{
  "vercy": "1.0-draft",
  "publication": {
    "status": "research-draft",
    "adjudicationStatus": "unreviewed",
    "publishableCanonical": false,
    "generatedAt": "2026-09-12T11:18:33Z",
    "providers": [
      "Codex"
    ],
    "breadth": "recalled by Codex without web access - no source was read",
    "missingProviders": [],
    "pass": 2,
    "cost": {
      "grok": {
        "seconds": 23.0,
        "error": "Reading additional input from stdin...\nOpenAI Codex v0.153.4\n--------\nworkdir: R:\\02_PROJECTS\\02_Meta_Models_Platforms\\Ver.cy\\current\\thing-registry-backlog\nmodel: gpt-6-astra\nprovider: openai\napproval: never\nsandbox: read-only\nreasoning effort: none\nreasoning summaries: none\nsession id: 01a09555-eb11-7a22-bbef-195079ef0469\n--------\nuser\nDescribe what is already known about one registered thing. Answer as JSON only, no prose around it.\n\nThing: methylnaltrexone bromide\nSense to describe: (none recorded)\nDomain code: PHY.MAT\nAlso known as: (none)\n\n\nContext for this batch of 1001 things:\n# Batch ",
        "usd": 0.0,
        "recall": true
      },
      "codex": {
        "seconds": 84.7,
        "error": "Reading additional input from stdin...\nOpenAI Codex v0.153.4\n--------\nworkdir: R:\\02_PROJECTS\\02_Meta_Models_Platforms\\Ver.cy\\current\\thing-registry-backlog\nmodel: gpt-6-astra\nprovider: openai\napproval: never\nsandbox: read-only\nreasoning effort: none\nreasoning summaries: none\nsession id: 01a09555-ead6-7451-9b8b-6f99c875d07a\n--------\nuser\nYou are drafting a Vercy meta-model for one registered thing. Answer as JSON only, no prose around it.\n\nThing: methylnaltrexone bromide\nRegistry id: vr.tr.methylnaltrexone-bromide\nPlane / domain: PHY / PHY.MAT\nRegistry definition: (none recorded)\nNames folded "
      }
    },
    "enrichment": {
      "pass": 3,
      "engine": "claude",
      "producedAt": "2026-10-06T12:00:00Z",
      "ingestedAt": "2026-10-06T08:56:41+00:00",
      "fields": [
        "agent_conduct",
        "ethics",
        "failure_modes_and_hazards",
        "owners",
        "visual_identification"
      ]
    },
    "gate": {
      "passed": true,
      "version": "1.0",
      "at": "2026-10-07T10:10:31+00:00",
      "evidence": [
        "completeness 1.00",
        "sense: Wikidata description",
        "2 live sources",
        "review by codex: pass"
      ]
    }
  },
  "metaModel": {
    "id": "THING-Q59904170",
    "registryId": "vr.tr.methylnaltrexone-bromide",
    "name": "methylnaltrexone bromide",
    "version": "0.1.0-research.1",
    "entryKind": "thing",
    "family": "Thing Registry",
    "domain": [
      "PHY.MAT"
    ],
    "status": "research-draft"
  },
  "canonicalUrl": "https://ver.cy/models/thing/q59904170/",
  "model": {
    "registry_id": "vr.tr.methylnaltrexone-bromide",
    "name": "methylnaltrexone bromide",
    "purpose": "Enable an AI agent to recognise methylnaltrexone bromide, assess a material lot's identity and fitness, and determine which handling or downstream-use decisions require further evidence.",
    "definition": "Methylnaltrexone bromide is the bromide salt of methylnaltrexone, a quaternary ammonium derivative of naltrexone that antagonizes peripheral μ-opioid receptors and is used to treat opioid-induced constipation.",
    "scope_statement": "This model owns the chemical substance registered as vr.tr.methylnaltrexone-bromide in PHY / PHY.MAT, including its stereochemical salt identity, composition, material state, quality, pharmacological relationships and substance-level restrictions.",
    "in_scope": [
      "Methylnaltrexone cation identity, stereochemistry and bromide counterion",
      "Salt content, assay basis, impurities and material grade",
      "Solid or dissolved state and condition-dependent physical properties",
      "Lot provenance, analytical evidence and stability status",
      "Relationships to opioid receptor antagonism and medicinal products",
      "Substance-specific handling hazards and jurisdictional identifiers"
    ],
    "out_of_scope": [
      "Finished RELISTOR tablets, injections, excipients and delivery devices",
      "Patient-specific prescribing, dosing and treatment monitoring",
      "Opioid-induced constipation as a disease or treatment pathway",
      "Manufacturing equipment and synthesis process execution",
      "Naltrexone, other opioid antagonists and methylnaltrexone metabolites as independent substances"
    ],
    "distinguishing_features": [
      "Verify the bromide salt rather than identifying only the methylnaltrexone cation; PubChem distinguishes salt CID 5361917 from cation CID 5361918. [PubChem salt record](https://pubchem.ncbi.nlm.nih.gov/compound/5361917), [PubChem cation record](https://pubchem.ncbi.nlm.nih.gov/compound/Methylnaltrexone).",
      "Check the quaternary nitrogen and stereochemical structure against an authenticated methylnaltrexone bromide reference; a name containing naltrexone is insufficient. [RELISTOR prescribing information](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=c488fb7c-0a5b-487c-b452-996809d1cb99).",
      "Check compatibility with formula C21H26BrNO4 and formula mass 436.36 g/mol, while recognising that these alone do not distinguish stereoisomers. [RELISTOR prescribing information](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=c488fb7c-0a5b-487c-b452-996809d1cb99).",
      "Distinguish an identified bulk substance from a formulated medicine by checking excipients, presentation and lot documentation."
    ],
    "characteristics": [
      {
        "name": "Stereochemical salt identity",
        "kind": "category",
        "unit_or_values": "Authenticated structure, stereochemical identifier and bromide counterion",
        "why_it_matters": "Prevents substitution of a related antagonist, isolated cation or stereoisomer."
      },
      {
        "name": "Assay and reporting basis",
        "kind": "measurement",
        "unit_or_values": "% w/w; as received, dried or anhydrous; bromide salt or cation equivalent",
        "why_it_matters": "Amounts cannot be compared reliably when water correction or chemical basis differs."
      },
      {
        "name": "Bromide stoichiometry",
        "kind": "measurement",
        "unit_or_values": "mol bromide/mol methylnaltrexone cation",
        "why_it_matters": "Tests salt composition alongside cation identity."
      },
      {
        "name": "Related substances and stereoisomer content",
        "kind": "measurement",
        "unit_or_values": "% by validated method, with response factors and reporting limits",
        "why_it_matters": "Separates chemical assay from stereochemical and impurity quality."
      },
      {
        "name": "Water and residual solvents",
        "kind": "measurement",
        "unit_or_values": "Water % w/w; individual solvents ppm or mg/kg",
        "why_it_matters": "Supports composition correction and suitability assessment."
      },
      {
        "name": "Material state",
        "kind": "state",
        "unit_or_values": "Solid or solution; identified solid form; temperature, humidity and solvent context",
        "why_it_matters": "Physical state affects sampling, storage and processing."
      },
      {
        "name": "Solubility and thermal behaviour",
        "kind": "measurement",
        "unit_or_values": "Solubility in mg/mL with solvent, pH and temperature; thermal events in °C with method",
        "why_it_matters": "Prevents unsupported dissolution assumptions and confusion between melting and decomposition."
      },
      {
        "name": "Material grade and disposition",
        "kind": "state",
        "unit_or_values": "Declared grade; quarantined, released, rejected or awaiting retest against a named specification",
        "why_it_matters": "Chemical identity alone does not establish fitness for pharmaceutical use."
      },
      {
        "name": "Pharmacological relationship",
        "kind": "relation",
        "unit_or_values": "Methylnaltrexone moiety to peripheral mu-opioid receptor antagonism",
        "why_it_matters": "Connects the substance to its biological role without making a prescribing decision."
      },
      {
        "name": "Hazard and regulatory evidence",
        "kind": "relation",
        "unit_or_values": "Applicable SDS, identifier records, jurisdiction, revision date and exposure-limit evidence",
        "why_it_matters": "Makes handling and permitted-use decisions traceable to applicable documents."
      }
    ],
    "affordances": [
      "Match a supplier lot to the registered substance using structural, counterion and analytical evidence.",
      "Compare assay results after reconciling salt, cation and water-content bases.",
      "Assess a lot against a specified research or pharmaceutical material specification.",
      "Evaluate proposed dissolution and storage conditions using evidence for the actual material form.",
      "Link a qualifying ingredient lot to a separately modelled medicinal product.",
      "Flag missing hazard, stability or identity evidence before release or use."
    ],
    "agent_conduct": {
      "may": [
        "Describe methylnaltrexone's action on gut opioid receptors and its use in opioid-induced constipation.",
        "Explain that it does not block pain relief in the brain under normal use."
      ],
      "must_not": [
        "Recommend, dose or supply it to a person without a prescriber's decision.",
        "Advise its use when bowel obstruction is suspected.",
        "Present it as a treatment for opioid overdose or addiction."
      ],
      "requires_human": [
        "Any decision to start or stop it, especially in palliative care."
      ]
    },
    "ethics": {
      "considerations": [
        "Many users are in palliative care, where comfort and dignity must guide every decision."
      ],
      "affected_parties": [
        "Patients on opioids",
        "Palliative care patients",
        "Carers"
      ]
    },
    "owners": {
      "steward": "The marketing authorisation holder; the prescriber answers for each use.",
      "master_systems": [
        "National medicines registers"
      ]
    },
    "visual_identification": [
      "Supplied as an injection or tablets; identity is confirmed by label and pharmacy records."
    ],
    "failure_modes_and_hazards": [
      "Bowel perforation in patients with gut lesions or obstruction.",
      "Abdominal pain and diarrhoea."
    ],
    "what_it_is_for": [
      "Methylnaltrexone bromide is encountered in pharmaceutical manufacture, analytical testing and research on peripheral opioid receptor antagonism.",
      "It is used as an active pharmaceutical ingredient in medicines for opioid-induced constipation, with suitability depending on documented identity, purity and the intended product."
    ],
    "standards_and_regulation": [
      "The Anatomical Therapeutic Chemical classification maintained by the World Health Organization Collaborating Centre for Drug Statistics Methodology places methylnaltrexone bromide under A06AH01, within peripheral opioid receptor antagonists."
    ]
  },
  "sources": [
    {
      "id": "wikidata",
      "title": "Wikidata item Q59904170: methylnaltrexone bromide",
      "url": "https://www.wikidata.org/wiki/Q59904170",
      "url_status": "live",
      "what_it_supports": "identity and sense of the item",
      "checked_by": "wikidata-api"
    },
    {
      "id": "wikipedia-en",
      "title": "Wikipedia: Methylnaltrexone",
      "url": "https://en.wikipedia.org/wiki/Methylnaltrexone",
      "url_status": "live",
      "what_it_supports": "general description of the item",
      "checked_by": "wikidata-api sitelink"
    }
  ],
  "structure": {
    "bundles": [
      {
        "id": "salt-and-stereochemical-identity",
        "name": "Salt and stereochemical identity",
        "description": "Establish exactly which methylnaltrexone species the entry and a physical sample represent.",
        "rationale": "Cation identity, bromide composition and stereochemistry jointly determine this substance's boundary.",
        "layers": [
          {
            "id": "cation-structure",
            "name": "Cation structure",
            "description": "Resolve molecular connectivity and stereochemical identity.",
            "findings": [
              {
                "id": "reference-structure-match",
                "name": "Reference structure match",
                "description": "Require structural evidence that can distinguish the intended substance from naltrexone and stereochemical alternatives.",
                "questions": [
                  {
                    "text": "Which authenticated structure and stereochemical identifier define the registered methylnaltrexone bromide?",
                    "kind": "definition",
                    "id": "reference-structure-match-q01"
                  },
                  {
                    "text": "Which analytical comparison distinguishes the intended stereochemistry from possible stereoisomer impurities?",
                    "kind": "measurement",
                    "id": "reference-structure-match-q02"
                  }
                ]
              }
            ]
          },
          {
            "id": "bromide-and-identifiers",
            "name": "Bromide and identifiers",
            "description": "Resolve counterion composition and external identity mappings.",
            "findings": [
              {
                "id": "salt-record-resolution",
                "name": "Salt record resolution",
                "description": "Map identifiers to the complete salt and document any differences in stereochemical or hydration specificity.",
                "questions": [
                  {
                    "text": "What measurements confirm bromide identity and its molar ratio to the methylnaltrexone cation?",
                    "kind": "measurement",
                    "id": "salt-record-resolution-q01"
                  },
                  {
                    "text": "Which CAS, PubChem, EC or other authority records refer to this exact salt rather than the cation or a stereoisomer?",
                    "kind": "provenance",
                    "id": "salt-record-resolution-q02"
                  }
                ]
              }
            ]
          }
        ]
      },
      {
        "id": "assay-and-lot-quality",
        "name": "Assay and lot quality",
        "description": "Determine how much qualifying methylnaltrexone bromide a lot contains.",
        "rationale": "A nominal mass or purity percentage is ambiguous without its chemical basis and impurity evidence.",
        "layers": [
          {
            "id": "content-basis",
            "name": "Content basis",
            "description": "Reconcile salt content, cation equivalents and moisture corrections.",
            "findings": [
              {
                "id": "comparable-content",
                "name": "Comparable content",
                "description": "Keep salt mass and cation-equivalent mass explicit; the product label distinguishes these quantities. [RELISTOR prescribing information](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=c488fb7c-0a5b-487c-b452-996809d1cb99).",
                "questions": [
                  {
                    "text": "Does the reported assay quantify methylnaltrexone bromide or methylnaltrexone cation equivalents?",
                    "kind": "definition",
                    "id": "comparable-content-q01"
                  },
                  {
                    "text": "Which water, solvent and reference-standard potency corrections were applied to the result?",
                    "kind": "measurement",
                    "id": "comparable-content-q02"
                  }
                ]
              }
            ]
          },
          {
            "id": "impurities-and-release",
            "name": "Impurities and release",
            "description": "Connect analytical quality to a specified intended use.",
            "findings": [
              {
                "id": "lot-fitness-evidence",
                "name": "Lot fitness evidence",
                "description": "Assess stereoisomers, related substances and residual materials against a traceable lot specification.",
                "questions": [
                  {
                    "text": "Which tests quantify stereoisomer impurities, related substances, water and residual solvents, and with what reporting limits?",
                    "kind": "measurement",
                    "id": "lot-fitness-evidence-q01"
                  },
                  {
                    "text": "Which approved specification and certificate of analysis support releasing this lot for its declared use?",
                    "kind": "action",
                    "id": "lot-fitness-evidence-q02"
                  }
                ]
              }
            ]
          }
        ]
      },
      {
        "id": "physical-form-and-stability",
        "name": "Physical form and stability",
        "description": "Record the actual material form and the conditions under which it remains suitable.",
        "rationale": "Bulk salt and formulated solutions cannot share physical-property or shelf-life assumptions without evidence.",
        "layers": [
          {
            "id": "solid-and-solution-properties",
            "name": "Solid and solution properties",
            "description": "Establish form-specific properties relevant to weighing, dissolution and processing.",
            "findings": [
              {
                "id": "conditioned-property-measurements",
                "name": "Conditioned property measurements",
                "description": "Tie solid-form identification, solubility and thermal measurements to sample composition and experimental conditions.",
                "questions": [
                  {
                    "text": "Is the tested salt crystalline, amorphous, hydrated or solvated, and what measurements establish that state?",
                    "kind": "measurement",
                    "id": "conditioned-property-measurements-q01"
                  },
                  {
                    "text": "What solubility and thermal-event data apply at specified solvent, pH, temperature and pressure conditions?",
                    "kind": "measurement",
                    "id": "conditioned-property-measurements-q02"
                  },
                  {
                    "text": "Does a reported thermal endpoint represent melting, solvent loss or decomposition, and is a boiling point meaningful?",
                    "kind": "boundary",
                    "id": "conditioned-property-measurements-q03"
                  }
                ]
              }
            ]
          },
          {
            "id": "storage-and-degradation",
            "name": "Storage and degradation",
            "description": "Connect exposure history and stability data to remaining material fitness.",
            "findings": [
              {
                "id": "supported-retest-status",
                "name": "Supported retest status",
                "description": "Use stability-indicating evidence for the bulk salt or specified solution rather than borrowing finished-product expiry conditions.",
                "questions": [
                  {
                    "text": "Which stability studies support this material's container, temperature, humidity and light limits?",
                    "kind": "provenance",
                    "id": "supported-retest-status-q01"
                  },
                  {
                    "text": "After an excursion or prolonged storage, which results determine whether to retest, release or reject the lot?",
                    "kind": "action",
                    "id": "supported-retest-status-q02"
                  }
                ]
              }
            ]
          }
        ]
      },
      {
        "id": "pharmacology-and-product-boundary",
        "name": "Pharmacology and product boundary",
        "description": "Connect substance identity to biological action and separately governed medicinal presentations.",
        "rationale": "The active moiety's pharmacology explains relevance but does not establish product interchangeability or patient suitability.",
        "layers": [
          {
            "id": "peripheral-antagonism",
            "name": "Peripheral antagonism",
            "description": "Represent receptor activity with its experimental and physiological limits.",
            "findings": [
              {
                "id": "activity-and-distribution",
                "name": "Activity and distribution",
                "description": "Methylnaltrexone is a mu-opioid receptor antagonist whose quaternary structure restricts blood-brain barrier passage; restricted passage should not be modelled as absolute exclusion. [RELISTOR prescribing information](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=c488fb7c-0a5b-487c-b452-996809d1cb99).",
                "questions": [
                  {
                    "text": "Which receptor assays establish antagonist activity, and do their concentrations use salt or cation units?",
                    "kind": "measurement",
                    "id": "activity-and-distribution-q01"
                  },
                  {
                    "text": "Which evidence defines the limits of peripheral selectivity under altered barrier integrity or exposure?",
                    "kind": "boundary",
                    "id": "activity-and-distribution-q02"
                  }
                ]
              }
            ]
          },
          {
            "id": "ingredient-to-medicine",
            "name": "Ingredient to medicine",
            "description": "Separate an ingredient lot from authorised formulations and therapeutic decisions.",
            "findings": [
              {
                "id": "product-linkage",
                "name": "Product linkage",
                "description": "Link methylnaltrexone bromide to a product through ingredient identity, specification and quantity basis.",
                "questions": [
                  {
                    "text": "Which product record identifies this salt as its active ingredient and specifies the relevant ingredient quality?",
                    "kind": "provenance",
                    "id": "product-linkage-q01"
                  },
                  {
                    "text": "Which route, formulation, indication and dosing decisions must be delegated to the medicinal-product and patient-care models?",
                    "kind": "boundary",
                    "id": "product-linkage-q02"
                  }
                ]
              }
            ]
          }
        ]
      },
      {
        "id": "handling-and-permitted-use",
        "name": "Handling and permitted use",
        "description": "Establish evidence for handling and using methylnaltrexone bromide in a particular setting.",
        "rationale": "Medicinal activity does not supply an occupational hazard classification or authorise every grade for clinical manufacture.",
        "layers": [
          {
            "id": "occupational-and-environmental-hazards",
            "name": "Occupational and environmental hazards",
            "description": "Resolve hazards for the supplied salt and its actual exposure form.",
            "findings": [
              {
                "id": "applicable-hazard-evidence",
                "name": "Applicable hazard evidence",
                "description": "Keep workplace classification, exposure controls and disposal evidence separate from clinical adverse-effect information.",
                "questions": [
                  {
                    "text": "Which current SDS and jurisdiction-specific classification apply to this methylnaltrexone bromide material?",
                    "kind": "provenance",
                    "id": "applicable-hazard-evidence-q01"
                  },
                  {
                    "text": "What exposure-limit or occupational-band evidence supports controls for weighing powder or handling solutions?",
                    "kind": "action",
                    "id": "applicable-hazard-evidence-q02"
                  },
                  {
                    "text": "Which substance-specific evidence determines spill response and waste disposal requirements?",
                    "kind": "action",
                    "id": "applicable-hazard-evidence-q03"
                  }
                ]
              }
            ]
          },
          {
            "id": "grade-and-jurisdiction",
            "name": "Grade and jurisdiction",
            "description": "Determine permitted uses from material qualification and applicable authority records.",
            "findings": [
              {
                "id": "use-qualification",
                "name": "Use qualification",
                "description": "Require a documented match between supplier qualification, material grade, intended operation and jurisdiction.",
                "questions": [
                  {
                    "text": "Which manufacturer, lot and quality-system records substantiate the declared methylnaltrexone bromide grade?",
                    "kind": "provenance",
                    "id": "use-qualification-q01"
                  },
                  {
                    "text": "Which jurisdiction-specific requirements must be satisfied before this lot can enter pharmaceutical manufacture or another proposed use?",
                    "kind": "action",
                    "id": "use-qualification-q02"
                  }
                ]
              }
            ]
          }
        ]
      },
      {
        "id": "evidence-and-external-alignment",
        "name": "Evidence and external alignment",
        "description": "What the world already says about this thing, gathered so the model can be checked against it.",
        "rationale": "A model that cannot be lined up against existing standards, identifiers and practice cannot be adopted by anyone who already uses them.",
        "layers": [
          {
            "id": "reported-evidence",
            "name": "Reported evidence",
            "description": "Findings from the breadth pass, kept separate from the structural claims.",
            "findings": [
              {
                "id": "evidence-confidence-notes",
                "name": "Check these first",
                "description": "Recalled without web access and unsourced; every item is a lead to verify.",
                "evidence": [
                  "This description is recalled knowledge; no sources were consulted.",
                  "Verify CAS, PubChem, and other registry identifiers against the exact salt and stereochemical identity.",
                  "Purity specifications, solid-state forms, thermal properties, and substance-level hazard classification require verification; clinical adverse effects do not establish a GHS classification."
                ],
                "questions": [
                  {
                    "id": "evidence-confidence-notes-q01",
                    "text": "Which of these check these first hold for the sense of methylnaltrexone bromide this model covers, and on what evidence?",
                    "kind": "provenance"
                  }
                ]
              },
              {
                "id": "evidence-identifiers",
                "name": "Identifiers and schemes",
                "description": "Recalled without web access and unsourced; every item is a lead to verify.",
                "evidence": [
                  {
                    "scheme": "International Nonproprietary Name (INN)",
                    "value_or_pattern": "methylnaltrexone",
                    "note": "Names the active moiety; methylnaltrexone bromide specifies its bromide salt."
                  },
                  {
                    "scheme": "Molecular formula",
                    "value_or_pattern": "C21H26BrNO4",
                    "note": "Formula of the anhydrous bromide salt."
                  }
                ],
                "questions": [
                  {
                    "id": "evidence-identifiers-q01",
                    "text": "Which of these identifiers and schemes hold for the sense of methylnaltrexone bromide this model covers, and on what evidence?",
                    "kind": "provenance"
                  }
                ]
              },
              {
                "id": "evidence-standards-and-regulation",
                "name": "Standards and regulation",
                "description": "Recalled without web access and unsourced; every item is a lead to verify.",
                "evidence": [
                  "United States Food and Drug Administration prescribing information governs approved indications, contraindications, and warnings for methylnaltrexone bromide drug products."
                ],
                "questions": [
                  {
                    "id": "evidence-standards-and-regulation-q01",
                    "text": "Which of these standards and regulation hold for the sense of methylnaltrexone bromide this model covers, and on what evidence?",
                    "kind": "provenance"
                  }
                ]
              },
              {
                "id": "evidence-real-world-use",
                "name": "Real-world use",
                "description": "Recalled without web access and unsourced; every item is a lead to verify.",
                "evidence": [
                  "Active pharmaceutical ingredient in medicines for opioid-induced constipation.",
                  "Formulated into oral tablets and subcutaneous injections."
                ],
                "questions": [
                  {
                    "id": "evidence-real-world-use-q01",
                    "text": "Which of these real-world use hold for the sense of methylnaltrexone bromide this model covers, and on what evidence?",
                    "kind": "provenance"
                  }
                ]
              },
              {
                "id": "evidence-measurements",
                "name": "Typical measurements",
                "description": "Recalled without web access and unsourced; every item is a lead to verify.",
                "evidence": [
                  {
                    "quantity": "Molar mass of the anhydrous bromide salt",
                    "typical_range": "436.34",
                    "unit": "g/mol"
                  }
                ],
                "questions": [
                  {
                    "id": "evidence-measurements-q01",
                    "text": "Which of these typical measurements hold for the sense of methylnaltrexone bromide this model covers, and on what evidence?",
                    "kind": "provenance"
                  }
                ]
              },
              {
                "id": "evidence-failure-modes-and-hazards",
                "name": "Failure modes and hazards",
                "description": "Recalled without web access and unsourced; every item is a lead to verify.",
                "evidence": [
                  "Gastrointestinal perforation has been reported, particularly in patients with conditions that compromise gastrointestinal wall integrity.",
                  "Drug products are contraindicated in known or suspected gastrointestinal obstruction and in patients at increased risk of recurrent obstruction.",
                  "Can cause abdominal pain, diarrhea, and nausea; severe or persistent diarrhea is a clinically significant adverse effect.",
                  "Opioid withdrawal symptoms can occur; disruption of the blood-brain barrier may increase the risk of withdrawal or reduced analgesia."
                ],
                "questions": [
                  {
                    "id": "evidence-failure-modes-and-hazards-q01",
                    "text": "Which of these failure modes and hazards hold for the sense of methylnaltrexone bromide this model covers, and on what evidence?",
                    "kind": "provenance"
                  }
                ]
              },
              {
                "id": "evidence-regional-variation",
                "name": "Regional variation",
                "description": "Recalled without web access and unsourced; every item is a lead to verify.",
                "evidence": [
                  "Approved indications, available dosage forms, and prescribing requirements depend on jurisdiction."
                ],
                "questions": [
                  {
                    "id": "evidence-regional-variation-q01",
                    "text": "Which of these regional variation hold for the sense of methylnaltrexone bromide this model covers, and on what evidence?",
                    "kind": "provenance"
                  }
                ]
              },
              {
                "id": "evidence-neighbours",
                "name": "Neighbouring kinds and how to tell them apart",
                "description": "Recalled without web access and unsourced; every item is a lead to verify.",
                "evidence": [
                  {
                    "name": "methylnaltrexone",
                    "difference": "Names the pharmacologically active cation; methylnaltrexone bromide explicitly includes the bromide counterion."
                  },
                  {
                    "name": "naltrexone",
                    "difference": "Methylnaltrexone has an additional nitrogen-bound methyl group and a permanent positive charge, limiting central nervous system penetration compared with naltrexone."
                  },
                  {
                    "name": "naloxegol",
                    "difference": "A distinct, PEG-modified opioid antagonist with a different molecular structure; it is not a salt or grade of methylnaltrexone."
                  },
                  {
                    "name": "Relistor",
                    "difference": "A medicinal-product brand containing methylnaltrexone bromide; the product includes a dosage form and excipients beyond the substance."
                  }
                ],
                "questions": [
                  {
                    "id": "evidence-neighbours-q01",
                    "text": "Which of these neighbouring kinds and how to tell them apart hold for the sense of methylnaltrexone bromide this model covers, and on what evidence?",
                    "kind": "provenance"
                  }
                ]
              }
            ]
          }
        ]
      }
    ]
  },
  "openQuestions": [
    "Which authoritative CAS and EC mappings unambiguously resolve the intended stereochemistry and distinguish the bromide salt from less-specific records?",
    "Which solid forms, hydration states, solubility measurements and thermal endpoints are supported by primary measurements for the relevant grade?",
    "Which current compendial or approved specifications define assay, stereoisomer, related-substance and residual-solvent limits?",
    "What bulk-material stability evidence establishes packaging, storage conditions and retest periods independently of finished medicines?",
    "Which current SDS classifications, occupational exposure limits or bands, and environmental disposal requirements apply in the intended jurisdiction?"
  ],
  "statistics": {
    "bundles": 6,
    "layers": 11,
    "findings": 18,
    "questions": 30
  }
}
