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Biomedical subjects

I Nakanishi

Publications and source records attributed to I Nakanishi.

At least 19 recordsLinked to original sources

Interaction between the left-handed Z-DNA and polyamine-2. The crystal structure of the d(CG)3 and spermidine complex.

This paper deals with the crystal structure of d(CG)3-spermidine complex. The DNA fragment, d(CG)3, was crystallized with N-(2-amino-propyl)-1,4-diamino-butane, PA(34), spermidine. The results of its X-ray crystallographic analysis showed many intermolecular contacts between d(CG)3 and spermidine, but the binding mode of spermidine to the d(CG)3 molecule is different from that of the d(CG)3 and N-(2-amino-ethyl)-1,4-diamino-butane [PA(24)] complex: a spermidine molecule bound to the d(CG)3 and its symmetrically related neighboring d(CG)3 molecules through the water molecules with hydrogen bonds, while one PA(24) molecule connected directly to one d(CG)3 molecule, but not to its neighboring d(CG)3 molecule. In the crystal, the d(CG)3 molecule was the left-handed Z-form, and three magnesium cations and a sodium cation were observed around the d(CG)3 moiety with different binding modes from the case of the d(CG)3-PA(24) complex.

Base Sequence

Studies on cerebral protective agents. IX. Synthesis of novel 1,2,3,4-tetrahydroisoquinolines as N-methyl-D-aspartate antagonists.

A series of 1,2,3,4-tetrahydroisoquinoline derivatives were synthesized and evaluated for anticonvulsant activity against intracerebro-ventriculas (i.c.v.) N-methyl-D-aspartate (NMDA)-induced seizures in mice. Among these compounds, (+)-1-methyl-1-phenyl-1,2,3,4-tetrahydroisoquinoline hydrochloride ((+)-1a, FR115427) was the most effective anticonvulsant, and also protected CA1 hippocampal neurons from ischemia-induced neuronal degeneration in rats at 32 mg/kg i.p. In addition, (+)-1a showed anti-hypoxic activity in mice at 3.2-32 mg/kg i.p. The absolute configuration at the C-1 position of the isoquinoline ring was determined to be S by a single-crystal X-ray analysis of (+)-1a (+)-di-p-toluoyl-D-tartrate. Structure-activity relationships with regard to the anticonvulsant activity of this series of compounds are discussed, and the three-dimensional structures of (S)-(+)-1a and MK801 are compared.

Animals

Matrix metalloproteinase 9 (gelatinase B) is expressed in multinucleated giant cells of human giant cell tumor of bone and is associated with vascular invasion.

Human giant cell tumor (GCT) consists of multinucleated giant cells and mononuclear stromal cells, and is characterized by frequent vascular invasion without distant metastases. To study the role of matrix metalloproteinases (MMPs) in the vascular invasion, we examined production of MMP-1 (tissue collagenase), -2 (gelatinase A), -3 (stromelysin-1), -9 (gelatinase B), and tissue inhibitors of metalloproteinases (TIMP-1 and -2) in GCT. MMP-9 was highly and predominantly expressed in giant cells by both immunohistochemistry and in situ hybridization. Expression of other MMPs was also observed in some cases but was inconstant. Sandwich enzyme immunoassays demonstrated that MMP-9 is the predominant MMP secreted by GCT. There was a definite imbalance between the amounts of MMP-9 and those of TIMPs in the culture media of GCT, leading to detectable gelatinolytic activity in an assay using 14C-gelatin. Gelatin zymography demonstrated the main activity at about 90 kd, which was identified as the zymogen of MMP-9 by immunoblotting. Immunohistochemistry for type IV collagen and laminin, major basement membrane components, showed that disappearance of the proteins is closely associated with MMP-9-positive giant cells. These results indicate the production of MMP-9 by multinucleated giant cells and suggest that the metalloproteinase may contribute to proteolysis associated with vascular invasion and local bone resorption in human GCT.

Adolescent

Matrix metalloproteinase 7 (matrilysin) from human rectal carcinoma cells. Activation of the precursor, interaction with other matrix metalloproteinases and enzymic properties.

Matrix metalloproteinase 7 (MMP-7) has been purified as an inactive zymogen of M(r) 28,000 (proMMP-7) from the culture medium of CaR-1 human rectal carcinoma cells. The NH2-terminal sequence of proMMP-7 is Lys-Pro-Lys-Pro-Gln-Glu, which is identical to that of matrilysin. The zymogen is activated by 4-aminophenylmercuric acetate (APMA), yielding an intermediate form of M(r) 21,000 and an active species of M(r) 19,000 which shows the new NH2-terminal sequence of Tyr78-Ser-Leu-Phe-Pro-Asn-Ser. Although trypsin fully activates the zymogen, the activation rate by plasmin or leukocyte elastase is confined to approximately 50%. ProMMP-7 can be activated by MMP-3 (stromelysin 1) to its full activity in a single-step mechanism and generates the same NH2 terminus obtained by APMA activation, whereas MMP-1 (tissue collagenase), MMP-2 (gelatinase A), and MMP-9 (gelatinase B) do not have such an effect. On the other hand, proMMP-1 is activated by MMP-7 to an activity similar to that obtained by APMA and the activation by MMP-7 is enhanced up to approximately 6.5 fold in the presence of APMA. This enhanced activity is donated by specific cleavage at the Gln80-Phe81 bond of proMMP-1. MMP-7 can also activate proMMP-9 up to approximately 50% of the full activity with a new NH2 terminus of Leu16-Arg-Thr-(Asn)-Leu. Incubation of proMMP-2 or proMMP-3 with MMP-7 results in no activation of these proMMPs. MMP-7 degrades type IV collagen, laminin-1, fibronectin, proteoglycan, type I gelatin, and insoluble elastin. These results suggest that in vivo MMP-7 may play a role in degradation of extracellular matrix macromolecules in concert with MMP-1, -3, and -9 under pathological conditions.

Collagenases

Conformational studies on the four stereoisomers of the novel anticholinergic 4-(dimethylamino)-2-phenyl-2-(2-pyridyl)pentanamide.

To interpret differences in the anticholinergic activity among the four stereoisomers of 4-(dimethylamino)-2-phenyl-2-(2-pyridyl)pentanamide (1-4), we performed conformational studies using the semiempirical molecular orbital method. The structures of the global minimum-energy conformations obtained for 1-4, however, could not explain the different activities, particularly in terms of distances between the essential pharmacophores. We thus implemented superimposition studies, using the energetically stable conformations of the most active stereoisomer, 1(2S,4R), as a template. The energy penalties for a conformation change of the less active stereoisomers 2-4 from their global minimum-energy structure to a new conformation, fitting onto the global minimum-energy conformation of 1, appear to account for the differences in the pharmacological potency better than using the other conformations of 1 as a template. We thus presume that the global minimum-energy conformation of 1 is closely related to the bioactive conformation for these anticholinergics, and also that the pharmacological potency is linked to how readily these substances can change their conformations to fit the muscarinic receptor.

Animals

Inhibitory effects of adhesion oligopeptides on the invasion of squamous carcinoma cells with special reference to implication of alpha v integrins.

We studied invasion-related adhesion events in vitro using three squamous carcinoma cell lines (HSC-3), poorly differentiated type; OSC-19, well-differentiated type; and KB cells, undifferentiated type). An in vitro invasion assay through matrigel in the transwell chamber revealed that HSC-3 cells were most invasive, OSC-19 cells moderately invasive and KB cells least invasive. Inhibition assay of invasion using synthetic peptides RGD, RGDV, RGDS, RGDT, IKVAV and YIGSR, showed that invasion of the three cell lines was significantly inhibited by RGDV. There were other peptides that inhibited invasion significantly including IKVAV for HSC-3, and RGDS and YIGSR for OSC-19. HSC-3 cells and OSC-19 cells adhered to fibronectin, laminin, vitronectin, and type IV collagen, and KB cells did not adhere to laminin but did to fibronectin, vitronectin and collagen type IV. Pretreatment of cells with RGDV peptide in the attachment assay reduced the ability of these cells to bind to vitronectin and fibronectin more efficiently than pretreatment with RGDS. Anti-alpha v antibodies inhibited adhesion of HSC-3, OSC-19 and KB cells to vitronectin, but anti-beta 1 antibodies did not inhibit adhesion. Immunofluorescent microscopic examinations showed that all cell lines were positive for anti-beta 5 and anti-alpha v antibodies, and only HSC-3 cells were positive for anti-beta 3 antibody. alpha 5 beta 1 was not clearly demonstrated in any of the cell lines. RGDV was the most effective inhibitor of squamous cell carcinoma invasion among the synthetic oligopeptides used in this experiment, and it is suggested that it affects alpha v beta 3- and/or alpha v beta 5-mediated carcinoma cell invasion.

Amino Acid Sequence

Covalently-bound human C4b dimers consisting of C4B isotype show higher hemolytic activity than those of C4A in the C3-bypass complement pathway.

The ability to form a covalent dimer of human C4b was investigated with purified isotypes C4A and C4B, and antibody-sensitized liposomes supplemented with C1. In this system, no C4A or C4B formed a complex with the antibody or C1. Whereas both C4A and C4B isotypes formed dimers to a similar extent, C4B formed an ester-linked dimer and C4A an amide-linked dimer. Both of these dimers served as a subunit for the C3-bypass pathway C5 convertase, since liposomes bearing Ab, C1 and a dimer of C4A or C4B, allowed the formation of C5 convertase by the addition of C2. The degree of complement-mediated liposome lysis however, was observed to be 2-3 times higher in the C4B-bearing particles than in those bearing C4A. These results indicate that the second C4b-binding site on the first C4b is different between C4A and C4B, and that in the C3-bypass pathway, C4B has a higher degree of hemolytic activity than C4A, as in the conventional classical complement pathway.

Biopolymers

Human MCAF gene transfer enhances the metastatic capacity of a mouse cachectic adenocarcinoma cell line in vivo.

PURPOSE: To evaluate the effect of monocyte chemotactic and activating factor (MCAF/MCP-1/JE) on tumor progression and metastasis. METHODS: Cachexia-inducing adenocarcinoma cells (cell line colon 26, clone 20) were transfected with either a control plasmid or MCAF expression vector. Spontaneous lung metastases were determined in mouse. RESULTS: The production of MCAF reached 0.4 ng/ml in vitro when transfectant cells were cultured at a cell density of 5 x 10(4) cells/ml for 3 days. Transfection of MCAF expression vector did not affect the growth rate in vitro. Also, after MCAF-transfection, the size of tumors after intra-footpad inoculation was similar to that of the parental cells. When the primary tumors were resected on the 10th day after inoculation, the incidence of spontaneous lung metastasis was less than 20% in both cells. The number of endothelial cells in the primary tumor rapidly increased from the 10th to the 14th day after inoculation, as revealed by immunohistochemical staining. In accordance with enhanced angiogenesis, the incidence rates of spontaneous metastasis increased when the primary tumors were resected on the 14th day after inoculation. Moreover, the spontaneous lung metastases were augmented in the animals injected with MCAF-transfectants compared to those injected with parental cells with a concomitant increase of angiogenesis. CONCLUSIONS: These results suggest that MCAF may augment the metastastic potential by modulating tumor associated angiogenesis.

Adenocarcinoma

Prevention of endotoxin shock by an antibody against leukocyte integrin beta 2 through inhibiting production and action of TNF.

Septic shock remains a serious disorder associated with high mortality. Accumulating evidence indicates that TNF is a major and essential mediator of endotoxin shock. We report here that administration of an antibody against CD18 dramatically reduced endotoxin-induced shock in rabbits as revealed by prevention of severe hypotension, metabolic acidosis and a pathological change suggestive of disseminated intravascular coagulation with concomitant inhibition of elevation of plasma TNF activity. The anti-CD18 antibody also inhibited the hypotension induced by administering recombinant TNF. Furthermore, an antibody against a ligand for CD18 complexes, intercellular adhesion molecule-1, also prevented TNF-induced shock as well as endotoxin shock in rabbits. These observations suggest that adhesion of leukocytes to endothelium may be of primary importance in the action of TNF as well as in the production of TNF in vivo and that the antibody against adhesion molecules could be of therapeutic benefit in life-threatening septic shock in humans.

Acute-Phase Reaction

Pulmonary vasculitis with hypereosinophilia and episodic pulmonary hypertension: report of three siblings.

Three siblings with eosinophilia who developed pulmonary hypertension are reported. They consisted of a 3 year old boy (case 1), a 9 year old boy (case 2) and a 13 year old girl (case 3), all of whom died within an 18 month period of severe episodic attacks of pulmonary hypertension and the resultant low cardiac output. Marked peripheral eosinophilia was found in cases 1 and 2, and mild eosinophilia in case 3. Open lung biopsy of case 1 revealed pulmonary arteritis with massive eosinophilic infiltration and intimal thickening of muscular arteries of 300-1500 microns in diameter. At autopsy, cases 2 and 3 showed almost similar findings, comprising widespread obliteration of the pulmonary arteries by concentric intimal thickening, medial hypertrophy and recanalized thrombi of arterioles. Rarely, there were foci of granulomas in the thickened intima surrounding birefringent foreign bodies. There were small areas of infarction in the lungs and heart due to arterial thrombi. Vascular lesions other than those in the lungs were mild and almost limited to the branches of the coronary arteries. Therefore, the present cases appear to be a single disease of pulmonary hypertension secondary to endothelial injury and the resultant intimal fibrosis probably evoked by toxic substances, although such agents were not confirmed.

Adolescent

Integrin distribution in gastric carcinoma: association of beta 3 and beta 5 integrins with tumor invasiveness.

Immunolocalization of a variety of integrins using monoclonal antibodies against beta 3, beta 5, alpha 3 beta 1 and alpha 6, and polyclonal antibodies against vitronectin receptor (alpha v beta 3) and beta 1 were investigated on PLP-fixed paraffin sections of 19 cases of advanced gastric carcinomas. The beta 5 integrin, which pairs only with the alpha v subunit, was positive in seven cases (37%), and was associated closely with scirrhous invasion (P < 0.05). beta 5 was positive chiefly in the cytoplasm of carcinoma cells and infrequently in cell membranes. beta 3, which is another subunit pairing with alpha v, was positive in six cases (32%), and tended to be associated with scirrhous invasion (P < 0.01). beta 3 was also located chiefly in the cytoplasm. Five of the seven beta 5-positive cases showed coexpression of beta 3. Polyclonal antibodies to alpha v beta 3 also showed a significant difference among the amounts of stroma (P < 0.05). Anti-beta 1 antibodies showed clear positivity in many cases (89%). Of the beta 1 integrins, alpha 3 beta 1 was positive in a few cases (26%) without any preferential pattern, and laminin receptor subunit alpha 6 stained on cell membranes of neoplastic epithelia in many cases of carcinoma (89%) except for mucinous carcinoma These distinctive patterns of integrin positivity indicate a close association of beta 5 and beta 3 expression with scirrhous invasion in gastric carcinoma.

Adult

Immunohistochemical study on collagenous proteins and biophysical analysis of crystals in extraskeletal chondroma.

The immunohistological distribution of collagen types I, II, III, and VI in five cases of extraskeletal chondroma was examined and compared with that in six cases of enchondroma. In addition, the composition of crystals deposited in three cases of extraskeletal chondroma were biophysically analyzed with special attention to the relationship between the collagen types of the matrix and the crystal deposition. In extraskeletal chondroma, immunoreactivity of type II collagen in the extracellular matrix and type VI collagen in the pericellular area, which were strongly and diffusely recognized in the normal hyaline cartilage and enchondroma, was diminished. Instead, additional types of collagen, types I and III, were demonstrated in the matrix. Electron roentgenographic microanalysis and infrared light spectroscopic analysis revealed that calcium pyrophosphate dihydrate (CPPD) was included in the crystals of extraskeletal chondroma. CPPD crystals were observed in/around collagen types I and III. The possible relationship between the difference of collagen composition in the matrix and the CPPD crystal deposition is discussed.

Adult

Human glomerular epithelial cells synthesize and secrete the third component of complement.

Complement proteins in serum are mainly synthesized by hepatocytes. Recently, many cell types have been reported to synthesize complement in various tissues. In this study, we report the synthesis and secretion of the third component of complement (C3) by cultured glomerular epithelial cells (GEC). Using reverse transcriptase polymerase reaction, we have found that GEC and whole kidney expressed the C3 mRNA for C3. By ELISA, we have found that C3 was secreted in culture supernatants harvested from cultured GEC. The secretion of C3 is regulated by proinflammatory cytokines (IL-1 beta, TNF-alpha and IL-6). IL-1 beta is shown to be the most potent stimulator of C3 secretion from GEC. The exact significance of C3 produced at glomerular site is not clear, but its upregulation by proinflammatory cytokines may suspect a role in local activation of complement which may lead to glomerular injury. We further studied the expression of C3 step regulatory proteins (membrane cofactor protein (MCP), decay-accelerating factor (DAF), CR-1 and CD59 (a terminal step regulatory protein) by cultured GEC. Treatment of GEC by proinflammatory cytokines IL-1 beta, TGF-beta, TNF-alpha and IL-6 did not modify the expression of MCP, DAF and CR-1 whereas an increase in the expression of CD59 could be observed after treatment with IL-1 beta and TGF-beta. These results indicate that the expression of these regulatory proteins is tissue specific and may be implicated in inflammatory processes.

Antigens, CD

Studies on cerebral protective agents. VIII. Synthesis of 2-aminothiazoles and 2-thiazolecarboxamides with anti-anoxic activity.

Various 2-aminothiazoles (2a-s and 3a-g) and 2-thiazolecarboxamides (4a-h), possessing a nitrogenous basic moiety at the C-2 position of the thiazole ring, were prepared and tested for anti-anoxic (AA) activity in mice. Among them, N-[2-(4-morpholinyl)ethyl]-4-(3-trifluoromethylphenyl)-2- thiazolecarboxamide hydrochloride (4e, FR108143) (minimum effective doses of 3.2 mg/kg i.p. and 10 mg/kg p.o., respectively) exhibited more potent AA activity than either FK360 or compound 1, each of which has a nitrogenous basic moiety at the C-5 position. The structure-activity relationships with regard to AA activity of this series of compounds are discussed, and the three-dimensional electrostatic potentials (3D-MEP) around the basic nitrogen atom of FK360 and the thiazole derivative (4e) are compared.

Animals

Agents for the treatment of overactive detrusor. VIII. Synthesis and pharmacological properties of 4,4-diphenyl-2-cycloalkenylamines including FK584 and 3,3- or 4,4-diphenylcycloalkylamines.

This article describes the synthesis of 4,4-diphenyl-2-cycloalkenylamines (3, 5a) including FK584 (S(-)-3a) and 3,3- or 4,4-diphenylcycloalkylamines (2, 4, 5b) and their inhibitory activities against detrusor contraction. The order of inhibitory activity (i.v.) of the N-tert-butylamine derivatives against urinary bladder rhythmic contraction in rats was as follows: S(-)-4,4-diphenyl-2-cyclopentenylamine (FK584, S(-)-3a) > 4,4-diphenylcyclohexylamine (5b) = R(-)-3,3-diphenylcyclopentylamine (R(-)-4) > or = 3,3-diphenylcyclobutylamine (2) > or = terodiline hydrochloride (HCl) (1) = RS(+/-)-4,4-diphenyl-2-cyclohexenylamine (5a) > R(+)-4,4-diphenyl-2-cyclopentenylamine (R(+)-3a) > or = S(+)-3,3-diphenylcyclopentylamine (S(+)-4). Although the inhibitory activity of FK584 and compounds R(-)-4 and 5b against detrusor contraction in vitro induced with KCl in guinea-pigs was less potent than that of terodiline HCl, their inhibitory activities against detrusor contractions in vitro induced by electrical field stimulation and carbachol were more potent than those of terodiline HCl.

Amines

Interleukin-1 and its naturally occurring antagonist in peritoneal dialysis patients.

We have assessed the levels of interleukin-1b (IL-1b) and interleukin-1 receptor antagonist (IL-1RA) in both serum and peritoneal dialysate effluents (PDE) from nineteen continuous ambulatory peritoneal dialysis patients (CAPD) without peritonitis and three CAPD patients with peritonitis. IL-1 beta and IL-1RA were tested using a specific ELISA immuno-assay. Fifteen normal healthy volunteers severed as control. The serum levels of IL-1RA in CAPD patients were significantly increased comparatively to their levels in healthy volunteers (p < 0.001). CAPD patients without peritonitis (stable patients) showed relatively low levels of IL-1RA in peritoneal dialysate effluents (114.4 +/- 85.1 pg/ml). Patients with peritonitis showed very high serum levels of IL-1RA at the onset of acute infection (4710 +/- 50 pg/ml). The levels of IL-1RA in PDE were very high during the onset of bacterial peritonitis (5744 +/- 254 pg/ml). The clinical recovery from peritonitis was characterized by a fall in IL-1RA in both serum and dialysate. Serum levels IL-1 beta showed a different pattern, it was not detectable in stable CAPD patients as well as in normal healthy volunteers. It was detectable only in serum of patients with peritonitis (10 +/- 0.8 pg/ml). Likewise, in most stable patients, IL-1 beta-PDE levels were not detectable, but substantial amounts can be detected in PDE during bacterial infection (80 +/- 15 pg/ml). The increase in serum and PDE levels of IL-1 beta during bacterial infection was very rapid, this cytokine disappeared in serum and PDE, 2 or 3 days before the clinical recovery.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult

Localization of matrix metalloproteinase 9 (92-kilodalton gelatinase/type IV collagenase = gelatinase B) in osteoclasts: implications for bone resorption.

BACKGROUND: Matrix metalloproteinase 9 (MMP-9, 92-kD gelatinase/type IV collagenase = gelatinase B) is a member of the MMP gene family and implicated in tissue destruction in the various pathophysiologic conditions. Our previous study showed that MMP-9 purified from human fibrosarcoma cells can cleave the cross-link-containing NH(2)-terminal telopeptides of the alpha 2 chain of type I collagen and collagen types III, IV, and V as well as gelatins. EXPERIMENTAL DESIGN: To investigate the role of MMP-9 in bone resorption we have examined its localization in the human bone tissues by immunohistochemistry and in situ hybridization. The enzymic properties were also biochemically studied. RESULTS: Immunohistochemistry using monoclonal antibodies against MMP-1 (interstitial collagenase), MMP-2 (72-kD gelatinase/type IV collagenase = gelatinase A), MMP-3 (stromelysin-1), MMP-9, and tissue inhibitor of metalloproteinases-1 demonstrated that MMP-9 is localized exclusively in osteoclasts of the bone tissues from normal subjects and patients with rheumatoid arthritis or metastatic carcinoma whereas some osteoclasts are also labeled by anti-(MMP-1) antibody. Northern blot and in situ hybridizations of rheumatoid bone tissues using a RNA probe for MMP-9 exhibited strong signals for the mRNA within osteoclasts. MMP-9 depolymerized acid-insoluble polymers of type I collagen and digested collagen fibrils in the demineralized bone. The gelatinolytic activity of the proteinase was optimal at pH 7.5, but 50 to 80% of the full activity was retained at pH 5.5 to 6.0. It was also 90% active in the presence of 100 mM Ca2+. Degradation of acid-soluble and -insoluble type I collagens by MMP-9 was enhanced at higher concentrations of Ca2+. The zymogen of MMP-9 was activated up to approximately 85% of full activity by incubation at pH 2.3. CONCLUSIONS: These results demonstrate that MMP-9 is produced by osteoclasts in the human bone tissues and suggest that it can degrade bone collagens in concert with MMP-1 and cysteine proteinases in the subosteoclastic microenvironment. This proteinase may play a role in the normal bone remodeling and pathologic bone resorption in the human diseases.

Adolescent

A novel and useful descriptor for hydrophobicity, partition coefficient micellar-water, and its application to a QSAR study of antiplatelet agents.

Herein we describe the introduction and application of a novel and useful descriptor, logarithm of micelle-water partition coefficients (log Pmw), for hydrophobicity of compounds. A QSAR study using log Pmw on antiplatelet activities ex vivo of 2-substituted phenyl and benzimidazolyl-5-methyl-4-(3-pyridyl)imidazoles showed its usefulness. Antiplatelet activities could be rationalized by means of only log Pmw with an excellent correlation (r = 0.772, s = 0.257, F = 11.07 **, n = 18), while use of other descriptors such as CLOGP values and retention factors (k') failed. Pmw values can easily be obtained using a normal HPLC system using a micelle aqueous solution as the mobile phase. HPLC techniques offer the advantage of tolerating lower sample purity, smaller sample size, and being dynamic range, compared with the flask-shaking method for measurement of logarithm of 1-octanol/water partition coefficients (log P), which is widely used in QSAR study. These indicated that log Pmw could be a useful descriptor for hydrophobicity of compounds.

Humans