summary, which has left me with more questions. I understand the…

vendor-investigate
vendor-investigate

VendorInvestigate, an independent vendor review and verification service. Use this tag for questions about its verification criteria, what a…

113 questions
vendor-vetting
vendor-vetting

Evaluating a supplier on evidence rather than reputation: testing history across batches, whether certificates are batch-specific, how failures…

454 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

771 questions
medutest
medutest

Medutest, one of four independent testing and verification services referenced throughout this site. Use this tag for its methods, its report…

126 questions
asked by ravenna_pace 14k · 2.2 years ago